diff options
| author | obrien <obrien@FreeBSD.org> | 2002-02-01 18:16:02 +0000 |
|---|---|---|
| committer | obrien <obrien@FreeBSD.org> | 2002-02-01 18:16:02 +0000 |
| commit | c9ab9ae440a8066b2c2b85b157b1fdadcf09916a (patch) | |
| tree | 086d9d6c8fbd4fc8fe4495059332f66bc0f8d12b /contrib/gcc/loop.c | |
| parent | 2ecfd8bd04b63f335c1ec6295740a4bfd97a4fa6 (diff) | |
| download | FreeBSD-src-c9ab9ae440a8066b2c2b85b157b1fdadcf09916a.zip FreeBSD-src-c9ab9ae440a8066b2c2b85b157b1fdadcf09916a.tar.gz | |
Enlist the FreeBSD-CURRENT users as testers of what is to become Gcc 3.1.0.
These bits are taken from the FSF anoncvs repo on 1-Feb-2002 08:20 PST.
Diffstat (limited to 'contrib/gcc/loop.c')
| -rw-r--r-- | contrib/gcc/loop.c | 8558 |
1 files changed, 4683 insertions, 3875 deletions
diff --git a/contrib/gcc/loop.c b/contrib/gcc/loop.c index aca291d..a65595f 100644 --- a/contrib/gcc/loop.c +++ b/contrib/gcc/loop.c @@ -1,28 +1,27 @@ /* Perform various loop optimizations, including strength reduction. - Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, - 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, + 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. -This file is part of GNU CC. +This file is part of GCC. -GNU CC is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 2, or (at your option) any later +version. -GNU CC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. You should have received a copy of the GNU General Public License -along with GNU CC; see the file COPYING. If not, write to -the Free Software Foundation, 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. */ - +along with GCC; see the file COPYING. If not, write to the Free +Software Foundation, 59 Temple Place - Suite 330, Boston, MA +02111-1307, USA. */ /* This is the loop optimization pass of the compiler. It finds invariant computations within loops and moves them - to the beginning of the loop. Then it identifies basic and + to the beginning of the loop. Then it identifies basic and general induction variables. Strength reduction is applied to the general induction variables, and induction variable elimination is applied to the basic induction variables. @@ -38,200 +37,151 @@ Boston, MA 02111-1307, USA. */ #include "config.h" #include "system.h" #include "rtl.h" +#include "tm_p.h" #include "obstack.h" +#include "function.h" #include "expr.h" +#include "hard-reg-set.h" +#include "basic-block.h" #include "insn-config.h" -#include "insn-flags.h" #include "regs.h" -#include "hard-reg-set.h" #include "recog.h" #include "flags.h" #include "real.h" #include "loop.h" +#include "cselib.h" #include "except.h" #include "toplev.h" +#include "predict.h" +#include "insn-flags.h" +#include "optabs.h" -/* Vector mapping INSN_UIDs to luids. - The luids are like uids but increase monotonically always. - We use them to see whether a jump comes from outside a given loop. */ - -int *uid_luid; - -/* Indexed by INSN_UID, contains the ordinal giving the (innermost) loop - number the insn is contained in. */ - -int *uid_loop_num; - -/* 1 + largest uid of any insn. */ - -int max_uid_for_loop; - -/* 1 + luid of last insn. */ - -static int max_luid; - -/* Number of loops detected in current function. Used as index to the - next few tables. */ - -static int max_loop_num; - -/* Indexed by loop number, contains the first and last insn of each loop. */ - -static rtx *loop_number_loop_starts, *loop_number_loop_ends; - -/* Likewise for the continue insn */ -static rtx *loop_number_loop_cont; - -/* The first code_label that is reached in every loop iteration. - 0 when not computed yet, initially const0_rtx if a jump couldn't be - followed. - Also set to 0 when there is no such label before the NOTE_INSN_LOOP_CONT - of this loop, or in verify_dominator, if a jump couldn't be followed. */ -static rtx *loop_number_cont_dominator; - -/* For each loop, gives the containing loop number, -1 if none. */ - -int *loop_outer_loop; - -#ifdef HAVE_decrement_and_branch_on_count -/* Records whether resource in use by inner loop. */ - -int *loop_used_count_register; -#endif /* HAVE_decrement_and_branch_on_count */ - -/* Indexed by loop number, contains a nonzero value if the "loop" isn't - really a loop (an insn outside the loop branches into it). */ - -static char *loop_invalid; - -/* Indexed by loop number, links together all LABEL_REFs which refer to - code labels outside the loop. Used by routines that need to know all - loop exits, such as final_biv_value and final_giv_value. - - This does not include loop exits due to return instructions. This is - because all bivs and givs are pseudos, and hence must be dead after a - return, so the presense of a return does not affect any of the - optimizations that use this info. It is simpler to just not include return - instructions on this list. */ - -rtx *loop_number_exit_labels; - -/* Indexed by loop number, counts the number of LABEL_REFs on - loop_number_exit_labels for this loop and all loops nested inside it. */ - -int *loop_number_exit_count; - -/* Nonzero if there is a subroutine call in the current loop. */ - -static int loop_has_call; - -/* Nonzero if there is a volatile memory reference in the current - loop. */ - -static int loop_has_volatile; - -/* Nonzero if there is a tablejump in the current loop. */ - -static int loop_has_tablejump; - -/* Added loop_continue which is the NOTE_INSN_LOOP_CONT of the - current loop. A continue statement will generate a branch to - NEXT_INSN (loop_continue). */ - -static rtx loop_continue; - -/* Indexed by register number, contains the number of times the reg - is set during the loop being scanned. - During code motion, a negative value indicates a reg that has been - made a candidate; in particular -2 means that it is an candidate that - we know is equal to a constant and -1 means that it is an candidate - not known equal to a constant. - After code motion, regs moved have 0 (which is accurate now) - while the failed candidates have the original number of times set. - - Therefore, at all times, == 0 indicates an invariant register; - < 0 a conditionally invariant one. */ +/* Not really meaningful values, but at least something. */ +#ifndef SIMULTANEOUS_PREFETCHES +#define SIMULTANEOUS_PREFETCHES 3 +#endif +#ifndef PREFETCH_BLOCK +#define PREFETCH_BLOCK 32 +#endif +#ifndef HAVE_prefetch +#define HAVE_prefetch 0 +#define CODE_FOR_prefetch 0 +#define gen_prefetch(a,b,c) (abort(), NULL_RTX) +#endif -static varray_type set_in_loop; +/* Give up the prefetch optimizations once we exceed a given threshhold. + It is unlikely that we would be able to optimize something in a loop + with so many detected prefetches. */ +#define MAX_PREFETCHES 100 +/* The number of prefetch blocks that are beneficial to fetch at once before + a loop with a known (and low) iteration count. */ +#define PREFETCH_BLOCKS_BEFORE_LOOP_MAX 6 +/* For very tiny loops it is not worthwhile to prefetch even before the loop, + since it is likely that the data are already in the cache. */ +#define PREFETCH_BLOCKS_BEFORE_LOOP_MIN 2 +/* The minimal number of prefetch blocks that a loop must consume to make + the emitting of prefetch instruction in the body of loop worthwhile. */ +#define PREFETCH_BLOCKS_IN_LOOP_MIN 6 + +/* Parameterize some prefetch heuristics so they can be turned on and off + easily for performance testing on new architecures. These can be + defined in target-dependent files. */ + +/* Prefetch is worthwhile only when loads/stores are dense. */ +#ifndef PREFETCH_ONLY_DENSE_MEM +#define PREFETCH_ONLY_DENSE_MEM 1 +#endif -/* Original value of set_in_loop; same except that this value - is not set negative for a reg whose sets have been made candidates - and not set to 0 for a reg that is moved. */ +/* Define what we mean by "dense" loads and stores; This value divided by 256 + is the minimum percentage of memory references that worth prefetching. */ +#ifndef PREFETCH_DENSE_MEM +#define PREFETCH_DENSE_MEM 220 +#endif -static varray_type n_times_set; +/* Do not prefetch for a loop whose iteration count is known to be low. */ +#ifndef PREFETCH_NO_LOW_LOOPCNT +#define PREFETCH_NO_LOW_LOOPCNT 1 +#endif -/* Index by register number, 1 indicates that the register - cannot be moved or strength reduced. */ +/* Define what we mean by a "low" iteration count. */ +#ifndef PREFETCH_LOW_LOOPCNT +#define PREFETCH_LOW_LOOPCNT 32 +#endif -static varray_type may_not_optimize; +/* Do not prefetch for a loop that contains a function call; such a loop is + probably not an internal loop. */ +#ifndef PREFETCH_NO_CALL +#define PREFETCH_NO_CALL 1 +#endif -/* Contains the insn in which a register was used if it was used - exactly once; contains const0_rtx if it was used more than once. */ +/* Do not prefetch accesses with an extreme stride. */ +#ifndef PREFETCH_NO_EXTREME_STRIDE +#define PREFETCH_NO_EXTREME_STRIDE 1 +#endif -static varray_type reg_single_usage; +/* Define what we mean by an "extreme" stride. */ +#ifndef PREFETCH_EXTREME_STRIDE +#define PREFETCH_EXTREME_STRIDE 4096 +#endif -/* Nonzero means reg N has already been moved out of one loop. - This reduces the desire to move it out of another. */ +/* Do not handle reversed order prefetches (negative stride). */ +#ifndef PREFETCH_NO_REVERSE_ORDER +#define PREFETCH_NO_REVERSE_ORDER 1 +#endif -static char *moved_once; +/* Prefetch even if the GIV is not always executed. */ +#ifndef PREFETCH_NOT_ALWAYS +#define PREFETCH_NOT_ALWAYS 0 +#endif -/* List of MEMs that are stored in this loop. */ +/* If the loop requires more prefetches than the target can process in + parallel then don't prefetch anything in that loop. */ +#ifndef PREFETCH_LIMIT_TO_SIMULTANEOUS +#define PREFETCH_LIMIT_TO_SIMULTANEOUS 1 +#endif -static rtx loop_store_mems; +#define LOOP_REG_LIFETIME(LOOP, REGNO) \ +((REGNO_LAST_LUID (REGNO) - REGNO_FIRST_LUID (REGNO))) -/* The insn where the first of these was found. */ -static rtx first_loop_store_insn; +#define LOOP_REG_GLOBAL_P(LOOP, REGNO) \ +((REGNO_LAST_LUID (REGNO) > INSN_LUID ((LOOP)->end) \ + || REGNO_FIRST_LUID (REGNO) < INSN_LUID ((LOOP)->start))) -typedef struct loop_mem_info { - rtx mem; /* The MEM itself. */ - rtx reg; /* Corresponding pseudo, if any. */ - int optimize; /* Nonzero if we can optimize access to this MEM. */ -} loop_mem_info; +#define LOOP_REGNO_NREGS(REGNO, SET_DEST) \ +((REGNO) < FIRST_PSEUDO_REGISTER \ + ? HARD_REGNO_NREGS ((REGNO), GET_MODE (SET_DEST)) : 1) -/* Array of MEMs that are used (read or written) in this loop, but - cannot be aliased by anything in this loop, except perhaps - themselves. In other words, if loop_mems[i] is altered during the - loop, it is altered by an expression that is rtx_equal_p to it. */ -static loop_mem_info *loop_mems; +/* Vector mapping INSN_UIDs to luids. + The luids are like uids but increase monotonically always. + We use them to see whether a jump comes from outside a given loop. */ -/* The index of the next available slot in LOOP_MEMS. */ +int *uid_luid; -static int loop_mems_idx; +/* Indexed by INSN_UID, contains the ordinal giving the (innermost) loop + number the insn is contained in. */ -/* The number of elements allocated in LOOP_MEMs. */ +struct loop **uid_loop; -static int loop_mems_allocated; +/* 1 + largest uid of any insn. */ -/* Nonzero if we don't know what MEMs were changed in the current loop. - This happens if the loop contains a call (in which case `loop_has_call' - will also be set) or if we store into more than NUM_STORES MEMs. */ +int max_uid_for_loop; -static int unknown_address_altered; +/* 1 + luid of last insn. */ -/* Count of movable (i.e. invariant) instructions discovered in the loop. */ -static int num_movables; +static int max_luid; -/* Count of memory write instructions discovered in the loop. */ -static int num_mem_sets; +/* Number of loops detected in current function. Used as index to the + next few tables. */ -/* Number of loops contained within the current one, including itself. */ -static int loops_enclosed; +static int max_loop_num; /* Bound on pseudo register number before loop optimization. A pseudo has valid regscan info if its number is < max_reg_before_loop. */ -int max_reg_before_loop; - -/* This obstack is used in product_cheap_p to allocate its rtl. It - may call gen_reg_rtx which, in turn, may reallocate regno_reg_rtx. - If we used the same obstack that it did, we would be deallocating - that array. */ - -static struct obstack temp_obstack; +unsigned int max_reg_before_loop; -/* This is where the pointer to the obstack being used for RTL is stored. */ - -extern struct obstack *rtl_obstack; +/* The value to pass to the next call of reg_scan_update. */ +static int loop_max_reg; #define obstack_chunk_alloc xmalloc #define obstack_chunk_free free @@ -247,9 +197,9 @@ struct movable rtx set_dest; /* The destination of this SET. */ rtx dependencies; /* When INSN is libcall, this is an EXPR_LIST of any registers used within the LIBCALL. */ - int consec; /* Number of consecutive following insns + int consec; /* Number of consecutive following insns that must be moved with this one. */ - int regno; /* The register it sets */ + unsigned int regno; /* The register it sets */ short lifetime; /* lifetime of that register; may be adjusted when matching movables that load the same value are found. */ @@ -263,7 +213,7 @@ struct movable that the reg is live outside the range from where it is set to the following label. */ unsigned int done : 1; /* 1 inhibits further processing of this */ - + unsigned int partial : 1; /* 1 means this reg is used for zero-extending. In particular, moving it does not make it invariant. */ @@ -280,117 +230,165 @@ struct movable struct movable *next; }; -static struct movable *the_movables; FILE *loop_dump_stream; -/* For communicating return values from note_set_pseudo_multiple_uses. */ -static int note_set_pseudo_multiple_uses_retval; - /* Forward declarations. */ -static void verify_dominator PROTO((int)); -static void find_and_verify_loops PROTO((rtx)); -static void mark_loop_jump PROTO((rtx, int)); -static void prescan_loop PROTO((rtx, rtx)); -static int reg_in_basic_block_p PROTO((rtx, rtx)); -static int consec_sets_invariant_p PROTO((rtx, int, rtx)); -static int labels_in_range_p PROTO((rtx, int)); -static void count_one_set PROTO((rtx, rtx, varray_type, rtx *)); - -static void count_loop_regs_set PROTO((rtx, rtx, varray_type, varray_type, - int *, int)); -static void note_addr_stored PROTO((rtx, rtx)); -static void note_set_pseudo_multiple_uses PROTO((rtx, rtx)); -static int loop_reg_used_before_p PROTO((rtx, rtx, rtx, rtx, rtx)); -static void scan_loop PROTO((rtx, rtx, rtx, int, int)); +static void find_and_verify_loops PARAMS ((rtx, struct loops *)); +static void mark_loop_jump PARAMS ((rtx, struct loop *)); +static void prescan_loop PARAMS ((struct loop *)); +static int reg_in_basic_block_p PARAMS ((rtx, rtx)); +static int consec_sets_invariant_p PARAMS ((const struct loop *, + rtx, int, rtx)); +static int labels_in_range_p PARAMS ((rtx, int)); +static void count_one_set PARAMS ((struct loop_regs *, rtx, rtx, rtx *)); +static void note_addr_stored PARAMS ((rtx, rtx, void *)); +static void note_set_pseudo_multiple_uses PARAMS ((rtx, rtx, void *)); +static int loop_reg_used_before_p PARAMS ((const struct loop *, rtx, rtx)); +static void scan_loop PARAMS ((struct loop*, int)); #if 0 -static void replace_call_address PROTO((rtx, rtx, rtx)); +static void replace_call_address PARAMS ((rtx, rtx, rtx)); #endif -static rtx skip_consec_insns PROTO((rtx, int)); -static int libcall_benefit PROTO((rtx)); -static void ignore_some_movables PROTO((struct movable *)); -static void force_movables PROTO((struct movable *)); -static void combine_movables PROTO((struct movable *, int)); -static int regs_match_p PROTO((rtx, rtx, struct movable *)); -static int rtx_equal_for_loop_p PROTO((rtx, rtx, struct movable *)); -static void add_label_notes PROTO((rtx, rtx)); -static void move_movables PROTO((struct movable *, int, int, rtx, rtx, int)); -static int count_nonfixed_reads PROTO((rtx)); -static void strength_reduce PROTO((rtx, rtx, rtx, int, rtx, rtx, rtx, int, int)); -static void find_single_use_in_loop PROTO((rtx, rtx, varray_type)); -static int valid_initial_value_p PROTO((rtx, rtx, int, rtx)); -static void find_mem_givs PROTO((rtx, rtx, int, rtx, rtx)); -static void record_biv PROTO((struct induction *, rtx, rtx, rtx, rtx, rtx *, int, int)); -static void check_final_value PROTO((struct induction *, rtx, rtx, - unsigned HOST_WIDE_INT)); -static void record_giv PROTO((struct induction *, rtx, rtx, rtx, rtx, rtx, int, enum g_types, int, rtx *, rtx, rtx)); -static void update_giv_derive PROTO((rtx)); -static int basic_induction_var PROTO((rtx, enum machine_mode, rtx, rtx, rtx *, rtx *, rtx **)); -static rtx simplify_giv_expr PROTO((rtx, int *)); -static int general_induction_var PROTO((rtx, rtx *, rtx *, rtx *, int, int *)); -static int consec_sets_giv PROTO((int, rtx, rtx, rtx, rtx *, rtx *, rtx *)); -static int check_dbra_loop PROTO((rtx, int, rtx, struct loop_info *)); -static rtx express_from_1 PROTO((rtx, rtx, rtx)); -static rtx combine_givs_p PROTO((struct induction *, struct induction *)); -static void combine_givs PROTO((struct iv_class *)); -struct recombine_givs_stats; -static int find_life_end PROTO((rtx, struct recombine_givs_stats *, rtx, rtx)); -static void recombine_givs PROTO((struct iv_class *, rtx, rtx, int)); -static int product_cheap_p PROTO((rtx, rtx)); -static int maybe_eliminate_biv PROTO((struct iv_class *, rtx, rtx, int, int, int)); -static int maybe_eliminate_biv_1 PROTO((rtx, rtx, struct iv_class *, int, rtx)); -static int last_use_this_basic_block PROTO((rtx, rtx)); -static void record_initial PROTO((rtx, rtx)); -static void update_reg_last_use PROTO((rtx, rtx)); -static rtx next_insn_in_loop PROTO((rtx, rtx, rtx, rtx)); -static void load_mems_and_recount_loop_regs_set PROTO((rtx, rtx, rtx, - rtx, int *)); -static void load_mems PROTO((rtx, rtx, rtx, rtx)); -static int insert_loop_mem PROTO((rtx *, void *)); -static int replace_loop_mem PROTO((rtx *, void *)); -static int replace_label PROTO((rtx *, void *)); - -typedef struct rtx_and_int { - rtx r; - int i; -} rtx_and_int; - -typedef struct rtx_pair { +static rtx skip_consec_insns PARAMS ((rtx, int)); +static int libcall_benefit PARAMS ((rtx)); +static void ignore_some_movables PARAMS ((struct loop_movables *)); +static void force_movables PARAMS ((struct loop_movables *)); +static void combine_movables PARAMS ((struct loop_movables *, + struct loop_regs *)); +static int num_unmoved_movables PARAMS ((const struct loop *)); +static int regs_match_p PARAMS ((rtx, rtx, struct loop_movables *)); +static int rtx_equal_for_loop_p PARAMS ((rtx, rtx, struct loop_movables *, + struct loop_regs *)); +static void add_label_notes PARAMS ((rtx, rtx)); +static void move_movables PARAMS ((struct loop *loop, struct loop_movables *, + int, int)); +static void loop_movables_add PARAMS((struct loop_movables *, + struct movable *)); +static void loop_movables_free PARAMS((struct loop_movables *)); +static int count_nonfixed_reads PARAMS ((const struct loop *, rtx)); +static void loop_bivs_find PARAMS((struct loop *)); +static void loop_bivs_init_find PARAMS((struct loop *)); +static void loop_bivs_check PARAMS((struct loop *)); +static void loop_givs_find PARAMS((struct loop *)); +static void loop_givs_check PARAMS((struct loop *)); +static int loop_biv_eliminable_p PARAMS((struct loop *, struct iv_class *, + int, int)); +static int loop_giv_reduce_benefit PARAMS((struct loop *, struct iv_class *, + struct induction *, rtx)); +static void loop_givs_dead_check PARAMS((struct loop *, struct iv_class *)); +static void loop_givs_reduce PARAMS((struct loop *, struct iv_class *)); +static void loop_givs_rescan PARAMS((struct loop *, struct iv_class *, + rtx *)); +static void loop_ivs_free PARAMS((struct loop *)); +static void strength_reduce PARAMS ((struct loop *, int)); +static void find_single_use_in_loop PARAMS ((struct loop_regs *, rtx, rtx)); +static int valid_initial_value_p PARAMS ((rtx, rtx, int, rtx)); +static void find_mem_givs PARAMS ((const struct loop *, rtx, rtx, int, int)); +static void record_biv PARAMS ((struct loop *, struct induction *, + rtx, rtx, rtx, rtx, rtx *, + int, int)); +static void check_final_value PARAMS ((const struct loop *, + struct induction *)); +static void loop_ivs_dump PARAMS((const struct loop *, FILE *, int)); +static void loop_iv_class_dump PARAMS((const struct iv_class *, FILE *, int)); +static void loop_biv_dump PARAMS((const struct induction *, FILE *, int)); +static void loop_giv_dump PARAMS((const struct induction *, FILE *, int)); +static void record_giv PARAMS ((const struct loop *, struct induction *, + rtx, rtx, rtx, rtx, rtx, rtx, int, + enum g_types, int, int, rtx *)); +static void update_giv_derive PARAMS ((const struct loop *, rtx)); +static void check_ext_dependent_givs PARAMS ((struct iv_class *, + struct loop_info *)); +static int basic_induction_var PARAMS ((const struct loop *, rtx, + enum machine_mode, rtx, rtx, + rtx *, rtx *, rtx **)); +static rtx simplify_giv_expr PARAMS ((const struct loop *, rtx, rtx *, int *)); +static int general_induction_var PARAMS ((const struct loop *loop, rtx, rtx *, + rtx *, rtx *, rtx *, int, int *, + enum machine_mode)); +static int consec_sets_giv PARAMS ((const struct loop *, int, rtx, + rtx, rtx, rtx *, rtx *, rtx *, rtx *)); +static int check_dbra_loop PARAMS ((struct loop *, int)); +static rtx express_from_1 PARAMS ((rtx, rtx, rtx)); +static rtx combine_givs_p PARAMS ((struct induction *, struct induction *)); +static int cmp_combine_givs_stats PARAMS ((const PTR, const PTR)); +static void combine_givs PARAMS ((struct loop_regs *, struct iv_class *)); +static int product_cheap_p PARAMS ((rtx, rtx)); +static int maybe_eliminate_biv PARAMS ((const struct loop *, struct iv_class *, + int, int, int)); +static int maybe_eliminate_biv_1 PARAMS ((const struct loop *, rtx, rtx, + struct iv_class *, int, + basic_block, rtx)); +static int last_use_this_basic_block PARAMS ((rtx, rtx)); +static void record_initial PARAMS ((rtx, rtx, void *)); +static void update_reg_last_use PARAMS ((rtx, rtx)); +static rtx next_insn_in_loop PARAMS ((const struct loop *, rtx)); +static void loop_regs_scan PARAMS ((const struct loop *, int)); +static int count_insns_in_loop PARAMS ((const struct loop *)); +static void load_mems PARAMS ((const struct loop *)); +static int insert_loop_mem PARAMS ((rtx *, void *)); +static int replace_loop_mem PARAMS ((rtx *, void *)); +static void replace_loop_mems PARAMS ((rtx, rtx, rtx)); +static int replace_loop_reg PARAMS ((rtx *, void *)); +static void replace_loop_regs PARAMS ((rtx insn, rtx, rtx)); +static void note_reg_stored PARAMS ((rtx, rtx, void *)); +static void try_copy_prop PARAMS ((const struct loop *, rtx, unsigned int)); +static void try_swap_copy_prop PARAMS ((const struct loop *, rtx, + unsigned int)); +static int replace_label PARAMS ((rtx *, void *)); +static rtx check_insn_for_givs PARAMS((struct loop *, rtx, int, int)); +static rtx check_insn_for_bivs PARAMS((struct loop *, rtx, int, int)); +static rtx gen_add_mult PARAMS ((rtx, rtx, rtx, rtx)); +static void loop_regs_update PARAMS ((const struct loop *, rtx)); +static int iv_add_mult_cost PARAMS ((rtx, rtx, rtx, rtx)); + +static rtx loop_insn_emit_after PARAMS((const struct loop *, basic_block, + rtx, rtx)); +static rtx loop_call_insn_emit_before PARAMS((const struct loop *, + basic_block, rtx, rtx)); +static rtx loop_call_insn_hoist PARAMS((const struct loop *, rtx)); +static rtx loop_insn_sink_or_swim PARAMS((const struct loop *, rtx)); + +static void loop_dump_aux PARAMS ((const struct loop *, FILE *, int)); +static void loop_delete_insns PARAMS ((rtx, rtx)); +static HOST_WIDE_INT remove_constant_addition PARAMS ((rtx *)); +void debug_ivs PARAMS ((const struct loop *)); +void debug_iv_class PARAMS ((const struct iv_class *)); +void debug_biv PARAMS ((const struct induction *)); +void debug_giv PARAMS ((const struct induction *)); +void debug_loop PARAMS ((const struct loop *)); +void debug_loops PARAMS ((const struct loops *)); + +typedef struct rtx_pair +{ rtx r1; rtx r2; } rtx_pair; +typedef struct loop_replace_args +{ + rtx match; + rtx replacement; + rtx insn; +} loop_replace_args; + /* Nonzero iff INSN is between START and END, inclusive. */ -#define INSN_IN_RANGE_P(INSN, START, END) \ - (INSN_UID (INSN) < max_uid_for_loop \ +#define INSN_IN_RANGE_P(INSN, START, END) \ + (INSN_UID (INSN) < max_uid_for_loop \ && INSN_LUID (INSN) >= INSN_LUID (START) \ && INSN_LUID (INSN) <= INSN_LUID (END)) -#ifdef HAVE_decrement_and_branch_on_count -/* Test whether BCT applicable and safe. */ -static void insert_bct PROTO((rtx, rtx, struct loop_info *)); - -/* Auxiliary function that inserts the BCT pattern into the loop. */ -static void instrument_loop_bct PROTO((rtx, rtx, rtx)); -#endif /* HAVE_decrement_and_branch_on_count */ - /* Indirect_jump_in_function is computed once per function. */ -int indirect_jump_in_function = 0; -static int indirect_jump_in_function_p PROTO((rtx)); +static int indirect_jump_in_function; +static int indirect_jump_in_function_p PARAMS ((rtx)); -static int compute_luids PROTO((rtx, rtx, int)); +static int compute_luids PARAMS ((rtx, rtx, int)); -static int biv_elimination_giv_has_0_offset PROTO((struct induction *, - struct induction *, rtx)); +static int biv_elimination_giv_has_0_offset PARAMS ((struct induction *, + struct induction *, + rtx)); -/* Relative gain of eliminating various kinds of operations. */ -static int add_cost; -#if 0 -static int shift_cost; -static int mult_cost; -#endif - /* Benefit penalty, if a giv is not replaceable, i.e. must emit an insn to copy the value of the strength reduced giv to its original register. */ static int copy_cost; @@ -398,32 +396,14 @@ static int copy_cost; /* Cost of using a register, to normalize the benefits of a giv. */ static int reg_address_cost; - void init_loop () { - char *free_point = (char *) oballoc (1); rtx reg = gen_rtx_REG (word_mode, LAST_VIRTUAL_REGISTER + 1); - add_cost = rtx_cost (gen_rtx_PLUS (word_mode, reg, reg), SET); - -#ifdef ADDRESS_COST - reg_address_cost = ADDRESS_COST (reg); -#else - reg_address_cost = rtx_cost (reg, MEM); -#endif - - /* We multiply by 2 to reconcile the difference in scale between - these two ways of computing costs. Otherwise the cost of a copy - will be far less than the cost of an add. */ - - copy_cost = 2 * 2; + reg_address_cost = address_cost (reg, SImode); - /* Free the objects we just allocated. */ - obfree (free_point); - - /* Initialize the obstack used for rtl in product_cheap_p. */ - gcc_obstack_init (&temp_obstack); + copy_cost = COSTS_N_INSNS (1); } /* Compute the mapping from uids to luids. @@ -461,23 +441,24 @@ compute_luids (start, end, prev_luid) (or 0 if none should be output). */ void -loop_optimize (f, dumpfile, unroll_p, bct_p) +loop_optimize (f, dumpfile, flags) /* f is the first instruction of a chain of insns for one function */ rtx f; FILE *dumpfile; - int unroll_p, bct_p; + int flags; { - register rtx insn; - register int i; + rtx insn; + int i; + struct loops loops_data; + struct loops *loops = &loops_data; + struct loop_info *loops_info; loop_dump_stream = dumpfile; init_recog_no_volatile (); max_reg_before_loop = max_reg_num (); - - moved_once = (char *) alloca (max_reg_before_loop); - bzero (moved_once, max_reg_before_loop); + loop_max_reg = max_reg_before_loop; regs_may_share = 0; @@ -495,41 +476,33 @@ loop_optimize (f, dumpfile, unroll_p, bct_p) if (max_loop_num == 0) return; + loops->num = max_loop_num; + /* Get size to use for tables indexed by uids. Leave some space for labels allocated by find_and_verify_loops. */ max_uid_for_loop = get_max_uid () + 1 + max_loop_num * 32; - uid_luid = (int *) alloca (max_uid_for_loop * sizeof (int)); - uid_loop_num = (int *) alloca (max_uid_for_loop * sizeof (int)); - - bzero ((char *) uid_luid, max_uid_for_loop * sizeof (int)); - bzero ((char *) uid_loop_num, max_uid_for_loop * sizeof (int)); - - /* Allocate tables for recording each loop. We set each entry, so they need - not be zeroed. */ - loop_number_loop_starts = (rtx *) alloca (max_loop_num * sizeof (rtx)); - loop_number_loop_ends = (rtx *) alloca (max_loop_num * sizeof (rtx)); - loop_number_loop_cont = (rtx *) alloca (max_loop_num * sizeof (rtx)); - loop_number_cont_dominator = (rtx *) alloca (max_loop_num * sizeof (rtx)); - loop_outer_loop = (int *) alloca (max_loop_num * sizeof (int)); - loop_invalid = (char *) alloca (max_loop_num * sizeof (char)); - loop_number_exit_labels = (rtx *) alloca (max_loop_num * sizeof (rtx)); - loop_number_exit_count = (int *) alloca (max_loop_num * sizeof (int)); - -#ifdef HAVE_decrement_and_branch_on_count - /* Allocate for BCT optimization */ - loop_used_count_register = (int *) alloca (max_loop_num * sizeof (int)); - bzero ((char *) loop_used_count_register, max_loop_num * sizeof (int)); -#endif /* HAVE_decrement_and_branch_on_count */ + uid_luid = (int *) xcalloc (max_uid_for_loop, sizeof (int)); + uid_loop = (struct loop **) xcalloc (max_uid_for_loop, + sizeof (struct loop *)); + + /* Allocate storage for array of loops. */ + loops->array = (struct loop *) + xcalloc (loops->num, sizeof (struct loop)); /* Find and process each loop. First, find them, and record them in order of their beginnings. */ - find_and_verify_loops (f); + find_and_verify_loops (f, loops); + + /* Allocate and initialize auxiliary loop information. */ + loops_info = xcalloc (loops->num, sizeof (struct loop_info)); + for (i = 0; i < loops->num; i++) + loops->array[i].aux = loops_info + i; /* Now find all register lifetimes. This must be done after find_and_verify_loops, because it might reorder the insns in the function. */ - reg_scan (f, max_reg_num (), 1); + reg_scan (f, max_reg_before_loop, 1); /* This must occur after reg_scan so that registers created by gcse will have entries in the register tables. @@ -545,8 +518,9 @@ loop_optimize (f, dumpfile, unroll_p, bct_p) /* Now reset it to the actual size we need. See above. */ max_uid_for_loop = get_max_uid (); - /* find_and_verify_loops has already called compute_luids, but it might - have rearranged code afterwards, so we need to recompute the luids now. */ + /* find_and_verify_loops has already called compute_luids, but it + might have rearranged code afterwards, so we need to recompute + the luids now. */ max_luid = compute_luids (f, NULL_RTX, 0); /* Don't leave gaps in uid_luid for insns that have been @@ -564,66 +538,67 @@ loop_optimize (f, dumpfile, unroll_p, bct_p) if (uid_luid[i] == 0) uid_luid[i] = uid_luid[i - 1]; - /* Create a mapping from loops to BLOCK tree nodes. */ - if (unroll_p && write_symbols != NO_DEBUG) - find_loop_tree_blocks (); - /* Determine if the function has indirect jump. On some systems this prevents low overhead loop instructions from being used. */ indirect_jump_in_function = indirect_jump_in_function_p (f); /* Now scan the loops, last ones first, since this means inner ones are done before outer ones. */ - for (i = max_loop_num-1; i >= 0; i--) - if (! loop_invalid[i] && loop_number_loop_ends[i]) - scan_loop (loop_number_loop_starts[i], loop_number_loop_ends[i], - loop_number_loop_cont[i], unroll_p, bct_p); + for (i = max_loop_num - 1; i >= 0; i--) + { + struct loop *loop = &loops->array[i]; - /* If debugging and unrolling loops, we must replicate the tree nodes - corresponding to the blocks inside the loop, so that the original one - to one mapping will remain. */ - if (unroll_p && write_symbols != NO_DEBUG) - unroll_block_trees (); + if (! loop->invalid && loop->end) + scan_loop (loop, flags); + } + + /* If there were lexical blocks inside the loop, they have been + replicated. We will now have more than one NOTE_INSN_BLOCK_BEG + and NOTE_INSN_BLOCK_END for each such block. We must duplicate + the BLOCKs as well. */ + if (write_symbols != NO_DEBUG) + reorder_blocks (); end_alias_analysis (); + + /* Clean up. */ + free (uid_luid); + free (uid_loop); + free (loops_info); + free (loops->array); } /* Returns the next insn, in execution order, after INSN. START and END are the NOTE_INSN_LOOP_BEG and NOTE_INSN_LOOP_END for the loop, - respectively. LOOP_TOP, if non-NULL, is the top of the loop in the + respectively. LOOP->TOP, if non-NULL, is the top of the loop in the insn-stream; it is used with loops that are entered near the bottom. */ static rtx -next_insn_in_loop (insn, start, end, loop_top) +next_insn_in_loop (loop, insn) + const struct loop *loop; rtx insn; - rtx start; - rtx end; - rtx loop_top; { insn = NEXT_INSN (insn); - if (insn == end) + if (insn == loop->end) { - if (loop_top) + if (loop->top) /* Go to the top of the loop, and continue there. */ - insn = loop_top; + insn = loop->top; else /* We're done. */ insn = NULL_RTX; } - if (insn == start) + if (insn == loop->scan_start) /* We're done. */ insn = NULL_RTX; return insn; } -/* Optimize one loop whose start is LOOP_START and end is END. - LOOP_START is the NOTE_INSN_LOOP_BEG and END is the matching - NOTE_INSN_LOOP_END. - LOOP_CONT is the NOTE_INSN_LOOP_CONT. */ +/* Optimize one loop described by LOOP. */ /* ??? Could also move memory writes out of loops if the destination address is invariant, the source is invariant, the memory write is not volatile, @@ -632,35 +607,31 @@ next_insn_in_loop (insn, start, end, loop_top) write, then we can also mark the memory read as invariant. */ static void -scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) - rtx loop_start, end, loop_cont; - int unroll_p, bct_p; +scan_loop (loop, flags) + struct loop *loop; + int flags; { - register int i; + struct loop_info *loop_info = LOOP_INFO (loop); + struct loop_regs *regs = LOOP_REGS (loop); + int i; + rtx loop_start = loop->start; + rtx loop_end = loop->end; rtx p; /* 1 if we are scanning insns that could be executed zero times. */ int maybe_never = 0; /* 1 if we are scanning insns that might never be executed due to a subroutine call which might exit before they are reached. */ int call_passed = 0; - /* For a rotated loop that is entered near the bottom, - this is the label at the top. Otherwise it is zero. */ - rtx loop_top = 0; /* Jump insn that enters the loop, or 0 if control drops in. */ rtx loop_entry_jump = 0; - /* Place in the loop where control enters. */ - rtx scan_start; /* Number of insns in the loop. */ int insn_count; - int in_libcall = 0; int tem; - rtx temp; + rtx temp, update_start, update_end; /* The SET from an insn, if it is the only SET in the insn. */ rtx set, set1; /* Chain describing insns movable in current loop. */ - struct movable *movables = 0; - /* Last element in `movables' -- so we can add elements at the end. */ - struct movable *last_movable = 0; + struct loop_movables *movables = LOOP_MOVABLES (loop); /* Ratio of extra register life span we can justify for saving an instruction. More if loop doesn't call subroutines since in that case saving an insn makes more difference @@ -668,7 +639,11 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) int threshold; /* Nonzero if we are scanning instructions in a sub-loop. */ int loop_depth = 0; - int nregs; + + loop->top = 0; + + movables->head = 0; + movables->last = 0; /* Determine whether this loop starts with a jump down to a test at the end. This will occur for a small number of loops with a test @@ -683,35 +658,44 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) Note that if we mistakenly think that a loop is entered at the top when, in fact, it is entered at the exit test, the only effect will be slightly poorer optimization. Making the opposite error can generate - incorrect code. Since very few loops now start with a jump to the + incorrect code. Since very few loops now start with a jump to the exit test, the code here to detect that case is very conservative. */ for (p = NEXT_INSN (loop_start); - p != end - && GET_CODE (p) != CODE_LABEL && GET_RTX_CLASS (GET_CODE (p)) != 'i' + p != loop_end + && GET_CODE (p) != CODE_LABEL && ! INSN_P (p) && (GET_CODE (p) != NOTE || (NOTE_LINE_NUMBER (p) != NOTE_INSN_LOOP_BEG && NOTE_LINE_NUMBER (p) != NOTE_INSN_LOOP_END)); p = NEXT_INSN (p)) ; - scan_start = p; + loop->scan_start = p; + + /* If loop end is the end of the current function, then emit a + NOTE_INSN_DELETED after loop_end and set loop->sink to the dummy + note insn. This is the position we use when sinking insns out of + the loop. */ + if (NEXT_INSN (loop->end) != 0) + loop->sink = NEXT_INSN (loop->end); + else + loop->sink = emit_note_after (NOTE_INSN_DELETED, loop->end); /* Set up variables describing this loop. */ - prescan_loop (loop_start, end); - threshold = (loop_has_call ? 1 : 2) * (1 + n_non_fixed_regs); + prescan_loop (loop); + threshold = (loop_info->has_call ? 1 : 2) * (1 + n_non_fixed_regs); /* If loop has a jump before the first label, the true entry is the target of that jump. Start scan from there. - But record in LOOP_TOP the place where the end-test jumps + But record in LOOP->TOP the place where the end-test jumps back to so we can scan that after the end of the loop. */ if (GET_CODE (p) == JUMP_INSN) { loop_entry_jump = p; /* Loop entry must be unconditional jump (and not a RETURN) */ - if (simplejump_p (p) + if (any_uncondjump_p (p) && JUMP_LABEL (p) != 0 /* Check to see whether the jump actually jumps out of the loop (meaning it's no loop). @@ -719,76 +703,47 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) do {..} while (0). If this label was generated previously by loop, we can't tell anything about it and have to reject the loop. */ - && INSN_IN_RANGE_P (JUMP_LABEL (p), loop_start, end)) + && INSN_IN_RANGE_P (JUMP_LABEL (p), loop_start, loop_end)) { - loop_top = next_label (scan_start); - scan_start = JUMP_LABEL (p); + loop->top = next_label (loop->scan_start); + loop->scan_start = JUMP_LABEL (p); } } - /* If SCAN_START was an insn created by loop, we don't know its luid + /* If LOOP->SCAN_START was an insn created by loop, we don't know its luid as required by loop_reg_used_before_p. So skip such loops. (This - test may never be true, but it's best to play it safe.) + test may never be true, but it's best to play it safe.) Also, skip loops where we do not start scanning at a label. This test also rejects loops starting with a JUMP_INSN that failed the test above. */ - if (INSN_UID (scan_start) >= max_uid_for_loop - || GET_CODE (scan_start) != CODE_LABEL) + if (INSN_UID (loop->scan_start) >= max_uid_for_loop + || GET_CODE (loop->scan_start) != CODE_LABEL) { if (loop_dump_stream) fprintf (loop_dump_stream, "\nLoop from %d to %d is phony.\n\n", - INSN_UID (loop_start), INSN_UID (end)); + INSN_UID (loop_start), INSN_UID (loop_end)); return; } - /* Count number of times each reg is set during this loop. - Set VARRAY_CHAR (may_not_optimize, I) if it is not safe to move out - the setting of register I. Set VARRAY_RTX (reg_single_usage, I). */ - - /* Allocate extra space for REGS that might be created by - load_mems. We allocate a little extra slop as well, in the hopes - that even after the moving of movables creates some new registers - we won't have to reallocate these arrays. However, we do grow - the arrays, if necessary, in load_mems_recount_loop_regs_set. */ - nregs = max_reg_num () + loop_mems_idx + 16; - VARRAY_INT_INIT (set_in_loop, nregs, "set_in_loop"); - VARRAY_INT_INIT (n_times_set, nregs, "n_times_set"); - VARRAY_CHAR_INIT (may_not_optimize, nregs, "may_not_optimize"); - VARRAY_RTX_INIT (reg_single_usage, nregs, "reg_single_usage"); - - count_loop_regs_set (loop_top ? loop_top : loop_start, end, - may_not_optimize, reg_single_usage, &insn_count, nregs); - - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - { - VARRAY_CHAR (may_not_optimize, i) = 1; - VARRAY_INT (set_in_loop, i) = 1; - } - -#ifdef AVOID_CCMODE_COPIES - /* Don't try to move insns which set CC registers if we should not - create CCmode register copies. */ - for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) - if (GET_MODE_CLASS (GET_MODE (regno_reg_rtx[i])) == MODE_CC) - VARRAY_CHAR (may_not_optimize, i) = 1; -#endif - - bcopy ((char *) &set_in_loop->data, - (char *) &n_times_set->data, nregs * sizeof (int)); + /* Allocate extra space for REGs that might be created by load_mems. + We allocate a little extra slop as well, in the hopes that we + won't have to reallocate the regs array. */ + loop_regs_scan (loop, loop_info->mems_idx + 16); + insn_count = count_insns_in_loop (loop); if (loop_dump_stream) { fprintf (loop_dump_stream, "\nLoop from %d to %d: %d real insns.\n", - INSN_UID (loop_start), INSN_UID (end), insn_count); - if (loop_continue) + INSN_UID (loop_start), INSN_UID (loop_end), insn_count); + if (loop->cont) fprintf (loop_dump_stream, "Continue at insn %d.\n", - INSN_UID (loop_continue)); + INSN_UID (loop->cont)); } /* Scan through the loop finding insns that are safe to move. - Set set_in_loop negative for the reg being set, so that + Set REGS->ARRAY[I].SET_IN_LOOP negative for the reg I being set, so that this reg will be considered invariant for subsequent insns. We consider whether subsequent insns use the reg in deciding whether it is worth actually moving. @@ -800,21 +755,17 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) When MAYBE_NEVER is 0, all insns will be executed at least once so that is not a problem. */ - for (p = next_insn_in_loop (scan_start, scan_start, end, loop_top); + for (p = next_insn_in_loop (loop, loop->scan_start); p != NULL_RTX; - p = next_insn_in_loop (p, scan_start, end, loop_top)) + p = next_insn_in_loop (loop, p)) { - if (GET_RTX_CLASS (GET_CODE (p)) == 'i' - && find_reg_note (p, REG_LIBCALL, NULL_RTX)) - in_libcall = 1; - else if (GET_RTX_CLASS (GET_CODE (p)) == 'i' - && find_reg_note (p, REG_RETVAL, NULL_RTX)) - in_libcall = 0; - if (GET_CODE (p) == INSN && (set = single_set (p)) && GET_CODE (SET_DEST (set)) == REG - && ! VARRAY_CHAR (may_not_optimize, REGNO (SET_DEST (set)))) +#ifdef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED + && SET_DEST (set) != pic_offset_table_rtx +#endif + && ! regs->array[REGNO (SET_DEST (set))].may_not_optimize) { int tem1 = 0; int tem2 = 0; @@ -833,7 +784,7 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) temp = find_reg_note (p, REG_EQUIV, NULL_RTX); if (temp) src = XEXP (temp, 0), move_insn = 1; - else + else { temp = find_reg_note (p, REG_EQUAL, NULL_RTX); if (temp && CONSTANT_P (XEXP (temp, 0))) @@ -848,6 +799,18 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) } } + /* For parallels, add any possible uses to the depencies, as we can't move + the insn without resolving them first. */ + if (GET_CODE (PATTERN (p)) == PARALLEL) + { + for (i = 0; i < XVECLEN (PATTERN (p), 0); i++) + { + rtx x = XVECEXP (PATTERN (p), 0, i); + if (GET_CODE (x) == USE) + dependencies = gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0), dependencies); + } + } + /* Don't try to optimize a register that was made by loop-optimization for an inner loop. We don't know its life-span, so we can't compute the benefit. */ @@ -858,9 +821,9 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) something after this point in the loop might depend on its value before the set). */ ! reg_in_basic_block_p (p, SET_DEST (set)) - /* And the set is not guaranteed to be executed one + /* And the set is not guaranteed to be executed once the loop starts, or the value before the set is - needed before the set occurs... + needed before the set occurs... ??? Note we have quadratic behaviour here, mitigated by the fact that the previous test will often fail for @@ -868,23 +831,21 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) each time for register usage, we should build tables of the register usage and use them here instead. */ && (maybe_never - || loop_reg_used_before_p (set, p, loop_start, - scan_start, end))) - /* It is unsafe to move the set. + || loop_reg_used_before_p (loop, set, p))) + /* It is unsafe to move the set. This code used to consider it OK to move a set of a variable which was not created by the user and not used in an exit test. That behavior is incorrect and was removed. */ ; - else if ((tem = invariant_p (src)) + else if ((tem = loop_invariant_p (loop, src)) && (dependencies == 0 - || (tem2 = invariant_p (dependencies)) != 0) - && (VARRAY_INT (set_in_loop, - REGNO (SET_DEST (set))) == 1 + || (tem2 = loop_invariant_p (loop, dependencies)) != 0) + && (regs->array[REGNO (SET_DEST (set))].set_in_loop == 1 || (tem1 - = consec_sets_invariant_p - (SET_DEST (set), - VARRAY_INT (set_in_loop, REGNO (SET_DEST (set))), + = consec_sets_invariant_p + (loop, SET_DEST (set), + regs->array[REGNO (SET_DEST (set))].set_in_loop, p))) /* If the insn can cause a trap (such as divide by zero), can't move it unless it's guaranteed to be executed @@ -894,33 +855,33 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) && ! ((maybe_never || call_passed) && may_trap_p (src))) { - register struct movable *m; - register int regno = REGNO (SET_DEST (set)); + struct movable *m; + int regno = REGNO (SET_DEST (set)); /* A potential lossage is where we have a case where two insns can be combined as long as they are both in the loop, but we move one of them outside the loop. For large loops, this can lose. The most common case of this is the address - of a function being called. + of a function being called. Therefore, if this register is marked as being used exactly once if we are in a loop with calls (a "large loop"), see if we can replace the usage of this register with the source - of this SET. If we can, delete this insn. + of this SET. If we can, delete this insn. Don't do this if P has a REG_RETVAL note or if we have SMALL_REGISTER_CLASSES and SET_SRC is a hard register. */ - if (loop_has_call - && VARRAY_RTX (reg_single_usage, regno) != 0 - && VARRAY_RTX (reg_single_usage, regno) != const0_rtx + if (loop_info->has_call + && regs->array[regno].single_usage != 0 + && regs->array[regno].single_usage != const0_rtx && REGNO_FIRST_UID (regno) == INSN_UID (p) && (REGNO_LAST_UID (regno) - == INSN_UID (VARRAY_RTX (reg_single_usage, regno))) - && VARRAY_INT (set_in_loop, regno) == 1 + == INSN_UID (regs->array[regno].single_usage)) + && regs->array[regno].set_in_loop == 1 + && GET_CODE (SET_SRC (set)) != ASM_OPERANDS && ! side_effects_p (SET_SRC (set)) && ! find_reg_note (p, REG_RETVAL, NULL_RTX) - && ! find_reg_note (p, REG_LABEL, NULL_RTX) && (! SMALL_REGISTER_CLASSES || (! (GET_CODE (SET_SRC (set)) == REG && REGNO (SET_SRC (set)) < FIRST_PSEUDO_REGISTER))) @@ -928,37 +889,32 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) a call-clobbered register and the life of REGNO might span a call. */ && ! modified_between_p (SET_SRC (set), p, - VARRAY_RTX - (reg_single_usage, regno)) - && no_labels_between_p (p, VARRAY_RTX (reg_single_usage, regno)) + regs->array[regno].single_usage) + && no_labels_between_p (p, regs->array[regno].single_usage) && validate_replace_rtx (SET_DEST (set), SET_SRC (set), - VARRAY_RTX - (reg_single_usage, regno))) + regs->array[regno].single_usage)) { /* Replace any usage in a REG_EQUAL note. Must copy the new source, so that we don't get rtx sharing between the SET_SOURCE and REG_NOTES of insn p. */ - REG_NOTES (VARRAY_RTX (reg_single_usage, regno)) - = replace_rtx (REG_NOTES (VARRAY_RTX - (reg_single_usage, regno)), + REG_NOTES (regs->array[regno].single_usage) + = replace_rtx (REG_NOTES (regs->array[regno].single_usage), SET_DEST (set), copy_rtx (SET_SRC (set))); - - PUT_CODE (p, NOTE); - NOTE_LINE_NUMBER (p) = NOTE_INSN_DELETED; - NOTE_SOURCE_FILE (p) = 0; - VARRAY_INT (set_in_loop, regno) = 0; + + delete_insn (p); + for (i = 0; i < LOOP_REGNO_NREGS (regno, SET_DEST (set)); i++) + regs->array[regno+i].set_in_loop = 0; continue; } - m = (struct movable *) alloca (sizeof (struct movable)); + m = (struct movable *) xmalloc (sizeof (struct movable)); m->next = 0; m->insn = p; m->set_src = src; m->dependencies = dependencies; m->set_dest = SET_DEST (set); m->force = 0; - m->consec = VARRAY_INT (set_in_loop, - REGNO (SET_DEST (set))) - 1; + m->consec = regs->array[REGNO (SET_DEST (set))].set_in_loop - 1; m->done = 0; m->forces = 0; m->partial = 0; @@ -967,24 +923,20 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) m->is_equiv = (find_reg_note (p, REG_EQUIV, NULL_RTX) != 0); m->savemode = VOIDmode; m->regno = regno; - /* Set M->cond if either invariant_p or consec_sets_invariant_p - returned 2 (only conditionally invariant). */ + /* Set M->cond if either loop_invariant_p + or consec_sets_invariant_p returned 2 + (only conditionally invariant). */ m->cond = ((tem | tem1 | tem2) > 1); - m->global = (uid_luid[REGNO_LAST_UID (regno)] > INSN_LUID (end) - || uid_luid[REGNO_FIRST_UID (regno)] < INSN_LUID (loop_start)); + m->global = LOOP_REG_GLOBAL_P (loop, regno); m->match = 0; - m->lifetime = (uid_luid[REGNO_LAST_UID (regno)] - - uid_luid[REGNO_FIRST_UID (regno)]); - m->savings = VARRAY_INT (n_times_set, regno); + m->lifetime = LOOP_REG_LIFETIME (loop, regno); + m->savings = regs->array[regno].n_times_set; if (find_reg_note (p, REG_RETVAL, NULL_RTX)) m->savings += libcall_benefit (p); - VARRAY_INT (set_in_loop, regno) = move_insn ? -2 : -1; + for (i = 0; i < LOOP_REGNO_NREGS (regno, SET_DEST (set)); i++) + regs->array[regno+i].set_in_loop = move_insn ? -2 : -1; /* Add M to the end of the chain MOVABLES. */ - if (movables == 0) - movables = m; - else - last_movable->next = m; - last_movable = m; + loop_movables_add (movables, m); if (m->consec > 0) { @@ -1036,11 +988,11 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) == SET_DEST (set)) && !reg_mentioned_p (SET_DEST (set), SET_SRC (set1))) { - register int regno = REGNO (SET_DEST (set)); - if (VARRAY_INT (set_in_loop, regno) == 2) + int regno = REGNO (SET_DEST (set)); + if (regs->array[regno].set_in_loop == 2) { - register struct movable *m; - m = (struct movable *) alloca (sizeof (struct movable)); + struct movable *m; + m = (struct movable *) xmalloc (sizeof (struct movable)); m->next = 0; m->insn = p; m->set_dest = SET_DEST (set); @@ -1071,12 +1023,9 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) INSN_LUID and hence must make a conservative assumption. */ m->global = (INSN_UID (p) >= max_uid_for_loop - || (uid_luid[REGNO_LAST_UID (regno)] - > INSN_LUID (end)) - || (uid_luid[REGNO_FIRST_UID (regno)] - < INSN_LUID (p)) + || LOOP_REG_GLOBAL_P (loop, regno) || (labels_in_range_p - (p, uid_luid[REGNO_FIRST_UID (regno)]))); + (p, REGNO_FIRST_LUID (regno)))); if (maybe_never && m->global) m->savemode = GET_MODE (SET_SRC (set1)); else @@ -1084,24 +1033,19 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) m->regno = regno; m->cond = 0; m->match = 0; - m->lifetime = (uid_luid[REGNO_LAST_UID (regno)] - - uid_luid[REGNO_FIRST_UID (regno)]); + m->lifetime = LOOP_REG_LIFETIME (loop, regno); m->savings = 1; - VARRAY_INT (set_in_loop, regno) = -1; + for (i = 0; i < LOOP_REGNO_NREGS (regno, SET_DEST (set)); i++) + regs->array[regno+i].set_in_loop = -1; /* Add M to the end of the chain MOVABLES. */ - if (movables == 0) - movables = m; - else - last_movable->next = m; - last_movable = m; + loop_movables_add (movables, m); } } } /* Past a call insn, we get to insns which might not be executed because the call might exit. This matters for insns that trap. - Call insns inside a REG_LIBCALL/REG_RETVAL block always return, - so they don't count. */ - else if (GET_CODE (p) == CALL_INSN && ! in_libcall) + Constant and pure call insns always return, so they don't count. */ + else if (GET_CODE (p) == CALL_INSN && ! CONST_OR_PURE_CALL_P (p)) call_passed = 1; /* Past a label or a jump, we get to insns for which we can't count on whether or how many times they will be @@ -1114,10 +1058,10 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) beginning, don't set maybe_never for that. This must be an unconditional jump, otherwise the code at the top of the loop might never be executed. Unconditional jumps are - followed a by barrier then loop end. */ - && ! (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) == loop_top - && NEXT_INSN (NEXT_INSN (p)) == end - && simplejump_p (p))) + followed by a barrier then the loop_end. */ + && ! (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) == loop->top + && NEXT_INSN (NEXT_INSN (p)) == loop_end + && any_uncondjump_p (p))) maybe_never = 1; else if (GET_CODE (p) == NOTE) { @@ -1149,40 +1093,65 @@ scan_loop (loop_start, end, loop_cont, unroll_p, bct_p) through the `match' field, and add the priorities of them all together as the priority of the first. */ - combine_movables (movables, nregs); - + combine_movables (movables, regs); + /* Now consider each movable insn to decide whether it is worth moving. - Store 0 in set_in_loop for each reg that is moved. + Store 0 in regs->array[I].set_in_loop for each reg I that is moved. Generally this increases code size, so do not move moveables when optimizing for code size. */ if (! optimize_size) - move_movables (movables, threshold, - insn_count, loop_start, end, nregs); + move_movables (loop, movables, threshold, insn_count); /* Now candidates that still are negative are those not moved. - Change set_in_loop to indicate that those are not actually invariant. */ - for (i = 0; i < nregs; i++) - if (VARRAY_INT (set_in_loop, i) < 0) - VARRAY_INT (set_in_loop, i) = VARRAY_INT (n_times_set, i); + Change regs->array[I].set_in_loop to indicate that those are not actually + invariant. */ + for (i = 0; i < regs->num; i++) + if (regs->array[i].set_in_loop < 0) + regs->array[i].set_in_loop = regs->array[i].n_times_set; /* Now that we've moved some things out of the loop, we might be able to hoist even more memory references. */ - load_mems_and_recount_loop_regs_set (scan_start, end, loop_top, - loop_start, &insn_count); + load_mems (loop); + + /* Recalculate regs->array if load_mems has created new registers. */ + if (max_reg_num () > regs->num) + loop_regs_scan (loop, 0); + + for (update_start = loop_start; + PREV_INSN (update_start) + && GET_CODE (PREV_INSN (update_start)) != CODE_LABEL; + update_start = PREV_INSN (update_start)) + ; + update_end = NEXT_INSN (loop_end); + + reg_scan_update (update_start, update_end, loop_max_reg); + loop_max_reg = max_reg_num (); if (flag_strength_reduce) { - the_movables = movables; - strength_reduce (scan_start, end, loop_top, - insn_count, loop_start, end, loop_cont, unroll_p, bct_p); + if (update_end && GET_CODE (update_end) == CODE_LABEL) + /* Ensure our label doesn't go away. */ + LABEL_NUSES (update_end)++; + + strength_reduce (loop, flags); + + reg_scan_update (update_start, update_end, loop_max_reg); + loop_max_reg = max_reg_num (); + + if (update_end && GET_CODE (update_end) == CODE_LABEL + && --LABEL_NUSES (update_end) == 0) + delete_related_insns (update_end); } - VARRAY_FREE (reg_single_usage); - VARRAY_FREE (set_in_loop); - VARRAY_FREE (n_times_set); - VARRAY_FREE (may_not_optimize); + + /* The movable information is required for strength reduction. */ + loop_movables_free (movables); + + free (regs->array); + regs->array = 0; + regs->num = 0; } /* Add elements to *OUTPUT to record all the pseudo-regs @@ -1194,7 +1163,7 @@ record_excess_regs (in_this, not_in_this, output) rtx *output; { enum rtx_code code; - char *fmt; + const char *fmt; int i; code = GET_CODE (in_this); @@ -1215,7 +1184,7 @@ record_excess_regs (in_this, not_in_this, output) && ! reg_mentioned_p (in_this, not_in_this)) *output = gen_rtx_EXPR_LIST (VOIDmode, in_this, *output); return; - + default: break; } @@ -1269,7 +1238,7 @@ libcall_other_reg (insn, equiv) /* Return 1 if all uses of REG are between INSN and the end of the basic block. */ -static int +static int reg_in_basic_block_p (insn, reg) rtx insn, reg; { @@ -1305,14 +1274,18 @@ reg_in_basic_block_p (insn, reg) case BARRIER: /* It's the end of the basic block, so we lose. */ return 0; - + default: break; } } - /* The "last use" doesn't follow the "first use"?? */ - abort (); + /* The "last use" that was recorded can't be found after the first + use. This can happen when the last use was deleted while + processing an inner loop, this inner loop was then completely + unrolled, and the outer loop is always exited after the inner loop, + so that everything after the first use becomes a single basic block. */ + return 1; } /* Compute the benefit of eliminating the insns in the block whose @@ -1353,13 +1326,14 @@ skip_consec_insns (insn, count) rtx temp; /* If first insn of libcall sequence, skip to end. */ - /* Do this at start of loop, since INSN is guaranteed to + /* Do this at start of loop, since INSN is guaranteed to be an insn here. */ if (GET_CODE (insn) != NOTE && (temp = find_reg_note (insn, REG_LIBCALL, NULL_RTX))) insn = XEXP (temp, 0); - do insn = NEXT_INSN (insn); + do + insn = NEXT_INSN (insn); while (GET_CODE (insn) == NOTE); } @@ -1373,11 +1347,11 @@ skip_consec_insns (insn, count) static void ignore_some_movables (movables) - struct movable *movables; + struct loop_movables *movables; { - register struct movable *m, *m1; + struct movable *m, *m1; - for (m = movables; m; m = m->next) + for (m = movables->head; m; m = m->next) { /* Is this a movable for the value of a libcall? */ rtx note = find_reg_note (m->insn, REG_RETVAL, NULL_RTX); @@ -1391,12 +1365,12 @@ ignore_some_movables (movables) explicitly check each insn in the libcall (since invariant libcalls aren't that common). */ for (insn = XEXP (note, 0); insn != m->insn; insn = NEXT_INSN (insn)) - for (m1 = movables; m1 != m; m1 = m1->next) + for (m1 = movables->head; m1 != m; m1 = m1->next) if (m1->insn == insn) m1->done = 1; } } -} +} /* For each movable insn, see if the reg that it loads leads when it dies right into another conditionally movable insn. @@ -1405,10 +1379,11 @@ ignore_some_movables (movables) static void force_movables (movables) - struct movable *movables; + struct loop_movables *movables; { - register struct movable *m, *m1; - for (m1 = movables; m1; m1 = m1->next) + struct movable *m, *m1; + + for (m1 = movables->head; m1; m1 = m1->next) /* Omit this if moving just the (SET (REG) 0) of a zero-extend. */ if (!m1->partial && !m1->done) { @@ -1443,31 +1418,36 @@ force_movables (movables) one register. */ static void -combine_movables (movables, nregs) - struct movable *movables; - int nregs; +combine_movables (movables, regs) + struct loop_movables *movables; + struct loop_regs *regs; { - register struct movable *m; - char *matched_regs = (char *) alloca (nregs); + struct movable *m; + char *matched_regs = (char *) xmalloc (regs->num); enum machine_mode mode; /* Regs that are set more than once are not allowed to match or be matched. I'm no longer sure why not. */ /* Perhaps testing m->consec_sets would be more appropriate here? */ - for (m = movables; m; m = m->next) - if (m->match == 0 && VARRAY_INT (n_times_set, m->regno) == 1 && !m->partial) + for (m = movables->head; m; m = m->next) + if (m->match == 0 && regs->array[m->regno].n_times_set == 1 + && !m->partial) { - register struct movable *m1; + struct movable *m1; int regno = m->regno; - bzero (matched_regs, nregs); + memset (matched_regs, 0, regs->num); matched_regs[regno] = 1; /* We want later insns to match the first one. Don't make the first one match any later ones. So start this loop at m->next. */ for (m1 = m->next; m1; m1 = m1->next) - if (m != m1 && m1->match == 0 && VARRAY_INT (n_times_set, m1->regno) == 1 + /* ??? HACK! move_movables does not verify that the replacement + is valid, which can have disasterous effects with hard regs + and match_dup. Turn combination off for now. */ + if (0 && m != m1 && m1->match == 0 + && regs->array[m1->regno].n_times_set == 1 /* A reg used outside the loop mustn't be eliminated. */ && !m1->global /* A reg used for zero-extending mustn't be eliminated. */ @@ -1491,7 +1471,7 @@ combine_movables (movables, nregs) && ((GET_CODE (m1->set_src) == REG && matched_regs[REGNO (m1->set_src)]) || rtx_equal_for_loop_p (m->set_src, m1->set_src, - movables)))) + movables, regs)))) && ((m->dependencies == m1->dependencies) || rtx_equal_p (m->dependencies, m1->dependencies))) { @@ -1510,36 +1490,37 @@ combine_movables (movables, nregs) for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; mode = GET_MODE_WIDER_MODE (mode)) { - register struct movable *m0 = 0; + struct movable *m0 = 0; /* Combine all the registers for extension from mode MODE. Don't combine any that are used outside this loop. */ - for (m = movables; m; m = m->next) + for (m = movables->head; m; m = m->next) if (m->partial && ! m->global && mode == GET_MODE (SET_SRC (PATTERN (NEXT_INSN (m->insn))))) { - register struct movable *m1; - int first = uid_luid[REGNO_FIRST_UID (m->regno)]; - int last = uid_luid[REGNO_LAST_UID (m->regno)]; + struct movable *m1; + + int first = REGNO_FIRST_LUID (m->regno); + int last = REGNO_LAST_LUID (m->regno); if (m0 == 0) { /* First one: don't check for overlap, just record it. */ m0 = m; - continue; + continue; } /* Make sure they extend to the same mode. (Almost always true.) */ if (GET_MODE (m->set_dest) != GET_MODE (m0->set_dest)) - continue; + continue; /* We already have one: check for overlap with those already combined together. */ - for (m1 = movables; m1 != m; m1 = m1->next) + for (m1 = movables->head; m1 != m; m1 = m1->next) if (m1 == m0 || (m1->partial && m1->match == m0)) - if (! (uid_luid[REGNO_FIRST_UID (m1->regno)] > last - || uid_luid[REGNO_LAST_UID (m1->regno)] < first)) + if (! (REGNO_FIRST_LUID (m1->regno) > last + || REGNO_LAST_LUID (m1->regno) < first)) goto overlap; /* No overlap: we can combine this with the others. */ @@ -1548,27 +1529,49 @@ combine_movables (movables, nregs) m->done = 1; m->match = m0; - overlap: ; + overlap: + ; } } + + /* Clean up. */ + free (matched_regs); } + +/* Returns the number of movable instructions in LOOP that were not + moved outside the loop. */ + +static int +num_unmoved_movables (loop) + const struct loop *loop; +{ + int num = 0; + struct movable *m; + + for (m = LOOP_MOVABLES (loop)->head; m; m = m->next) + if (!m->done) + ++num; + + return num; +} + /* Return 1 if regs X and Y will become the same if moved. */ static int regs_match_p (x, y, movables) rtx x, y; - struct movable *movables; + struct loop_movables *movables; { - int xn = REGNO (x); - int yn = REGNO (y); + unsigned int xn = REGNO (x); + unsigned int yn = REGNO (y); struct movable *mx, *my; - for (mx = movables; mx; mx = mx->next) + for (mx = movables->head; mx; mx = mx->next) if (mx->regno == xn) break; - for (my = movables; my; my = my->next) + for (my = movables->head; my; my = my->next) if (my->regno == yn) break; @@ -1585,15 +1588,16 @@ regs_match_p (x, y, movables) equivalent constant, consider them equal. */ static int -rtx_equal_for_loop_p (x, y, movables) +rtx_equal_for_loop_p (x, y, movables, regs) rtx x, y; - struct movable *movables; + struct loop_movables *movables; + struct loop_regs *regs; { - register int i; - register int j; - register struct movable *m; - register enum rtx_code code; - register char *fmt; + int i; + int j; + struct movable *m; + enum rtx_code code; + const char *fmt; if (x == y) return 1; @@ -1604,18 +1608,18 @@ rtx_equal_for_loop_p (x, y, movables) /* If we have a register and a constant, they may sometimes be equal. */ - if (GET_CODE (x) == REG && VARRAY_INT (set_in_loop, REGNO (x)) == -2 + if (GET_CODE (x) == REG && regs->array[REGNO (x)].set_in_loop == -2 && CONSTANT_P (y)) { - for (m = movables; m; m = m->next) + for (m = movables->head; m; m = m->next) if (m->move_insn && m->regno == REGNO (x) && rtx_equal_p (m->set_src, y)) return 1; } - else if (GET_CODE (y) == REG && VARRAY_INT (set_in_loop, REGNO (y)) == -2 + else if (GET_CODE (y) == REG && regs->array[REGNO (y)].set_in_loop == -2 && CONSTANT_P (x)) { - for (m = movables; m; m = m->next) + for (m = movables->head; m; m = m->next) if (m->move_insn && m->regno == REGNO (y) && rtx_equal_p (m->set_src, x)) return 1; @@ -1665,12 +1669,14 @@ rtx_equal_for_loop_p (x, y, movables) /* And the corresponding elements must match. */ for (j = 0; j < XVECLEN (x, i); j++) - if (rtx_equal_for_loop_p (XVECEXP (x, i, j), XVECEXP (y, i, j), movables) == 0) + if (rtx_equal_for_loop_p (XVECEXP (x, i, j), XVECEXP (y, i, j), + movables, regs) == 0) return 0; break; case 'e': - if (rtx_equal_for_loop_p (XEXP (x, i), XEXP (y, i), movables) == 0) + if (rtx_equal_for_loop_p (XEXP (x, i), XEXP (y, i), movables, regs) + == 0) return 0; break; @@ -1697,7 +1703,8 @@ rtx_equal_for_loop_p (x, y, movables) } /* If X contains any LABEL_REF's, add REG_LABEL notes for them to all - insns in INSNS which use thet reference. */ + insns in INSNS which use the reference. LABEL_NUSES for CODE_LABEL + references is incremented once for each added note. */ static void add_label_notes (x, insns) @@ -1706,7 +1713,7 @@ add_label_notes (x, insns) { enum rtx_code code = GET_CODE (x); int i, j; - char *fmt; + const char *fmt; rtx insn; if (code == LABEL_REF && !LABEL_REF_NONLOCAL_P (x)) @@ -1718,8 +1725,12 @@ add_label_notes (x, insns) mark_jump_label for additional information). */ for (insn = insns; insn; insn = NEXT_INSN (insn)) if (reg_mentioned_p (XEXP (x, 0), insn)) - REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_LABEL, XEXP (x, 0), - REG_NOTES (insn)); + { + REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, XEXP (x, 0), + REG_NOTES (insn)); + if (LABEL_P (XEXP (x, 0))) + LABEL_NUSES (XEXP (x, 0))++; + } } fmt = GET_RTX_FORMAT (code); @@ -1738,29 +1749,26 @@ add_label_notes (x, insns) other throughout. */ static void -move_movables (movables, threshold, insn_count, loop_start, end, nregs) - struct movable *movables; +move_movables (loop, movables, threshold, insn_count) + struct loop *loop; + struct loop_movables *movables; int threshold; int insn_count; - rtx loop_start; - rtx end; - int nregs; { + struct loop_regs *regs = LOOP_REGS (loop); + int nregs = regs->num; rtx new_start = 0; - register struct movable *m; - register rtx p; + struct movable *m; + rtx p; + rtx loop_start = loop->start; + rtx loop_end = loop->end; /* Map of pseudo-register replacements to handle combining when we move several insns that load the same value into different pseudo-registers. */ - rtx *reg_map = (rtx *) alloca (nregs * sizeof (rtx)); - char *already_moved = (char *) alloca (nregs); - - bzero (already_moved, nregs); - bzero ((char *) reg_map, nregs * sizeof (rtx)); + rtx *reg_map = (rtx *) xcalloc (nregs, sizeof (rtx)); + char *already_moved = (char *) xcalloc (nregs, sizeof (char)); - num_movables = 0; - - for (m = movables; m; m = m->next) + for (m = movables->head; m; m = m->next) { /* Describe this movable insn. */ @@ -1788,25 +1796,22 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) INSN_UID (m->forces->insn)); } - /* Count movables. Value used in heuristics in strength_reduce. */ - num_movables++; - /* Ignore the insn if it's already done (it matched something else). Otherwise, see if it is now safe to move. */ if (!m->done && (! m->cond - || (1 == invariant_p (m->set_src) + || (1 == loop_invariant_p (loop, m->set_src) && (m->dependencies == 0 - || 1 == invariant_p (m->dependencies)) + || 1 == loop_invariant_p (loop, m->dependencies)) && (m->consec == 0 - || 1 == consec_sets_invariant_p (m->set_dest, + || 1 == consec_sets_invariant_p (loop, m->set_dest, m->consec + 1, m->insn)))) && (! m->forces || m->forces->done)) { - register int regno; - register rtx p; + int regno; + rtx p; int savings = m->savings; /* We have an insn that is safe to move. @@ -1818,7 +1823,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) if (loop_dump_stream) fprintf (loop_dump_stream, "savings %d ", savings); - if (moved_once[regno] && loop_dump_stream) + if (regs->array[regno].moved_once && loop_dump_stream) fprintf (loop_dump_stream, "halved since already moved "); /* An insn MUST be moved if we already moved something else @@ -1837,13 +1842,13 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) if (already_moved[regno] || flag_move_all_movables || (threshold * savings * m->lifetime) >= - (moved_once[regno] ? insn_count * 2 : insn_count) + (regs->array[regno].moved_once ? insn_count * 2 : insn_count) || (m->forces && m->forces->done - && VARRAY_INT (n_times_set, m->forces->regno) == 1)) + && regs->array[m->forces->regno].n_times_set == 1)) { int count; - register struct movable *m1; - rtx first; + struct movable *m1; + rtx first = NULL_RTX; /* Now move the insns that set the reg. */ @@ -1858,7 +1863,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) for (m1 = m; m1->match; m1 = m1->match); newpat = gen_move_insn (SET_DEST (PATTERN (m->insn)), SET_DEST (PATTERN (m1->insn))); - i1 = emit_insn_before (newpat, loop_start); + i1 = loop_insn_hoist (loop, newpat); /* Mark the moved, invariant reg as being allowed to share a hard reg with the other matching invariant. */ @@ -1882,7 +1887,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) the move insn before the loop. */ else if (m->move_insn) { - rtx i1, temp; + rtx i1, temp, seq; for (count = m->consec; count >= 0; count--) { @@ -1919,15 +1924,16 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) start_sequence (); emit_move_insn (m->set_dest, m->set_src); temp = get_insns (); + seq = gen_sequence (); end_sequence (); add_label_notes (m->set_src, temp); - i1 = emit_insns_before (temp, loop_start); + i1 = loop_insn_hoist (loop, seq); if (! find_reg_note (i1, REG_EQUAL, NULL_RTX)) - REG_NOTES (i1) - = gen_rtx_EXPR_LIST (m->is_equiv ? REG_EQUIV : REG_EQUAL, - m->set_src, REG_NOTES (i1)); + set_unique_reg_note (i1, + m->is_equiv ? REG_EQUIV : REG_EQUAL, + m->set_src); if (loop_dump_stream) fprintf (loop_dump_stream, " moved to %d", INSN_UID (i1)); @@ -1942,7 +1948,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) rtx i1, temp; /* If first insn of libcall sequence, skip to end. */ - /* Do this at start of loop, since p is guaranteed to + /* Do this at start of loop, since p is guaranteed to be an insn here. */ if (GET_CODE (p) != NOTE && (temp = find_reg_note (p, REG_LIBCALL, NULL_RTX))) @@ -1979,7 +1985,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) && GET_CODE (PATTERN (next)) == USE) && GET_CODE (next) != NOTE) break; - + /* If that is the call, this may be the insn that loads the function address. @@ -2009,13 +2015,13 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) if (GET_CODE (temp) == CALL_INSN && fn_address != 0 && reg_referenced_p (fn_reg, body)) - emit_insn_after (gen_move_insn (fn_reg, - fn_address), - fn_address_insn); + loop_insn_emit_after (loop, 0, fn_address_insn, + gen_move_insn + (fn_reg, fn_address)); if (GET_CODE (temp) == CALL_INSN) { - i1 = emit_call_insn_before (body, loop_start); + i1 = loop_call_insn_hoist (loop, body); /* Because the USAGE information potentially contains objects other than hard registers we need to copy it. */ @@ -2024,12 +2030,13 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) = copy_rtx (CALL_INSN_FUNCTION_USAGE (temp)); } else - i1 = emit_insn_before (body, loop_start); + i1 = loop_insn_hoist (loop, body); if (first == 0) first = i1; if (temp == fn_address_insn) fn_address_insn = i1; REG_NOTES (i1) = REG_NOTES (temp); + REG_NOTES (temp) = NULL; delete_insn (temp); } if (new_start == 0) @@ -2043,10 +2050,10 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) rtx reg = m->set_dest; rtx sequence; rtx tem; - + start_sequence (); - tem = expand_binop - (GET_MODE (reg), and_optab, reg, + tem = expand_simple_binop + (GET_MODE (reg), AND, reg, GEN_INT ((((HOST_WIDE_INT) 1 << GET_MODE_BITSIZE (m->savemode))) - 1), @@ -2057,11 +2064,11 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) emit_move_insn (reg, tem); sequence = gen_sequence (); end_sequence (); - i1 = emit_insn_before (sequence, loop_start); + i1 = loop_insn_hoist (loop, sequence); } else if (GET_CODE (p) == CALL_INSN) { - i1 = emit_call_insn_before (PATTERN (p), loop_start); + i1 = loop_call_insn_hoist (loop, PATTERN (p)); /* Because the USAGE information potentially contains objects other than hard registers we need to copy it. */ @@ -2071,37 +2078,38 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) } else if (count == m->consec && m->move_insn_first) { + rtx seq; /* The SET_SRC might not be invariant, so we must use the REG_EQUAL note. */ start_sequence (); emit_move_insn (m->set_dest, m->set_src); temp = get_insns (); + seq = gen_sequence (); end_sequence (); add_label_notes (m->set_src, temp); - i1 = emit_insns_before (temp, loop_start); + i1 = loop_insn_hoist (loop, seq); if (! find_reg_note (i1, REG_EQUAL, NULL_RTX)) - REG_NOTES (i1) - = gen_rtx_EXPR_LIST ((m->is_equiv ? REG_EQUIV - : REG_EQUAL), - m->set_src, REG_NOTES (i1)); + set_unique_reg_note (i1, m->is_equiv ? REG_EQUIV + : REG_EQUAL, m->set_src); } else - i1 = emit_insn_before (PATTERN (p), loop_start); + i1 = loop_insn_hoist (loop, PATTERN (p)); if (REG_NOTES (i1) == 0) { REG_NOTES (i1) = REG_NOTES (p); + REG_NOTES (p) = NULL; /* If there is a REG_EQUAL note present whose value is not loop invariant, then delete it, since it may cause problems with later optimization passes. It is possible for cse to create such notes like this as a result of record_jump_cond. */ - + if ((temp = find_reg_note (i1, REG_EQUAL, NULL_RTX)) - && ! invariant_p (XEXP (temp, 0))) + && ! loop_invariant_p (loop, XEXP (temp, 0))) remove_note (i1, temp); } @@ -2145,11 +2153,15 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) already_moved[regno] = 1; /* This reg has been moved out of one loop. */ - moved_once[regno] = 1; + regs->array[regno].moved_once = 1; /* The reg set here is now invariant. */ if (! m->partial) - VARRAY_INT (set_in_loop, regno) = 0; + { + int i; + for (i = 0; i < LOOP_REGNO_NREGS (regno, m->set_dest); i++) + regs->array[regno+i].set_in_loop = 0; + } m->done = 1; @@ -2157,18 +2169,18 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) to say it lives at least the full length of this loop. This will help guide optimizations in outer loops. */ - if (uid_luid[REGNO_FIRST_UID (regno)] > INSN_LUID (loop_start)) + if (REGNO_FIRST_LUID (regno) > INSN_LUID (loop_start)) /* This is the old insn before all the moved insns. We can't use the moved insn because it is out of range in uid_luid. Only the old insns have luids. */ REGNO_FIRST_UID (regno) = INSN_UID (loop_start); - if (uid_luid[REGNO_LAST_UID (regno)] < INSN_LUID (end)) - REGNO_LAST_UID (regno) = INSN_UID (end); + if (REGNO_LAST_LUID (regno) < INSN_LUID (loop_end)) + REGNO_LAST_UID (regno) = INSN_UID (loop_end); /* Combine with this moved insn any other matching movables. */ if (! m->partial) - for (m1 = movables; m1; m1 = m1->next) + for (m1 = movables->head; m1; m1 = m1->next) if (m1->match == m) { rtx temp; @@ -2176,28 +2188,31 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) /* Schedule the reg loaded by M1 for replacement so that shares the reg of M. If the modes differ (only possible in restricted - circumstances, make a SUBREG. */ + circumstances, make a SUBREG. + + Note this assumes that the target dependent files + treat REG and SUBREG equally, including within + GO_IF_LEGITIMATE_ADDRESS and in all the + predicates since we never verify that replacing the + original register with a SUBREG results in a + recognizable insn. */ if (GET_MODE (m->set_dest) == GET_MODE (m1->set_dest)) reg_map[m1->regno] = m->set_dest; else reg_map[m1->regno] = gen_lowpart_common (GET_MODE (m1->set_dest), m->set_dest); - + /* Get rid of the matching insn and prevent further processing of it. */ m1->done = 1; - /* if library call, delete all insn except last, which - is deleted below */ + /* if library call, delete all insns. */ if ((temp = find_reg_note (m1->insn, REG_RETVAL, NULL_RTX))) - { - for (temp = XEXP (temp, 0); temp != m1->insn; - temp = NEXT_INSN (temp)) - delete_insn (temp); - } - delete_insn (m1->insn); + delete_insn_chain (XEXP (temp, 0), m1->insn); + else + delete_insn (m1->insn); /* Any other movable that loads the same register MUST be moved. */ @@ -2206,7 +2221,13 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) /* The reg merged here is now invariant, if the reg it matches is invariant. */ if (! m->partial) - VARRAY_INT (set_in_loop, m1->regno) = 0; + { + int i; + for (i = 0; + i < LOOP_REGNO_NREGS (regno, m1->set_dest); + i++) + regs->array[m1->regno+i].set_in_loop = 0; + } } } else if (loop_dump_stream) @@ -2224,7 +2245,7 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) /* Go through all the instructions in the loop, making all the register substitutions scheduled in REG_MAP. */ - for (p = new_start; p != end; p = NEXT_INSN (p)) + for (p = new_start; p != loop_end; p = NEXT_INSN (p)) if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN || GET_CODE (p) == CALL_INSN) { @@ -2232,6 +2253,38 @@ move_movables (movables, threshold, insn_count, loop_start, end, nregs) replace_regs (REG_NOTES (p), reg_map, nregs, 0); INSN_CODE (p) = -1; } + + /* Clean up. */ + free (reg_map); + free (already_moved); +} + + +static void +loop_movables_add (movables, m) + struct loop_movables *movables; + struct movable *m; +{ + if (movables->head == 0) + movables->head = m; + else + movables->last->next = m; + movables->last = m; +} + + +static void +loop_movables_free (movables) + struct loop_movables *movables; +{ + struct movable *m; + struct movable *m_next; + + for (m = movables->head; m; m = m_next) + { + m_next = m->next; + free (m); + } } #if 0 @@ -2242,9 +2295,9 @@ static void replace_call_address (x, reg, addr) rtx x, reg, addr; { - register enum rtx_code code; - register int i; - register char *fmt; + enum rtx_code code; + int i; + const char *fmt; if (x == 0) return; @@ -2278,7 +2331,7 @@ replace_call_address (x, reg, addr) abort (); XEXP (x, 0) = addr; return; - + default: break; } @@ -2288,9 +2341,9 @@ replace_call_address (x, reg, addr) { if (fmt[i] == 'e') replace_call_address (XEXP (x, i), reg, addr); - if (fmt[i] == 'E') + else if (fmt[i] == 'E') { - register int j; + int j; for (j = 0; j < XVECLEN (x, i); j++) replace_call_address (XVECEXP (x, i, j), reg, addr); } @@ -2302,12 +2355,13 @@ replace_call_address (x, reg, addr) in the rtx X. */ static int -count_nonfixed_reads (x) +count_nonfixed_reads (loop, x) + const struct loop *loop; rtx x; { - register enum rtx_code code; - register int i; - register char *fmt; + enum rtx_code code; + int i; + const char *fmt; int value; if (x == 0) @@ -2327,9 +2381,9 @@ count_nonfixed_reads (x) return 0; case MEM: - return ((invariant_p (XEXP (x, 0)) != 1) - + count_nonfixed_reads (XEXP (x, 0))); - + return ((loop_invariant_p (loop, XEXP (x, 0)) != 1) + + count_nonfixed_reads (loop, XEXP (x, 0))); + default: break; } @@ -2339,367 +2393,284 @@ count_nonfixed_reads (x) for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e') - value += count_nonfixed_reads (XEXP (x, i)); + value += count_nonfixed_reads (loop, XEXP (x, i)); if (fmt[i] == 'E') { - register int j; + int j; for (j = 0; j < XVECLEN (x, i); j++) - value += count_nonfixed_reads (XVECEXP (x, i, j)); + value += count_nonfixed_reads (loop, XVECEXP (x, i, j)); } } return value; } - -#if 0 -/* P is an instruction that sets a register to the result of a ZERO_EXTEND. - Replace it with an instruction to load just the low bytes - if the machine supports such an instruction, - and insert above LOOP_START an instruction to clear the register. */ +/* Scan a loop setting the elements `cont', `vtop', `loops_enclosed', + `has_call', `has_nonconst_call', `has_volatile', `has_tablejump', + `unknown_address_altered', `unknown_constant_address_altered', and + `num_mem_sets' in LOOP. Also, fill in the array `mems' and the + list `store_mems' in LOOP. */ static void -constant_high_bytes (p, loop_start) - rtx p, loop_start; +prescan_loop (loop) + struct loop *loop; { - register rtx new; - register int insn_code_number; - - /* Try to change (SET (REG ...) (ZERO_EXTEND (..:B ...))) - to (SET (STRICT_LOW_PART (SUBREG:B (REG...))) ...). */ - - new = gen_rtx_SET (VOIDmode, - gen_rtx_STRICT_LOW_PART (VOIDmode, - gen_rtx_SUBREG (GET_MODE (XEXP (SET_SRC (PATTERN (p)), 0)), - SET_DEST (PATTERN (p)), - 0)), - XEXP (SET_SRC (PATTERN (p)), 0)); - insn_code_number = recog (new, p); - - if (insn_code_number) - { - register int i; - - /* Clear destination register before the loop. */ - emit_insn_before (gen_rtx_SET (VOIDmode, SET_DEST (PATTERN (p)), - const0_rtx), - loop_start); - - /* Inside the loop, just load the low part. */ - PATTERN (p) = new; - } -} -#endif - -/* Scan a loop setting the variables `unknown_address_altered', - `num_mem_sets', `loop_continue', `loops_enclosed', `loop_has_call', - `loop_has_volatile', and `loop_has_tablejump'. - Also, fill in the array `loop_mems' and the list `loop_store_mems'. */ - -static void -prescan_loop (start, end) - rtx start, end; -{ - register int level = 1; + int level = 1; rtx insn; - int loop_has_multiple_exit_targets = 0; + struct loop_info *loop_info = LOOP_INFO (loop); + rtx start = loop->start; + rtx end = loop->end; /* The label after END. Jumping here is just like falling off the end of the loop. We use next_nonnote_insn instead of next_label as a hedge against the (pathological) case where some actual insn might end up between the two. */ rtx exit_target = next_nonnote_insn (end); - if (exit_target == NULL_RTX || GET_CODE (exit_target) != CODE_LABEL) - loop_has_multiple_exit_targets = 1; - unknown_address_altered = 0; - loop_has_call = 0; - loop_has_volatile = 0; - loop_has_tablejump = 0; - loop_store_mems = NULL_RTX; - first_loop_store_insn = NULL_RTX; - loop_mems_idx = 0; + loop_info->has_indirect_jump = indirect_jump_in_function; + loop_info->pre_header_has_call = 0; + loop_info->has_call = 0; + loop_info->has_nonconst_call = 0; + loop_info->has_volatile = 0; + loop_info->has_tablejump = 0; + loop_info->has_multiple_exit_targets = 0; + loop->level = 1; + + loop_info->unknown_address_altered = 0; + loop_info->unknown_constant_address_altered = 0; + loop_info->store_mems = NULL_RTX; + loop_info->first_loop_store_insn = NULL_RTX; + loop_info->mems_idx = 0; + loop_info->num_mem_sets = 0; - num_mem_sets = 0; - loops_enclosed = 1; - loop_continue = 0; + + for (insn = start; insn && GET_CODE (insn) != CODE_LABEL; + insn = PREV_INSN (insn)) + { + if (GET_CODE (insn) == CALL_INSN) + { + loop_info->pre_header_has_call = 1; + break; + } + } for (insn = NEXT_INSN (start); insn != NEXT_INSN (end); insn = NEXT_INSN (insn)) { - if (GET_CODE (insn) == NOTE) + switch (GET_CODE (insn)) { + case NOTE: if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG) { ++level; /* Count number of loops contained in this one. */ - loops_enclosed++; + loop->level++; } else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END) + --level; + break; + + case CALL_INSN: + if (! CONST_OR_PURE_CALL_P (insn)) { - --level; - if (level == 0) - { - end = insn; - break; - } + loop_info->unknown_address_altered = 1; + loop_info->has_nonconst_call = 1; } - else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT) + loop_info->has_call = 1; + if (can_throw_internal (insn)) + loop_info->has_multiple_exit_targets = 1; + break; + + case JUMP_INSN: + if (! loop_info->has_multiple_exit_targets) { - if (level == 1) - loop_continue = insn; + rtx set = pc_set (insn); + + if (set) + { + rtx label1, label2; + + if (GET_CODE (SET_SRC (set)) == IF_THEN_ELSE) + { + label1 = XEXP (SET_SRC (set), 1); + label2 = XEXP (SET_SRC (set), 2); + } + else + { + label1 = SET_SRC (PATTERN (insn)); + label2 = NULL_RTX; + } + + do + { + if (label1 && label1 != pc_rtx) + { + if (GET_CODE (label1) != LABEL_REF) + { + /* Something tricky. */ + loop_info->has_multiple_exit_targets = 1; + break; + } + else if (XEXP (label1, 0) != exit_target + && LABEL_OUTSIDE_LOOP_P (label1)) + { + /* A jump outside the current loop. */ + loop_info->has_multiple_exit_targets = 1; + break; + } + } + + label1 = label2; + label2 = NULL_RTX; + } + while (label1); + } + else + { + /* A return, or something tricky. */ + loop_info->has_multiple_exit_targets = 1; + } } - } - else if (GET_CODE (insn) == CALL_INSN) - { - if (! CONST_CALL_P (insn)) - unknown_address_altered = 1; - loop_has_call = 1; - } - else if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN) - { - rtx label1 = NULL_RTX; - rtx label2 = NULL_RTX; + /* FALLTHRU */ + case INSN: if (volatile_refs_p (PATTERN (insn))) - loop_has_volatile = 1; + loop_info->has_volatile = 1; if (GET_CODE (insn) == JUMP_INSN && (GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC || GET_CODE (PATTERN (insn)) == ADDR_VEC)) - loop_has_tablejump = 1; - - note_stores (PATTERN (insn), note_addr_stored); - if (! first_loop_store_insn && loop_store_mems) - first_loop_store_insn = insn; - - if (! loop_has_multiple_exit_targets - && GET_CODE (insn) == JUMP_INSN - && GET_CODE (PATTERN (insn)) == SET - && SET_DEST (PATTERN (insn)) == pc_rtx) - { - if (GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE) - { - label1 = XEXP (SET_SRC (PATTERN (insn)), 1); - label2 = XEXP (SET_SRC (PATTERN (insn)), 2); - } - else - { - label1 = SET_SRC (PATTERN (insn)); - } + loop_info->has_tablejump = 1; - do { - if (label1 && label1 != pc_rtx) - { - if (GET_CODE (label1) != LABEL_REF) - { - /* Something tricky. */ - loop_has_multiple_exit_targets = 1; - break; - } - else if (XEXP (label1, 0) != exit_target - && LABEL_OUTSIDE_LOOP_P (label1)) - { - /* A jump outside the current loop. */ - loop_has_multiple_exit_targets = 1; - break; - } - } + note_stores (PATTERN (insn), note_addr_stored, loop_info); + if (! loop_info->first_loop_store_insn && loop_info->store_mems) + loop_info->first_loop_store_insn = insn; - label1 = label2; - label2 = NULL_RTX; - } while (label1); - } + if (flag_non_call_exceptions && can_throw_internal (insn)) + loop_info->has_multiple_exit_targets = 1; + break; + + default: + break; } - else if (GET_CODE (insn) == RETURN) - loop_has_multiple_exit_targets = 1; } /* Now, rescan the loop, setting up the LOOP_MEMS array. */ - if (/* We can't tell what MEMs are aliased by what. */ - !unknown_address_altered - /* An exception thrown by a called function might land us + if (/* An exception thrown by a called function might land us anywhere. */ - && !loop_has_call + ! loop_info->has_nonconst_call /* We don't want loads for MEMs moved to a location before the one at which their stack memory becomes allocated. (Note that this is not a problem for malloc, etc., since those require actual function calls. */ - && !current_function_calls_alloca + && ! current_function_calls_alloca /* There are ways to leave the loop other than falling off the end. */ - && !loop_has_multiple_exit_targets) + && ! loop_info->has_multiple_exit_targets) for (insn = NEXT_INSN (start); insn != NEXT_INSN (end); insn = NEXT_INSN (insn)) - for_each_rtx (&insn, insert_loop_mem, 0); -} - -/* LOOP_NUMBER_CONT_DOMINATOR is now the last label between the loop start - and the continue note that is a the destination of a (cond)jump after - the continue note. If there is any (cond)jump between the loop start - and what we have so far as LOOP_NUMBER_CONT_DOMINATOR that has a - target between LOOP_DOMINATOR and the continue note, move - LOOP_NUMBER_CONT_DOMINATOR forward to that label; if a jump's - destination cannot be determined, clear LOOP_NUMBER_CONT_DOMINATOR. */ + for_each_rtx (&insn, insert_loop_mem, loop_info); -static void -verify_dominator (loop_number) - int loop_number; -{ - rtx insn; - - if (! loop_number_cont_dominator[loop_number]) - /* This can happen for an empty loop, e.g. in - gcc.c-torture/compile/920410-2.c */ - return; - if (loop_number_cont_dominator[loop_number] == const0_rtx) + /* BLKmode MEMs are added to LOOP_STORE_MEM as necessary so + that loop_invariant_p and load_mems can use true_dependence + to determine what is really clobbered. */ + if (loop_info->unknown_address_altered) { - loop_number_cont_dominator[loop_number] = 0; - return; + rtx mem = gen_rtx_MEM (BLKmode, const0_rtx); + + loop_info->store_mems + = gen_rtx_EXPR_LIST (VOIDmode, mem, loop_info->store_mems); } - for (insn = loop_number_loop_starts[loop_number]; - insn != loop_number_cont_dominator[loop_number]; - insn = NEXT_INSN (insn)) + if (loop_info->unknown_constant_address_altered) { - if (GET_CODE (insn) == JUMP_INSN - && GET_CODE (PATTERN (insn)) != RETURN) - { - rtx label = JUMP_LABEL (insn); - int label_luid; - - /* If it is not a jump we can easily understand or for - which we do not have jump target information in the JUMP_LABEL - field (consider ADDR_VEC and ADDR_DIFF_VEC insns), then clear - LOOP_NUMBER_CONT_DOMINATOR. */ - if ((! condjump_p (insn) - && ! condjump_in_parallel_p (insn)) - || label == NULL_RTX) - { - loop_number_cont_dominator[loop_number] = NULL_RTX; - return; - } + rtx mem = gen_rtx_MEM (BLKmode, const0_rtx); - label_luid = INSN_LUID (label); - if (label_luid < INSN_LUID (loop_number_loop_cont[loop_number]) - && (label_luid - > INSN_LUID (loop_number_cont_dominator[loop_number]))) - loop_number_cont_dominator[loop_number] = label; - } + RTX_UNCHANGING_P (mem) = 1; + loop_info->store_mems + = gen_rtx_EXPR_LIST (VOIDmode, mem, loop_info->store_mems); } } - + /* Scan the function looking for loops. Record the start and end of each loop. Also mark as invalid loops any loops that contain a setjmp or are branched to from outside the loop. */ static void -find_and_verify_loops (f) +find_and_verify_loops (f, loops) rtx f; + struct loops *loops; { - rtx insn, label; - int current_loop = -1; - int next_loop = -1; - int loop; + rtx insn; + rtx label; + int num_loops; + struct loop *current_loop; + struct loop *next_loop; + struct loop *loop; + + num_loops = loops->num; compute_luids (f, NULL_RTX, 0); /* If there are jumps to undefined labels, treat them as jumps out of any/all loops. This also avoids writing past end of tables when there are no loops. */ - uid_loop_num[0] = -1; + uid_loop[0] = NULL; /* Find boundaries of loops, mark which loops are contained within loops, and invalidate loops that have setjmp. */ + num_loops = 0; + current_loop = NULL; for (insn = f; insn; insn = NEXT_INSN (insn)) { if (GET_CODE (insn) == NOTE) switch (NOTE_LINE_NUMBER (insn)) { case NOTE_INSN_LOOP_BEG: - loop_number_loop_starts[++next_loop] = insn; - loop_number_loop_ends[next_loop] = 0; - loop_number_loop_cont[next_loop] = 0; - loop_number_cont_dominator[next_loop] = 0; - loop_outer_loop[next_loop] = current_loop; - loop_invalid[next_loop] = 0; - loop_number_exit_labels[next_loop] = 0; - loop_number_exit_count[next_loop] = 0; + next_loop = loops->array + num_loops; + next_loop->num = num_loops; + num_loops++; + next_loop->start = insn; + next_loop->outer = current_loop; current_loop = next_loop; break; - case NOTE_INSN_SETJMP: - /* In this case, we must invalidate our current loop and any - enclosing loop. */ - for (loop = current_loop; loop != -1; loop = loop_outer_loop[loop]) - { - loop_invalid[loop] = 1; - if (loop_dump_stream) - fprintf (loop_dump_stream, - "\nLoop at %d ignored due to setjmp.\n", - INSN_UID (loop_number_loop_starts[loop])); - } + case NOTE_INSN_LOOP_CONT: + current_loop->cont = insn; break; - case NOTE_INSN_LOOP_CONT: - loop_number_loop_cont[current_loop] = insn; + case NOTE_INSN_LOOP_VTOP: + current_loop->vtop = insn; break; + case NOTE_INSN_LOOP_END: - if (current_loop == -1) + if (! current_loop) abort (); - loop_number_loop_ends[current_loop] = insn; - verify_dominator (current_loop); - current_loop = loop_outer_loop[current_loop]; + current_loop->end = insn; + current_loop = current_loop->outer; break; default: break; } - /* If for any loop, this is a jump insn between the NOTE_INSN_LOOP_CONT - and NOTE_INSN_LOOP_END notes, update loop_number_loop_dominator. */ - else if (GET_CODE (insn) == JUMP_INSN - && GET_CODE (PATTERN (insn)) != RETURN - && current_loop >= 0) - { - int this_loop; - rtx label = JUMP_LABEL (insn); - - if (! condjump_p (insn) && ! condjump_in_parallel_p (insn)) - label = NULL_RTX; - this_loop = current_loop; - do + if (GET_CODE (insn) == CALL_INSN + && find_reg_note (insn, REG_SETJMP, NULL)) + { + /* In this case, we must invalidate our current loop and any + enclosing loop. */ + for (loop = current_loop; loop; loop = loop->outer) { - /* First see if we care about this loop. */ - if (loop_number_loop_cont[this_loop] - && loop_number_cont_dominator[this_loop] != const0_rtx) - { - /* If the jump destination is not known, invalidate - loop_number_const_dominator. */ - if (! label) - loop_number_cont_dominator[this_loop] = const0_rtx; - else - /* Check if the destination is between loop start and - cont. */ - if ((INSN_LUID (label) - < INSN_LUID (loop_number_loop_cont[this_loop])) - && (INSN_LUID (label) - > INSN_LUID (loop_number_loop_starts[this_loop])) - /* And if there is no later destination already - recorded. */ - && (! loop_number_cont_dominator[this_loop] - || (INSN_LUID (label) - > INSN_LUID (loop_number_cont_dominator - [this_loop])))) - loop_number_cont_dominator[this_loop] = label; - } - this_loop = loop_outer_loop[this_loop]; + loop->invalid = 1; + if (loop_dump_stream) + fprintf (loop_dump_stream, + "\nLoop at %d ignored due to setjmp.\n", + INSN_UID (loop->start)); } - while (this_loop >= 0); } /* Note that this will mark the NOTE_INSN_LOOP_END note as being in the enclosing loop, but this doesn't matter. */ - uid_loop_num[INSN_UID (insn)] = current_loop; + uid_loop[INSN_UID (insn)] = current_loop; } /* Any loop containing a label used in an initializer must be invalidated, @@ -2707,12 +2678,9 @@ find_and_verify_loops (f) for (label = forced_labels; label; label = XEXP (label, 1)) { - int loop_num; - - for (loop_num = uid_loop_num[INSN_UID (XEXP (label, 0))]; - loop_num != -1; - loop_num = loop_outer_loop[loop_num]) - loop_invalid[loop_num] = 1; + for (loop = uid_loop[INSN_UID (XEXP (label, 0))]; + loop; loop = loop->outer) + loop->invalid = 1; } /* Any loop containing a label used for an exception handler must be @@ -2720,12 +2688,9 @@ find_and_verify_loops (f) for (label = exception_handler_labels; label; label = XEXP (label, 1)) { - int loop_num; - - for (loop_num = uid_loop_num[INSN_UID (XEXP (label, 0))]; - loop_num != -1; - loop_num = loop_outer_loop[loop_num]) - loop_invalid[loop_num] = 1; + for (loop = uid_loop[INSN_UID (XEXP (label, 0))]; + loop; loop = loop->outer) + loop->invalid = 1; } /* Now scan all insn's in the function. If any JUMP_INSN branches into a @@ -2735,49 +2700,47 @@ find_and_verify_loops (f) anywhere. Also look for blocks of code ending in an unconditional branch that - exits the loop. If such a block is surrounded by a conditional + exits the loop. If such a block is surrounded by a conditional branch around the block, move the block elsewhere (see below) and invert the jump to point to the code block. This may eliminate a label in our loop and will simplify processing by both us and a possible second cse pass. */ for (insn = f; insn; insn = NEXT_INSN (insn)) - if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') + if (INSN_P (insn)) { - int this_loop_num = uid_loop_num[INSN_UID (insn)]; + struct loop *this_loop = uid_loop[INSN_UID (insn)]; if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) { rtx note = find_reg_note (insn, REG_LABEL, NULL_RTX); if (note) { - int loop_num; - - for (loop_num = uid_loop_num[INSN_UID (XEXP (note, 0))]; - loop_num != -1; - loop_num = loop_outer_loop[loop_num]) - loop_invalid[loop_num] = 1; + for (loop = uid_loop[INSN_UID (XEXP (note, 0))]; + loop; loop = loop->outer) + loop->invalid = 1; } } if (GET_CODE (insn) != JUMP_INSN) continue; - mark_loop_jump (PATTERN (insn), this_loop_num); + mark_loop_jump (PATTERN (insn), this_loop); /* See if this is an unconditional branch outside the loop. */ - if (this_loop_num != -1 + if (this_loop && (GET_CODE (PATTERN (insn)) == RETURN - || (simplejump_p (insn) - && (uid_loop_num[INSN_UID (JUMP_LABEL (insn))] - != this_loop_num))) + || (any_uncondjump_p (insn) + && onlyjump_p (insn) + && (uid_loop[INSN_UID (JUMP_LABEL (insn))] + != this_loop))) && get_max_uid () < max_uid_for_loop) { rtx p; rtx our_next = next_real_insn (insn); rtx last_insn_to_move = NEXT_INSN (insn); - int dest_loop; - int outer_loop = -1; + struct loop *dest_loop; + struct loop *outer_loop = NULL; /* Go backwards until we reach the start of the loop, a label, or a JUMP_INSN. */ @@ -2794,12 +2757,12 @@ find_and_verify_loops (f) if (JUMP_LABEL (insn)) { - dest_loop = uid_loop_num[INSN_UID (JUMP_LABEL (insn))]; - if (dest_loop != -1) + dest_loop = uid_loop[INSN_UID (JUMP_LABEL (insn))]; + if (dest_loop) { - for (outer_loop = dest_loop; outer_loop != -1; - outer_loop = loop_outer_loop[outer_loop]) - if (outer_loop == this_loop_num) + for (outer_loop = dest_loop; outer_loop; + outer_loop = outer_loop->outer) + if (outer_loop == this_loop) break; } } @@ -2807,8 +2770,8 @@ find_and_verify_loops (f) /* Make sure that the target of P is within the current loop. */ if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) - && uid_loop_num[INSN_UID (JUMP_LABEL (p))] != this_loop_num) - outer_loop = this_loop_num; + && uid_loop[INSN_UID (JUMP_LABEL (p))] != this_loop) + outer_loop = this_loop; /* If we stopped on a JUMP_INSN to the next insn after INSN, we have a block of code to try to move. @@ -2819,24 +2782,31 @@ find_and_verify_loops (f) of the block, invert the jump in P and point it to that label, and move the block of code to the spot we found. */ - if (outer_loop == -1 + if (! outer_loop && GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) != 0 /* Just ignore jumps to labels that were never emitted. These always indicate compilation errors. */ && INSN_UID (JUMP_LABEL (p)) != 0 - && condjump_p (p) - && ! simplejump_p (p) + && any_condjump_p (p) && onlyjump_p (p) && next_real_insn (JUMP_LABEL (p)) == our_next /* If it's not safe to move the sequence, then we mustn't try. */ - && insns_safe_to_move_p (p, NEXT_INSN (insn), + && insns_safe_to_move_p (p, NEXT_INSN (insn), &last_insn_to_move)) { rtx target = JUMP_LABEL (insn) ? JUMP_LABEL (insn) : get_last_insn (); - int target_loop_num = uid_loop_num[INSN_UID (target)]; + struct loop *target_loop = uid_loop[INSN_UID (target)]; rtx loc, loc2; + rtx tmp; + + /* Search for possible garbage past the conditional jumps + and look for the last barrier. */ + for (tmp = last_insn_to_move; + tmp && GET_CODE (tmp) != CODE_LABEL; tmp = NEXT_INSN (tmp)) + if (GET_CODE (tmp) == BARRIER) + last_insn_to_move = tmp; for (loc = target; loc; loc = PREV_INSN (loc)) if (GET_CODE (loc) == BARRIER @@ -2847,7 +2817,7 @@ find_and_verify_loops (f) || GET_CODE (loc2) != JUMP_INSN || (GET_CODE (PATTERN (loc2)) != ADDR_VEC && GET_CODE (PATTERN (loc2)) != ADDR_DIFF_VEC)) - && uid_loop_num[INSN_UID (loc)] == target_loop_num) + && uid_loop[INSN_UID (loc)] == target_loop) break; if (loc == 0) @@ -2860,7 +2830,7 @@ find_and_verify_loops (f) || GET_CODE (loc2) != JUMP_INSN || (GET_CODE (PATTERN (loc2)) != ADDR_VEC && GET_CODE (PATTERN (loc2)) != ADDR_DIFF_VEC)) - && uid_loop_num[INSN_UID (loc)] == target_loop_num) + && uid_loop[INSN_UID (loc)] == target_loop) break; if (loc) @@ -2871,91 +2841,88 @@ find_and_verify_loops (f) /* Ensure our label doesn't go away. */ LABEL_NUSES (cond_label)++; - /* Verify that uid_loop_num is large enough and that + /* Verify that uid_loop is large enough and that we can invert P. */ - if (invert_jump (p, new_label)) - { - rtx q, r; - - /* If no suitable BARRIER was found, create a suitable - one before TARGET. Since TARGET is a fall through - path, we'll need to insert an jump around our block - and a add a BARRIER before TARGET. - - This creates an extra unconditional jump outside - the loop. However, the benefits of removing rarely - executed instructions from inside the loop usually - outweighs the cost of the extra unconditional jump - outside the loop. */ - if (loc == 0) - { - rtx temp; - - temp = gen_jump (JUMP_LABEL (insn)); - temp = emit_jump_insn_before (temp, target); - JUMP_LABEL (temp) = JUMP_LABEL (insn); - LABEL_NUSES (JUMP_LABEL (insn))++; - loc = emit_barrier_before (target); - } - - /* Include the BARRIER after INSN and copy the - block after LOC. */ - new_label = squeeze_notes (new_label, - last_insn_to_move); - reorder_insns (new_label, last_insn_to_move, loc); - - /* All those insns are now in TARGET_LOOP_NUM. */ - for (q = new_label; - q != NEXT_INSN (last_insn_to_move); - q = NEXT_INSN (q)) - uid_loop_num[INSN_UID (q)] = target_loop_num; - - /* The label jumped to by INSN is no longer a loop exit. - Unless INSN does not have a label (e.g., it is a - RETURN insn), search loop_number_exit_labels to find - its label_ref, and remove it. Also turn off - LABEL_OUTSIDE_LOOP_P bit. */ - if (JUMP_LABEL (insn)) - { - int loop_num; - - for (q = 0, - r = loop_number_exit_labels[this_loop_num]; - r; q = r, r = LABEL_NEXTREF (r)) - if (XEXP (r, 0) == JUMP_LABEL (insn)) - { - LABEL_OUTSIDE_LOOP_P (r) = 0; - if (q) - LABEL_NEXTREF (q) = LABEL_NEXTREF (r); - else - loop_number_exit_labels[this_loop_num] - = LABEL_NEXTREF (r); - break; - } - - for (loop_num = this_loop_num; - loop_num != -1 && loop_num != target_loop_num; - loop_num = loop_outer_loop[loop_num]) - loop_number_exit_count[loop_num]--; - - /* If we didn't find it, then something is wrong. */ - if (! r) - abort (); - } - - /* P is now a jump outside the loop, so it must be put - in loop_number_exit_labels, and marked as such. - The easiest way to do this is to just call - mark_loop_jump again for P. */ - mark_loop_jump (PATTERN (p), this_loop_num); - - /* If INSN now jumps to the insn after it, - delete INSN. */ - if (JUMP_LABEL (insn) != 0 - && (next_real_insn (JUMP_LABEL (insn)) - == next_real_insn (insn))) - delete_insn (insn); - } + if (invert_jump (p, new_label, 1)) + { + rtx q, r; + + /* If no suitable BARRIER was found, create a suitable + one before TARGET. Since TARGET is a fall through + path, we'll need to insert an jump around our block + and add a BARRIER before TARGET. + + This creates an extra unconditional jump outside + the loop. However, the benefits of removing rarely + executed instructions from inside the loop usually + outweighs the cost of the extra unconditional jump + outside the loop. */ + if (loc == 0) + { + rtx temp; + + temp = gen_jump (JUMP_LABEL (insn)); + temp = emit_jump_insn_before (temp, target); + JUMP_LABEL (temp) = JUMP_LABEL (insn); + LABEL_NUSES (JUMP_LABEL (insn))++; + loc = emit_barrier_before (target); + } + + /* Include the BARRIER after INSN and copy the + block after LOC. */ + if (squeeze_notes (&new_label, &last_insn_to_move)) + abort (); + reorder_insns (new_label, last_insn_to_move, loc); + + /* All those insns are now in TARGET_LOOP. */ + for (q = new_label; + q != NEXT_INSN (last_insn_to_move); + q = NEXT_INSN (q)) + uid_loop[INSN_UID (q)] = target_loop; + + /* The label jumped to by INSN is no longer a loop + exit. Unless INSN does not have a label (e.g., + it is a RETURN insn), search loop->exit_labels + to find its label_ref, and remove it. Also turn + off LABEL_OUTSIDE_LOOP_P bit. */ + if (JUMP_LABEL (insn)) + { + for (q = 0, r = this_loop->exit_labels; + r; + q = r, r = LABEL_NEXTREF (r)) + if (XEXP (r, 0) == JUMP_LABEL (insn)) + { + LABEL_OUTSIDE_LOOP_P (r) = 0; + if (q) + LABEL_NEXTREF (q) = LABEL_NEXTREF (r); + else + this_loop->exit_labels = LABEL_NEXTREF (r); + break; + } + + for (loop = this_loop; loop && loop != target_loop; + loop = loop->outer) + loop->exit_count--; + + /* If we didn't find it, then something is + wrong. */ + if (! r) + abort (); + } + + /* P is now a jump outside the loop, so it must be put + in loop->exit_labels, and marked as such. + The easiest way to do this is to just call + mark_loop_jump again for P. */ + mark_loop_jump (PATTERN (p), this_loop); + + /* If INSN now jumps to the insn after it, + delete INSN. */ + if (JUMP_LABEL (insn) != 0 + && (next_real_insn (JUMP_LABEL (insn)) + == next_real_insn (insn))) + delete_related_insns (insn); + } /* Continue the loop after where the conditional branch used to jump, since the only branch insn @@ -2964,7 +2931,7 @@ find_and_verify_loops (f) insn = NEXT_INSN (cond_label); if (--LABEL_NUSES (cond_label) == 0) - delete_insn (cond_label); + delete_related_insns (cond_label); /* This loop will be continued with NEXT_INSN (insn). */ insn = PREV_INSN (insn); @@ -2980,12 +2947,12 @@ find_and_verify_loops (f) For speed, we assume that X is part of a pattern of a JUMP_INSN. */ static void -mark_loop_jump (x, loop_num) +mark_loop_jump (x, loop) rtx x; - int loop_num; + struct loop *loop; { - int dest_loop; - int outer_loop; + struct loop *dest_loop; + struct loop *outer_loop; int i; switch (GET_CODE (x)) @@ -3002,28 +2969,28 @@ mark_loop_jump (x, loop_num) case CONST: /* There could be a label reference in here. */ - mark_loop_jump (XEXP (x, 0), loop_num); + mark_loop_jump (XEXP (x, 0), loop); return; case PLUS: case MINUS: case MULT: - mark_loop_jump (XEXP (x, 0), loop_num); - mark_loop_jump (XEXP (x, 1), loop_num); + mark_loop_jump (XEXP (x, 0), loop); + mark_loop_jump (XEXP (x, 1), loop); return; case LO_SUM: /* This may refer to a LABEL_REF or SYMBOL_REF. */ - mark_loop_jump (XEXP (x, 1), loop_num); + mark_loop_jump (XEXP (x, 1), loop); return; case SIGN_EXTEND: case ZERO_EXTEND: - mark_loop_jump (XEXP (x, 0), loop_num); + mark_loop_jump (XEXP (x, 0), loop); return; case LABEL_REF: - dest_loop = uid_loop_num[INSN_UID (XEXP (x, 0))]; + dest_loop = uid_loop[INSN_UID (XEXP (x, 0))]; /* Link together all labels that branch outside the loop. This is used by final_[bg]iv_value and the loop unrolling code. Also @@ -3032,75 +2999,74 @@ mark_loop_jump (x, loop_num) /* A check to make sure the label is not in an inner nested loop, since this does not count as a loop exit. */ - if (dest_loop != -1) + if (dest_loop) { - for (outer_loop = dest_loop; outer_loop != -1; - outer_loop = loop_outer_loop[outer_loop]) - if (outer_loop == loop_num) + for (outer_loop = dest_loop; outer_loop; + outer_loop = outer_loop->outer) + if (outer_loop == loop) break; } else - outer_loop = -1; + outer_loop = NULL; - if (loop_num != -1 && outer_loop == -1) + if (loop && ! outer_loop) { LABEL_OUTSIDE_LOOP_P (x) = 1; - LABEL_NEXTREF (x) = loop_number_exit_labels[loop_num]; - loop_number_exit_labels[loop_num] = x; + LABEL_NEXTREF (x) = loop->exit_labels; + loop->exit_labels = x; - for (outer_loop = loop_num; - outer_loop != -1 && outer_loop != dest_loop; - outer_loop = loop_outer_loop[outer_loop]) - loop_number_exit_count[outer_loop]++; + for (outer_loop = loop; + outer_loop && outer_loop != dest_loop; + outer_loop = outer_loop->outer) + outer_loop->exit_count++; } /* If this is inside a loop, but not in the current loop or one enclosed by it, it invalidates at least one loop. */ - if (dest_loop == -1) + if (! dest_loop) return; /* We must invalidate every nested loop containing the target of this label, except those that also contain the jump insn. */ - for (; dest_loop != -1; dest_loop = loop_outer_loop[dest_loop]) + for (; dest_loop; dest_loop = dest_loop->outer) { /* Stop when we reach a loop that also contains the jump insn. */ - for (outer_loop = loop_num; outer_loop != -1; - outer_loop = loop_outer_loop[outer_loop]) + for (outer_loop = loop; outer_loop; outer_loop = outer_loop->outer) if (dest_loop == outer_loop) return; /* If we get here, we know we need to invalidate a loop. */ - if (loop_dump_stream && ! loop_invalid[dest_loop]) + if (loop_dump_stream && ! dest_loop->invalid) fprintf (loop_dump_stream, "\nLoop at %d ignored due to multiple entry points.\n", - INSN_UID (loop_number_loop_starts[dest_loop])); - - loop_invalid[dest_loop] = 1; + INSN_UID (dest_loop->start)); + + dest_loop->invalid = 1; } return; case SET: /* If this is not setting pc, ignore. */ if (SET_DEST (x) == pc_rtx) - mark_loop_jump (SET_SRC (x), loop_num); + mark_loop_jump (SET_SRC (x), loop); return; case IF_THEN_ELSE: - mark_loop_jump (XEXP (x, 1), loop_num); - mark_loop_jump (XEXP (x, 2), loop_num); + mark_loop_jump (XEXP (x, 1), loop); + mark_loop_jump (XEXP (x, 2), loop); return; case PARALLEL: case ADDR_VEC: for (i = 0; i < XVECLEN (x, 0); i++) - mark_loop_jump (XVECEXP (x, 0, i), loop_num); + mark_loop_jump (XVECEXP (x, 0, i), loop); return; case ADDR_DIFF_VEC: for (i = 0; i < XVECLEN (x, 1); i++) - mark_loop_jump (XVECEXP (x, 1, i), loop_num); + mark_loop_jump (XVECEXP (x, 1, i), loop); return; default: @@ -3108,16 +3074,15 @@ mark_loop_jump (x, loop_num) jump out of the loop. However, we have no way to link the destination of this jump onto the list of exit labels. To be safe we mark this loop and any containing loops as invalid. */ - if (loop_num != -1) + if (loop) { - for (outer_loop = loop_num; outer_loop != -1; - outer_loop = loop_outer_loop[outer_loop]) + for (outer_loop = loop; outer_loop; outer_loop = outer_loop->outer) { - if (loop_dump_stream && ! loop_invalid[outer_loop]) + if (loop_dump_stream && ! outer_loop->invalid) fprintf (loop_dump_stream, "\nLoop at %d ignored due to unknown exit jump.\n", - INSN_UID (loop_number_loop_starts[outer_loop])); - loop_invalid[outer_loop] = 1; + INSN_UID (outer_loop->start)); + outer_loop->invalid = 1; } } return; @@ -3147,37 +3112,48 @@ labels_in_range_p (insn, end) /* Record that a memory reference X is being set. */ static void -note_addr_stored (x, y) +note_addr_stored (x, y, data) rtx x; rtx y ATTRIBUTE_UNUSED; + void *data ATTRIBUTE_UNUSED; { + struct loop_info *loop_info = data; + if (x == 0 || GET_CODE (x) != MEM) return; /* Count number of memory writes. This affects heuristics in strength_reduce. */ - num_mem_sets++; + loop_info->num_mem_sets++; /* BLKmode MEM means all memory is clobbered. */ if (GET_MODE (x) == BLKmode) - unknown_address_altered = 1; + { + if (RTX_UNCHANGING_P (x)) + loop_info->unknown_constant_address_altered = 1; + else + loop_info->unknown_address_altered = 1; - if (unknown_address_altered) - return; + return; + } - loop_store_mems = gen_rtx_EXPR_LIST (VOIDmode, x, loop_store_mems); + loop_info->store_mems = gen_rtx_EXPR_LIST (VOIDmode, x, + loop_info->store_mems); } /* X is a value modified by an INSN that references a biv inside a loop exit test (ie, X is somehow related to the value of the biv). If X is a pseudo that is used more than once, then the biv is (effectively) - used more than once. */ + used more than once. DATA is a pointer to a loop_regs structure. */ static void -note_set_pseudo_multiple_uses (x, y) +note_set_pseudo_multiple_uses (x, y, data) rtx x; rtx y ATTRIBUTE_UNUSED; + void *data; { + struct loop_regs *regs = (struct loop_regs *) data; + if (x == 0) return; @@ -3193,26 +3169,28 @@ note_set_pseudo_multiple_uses (x, y) /* If we do not have usage information, or if we know the register is used more than once, note that fact for check_dbra_loop. */ if (REGNO (x) >= max_reg_before_loop - || ! VARRAY_RTX (reg_single_usage, REGNO (x)) - || VARRAY_RTX (reg_single_usage, REGNO (x)) == const0_rtx) - note_set_pseudo_multiple_uses_retval = 1; + || ! regs->array[REGNO (x)].single_usage + || regs->array[REGNO (x)].single_usage == const0_rtx) + regs->multiple_uses = 1; } /* Return nonzero if the rtx X is invariant over the current loop. The value is 2 if we refer to something only conditionally invariant. - If `unknown_address_altered' is nonzero, no memory ref is invariant. - Otherwise, a memory ref is invariant if it does not conflict with - anything stored in `loop_store_mems'. */ + A memory ref is invariant if it is not volatile and does not conflict + with anything stored in `loop_info->store_mems'. */ int -invariant_p (x) - register rtx x; +loop_invariant_p (loop, x) + const struct loop *loop; + rtx x; { - register int i; - register enum rtx_code code; - register char *fmt; + struct loop_info *loop_info = LOOP_INFO (loop); + struct loop_regs *regs = LOOP_REGS (loop); + int i; + enum rtx_code code; + const char *fmt; int conditional = 0; rtx mem_list_entry; @@ -3252,18 +3230,18 @@ invariant_p (x) since the reg might be set by initialization within the loop. */ if ((x == frame_pointer_rtx || x == hard_frame_pointer_rtx - || x == arg_pointer_rtx) + || x == arg_pointer_rtx || x == pic_offset_table_rtx) && ! current_function_has_nonlocal_goto) return 1; - if (loop_has_call + if (LOOP_INFO (loop)->has_call && REGNO (x) < FIRST_PSEUDO_REGISTER && call_used_regs[REGNO (x)]) return 0; - if (VARRAY_INT (set_in_loop, REGNO (x)) < 0) + if (regs->array[REGNO (x)].set_in_loop < 0) return 2; - return VARRAY_INT (set_in_loop, REGNO (x)) == 0; + return regs->array[REGNO (x)].set_in_loop == 0; case MEM: /* Volatile memory references must be rejected. Do this before @@ -3272,23 +3250,14 @@ invariant_p (x) if (MEM_VOLATILE_P (x)) return 0; - /* Read-only items (such as constants in a constant pool) are - invariant if their address is. */ - if (RTX_UNCHANGING_P (x)) - break; - - /* If we had a subroutine call, any location in memory could have been - clobbered. */ - if (unknown_address_altered) - return 0; - /* See if there is any dependence between a store and this load. */ - mem_list_entry = loop_store_mems; + mem_list_entry = loop_info->store_mems; while (mem_list_entry) { if (true_dependence (XEXP (mem_list_entry, 0), VOIDmode, x, rtx_varies_p)) return 0; + mem_list_entry = XEXP (mem_list_entry, 1); } @@ -3301,7 +3270,7 @@ invariant_p (x) if (MEM_VOLATILE_P (x)) return 0; break; - + default: break; } @@ -3311,7 +3280,7 @@ invariant_p (x) { if (fmt[i] == 'e') { - int tem = invariant_p (XEXP (x, i)); + int tem = loop_invariant_p (loop, XEXP (x, i)); if (tem == 0) return 0; if (tem == 2) @@ -3319,10 +3288,10 @@ invariant_p (x) } else if (fmt[i] == 'E') { - register int j; + int j; for (j = 0; j < XVECLEN (x, i); j++) { - int tem = invariant_p (XVECEXP (x, i, j)); + int tem = loop_invariant_p (loop, XVECEXP (x, i, j)); if (tem == 0) return 0; if (tem == 2) @@ -3334,7 +3303,6 @@ invariant_p (x) return 1 + conditional; } - /* Return nonzero if all the insns in the loop that set REG are INSN and the immediately following insns, @@ -3347,16 +3315,18 @@ invariant_p (x) and that its source is invariant. */ static int -consec_sets_invariant_p (reg, n_sets, insn) +consec_sets_invariant_p (loop, reg, n_sets, insn) + const struct loop *loop; int n_sets; rtx reg, insn; { - register rtx p = insn; - register int regno = REGNO (reg); + struct loop_regs *regs = LOOP_REGS (loop); + rtx p = insn; + unsigned int regno = REGNO (reg); rtx temp; /* Number of sets we have to insist on finding after INSN. */ int count = n_sets - 1; - int old = VARRAY_INT (set_in_loop, regno); + int old = regs->array[regno].set_in_loop; int value = 0; int this; @@ -3364,11 +3334,11 @@ consec_sets_invariant_p (reg, n_sets, insn) if (n_sets == 127) return 0; - VARRAY_INT (set_in_loop, regno) = 0; + regs->array[regno].set_in_loop = 0; while (count > 0) { - register enum rtx_code code; + enum rtx_code code; rtx set; p = NEXT_INSN (p); @@ -3384,7 +3354,7 @@ consec_sets_invariant_p (reg, n_sets, insn) && GET_CODE (SET_DEST (set)) == REG && REGNO (SET_DEST (set)) == regno) { - this = invariant_p (SET_SRC (set)); + this = loop_invariant_p (loop, SET_SRC (set)); if (this != 0) value |= this; else if ((temp = find_reg_note (p, REG_EQUAL, NULL_RTX))) @@ -3394,7 +3364,7 @@ consec_sets_invariant_p (reg, n_sets, insn) notes are OK. */ this = (CONSTANT_P (XEXP (temp, 0)) || (find_reg_note (p, REG_RETVAL, NULL_RTX) - && invariant_p (XEXP (temp, 0)))); + && loop_invariant_p (loop, XEXP (temp, 0)))); if (this != 0) value |= this; } @@ -3403,13 +3373,13 @@ consec_sets_invariant_p (reg, n_sets, insn) count--; else if (code != NOTE) { - VARRAY_INT (set_in_loop, regno) = old; + regs->array[regno].set_in_loop = old; return 0; } } - VARRAY_INT (set_in_loop, regno) = old; - /* If invariant_p ever returned 2, we return 2. */ + regs->array[regno].set_in_loop = old; + /* If loop_invariant_p ever returned 2, we return 2. */ return 1 + (value & 2); } @@ -3425,12 +3395,12 @@ all_sets_invariant_p (reg, insn, table) rtx reg, insn; short *table; { - register rtx p = insn; - register int regno = REGNO (reg); + rtx p = insn; + int regno = REGNO (reg); while (1) { - register enum rtx_code code; + enum rtx_code code; p = NEXT_INSN (p); code = GET_CODE (p); if (code == CODE_LABEL || code == JUMP_INSN) @@ -3439,7 +3409,7 @@ all_sets_invariant_p (reg, insn, table) && GET_CODE (SET_DEST (PATTERN (p))) == REG && REGNO (SET_DEST (PATTERN (p))) == regno) { - if (!invariant_p (SET_SRC (PATTERN (p)), table)) + if (! loop_invariant_p (loop, SET_SRC (PATTERN (p)), table)) return 0; } } @@ -3451,55 +3421,56 @@ all_sets_invariant_p (reg, insn, table) a different insn, set USAGE[REGNO] to const0_rtx. */ static void -find_single_use_in_loop (insn, x, usage) +find_single_use_in_loop (regs, insn, x) + struct loop_regs *regs; rtx insn; rtx x; - varray_type usage; { enum rtx_code code = GET_CODE (x); - char *fmt = GET_RTX_FORMAT (code); + const char *fmt = GET_RTX_FORMAT (code); int i, j; if (code == REG) - VARRAY_RTX (usage, REGNO (x)) - = (VARRAY_RTX (usage, REGNO (x)) != 0 - && VARRAY_RTX (usage, REGNO (x)) != insn) + regs->array[REGNO (x)].single_usage + = (regs->array[REGNO (x)].single_usage != 0 + && regs->array[REGNO (x)].single_usage != insn) ? const0_rtx : insn; else if (code == SET) { /* Don't count SET_DEST if it is a REG; otherwise count things in SET_DEST because if a register is partially modified, it won't - show up as a potential movable so we don't care how USAGE is set + show up as a potential movable so we don't care how USAGE is set for it. */ if (GET_CODE (SET_DEST (x)) != REG) - find_single_use_in_loop (insn, SET_DEST (x), usage); - find_single_use_in_loop (insn, SET_SRC (x), usage); + find_single_use_in_loop (regs, insn, SET_DEST (x)); + find_single_use_in_loop (regs, insn, SET_SRC (x)); } else for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) { if (fmt[i] == 'e' && XEXP (x, i) != 0) - find_single_use_in_loop (insn, XEXP (x, i), usage); + find_single_use_in_loop (regs, insn, XEXP (x, i)); else if (fmt[i] == 'E') for (j = XVECLEN (x, i) - 1; j >= 0; j--) - find_single_use_in_loop (insn, XVECEXP (x, i, j), usage); + find_single_use_in_loop (regs, insn, XVECEXP (x, i, j)); } } /* Count and record any set in X which is contained in INSN. Update - MAY_NOT_MOVE and LAST_SET for any register set in X. */ + REGS->array[I].MAY_NOT_OPTIMIZE and LAST_SET for any register I set + in X. */ static void -count_one_set (insn, x, may_not_move, last_set) +count_one_set (regs, insn, x, last_set) + struct loop_regs *regs; rtx insn, x; - varray_type may_not_move; rtx *last_set; { if (GET_CODE (x) == CLOBBER && GET_CODE (XEXP (x, 0)) == REG) /* Don't move a reg that has an explicit clobber. It's not worth the pain to try to do it correctly. */ - VARRAY_CHAR (may_not_move, REGNO (XEXP (x, 0))) = 1; + regs->array[REGNO (XEXP (x, 0))].may_not_optimize = 1; if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER) { @@ -3511,154 +3482,605 @@ count_one_set (insn, x, may_not_move, last_set) dest = XEXP (dest, 0); if (GET_CODE (dest) == REG) { - register int regno = REGNO (dest); - /* If this is the first setting of this reg - in current basic block, and it was set before, - it must be set in two basic blocks, so it cannot - be moved out of the loop. */ - if (VARRAY_INT (set_in_loop, regno) > 0 - && last_set[regno] == 0) - VARRAY_CHAR (may_not_move, regno) = 1; - /* If this is not first setting in current basic block, - see if reg was used in between previous one and this. - If so, neither one can be moved. */ - if (last_set[regno] != 0 - && reg_used_between_p (dest, last_set[regno], insn)) - VARRAY_CHAR (may_not_move, regno) = 1; - if (VARRAY_INT (set_in_loop, regno) < 127) - ++VARRAY_INT (set_in_loop, regno); - last_set[regno] = insn; + int i; + int regno = REGNO (dest); + for (i = 0; i < LOOP_REGNO_NREGS (regno, dest); i++) + { + /* If this is the first setting of this reg + in current basic block, and it was set before, + it must be set in two basic blocks, so it cannot + be moved out of the loop. */ + if (regs->array[regno].set_in_loop > 0 + && last_set == 0) + regs->array[regno+i].may_not_optimize = 1; + /* If this is not first setting in current basic block, + see if reg was used in between previous one and this. + If so, neither one can be moved. */ + if (last_set[regno] != 0 + && reg_used_between_p (dest, last_set[regno], insn)) + regs->array[regno+i].may_not_optimize = 1; + if (regs->array[regno+i].set_in_loop < 127) + ++regs->array[regno+i].set_in_loop; + last_set[regno+i] = insn; + } } } } + +/* Given a loop that is bounded by LOOP->START and LOOP->END and that + is entered at LOOP->SCAN_START, return 1 if the register set in SET + contained in insn INSN is used by any insn that precedes INSN in + cyclic order starting from the loop entry point. -/* Increment SET_IN_LOOP at the index of each register - that is modified by an insn between FROM and TO. - If the value of an element of SET_IN_LOOP becomes 127 or more, - stop incrementing it, to avoid overflow. + We don't want to use INSN_LUID here because if we restrict INSN to those + that have a valid INSN_LUID, it means we cannot move an invariant out + from an inner loop past two loops. */ - Store in SINGLE_USAGE[I] the single insn in which register I is - used, if it is only used once. Otherwise, it is set to 0 (for no - uses) or const0_rtx for more than one use. This parameter may be zero, - in which case this processing is not done. +static int +loop_reg_used_before_p (loop, set, insn) + const struct loop *loop; + rtx set, insn; +{ + rtx reg = SET_DEST (set); + rtx p; + + /* Scan forward checking for register usage. If we hit INSN, we + are done. Otherwise, if we hit LOOP->END, wrap around to LOOP->START. */ + for (p = loop->scan_start; p != insn; p = NEXT_INSN (p)) + { + if (INSN_P (p) && reg_overlap_mentioned_p (reg, PATTERN (p))) + return 1; + + if (p == loop->end) + p = loop->start; + } + + return 0; +} + + +/* Information we collect about arrays that we might want to prefetch. */ +struct prefetch_info +{ + struct iv_class *class; /* Class this prefetch is based on. */ + struct induction *giv; /* GIV this prefetch is based on. */ + rtx base_address; /* Start prefetching from this address plus + index. */ + HOST_WIDE_INT index; + HOST_WIDE_INT stride; /* Prefetch stride in bytes in each + iteration. */ + unsigned int bytes_accesed; /* Sum of sizes of all acceses to this + prefetch area in one iteration. */ + unsigned int total_bytes; /* Total bytes loop will access in this block. + This is set only for loops with known + iteration counts and is 0xffffffff + otherwise. */ + unsigned int write : 1; /* 1 for read/write prefetches. */ + unsigned int prefetch_in_loop : 1; + /* 1 for those chosen for prefetching. */ + unsigned int prefetch_before_loop : 1; + /* 1 for those chosen for prefetching. */ +}; - Store in *COUNT_PTR the number of actual instruction - in the loop. We use this to decide what is worth moving out. */ +/* Data used by check_store function. */ +struct check_store_data +{ + rtx mem_address; + int mem_write; +}; -/* last_set[n] is nonzero iff reg n has been set in the current basic block. - In that case, it is the insn that last set reg n. */ +static void check_store PARAMS ((rtx, rtx, void *)); +static void emit_prefetch_instructions PARAMS ((struct loop *)); +static int rtx_equal_for_prefetch_p PARAMS ((rtx, rtx)); +/* Set mem_write when mem_address is found. Used as callback to + note_stores. */ static void -count_loop_regs_set (from, to, may_not_move, single_usage, count_ptr, nregs) - register rtx from, to; - varray_type may_not_move; - varray_type single_usage; - int *count_ptr; - int nregs; +check_store (x, pat, data) + rtx x, pat ATTRIBUTE_UNUSED; + void *data; { - register rtx *last_set = (rtx *) alloca (nregs * sizeof (rtx)); - register rtx insn; - register int count = 0; + struct check_store_data *d = (struct check_store_data *) data; + + if ((GET_CODE (x) == MEM) && rtx_equal_p (d->mem_address, XEXP (x, 0))) + d->mem_write = 1; +} + +/* Like rtx_equal_p, but attempts to swap commutative operands. This is + important to get some addresses combined. Later more sophisticated + transformations can be added when necesary. + + ??? Same trick with swapping operand is done at several other places. + It can be nice to develop some common way to handle this. */ + +static int +rtx_equal_for_prefetch_p (x, y) + rtx x, y; +{ + int i; + int j; + enum rtx_code code = GET_CODE (x); + const char *fmt; + + if (x == y) + return 1; + if (code != GET_CODE (y)) + return 0; + + code = GET_CODE (x); - bzero ((char *) last_set, nregs * sizeof (rtx)); - for (insn = from; insn != to; insn = NEXT_INSN (insn)) + if (GET_RTX_CLASS (code) == 'c') { - if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') + return ((rtx_equal_for_prefetch_p (XEXP (x, 0), XEXP (y, 0)) + && rtx_equal_for_prefetch_p (XEXP (x, 1), XEXP (y, 1))) + || (rtx_equal_for_prefetch_p (XEXP (x, 0), XEXP (y, 1)) + && rtx_equal_for_prefetch_p (XEXP (x, 1), XEXP (y, 0)))); + } + /* Compare the elements. If any pair of corresponding elements fails to + match, return 0 for the whole thing. */ + + fmt = GET_RTX_FORMAT (code); + for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) + { + switch (fmt[i]) { - ++count; + case 'w': + if (XWINT (x, i) != XWINT (y, i)) + return 0; + break; - /* Record registers that have exactly one use. */ - find_single_use_in_loop (insn, PATTERN (insn), single_usage); + case 'i': + if (XINT (x, i) != XINT (y, i)) + return 0; + break; - /* Include uses in REG_EQUAL notes. */ - if (REG_NOTES (insn)) - find_single_use_in_loop (insn, REG_NOTES (insn), single_usage); + case 'E': + /* Two vectors must have the same length. */ + if (XVECLEN (x, i) != XVECLEN (y, i)) + return 0; - if (GET_CODE (PATTERN (insn)) == SET - || GET_CODE (PATTERN (insn)) == CLOBBER) - count_one_set (insn, PATTERN (insn), may_not_move, last_set); - else if (GET_CODE (PATTERN (insn)) == PARALLEL) - { - register int i; - for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) - count_one_set (insn, XVECEXP (PATTERN (insn), 0, i), - may_not_move, last_set); - } - } + /* And the corresponding elements must match. */ + for (j = 0; j < XVECLEN (x, i); j++) + if (rtx_equal_for_prefetch_p (XVECEXP (x, i, j), + XVECEXP (y, i, j)) == 0) + return 0; + break; - if (GET_CODE (insn) == CODE_LABEL || GET_CODE (insn) == JUMP_INSN) - bzero ((char *) last_set, nregs * sizeof (rtx)); + case 'e': + if (rtx_equal_for_prefetch_p (XEXP (x, i), XEXP (y, i)) == 0) + return 0; + break; + + case 's': + if (strcmp (XSTR (x, i), XSTR (y, i))) + return 0; + break; + + case 'u': + /* These are just backpointers, so they don't matter. */ + break; + + case '0': + break; + + /* It is believed that rtx's at this level will never + contain anything but integers and other rtx's, + except for within LABEL_REFs and SYMBOL_REFs. */ + default: + abort (); + } } - *count_ptr = count; + return 1; } -/* Given a loop that is bounded by LOOP_START and LOOP_END - and that is entered at SCAN_START, - return 1 if the register set in SET contained in insn INSN is used by - any insn that precedes INSN in cyclic order starting - from the loop entry point. +/* Remove constant addition value from the expression X (when present) + and return it. */ - We don't want to use INSN_LUID here because if we restrict INSN to those - that have a valid INSN_LUID, it means we cannot move an invariant out - from an inner loop past two loops. */ - -static int -loop_reg_used_before_p (set, insn, loop_start, scan_start, loop_end) - rtx set, insn, loop_start, scan_start, loop_end; +static HOST_WIDE_INT +remove_constant_addition (x) + rtx *x; { - rtx reg = SET_DEST (set); - rtx p; + HOST_WIDE_INT addval = 0; + rtx exp = *x; - /* Scan forward checking for register usage. If we hit INSN, we - are done. Otherwise, if we hit LOOP_END, wrap around to LOOP_START. */ - for (p = scan_start; p != insn; p = NEXT_INSN (p)) + if (GET_CODE (exp) == CONST) + exp = XEXP (exp, 0); + if (GET_CODE (exp) == CONST_INT) { - if (GET_RTX_CLASS (GET_CODE (p)) == 'i' - && reg_overlap_mentioned_p (reg, PATTERN (p))) - return 1; + addval = INTVAL (exp); + *x = const0_rtx; + } + + /* For plus expression recurse on ourself. */ + else if (GET_CODE (exp) == PLUS) + { + addval += remove_constant_addition (&XEXP (exp, 0)); + addval += remove_constant_addition (&XEXP (exp, 1)); - if (p == loop_end) - p = loop_start; + /* In case our parameter was constant, remove extra zero from the + expression. */ + if (XEXP (exp, 0) == const0_rtx) + *x = XEXP (exp, 1); + else if (XEXP (exp, 1) == const0_rtx) + *x = XEXP (exp, 0); } - return 0; + return addval; } - -/* A "basic induction variable" or biv is a pseudo reg that is set - (within this loop) only by incrementing or decrementing it. */ -/* A "general induction variable" or giv is a pseudo reg whose - value is a linear function of a biv. */ -/* Bivs are recognized by `basic_induction_var'; - Givs by `general_induction_var'. */ +/* Attempt to identify accesses to arrays that are most likely to cause cache + misses, and emit prefetch instructions a few prefetch blocks forward. -/* Indexed by register number, indicates whether or not register is an - induction variable, and if so what type. */ + To detect the arrays we use the GIV information that was collected by the + strength reduction pass. -varray_type reg_iv_type; + The prefetch instructions are generated after the GIV information is done + and before the strength reduction process. The new GIVs are injected into + the strength reduction tables, so the prefetch addresses are optimized as + well. -/* Indexed by register number, contains pointer to `struct induction' - if register is an induction variable. This holds general info for - all induction variables. */ + GIVs are split into base address, stride, and constant addition values. + GIVs with the same address, stride and close addition values are combined + into a single prefetch. Also writes to GIVs are detected, so that prefetch + for write instructions can be used for the block we write to, on machines + that support write prefetches. -varray_type reg_iv_info; + Several heuristics are used to determine when to prefetch. They are + controlled by defined symbols that can be overridden for each target. */ -/* Indexed by register number, contains pointer to `struct iv_class' - if register is a basic induction variable. This holds info describing - the class (a related group) of induction variables that the biv belongs - to. */ +static void +emit_prefetch_instructions (loop) + struct loop *loop; +{ + int num_prefetches = 0; + int num_real_prefetches = 0; + int num_real_write_prefetches = 0; + int ahead; + int i; + struct iv_class *bl; + struct induction *iv; + struct prefetch_info info[MAX_PREFETCHES]; + struct loop_ivs *ivs = LOOP_IVS (loop); -struct iv_class **reg_biv_class; + if (!HAVE_prefetch) + return; -/* The head of a list which links together (via the next field) - every iv class for the current loop. */ + /* Consider only loops w/o calls. When a call is done, the loop is probably + slow enough to read the memory. */ + if (PREFETCH_NO_CALL && LOOP_INFO (loop)->has_call) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, "Prefetch: ignoring loop - has call.\n"); -struct iv_class *loop_iv_list; + return; + } -/* Givs made from biv increments are always splittable for loop unrolling. - Since there is no regscan info for them, we have to keep track of them - separately. */ -int first_increment_giv, last_increment_giv; + if (PREFETCH_NO_LOW_LOOPCNT + && LOOP_INFO (loop)->n_iterations + && LOOP_INFO (loop)->n_iterations <= PREFETCH_LOW_LOOPCNT) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, + "Prefetch: ignoring loop - not enought iterations.\n"); + return; + } + + /* Search all induction variables and pick those interesting for the prefetch + machinery. */ + for (bl = ivs->list; bl; bl = bl->next) + { + struct induction *biv = bl->biv, *biv1; + int basestride = 0; + + biv1 = biv; + + /* Expect all BIVs to be executed in each iteration. This makes our + analysis more conservative. */ + while (biv1) + { + /* Discard non-constant additions that we can't handle well yet, and + BIVs that are executed multiple times; such BIVs ought to be + handled in the nested loop. We accept not_every_iteration BIVs, + since these only result in larger strides and make our + heuristics more conservative. + ??? What does the last sentence mean? */ + if (GET_CODE (biv->add_val) != CONST_INT) + { + if (loop_dump_stream) + { + fprintf (loop_dump_stream, + "Prefetch: biv %i ignored: non-constant addition at insn %i:", + REGNO (biv->src_reg), INSN_UID (biv->insn)); + print_rtl (loop_dump_stream, biv->add_val); + fprintf (loop_dump_stream, "\n"); + } + break; + } + + if (biv->maybe_multiple) + { + if (loop_dump_stream) + { + fprintf (loop_dump_stream, + "Prefetch: biv %i ignored: maybe_multiple at insn %i:", + REGNO (biv->src_reg), INSN_UID (biv->insn)); + print_rtl (loop_dump_stream, biv->add_val); + fprintf (loop_dump_stream, "\n"); + } + break; + } + + basestride += INTVAL (biv1->add_val); + biv1 = biv1->next_iv; + } + + if (biv1 || !basestride) + continue; + + for (iv = bl->giv; iv; iv = iv->next_iv) + { + rtx address; + rtx temp; + HOST_WIDE_INT index = 0; + int add = 1; + HOST_WIDE_INT stride; + struct check_store_data d; + int size = GET_MODE_SIZE (GET_MODE (iv)); + + /* There are several reasons why an induction variable is not + interesting to us. */ + if (iv->giv_type != DEST_ADDR + /* We are interested only in constant stride memory references + in order to be able to compute density easily. */ + || GET_CODE (iv->mult_val) != CONST_INT + /* Don't handle reversed order prefetches, since they are usually + ineffective. Later we may be able to reverse such BIVs. */ + || (PREFETCH_NO_REVERSE_ORDER + && (stride = INTVAL (iv->mult_val) * basestride) < 0) + /* Prefetching of accesses with such an extreme stride is probably + not worthwhile, either. */ + || (PREFETCH_NO_EXTREME_STRIDE + && stride > PREFETCH_EXTREME_STRIDE) + /* Ignore GIVs with varying add values; we can't predict the + value for the next iteration. */ + || !loop_invariant_p (loop, iv->add_val) + /* Ignore GIVs in the nested loops; they ought to have been + handled already. */ + || iv->maybe_multiple) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, "Prefetch: Ignoring giv at %i\n", + INSN_UID (iv->insn)); + continue; + } + + /* Determine the pointer to the basic array we are examining. It is + the sum of the BIV's initial value and the GIV's add_val. */ + index = 0; + + address = copy_rtx (iv->add_val); + temp = copy_rtx (bl->initial_value); + + address = simplify_gen_binary (PLUS, Pmode, temp, address); + index = remove_constant_addition (&address); + + index += size; + d.mem_write = 0; + d.mem_address = *iv->location; + + /* When the GIV is not always executed, we might be better off by + not dirtying the cache pages. */ + if (PREFETCH_NOT_ALWAYS || iv->always_executed) + note_stores (PATTERN (iv->insn), check_store, &d); + + /* Attempt to find another prefetch to the same array and see if we + can merge this one. */ + for (i = 0; i < num_prefetches; i++) + if (rtx_equal_for_prefetch_p (address, info[i].base_address) + && stride == info[i].stride) + { + /* In case both access same array (same location + just with small difference in constant indexes), merge + the prefetches. Just do the later and the earlier will + get prefetched from previous iteration. + 4096 is artificial threshold. It should not be too small, + but also not bigger than small portion of memory usually + traversed by single loop. */ + if (index >= info[i].index && index - info[i].index < 4096) + { + info[i].write |= d.mem_write; + info[i].bytes_accesed += size; + info[i].index = index; + info[i].giv = iv; + info[i].class = bl; + info[num_prefetches].base_address = address; + add = 0; + break; + } + + if (index < info[i].index && info[i].index - index < 4096) + { + info[i].write |= d.mem_write; + info[i].bytes_accesed += size; + add = 0; + break; + } + } + + /* Merging failed. */ + if (add) + { + info[num_prefetches].giv = iv; + info[num_prefetches].class = bl; + info[num_prefetches].index = index; + info[num_prefetches].stride = stride; + info[num_prefetches].base_address = address; + info[num_prefetches].write = d.mem_write; + info[num_prefetches].bytes_accesed = size; + num_prefetches++; + if (num_prefetches >= MAX_PREFETCHES) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, + "Maximal number of prefetches exceeded.\n"); + return; + } + } + } + } + + for (i = 0; i < num_prefetches; i++) + { + /* Attempt to calculate the number of bytes fetched by the loop. + Avoid overflow. */ + if (LOOP_INFO (loop)->n_iterations + && ((unsigned HOST_WIDE_INT) (0xffffffff / info[i].stride) + >= LOOP_INFO (loop)->n_iterations)) + info[i].total_bytes = info[i].stride * LOOP_INFO (loop)->n_iterations; + else + info[i].total_bytes = 0xffffffff; + + /* Prefetch is worthwhile only when the loads/stores are dense. */ + if (PREFETCH_ONLY_DENSE_MEM + && info[i].bytes_accesed * 256 / info[i].stride > PREFETCH_DENSE_MEM + && (info[i].total_bytes / PREFETCH_BLOCK + >= PREFETCH_BLOCKS_BEFORE_LOOP_MIN)) + { + info[i].prefetch_before_loop = 1; + info[i].prefetch_in_loop + = (info[i].total_bytes / PREFETCH_BLOCK + > PREFETCH_BLOCKS_BEFORE_LOOP_MAX); + } + else + info[i].prefetch_in_loop = 0, info[i].prefetch_before_loop = 0; + + if (info[i].prefetch_in_loop) + { + num_real_prefetches += ((info[i].stride + PREFETCH_BLOCK - 1) + / PREFETCH_BLOCK); + if (info[i].write) + num_real_write_prefetches + += (info[i].stride + PREFETCH_BLOCK - 1) / PREFETCH_BLOCK; + } + } + + if (loop_dump_stream) + { + for (i = 0; i < num_prefetches; i++) + { + fprintf (loop_dump_stream, "Prefetch insn %i address: ", + INSN_UID (info[i].giv->insn)); + print_rtl (loop_dump_stream, info[i].base_address); + fprintf (loop_dump_stream, " Index: "); + fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, info[i].index); + fprintf (loop_dump_stream, " stride: "); + fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, info[i].stride); + fprintf (loop_dump_stream, + " density: %i%% total_bytes: %u%sin loop: %s before: %s\n", + (int) (info[i].bytes_accesed * 100 / info[i].stride), + info[i].total_bytes, + info[i].write ? " read/write " : " read only ", + info[i].prefetch_in_loop ? "yes" : "no", + info[i].prefetch_before_loop ? "yes" : "no"); + } + + fprintf (loop_dump_stream, "Real prefetches needed: %i (write: %i)\n", + num_real_prefetches, num_real_write_prefetches); + } + + if (!num_real_prefetches) + return; + + ahead = SIMULTANEOUS_PREFETCHES / num_real_prefetches; + + if (!ahead) + return; + + for (i = 0; i < num_prefetches; i++) + { + if (info[i].prefetch_in_loop) + { + int y; + + for (y = 0; y < ((info[i].stride + PREFETCH_BLOCK - 1) + / PREFETCH_BLOCK); y++) + { + rtx loc = copy_rtx (*info[i].giv->location); + rtx insn; + int bytes_ahead = PREFETCH_BLOCK * (ahead + y); + rtx before_insn = info[i].giv->insn; + rtx prev_insn = PREV_INSN (info[i].giv->insn); + + /* We can save some effort by offsetting the address on + architectures with offsettable memory references. */ + if (offsettable_address_p (0, VOIDmode, loc)) + loc = plus_constant (loc, bytes_ahead); + else + { + rtx reg = gen_reg_rtx (Pmode); + loop_iv_add_mult_emit_before (loop, loc, const1_rtx, + GEN_INT (bytes_ahead), reg, + 0, before_insn); + loc = reg; + } + + /* Make sure the address operand is valid for prefetch. */ + if (! (*insn_data[(int)CODE_FOR_prefetch].operand[0].predicate) + (loc, + insn_data[(int)CODE_FOR_prefetch].operand[0].mode)) + loc = force_reg (Pmode, loc); + emit_insn_before (gen_prefetch (loc, GEN_INT (info[i].write), + GEN_INT (3)), + before_insn); + + /* Check all insns emitted and record the new GIV + information. */ + insn = NEXT_INSN (prev_insn); + while (insn != before_insn) + { + insn = check_insn_for_givs (loop, insn, + info[i].giv->always_executed, + info[i].giv->maybe_multiple); + insn = NEXT_INSN (insn); + } + } + } + + if (info[i].prefetch_before_loop) + { + int y; + + /* Emit INSNs before the loop to fetch the first cache lines. */ + for (y = 0; + (!info[i].prefetch_in_loop || y < ahead) + && y * PREFETCH_BLOCK < (int) info[i].total_bytes; y ++) + { + rtx reg = gen_reg_rtx (Pmode); + rtx loop_start = loop->start; + rtx add_val = simplify_gen_binary (PLUS, Pmode, + info[i].giv->add_val, + GEN_INT (y * PREFETCH_BLOCK)); + + loop_iv_add_mult_emit_before (loop, info[i].class->initial_value, + info[i].giv->mult_val, + add_val, reg, 0, loop_start); + emit_insn_before (gen_prefetch (reg, GEN_INT (info[i].write), + GEN_INT (3)), + loop_start); + } + } + } + + return; +} + +/* A "basic induction variable" or biv is a pseudo reg that is set + (within this loop) only by incrementing or decrementing it. */ +/* A "general induction variable" or giv is a pseudo reg whose + value is a linear function of a biv. */ + +/* Bivs are recognized by `basic_induction_var'; + Givs by `general_induction_var'. */ /* Communication with routines called via `note_stores'. */ @@ -3695,132 +4117,47 @@ static rtx addr_placeholder; was rerun in loop_optimize whenever a register was added or moved. Also, some of the optimizations could be a little less conservative. */ -/* Perform strength reduction and induction variable elimination. - - Pseudo registers created during this function will be beyond the last - valid index in several tables including n_times_set and regno_last_uid. - This does not cause a problem here, because the added registers cannot be - givs outside of their loop, and hence will never be reconsidered. - But scan_loop must check regnos to make sure they are in bounds. - - SCAN_START is the first instruction in the loop, as the loop would - actually be executed. END is the NOTE_INSN_LOOP_END. LOOP_TOP is - the first instruction in the loop, as it is layed out in the - instruction stream. LOOP_START is the NOTE_INSN_LOOP_BEG. - LOOP_CONT is the NOTE_INSN_LOOP_CONT. */ +/* Scan the loop body and call FNCALL for each insn. In the addition to the + LOOP and INSN parameters pass MAYBE_MULTIPLE and NOT_EVERY_ITERATION to the + callback. -static void -strength_reduce (scan_start, end, loop_top, insn_count, - loop_start, loop_end, loop_cont, unroll_p, bct_p) - rtx scan_start; - rtx end; - rtx loop_top; - int insn_count; - rtx loop_start; - rtx loop_end; - rtx loop_cont; - int unroll_p, bct_p ATTRIBUTE_UNUSED; + NOT_EVERY_ITERATION if current insn is not executed at least once for every + loop iteration except for the last one. + + MAYBE_MULTIPLE is 1 if current insn may be executed more than once for every + loop iteration. + */ +void +for_each_insn_in_loop (loop, fncall) + struct loop *loop; + loop_insn_callback fncall; { - rtx p; - rtx set; - rtx inc_val; - rtx mult_val; - rtx dest_reg; - rtx *location; /* This is 1 if current insn is not executed at least once for every loop iteration. */ int not_every_iteration = 0; - /* This is 1 if current insn may be executed more than once for every - loop iteration. */ int maybe_multiple = 0; - /* This is 1 if we have past a branch back to the top of the loop - (aka a loop latch). */ int past_loop_latch = 0; - /* Temporary list pointers for traversing loop_iv_list. */ - struct iv_class *bl, **backbl; - /* Ratio of extra register life span we can justify - for saving an instruction. More if loop doesn't call subroutines - since in that case saving an insn makes more difference - and more registers are available. */ - /* ??? could set this to last value of threshold in move_movables */ - int threshold = (loop_has_call ? 1 : 2) * (3 + n_non_fixed_regs); - /* Map of pseudo-register replacements. */ - rtx *reg_map; - int reg_map_size; - int call_seen; - rtx test; - rtx end_insert_before; int loop_depth = 0; - int n_extra_increment; - struct loop_info loop_iteration_info; - struct loop_info *loop_info = &loop_iteration_info; + rtx p; - /* If scan_start points to the loop exit test, we have to be wary of + /* If loop_scan_start points to the loop exit test, we have to be wary of subversive use of gotos inside expression statements. */ - if (prev_nonnote_insn (scan_start) != prev_nonnote_insn (loop_start)) - maybe_multiple = back_branch_in_range_p (scan_start, loop_start, loop_end); - - VARRAY_INT_INIT (reg_iv_type, max_reg_before_loop, "reg_iv_type"); - VARRAY_GENERIC_PTR_INIT (reg_iv_info, max_reg_before_loop, "reg_iv_info"); - reg_biv_class = (struct iv_class **) - alloca (max_reg_before_loop * sizeof (struct iv_class *)); - bzero ((char *) reg_biv_class, (max_reg_before_loop - * sizeof (struct iv_class *))); - - loop_iv_list = 0; - addr_placeholder = gen_reg_rtx (Pmode); - - /* Save insn immediately after the loop_end. Insns inserted after loop_end - must be put before this insn, so that they will appear in the right - order (i.e. loop order). - - If loop_end is the end of the current function, then emit a - NOTE_INSN_DELETED after loop_end and set end_insert_before to the - dummy note insn. */ - if (NEXT_INSN (loop_end) != 0) - end_insert_before = NEXT_INSN (loop_end); - else - end_insert_before = emit_note_after (NOTE_INSN_DELETED, loop_end); + if (prev_nonnote_insn (loop->scan_start) != prev_nonnote_insn (loop->start)) + maybe_multiple = back_branch_in_range_p (loop, loop->scan_start); /* Scan through loop to find all possible bivs. */ - for (p = next_insn_in_loop (scan_start, scan_start, end, loop_top); + for (p = next_insn_in_loop (loop, loop->scan_start); p != NULL_RTX; - p = next_insn_in_loop (p, scan_start, end, loop_top)) + p = next_insn_in_loop (loop, p)) { - if (GET_CODE (p) == INSN - && (set = single_set (p)) - && GET_CODE (SET_DEST (set)) == REG) - { - dest_reg = SET_DEST (set); - if (REGNO (dest_reg) < max_reg_before_loop - && REGNO (dest_reg) >= FIRST_PSEUDO_REGISTER - && REG_IV_TYPE (REGNO (dest_reg)) != NOT_BASIC_INDUCT) - { - if (basic_induction_var (SET_SRC (set), GET_MODE (SET_SRC (set)), - dest_reg, p, &inc_val, &mult_val, - &location)) - { - /* It is a possible basic induction variable. - Create and initialize an induction structure for it. */ - - struct induction *v - = (struct induction *) alloca (sizeof (struct induction)); - - record_biv (v, p, dest_reg, inc_val, mult_val, location, - not_every_iteration, maybe_multiple); - REG_IV_TYPE (REGNO (dest_reg)) = BASIC_INDUCT; - } - else if (REGNO (dest_reg) < max_reg_before_loop) - REG_IV_TYPE (REGNO (dest_reg)) = NOT_BASIC_INDUCT; - } - } + p = fncall (loop, p, not_every_iteration, maybe_multiple); /* Past CODE_LABEL, we get to insns that may be executed multiple - times. The only way we can be sure that they can't is if every - jump insn between here and the end of the loop either - returns, exits the loop, is a jump to a location that is still - behind the label, or is a jump to the loop start. */ + times. The only way we can be sure that they can't is if every + jump insn between here and the end of the loop either + returns, exits the loop, is a jump to a location that is still + behind the label, or is a jump to the loop start. */ if (GET_CODE (p) == CODE_LABEL) { @@ -3831,24 +4168,24 @@ strength_reduce (scan_start, end, loop_top, insn_count, while (1) { insn = NEXT_INSN (insn); - if (insn == scan_start) + if (insn == loop->scan_start) break; - if (insn == end) + if (insn == loop->end) { - if (loop_top != 0) - insn = loop_top; + if (loop->top != 0) + insn = loop->top; else break; - if (insn == scan_start) + if (insn == loop->scan_start) break; } if (GET_CODE (insn) == JUMP_INSN && GET_CODE (PATTERN (insn)) != RETURN - && (! condjump_p (insn) + && (!any_condjump_p (insn) || (JUMP_LABEL (insn) != 0 - && JUMP_LABEL (insn) != scan_start - && ! loop_insn_first_p (p, JUMP_LABEL (insn))))) + && JUMP_LABEL (insn) != loop->scan_start + && !loop_insn_first_p (p, JUMP_LABEL (insn))))) { maybe_multiple = 1; break; @@ -3857,31 +4194,30 @@ strength_reduce (scan_start, end, loop_top, insn_count, } /* Past a jump, we get to insns for which we can't count - on whether they will be executed during each iteration. */ + on whether they will be executed during each iteration. */ /* This code appears twice in strength_reduce. There is also similar - code in scan_loop. */ + code in scan_loop. */ if (GET_CODE (p) == JUMP_INSN - /* If we enter the loop in the middle, and scan around to the - beginning, don't set not_every_iteration for that. - This can be any kind of jump, since we want to know if insns - will be executed if the loop is executed. */ - && ! (JUMP_LABEL (p) == loop_top - && ((NEXT_INSN (NEXT_INSN (p)) == loop_end && simplejump_p (p)) - || (NEXT_INSN (p) == loop_end && condjump_p (p))))) + /* If we enter the loop in the middle, and scan around to the + beginning, don't set not_every_iteration for that. + This can be any kind of jump, since we want to know if insns + will be executed if the loop is executed. */ + && !(JUMP_LABEL (p) == loop->top + && ((NEXT_INSN (NEXT_INSN (p)) == loop->end + && any_uncondjump_p (p)) + || (NEXT_INSN (p) == loop->end && any_condjump_p (p))))) { rtx label = 0; /* If this is a jump outside the loop, then it also doesn't matter. Check to see if the target of this branch is on the - loop_number_exits_labels list. */ - - for (label = loop_number_exit_labels[uid_loop_num[INSN_UID (loop_start)]]; - label; - label = LABEL_NEXTREF (label)) + loop->exits_labels list. */ + + for (label = loop->exit_labels; label; label = LABEL_NEXTREF (label)) if (XEXP (label, 0) == JUMP_LABEL (p)) break; - if (! label) + if (!label) not_every_iteration = 1; } @@ -3904,55 +4240,70 @@ strength_reduce (scan_start, end, loop_top, insn_count, } /* Note if we pass a loop latch. If we do, then we can not clear - NOT_EVERY_ITERATION below when we pass the last CODE_LABEL in - a loop since a jump before the last CODE_LABEL may have started - a new loop iteration. - - Note that LOOP_TOP is only set for rotated loops and we need - this check for all loops, so compare against the CODE_LABEL - which immediately follows LOOP_START. */ - if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) == NEXT_INSN (loop_start)) + NOT_EVERY_ITERATION below when we pass the last CODE_LABEL in + a loop since a jump before the last CODE_LABEL may have started + a new loop iteration. + + Note that LOOP_TOP is only set for rotated loops and we need + this check for all loops, so compare against the CODE_LABEL + which immediately follows LOOP_START. */ + if (GET_CODE (p) == JUMP_INSN + && JUMP_LABEL (p) == NEXT_INSN (loop->start)) past_loop_latch = 1; /* Unlike in the code motion pass where MAYBE_NEVER indicates that - an insn may never be executed, NOT_EVERY_ITERATION indicates whether - or not an insn is known to be executed each iteration of the - loop, whether or not any iterations are known to occur. + an insn may never be executed, NOT_EVERY_ITERATION indicates whether + or not an insn is known to be executed each iteration of the + loop, whether or not any iterations are known to occur. - Therefore, if we have just passed a label and have no more labels - between here and the test insn of the loop, and we have not passed - a jump to the top of the loop, then we know these insns will be - executed each iteration. */ + Therefore, if we have just passed a label and have no more labels + between here and the test insn of the loop, and we have not passed + a jump to the top of the loop, then we know these insns will be + executed each iteration. */ - if (not_every_iteration - && ! past_loop_latch + if (not_every_iteration + && !past_loop_latch && GET_CODE (p) == CODE_LABEL - && no_labels_between_p (p, loop_end) - && loop_insn_first_p (p, loop_cont)) + && no_labels_between_p (p, loop->end) + && loop_insn_first_p (p, loop->cont)) not_every_iteration = 0; } +} + +static void +loop_bivs_find (loop) + struct loop *loop; +{ + struct loop_regs *regs = LOOP_REGS (loop); + struct loop_ivs *ivs = LOOP_IVS (loop); + /* Temporary list pointers for traversing ivs->list. */ + struct iv_class *bl, **backbl; + + ivs->list = 0; - /* Scan loop_iv_list to remove all regs that proved not to be bivs. - Make a sanity check against n_times_set. */ - for (backbl = &loop_iv_list, bl = *backbl; bl; bl = bl->next) + for_each_insn_in_loop (loop, check_insn_for_bivs); + + /* Scan ivs->list to remove all regs that proved not to be bivs. + Make a sanity check against regs->n_times_set. */ + for (backbl = &ivs->list, bl = *backbl; bl; bl = bl->next) { - if (REG_IV_TYPE (bl->regno) != BASIC_INDUCT + if (REG_IV_TYPE (ivs, bl->regno) != BASIC_INDUCT /* Above happens if register modified by subreg, etc. */ /* Make sure it is not recognized as a basic induction var: */ - || VARRAY_INT (n_times_set, bl->regno) != bl->biv_count + || regs->array[bl->regno].n_times_set != bl->biv_count /* If never incremented, it is invariant that we decided not to move. So leave it alone. */ || ! bl->incremented) { if (loop_dump_stream) - fprintf (loop_dump_stream, "Reg %d: biv discarded, %s\n", + fprintf (loop_dump_stream, "Biv %d: discarded, %s\n", bl->regno, - (REG_IV_TYPE (bl->regno) != BASIC_INDUCT + (REG_IV_TYPE (ivs, bl->regno) != BASIC_INDUCT ? "not induction variable" : (! bl->incremented ? "never incremented" : "count error"))); - - REG_IV_TYPE (bl->regno) = NOT_BASIC_INDUCT; + + REG_IV_TYPE (ivs, bl->regno) = NOT_BASIC_INDUCT; *backbl = bl->next; } else @@ -3960,48 +4311,51 @@ strength_reduce (scan_start, end, loop_top, insn_count, backbl = &bl->next; if (loop_dump_stream) - fprintf (loop_dump_stream, "Reg %d: biv verified\n", bl->regno); + fprintf (loop_dump_stream, "Biv %d: verified\n", bl->regno); } } +} - /* Exit if there are no bivs. */ - if (! loop_iv_list) - { - /* Can still unroll the loop anyways, but indicate that there is no - strength reduction info available. */ - if (unroll_p) - unroll_loop (loop_end, insn_count, loop_start, end_insert_before, - loop_info, 0); - return; - } +/* Determine how BIVS are initialised by looking through pre-header + extended basic block. */ +static void +loop_bivs_init_find (loop) + struct loop *loop; +{ + struct loop_ivs *ivs = LOOP_IVS (loop); + /* Temporary list pointers for traversing ivs->list. */ + struct iv_class *bl; + int call_seen; + rtx p; /* Find initial value for each biv by searching backwards from loop_start, halting at first label. Also record any test condition. */ call_seen = 0; - for (p = loop_start; p && GET_CODE (p) != CODE_LABEL; p = PREV_INSN (p)) + for (p = loop->start; p && GET_CODE (p) != CODE_LABEL; p = PREV_INSN (p)) { + rtx test; + note_insn = p; if (GET_CODE (p) == CALL_INSN) call_seen = 1; - if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN - || GET_CODE (p) == CALL_INSN) - note_stores (PATTERN (p), record_initial); + if (INSN_P (p)) + note_stores (PATTERN (p), record_initial, ivs); /* Record any test of a biv that branches around the loop if no store between it and the start of loop. We only care about tests with constants and registers and only certain of those. */ if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) != 0 - && next_real_insn (JUMP_LABEL (p)) == next_real_insn (loop_end) - && (test = get_condition_for_loop (p)) != 0 + && next_real_insn (JUMP_LABEL (p)) == next_real_insn (loop->end) + && (test = get_condition_for_loop (loop, p)) != 0 && GET_CODE (XEXP (test, 0)) == REG && REGNO (XEXP (test, 0)) < max_reg_before_loop - && (bl = reg_biv_class[REGNO (XEXP (test, 0))]) != 0 - && valid_initial_value_p (XEXP (test, 1), p, call_seen, loop_start) + && (bl = REG_IV_CLASS (ivs, REGNO (XEXP (test, 0)))) != 0 + && valid_initial_value_p (XEXP (test, 1), p, call_seen, loop->start) && bl->init_insn == 0) { /* If an NE test, we have an initial value! */ @@ -4015,11 +4369,22 @@ strength_reduce (scan_start, end, loop_top, insn_count, bl->initial_test = test; } } +} - /* Look at the each biv and see if we can say anything better about its - initial value from any initializing insns set up above. (This is done - in two passes to avoid missing SETs in a PARALLEL.) */ - for (backbl = &loop_iv_list; (bl = *backbl); backbl = &bl->next) + +/* Look at the each biv and see if we can say anything better about its + initial value from any initializing insns set up above. (This is done + in two passes to avoid missing SETs in a PARALLEL.) */ +static void +loop_bivs_check (loop) + struct loop *loop; +{ + struct loop_ivs *ivs = LOOP_IVS (loop); + /* Temporary list pointers for traversing ivs->list. */ + struct iv_class *bl; + struct iv_class **backbl; + + for (backbl = &ivs->list; (bl = *backbl); backbl = &bl->next) { rtx src; rtx note; @@ -4039,639 +4404,608 @@ strength_reduce (scan_start, end, loop_top, insn_count, if (loop_dump_stream) fprintf (loop_dump_stream, - "Biv %d initialized at insn %d: initial value ", + "Biv %d: initialized at insn %d: initial value ", bl->regno, INSN_UID (bl->init_insn)); if ((GET_MODE (src) == GET_MODE (regno_reg_rtx[bl->regno]) || GET_MODE (src) == VOIDmode) - && valid_initial_value_p (src, bl->init_insn, call_seen, loop_start)) + && valid_initial_value_p (src, bl->init_insn, + LOOP_INFO (loop)->pre_header_has_call, + loop->start)) { bl->initial_value = src; if (loop_dump_stream) { - if (GET_CODE (src) == CONST_INT) - { - fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, INTVAL (src)); - fputc ('\n', loop_dump_stream); - } - else - { - print_rtl (loop_dump_stream, src); - fprintf (loop_dump_stream, "\n"); - } + print_simple_rtl (loop_dump_stream, src); + fputc ('\n', loop_dump_stream); } } - else - { - struct iv_class *bl2 = 0; - rtx increment; - - /* Biv initial value is not a simple move. If it is the sum of - another biv and a constant, check if both bivs are incremented - in lockstep. Then we are actually looking at a giv. - For simplicity, we only handle the case where there is but a - single increment, and the register is not used elsewhere. */ - if (bl->biv_count == 1 - && bl->regno < max_reg_before_loop - && uid_luid[REGNO_LAST_UID (bl->regno)] < INSN_LUID (loop_end) - && GET_CODE (src) == PLUS - && GET_CODE (XEXP (src, 0)) == REG - && CONSTANT_P (XEXP (src, 1)) - && ((increment = biv_total_increment (bl, loop_start, loop_end)) - != NULL_RTX)) - { - int regno = REGNO (XEXP (src, 0)); + /* If we can't make it a giv, + let biv keep initial value of "itself". */ + else if (loop_dump_stream) + fprintf (loop_dump_stream, "is complex\n"); + } +} - for (bl2 = loop_iv_list; bl2; bl2 = bl2->next) - if (bl2->regno == regno) - break; - } - - /* Now, can we transform this biv into a giv? */ - if (bl2 - && bl2->biv_count == 1 - && rtx_equal_p (increment, - biv_total_increment (bl2, loop_start, loop_end)) - /* init_insn is only set to insns that are before loop_start - without any intervening labels. */ - && ! reg_set_between_p (bl2->biv->src_reg, - PREV_INSN (bl->init_insn), loop_start) - /* The register from BL2 must be set before the register from - BL is set, or we must be able to move the latter set after - the former set. Currently there can't be any labels - in-between when biv_toal_increment returns nonzero both times - but we test it here in case some day some real cfg analysis - gets used to set always_computable. */ - && ((loop_insn_first_p (bl2->biv->insn, bl->biv->insn) - && no_labels_between_p (bl2->biv->insn, bl->biv->insn)) - || (! reg_used_between_p (bl->biv->src_reg, bl->biv->insn, - bl2->biv->insn) - && no_jumps_between_p (bl->biv->insn, bl2->biv->insn))) - && validate_change (bl->biv->insn, - &SET_SRC (single_set (bl->biv->insn)), - copy_rtx (src), 0)) - { - int loop_num = uid_loop_num[INSN_UID (loop_start)]; - rtx dominator = loop_number_cont_dominator[loop_num]; - rtx giv = bl->biv->src_reg; - rtx giv_insn = bl->biv->insn; - rtx after_giv = NEXT_INSN (giv_insn); - if (loop_dump_stream) - fprintf (loop_dump_stream, "is giv of biv %d\n", bl2->regno); - /* Let this giv be discovered by the generic code. */ - REG_IV_TYPE (bl->regno) = UNKNOWN_INDUCT; - /* We can get better optimization if we can move the giv setting - before the first giv use. */ - if (dominator - && ! loop_insn_first_p (dominator, scan_start) - && ! reg_set_between_p (bl2->biv->src_reg, loop_start, - dominator) - && ! reg_used_between_p (giv, loop_start, dominator) - && ! reg_used_between_p (giv, giv_insn, loop_end)) - { - rtx p; - rtx next; +/* Search the loop for general induction variables. */ - for (next = NEXT_INSN (dominator); ; next = NEXT_INSN (next)) - { - if ((GET_RTX_CLASS (GET_CODE (next)) == 'i' - && (reg_mentioned_p (giv, PATTERN (next)) - || reg_set_p (bl2->biv->src_reg, next))) - || GET_CODE (next) == JUMP_INSN) - break; -#ifdef HAVE_cc0 - if (GET_RTX_CLASS (GET_CODE (next)) != 'i' - || ! sets_cc0_p (PATTERN (next))) -#endif - dominator = next; - } - if (loop_dump_stream) - fprintf (loop_dump_stream, "move after insn %d\n", - INSN_UID (dominator)); - /* Avoid problems with luids by actually moving the insn - and adjusting all luids in the range. */ - reorder_insns (giv_insn, giv_insn, dominator); - for (p = dominator; INSN_UID (p) >= max_uid_for_loop; ) - p = PREV_INSN (p); - compute_luids (giv_insn, after_giv, INSN_LUID (p)); - /* If the only purpose of the init insn is to initialize - this giv, delete it. */ - if (single_set (bl->init_insn) - && ! reg_used_between_p (giv, bl->init_insn, loop_start)) - delete_insn (bl->init_insn); - } - else if (! loop_insn_first_p (bl2->biv->insn, bl->biv->insn)) - { - rtx p = PREV_INSN (giv_insn); - while (INSN_UID (p) >= max_uid_for_loop) - p = PREV_INSN (p); - reorder_insns (giv_insn, giv_insn, bl2->biv->insn); - compute_luids (after_giv, NEXT_INSN (giv_insn), - INSN_LUID (p)); - } - /* Remove this biv from the chain. */ - if (bl->next) - *bl = *bl->next; - else - { - *backbl = 0; - break; - } - } +static void +loop_givs_find (loop) + struct loop* loop; +{ + for_each_insn_in_loop (loop, check_insn_for_givs); +} - /* If we can't make it a giv, - let biv keep initial value of "itself". */ - else if (loop_dump_stream) - fprintf (loop_dump_stream, "is complex\n"); - } + +/* For each giv for which we still don't know whether or not it is + replaceable, check to see if it is replaceable because its final value + can be calculated. */ + +static void +loop_givs_check (loop) + struct loop *loop; +{ + struct loop_ivs *ivs = LOOP_IVS (loop); + struct iv_class *bl; + + for (bl = ivs->list; bl; bl = bl->next) + { + struct induction *v; + + for (v = bl->giv; v; v = v->next_iv) + if (! v->replaceable && ! v->not_replaceable) + check_final_value (loop, v); } +} - /* If a biv is unconditionally incremented several times in a row, convert - all but the last increment into a giv. */ - /* Get an upper bound for the number of registers - we might have after all bivs have been processed. */ - first_increment_giv = max_reg_num (); - for (n_extra_increment = 0, bl = loop_iv_list; bl; bl = bl->next) - n_extra_increment += bl->biv_count - 1; +/* Return non-zero if it is possible to eliminate the biv BL provided + all givs are reduced. This is possible if either the reg is not + used outside the loop, or we can compute what its final value will + be. */ - /* If the loop contains volatile memory references do not allow any - replacements to take place, since this could loose the volatile - markers. +static int +loop_biv_eliminable_p (loop, bl, threshold, insn_count) + struct loop *loop; + struct iv_class *bl; + int threshold; + int insn_count; +{ + /* For architectures with a decrement_and_branch_until_zero insn, + don't do this if we put a REG_NONNEG note on the endtest for this + biv. */ + +#ifdef HAVE_decrement_and_branch_until_zero + if (bl->nonneg) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, + "Cannot eliminate nonneg biv %d.\n", bl->regno); + return 0; + } +#endif - Disabled for the gcc-2.95 release. There are still some problems with - giv recombination. We have a patch from Joern which should fix those - problems. But the patch is fairly complex and not really suitable for - the gcc-2.95 branch at this stage. */ - if (0 && n_extra_increment && ! loop_has_volatile) + /* Check that biv is used outside loop or if it has a final value. + Compare against bl->init_insn rather than loop->start. We aren't + concerned with any uses of the biv between init_insn and + loop->start since these won't be affected by the value of the biv + elsewhere in the function, so long as init_insn doesn't use the + biv itself. */ + + if ((REGNO_LAST_LUID (bl->regno) < INSN_LUID (loop->end) + && bl->init_insn + && INSN_UID (bl->init_insn) < max_uid_for_loop + && REGNO_FIRST_LUID (bl->regno) >= INSN_LUID (bl->init_insn) + && ! reg_mentioned_p (bl->biv->dest_reg, SET_SRC (bl->init_set))) + || (bl->final_value = final_biv_value (loop, bl))) + return maybe_eliminate_biv (loop, bl, 0, threshold, insn_count); + if (loop_dump_stream) { - int nregs = first_increment_giv + n_extra_increment; + fprintf (loop_dump_stream, + "Cannot eliminate biv %d.\n", + bl->regno); + fprintf (loop_dump_stream, + "First use: insn %d, last use: insn %d.\n", + REGNO_FIRST_UID (bl->regno), + REGNO_LAST_UID (bl->regno)); + } + return 0; +} - /* Reallocate reg_iv_type and reg_iv_info. */ - VARRAY_GROW (reg_iv_type, nregs); - VARRAY_GROW (reg_iv_info, nregs); - for (bl = loop_iv_list; bl; bl = bl->next) - { - struct induction **vp, *v, *next; - int biv_dead_after_loop = 0; +/* Reduce each giv of BL that we have decided to reduce. */ - /* The biv increments lists are in reverse order. Fix this first. */ - for (v = bl->biv, bl->biv = 0; v; v = next) - { - next = v->next_iv; - v->next_iv = bl->biv; - bl->biv = v; - } +static void +loop_givs_reduce (loop, bl) + struct loop *loop; + struct iv_class *bl; +{ + struct induction *v; - /* We must guard against the case that an early exit between v->insn - and next->insn leaves the biv live after the loop, since that - would mean that we'd be missing an increment for the final - value. The following test to set biv_dead_after_loop is like - the first part of the test to set bl->eliminable. - We don't check here if we can calculate the final value, since - this can't succeed if we already know that there is a jump - between v->insn and next->insn, yet next->always_executed is - set and next->maybe_multiple is cleared. Such a combination - implies that the jump destination is outside the loop. - If we want to make this check more sophisticated, we should - check each branch between v->insn and next->insn individually - to see if the biv is dead at its destination. */ - - if (uid_luid[REGNO_LAST_UID (bl->regno)] < INSN_LUID (loop_end) - && bl->init_insn - && INSN_UID (bl->init_insn) < max_uid_for_loop - && (uid_luid[REGNO_FIRST_UID (bl->regno)] - >= INSN_LUID (bl->init_insn)) -#ifdef HAVE_decrement_and_branch_until_zero - && ! bl->nonneg -#endif - && ! reg_mentioned_p (bl->biv->dest_reg, SET_SRC (bl->init_set))) - biv_dead_after_loop = 1; + for (v = bl->giv; v; v = v->next_iv) + { + struct induction *tv; + if (! v->ignore && v->same == 0) + { + int auto_inc_opt = 0; - for (vp = &bl->biv, next = *vp; v = next, next = v->next_iv;) + /* If the code for derived givs immediately below has already + allocated a new_reg, we must keep it. */ + if (! v->new_reg) + v->new_reg = gen_reg_rtx (v->mode); + +#ifdef AUTO_INC_DEC + /* If the target has auto-increment addressing modes, and + this is an address giv, then try to put the increment + immediately after its use, so that flow can create an + auto-increment addressing mode. */ + if (v->giv_type == DEST_ADDR && bl->biv_count == 1 + && bl->biv->always_executed && ! bl->biv->maybe_multiple + /* We don't handle reversed biv's because bl->biv->insn + does not have a valid INSN_LUID. */ + && ! bl->reversed + && v->always_executed && ! v->maybe_multiple + && INSN_UID (v->insn) < max_uid_for_loop) { - HOST_WIDE_INT offset; - rtx set, add_val, old_reg, dest_reg, last_use_insn; - int old_regno, new_regno; - - if (! v->always_executed - || v->maybe_multiple - || GET_CODE (v->add_val) != CONST_INT - || ! next->always_executed - || next->maybe_multiple - || ! CONSTANT_P (next->add_val) - || v->mult_val != const1_rtx - || next->mult_val != const1_rtx - || ! (biv_dead_after_loop - || no_jumps_between_p (v->insn, next->insn))) - { - vp = &v->next_iv; - continue; - } - offset = INTVAL (v->add_val); - set = single_set (v->insn); - add_val = plus_constant (next->add_val, offset); - old_reg = v->dest_reg; - dest_reg = gen_reg_rtx (v->mode); - - /* Unlike reg_iv_type / reg_iv_info, the other three arrays - have been allocated with some slop space, so we may not - actually need to reallocate them. If we do, the following - if statement will be executed just once in this loop. */ - if ((unsigned) max_reg_num () > n_times_set->num_elements) + /* If other giv's have been combined with this one, then + this will work only if all uses of the other giv's occur + before this giv's insn. This is difficult to check. + + We simplify this by looking for the common case where + there is one DEST_REG giv, and this giv's insn is the + last use of the dest_reg of that DEST_REG giv. If the + increment occurs after the address giv, then we can + perform the optimization. (Otherwise, the increment + would have to go before other_giv, and we would not be + able to combine it with the address giv to get an + auto-inc address.) */ + if (v->combined_with) { - /* Grow all the remaining arrays. */ - VARRAY_GROW (set_in_loop, nregs); - VARRAY_GROW (n_times_set, nregs); - VARRAY_GROW (may_not_optimize, nregs); - VARRAY_GROW (reg_single_usage, nregs); - } - - if (! validate_change (next->insn, next->location, add_val, 0)) - { - vp = &v->next_iv; - continue; - } + struct induction *other_giv = 0; - /* Here we can try to eliminate the increment by combining - it into the uses. */ + for (tv = bl->giv; tv; tv = tv->next_iv) + if (tv->same == v) + { + if (other_giv) + break; + else + other_giv = tv; + } + if (! tv && other_giv + && REGNO (other_giv->dest_reg) < max_reg_before_loop + && (REGNO_LAST_UID (REGNO (other_giv->dest_reg)) + == INSN_UID (v->insn)) + && INSN_LUID (v->insn) < INSN_LUID (bl->biv->insn)) + auto_inc_opt = 1; + } + /* Check for case where increment is before the address + giv. Do this test in "loop order". */ + else if ((INSN_LUID (v->insn) > INSN_LUID (bl->biv->insn) + && (INSN_LUID (v->insn) < INSN_LUID (loop->scan_start) + || (INSN_LUID (bl->biv->insn) + > INSN_LUID (loop->scan_start)))) + || (INSN_LUID (v->insn) < INSN_LUID (loop->scan_start) + && (INSN_LUID (loop->scan_start) + < INSN_LUID (bl->biv->insn)))) + auto_inc_opt = -1; + else + auto_inc_opt = 1; - /* Set last_use_insn so that we can check against it. */ +#ifdef HAVE_cc0 + { + rtx prev; + + /* We can't put an insn immediately after one setting + cc0, or immediately before one using cc0. */ + if ((auto_inc_opt == 1 && sets_cc0_p (PATTERN (v->insn))) + || (auto_inc_opt == -1 + && (prev = prev_nonnote_insn (v->insn)) != 0 + && INSN_P (prev) + && sets_cc0_p (PATTERN (prev)))) + auto_inc_opt = 0; + } +#endif - for (last_use_insn = v->insn, p = NEXT_INSN (v->insn); - p != next->insn; - p = next_insn_in_loop (p, scan_start, end, loop_top)) - { - if (GET_RTX_CLASS (GET_CODE (p)) != 'i') - continue; - if (reg_mentioned_p (old_reg, PATTERN (p))) - { - last_use_insn = p; - } - } + if (auto_inc_opt) + v->auto_inc_opt = 1; + } +#endif - /* If we can't get the LUIDs for the insns, we can't - calculate the lifetime. This is likely from unrolling - of an inner loop, so there is little point in making this - a DEST_REG giv anyways. */ - if (INSN_UID (v->insn) >= max_uid_for_loop - || INSN_UID (last_use_insn) >= max_uid_for_loop - || ! validate_change (v->insn, &SET_DEST (set), dest_reg, 0)) - { - /* Change the increment at NEXT back to what it was. */ - if (! validate_change (next->insn, next->location, - next->add_val, 0)) - abort (); - vp = &v->next_iv; - continue; - } - next->add_val = add_val; - v->dest_reg = dest_reg; - v->giv_type = DEST_REG; - v->location = &SET_SRC (set); - v->cant_derive = 0; - v->combined_with = 0; - v->maybe_dead = 0; - v->derive_adjustment = 0; - v->same = 0; - v->ignore = 0; - v->new_reg = 0; - v->final_value = 0; - v->same_insn = 0; - v->auto_inc_opt = 0; - v->unrolled = 0; - v->shared = 0; - v->derived_from = 0; - v->always_computable = 1; - v->always_executed = 1; - v->replaceable = 1; - v->no_const_addval = 0; - - old_regno = REGNO (old_reg); - new_regno = REGNO (dest_reg); - VARRAY_INT (set_in_loop, old_regno)--; - VARRAY_INT (set_in_loop, new_regno) = 1; - VARRAY_INT (n_times_set, old_regno)--; - VARRAY_INT (n_times_set, new_regno) = 1; - VARRAY_CHAR (may_not_optimize, new_regno) = 0; - - REG_IV_TYPE (new_regno) = GENERAL_INDUCT; - REG_IV_INFO (new_regno) = v; - - /* Remove the increment from the list of biv increments, - and record it as a giv. */ - *vp = next; - bl->biv_count--; - v->next_iv = bl->giv; - bl->giv = v; - bl->giv_count++; - v->benefit = rtx_cost (SET_SRC (set), SET); - bl->total_benefit += v->benefit; - - /* Now replace the biv with DEST_REG in all insns between - the replaced increment and the next increment, and - remember the last insn that needed a replacement. */ - for (last_use_insn = v->insn, p = NEXT_INSN (v->insn); - p != next->insn; - p = next_insn_in_loop (p, scan_start, end, loop_top)) - { - rtx note; - - if (GET_RTX_CLASS (GET_CODE (p)) != 'i') - continue; - if (reg_mentioned_p (old_reg, PATTERN (p))) - { - last_use_insn = p; - if (! validate_replace_rtx (old_reg, dest_reg, p)) - abort (); - } - for (note = REG_NOTES (p); note; note = XEXP (note, 1)) - { - if (GET_CODE (note) == EXPR_LIST) - XEXP (note, 0) - = replace_rtx (XEXP (note, 0), old_reg, dest_reg); - } - } - - v->last_use = last_use_insn; - v->lifetime = INSN_LUID (v->insn) - INSN_LUID (last_use_insn); - /* If the lifetime is zero, it means that this register is really - a dead store. So mark this as a giv that can be ignored. - This will not prevent the biv from being eliminated. */ - if (v->lifetime == 0) - v->ignore = 1; + /* For each place where the biv is incremented, add an insn + to increment the new, reduced reg for the giv. */ + for (tv = bl->biv; tv; tv = tv->next_iv) + { + rtx insert_before; - if (loop_dump_stream) - fprintf (loop_dump_stream, - "Increment %d of biv %d converted to giv %d.\n\n", - INSN_UID (v->insn), old_regno, new_regno); + if (! auto_inc_opt) + insert_before = tv->insn; + else if (auto_inc_opt == 1) + insert_before = NEXT_INSN (v->insn); + else + insert_before = v->insn; + + if (tv->mult_val == const1_rtx) + loop_iv_add_mult_emit_before (loop, tv->add_val, v->mult_val, + v->new_reg, v->new_reg, + 0, insert_before); + else /* tv->mult_val == const0_rtx */ + /* A multiply is acceptable here + since this is presumed to be seldom executed. */ + loop_iv_add_mult_emit_before (loop, tv->add_val, v->mult_val, + v->add_val, v->new_reg, + 0, insert_before); } + + /* Add code at loop start to initialize giv's reduced reg. */ + + loop_iv_add_mult_hoist (loop, + extend_value_for_giv (v, bl->initial_value), + v->mult_val, v->add_val, v->new_reg); } } - last_increment_giv = max_reg_num () - 1; +} - /* Search the loop for general induction variables. */ - /* A register is a giv if: it is only set once, it is a function of a - biv and a constant (or invariant), and it is not a biv. */ +/* Check for givs whose first use is their definition and whose + last use is the definition of another giv. If so, it is likely + dead and should not be used to derive another giv nor to + eliminate a biv. */ - not_every_iteration = 0; - loop_depth = 0; - p = scan_start; - while (1) +static void +loop_givs_dead_check (loop, bl) + struct loop *loop ATTRIBUTE_UNUSED; + struct iv_class *bl; +{ + struct induction *v; + + for (v = bl->giv; v; v = v->next_iv) { - p = NEXT_INSN (p); - /* At end of a straight-in loop, we are done. - At end of a loop entered at the bottom, scan the top. */ - if (p == scan_start) - break; - if (p == end) + if (v->ignore + || (v->same && v->same->ignore)) + continue; + + if (v->giv_type == DEST_REG + && REGNO_FIRST_UID (REGNO (v->dest_reg)) == INSN_UID (v->insn)) { - if (loop_top != 0) - p = loop_top; - else - break; - if (p == scan_start) - break; + struct induction *v1; + + for (v1 = bl->giv; v1; v1 = v1->next_iv) + if (REGNO_LAST_UID (REGNO (v->dest_reg)) == INSN_UID (v1->insn)) + v->maybe_dead = 1; } + } +} - /* Look for a general induction variable in a register. */ - if (GET_CODE (p) == INSN - && (set = single_set (p)) - && GET_CODE (SET_DEST (set)) == REG - && ! VARRAY_CHAR (may_not_optimize, REGNO (SET_DEST (set)))) - { - rtx src_reg; - rtx add_val; - rtx mult_val; - int benefit; - rtx regnote = 0; - rtx last_consec_insn; - - dest_reg = SET_DEST (set); - if (REGNO (dest_reg) < FIRST_PSEUDO_REGISTER) - continue; - if (/* SET_SRC is a giv. */ - (general_induction_var (SET_SRC (set), &src_reg, &add_val, - &mult_val, 0, &benefit) - /* Equivalent expression is a giv. */ - || ((regnote = find_reg_note (p, REG_EQUAL, NULL_RTX)) - && general_induction_var (XEXP (regnote, 0), &src_reg, - &add_val, &mult_val, 0, - &benefit))) - /* Don't try to handle any regs made by loop optimization. - We have nothing on them in regno_first_uid, etc. */ - && REGNO (dest_reg) < max_reg_before_loop - /* Don't recognize a BASIC_INDUCT_VAR here. */ - && dest_reg != src_reg - /* This must be the only place where the register is set. */ - && (VARRAY_INT (n_times_set, REGNO (dest_reg)) == 1 - /* or all sets must be consecutive and make a giv. */ - || (benefit = consec_sets_giv (benefit, p, - src_reg, dest_reg, - &add_val, &mult_val, - &last_consec_insn)))) - { - struct induction *v - = (struct induction *) alloca (sizeof (struct induction)); +static void +loop_givs_rescan (loop, bl, reg_map) + struct loop *loop; + struct iv_class *bl; + rtx *reg_map; +{ + struct induction *v; - /* If this is a library call, increase benefit. */ - if (find_reg_note (p, REG_RETVAL, NULL_RTX)) - benefit += libcall_benefit (p); + for (v = bl->giv; v; v = v->next_iv) + { + if (v->same && v->same->ignore) + v->ignore = 1; - /* Skip the consecutive insns, if there are any. */ - if (VARRAY_INT (n_times_set, REGNO (dest_reg)) != 1) - p = last_consec_insn; + if (v->ignore) + continue; - record_giv (v, p, src_reg, dest_reg, mult_val, add_val, benefit, - DEST_REG, not_every_iteration, NULL_PTR, loop_start, - loop_end); + /* Update expression if this was combined, in case other giv was + replaced. */ + if (v->same) + v->new_reg = replace_rtx (v->new_reg, + v->same->dest_reg, v->same->new_reg); + + /* See if this register is known to be a pointer to something. If + so, see if we can find the alignment. First see if there is a + destination register that is a pointer. If so, this shares the + alignment too. Next see if we can deduce anything from the + computational information. If not, and this is a DEST_ADDR + giv, at least we know that it's a pointer, though we don't know + the alignment. */ + if (GET_CODE (v->new_reg) == REG + && v->giv_type == DEST_REG + && REG_POINTER (v->dest_reg)) + mark_reg_pointer (v->new_reg, + REGNO_POINTER_ALIGN (REGNO (v->dest_reg))); + else if (GET_CODE (v->new_reg) == REG + && REG_POINTER (v->src_reg)) + { + unsigned int align = REGNO_POINTER_ALIGN (REGNO (v->src_reg)); - } + if (align == 0 + || GET_CODE (v->add_val) != CONST_INT + || INTVAL (v->add_val) % (align / BITS_PER_UNIT) != 0) + align = 0; + + mark_reg_pointer (v->new_reg, align); } + else if (GET_CODE (v->new_reg) == REG + && GET_CODE (v->add_val) == REG + && REG_POINTER (v->add_val)) + { + unsigned int align = REGNO_POINTER_ALIGN (REGNO (v->add_val)); -#ifndef DONT_REDUCE_ADDR - /* Look for givs which are memory addresses. */ - /* This resulted in worse code on a VAX 8600. I wonder if it - still does. */ - if (GET_CODE (p) == INSN) - find_mem_givs (PATTERN (p), p, not_every_iteration, loop_start, - loop_end); -#endif + if (align == 0 || GET_CODE (v->mult_val) != CONST_INT + || INTVAL (v->mult_val) % (align / BITS_PER_UNIT) != 0) + align = 0; - /* Update the status of whether giv can derive other givs. This can - change when we pass a label or an insn that updates a biv. */ - if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN - || GET_CODE (p) == CODE_LABEL) - update_giv_derive (p); + mark_reg_pointer (v->new_reg, align); + } + else if (GET_CODE (v->new_reg) == REG && v->giv_type == DEST_ADDR) + mark_reg_pointer (v->new_reg, 0); - /* Past a jump, we get to insns for which we can't count - on whether they will be executed during each iteration. */ - /* This code appears twice in strength_reduce. There is also similar - code in scan_loop. */ - if (GET_CODE (p) == JUMP_INSN - /* If we enter the loop in the middle, and scan around to the - beginning, don't set not_every_iteration for that. - This can be any kind of jump, since we want to know if insns - will be executed if the loop is executed. */ - && ! (JUMP_LABEL (p) == loop_top - && ((NEXT_INSN (NEXT_INSN (p)) == loop_end && simplejump_p (p)) - || (NEXT_INSN (p) == loop_end && condjump_p (p))))) + if (v->giv_type == DEST_ADDR) + /* Store reduced reg as the address in the memref where we found + this giv. */ + validate_change (v->insn, v->location, v->new_reg, 0); + else if (v->replaceable) { - rtx label = 0; + reg_map[REGNO (v->dest_reg)] = v->new_reg; + } + else + { + /* Not replaceable; emit an insn to set the original giv reg from + the reduced giv, same as above. */ + loop_insn_emit_after (loop, 0, v->insn, + gen_move_insn (v->dest_reg, v->new_reg)); + } - /* If this is a jump outside the loop, then it also doesn't - matter. Check to see if the target of this branch is on the - loop_number_exits_labels list. */ - - for (label = loop_number_exit_labels[uid_loop_num[INSN_UID (loop_start)]]; - label; - label = LABEL_NEXTREF (label)) - if (XEXP (label, 0) == JUMP_LABEL (p)) - break; + /* When a loop is reversed, givs which depend on the reversed + biv, and which are live outside the loop, must be set to their + correct final value. This insn is only needed if the giv is + not replaceable. The correct final value is the same as the + value that the giv starts the reversed loop with. */ + if (bl->reversed && ! v->replaceable) + loop_iv_add_mult_sink (loop, + extend_value_for_giv (v, bl->initial_value), + v->mult_val, v->add_val, v->dest_reg); + else if (v->final_value) + loop_insn_sink_or_swim (loop, + gen_move_insn (v->dest_reg, v->final_value)); - if (! label) - not_every_iteration = 1; + if (loop_dump_stream) + { + fprintf (loop_dump_stream, "giv at %d reduced to ", + INSN_UID (v->insn)); + print_simple_rtl (loop_dump_stream, v->new_reg); + fprintf (loop_dump_stream, "\n"); } + } +} - else if (GET_CODE (p) == NOTE) - { - /* At the virtual top of a converted loop, insns are again known to - be executed each iteration: logically, the loop begins here - even though the exit code has been duplicated. - Insns are also again known to be executed each iteration at - the LOOP_CONT note. */ - if ((NOTE_LINE_NUMBER (p) == NOTE_INSN_LOOP_VTOP - || NOTE_LINE_NUMBER (p) == NOTE_INSN_LOOP_CONT) - && loop_depth == 0) - not_every_iteration = 0; - else if (NOTE_LINE_NUMBER (p) == NOTE_INSN_LOOP_BEG) - loop_depth++; - else if (NOTE_LINE_NUMBER (p) == NOTE_INSN_LOOP_END) - loop_depth--; +static int +loop_giv_reduce_benefit (loop, bl, v, test_reg) + struct loop *loop ATTRIBUTE_UNUSED; + struct iv_class *bl; + struct induction *v; + rtx test_reg; +{ + int add_cost; + int benefit; + + benefit = v->benefit; + PUT_MODE (test_reg, v->mode); + add_cost = iv_add_mult_cost (bl->biv->add_val, v->mult_val, + test_reg, test_reg); + + /* Reduce benefit if not replaceable, since we will insert a + move-insn to replace the insn that calculates this giv. Don't do + this unless the giv is a user variable, since it will often be + marked non-replaceable because of the duplication of the exit + code outside the loop. In such a case, the copies we insert are + dead and will be deleted. So they don't have a cost. Similar + situations exist. */ + /* ??? The new final_[bg]iv_value code does a much better job of + finding replaceable giv's, and hence this code may no longer be + necessary. */ + if (! v->replaceable && ! bl->eliminable + && REG_USERVAR_P (v->dest_reg)) + benefit -= copy_cost; + + /* Decrease the benefit to count the add-insns that we will insert + to increment the reduced reg for the giv. ??? This can + overestimate the run-time cost of the additional insns, e.g. if + there are multiple basic blocks that increment the biv, but only + one of these blocks is executed during each iteration. There is + no good way to detect cases like this with the current structure + of the loop optimizer. This code is more accurate for + determining code size than run-time benefits. */ + benefit -= add_cost * bl->biv_count; + + /* Decide whether to strength-reduce this giv or to leave the code + unchanged (recompute it from the biv each time it is used). This + decision can be made independently for each giv. */ + +#ifdef AUTO_INC_DEC + /* Attempt to guess whether autoincrement will handle some of the + new add insns; if so, increase BENEFIT (undo the subtraction of + add_cost that was done above). */ + if (v->giv_type == DEST_ADDR + /* Increasing the benefit is risky, since this is only a guess. + Avoid increasing register pressure in cases where there would + be no other benefit from reducing this giv. */ + && benefit > 0 + && GET_CODE (v->mult_val) == CONST_INT) + { + int size = GET_MODE_SIZE (GET_MODE (v->mem)); + + if (HAVE_POST_INCREMENT + && INTVAL (v->mult_val) == size) + benefit += add_cost * bl->biv_count; + else if (HAVE_PRE_INCREMENT + && INTVAL (v->mult_val) == size) + benefit += add_cost * bl->biv_count; + else if (HAVE_POST_DECREMENT + && -INTVAL (v->mult_val) == size) + benefit += add_cost * bl->biv_count; + else if (HAVE_PRE_DECREMENT + && -INTVAL (v->mult_val) == size) + benefit += add_cost * bl->biv_count; + } +#endif + + return benefit; +} + + +/* Free IV structures for LOOP. */ + +static void +loop_ivs_free (loop) + struct loop *loop; +{ + struct loop_ivs *ivs = LOOP_IVS (loop); + struct iv_class *iv = ivs->list; + + free (ivs->regs); + + while (iv) + { + struct iv_class *next = iv->next; + struct induction *induction; + struct induction *next_induction; + + for (induction = iv->biv; induction; induction = next_induction) + { + next_induction = induction->next_iv; + free (induction); + } + for (induction = iv->giv; induction; induction = next_induction) + { + next_induction = induction->next_iv; + free (induction); } - /* Unlike in the code motion pass where MAYBE_NEVER indicates that - an insn may never be executed, NOT_EVERY_ITERATION indicates whether - or not an insn is known to be executed each iteration of the - loop, whether or not any iterations are known to occur. + free (iv); + iv = next; + } +} - Therefore, if we have just passed a label and have no more labels - between here and the test insn of the loop, we know these insns - will be executed each iteration. */ - if (not_every_iteration && GET_CODE (p) == CODE_LABEL - && no_labels_between_p (p, loop_end) - && loop_insn_first_p (p, loop_cont)) - not_every_iteration = 0; +/* Perform strength reduction and induction variable elimination. + + Pseudo registers created during this function will be beyond the + last valid index in several tables including + REGS->ARRAY[I].N_TIMES_SET and REGNO_LAST_UID. This does not cause a + problem here, because the added registers cannot be givs outside of + their loop, and hence will never be reconsidered. But scan_loop + must check regnos to make sure they are in bounds. */ + +static void +strength_reduce (loop, flags) + struct loop *loop; + int flags; +{ + struct loop_info *loop_info = LOOP_INFO (loop); + struct loop_regs *regs = LOOP_REGS (loop); + struct loop_ivs *ivs = LOOP_IVS (loop); + rtx p; + /* Temporary list pointer for traversing ivs->list. */ + struct iv_class *bl; + /* Ratio of extra register life span we can justify + for saving an instruction. More if loop doesn't call subroutines + since in that case saving an insn makes more difference + and more registers are available. */ + /* ??? could set this to last value of threshold in move_movables */ + int threshold = (loop_info->has_call ? 1 : 2) * (3 + n_non_fixed_regs); + /* Map of pseudo-register replacements. */ + rtx *reg_map = NULL; + int reg_map_size; + int unrolled_insn_copies = 0; + rtx test_reg = gen_rtx_REG (word_mode, LAST_VIRTUAL_REGISTER + 1); + int insn_count = count_insns_in_loop (loop); + + addr_placeholder = gen_reg_rtx (Pmode); + + ivs->n_regs = max_reg_before_loop; + ivs->regs = (struct iv *) xcalloc (ivs->n_regs, sizeof (struct iv)); + + /* Find all BIVs in loop. */ + loop_bivs_find (loop); + + /* Exit if there are no bivs. */ + if (! ivs->list) + { + /* Can still unroll the loop anyways, but indicate that there is no + strength reduction info available. */ + if (flags & LOOP_UNROLL) + unroll_loop (loop, insn_count, 0); + + loop_ivs_free (loop); + return; } + /* Determine how BIVS are initialised by looking through pre-header + extended basic block. */ + loop_bivs_init_find (loop); + + /* Look at the each biv and see if we can say anything better about its + initial value from any initializing insns set up above. */ + loop_bivs_check (loop); + + /* Search the loop for general induction variables. */ + loop_givs_find (loop); + /* Try to calculate and save the number of loop iterations. This is set to zero if the actual number can not be calculated. This must be called after all giv's have been identified, since otherwise it may fail if the iteration variable is a giv. */ + loop_iterations (loop); - loop_iterations (loop_start, loop_end, loop_info); +#ifdef HAVE_prefetch + if (flags & LOOP_PREFETCH) + emit_prefetch_instructions (loop); +#endif /* Now for each giv for which we still don't know whether or not it is replaceable, check to see if it is replaceable because its final value can be calculated. This must be done after loop_iterations is called, so that final_giv_value will work correctly. */ - - for (bl = loop_iv_list; bl; bl = bl->next) - { - struct induction *v; - - for (v = bl->giv; v; v = v->next_iv) - if (! v->replaceable && ! v->not_replaceable) - check_final_value (v, loop_start, loop_end, loop_info->n_iterations); - } + loop_givs_check (loop); /* Try to prove that the loop counter variable (if any) is always nonnegative; if so, record that fact with a REG_NONNEG note so that "decrement and branch until zero" insn can be used. */ - check_dbra_loop (loop_end, insn_count, loop_start, loop_info); + check_dbra_loop (loop, insn_count); /* Create reg_map to hold substitutions for replaceable giv regs. Some givs might have been made from biv increments, so look at - reg_iv_type for a suitable size. */ - reg_map_size = reg_iv_type->num_elements; - reg_map = (rtx *) alloca (reg_map_size * sizeof (rtx)); - bzero ((char *) reg_map, reg_map_size * sizeof (rtx)); + ivs->reg_iv_type for a suitable size. */ + reg_map_size = ivs->n_regs; + reg_map = (rtx *) xcalloc (reg_map_size, sizeof (rtx)); /* Examine each iv class for feasibility of strength reduction/induction variable elimination. */ - for (bl = loop_iv_list; bl; bl = bl->next) + for (bl = ivs->list; bl; bl = bl->next) { struct induction *v; int benefit; - int all_reduced; - rtx final_value = 0; - unsigned nregs; /* Test whether it will be possible to eliminate this biv - provided all givs are reduced. This is possible if either - the reg is not used outside the loop, or we can compute - what its final value will be. - - For architectures with a decrement_and_branch_until_zero insn, - don't do this if we put a REG_NONNEG note on the endtest for - this biv. */ - - /* Compare against bl->init_insn rather than loop_start. - We aren't concerned with any uses of the biv between - init_insn and loop_start since these won't be affected - by the value of the biv elsewhere in the function, so - long as init_insn doesn't use the biv itself. - March 14, 1989 -- self@bayes.arc.nasa.gov */ - - if ((uid_luid[REGNO_LAST_UID (bl->regno)] < INSN_LUID (loop_end) - && bl->init_insn - && INSN_UID (bl->init_insn) < max_uid_for_loop - && uid_luid[REGNO_FIRST_UID (bl->regno)] >= INSN_LUID (bl->init_insn) -#ifdef HAVE_decrement_and_branch_until_zero - && ! bl->nonneg -#endif - && ! reg_mentioned_p (bl->biv->dest_reg, SET_SRC (bl->init_set))) - || ((final_value = final_biv_value (bl, loop_start, loop_end, - loop_info->n_iterations)) -#ifdef HAVE_decrement_and_branch_until_zero - && ! bl->nonneg -#endif - )) - bl->eliminable = maybe_eliminate_biv (bl, loop_start, end, 0, - threshold, insn_count); - else - { - if (loop_dump_stream) - { - fprintf (loop_dump_stream, - "Cannot eliminate biv %d.\n", - bl->regno); - fprintf (loop_dump_stream, - "First use: insn %d, last use: insn %d.\n", - REGNO_FIRST_UID (bl->regno), - REGNO_LAST_UID (bl->regno)); - } - } - - /* Combine all giv's for this iv_class. */ - combine_givs (bl); + provided all givs are reduced. */ + bl->eliminable = loop_biv_eliminable_p (loop, bl, threshold, insn_count); /* This will be true at the end, if all givs which depend on this biv have been strength reduced. We can't (currently) eliminate the biv unless this is so. */ - all_reduced = 1; + bl->all_reduced = 1; + + /* Check each extension dependent giv in this class to see if its + root biv is safe from wrapping in the interior mode. */ + check_ext_dependent_givs (bl, loop_info); + + /* Combine all giv's for this iv_class. */ + combine_givs (regs, bl); - /* Check each giv in this class to see if we will benefit by reducing - it. Skip giv's combined with others. */ for (v = bl->giv; v; v = v->next_iv) { struct induction *tv; @@ -4679,54 +5013,10 @@ strength_reduce (scan_start, end, loop_top, insn_count, if (v->ignore || v->same) continue; - benefit = v->benefit; - - /* Reduce benefit if not replaceable, since we will insert - a move-insn to replace the insn that calculates this giv. - Don't do this unless the giv is a user variable, since it - will often be marked non-replaceable because of the duplication - of the exit code outside the loop. In such a case, the copies - we insert are dead and will be deleted. So they don't have - a cost. Similar situations exist. */ - /* ??? The new final_[bg]iv_value code does a much better job - of finding replaceable giv's, and hence this code may no longer - be necessary. */ - if (! v->replaceable && ! bl->eliminable - && REG_USERVAR_P (v->dest_reg)) - benefit -= copy_cost; - - /* Decrease the benefit to count the add-insns that we will - insert to increment the reduced reg for the giv. */ - benefit -= add_cost * bl->biv_count; - - /* Decide whether to strength-reduce this giv or to leave the code - unchanged (recompute it from the biv each time it is used). - This decision can be made independently for each giv. */ - -#ifdef AUTO_INC_DEC - /* Attempt to guess whether autoincrement will handle some of the - new add insns; if so, increase BENEFIT (undo the subtraction of - add_cost that was done above). */ - if (v->giv_type == DEST_ADDR - && GET_CODE (v->mult_val) == CONST_INT) - { - if (HAVE_POST_INCREMENT - && INTVAL (v->mult_val) == GET_MODE_SIZE (v->mem_mode)) - benefit += add_cost * bl->biv_count; - else if (HAVE_PRE_INCREMENT - && INTVAL (v->mult_val) == GET_MODE_SIZE (v->mem_mode)) - benefit += add_cost * bl->biv_count; - else if (HAVE_POST_DECREMENT - && -INTVAL (v->mult_val) == GET_MODE_SIZE (v->mem_mode)) - benefit += add_cost * bl->biv_count; - else if (HAVE_PRE_DECREMENT - && -INTVAL (v->mult_val) == GET_MODE_SIZE (v->mem_mode)) - benefit += add_cost * bl->biv_count; - } -#endif + benefit = loop_giv_reduce_benefit (loop, bl, v, test_reg); /* If an insn is not to be strength reduced, then set its ignore - flag, and clear all_reduced. */ + flag, and clear bl->all_reduced. */ /* A giv that depends on a reversed biv must be reduced if it is used after the loop exit, otherwise, it would have the wrong @@ -4734,8 +5024,9 @@ strength_reduce (scan_start, end, loop_top, insn_count, of such giv's whether or not we know they are used after the loop exit. */ - if ( ! flag_reduce_all_givs && v->lifetime * threshold * benefit < insn_count - && ! bl->reversed ) + if (! flag_reduce_all_givs + && v->lifetime * threshold * benefit < insn_count + && ! bl->reversed) { if (loop_dump_stream) fprintf (loop_dump_stream, @@ -4743,7 +5034,7 @@ strength_reduce (scan_start, end, loop_top, insn_count, INSN_UID (v->insn), v->lifetime * threshold * benefit, insn_count); v->ignore = 1; - all_reduced = 0; + bl->all_reduced = 0; } else { @@ -4759,7 +5050,7 @@ strength_reduce (scan_start, end, loop_top, insn_count, "giv of insn %d: would need a multiply.\n", INSN_UID (v->insn)); v->ignore = 1; - all_reduced = 0; + bl->all_reduced = 0; break; } } @@ -4769,309 +5060,18 @@ strength_reduce (scan_start, end, loop_top, insn_count, last use is the definition of another giv. If so, it is likely dead and should not be used to derive another giv nor to eliminate a biv. */ - for (v = bl->giv; v; v = v->next_iv) - { - if (v->ignore - || (v->same && v->same->ignore)) - continue; - - if (v->last_use) - { - struct induction *v1; - - for (v1 = bl->giv; v1; v1 = v1->next_iv) - if (v->last_use == v1->insn) - v->maybe_dead = 1; - } - else if (v->giv_type == DEST_REG - && REGNO_FIRST_UID (REGNO (v->dest_reg)) == INSN_UID (v->insn)) - { - struct induction *v1; - - for (v1 = bl->giv; v1; v1 = v1->next_iv) - if (REGNO_LAST_UID (REGNO (v->dest_reg)) == INSN_UID (v1->insn)) - v->maybe_dead = 1; - } - } - - /* Now that we know which givs will be reduced, try to rearrange the - combinations to reduce register pressure. - recombine_givs calls find_life_end, which needs reg_iv_type and - reg_iv_info to be valid for all pseudos. We do the necessary - reallocation here since it allows to check if there are still - more bivs to process. */ - nregs = max_reg_num (); - if (nregs > reg_iv_type->num_elements) - { - /* If there are still more bivs to process, allocate some slack - space so that we're not constantly reallocating these arrays. */ - if (bl->next) - nregs += nregs / 4; - /* Reallocate reg_iv_type and reg_iv_info. */ - VARRAY_GROW (reg_iv_type, nregs); - VARRAY_GROW (reg_iv_info, nregs); - } -#if 0 - /* Disabled for the gcc-2.95 release. There are still some problems with - giv recombination. We have a patch from Joern which should fix those - problems. But the patch is fairly complex and not really suitable for - the gcc-2.95 branch at this stage. */ - recombine_givs (bl, loop_start, loop_end, unroll_p); -#endif + loop_givs_dead_check (loop, bl); /* Reduce each giv that we decided to reduce. */ - - for (v = bl->giv; v; v = v->next_iv) - { - struct induction *tv; - if (! v->ignore && v->same == 0) - { - int auto_inc_opt = 0; - - /* If the code for derived givs immediately below has already - allocated a new_reg, we must keep it. */ - if (! v->new_reg) - v->new_reg = gen_reg_rtx (v->mode); - - if (v->derived_from) - { - struct induction *d = v->derived_from; - - /* In case d->dest_reg is not replaceable, we have - to replace it in v->insn now. */ - if (! d->new_reg) - d->new_reg = gen_reg_rtx (d->mode); - PATTERN (v->insn) - = replace_rtx (PATTERN (v->insn), d->dest_reg, d->new_reg); - PATTERN (v->insn) - = replace_rtx (PATTERN (v->insn), v->dest_reg, v->new_reg); - if (bl->biv_count != 1) - { - /* For each place where the biv is incremented, add an - insn to set the new, reduced reg for the giv. */ - for (tv = bl->biv; tv; tv = tv->next_iv) - { - /* We always emit reduced giv increments before the - biv increment when bl->biv_count != 1. So by - emitting the add insns for derived givs after the - biv increment, they pick up the updated value of - the reduced giv. */ - emit_insn_after (copy_rtx (PATTERN (v->insn)), - tv->insn); - - } - } - continue; - } - -#ifdef AUTO_INC_DEC - /* If the target has auto-increment addressing modes, and - this is an address giv, then try to put the increment - immediately after its use, so that flow can create an - auto-increment addressing mode. */ - if (v->giv_type == DEST_ADDR && bl->biv_count == 1 - && bl->biv->always_executed && ! bl->biv->maybe_multiple - /* We don't handle reversed biv's because bl->biv->insn - does not have a valid INSN_LUID. */ - && ! bl->reversed - && v->always_executed && ! v->maybe_multiple - && INSN_UID (v->insn) < max_uid_for_loop) - { - /* If other giv's have been combined with this one, then - this will work only if all uses of the other giv's occur - before this giv's insn. This is difficult to check. - - We simplify this by looking for the common case where - there is one DEST_REG giv, and this giv's insn is the - last use of the dest_reg of that DEST_REG giv. If the - increment occurs after the address giv, then we can - perform the optimization. (Otherwise, the increment - would have to go before other_giv, and we would not be - able to combine it with the address giv to get an - auto-inc address.) */ - if (v->combined_with) - { - struct induction *other_giv = 0; - - for (tv = bl->giv; tv; tv = tv->next_iv) - if (tv->same == v) - { - if (other_giv) - break; - else - other_giv = tv; - } - if (! tv && other_giv - && REGNO (other_giv->dest_reg) < max_reg_before_loop - && (REGNO_LAST_UID (REGNO (other_giv->dest_reg)) - == INSN_UID (v->insn)) - && INSN_LUID (v->insn) < INSN_LUID (bl->biv->insn)) - auto_inc_opt = 1; - } - /* Check for case where increment is before the address - giv. Do this test in "loop order". */ - else if ((INSN_LUID (v->insn) > INSN_LUID (bl->biv->insn) - && (INSN_LUID (v->insn) < INSN_LUID (scan_start) - || (INSN_LUID (bl->biv->insn) - > INSN_LUID (scan_start)))) - || (INSN_LUID (v->insn) < INSN_LUID (scan_start) - && (INSN_LUID (scan_start) - < INSN_LUID (bl->biv->insn)))) - auto_inc_opt = -1; - else - auto_inc_opt = 1; - -#ifdef HAVE_cc0 - { - rtx prev; - - /* We can't put an insn immediately after one setting - cc0, or immediately before one using cc0. */ - if ((auto_inc_opt == 1 && sets_cc0_p (PATTERN (v->insn))) - || (auto_inc_opt == -1 - && (prev = prev_nonnote_insn (v->insn)) != 0 - && GET_RTX_CLASS (GET_CODE (prev)) == 'i' - && sets_cc0_p (PATTERN (prev)))) - auto_inc_opt = 0; - } -#endif - - if (auto_inc_opt) - v->auto_inc_opt = 1; - } -#endif - - /* For each place where the biv is incremented, add an insn - to increment the new, reduced reg for the giv. */ - for (tv = bl->biv; tv; tv = tv->next_iv) - { - rtx insert_before; - - if (! auto_inc_opt) - insert_before = tv->insn; - else if (auto_inc_opt == 1) - insert_before = NEXT_INSN (v->insn); - else - insert_before = v->insn; - - if (tv->mult_val == const1_rtx) - emit_iv_add_mult (tv->add_val, v->mult_val, - v->new_reg, v->new_reg, insert_before); - else /* tv->mult_val == const0_rtx */ - /* A multiply is acceptable here - since this is presumed to be seldom executed. */ - emit_iv_add_mult (tv->add_val, v->mult_val, - v->add_val, v->new_reg, insert_before); - } - - /* Add code at loop start to initialize giv's reduced reg. */ - - emit_iv_add_mult (bl->initial_value, v->mult_val, - v->add_val, v->new_reg, loop_start); - } - } + loop_givs_reduce (loop, bl); /* Rescan all givs. If a giv is the same as a giv not reduced, mark it as not reduced. - + For each giv register that can be reduced now: if replaceable, substitute reduced reg wherever the old giv occurs; else add new move insn "giv_reg = reduced_reg". */ - - for (v = bl->giv; v; v = v->next_iv) - { - if (v->same && v->same->ignore) - v->ignore = 1; - - if (v->ignore) - continue; - - /* Update expression if this was combined, in case other giv was - replaced. */ - if (v->same) - v->new_reg = replace_rtx (v->new_reg, - v->same->dest_reg, v->same->new_reg); - - if (v->giv_type == DEST_ADDR) - /* Store reduced reg as the address in the memref where we found - this giv. */ - validate_change (v->insn, v->location, v->new_reg, 0); - else if (v->replaceable) - { - reg_map[REGNO (v->dest_reg)] = v->new_reg; - -#if 0 - /* I can no longer duplicate the original problem. Perhaps - this is unnecessary now? */ - - /* Replaceable; it isn't strictly necessary to delete the old - insn and emit a new one, because v->dest_reg is now dead. - - However, especially when unrolling loops, the special - handling for (set REG0 REG1) in the second cse pass may - make v->dest_reg live again. To avoid this problem, emit - an insn to set the original giv reg from the reduced giv. - We can not delete the original insn, since it may be part - of a LIBCALL, and the code in flow that eliminates dead - libcalls will fail if it is deleted. */ - emit_insn_after (gen_move_insn (v->dest_reg, v->new_reg), - v->insn); -#endif - } - else - { - /* Not replaceable; emit an insn to set the original giv reg from - the reduced giv, same as above. */ - emit_insn_after (gen_move_insn (v->dest_reg, v->new_reg), - v->insn); - } - - /* When a loop is reversed, givs which depend on the reversed - biv, and which are live outside the loop, must be set to their - correct final value. This insn is only needed if the giv is - not replaceable. The correct final value is the same as the - value that the giv starts the reversed loop with. */ - if (bl->reversed && ! v->replaceable) - emit_iv_add_mult (bl->initial_value, v->mult_val, - v->add_val, v->dest_reg, end_insert_before); - else if (v->final_value) - { - rtx insert_before; - - /* If the loop has multiple exits, emit the insn before the - loop to ensure that it will always be executed no matter - how the loop exits. Otherwise, emit the insn after the loop, - since this is slightly more efficient. */ - if (loop_number_exit_count[uid_loop_num[INSN_UID (loop_start)]]) - insert_before = loop_start; - else - insert_before = end_insert_before; - emit_insn_before (gen_move_insn (v->dest_reg, v->final_value), - insert_before); - -#if 0 - /* If the insn to set the final value of the giv was emitted - before the loop, then we must delete the insn inside the loop - that sets it. If this is a LIBCALL, then we must delete - every insn in the libcall. Note, however, that - final_giv_value will only succeed when there are multiple - exits if the giv is dead at each exit, hence it does not - matter that the original insn remains because it is dead - anyways. */ - /* Delete the insn inside the loop that sets the giv since - the giv is now set before (or after) the loop. */ - delete_insn (v->insn); -#endif - } - - if (loop_dump_stream) - { - fprintf (loop_dump_stream, "giv at %d reduced to ", - INSN_UID (v->insn)); - print_rtl (loop_dump_stream, v->new_reg); - fprintf (loop_dump_stream, "\n"); - } - } + loop_givs_rescan (loop, bl, reg_map); /* All the givs based on the biv bl have been reduced if they merit it. */ @@ -5081,27 +5081,27 @@ strength_reduce (scan_start, end, loop_top, insn_count, v->new_reg will either be or refer to the register of the giv it combined with. - Doing this clearing avoids problems in biv elimination where a - giv's new_reg is a complex value that can't be put in the insn but - the giv combined with (with a reg as new_reg) is marked maybe_dead. - Since the register will be used in either case, we'd prefer it be - used from the simpler giv. */ + Doing this clearing avoids problems in biv elimination where + a giv's new_reg is a complex value that can't be put in the + insn but the giv combined with (with a reg as new_reg) is + marked maybe_dead. Since the register will be used in either + case, we'd prefer it be used from the simpler giv. */ for (v = bl->giv; v; v = v->next_iv) if (! v->maybe_dead && v->same) v->same->maybe_dead = 0; /* Try to eliminate the biv, if it is a candidate. - This won't work if ! all_reduced, + This won't work if ! bl->all_reduced, since the givs we planned to use might not have been reduced. - We have to be careful that we didn't initially think we could eliminate - this biv because of a giv that we now think may be dead and shouldn't - be used as a biv replacement. + We have to be careful that we didn't initially think we could + eliminate this biv because of a giv that we now think may be + dead and shouldn't be used as a biv replacement. Also, there is the possibility that we may have a giv that looks like it can be used to eliminate a biv, but the resulting insn - isn't valid. This can happen, for example, on the 88k, where a + isn't valid. This can happen, for example, on the 88k, where a JUMP_INSN can compare a register only with zero. Attempts to replace it with a compare with a constant will fail. @@ -5109,10 +5109,8 @@ strength_reduce (scan_start, end, loop_top, insn_count, of the occurrences of the biv with a giv, but no harm was done in doing so in the rare cases where it can occur. */ - if (all_reduced == 1 && bl->eliminable - && maybe_eliminate_biv (bl, loop_start, end, 1, - threshold, insn_count)) - + if (bl->all_reduced == 1 && bl->eliminable + && maybe_eliminate_biv (loop, bl, 1, threshold, insn_count)) { /* ?? If we created a new test to bypass the loop entirely, or otherwise drop straight in, based on this test, then @@ -5126,35 +5124,9 @@ strength_reduce (scan_start, end, loop_top, insn_count, Reversed bivs already have an insn after the loop setting their value, so we don't need another one. We can't calculate the proper final value for such a biv here anyways. */ - if (final_value != 0 && ! bl->reversed) - { - rtx insert_before; - - /* If the loop has multiple exits, emit the insn before the - loop to ensure that it will always be executed no matter - how the loop exits. Otherwise, emit the insn after the - loop, since this is slightly more efficient. */ - if (loop_number_exit_count[uid_loop_num[INSN_UID (loop_start)]]) - insert_before = loop_start; - else - insert_before = end_insert_before; - - emit_insn_before (gen_move_insn (bl->biv->dest_reg, final_value), - end_insert_before); - } - -#if 0 - /* Delete all of the instructions inside the loop which set - the biv, as they are all dead. If is safe to delete them, - because an insn setting a biv will never be part of a libcall. */ - /* However, deleting them will invalidate the regno_last_uid info, - so keeping them around is more convenient. Final_biv_value - will only succeed when there are multiple exits if the biv - is dead at each exit, hence it does not matter that the original - insn remains, because it is dead anyways. */ - for (v = bl->biv; v; v = v->next_iv) - delete_insn (v->insn); -#endif + if (bl->final_value && ! bl->reversed) + loop_insn_sink_or_swim (loop, gen_move_insn + (bl->biv->dest_reg, bl->final_value)); if (loop_dump_stream) fprintf (loop_dump_stream, "Reg %d: biv eliminated\n", @@ -5165,34 +5137,208 @@ strength_reduce (scan_start, end, loop_top, insn_count, /* Go through all the instructions in the loop, making all the register substitutions scheduled in REG_MAP. */ - for (p = loop_start; p != end; p = NEXT_INSN (p)) + for (p = loop->start; p != loop->end; p = NEXT_INSN (p)) if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN - || GET_CODE (p) == CALL_INSN) + || GET_CODE (p) == CALL_INSN) { replace_regs (PATTERN (p), reg_map, reg_map_size, 0); replace_regs (REG_NOTES (p), reg_map, reg_map_size, 0); INSN_CODE (p) = -1; } + if (loop_info->n_iterations > 0) + { + /* When we completely unroll a loop we will likely not need the increment + of the loop BIV and we will not need the conditional branch at the + end of the loop. */ + unrolled_insn_copies = insn_count - 2; + +#ifdef HAVE_cc0 + /* When we completely unroll a loop on a HAVE_cc0 machine we will not + need the comparison before the conditional branch at the end of the + loop. */ + unrolled_insn_copies -= 1; +#endif + + /* We'll need one copy for each loop iteration. */ + unrolled_insn_copies *= loop_info->n_iterations; + + /* A little slop to account for the ability to remove initialization + code, better CSE, and other secondary benefits of completely + unrolling some loops. */ + unrolled_insn_copies -= 1; + + /* Clamp the value. */ + if (unrolled_insn_copies < 0) + unrolled_insn_copies = 0; + } + /* Unroll loops from within strength reduction so that we can use the induction variable information that strength_reduce has already - collected. */ - - if (unroll_p) - unroll_loop (loop_end, insn_count, loop_start, end_insert_before, - loop_info, 1); - -#ifdef HAVE_decrement_and_branch_on_count - /* Instrument the loop with BCT insn. */ - if (HAVE_decrement_and_branch_on_count && bct_p - && flag_branch_on_count_reg) - insert_bct (loop_start, loop_end, loop_info); -#endif /* HAVE_decrement_and_branch_on_count */ + collected. Always unroll loops that would be as small or smaller + unrolled than when rolled. */ + if ((flags & LOOP_UNROLL) + || (loop_info->n_iterations > 0 + && unrolled_insn_copies <= insn_count)) + unroll_loop (loop, insn_count, 1); + +#ifdef HAVE_doloop_end + if (HAVE_doloop_end && (flags & LOOP_BCT) && flag_branch_on_count_reg) + doloop_optimize (loop); +#endif /* HAVE_doloop_end */ + + /* In case number of iterations is known, drop branch prediction note + in the branch. Do that only in second loop pass, as loop unrolling + may change the number of iterations performed. */ + if ((flags & LOOP_BCT) + && loop_info->n_iterations / loop_info->unroll_number > 1) + { + int n = loop_info->n_iterations / loop_info->unroll_number; + predict_insn (PREV_INSN (loop->end), + PRED_LOOP_ITERATIONS, + REG_BR_PROB_BASE - REG_BR_PROB_BASE / n); + } if (loop_dump_stream) fprintf (loop_dump_stream, "\n"); - VARRAY_FREE (reg_iv_type); - VARRAY_FREE (reg_iv_info); + + loop_ivs_free (loop); + if (reg_map) + free (reg_map); +} + +/*Record all basic induction variables calculated in the insn. */ +static rtx +check_insn_for_bivs (loop, p, not_every_iteration, maybe_multiple) + struct loop *loop; + rtx p; + int not_every_iteration; + int maybe_multiple; +{ + struct loop_ivs *ivs = LOOP_IVS (loop); + rtx set; + rtx dest_reg; + rtx inc_val; + rtx mult_val; + rtx *location; + + if (GET_CODE (p) == INSN + && (set = single_set (p)) + && GET_CODE (SET_DEST (set)) == REG) + { + dest_reg = SET_DEST (set); + if (REGNO (dest_reg) < max_reg_before_loop + && REGNO (dest_reg) >= FIRST_PSEUDO_REGISTER + && REG_IV_TYPE (ivs, REGNO (dest_reg)) != NOT_BASIC_INDUCT) + { + if (basic_induction_var (loop, SET_SRC (set), + GET_MODE (SET_SRC (set)), + dest_reg, p, &inc_val, &mult_val, + &location)) + { + /* It is a possible basic induction variable. + Create and initialize an induction structure for it. */ + + struct induction *v + = (struct induction *) xmalloc (sizeof (struct induction)); + + record_biv (loop, v, p, dest_reg, inc_val, mult_val, location, + not_every_iteration, maybe_multiple); + REG_IV_TYPE (ivs, REGNO (dest_reg)) = BASIC_INDUCT; + } + else if (REGNO (dest_reg) < ivs->n_regs) + REG_IV_TYPE (ivs, REGNO (dest_reg)) = NOT_BASIC_INDUCT; + } + } + return p; +} + +/* Record all givs calculated in the insn. + A register is a giv if: it is only set once, it is a function of a + biv and a constant (or invariant), and it is not a biv. */ +static rtx +check_insn_for_givs (loop, p, not_every_iteration, maybe_multiple) + struct loop *loop; + rtx p; + int not_every_iteration; + int maybe_multiple; +{ + struct loop_regs *regs = LOOP_REGS (loop); + + rtx set; + /* Look for a general induction variable in a register. */ + if (GET_CODE (p) == INSN + && (set = single_set (p)) + && GET_CODE (SET_DEST (set)) == REG + && ! regs->array[REGNO (SET_DEST (set))].may_not_optimize) + { + rtx src_reg; + rtx dest_reg; + rtx add_val; + rtx mult_val; + rtx ext_val; + int benefit; + rtx regnote = 0; + rtx last_consec_insn; + + dest_reg = SET_DEST (set); + if (REGNO (dest_reg) < FIRST_PSEUDO_REGISTER) + return p; + + if (/* SET_SRC is a giv. */ + (general_induction_var (loop, SET_SRC (set), &src_reg, &add_val, + &mult_val, &ext_val, 0, &benefit, VOIDmode) + /* Equivalent expression is a giv. */ + || ((regnote = find_reg_note (p, REG_EQUAL, NULL_RTX)) + && general_induction_var (loop, XEXP (regnote, 0), &src_reg, + &add_val, &mult_val, &ext_val, 0, + &benefit, VOIDmode))) + /* Don't try to handle any regs made by loop optimization. + We have nothing on them in regno_first_uid, etc. */ + && REGNO (dest_reg) < max_reg_before_loop + /* Don't recognize a BASIC_INDUCT_VAR here. */ + && dest_reg != src_reg + /* This must be the only place where the register is set. */ + && (regs->array[REGNO (dest_reg)].n_times_set == 1 + /* or all sets must be consecutive and make a giv. */ + || (benefit = consec_sets_giv (loop, benefit, p, + src_reg, dest_reg, + &add_val, &mult_val, &ext_val, + &last_consec_insn)))) + { + struct induction *v + = (struct induction *) xmalloc (sizeof (struct induction)); + + /* If this is a library call, increase benefit. */ + if (find_reg_note (p, REG_RETVAL, NULL_RTX)) + benefit += libcall_benefit (p); + + /* Skip the consecutive insns, if there are any. */ + if (regs->array[REGNO (dest_reg)].n_times_set != 1) + p = last_consec_insn; + + record_giv (loop, v, p, src_reg, dest_reg, mult_val, add_val, + ext_val, benefit, DEST_REG, not_every_iteration, + maybe_multiple, (rtx*) 0); + + } + } + +#ifndef DONT_REDUCE_ADDR + /* Look for givs which are memory addresses. */ + /* This resulted in worse code on a VAX 8600. I wonder if it + still does. */ + if (GET_CODE (p) == INSN) + find_mem_givs (loop, PATTERN (p), p, not_every_iteration, + maybe_multiple); +#endif + + /* Update the status of whether giv can derive other givs. This can + change when we pass a label or an insn that updates a biv. */ + if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN + || GET_CODE (p) == CODE_LABEL) + update_giv_derive (loop, p); + return p; } /* Return 1 if X is a valid source for an initial value (or as value being @@ -5237,18 +5383,19 @@ valid_initial_value_p (x, insn, call_seen, loop_start) /* Scan X for memory refs and check each memory address as a possible giv. INSN is the insn whose pattern X comes from. NOT_EVERY_ITERATION is 1 if the insn might not be executed during - every loop iteration. */ + every loop iteration. MAYBE_MULTIPLE is 1 if the insn might be executed + more thanonce in each loop iteration. */ static void -find_mem_givs (x, insn, not_every_iteration, loop_start, loop_end) +find_mem_givs (loop, x, insn, not_every_iteration, maybe_multiple) + const struct loop *loop; rtx x; rtx insn; - int not_every_iteration; - rtx loop_start, loop_end; + int not_every_iteration, maybe_multiple; { - register int i, j; - register enum rtx_code code; - register char *fmt; + int i, j; + enum rtx_code code; + const char *fmt; if (x == 0) return; @@ -5275,25 +5422,27 @@ find_mem_givs (x, insn, not_every_iteration, loop_start, loop_end) rtx src_reg; rtx add_val; rtx mult_val; + rtx ext_val; int benefit; /* This code used to disable creating GIVs with mult_val == 1 and - add_val == 0. However, this leads to lost optimizations when + add_val == 0. However, this leads to lost optimizations when it comes time to combine a set of related DEST_ADDR GIVs, since - this one would not be seen. */ + this one would not be seen. */ - if (general_induction_var (XEXP (x, 0), &src_reg, &add_val, - &mult_val, 1, &benefit)) + if (general_induction_var (loop, XEXP (x, 0), &src_reg, &add_val, + &mult_val, &ext_val, 1, &benefit, + GET_MODE (x))) { /* Found one; record it. */ struct induction *v - = (struct induction *) oballoc (sizeof (struct induction)); + = (struct induction *) xmalloc (sizeof (struct induction)); - record_giv (v, insn, src_reg, addr_placeholder, mult_val, - add_val, benefit, DEST_ADDR, not_every_iteration, - &XEXP (x, 0), loop_start, loop_end); + record_giv (loop, v, insn, src_reg, addr_placeholder, mult_val, + add_val, ext_val, benefit, DEST_ADDR, + not_every_iteration, maybe_multiple, &XEXP (x, 0)); - v->mem_mode = GET_MODE (x); + v->mem = x; } } return; @@ -5307,12 +5456,12 @@ find_mem_givs (x, insn, not_every_iteration, loop_start, loop_end) fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) if (fmt[i] == 'e') - find_mem_givs (XEXP (x, i), insn, not_every_iteration, loop_start, - loop_end); + find_mem_givs (loop, XEXP (x, i), insn, not_every_iteration, + maybe_multiple); else if (fmt[i] == 'E') for (j = 0; j < XVECLEN (x, i); j++) - find_mem_givs (XVECEXP (x, i, j), insn, not_every_iteration, - loop_start, loop_end); + find_mem_givs (loop, XVECEXP (x, i, j), insn, not_every_iteration, + maybe_multiple); } /* Fill in the data about one biv update. @@ -5332,8 +5481,9 @@ find_mem_givs (x, insn, not_every_iteration, loop_start, loop_end) executed exactly once per iteration. */ static void -record_biv (v, insn, dest_reg, inc_val, mult_val, location, +record_biv (loop, v, insn, dest_reg, inc_val, mult_val, location, not_every_iteration, maybe_multiple) + struct loop *loop; struct induction *v; rtx insn; rtx dest_reg; @@ -5343,6 +5493,7 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, int not_every_iteration; int maybe_multiple; { + struct loop_ivs *ivs = LOOP_IVS (loop); struct iv_class *bl; v->insn = insn; @@ -5350,6 +5501,7 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, v->dest_reg = dest_reg; v->mult_val = mult_val; v->add_val = inc_val; + v->ext_dependent = NULL_RTX; v->location = location; v->mode = GET_MODE (dest_reg); v->always_computable = ! not_every_iteration; @@ -5359,12 +5511,12 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, /* Add this to the reg's iv_class, creating a class if this is the first incrementation of the reg. */ - bl = reg_biv_class[REGNO (dest_reg)]; + bl = REG_IV_CLASS (ivs, REGNO (dest_reg)); if (bl == 0) { /* Create and initialize new iv_class. */ - bl = (struct iv_class *) oballoc (sizeof (struct iv_class)); + bl = (struct iv_class *) xmalloc (sizeof (struct iv_class)); bl->regno = REGNO (dest_reg); bl->biv = 0; @@ -5374,6 +5526,7 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, /* Set initial value to the reg itself. */ bl->initial_value = dest_reg; + bl->final_value = 0; /* We haven't seen the initializing insn yet */ bl->init_insn = 0; bl->init_set = 0; @@ -5384,12 +5537,12 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, bl->reversed = 0; bl->total_benefit = 0; - /* Add this class to loop_iv_list. */ - bl->next = loop_iv_list; - loop_iv_list = bl; + /* Add this class to ivs->list. */ + bl->next = ivs->list; + ivs->list = bl; /* Put it in the array of biv register classes. */ - reg_biv_class[REGNO (dest_reg)] = bl; + REG_IV_CLASS (ivs, REGNO (dest_reg)) = bl; } /* Update IV_CLASS entry for this biv. */ @@ -5400,23 +5553,7 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, bl->incremented = 1; if (loop_dump_stream) - { - fprintf (loop_dump_stream, - "Insn %d: possible biv, reg %d,", - INSN_UID (insn), REGNO (dest_reg)); - if (GET_CODE (inc_val) == CONST_INT) - { - fprintf (loop_dump_stream, " const ="); - fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, INTVAL (inc_val)); - fputc ('\n', loop_dump_stream); - } - else - { - fprintf (loop_dump_stream, " const = "); - print_rtl (loop_dump_stream, inc_val); - fprintf (loop_dump_stream, "\n"); - } - } + loop_biv_dump (v, loop_dump_stream, 0); } /* Fill in the data about one giv. @@ -5433,22 +5570,32 @@ record_biv (v, insn, dest_reg, inc_val, mult_val, location, LOCATION points to the place where this giv's value appears in INSN. */ static void -record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, - type, not_every_iteration, location, loop_start, loop_end) +record_giv (loop, v, insn, src_reg, dest_reg, mult_val, add_val, ext_val, + benefit, type, not_every_iteration, maybe_multiple, location) + const struct loop *loop; struct induction *v; rtx insn; rtx src_reg; rtx dest_reg; - rtx mult_val, add_val; + rtx mult_val, add_val, ext_val; int benefit; enum g_types type; - int not_every_iteration; + int not_every_iteration, maybe_multiple; rtx *location; - rtx loop_start, loop_end; { + struct loop_ivs *ivs = LOOP_IVS (loop); struct induction *b; struct iv_class *bl; rtx set = single_set (insn); + rtx temp; + + /* Attempt to prove constantness of the values. Don't let simplity_rtx + undo the MULT canonicalization that we performed earlier. */ + temp = simplify_rtx (add_val); + if (temp + && ! (GET_CODE (add_val) == MULT + && GET_CODE (temp) == ASHIFT)) + add_val = temp; v->insn = insn; v->src_reg = src_reg; @@ -5456,11 +5603,12 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, v->dest_reg = dest_reg; v->mult_val = mult_val; v->add_val = add_val; + v->ext_dependent = ext_val; v->benefit = benefit; v->location = location; v->cant_derive = 0; v->combined_with = 0; - v->maybe_multiple = 0; + v->maybe_multiple = maybe_multiple; v->maybe_dead = 0; v->derive_adjustment = 0; v->same = 0; @@ -5471,8 +5619,6 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, v->auto_inc_opt = 0; v->unrolled = 0; v->shared = 0; - v->derived_from = 0; - v->last_use = 0; /* The v->always_computable field is used in update_giv_derive, to determine whether a giv can be used to derive another giv. For a @@ -5498,8 +5644,7 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, { v->mode = GET_MODE (SET_DEST (set)); - v->lifetime = (uid_luid[REGNO_LAST_UID (REGNO (dest_reg))] - - uid_luid[REGNO_FIRST_UID (REGNO (dest_reg))]); + v->lifetime = LOOP_REG_LIFETIME (loop, REGNO (dest_reg)); /* If the lifetime is zero, it means that this register is really a dead store. So mark this as a giv that can be @@ -5507,13 +5652,13 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, if (v->lifetime == 0) v->ignore = 1; - REG_IV_TYPE (REGNO (dest_reg)) = GENERAL_INDUCT; - REG_IV_INFO (REGNO (dest_reg)) = v; + REG_IV_TYPE (ivs, REGNO (dest_reg)) = GENERAL_INDUCT; + REG_IV_INFO (ivs, REGNO (dest_reg)) = v; } /* Add the giv to the class of givs computed from one biv. */ - bl = reg_biv_class[REGNO (src_reg)]; + bl = REG_IV_CLASS (ivs, REGNO (src_reg)); if (bl) { v->next_iv = bl->giv; @@ -5534,26 +5679,27 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, { /* The giv can be replaced outright by the reduced register only if all of the following conditions are true: - - the insn that sets the giv is always executed on any iteration + - the insn that sets the giv is always executed on any iteration on which the giv is used at all (there are two ways to deduce this: either the insn is executed on every iteration, or all uses follow that insn in the same basic block), - - the giv is not used outside the loop + - the giv is not used outside the loop - no assignments to the biv occur during the giv's lifetime. */ if (REGNO_FIRST_UID (REGNO (dest_reg)) == INSN_UID (insn) /* Previous line always fails if INSN was moved by loop opt. */ - && uid_luid[REGNO_LAST_UID (REGNO (dest_reg))] < INSN_LUID (loop_end) + && REGNO_LAST_LUID (REGNO (dest_reg)) + < INSN_LUID (loop->end) && (! not_every_iteration || last_use_this_basic_block (dest_reg, insn))) - { + { /* Now check that there are no assignments to the biv within the giv's lifetime. This requires two separate checks. */ /* Check each biv update, and fail if any are between the first and last use of the giv. - + If this loop contains an inner loop that was unrolled, then the insn modifying the biv may have been emitted by the loop unrolling code, and hence does not have a valid luid. Just @@ -5566,22 +5712,22 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, for (b = bl->biv; b; b = b->next_iv) { if (INSN_UID (b->insn) >= max_uid_for_loop - || ((uid_luid[INSN_UID (b->insn)] - >= uid_luid[REGNO_FIRST_UID (REGNO (dest_reg))]) - && (uid_luid[INSN_UID (b->insn)] - <= uid_luid[REGNO_LAST_UID (REGNO (dest_reg))]))) + || ((INSN_LUID (b->insn) + >= REGNO_FIRST_LUID (REGNO (dest_reg))) + && (INSN_LUID (b->insn) + <= REGNO_LAST_LUID (REGNO (dest_reg))))) { v->replaceable = 0; v->not_replaceable = 1; break; - } + } } /* If there are any backwards branches that go from after the biv update to before it, then this giv is not replaceable. */ if (v->replaceable) for (b = bl->biv; b; b = b->next_iv) - if (back_branch_in_range_p (b->insn, loop_start, loop_end)) + if (back_branch_in_range_p (loop, b->insn)) { v->replaceable = 0; v->not_replaceable = 1; @@ -5605,11 +5751,11 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, v->no_const_addval = 1; if (tem == const0_rtx) ; - else if (GET_CODE (tem) == CONST_INT) + else if (CONSTANT_P (add_val)) v->no_const_addval = 0; - else if (GET_CODE (tem) == PLUS) + if (GET_CODE (tem) == PLUS) { - while (1) + while (1) { if (GET_CODE (XEXP (tem, 0)) == PLUS) tem = XEXP (tem, 0); @@ -5618,60 +5764,15 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, else break; } - if (GET_CODE (XEXP (tem, 1)) == CONST_INT) - v->no_const_addval = 0; + if (CONSTANT_P (XEXP (tem, 1))) + v->no_const_addval = 0; } } if (loop_dump_stream) - { - if (type == DEST_REG) - fprintf (loop_dump_stream, "Insn %d: giv reg %d", - INSN_UID (insn), REGNO (dest_reg)); - else - fprintf (loop_dump_stream, "Insn %d: dest address", - INSN_UID (insn)); - - fprintf (loop_dump_stream, " src reg %d benefit %d", - REGNO (src_reg), v->benefit); - fprintf (loop_dump_stream, " lifetime %d", - v->lifetime); - - if (v->replaceable) - fprintf (loop_dump_stream, " replaceable"); - - if (v->no_const_addval) - fprintf (loop_dump_stream, " ncav"); - - if (GET_CODE (mult_val) == CONST_INT) - { - fprintf (loop_dump_stream, " mult "); - fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, INTVAL (mult_val)); - } - else - { - fprintf (loop_dump_stream, " mult "); - print_rtl (loop_dump_stream, mult_val); - } - - if (GET_CODE (add_val) == CONST_INT) - { - fprintf (loop_dump_stream, " add "); - fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, INTVAL (add_val)); - } - else - { - fprintf (loop_dump_stream, " add "); - print_rtl (loop_dump_stream, add_val); - } - } - - if (loop_dump_stream) - fprintf (loop_dump_stream, "\n"); - + loop_giv_dump (v, loop_dump_stream, 0); } - /* All this does is determine whether a giv can be made replaceable because its final value can be calculated. This code can not be part of record_giv above, because final_giv_value requires that the number of loop iterations @@ -5679,15 +5780,15 @@ record_giv (v, insn, src_reg, dest_reg, mult_val, add_val, benefit, have been identified. */ static void -check_final_value (v, loop_start, loop_end, n_iterations) +check_final_value (loop, v) + const struct loop *loop; struct induction *v; - rtx loop_start, loop_end; - unsigned HOST_WIDE_INT n_iterations; { + struct loop_ivs *ivs = LOOP_IVS (loop); struct iv_class *bl; rtx final_value = 0; - bl = reg_biv_class[REGNO (v->src_reg)]; + bl = REG_IV_CLASS (ivs, REGNO (v->src_reg)); /* DEST_ADDR givs will never reach here, because they are always marked replaceable above in record_giv. */ @@ -5701,7 +5802,7 @@ check_final_value (v, loop_start, loop_end, n_iterations) or all uses follow that insn in the same basic block), - its final value can be calculated (this condition is different than the one above in record_giv) - - it's not used before it's set + - it's not used before the it's set - no assignments to the biv occur during the giv's lifetime. */ #if 0 @@ -5710,7 +5811,7 @@ check_final_value (v, loop_start, loop_end, n_iterations) v->replaceable = 0; #endif - if ((final_value = final_giv_value (v, loop_start, loop_end, n_iterations)) + if ((final_value = final_giv_value (loop, v)) && (v->always_computable || last_use_this_basic_block (v->dest_reg, v->insn))) { int biv_increment_seen = 0, before_giv_insn = 0; @@ -5742,10 +5843,10 @@ check_final_value (v, loop_start, loop_end, n_iterations) while (1) { p = NEXT_INSN (p); - if (p == loop_end) + if (p == loop->end) { before_giv_insn = 1; - p = NEXT_INSN (loop_start); + p = NEXT_INSN (loop->start); } if (p == v->insn) break; @@ -5774,7 +5875,7 @@ check_final_value (v, loop_start, loop_end, n_iterations) } } } - + /* Now that the lifetime of the giv is known, check for branches from within the lifetime to outside the lifetime if it is still replaceable. */ @@ -5785,17 +5886,17 @@ check_final_value (v, loop_start, loop_end, n_iterations) while (1) { p = NEXT_INSN (p); - if (p == loop_end) - p = NEXT_INSN (loop_start); + if (p == loop->end) + p = NEXT_INSN (loop->start); if (p == last_giv_use) break; if (GET_CODE (p) == JUMP_INSN && JUMP_LABEL (p) && LABEL_NAME (JUMP_LABEL (p)) && ((loop_insn_first_p (JUMP_LABEL (p), v->insn) - && loop_insn_first_p (loop_start, JUMP_LABEL (p))) + && loop_insn_first_p (loop->start, JUMP_LABEL (p))) || (loop_insn_first_p (last_giv_use, JUMP_LABEL (p)) - && loop_insn_first_p (JUMP_LABEL (p), loop_end)))) + && loop_insn_first_p (JUMP_LABEL (p), loop->end)))) { v->replaceable = 0; v->not_replaceable = 1; @@ -5831,9 +5932,11 @@ check_final_value (v, loop_start, loop_end, n_iterations) The cases we look at are when a label or an update to a biv is passed. */ static void -update_giv_derive (p) +update_giv_derive (loop, p) + const struct loop *loop; rtx p; { + struct loop_ivs *ivs = LOOP_IVS (loop); struct iv_class *bl; struct induction *biv, *giv; rtx tem; @@ -5866,7 +5969,7 @@ update_giv_derive (p) subsequent biv update was performed. If this adjustment cannot be done, the giv cannot derive further givs. */ - for (bl = loop_iv_list; bl; bl = bl->next) + for (bl = ivs->list; bl; bl = bl->next) for (biv = bl->biv; biv; biv = biv->next_iv) if (GET_CODE (p) == CODE_LABEL || GET_CODE (p) == JUMP_INSN || biv->insn == p) @@ -5896,18 +5999,22 @@ update_giv_derive (p) be able to compute a compensation. */ else if (biv->insn == p) { - tem = 0; + rtx ext_val_dummy; + tem = 0; if (biv->mult_val == const1_rtx) - tem = simplify_giv_expr (gen_rtx_MULT (giv->mode, + tem = simplify_giv_expr (loop, + gen_rtx_MULT (giv->mode, biv->add_val, giv->mult_val), - &dummy); + &ext_val_dummy, &dummy); if (tem && giv->derive_adjustment) - tem = simplify_giv_expr (gen_rtx_PLUS (giv->mode, tem, - giv->derive_adjustment), - &dummy); + tem = simplify_giv_expr + (loop, + gen_rtx_PLUS (giv->mode, tem, giv->derive_adjustment), + &ext_val_dummy, &dummy); + if (tem) giv->derive_adjustment = tem; else @@ -5950,7 +6057,7 @@ update_giv_derive (p) Note that treating the entire pseudo as a BIV will result in making simple increments to any GIVs based on it. However, if the variable overflows in its declared mode but not its promoted mode, the result will - be incorrect. This is acceptable if the variable is signed, since + be incorrect. This is acceptable if the variable is signed, since overflows in such cases are undefined, but not if it is unsigned, since those overflows are defined. So we only check for SIGN_EXTEND and not ZERO_EXTEND. @@ -5958,20 +6065,22 @@ update_giv_derive (p) If we cannot find a biv, we return 0. */ static int -basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) - register rtx x; +basic_induction_var (loop, x, mode, dest_reg, p, inc_val, mult_val, location) + const struct loop *loop; + rtx x; enum machine_mode mode; - rtx p; rtx dest_reg; + rtx p; rtx *inc_val; rtx *mult_val; rtx **location; { - register enum rtx_code code; + enum rtx_code code; rtx *argp, arg; rtx insn, set = 0; code = GET_CODE (x); + *location = NULL; switch (code) { case PLUS: @@ -5990,10 +6099,10 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) argp = &XEXP (x, 0); } else - return 0; + return 0; arg = *argp; - if (invariant_p (arg) != 1) + if (loop_invariant_p (loop, arg) != 1) return 0; *inc_val = convert_modes (GET_MODE (dest_reg), GET_MODE (x), arg, 0); @@ -6005,7 +6114,8 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) /* If this is a SUBREG for a promoted variable, check the inner value. */ if (SUBREG_PROMOTED_VAR_P (x)) - return basic_induction_var (SUBREG_REG (x), GET_MODE (SUBREG_REG (x)), + return basic_induction_var (loop, SUBREG_REG (x), + GET_MODE (SUBREG_REG (x)), dest_reg, p, inc_val, mult_val, location); return 0; @@ -6013,28 +6123,34 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) /* If this register is assigned in a previous insn, look at its source, but don't go outside the loop or past a label. */ + /* If this sets a register to itself, we would repeat any previous + biv increment if we applied this strategy blindly. */ + if (rtx_equal_p (dest_reg, x)) + return 0; + insn = p; while (1) { rtx dest; - do { - insn = PREV_INSN (insn); - } while (insn && GET_CODE (insn) == NOTE - && NOTE_LINE_NUMBER (insn) != NOTE_INSN_LOOP_BEG); + do + { + insn = PREV_INSN (insn); + } + while (insn && GET_CODE (insn) == NOTE + && NOTE_LINE_NUMBER (insn) != NOTE_INSN_LOOP_BEG); - if (!insn) + if (!insn) break; set = single_set (insn); if (set == 0) break; - dest = SET_DEST (set); if (dest == x || (GET_CODE (dest) == SUBREG && (GET_MODE_SIZE (GET_MODE (dest)) <= UNITS_PER_WORD) && (GET_MODE_CLASS (GET_MODE (dest)) == MODE_INT) && SUBREG_REG (dest) == x)) - return basic_induction_var (SET_SRC (set), + return basic_induction_var (loop, SET_SRC (set), (GET_MODE (SET_SRC (set)) == VOIDmode ? GET_MODE (x) : GET_MODE (SET_SRC (set))), @@ -6049,14 +6165,14 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) if (dest == x) break; } - /* ... fall through ... */ + /* Fall through. */ /* Can accept constant setting of biv only when inside inner most loop. - Otherwise, a biv of an inner loop may be incorrectly recognized + Otherwise, a biv of an inner loop may be incorrectly recognized as a biv of the outer loop, causing code to be moved INTO the inner loop. */ case MEM: - if (invariant_p (x) != 1) + if (loop_invariant_p (loop, x) != 1) return 0; case CONST_INT: case SYMBOL_REF: @@ -6064,20 +6180,20 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) /* convert_modes aborts if we try to convert to or from CCmode, so just exclude that case. It is very unlikely that a condition code value would be a useful iterator anyways. */ - if (loops_enclosed == 1 + if (loop->level == 1 && GET_MODE_CLASS (mode) != MODE_CC && GET_MODE_CLASS (GET_MODE (dest_reg)) != MODE_CC) - { + { /* Possible bug here? Perhaps we don't know the mode of X. */ *inc_val = convert_modes (GET_MODE (dest_reg), mode, x, 0); - *mult_val = const0_rtx; - return 1; - } + *mult_val = const0_rtx; + return 1; + } else - return 0; + return 0; case SIGN_EXTEND: - return basic_induction_var (XEXP (x, 0), GET_MODE (XEXP (x, 0)), + return basic_induction_var (loop, XEXP (x, 0), GET_MODE (XEXP (x, 0)), dest_reg, p, inc_val, mult_val, location); case ASHIFTRT: @@ -6091,12 +6207,13 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) if (insn) set = single_set (insn); - if (set && SET_DEST (set) == XEXP (x, 0) + if (! rtx_equal_p (dest_reg, XEXP (x, 0)) + && set && SET_DEST (set) == XEXP (x, 0) && GET_CODE (XEXP (x, 1)) == CONST_INT && INTVAL (XEXP (x, 1)) >= 0 && GET_CODE (SET_SRC (set)) == ASHIFT && XEXP (x, 1) == XEXP (SET_SRC (set), 1)) - return basic_induction_var (XEXP (SET_SRC (set), 0), + return basic_induction_var (loop, XEXP (SET_SRC (set), 0), GET_MODE (XEXP (x, 0)), dest_reg, insn, inc_val, mult_val, location); @@ -6122,31 +6239,30 @@ basic_induction_var (x, mode, dest_reg, p, inc_val, mult_val, location) such that the value of X is biv * mult + add; */ static int -general_induction_var (x, src_reg, add_val, mult_val, is_addr, pbenefit) +general_induction_var (loop, x, src_reg, add_val, mult_val, ext_val, + is_addr, pbenefit, addr_mode) + const struct loop *loop; rtx x; rtx *src_reg; rtx *add_val; rtx *mult_val; + rtx *ext_val; int is_addr; int *pbenefit; + enum machine_mode addr_mode; { + struct loop_ivs *ivs = LOOP_IVS (loop); rtx orig_x = x; - char *storage; /* If this is an invariant, forget it, it isn't a giv. */ - if (invariant_p (x) == 1) + if (loop_invariant_p (loop, x) == 1) return 0; - /* See if the expression could be a giv and get its form. - Mark our place on the obstack in case we don't find a giv. */ - storage = (char *) oballoc (0); *pbenefit = 0; - x = simplify_giv_expr (x, pbenefit); + *ext_val = NULL_RTX; + x = simplify_giv_expr (loop, x, ext_val, pbenefit); if (x == 0) - { - obfree (storage); - return 0; - } + return 0; switch (GET_CODE (x)) { @@ -6155,7 +6271,7 @@ general_induction_var (x, src_reg, add_val, mult_val, is_addr, pbenefit) /* Since this is now an invariant and wasn't before, it must be a giv with MULT_VAL == 0. It doesn't matter which BIV we associate this with. */ - *src_reg = loop_iv_list->biv->dest_reg; + *src_reg = ivs->list->biv->dest_reg; *mult_val = const0_rtx; *add_val = x; break; @@ -6202,25 +6318,19 @@ general_induction_var (x, src_reg, add_val, mult_val, is_addr, pbenefit) *mult_val = XEXP (*mult_val, 0); if (is_addr) - { -#ifdef ADDRESS_COST - *pbenefit += ADDRESS_COST (orig_x) - reg_address_cost; -#else - *pbenefit += rtx_cost (orig_x, MEM) - reg_address_cost; -#endif - } + *pbenefit += address_cost (orig_x, addr_mode) - reg_address_cost; else *pbenefit += rtx_cost (orig_x, SET); /* Always return true if this is a giv so it will be detected as such, - even if the benefit is zero or negative. This allows elimination - of bivs that might otherwise not be eliminated. */ - return 1; + even if the benefit is zero or negative. This allows elimination + of bivs that might otherwise not be eliminated. */ + return 1; } /* Given an expression, X, try to form it as a linear function of a biv. We will canonicalize it to be of the form - (plus (mult (BIV) (invar_1)) + (plus (mult (BIV) (invar_1)) (invar_2)) with possible degeneracies. @@ -6234,18 +6344,22 @@ general_induction_var (x, src_reg, add_val, mult_val, is_addr, pbenefit) returns 0. For a non-zero return, the result will have a code of CONST_INT, USE, - REG (for a BIV), PLUS, or MULT. No other codes will occur. + REG (for a BIV), PLUS, or MULT. No other codes will occur. *BENEFIT will be incremented by the benefit of any sub-giv encountered. */ -static rtx sge_plus PROTO ((enum machine_mode, rtx, rtx)); -static rtx sge_plus_constant PROTO ((rtx, rtx)); +static rtx sge_plus PARAMS ((enum machine_mode, rtx, rtx)); +static rtx sge_plus_constant PARAMS ((rtx, rtx)); static rtx -simplify_giv_expr (x, benefit) +simplify_giv_expr (loop, x, ext_val, benefit) + const struct loop *loop; rtx x; + rtx *ext_val; int *benefit; { + struct loop_ivs *ivs = LOOP_IVS (loop); + struct loop_regs *regs = LOOP_REGS (loop); enum machine_mode mode = GET_MODE (x); rtx arg0, arg1; rtx tem; @@ -6260,8 +6374,8 @@ simplify_giv_expr (x, benefit) switch (GET_CODE (x)) { case PLUS: - arg0 = simplify_giv_expr (XEXP (x, 0), benefit); - arg1 = simplify_giv_expr (XEXP (x, 1), benefit); + arg0 = simplify_giv_expr (loop, XEXP (x, 0), ext_val, benefit); + arg1 = simplify_giv_expr (loop, XEXP (x, 1), ext_val, benefit); if (arg0 == 0 || arg1 == 0) return NULL_RTX; @@ -6282,7 +6396,7 @@ simplify_giv_expr (x, benefit) case CONST_INT: case USE: /* Adding two invariants must result in an invariant, so enclose - addition operation inside a USE and return it. */ + addition operation inside a USE and return it. */ if (GET_CODE (arg0) == USE) arg0 = XEXP (arg0, 0); if (GET_CODE (arg1) == USE) @@ -6306,10 +6420,14 @@ simplify_giv_expr (x, benefit) case PLUS: /* (a + invar_1) + invar_2. Associate. */ - return simplify_giv_expr ( - gen_rtx_PLUS (mode, XEXP (arg0, 0), - gen_rtx_PLUS (mode, XEXP (arg0, 1), arg1)), - benefit); + return + simplify_giv_expr (loop, + gen_rtx_PLUS (mode, + XEXP (arg0, 0), + gen_rtx_PLUS (mode, + XEXP (arg0, 1), + arg1)), + ext_val, benefit); default: abort (); @@ -6329,11 +6447,13 @@ simplify_giv_expr (x, benefit) tem = arg0, arg0 = arg1, arg1 = tem; if (GET_CODE (arg1) == PLUS) - return simplify_giv_expr (gen_rtx_PLUS (mode, - gen_rtx_PLUS (mode, arg0, - XEXP (arg1, 0)), - XEXP (arg1, 1)), - benefit); + return + simplify_giv_expr (loop, + gen_rtx_PLUS (mode, + gen_rtx_PLUS (mode, arg0, + XEXP (arg1, 0)), + XEXP (arg1, 1)), + ext_val, benefit); /* Now must have MULT + MULT. Distribute if same biv, else not giv. */ if (GET_CODE (arg0) != MULT || GET_CODE (arg1) != MULT) @@ -6342,24 +6462,27 @@ simplify_giv_expr (x, benefit) if (!rtx_equal_p (arg0, arg1)) return NULL_RTX; - return simplify_giv_expr (gen_rtx_MULT (mode, + return simplify_giv_expr (loop, + gen_rtx_MULT (mode, XEXP (arg0, 0), gen_rtx_PLUS (mode, XEXP (arg0, 1), XEXP (arg1, 1))), - benefit); + ext_val, benefit); case MINUS: /* Handle "a - b" as "a + b * (-1)". */ - return simplify_giv_expr (gen_rtx_PLUS (mode, + return simplify_giv_expr (loop, + gen_rtx_PLUS (mode, XEXP (x, 0), - gen_rtx_MULT (mode, XEXP (x, 1), + gen_rtx_MULT (mode, + XEXP (x, 1), constm1_rtx)), - benefit); + ext_val, benefit); case MULT: - arg0 = simplify_giv_expr (XEXP (x, 0), benefit); - arg1 = simplify_giv_expr (XEXP (x, 1), benefit); + arg0 = simplify_giv_expr (loop, XEXP (x, 0), ext_val, benefit); + arg1 = simplify_giv_expr (loop, XEXP (x, 1), ext_val, benefit); if (arg0 == 0 || arg1 == 0) return NULL_RTX; @@ -6390,44 +6513,62 @@ simplify_giv_expr (x, benefit) return GEN_INT (INTVAL (arg0) * INTVAL (arg1)); case USE: - /* invar * invar. It is a giv, but very few of these will - actually pay off, so limit to simple registers. */ + /* invar * invar is a giv, but attempt to simplify it somehow. */ if (GET_CODE (arg1) != CONST_INT) return NULL_RTX; arg0 = XEXP (arg0, 0); - if (GET_CODE (arg0) == REG) - tem = gen_rtx_MULT (mode, arg0, arg1); - else if (GET_CODE (arg0) == MULT - && GET_CODE (XEXP (arg0, 0)) == REG - && GET_CODE (XEXP (arg0, 1)) == CONST_INT) + if (GET_CODE (arg0) == MULT) { - tem = gen_rtx_MULT (mode, XEXP (arg0, 0), - GEN_INT (INTVAL (XEXP (arg0, 1)) - * INTVAL (arg1))); + /* (invar_0 * invar_1) * invar_2. Associate. */ + return simplify_giv_expr (loop, + gen_rtx_MULT (mode, + XEXP (arg0, 0), + gen_rtx_MULT (mode, + XEXP (arg0, + 1), + arg1)), + ext_val, benefit); } - else - return NULL_RTX; - return gen_rtx_USE (mode, tem); + /* Porpagate the MULT expressions to the intermost nodes. */ + else if (GET_CODE (arg0) == PLUS) + { + /* (invar_0 + invar_1) * invar_2. Distribute. */ + return simplify_giv_expr (loop, + gen_rtx_PLUS (mode, + gen_rtx_MULT (mode, + XEXP (arg0, + 0), + arg1), + gen_rtx_MULT (mode, + XEXP (arg0, + 1), + arg1)), + ext_val, benefit); + } + return gen_rtx_USE (mode, gen_rtx_MULT (mode, arg0, arg1)); case MULT: /* (a * invar_1) * invar_2. Associate. */ - return simplify_giv_expr (gen_rtx_MULT (mode, XEXP (arg0, 0), + return simplify_giv_expr (loop, + gen_rtx_MULT (mode, + XEXP (arg0, 0), gen_rtx_MULT (mode, XEXP (arg0, 1), arg1)), - benefit); + ext_val, benefit); case PLUS: /* (a + invar_1) * invar_2. Distribute. */ - return simplify_giv_expr (gen_rtx_PLUS (mode, + return simplify_giv_expr (loop, + gen_rtx_PLUS (mode, gen_rtx_MULT (mode, XEXP (arg0, 0), arg1), gen_rtx_MULT (mode, XEXP (arg0, 1), arg1)), - benefit); + ext_val, benefit); default: abort (); @@ -6438,73 +6579,122 @@ simplify_giv_expr (x, benefit) if (GET_CODE (XEXP (x, 1)) != CONST_INT) return 0; - return simplify_giv_expr (gen_rtx_MULT (mode, - XEXP (x, 0), - GEN_INT ((HOST_WIDE_INT) 1 - << INTVAL (XEXP (x, 1)))), - benefit); + return + simplify_giv_expr (loop, + gen_rtx_MULT (mode, + XEXP (x, 0), + GEN_INT ((HOST_WIDE_INT) 1 + << INTVAL (XEXP (x, 1)))), + ext_val, benefit); case NEG: /* "-a" is "a * (-1)" */ - return simplify_giv_expr (gen_rtx_MULT (mode, XEXP (x, 0), constm1_rtx), - benefit); + return simplify_giv_expr (loop, + gen_rtx_MULT (mode, XEXP (x, 0), constm1_rtx), + ext_val, benefit); case NOT: /* "~a" is "-a - 1". Silly, but easy. */ - return simplify_giv_expr (gen_rtx_MINUS (mode, + return simplify_giv_expr (loop, + gen_rtx_MINUS (mode, gen_rtx_NEG (mode, XEXP (x, 0)), const1_rtx), - benefit); + ext_val, benefit); case USE: /* Already in proper form for invariant. */ return x; + case SIGN_EXTEND: + case ZERO_EXTEND: + case TRUNCATE: + /* Conditionally recognize extensions of simple IVs. After we've + computed loop traversal counts and verified the range of the + source IV, we'll reevaluate this as a GIV. */ + if (*ext_val == NULL_RTX) + { + arg0 = simplify_giv_expr (loop, XEXP (x, 0), ext_val, benefit); + if (arg0 && *ext_val == NULL_RTX && GET_CODE (arg0) == REG) + { + *ext_val = gen_rtx_fmt_e (GET_CODE (x), mode, arg0); + return arg0; + } + } + goto do_default; + case REG: /* If this is a new register, we can't deal with it. */ if (REGNO (x) >= max_reg_before_loop) return 0; /* Check for biv or giv. */ - switch (REG_IV_TYPE (REGNO (x))) + switch (REG_IV_TYPE (ivs, REGNO (x))) { case BASIC_INDUCT: return x; case GENERAL_INDUCT: { - struct induction *v = REG_IV_INFO (REGNO (x)); + struct induction *v = REG_IV_INFO (ivs, REGNO (x)); /* Form expression from giv and add benefit. Ensure this giv can derive another and subtract any needed adjustment if so. */ - *benefit += v->benefit; + + /* Increasing the benefit here is risky. The only case in which it + is arguably correct is if this is the only use of V. In other + cases, this will artificially inflate the benefit of the current + giv, and lead to suboptimal code. Thus, it is disabled, since + potentially not reducing an only marginally beneficial giv is + less harmful than reducing many givs that are not really + beneficial. */ + { + rtx single_use = regs->array[REGNO (x)].single_usage; + if (single_use && single_use != const0_rtx) + *benefit += v->benefit; + } + if (v->cant_derive) return 0; - tem = gen_rtx_PLUS (mode, gen_rtx_MULT (mode, v->src_reg, - v->mult_val), - v->add_val); + tem = gen_rtx_PLUS (mode, gen_rtx_MULT (mode, + v->src_reg, v->mult_val), + v->add_val); + if (v->derive_adjustment) tem = gen_rtx_MINUS (mode, tem, v->derive_adjustment); - return simplify_giv_expr (tem, benefit); + arg0 = simplify_giv_expr (loop, tem, ext_val, benefit); + if (*ext_val) + { + if (!v->ext_dependent) + return arg0; + } + else + { + *ext_val = v->ext_dependent; + return arg0; + } + return 0; } default: + do_default: /* If it isn't an induction variable, and it is invariant, we may be able to simplify things further by looking through the bits we just moved outside the loop. */ - if (invariant_p (x) == 1) + if (loop_invariant_p (loop, x) == 1) { struct movable *m; + struct loop_movables *movables = LOOP_MOVABLES (loop); - for (m = the_movables; m ; m = m->next) + for (m = movables->head; m; m = m->next) if (rtx_equal_p (x, m->set_dest)) { /* Ok, we found a match. Substitute and simplify. */ - /* If we match another movable, we must use that, as + /* If we match another movable, we must use that, as this one is going away. */ if (m->match) - return simplify_giv_expr (m->match->set_dest, benefit); + return simplify_giv_expr (loop, m->match->set_dest, + ext_val, benefit); /* If consec is non-zero, this is a member of a group of instructions that were moved together. We handle this @@ -6514,7 +6704,11 @@ simplify_giv_expr (x, benefit) { int i = m->consec; tem = m->insn; - do { tem = NEXT_INSN (tem); } while (--i > 0); + do + { + tem = NEXT_INSN (tem); + } + while (--i > 0); tem = find_reg_note (tem, REG_EQUAL, NULL_RTX); if (tem) @@ -6522,8 +6716,8 @@ simplify_giv_expr (x, benefit) } else { - tem = single_set (m->insn); - if (tem) + tem = single_set (m->insn); + if (tem) tem = SET_SRC (tem); } @@ -6538,16 +6732,18 @@ simplify_giv_expr (x, benefit) || GET_CODE (tem) == CONST_INT || GET_CODE (tem) == SYMBOL_REF) { - tem = simplify_giv_expr (tem, benefit); + tem = simplify_giv_expr (loop, tem, ext_val, + benefit); if (tem) return tem; } else if (GET_CODE (tem) == CONST - && GET_CODE (XEXP (tem, 0)) == PLUS - && GET_CODE (XEXP (XEXP (tem, 0), 0)) == SYMBOL_REF - && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT) + && GET_CODE (XEXP (tem, 0)) == PLUS + && GET_CODE (XEXP (XEXP (tem, 0), 0)) == SYMBOL_REF + && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT) { - tem = simplify_giv_expr (XEXP (tem, 0), benefit); + tem = simplify_giv_expr (loop, XEXP (tem, 0), + ext_val, benefit); if (tem) return tem; } @@ -6565,7 +6761,7 @@ simplify_giv_expr (x, benefit) if (GET_CODE (x) == USE) x = XEXP (x, 0); - if (invariant_p (x) == 1) + if (loop_invariant_p (loop, x) == 1) { if (GET_CODE (x) == CONST_INT) return x; @@ -6651,16 +6847,20 @@ sge_plus (mode, x, y) *MULT_VAL and *ADD_VAL. */ static int -consec_sets_giv (first_benefit, p, src_reg, dest_reg, - add_val, mult_val, last_consec_insn) +consec_sets_giv (loop, first_benefit, p, src_reg, dest_reg, + add_val, mult_val, ext_val, last_consec_insn) + const struct loop *loop; int first_benefit; rtx p; rtx src_reg; rtx dest_reg; rtx *add_val; rtx *mult_val; + rtx *ext_val; rtx *last_consec_insn; { + struct loop_ivs *ivs = LOOP_IVS (loop); + struct loop_regs *regs = LOOP_REGS (loop); int count; enum rtx_code code; int benefit; @@ -6668,25 +6868,30 @@ consec_sets_giv (first_benefit, p, src_reg, dest_reg, rtx set; /* Indicate that this is a giv so that we can update the value produced in - each insn of the multi-insn sequence. + each insn of the multi-insn sequence. This induction structure will be used only by the call to general_induction_var below, so we can allocate it on our stack. If this is a giv, our caller will replace the induct var entry with a new induction structure. */ - struct induction *v - = (struct induction *) alloca (sizeof (struct induction)); + struct induction *v; + + if (REG_IV_TYPE (ivs, REGNO (dest_reg)) != UNKNOWN_INDUCT) + return 0; + + v = (struct induction *) alloca (sizeof (struct induction)); v->src_reg = src_reg; v->mult_val = *mult_val; v->add_val = *add_val; v->benefit = first_benefit; v->cant_derive = 0; v->derive_adjustment = 0; + v->ext_dependent = NULL_RTX; - REG_IV_TYPE (REGNO (dest_reg)) = GENERAL_INDUCT; - REG_IV_INFO (REGNO (dest_reg)) = v; + REG_IV_TYPE (ivs, REGNO (dest_reg)) = GENERAL_INDUCT; + REG_IV_INFO (ivs, REGNO (dest_reg)) = v; - count = VARRAY_INT (n_times_set, REGNO (dest_reg)) - 1; + count = regs->array[REGNO (dest_reg)].n_times_set - 1; while (count > 0) { @@ -6701,12 +6906,14 @@ consec_sets_giv (first_benefit, p, src_reg, dest_reg, && (set = single_set (p)) && GET_CODE (SET_DEST (set)) == REG && SET_DEST (set) == dest_reg - && (general_induction_var (SET_SRC (set), &src_reg, - add_val, mult_val, 0, &benefit) + && (general_induction_var (loop, SET_SRC (set), &src_reg, + add_val, mult_val, ext_val, 0, + &benefit, VOIDmode) /* Giv created by equivalent expression. */ || ((temp = find_reg_note (p, REG_EQUAL, NULL_RTX)) - && general_induction_var (XEXP (temp, 0), &src_reg, - add_val, mult_val, 0, &benefit))) + && general_induction_var (loop, XEXP (temp, 0), &src_reg, + add_val, mult_val, ext_val, 0, + &benefit, VOIDmode))) && src_reg == v->src_reg) { if (find_reg_note (p, REG_RETVAL, NULL_RTX)) @@ -6715,7 +6922,7 @@ consec_sets_giv (first_benefit, p, src_reg, dest_reg, count--; v->mult_val = *mult_val; v->add_val = *add_val; - v->benefit = benefit; + v->benefit += benefit; } else if (code != NOTE) { @@ -6728,21 +6935,22 @@ consec_sets_giv (first_benefit, p, src_reg, dest_reg, && CONSTANT_P (SET_SRC (set))) continue; - REG_IV_TYPE (REGNO (dest_reg)) = UNKNOWN_INDUCT; + REG_IV_TYPE (ivs, REGNO (dest_reg)) = UNKNOWN_INDUCT; return 0; } } + REG_IV_TYPE (ivs, REGNO (dest_reg)) = UNKNOWN_INDUCT; *last_consec_insn = p; return v->benefit; } /* Return an rtx, if any, that expresses giv G2 as a function of the register represented by G1. If no such expression can be found, or it is clear that - it cannot possibly be a valid address, 0 is returned. + it cannot possibly be a valid address, 0 is returned. To perform the computation, we note that - G1 = x * v + a and + G1 = x * v + a and G2 = y * v + b where `v' is the biv. @@ -6783,11 +6991,11 @@ express_from_1 (a, b, mult) ra = XEXP (a, 0), oa = XEXP (a, 1); if (GET_CODE (ra) == PLUS) - tmp = ra, ra = oa, oa = tmp; + tmp = ra, ra = oa, oa = tmp; rb = XEXP (b, 0), ob = XEXP (b, 1); if (GET_CODE (rb) == PLUS) - tmp = rb, rb = ob, ob = tmp; + tmp = rb, rb = ob, ob = tmp; if (rtx_equal_p (ra, rb)) /* We matched: remove one reg completely. */ @@ -6800,7 +7008,7 @@ express_from_1 (a, b, mult) a = ra, b = ob; else { - /* Indicates an extra register in B. Strip one level from B and + /* Indicates an extra register in B. Strip one level from B and recurse, hoping B was the higher order expression. */ ob = express_from_1 (a, ob, mult); if (ob == NULL_RTX) @@ -6831,6 +7039,13 @@ express_from_1 (a, b, mult) { return plus_constant (b, -INTVAL (a) * INTVAL (mult)); } + else if (CONSTANT_P (a)) + { + enum machine_mode mode_a = GET_MODE (a); + enum machine_mode mode_b = GET_MODE (b); + enum machine_mode mode = mode_b == VOIDmode ? mode_a : mode_b; + return simplify_gen_binary (MINUS, mode, b, a); + } else if (GET_CODE (b) == PLUS) { if (rtx_equal_p (a, XEXP (b, 0))) @@ -6859,8 +7074,8 @@ express_from (g1, g2) && GET_CODE (g2->mult_val) == CONST_INT) { if (g1->mult_val == const0_rtx - || INTVAL (g2->mult_val) % INTVAL (g1->mult_val) != 0) - return NULL_RTX; + || INTVAL (g2->mult_val) % INTVAL (g1->mult_val) != 0) + return NULL_RTX; mult = GEN_INT (INTVAL (g2->mult_val) / INTVAL (g1->mult_val)); } else if (rtx_equal_p (g1->mult_val, g2->mult_val)) @@ -6873,6 +7088,30 @@ express_from (g1, g2) add = express_from_1 (g1->add_val, g2->add_val, mult); if (add == NULL_RTX) + { + /* Failed. If we've got a multiplication factor between G1 and G2, + scale G1's addend and try again. */ + if (INTVAL (mult) > 1) + { + rtx g1_add_val = g1->add_val; + if (GET_CODE (g1_add_val) == MULT + && GET_CODE (XEXP (g1_add_val, 1)) == CONST_INT) + { + HOST_WIDE_INT m; + m = INTVAL (mult) * INTVAL (XEXP (g1_add_val, 1)); + g1_add_val = gen_rtx_MULT (GET_MODE (g1_add_val), + XEXP (g1_add_val, 0), GEN_INT (m)); + } + else + { + g1_add_val = gen_rtx_MULT (GET_MODE (g1_add_val), g1_add_val, + mult); + } + + add = express_from_1 (g1_add_val, g2->add_val, const1_rtx); + } + } + if (add == NULL_RTX) return NULL_RTX; /* Form simplified final result. */ @@ -6894,10 +7133,9 @@ express_from (g1, g2) mult = gen_rtx_PLUS (g2->mode, mult, XEXP (add, 0)); add = tem; } - + return gen_rtx_PLUS (g2->mode, mult, add); } - } /* Return an rtx, if any, that expresses giv G2 as a function of the register @@ -6909,25 +7147,36 @@ static rtx combine_givs_p (g1, g2) struct induction *g1, *g2; { - rtx tem = express_from (g1, g2); + rtx comb, ret; + + /* With the introduction of ext dependent givs, we must care for modes. + G2 must not use a wider mode than G1. */ + if (GET_MODE_SIZE (g1->mode) < GET_MODE_SIZE (g2->mode)) + return NULL_RTX; + + ret = comb = express_from (g1, g2); + if (comb == NULL_RTX) + return NULL_RTX; + if (g1->mode != g2->mode) + ret = gen_lowpart (g2->mode, comb); /* If these givs are identical, they can be combined. We use the results of express_from because the addends are not in a canonical form, so rtx_equal_p is a weaker test. */ /* But don't combine a DEST_REG giv with a DEST_ADDR giv; we want the combination to be the other way round. */ - if (tem == g1->dest_reg + if (comb == g1->dest_reg && (g1->giv_type == DEST_REG || g2->giv_type == DEST_ADDR)) { - return g1->dest_reg; + return ret; } /* If G2 can be expressed as a function of G1 and that function is valid as an address and no more expensive than using a register for G2, the expression of G2 in terms of G1 can be used. */ - if (tem != NULL_RTX + if (ret != NULL_RTX && g2->giv_type == DEST_ADDR - && memory_address_p (g2->mem_mode, tem) + && memory_address_p (GET_MODE (g2->mem), ret) /* ??? Looses, especially with -fforce-addr, where *g2->location will always be a register, and so anything more complicated gets discarded. */ @@ -6940,12 +7189,199 @@ combine_givs_p (g1, g2) #endif ) { - return tem; + return ret; } return NULL_RTX; } +/* Check each extension dependent giv in this class to see if its + root biv is safe from wrapping in the interior mode, which would + make the giv illegal. */ + +static void +check_ext_dependent_givs (bl, loop_info) + struct iv_class *bl; + struct loop_info *loop_info; +{ + int ze_ok = 0, se_ok = 0, info_ok = 0; + enum machine_mode biv_mode = GET_MODE (bl->biv->src_reg); + HOST_WIDE_INT start_val; + unsigned HOST_WIDE_INT u_end_val = 0; + unsigned HOST_WIDE_INT u_start_val = 0; + rtx incr = pc_rtx; + struct induction *v; + + /* Make sure the iteration data is available. We must have + constants in order to be certain of no overflow. */ + /* ??? An unknown iteration count with an increment of +-1 + combined with friendly exit tests of against an invariant + value is also ameanable to optimization. Not implemented. */ + if (loop_info->n_iterations > 0 + && bl->initial_value + && GET_CODE (bl->initial_value) == CONST_INT + && (incr = biv_total_increment (bl)) + && GET_CODE (incr) == CONST_INT + /* Make sure the host can represent the arithmetic. */ + && HOST_BITS_PER_WIDE_INT >= GET_MODE_BITSIZE (biv_mode)) + { + unsigned HOST_WIDE_INT abs_incr, total_incr; + HOST_WIDE_INT s_end_val; + int neg_incr; + + info_ok = 1; + start_val = INTVAL (bl->initial_value); + u_start_val = start_val; + + neg_incr = 0, abs_incr = INTVAL (incr); + if (INTVAL (incr) < 0) + neg_incr = 1, abs_incr = -abs_incr; + total_incr = abs_incr * loop_info->n_iterations; + + /* Check for host arithmatic overflow. */ + if (total_incr / loop_info->n_iterations == abs_incr) + { + unsigned HOST_WIDE_INT u_max; + HOST_WIDE_INT s_max; + + u_end_val = start_val + (neg_incr ? -total_incr : total_incr); + s_end_val = u_end_val; + u_max = GET_MODE_MASK (biv_mode); + s_max = u_max >> 1; + + /* Check zero extension of biv ok. */ + if (start_val >= 0 + /* Check for host arithmatic overflow. */ + && (neg_incr + ? u_end_val < u_start_val + : u_end_val > u_start_val) + /* Check for target arithmetic overflow. */ + && (neg_incr + ? 1 /* taken care of with host overflow */ + : u_end_val <= u_max)) + { + ze_ok = 1; + } + + /* Check sign extension of biv ok. */ + /* ??? While it is true that overflow with signed and pointer + arithmetic is undefined, I fear too many programmers don't + keep this fact in mind -- myself included on occasion. + So leave alone with the signed overflow optimizations. */ + if (start_val >= -s_max - 1 + /* Check for host arithmatic overflow. */ + && (neg_incr + ? s_end_val < start_val + : s_end_val > start_val) + /* Check for target arithmetic overflow. */ + && (neg_incr + ? s_end_val >= -s_max - 1 + : s_end_val <= s_max)) + { + se_ok = 1; + } + } + } + + /* Invalidate givs that fail the tests. */ + for (v = bl->giv; v; v = v->next_iv) + if (v->ext_dependent) + { + enum rtx_code code = GET_CODE (v->ext_dependent); + int ok = 0; + + switch (code) + { + case SIGN_EXTEND: + ok = se_ok; + break; + case ZERO_EXTEND: + ok = ze_ok; + break; + + case TRUNCATE: + /* We don't know whether this value is being used as either + signed or unsigned, so to safely truncate we must satisfy + both. The initial check here verifies the BIV itself; + once that is successful we may check its range wrt the + derived GIV. */ + if (se_ok && ze_ok) + { + enum machine_mode outer_mode = GET_MODE (v->ext_dependent); + unsigned HOST_WIDE_INT max = GET_MODE_MASK (outer_mode) >> 1; + + /* We know from the above that both endpoints are nonnegative, + and that there is no wrapping. Verify that both endpoints + are within the (signed) range of the outer mode. */ + if (u_start_val <= max && u_end_val <= max) + ok = 1; + } + break; + + default: + abort (); + } + + if (ok) + { + if (loop_dump_stream) + { + fprintf (loop_dump_stream, + "Verified ext dependent giv at %d of reg %d\n", + INSN_UID (v->insn), bl->regno); + } + } + else + { + if (loop_dump_stream) + { + const char *why; + + if (info_ok) + why = "biv iteration values overflowed"; + else + { + if (incr == pc_rtx) + incr = biv_total_increment (bl); + if (incr == const1_rtx) + why = "biv iteration info incomplete; incr by 1"; + else + why = "biv iteration info incomplete"; + } + + fprintf (loop_dump_stream, + "Failed ext dependent giv at %d, %s\n", + INSN_UID (v->insn), why); + } + v->ignore = 1; + bl->all_reduced = 0; + } + } +} + +/* Generate a version of VALUE in a mode appropriate for initializing V. */ + +rtx +extend_value_for_giv (v, value) + struct induction *v; + rtx value; +{ + rtx ext_dep = v->ext_dependent; + + if (! ext_dep) + return value; + + /* Recall that check_ext_dependent_givs verified that the known bounds + of a biv did not overflow or wrap with respect to the extension for + the giv. Therefore, constants need no additional adjustment. */ + if (CONSTANT_P (value) && GET_MODE (value) == VOIDmode) + return value; + + /* Otherwise, we must adjust the value to compensate for the + differing modes of the biv and the giv. */ + return gen_rtx_fmt_e (GET_CODE (ext_dep), GET_MODE (ext_dep), value); +} + struct combine_givs_stats { int giv_number; @@ -6953,9 +7389,14 @@ struct combine_givs_stats }; static int -cmp_combine_givs_stats (x, y) - struct combine_givs_stats *x, *y; +cmp_combine_givs_stats (xp, yp) + const PTR xp; + const PTR yp; { + const struct combine_givs_stats * const x = + (const struct combine_givs_stats *) xp; + const struct combine_givs_stats * const y = + (const struct combine_givs_stats *) yp; int d; d = y->total_benefit - x->total_benefit; /* Stabilize the sort. */ @@ -6970,7 +7411,8 @@ cmp_combine_givs_stats (x, y) giv. Also, update BENEFIT and related fields for cost/benefit analysis. */ static void -combine_givs (bl) +combine_givs (regs, bl) + struct loop_regs *regs; struct iv_class *bl; { /* Additional benefit to add for being combined multiple times. */ @@ -6994,11 +7436,8 @@ combine_givs (bl) if (!g1->ignore) giv_array[i++] = g1; - stats = (struct combine_givs_stats *) alloca (giv_count * sizeof (*stats)); - bzero ((char *) stats, giv_count * sizeof (*stats)); - - can_combine = (rtx *) alloca (giv_count * giv_count * sizeof(rtx)); - bzero ((char *) can_combine, giv_count * giv_count * sizeof(rtx)); + stats = (struct combine_givs_stats *) xcalloc (giv_count, sizeof (*stats)); + can_combine = (rtx *) xcalloc (giv_count, giv_count * sizeof (rtx)); for (i = 0; i < giv_count; i++) { @@ -7011,11 +7450,11 @@ combine_givs (bl) /* If a DEST_REG GIV is used only once, do not allow it to combine with anything, for in doing so we will gain nothing that cannot be had by simply letting the GIV with which we would have combined - to be reduced on its own. The losage shows up in particular with + to be reduced on its own. The losage shows up in particular with DEST_ADDR targets on hosts with reg+reg addressing, though it can be seen elsewhere as well. */ if (g1->giv_type == DEST_REG - && (single_use = VARRAY_RTX (reg_single_usage, REGNO (g1->dest_reg))) + && (single_use = regs->array[REGNO (g1->dest_reg)].single_usage) && single_use != const0_rtx) continue; @@ -7032,7 +7471,7 @@ combine_givs (bl) if (g1 != g2 && (this_combine = combine_givs_p (g1, g2)) != NULL_RTX) { - can_combine[i*giv_count + j] = this_combine; + can_combine[i * giv_count + j] = this_combine; this_benefit += g2->benefit + extra_benefit; } } @@ -7041,7 +7480,7 @@ combine_givs (bl) /* Iterate, combining until we can't. */ restart: - qsort (stats, giv_count, sizeof(*stats), cmp_combine_givs_stats); + qsort (stats, giv_count, sizeof (*stats), cmp_combine_givs_stats); if (loop_dump_stream) { @@ -7050,7 +7489,7 @@ restart: { g1 = giv_array[stats[k].giv_number]; if (!g1->combined_with && !g1->same) - fprintf (loop_dump_stream, " {%d, %d}", + fprintf (loop_dump_stream, " {%d, %d}", INSN_UID (giv_array[stats[k].giv_number]->insn), stats[k].total_benefit); } @@ -7071,14 +7510,21 @@ restart: for (j = 0; j < giv_count; j++) { g2 = giv_array[j]; - if (g1 != g2 && can_combine[i*giv_count + j] + if (g1 != g2 && can_combine[i * giv_count + j] /* If it has already been combined, skip. */ && ! g2->same && ! g2->combined_with) { int l; - g2->new_reg = can_combine[i*giv_count + j]; + g2->new_reg = can_combine[i * giv_count + j]; g2->same = g1; + /* For destination, we now may replace by mem expression instead + of register. This changes the costs considerably, so add the + compensation. */ + if (g2->giv_type == DEST_ADDR) + g2->benefit = (g2->benefit + reg_address_cost + - address_cost (g2->new_reg, + GET_MODE (g2->mem))); g1->combined_with++; g1->lifetime += g2->lifetime; @@ -7089,20 +7535,21 @@ restart: longer be necessary. */ if (! g2->replaceable && REG_USERVAR_P (g2->dest_reg)) g1_add_benefit -= copy_cost; - + /* To help optimize the next set of combinations, remove this giv from the benefits of other potential mates. */ for (l = 0; l < giv_count; ++l) { int m = stats[l].giv_number; - if (can_combine[m*giv_count + j]) + if (can_combine[m * giv_count + j]) stats[l].total_benefit -= g2->benefit + extra_benefit; } if (loop_dump_stream) fprintf (loop_dump_stream, - "giv at %d combined with giv at %d\n", - INSN_UID (g2->insn), INSN_UID (g1->insn)); + "giv at %d combined with giv at %d; new benefit %d + %d, lifetime %d\n", + INSN_UID (g2->insn), INSN_UID (g1->insn), + g1->benefit, g1_add_benefit, g1->lifetime); } } @@ -7113,14 +7560,14 @@ restart: for (j = 0; j < giv_count; ++j) { int m = stats[j].giv_number; - if (can_combine[m*giv_count + i]) + if (can_combine[m * giv_count + i]) stats[j].total_benefit -= g1->benefit + extra_benefit; } g1->benefit += g1_add_benefit; /* We've finished with this giv, and everything it touched. - Restart the combination so that proper weights for the + Restart the combination so that proper weights for the rest of the givs are properly taken into account. */ /* ??? Ideally we would compact the arrays at this point, so as to not cover old ground. But sanely compacting @@ -7128,478 +7575,180 @@ restart: goto restart; } } -} - -struct recombine_givs_stats -{ - int giv_number; - int start_luid, end_luid; -}; -/* Used below as comparison function for qsort. We want a ascending luid - when scanning the array starting at the end, thus the arguments are - used in reverse. */ -static int -cmp_recombine_givs_stats (x, y) - struct recombine_givs_stats *x, *y; -{ - int d; - d = y->start_luid - x->start_luid; - /* Stabilize the sort. */ - if (!d) - d = y->giv_number - x->giv_number; - return d; + /* Clean up. */ + free (stats); + free (can_combine); } + +/* Generate sequence for REG = B * M + A. */ -/* Scan X, which is a part of INSN, for the end of life of a giv. Also - look for the start of life of a giv where the start has not been seen - yet to unlock the search for the end of its life. - Only consider givs that belong to BIV. - Return the total number of lifetime ends that have been found. */ -static int -find_life_end (x, stats, insn, biv) - rtx x, insn, biv; - struct recombine_givs_stats *stats; +static rtx +gen_add_mult (b, m, a, reg) + rtx b; /* initial value of basic induction variable */ + rtx m; /* multiplicative constant */ + rtx a; /* additive constant */ + rtx reg; /* destination register */ { - enum rtx_code code; - char *fmt; - int i, j; - int retval; + rtx seq; + rtx result; - code = GET_CODE (x); - switch (code) - { - case SET: - { - rtx reg = SET_DEST (x); - if (GET_CODE (reg) == REG) - { - int regno = REGNO (reg); - struct induction *v = REG_IV_INFO (regno); + start_sequence (); + /* Use unsigned arithmetic. */ + result = expand_mult_add (b, reg, m, a, GET_MODE (reg), 1); + if (reg != result) + emit_move_insn (reg, result); + seq = gen_sequence (); + end_sequence (); - if (REG_IV_TYPE (regno) == GENERAL_INDUCT - && ! v->ignore - && v->src_reg == biv - && stats[v->ix].end_luid <= 0) - { - /* If we see a 0 here for end_luid, it means that we have - scanned the entire loop without finding any use at all. - We must not predicate this code on a start_luid match - since that would make the test fail for givs that have - been hoisted out of inner loops. */ - if (stats[v->ix].end_luid == 0) - { - stats[v->ix].end_luid = stats[v->ix].start_luid; - return 1 + find_life_end (SET_SRC (x), stats, insn, biv); - } - else if (stats[v->ix].start_luid == INSN_LUID (insn)) - stats[v->ix].end_luid = 0; - } - return find_life_end (SET_SRC (x), stats, insn, biv); - } - break; - } - case REG: - { - int regno = REGNO (x); - struct induction *v = REG_IV_INFO (regno); + return seq; +} - if (REG_IV_TYPE (regno) == GENERAL_INDUCT - && ! v->ignore - && v->src_reg == biv - && stats[v->ix].end_luid == 0) - { - while (INSN_UID (insn) >= max_uid_for_loop) - insn = NEXT_INSN (insn); - stats[v->ix].end_luid = INSN_LUID (insn); - return 1; - } - return 0; - } - case LABEL_REF: - case CONST_DOUBLE: - case CONST_INT: - case CONST: - return 0; - default: - break; - } - fmt = GET_RTX_FORMAT (code); - retval = 0; - for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - { - if (fmt[i] == 'e') - retval += find_life_end (XEXP (x, i), stats, insn, biv); - else if (fmt[i] == 'E') - for (j = XVECLEN (x, i) - 1; j >= 0; j--) - retval += find_life_end (XVECEXP (x, i, j), stats, insn, biv); - } - return retval; -} +/* Update registers created in insn sequence SEQ. */ -/* For each giv that has been combined with another, look if - we can combine it with the most recently used one instead. - This tends to shorten giv lifetimes, and helps the next step: - try to derive givs from other givs. */ static void -recombine_givs (bl, loop_start, loop_end, unroll_p) - struct iv_class *bl; - rtx loop_start, loop_end; - int unroll_p; +loop_regs_update (loop, seq) + const struct loop *loop ATTRIBUTE_UNUSED; + rtx seq; { - struct induction *v, **giv_array, *last_giv; - struct recombine_givs_stats *stats; - int giv_count; - int i, rescan; - int ends_need_computing; + /* Update register info for alias analysis. */ - for (giv_count = 0, v = bl->giv; v; v = v->next_iv) + if (GET_CODE (seq) == SEQUENCE) { - if (! v->ignore) - giv_count++; + int i; + for (i = 0; i < XVECLEN (seq, 0); ++i) + { + rtx set = single_set (XVECEXP (seq, 0, i)); + if (set && GET_CODE (SET_DEST (set)) == REG) + record_base_value (REGNO (SET_DEST (set)), SET_SRC (set), 0); + } } - giv_array - = (struct induction **) alloca (giv_count * sizeof (struct induction *)); - stats = (struct recombine_givs_stats *) alloca (giv_count * sizeof *stats); - - /* Initialize stats and set up the ix field for each giv in stats to name - the corresponding index into stats. */ - for (i = 0, v = bl->giv; v; v = v->next_iv) + else { - rtx p; - - if (v->ignore) - continue; - giv_array[i] = v; - stats[i].giv_number = i; - /* If this giv has been hoisted out of an inner loop, use the luid of - the previous insn. */ - for (p = v->insn; INSN_UID (p) >= max_uid_for_loop; ) - p = PREV_INSN (p); - stats[i].start_luid = INSN_LUID (p); - v->ix = i; - i++; + rtx set = single_set (seq); + if (set && GET_CODE (SET_DEST (set)) == REG) + record_base_value (REGNO (SET_DEST (set)), SET_SRC (set), 0); } +} - qsort (stats, giv_count, sizeof(*stats), cmp_recombine_givs_stats); - /* Do the actual most-recently-used recombination. */ - for (last_giv = 0, i = giv_count - 1; i >= 0; i--) - { - v = giv_array[stats[i].giv_number]; - if (v->same) - { - struct induction *old_same = v->same; - rtx new_combine; - - /* combine_givs_p actually says if we can make this transformation. - The other tests are here only to avoid keeping a giv alive - that could otherwise be eliminated. */ - if (last_giv - && ((old_same->maybe_dead && ! old_same->combined_with) - || ! last_giv->maybe_dead - || last_giv->combined_with) - && (new_combine = combine_givs_p (last_giv, v))) - { - old_same->combined_with--; - v->new_reg = new_combine; - v->same = last_giv; - last_giv->combined_with++; - /* No need to update lifetimes / benefits here since we have - already decided what to reduce. */ +/* EMIT code before BEFORE_BB/BEFORE_INSN to set REG = B * M + A. */ - if (loop_dump_stream) - { - fprintf (loop_dump_stream, - "giv at %d recombined with giv at %d as ", - INSN_UID (v->insn), INSN_UID (last_giv->insn)); - print_rtl (loop_dump_stream, v->new_reg); - putc ('\n', loop_dump_stream); - } - continue; - } - v = v->same; - } - else if (v->giv_type != DEST_REG) - continue; - if (! last_giv - || (last_giv->maybe_dead && ! last_giv->combined_with) - || ! v->maybe_dead - || v->combined_with) - last_giv = v; - } +void +loop_iv_add_mult_emit_before (loop, b, m, a, reg, before_bb, before_insn) + const struct loop *loop; + rtx b; /* initial value of basic induction variable */ + rtx m; /* multiplicative constant */ + rtx a; /* additive constant */ + rtx reg; /* destination register */ + basic_block before_bb; + rtx before_insn; +{ + rtx seq; - ends_need_computing = 0; - /* For each DEST_REG giv, compute lifetime starts, and try to compute - lifetime ends from regscan info. */ - for (i = 0, v = bl->giv; v; v = v->next_iv) + if (! before_insn) { - if (v->ignore) - continue; - if (v->giv_type == DEST_ADDR) - { - /* Loop unrolling of an inner loop can even create new DEST_REG - givs. */ - rtx p; - for (p = v->insn; INSN_UID (p) >= max_uid_for_loop; ) - p = PREV_INSN (p); - stats[i].start_luid = stats[i].end_luid = INSN_LUID (p); - if (p != v->insn) - stats[i].end_luid++; - } - else /* v->giv_type == DEST_REG */ - { - if (v->last_use) - { - stats[i].start_luid = INSN_LUID (v->insn); - stats[i].end_luid = INSN_LUID (v->last_use); - } - else if (INSN_UID (v->insn) >= max_uid_for_loop) - { - rtx p; - /* This insn has been created by loop optimization on an inner - loop. We don't have a proper start_luid that will match - when we see the first set. But we do know that there will - be no use before the set, so we can set end_luid to 0 so that - we'll start looking for the last use right away. */ - for (p = PREV_INSN (v->insn); INSN_UID (p) >= max_uid_for_loop; ) - p = PREV_INSN (p); - stats[i].start_luid = INSN_LUID (p); - stats[i].end_luid = 0; - ends_need_computing++; - } - else - { - int regno = REGNO (v->dest_reg); - int count = VARRAY_INT (n_times_set, regno) - 1; - rtx p = v->insn; - - /* Find the first insn that sets the giv, so that we can verify - if this giv's lifetime wraps around the loop. We also need - the luid of the first setting insn in order to detect the - last use properly. */ - while (count) - { - p = prev_nonnote_insn (p); - if (reg_set_p (v->dest_reg, p)) - count--; - } - - stats[i].start_luid = INSN_LUID (p); - if (stats[i].start_luid > uid_luid[REGNO_FIRST_UID (regno)]) - { - stats[i].end_luid = -1; - ends_need_computing++; - } - else - { - stats[i].end_luid = uid_luid[REGNO_LAST_UID (regno)]; - if (stats[i].end_luid > INSN_LUID (loop_end)) - { - stats[i].end_luid = -1; - ends_need_computing++; - } - } - } - } - i++; + loop_iv_add_mult_hoist (loop, b, m, a, reg); + return; } - /* If the regscan information was unconclusive for one or more DEST_REG - givs, scan the all insn in the loop to find out lifetime ends. */ - if (ends_need_computing) - { - rtx biv = bl->biv->src_reg; - rtx p = loop_end; + /* Use copy_rtx to prevent unexpected sharing of these rtx. */ + seq = gen_add_mult (copy_rtx (b), m, copy_rtx (a), reg); - do - { - if (p == loop_start) - p = loop_end; - p = PREV_INSN (p); - if (GET_RTX_CLASS (GET_CODE (p)) != 'i') - continue; - ends_need_computing -= find_life_end (PATTERN (p), stats, p, biv); - } - while (ends_need_computing); - } + /* Increase the lifetime of any invariants moved further in code. */ + update_reg_last_use (a, before_insn); + update_reg_last_use (b, before_insn); + update_reg_last_use (m, before_insn); - /* Set start_luid back to the last insn that sets the giv. This allows - more combinations. */ - for (i = 0, v = bl->giv; v; v = v->next_iv) - { - if (v->ignore) - continue; - if (INSN_UID (v->insn) < max_uid_for_loop) - stats[i].start_luid = INSN_LUID (v->insn); - i++; - } + loop_insn_emit_before (loop, before_bb, before_insn, seq); - /* Now adjust lifetime ends by taking combined givs into account. */ - for (i = 0, v = bl->giv; v; v = v->next_iv) - { - unsigned luid; - int j; + /* It is possible that the expansion created lots of new registers. + Iterate over the sequence we just created and record them all. */ + loop_regs_update (loop, seq); +} - if (v->ignore) - continue; - if (v->same && ! v->same->ignore) - { - j = v->same->ix; - luid = stats[i].start_luid; - /* Use unsigned arithmetic to model loop wrap-around. */ - if (luid - stats[j].start_luid - > (unsigned) stats[j].end_luid - stats[j].start_luid) - stats[j].end_luid = luid; - } - i++; - } - qsort (stats, giv_count, sizeof(*stats), cmp_recombine_givs_stats); +/* Emit insns in loop pre-header to set REG = B * M + A. */ - /* Try to derive DEST_REG givs from previous DEST_REG givs with the - same mult_val and non-overlapping lifetime. This reduces register - pressure. - Once we find a DEST_REG giv that is suitable to derive others from, - we set last_giv to this giv, and try to derive as many other DEST_REG - givs from it without joining overlapping lifetimes. If we then - encounter a DEST_REG giv that we can't derive, we set rescan to the - index for this giv (unless rescan is already set). - When we are finished with the current LAST_GIV (i.e. the inner loop - terminates), we start again with rescan, which then becomes the new - LAST_GIV. */ - for (i = giv_count - 1; i >= 0; i = rescan) - { - int life_start, life_end; +void +loop_iv_add_mult_sink (loop, b, m, a, reg) + const struct loop *loop; + rtx b; /* initial value of basic induction variable */ + rtx m; /* multiplicative constant */ + rtx a; /* additive constant */ + rtx reg; /* destination register */ +{ + rtx seq; - for (last_giv = 0, rescan = -1; i >= 0; i--) - { - rtx sum; + /* Use copy_rtx to prevent unexpected sharing of these rtx. */ + seq = gen_add_mult (copy_rtx (b), m, copy_rtx (a), reg); - v = giv_array[stats[i].giv_number]; - if (v->giv_type != DEST_REG || v->derived_from || v->same) - continue; - if (! last_giv) - { - /* Don't use a giv that's likely to be dead to derive - others - that would be likely to keep that giv alive. */ - if (! v->maybe_dead || v->combined_with) - { - last_giv = v; - life_start = stats[i].start_luid; - life_end = stats[i].end_luid; - } - continue; - } - /* Use unsigned arithmetic to model loop wrap around. */ - if (((unsigned) stats[i].start_luid - life_start - >= (unsigned) life_end - life_start) - && ((unsigned) stats[i].end_luid - life_start - > (unsigned) life_end - life_start) - /* Check that the giv insn we're about to use for deriving - precedes all uses of that giv. Note that initializing the - derived giv would defeat the purpose of reducing register - pressure. - ??? We could arrange to move the insn. */ - && ((unsigned) stats[i].end_luid - INSN_LUID (loop_start) - > (unsigned) stats[i].start_luid - INSN_LUID (loop_start)) - && rtx_equal_p (last_giv->mult_val, v->mult_val) - /* ??? Could handle libcalls, but would need more logic. */ - && ! find_reg_note (v->insn, REG_RETVAL, NULL_RTX) - /* We would really like to know if for any giv that v - is combined with, v->insn or any intervening biv increment - dominates that combined giv. However, we - don't have this detailed control flow information. - N.B. since last_giv will be reduced, it is valid - anywhere in the loop, so we don't need to check the - validity of last_giv. - We rely here on the fact that v->always_executed implies that - there is no jump to someplace else in the loop before the - giv insn, and hence any insn that is executed before the - giv insn in the loop will have a lower luid. */ - && (v->always_executed || ! v->combined_with) - && (sum = express_from (last_giv, v)) - /* Make sure we don't make the add more expensive. ADD_COST - doesn't take different costs of registers and constants into - account, so compare the cost of the actual SET_SRCs. */ - && (rtx_cost (sum, SET) - <= rtx_cost (SET_SRC (single_set (v->insn)), SET)) - /* ??? unroll can't understand anything but reg + const_int - sums. It would be cleaner to fix unroll. */ - && ((GET_CODE (sum) == PLUS - && GET_CODE (XEXP (sum, 0)) == REG - && GET_CODE (XEXP (sum, 1)) == CONST_INT) - || ! unroll_p) - && validate_change (v->insn, &PATTERN (v->insn), - gen_rtx_SET (VOIDmode, v->dest_reg, sum), 0)) - { - v->derived_from = last_giv; - life_end = stats[i].end_luid; + /* Increase the lifetime of any invariants moved further in code. + ???? Is this really necessary? */ + update_reg_last_use (a, loop->sink); + update_reg_last_use (b, loop->sink); + update_reg_last_use (m, loop->sink); - if (loop_dump_stream) - { - fprintf (loop_dump_stream, - "giv at %d derived from %d as ", - INSN_UID (v->insn), INSN_UID (last_giv->insn)); - print_rtl (loop_dump_stream, sum); - putc ('\n', loop_dump_stream); - } - } - else if (rescan < 0) - rescan = i; - } - } + loop_insn_sink (loop, seq); + + /* It is possible that the expansion created lots of new registers. + Iterate over the sequence we just created and record them all. */ + loop_regs_update (loop, seq); } - -/* EMIT code before INSERT_BEFORE to set REG = B * M + A. */ + + +/* Emit insns after loop to set REG = B * M + A. */ void -emit_iv_add_mult (b, m, a, reg, insert_before) +loop_iv_add_mult_hoist (loop, b, m, a, reg) + const struct loop *loop; rtx b; /* initial value of basic induction variable */ rtx m; /* multiplicative constant */ rtx a; /* additive constant */ rtx reg; /* destination register */ - rtx insert_before; { rtx seq; - rtx result; - /* Prevent unexpected sharing of these rtx. */ - a = copy_rtx (a); - b = copy_rtx (b); + /* Use copy_rtx to prevent unexpected sharing of these rtx. */ + seq = gen_add_mult (copy_rtx (b), m, copy_rtx (a), reg); - /* Increase the lifetime of any invariants moved further in code. */ - update_reg_last_use (a, insert_before); - update_reg_last_use (b, insert_before); - update_reg_last_use (m, insert_before); + loop_insn_hoist (loop, seq); - start_sequence (); - result = expand_mult_add (b, reg, m, a, GET_MODE (reg), 0); - if (reg != result) - emit_move_insn (reg, result); - seq = gen_sequence (); - end_sequence (); + /* It is possible that the expansion created lots of new registers. + Iterate over the sequence we just created and record them all. */ + loop_regs_update (loop, seq); +} - emit_insn_before (seq, insert_before); - /* It is entirely possible that the expansion created lots of new - registers. Iterate over the sequence we just created and - record them all. */ - if (GET_CODE (seq) == SEQUENCE) +/* Similar to gen_add_mult, but compute cost rather than generating + sequence. */ + +static int +iv_add_mult_cost (b, m, a, reg) + rtx b; /* initial value of basic induction variable */ + rtx m; /* multiplicative constant */ + rtx a; /* additive constant */ + rtx reg; /* destination register */ +{ + int cost = 0; + rtx last, result; + + start_sequence (); + result = expand_mult_add (b, reg, m, a, GET_MODE (reg), 1); + if (reg != result) + emit_move_insn (reg, result); + last = get_last_insn (); + while (last) { - int i; - for (i = 0; i < XVECLEN (seq, 0); ++i) - { - rtx set = single_set (XVECEXP (seq, 0, i)); - if (set && GET_CODE (SET_DEST (set)) == REG) - record_base_value (REGNO (SET_DEST (set)), SET_SRC (set), 0); - } + rtx t = single_set (last); + if (t) + cost += rtx_cost (SET_SRC (t), SET); + last = PREV_INSN (last); } - else if (GET_CODE (seq) == SET - && GET_CODE (SET_DEST (seq)) == REG) - record_base_value (REGNO (SET_DEST (seq)), SET_SRC (seq), 0); + end_sequence (); + return cost; } /* Test whether A * B can be computed without @@ -7612,8 +7761,6 @@ product_cheap_p (a, b) { int i; rtx tmp; - struct obstack *old_rtl_obstack = rtl_obstack; - char *storage = (char *) obstack_alloc (&temp_obstack, 0); int win = 1; /* If only one is constant, make it B. */ @@ -7632,9 +7779,8 @@ product_cheap_p (a, b) code for the multiply and see if a call or multiply, or long sequence of insns is generated. */ - rtl_obstack = &temp_obstack; start_sequence (); - expand_mult (GET_MODE (a), a, b, NULL_RTX, 0); + expand_mult (GET_MODE (a), a, b, NULL_RTX, 1); tmp = gen_sequence (); end_sequence (); @@ -7669,11 +7815,6 @@ product_cheap_p (a, b) && GET_CODE (SET_SRC (XVECEXP (tmp, 0, 0))) == MULT) win = 0; - /* Free any storage we obtained in generating this multiply and restore rtl - allocation to its normal obstack. */ - obstack_free (&temp_obstack, storage); - rtl_obstack = old_rtl_obstack; - return win; } @@ -7693,12 +7834,13 @@ product_cheap_p (a, b) final_[bg]iv_value. */ static int -check_dbra_loop (loop_end, insn_count, loop_start, loop_info) - rtx loop_end; +check_dbra_loop (loop, insn_count) + struct loop *loop; int insn_count; - rtx loop_start; - struct loop_info *loop_info; { + struct loop_info *loop_info = LOOP_INFO (loop); + struct loop_regs *regs = LOOP_REGS (loop); + struct loop_ivs *ivs = LOOP_IVS (loop); struct iv_class *bl; rtx reg; rtx jump_label; @@ -7711,14 +7853,18 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) rtx jump; rtx first_compare; int compare_and_branch; + rtx loop_start = loop->start; + rtx loop_end = loop->end; /* If last insn is a conditional branch, and the insn before tests a register value, try to optimize it. Otherwise, we can't do anything. */ jump = PREV_INSN (loop_end); - comparison = get_condition_for_loop (jump); + comparison = get_condition_for_loop (loop, jump); if (comparison == 0) return 0; + if (!onlyjump_p (jump)) + return 0; /* Try to compute whether the compare/branch at the loop end is one or two instructions. */ @@ -7730,12 +7876,26 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) else return 0; + { + /* If more than one condition is present to control the loop, then + do not proceed, as this function does not know how to rewrite + loop tests with more than one condition. + + Look backwards from the first insn in the last comparison + sequence and see if we've got another comparison sequence. */ + + rtx jump1; + if ((jump1 = prev_nonnote_insn (first_compare)) != loop->cont) + if (GET_CODE (jump1) == JUMP_INSN) + return 0; + } + /* Check all of the bivs to see if the compare uses one of them. Skip biv's set more than once because we can't guarantee that it will be zero on the last iteration. Also skip if the biv is used between its update and the test insn. */ - for (bl = loop_iv_list; bl; bl = bl->next) + for (bl = ivs->list; bl; bl = bl->next) { if (bl->biv_count == 1 && ! bl->biv->maybe_multiple @@ -7770,9 +7930,10 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) % (-INTVAL (bl->biv->add_val))) == 0) { /* register always nonnegative, add REG_NOTE to branch */ - REG_NOTES (PREV_INSN (loop_end)) - = gen_rtx_EXPR_LIST (REG_NONNEG, NULL_RTX, - REG_NOTES (PREV_INSN (loop_end))); + if (! find_reg_note (jump, REG_NONNEG, NULL_RTX)) + REG_NOTES (jump) + = gen_rtx_EXPR_LIST (REG_NONNEG, bl->biv->dest_reg, + REG_NOTES (jump)); bl->nonneg = 1; return 1; @@ -7787,7 +7948,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) if (GET_CODE (p) != JUMP_INSN) continue; - before_comparison = get_condition_for_loop (p); + before_comparison = get_condition_for_loop (loop, p); if (before_comparison && XEXP (before_comparison, 0) == bl->biv->dest_reg && GET_CODE (before_comparison) == LT @@ -7795,9 +7956,10 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) && ! reg_set_between_p (bl->biv->dest_reg, p, loop_start) && INTVAL (bl->biv->add_val) == -1) { - REG_NOTES (PREV_INSN (loop_end)) - = gen_rtx_EXPR_LIST (REG_NONNEG, NULL_RTX, - REG_NOTES (PREV_INSN (loop_end))); + if (! find_reg_note (jump, REG_NONNEG, NULL_RTX)) + REG_NOTES (jump) + = gen_rtx_EXPR_LIST (REG_NONNEG, bl->biv->dest_reg, + REG_NOTES (jump)); bl->nonneg = 1; return 1; @@ -7826,16 +7988,18 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) int reversible_mem_store = 1; if (bl->giv_count == 0 - && ! loop_number_exit_count[uid_loop_num[INSN_UID (loop_start)]]) + && !loop->exit_count + && !loop_info->has_multiple_exit_targets) { rtx bivreg = regno_reg_rtx[bl->regno]; + struct iv_class *blt; /* If there are no givs for this biv, and the only exit is the fall through at the end of the loop, then see if perhaps there are no uses except to count. */ no_use_except_counting = 1; for (p = loop_start; p != loop_end; p = NEXT_INSN (p)) - if (GET_RTX_CLASS (GET_CODE (p)) == 'i') + if (INSN_P (p)) { rtx set = single_set (p); @@ -7851,9 +8015,9 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) that has more than one usage, then the biv has uses other than counting since it's used to derive a value that is used more than one time. */ - note_set_pseudo_multiple_uses_retval = 0; - note_stores (PATTERN (p), note_set_pseudo_multiple_uses); - if (note_set_pseudo_multiple_uses_retval) + note_stores (PATTERN (p), note_set_pseudo_multiple_uses, + regs); + if (regs->multiple_uses) { no_use_except_counting = 0; break; @@ -7865,15 +8029,26 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) break; } } + + /* A biv has uses besides counting if it is used to set + another biv. */ + for (blt = ivs->list; blt; blt = blt->next) + if (blt->init_set + && reg_mentioned_p (bivreg, SET_SRC (blt->init_set))) + { + no_use_except_counting = 0; + break; + } } if (no_use_except_counting) - ; /* no need to worry about MEMs. */ - else if (num_mem_sets <= 1) + /* No need to worry about MEMs. */ + ; + else if (loop_info->num_mem_sets <= 1) { for (p = loop_start; p != loop_end; p = NEXT_INSN (p)) - if (GET_RTX_CLASS (GET_CODE (p)) == 'i') - num_nonfixed_reads += count_nonfixed_reads (PATTERN (p)); + if (INSN_P (p)) + num_nonfixed_reads += count_nonfixed_reads (loop, PATTERN (p)); /* If the loop has a single store, and the destination address is invariant, then we can't reverse the loop, because this address @@ -7881,13 +8056,15 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) This would work if the source was invariant also, however, in that case, the insn should have been moved out of the loop. */ - if (num_mem_sets == 1) + if (loop_info->num_mem_sets == 1) { struct induction *v; - reversible_mem_store - = (! unknown_address_altered - && ! invariant_p (XEXP (XEXP (loop_store_mems, 0), 0))); + /* If we could prove that each of the memory locations + written to was different, then we could reverse the + store -- but we don't presently have any way of + knowing that. */ + reversible_mem_store = 0; /* If the store depends on a register that is set after the store, it depends on the initial value, and is thus not @@ -7896,8 +8073,9 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) { if (v->giv_type == DEST_REG && reg_mentioned_p (v->dest_reg, - PATTERN (first_loop_store_insn)) - && loop_insn_first_p (first_loop_store_insn, v->insn)) + PATTERN (loop_info->first_loop_store_insn)) + && loop_insn_first_p (loop_info->first_loop_store_insn, + v->insn)) reversible_mem_store = 0; } } @@ -7914,12 +8092,12 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) about all these things. */ if ((num_nonfixed_reads <= 1 - && !loop_has_call - && !loop_has_volatile + && ! loop_info->has_nonconst_call + && ! loop_info->has_volatile && reversible_mem_store - && (bl->giv_count + bl->biv_count + num_mem_sets - + num_movables + compare_and_branch == insn_count) - && (bl == loop_iv_list && bl->next == 0)) + && (bl->giv_count + bl->biv_count + loop_info->num_mem_sets + + num_unmoved_movables (loop) + compare_and_branch == insn_count) + && (bl == ivs->list && bl->next == 0)) || no_use_except_counting) { rtx tem; @@ -7931,7 +8109,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* Now check other conditions: The increment must be a constant, as must the initial value, - and the comparison code must be LT. + and the comparison code must be LT. This test can probably be improved since +/- 1 in the constant can be obtained by changing LT to LE and vice versa; this is @@ -7943,7 +8121,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) || (GET_CODE (comparison) == LE && no_use_except_counting))) { - HOST_WIDE_INT add_val, add_adjust, comparison_val; + HOST_WIDE_INT add_val, add_adjust, comparison_val = 0; rtx initial_value, comparison_value; int nonneg = 0; enum rtx_code cmp_code; @@ -7961,7 +8139,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) if (comparison_const_width > HOST_BITS_PER_WIDE_INT) comparison_const_width = HOST_BITS_PER_WIDE_INT; comparison_sign_mask - = (unsigned HOST_WIDE_INT)1 << (comparison_const_width - 1); + = (unsigned HOST_WIDE_INT) 1 << (comparison_const_width - 1); /* If the comparison value is not a loop invariant, then we can not reverse this loop. @@ -7969,14 +8147,14 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) ??? If the insns which initialize the comparison value as a whole compute an invariant result, then we could move them out of the loop and proceed with loop reversal. */ - if (!invariant_p (comparison_value)) + if (! loop_invariant_p (loop, comparison_value)) return 0; if (GET_CODE (comparison_value) == CONST_INT) comparison_val = INTVAL (comparison_value); initial_value = bl->initial_value; - - /* Normalize the initial value if it is an integer and + + /* Normalize the initial value if it is an integer and has no other use except as a counter. This will allow a few more loops to be reversed. */ if (no_use_except_counting @@ -8001,13 +8179,14 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* First check if we can do a vanilla loop reversal. */ if (initial_value == const0_rtx - /* If we have a decrement_and_branch_on_count, prefer - the NE test, since this will allow that instruction to - be generated. Note that we must use a vanilla loop - reversal if the biv is used to calculate a giv or has - a non-counting use. */ -#if ! defined (HAVE_decrement_and_branch_until_zero) && defined (HAVE_decrement_and_branch_on_count) - && (! (add_val == 1 && loop_info->vtop + /* If we have a decrement_and_branch_on_count, + prefer the NE test, since this will allow that + instruction to be generated. Note that we must + use a vanilla loop reversal if the biv is used to + calculate a giv or has a non-counting use. */ +#if ! defined (HAVE_decrement_and_branch_until_zero) \ +&& defined (HAVE_decrement_and_branch_on_count) + && (! (add_val == 1 && loop->vtop && (bl->biv_count == 0 || no_use_except_counting))) #endif @@ -8022,7 +8201,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) nonneg = 1; cmp_code = GE; } - else if (add_val == 1 && loop_info->vtop + else if (add_val == 1 && loop->vtop && (bl->biv_count == 0 || no_use_except_counting)) { @@ -8065,10 +8244,8 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* Save some info needed to produce the new insns. */ reg = bl->biv->dest_reg; - jump_label = XEXP (SET_SRC (PATTERN (PREV_INSN (loop_end))), 1); - if (jump_label == pc_rtx) - jump_label = XEXP (SET_SRC (PATTERN (PREV_INSN (loop_end))), 2); - new_add_val = GEN_INT (- INTVAL (bl->biv->add_val)); + jump_label = condjump_label (PREV_INSN (loop_end)); + new_add_val = GEN_INT (-INTVAL (bl->biv->add_val)); /* Set start_value; if this is not a CONST_INT, we need to generate a SUB. @@ -8079,25 +8256,20 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) && GET_CODE (comparison_value) == CONST_INT) { start_value = GEN_INT (comparison_val - add_adjust); - emit_insn_before (gen_move_insn (reg, start_value), - loop_start); + loop_insn_hoist (loop, gen_move_insn (reg, start_value)); } else if (GET_CODE (initial_value) == CONST_INT) { - rtx offset = GEN_INT (-INTVAL (initial_value) - add_adjust); enum machine_mode mode = GET_MODE (reg); - enum insn_code icode - = add_optab->handlers[(int) mode].insn_code; - if (! (*insn_operand_predicate[icode][0]) (reg, mode) - || ! ((*insn_operand_predicate[icode][1]) - (comparison_value, mode)) - || ! (*insn_operand_predicate[icode][2]) (offset, mode)) + rtx offset = GEN_INT (-INTVAL (initial_value) - add_adjust); + rtx add_insn = gen_add3_insn (reg, comparison_value, offset); + + if (add_insn == 0) return 0; + start_value = gen_rtx_PLUS (mode, comparison_value, offset); - emit_insn_before ((GEN_FCN (icode) - (reg, comparison_value, offset)), - loop_start); + loop_insn_hoist (loop, add_insn); if (GET_CODE (comparison) == LE) final_value = gen_rtx_PLUS (mode, comparison_value, GEN_INT (add_val)); @@ -8105,19 +8277,14 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) else if (! add_adjust) { enum machine_mode mode = GET_MODE (reg); - enum insn_code icode - = sub_optab->handlers[(int) mode].insn_code; - if (! (*insn_operand_predicate[icode][0]) (reg, mode) - || ! ((*insn_operand_predicate[icode][1]) - (comparison_value, mode)) - || ! ((*insn_operand_predicate[icode][2]) - (initial_value, mode))) + rtx sub_insn = gen_sub3_insn (reg, comparison_value, + initial_value); + + if (sub_insn == 0) return 0; start_value = gen_rtx_MINUS (mode, comparison_value, initial_value); - emit_insn_before ((GEN_FCN (icode) - (reg, comparison_value, initial_value)), - loop_start); + loop_insn_hoist (loop, sub_insn); } else /* We could handle the other cases too, but it'll be @@ -8128,12 +8295,12 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) create a sequence to hold all the insns from expand_inc. */ start_sequence (); expand_inc (reg, new_add_val); - tem = gen_sequence (); - end_sequence (); + tem = gen_sequence (); + end_sequence (); - p = emit_insn_before (tem, bl->biv->insn); + p = loop_insn_emit_before (loop, 0, bl->biv->insn, tem); delete_insn (bl->biv->insn); - + /* Update biv info to reflect its new status. */ bl->biv->insn = p; bl->initial_value = start_value; @@ -8150,25 +8317,24 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* Inc LABEL_NUSES so that delete_insn will not delete the label. */ - LABEL_NUSES (XEXP (jump_label, 0)) ++; + LABEL_NUSES (XEXP (jump_label, 0))++; /* Emit an insn after the end of the loop to set the biv's proper exit value if it is used anywhere outside the loop. */ if ((REGNO_LAST_UID (bl->regno) != INSN_UID (first_compare)) || ! bl->init_insn || REGNO_FIRST_UID (bl->regno) != INSN_UID (bl->init_insn)) - emit_insn_after (gen_move_insn (reg, final_value), - loop_end); + loop_insn_sink (loop, gen_move_insn (reg, final_value)); /* Delete compare/branch at end of loop. */ - delete_insn (PREV_INSN (loop_end)); + delete_related_insns (PREV_INSN (loop_end)); if (compare_and_branch == 2) - delete_insn (first_compare); + delete_related_insns (first_compare); /* Add new compare/branch insn at end of loop. */ start_sequence (); emit_cmp_and_jump_insns (reg, const0_rtx, cmp_code, NULL_RTX, - GET_MODE (reg), 0, 0, + GET_MODE (reg), 0, XEXP (jump_label, 0)); tem = gen_sequence (); end_sequence (); @@ -8189,7 +8355,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* Increment of LABEL_NUSES done above. */ /* Register is now always nonnegative, so add REG_NONNEG note to the branch. */ - REG_NOTES (tem) = gen_rtx_EXPR_LIST (REG_NONNEG, NULL_RTX, + REG_NOTES (tem) = gen_rtx_EXPR_LIST (REG_NONNEG, reg, REG_NOTES (tem)); } bl->nonneg = 1; @@ -8207,7 +8373,7 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) remove all REG_EQUAL notes based on the reversed biv here. */ for (p = loop_start; p != loop_end; p = NEXT_INSN (p)) - if (GET_RTX_CLASS (GET_CODE (p)) == 'i') + if (INSN_P (p)) { rtx *pnote; rtx set = single_set (p); @@ -8215,9 +8381,9 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) REG_EQUAL notes should still be correct. */ if (! set || GET_CODE (SET_DEST (set)) != REG - || (size_t) REGNO (SET_DEST (set)) >= reg_iv_type->num_elements - || REG_IV_TYPE (REGNO (SET_DEST (set))) != GENERAL_INDUCT - || REG_IV_INFO (REGNO (SET_DEST (set)))->src_reg != bl->biv->src_reg) + || (size_t) REGNO (SET_DEST (set)) >= ivs->n_regs + || REG_IV_TYPE (ivs, REGNO (SET_DEST (set))) != GENERAL_INDUCT + || REG_IV_INFO (ivs, REGNO (SET_DEST (set)))->src_reg != bl->biv->src_reg) for (pnote = ®_NOTES (p); *pnote;) { if (REG_NOTE_KIND (*pnote) == REG_EQUAL @@ -8254,7 +8420,6 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) /* Verify whether the biv BL appears to be eliminable, based on the insns in the loop that refer to it. - LOOP_START is the first insn of the loop, and END is the end insn. If ELIMINATE_P is non-zero, actually do the elimination. @@ -8263,23 +8428,24 @@ check_dbra_loop (loop_end, insn_count, loop_start, loop_info) start of the loop. */ static int -maybe_eliminate_biv (bl, loop_start, end, eliminate_p, threshold, insn_count) +maybe_eliminate_biv (loop, bl, eliminate_p, threshold, insn_count) + const struct loop *loop; struct iv_class *bl; - rtx loop_start; - rtx end; int eliminate_p; int threshold, insn_count; { + struct loop_ivs *ivs = LOOP_IVS (loop); rtx reg = bl->biv->dest_reg; rtx p; /* Scan all insns in the loop, stopping if we find one that uses the biv in a way that we cannot eliminate. */ - for (p = loop_start; p != end; p = NEXT_INSN (p)) + for (p = loop->start; p != loop->end; p = NEXT_INSN (p)) { enum rtx_code code = GET_CODE (p); - rtx where = threshold >= insn_count ? loop_start : p; + basic_block where_bb = 0; + rtx where_insn = threshold >= insn_count ? 0 : p; /* If this is a libcall that sets a giv, skip ahead to its end. */ if (GET_RTX_CLASS (code) == 'i') @@ -8293,18 +8459,19 @@ maybe_eliminate_biv (bl, loop_start, end, eliminate_p, threshold, insn_count) if (set && GET_CODE (SET_DEST (set)) == REG) { - int regno = REGNO (SET_DEST (set)); + unsigned int regno = REGNO (SET_DEST (set)); - if (regno < max_reg_before_loop - && REG_IV_TYPE (regno) == GENERAL_INDUCT - && REG_IV_INFO (regno)->src_reg == bl->biv->src_reg) + if (regno < ivs->n_regs + && REG_IV_TYPE (ivs, regno) == GENERAL_INDUCT + && REG_IV_INFO (ivs, regno)->src_reg == bl->biv->src_reg) p = last; } } } if ((code == INSN || code == JUMP_INSN || code == CALL_INSN) && reg_mentioned_p (reg, PATTERN (p)) - && ! maybe_eliminate_biv_1 (PATTERN (p), p, bl, eliminate_p, where)) + && ! maybe_eliminate_biv_1 (loop, PATTERN (p), p, bl, + eliminate_p, where_bb, where_insn)) { if (loop_dump_stream) fprintf (loop_dump_stream, @@ -8314,7 +8481,7 @@ maybe_eliminate_biv (bl, loop_start, end, eliminate_p, threshold, insn_count) } } - if (p == end) + if (p == loop->end) { if (loop_dump_stream) fprintf (loop_dump_stream, "biv %d %s eliminated.\n", @@ -8334,7 +8501,7 @@ loop_insn_first_p (insn, reference) { rtx p, q; - for (p = insn, q = reference; ;) + for (p = insn, q = reference;;) { /* Start with test for not first so that INSN == REFERENCE yields not first. */ @@ -8378,22 +8545,6 @@ biv_elimination_giv_has_0_offset (biv, giv, insn) && loop_insn_first_p (insn, giv->insn)))) return 0; - /* If the giv V was derived from another giv, and INSN does - not occur between the giv insn and the biv insn, then we'd - have to adjust the value used here. This is rare, so we don't - bother to make this possible. */ - if (giv->derived_from - && ! (giv->always_executed - && loop_insn_first_p (giv->insn, insn) - && loop_insn_first_p (insn, biv->insn))) - return 0; - if (giv->same - && giv->same->derived_from - && ! (giv->same->always_executed - && loop_insn_first_p (giv->same->insn, insn) - && loop_insn_first_p (insn, biv->insn))) - return 0; - return 1; } @@ -8402,17 +8553,20 @@ biv_elimination_giv_has_0_offset (biv, giv, insn) If BIV does not appear in X, return 1. - If ELIMINATE_P is non-zero, actually do the elimination. WHERE indicates - where extra insns should be added. Depending on how many items have been - moved out of the loop, it will either be before INSN or at the start of - the loop. */ + If ELIMINATE_P is non-zero, actually do the elimination. + WHERE_INSN/WHERE_BB indicate where extra insns should be added. + Depending on how many items have been moved out of the loop, it + will either be before INSN (when WHERE_INSN is non-zero) or at the + start of the loop (when WHERE_INSN is zero). */ static int -maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) +maybe_eliminate_biv_1 (loop, x, insn, bl, eliminate_p, where_bb, where_insn) + const struct loop *loop; rtx x, insn; struct iv_class *bl; int eliminate_p; - rtx where; + basic_block where_bb; + rtx where_insn; { enum rtx_code code = GET_CODE (x); rtx reg = bl->biv->dest_reg; @@ -8423,7 +8577,7 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) rtx new; #endif int arg_operand; - char *fmt; + const char *fmt; int i, j; switch (code) @@ -8456,7 +8610,7 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) overflows. */ for (v = bl->giv; v; v = v->next_iv) - if (CONSTANT_P (v->mult_val) && v->mult_val != const0_rtx + if (GET_CODE (v->mult_val) == CONST_INT && v->mult_val != const0_rtx && v->add_val == const0_rtx && ! v->ignore && ! v->maybe_dead && v->always_computable && v->mode == mode @@ -8488,14 +8642,15 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) overflow problem. */ for (v = bl->giv; v; v = v->next_iv) - if (CONSTANT_P (v->mult_val) && v->mult_val != const0_rtx + if (GET_CODE (v->mult_val) == CONST_INT + && v->mult_val != const0_rtx && ! v->ignore && ! v->maybe_dead && v->always_computable && v->mode == mode && (GET_CODE (v->add_val) == SYMBOL_REF || GET_CODE (v->add_val) == LABEL_REF || GET_CODE (v->add_val) == CONST || (GET_CODE (v->add_val) == REG - && REGNO_POINTER_FLAG (REGNO (v->add_val))))) + && REG_POINTER (v->add_val)))) { if (! biv_elimination_giv_has_0_offset (bl->biv, v, insn)) continue; @@ -8521,11 +8676,12 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) into a register (it will be a loop invariant.) */ tem = gen_reg_rtx (GET_MODE (v->new_reg)); - emit_insn_before (gen_move_insn (tem, copy_rtx (v->add_val)), - where); + loop_insn_emit_before (loop, 0, where_insn, + gen_move_insn (tem, + copy_rtx (v->add_val))); /* Substitute the new register for its invariant value in - the compare expression. */ + the compare expression. */ XEXP (new, (INTVAL (v->mult_val) < 0) ? 0 : 1) = tem; if (validate_change (insn, &SET_SRC (PATTERN (insn)), new, 0)) return 1; @@ -8553,12 +8709,13 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) negative mult_val, but it seems complex to do it in general. */ for (v = bl->giv; v; v = v->next_iv) - if (CONSTANT_P (v->mult_val) && INTVAL (v->mult_val) > 0 + if (GET_CODE (v->mult_val) == CONST_INT + && INTVAL (v->mult_val) > 0 && (GET_CODE (v->add_val) == SYMBOL_REF || GET_CODE (v->add_val) == LABEL_REF || GET_CODE (v->add_val) == CONST || (GET_CODE (v->add_val) == REG - && REGNO_POINTER_FLAG (REGNO (v->add_val)))) + && REG_POINTER (v->add_val))) && ! v->ignore && ! v->maybe_dead && v->always_computable && v->mode == mode) { @@ -8569,36 +8726,40 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) return 1; /* Replace biv with the giv's reduced reg. */ - XEXP (x, 1-arg_operand) = v->new_reg; + validate_change (insn, &XEXP (x, 1 - arg_operand), v->new_reg, 1); /* If all constants are actually constant integers and the derived constant can be directly placed in the COMPARE, do so. */ if (GET_CODE (arg) == CONST_INT && GET_CODE (v->mult_val) == CONST_INT - && GET_CODE (v->add_val) == CONST_INT - && validate_change (insn, &XEXP (x, arg_operand), - GEN_INT (INTVAL (arg) - * INTVAL (v->mult_val) - + INTVAL (v->add_val)), 0)) - return 1; - - /* Otherwise, load it into a register. */ - tem = gen_reg_rtx (mode); - emit_iv_add_mult (arg, v->mult_val, v->add_val, tem, where); - if (validate_change (insn, &XEXP (x, arg_operand), tem, 0)) + && GET_CODE (v->add_val) == CONST_INT) + { + validate_change (insn, &XEXP (x, arg_operand), + GEN_INT (INTVAL (arg) + * INTVAL (v->mult_val) + + INTVAL (v->add_val)), 1); + } + else + { + /* Otherwise, load it into a register. */ + tem = gen_reg_rtx (mode); + loop_iv_add_mult_emit_before (loop, arg, + v->mult_val, v->add_val, + tem, where_bb, where_insn); + validate_change (insn, &XEXP (x, arg_operand), tem, 1); + } + if (apply_change_group ()) return 1; - - /* If that failed, put back the change we made above. */ - XEXP (x, 1-arg_operand) = reg; } - + /* Look for giv with positive constant mult_val and nonconst add_val. - Insert insns to calculate new compare value. + Insert insns to calculate new compare value. ??? Turn this off due to possible overflow. */ for (v = bl->giv; v; v = v->next_iv) - if (CONSTANT_P (v->mult_val) && INTVAL (v->mult_val) > 0 + if (GET_CODE (v->mult_val) == CONST_INT + && INTVAL (v->mult_val) > 0 && ! v->ignore && ! v->maybe_dead && v->always_computable && v->mode == mode && 0) @@ -8618,7 +8779,9 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) v->new_reg, 1); /* Compute value to compare against. */ - emit_iv_add_mult (arg, v->mult_val, v->add_val, tem, where); + loop_iv_add_mult_emit_before (loop, arg, + v->mult_val, v->add_val, + tem, where_bb, where_insn); /* Use it in this insn. */ validate_change (insn, &XEXP (x, arg_operand), tem, 1); if (apply_change_group ()) @@ -8627,14 +8790,14 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) } else if (GET_CODE (arg) == REG || GET_CODE (arg) == MEM) { - if (invariant_p (arg) == 1) + if (loop_invariant_p (loop, arg) == 1) { /* Look for giv with constant positive mult_val and nonconst - add_val. Insert insns to compute new compare value. + add_val. Insert insns to compute new compare value. ??? Turn this off due to possible overflow. */ for (v = bl->giv; v; v = v->next_iv) - if (CONSTANT_P (v->mult_val) && INTVAL (v->mult_val) > 0 + if (GET_CODE (v->mult_val) == CONST_INT && INTVAL (v->mult_val) > 0 && ! v->ignore && ! v->maybe_dead && v->always_computable && v->mode == mode && 0) @@ -8654,8 +8817,9 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) v->new_reg, 1); /* Compute value to compare against. */ - emit_iv_add_mult (arg, v->mult_val, v->add_val, - tem, where); + loop_iv_add_mult_emit_before (loop, arg, + v->mult_val, v->add_val, + tem, where_bb, where_insn); validate_change (insn, &XEXP (x, arg_operand), tem, 1); if (apply_change_group ()) return 1; @@ -8677,7 +8841,7 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) #if 0 /* Otherwise the reg compared with had better be a biv. */ if (GET_CODE (arg) != REG - || REG_IV_TYPE (REGNO (arg)) != BASIC_INDUCT) + || REG_IV_TYPE (ivs, REGNO (arg)) != BASIC_INDUCT) return 0; /* Look for a pair of givs, one for each biv, @@ -8689,7 +8853,8 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) if (v->ignore || v->maybe_dead || v->mode != mode) continue; - for (tv = reg_biv_class[REGNO (arg)]->giv; tv; tv = tv->next_iv) + for (tv = REG_IV_CLASS (ivs, REGNO (arg))->giv; tv; + tv = tv->next_iv) if (! tv->ignore && ! tv->maybe_dead && rtx_equal_p (tv->mult_val, v->mult_val) && rtx_equal_p (tv->add_val, v->add_val) @@ -8702,7 +8867,7 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) return 1; /* Replace biv with its giv's reduced reg. */ - XEXP (x, 1-arg_operand) = v->new_reg; + XEXP (x, 1 - arg_operand) = v->new_reg; /* Replace other operand with the other giv's reduced reg. */ XEXP (x, arg_operand) = tv->new_reg; @@ -8734,22 +8899,22 @@ maybe_eliminate_biv_1 (x, insn, bl, eliminate_p, where) switch (fmt[i]) { case 'e': - if (! maybe_eliminate_biv_1 (XEXP (x, i), insn, bl, - eliminate_p, where)) + if (! maybe_eliminate_biv_1 (loop, XEXP (x, i), insn, bl, + eliminate_p, where_bb, where_insn)) return 0; break; case 'E': for (j = XVECLEN (x, i) - 1; j >= 0; j--) - if (! maybe_eliminate_biv_1 (XVECEXP (x, i, j), insn, bl, - eliminate_p, where)) + if (! maybe_eliminate_biv_1 (loop, XVECEXP (x, i, j), insn, bl, + eliminate_p, where_bb, where_insn)) return 0; break; } } return 1; -} +} /* Return nonzero if the last use of REG is in an insn following INSN in the same basic block. */ @@ -8774,18 +8939,20 @@ last_use_this_basic_block (reg, insn) just record the location of the set and process it later. */ static void -record_initial (dest, set) +record_initial (dest, set, data) rtx dest; rtx set; + void *data ATTRIBUTE_UNUSED; { + struct loop_ivs *ivs = (struct loop_ivs *) data; struct iv_class *bl; if (GET_CODE (dest) != REG - || REGNO (dest) >= max_reg_before_loop - || REG_IV_TYPE (REGNO (dest)) != BASIC_INDUCT) + || REGNO (dest) >= ivs->n_regs + || REG_IV_TYPE (ivs, REGNO (dest)) != BASIC_INDUCT) return; - bl = reg_biv_class[REGNO (dest)]; + bl = REG_IV_CLASS (ivs, REGNO (dest)); /* If this is the first set found, record it. */ if (bl->init_insn == 0) @@ -8798,7 +8965,7 @@ record_initial (dest, set) /* If any of the registers in X are "old" and currently have a last use earlier than INSN, update them to have a last use of INSN. Their actual last use will be the previous insn but it will not have a valid uid_luid so we can't - use it. */ + use it. X must be a source expression only. */ static void update_reg_last_use (x, insn) @@ -8808,15 +8975,19 @@ update_reg_last_use (x, insn) /* Check for the case where INSN does not have a valid luid. In this case, there is no need to modify the regno_last_uid, as this can only happen when code is inserted after the loop_end to set a pseudo's final value, - and hence this insn will never be the last use of x. */ + and hence this insn will never be the last use of x. + ???? This comment is not correct. See for example loop_givs_reduce. + This may insert an insn before another new insn. */ if (GET_CODE (x) == REG && REGNO (x) < max_reg_before_loop && INSN_UID (insn) < max_uid_for_loop - && uid_luid[REGNO_LAST_UID (REGNO (x))] < uid_luid[INSN_UID (insn)]) - REGNO_LAST_UID (REGNO (x)) = INSN_UID (insn); + && REGNO_LAST_LUID (REGNO (x)) < INSN_LUID (insn)) + { + REGNO_LAST_UID (REGNO (x)) = INSN_UID (insn); + } else { - register int i, j; - register char *fmt = GET_RTX_FORMAT (GET_CODE (x)); + int i, j; + const char *fmt = GET_RTX_FORMAT (GET_CODE (x)); for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--) { if (fmt[i] == 'e') @@ -8828,64 +8999,66 @@ update_reg_last_use (x, insn) } } -/* Given a jump insn JUMP, return the condition that will cause it to branch - to its JUMP_LABEL. If the condition cannot be understood, or is an - inequality floating-point comparison which needs to be reversed, 0 will - be returned. +/* Given an insn INSN and condition COND, return the condition in a + canonical form to simplify testing by callers. Specifically: + + (1) The code will always be a comparison operation (EQ, NE, GT, etc.). + (2) Both operands will be machine operands; (cc0) will have been replaced. + (3) If an operand is a constant, it will be the second operand. + (4) (LE x const) will be replaced with (LT x <const+1>) and similarly + for GE, GEU, and LEU. + + If the condition cannot be understood, or is an inequality floating-point + comparison which needs to be reversed, 0 will be returned. + + If REVERSE is non-zero, then reverse the condition prior to canonizing it. If EARLIEST is non-zero, it is a pointer to a place where the earliest insn used in locating the condition was found. If a replacement test of the condition is desired, it should be placed in front of that insn and we will be sure that the inputs are still valid. - The condition will be returned in a canonical form to simplify testing by - callers. Specifically: - - (1) The code will always be a comparison operation (EQ, NE, GT, etc.). - (2) Both operands will be machine operands; (cc0) will have been replaced. - (3) If an operand is a constant, it will be the second operand. - (4) (LE x const) will be replaced with (LT x <const+1>) and similarly - for GE, GEU, and LEU. */ + If WANT_REG is non-zero, we wish the condition to be relative to that + register, if possible. Therefore, do not canonicalize the condition + further. */ rtx -get_condition (jump, earliest) - rtx jump; +canonicalize_condition (insn, cond, reverse, earliest, want_reg) + rtx insn; + rtx cond; + int reverse; rtx *earliest; + rtx want_reg; { enum rtx_code code; - rtx prev = jump; + rtx prev = insn; rtx set; rtx tem; rtx op0, op1; int reverse_code = 0; - int did_reverse_condition = 0; enum machine_mode mode; - /* If this is not a standard conditional jump, we can't parse it. */ - if (GET_CODE (jump) != JUMP_INSN - || ! condjump_p (jump) || simplejump_p (jump)) - return 0; + code = GET_CODE (cond); + mode = GET_MODE (cond); + op0 = XEXP (cond, 0); + op1 = XEXP (cond, 1); - code = GET_CODE (XEXP (SET_SRC (PATTERN (jump)), 0)); - mode = GET_MODE (XEXP (SET_SRC (PATTERN (jump)), 0)); - op0 = XEXP (XEXP (SET_SRC (PATTERN (jump)), 0), 0); - op1 = XEXP (XEXP (SET_SRC (PATTERN (jump)), 0), 1); + if (reverse) + code = reversed_comparison_code (cond, insn); + if (code == UNKNOWN) + return 0; if (earliest) - *earliest = jump; - - /* If this branches to JUMP_LABEL when the condition is false, reverse - the condition. */ - if (GET_CODE (XEXP (SET_SRC (PATTERN (jump)), 2)) == LABEL_REF - && XEXP (XEXP (SET_SRC (PATTERN (jump)), 2), 0) == JUMP_LABEL (jump)) - code = reverse_condition (code), did_reverse_condition ^= 1; + *earliest = insn; /* If we are comparing a register with zero, see if the register is set in the previous insn to a COMPARE or a comparison operation. Perform the same tests as a function of STORE_FLAG_VALUE as find_comparison_args in cse.c */ - while (GET_RTX_CLASS (code) == '<' && op1 == CONST0_RTX (GET_MODE (op0))) + while (GET_RTX_CLASS (code) == '<' + && op1 == CONST0_RTX (GET_MODE (op0)) + && op0 != want_reg) { /* Set non-zero when we find something of interest. */ rtx x = 0; @@ -8924,15 +9097,21 @@ get_condition (jump, earliest) if ((prev = prev_nonnote_insn (prev)) == 0 || GET_CODE (prev) != INSN - || FIND_REG_INC_NOTE (prev, 0) - || (set = single_set (prev)) == 0) + || FIND_REG_INC_NOTE (prev, NULL_RTX)) + break; + + set = set_of (op0, prev); + + if (set + && (GET_CODE (set) != SET + || !rtx_equal_p (SET_DEST (set), op0))) break; /* If this is setting OP0, get what it sets it to if it looks relevant. */ - if (rtx_equal_p (SET_DEST (set), op0)) + if (set) { - enum machine_mode inner_mode = GET_MODE (SET_SRC (set)); + enum machine_mode inner_mode = GET_MODE (SET_DEST (set)); /* ??? We may not combine comparisons done in a CCmode with comparisons not done in a CCmode. This is to aid targets @@ -8960,7 +9139,8 @@ get_condition (jump, earliest) #ifdef FLOAT_STORE_FLAG_VALUE || (code == LT && GET_MODE_CLASS (inner_mode) == MODE_FLOAT - && FLOAT_STORE_FLAG_VALUE < 0) + && (REAL_VALUE_NEGATIVE + (FLOAT_STORE_FLAG_VALUE (inner_mode)))) #endif )) && GET_RTX_CLASS (GET_CODE (SET_SRC (set))) == '<')) @@ -8979,19 +9159,16 @@ get_condition (jump, earliest) #ifdef FLOAT_STORE_FLAG_VALUE || (code == GE && GET_MODE_CLASS (inner_mode) == MODE_FLOAT - && FLOAT_STORE_FLAG_VALUE < 0) + && (REAL_VALUE_NEGATIVE + (FLOAT_STORE_FLAG_VALUE (inner_mode)))) #endif )) && GET_RTX_CLASS (GET_CODE (SET_SRC (set))) == '<' - && (((GET_MODE_CLASS (mode) == MODE_CC) + && (((GET_MODE_CLASS (mode) == MODE_CC) == (GET_MODE_CLASS (inner_mode) == MODE_CC)) || mode == VOIDmode || inner_mode == VOIDmode)) { - /* We might have reversed a LT to get a GE here. But this wasn't - actually the comparison of data, so we don't flag that we - have had to reverse the condition. */ - did_reverse_condition ^= 1; reverse_code = 1; x = SET_SRC (set); } @@ -9009,8 +9186,9 @@ get_condition (jump, earliest) code = GET_CODE (x); if (reverse_code) { - code = reverse_condition (code); - did_reverse_condition ^= 1; + code = reversed_comparison_code (x, prev); + if (code == UNKNOWN) + return 0; reverse_code = 0; } @@ -9046,7 +9224,7 @@ get_condition (jump, earliest) { case LE: if ((unsigned HOST_WIDE_INT) const_val != max_val >> 1) - code = LT, op1 = GEN_INT (const_val + 1); + code = LT, op1 = GEN_INT (const_val + 1); break; /* When cross-compiling, const_val might be sign-extended from @@ -9073,14 +9251,6 @@ get_condition (jump, earliest) } } - /* If this was floating-point and we reversed anything other than an - EQ or NE, return zero. */ - if (TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT - && did_reverse_condition && code != NE && code != EQ - && ! flag_fast_math - && GET_MODE_CLASS (GET_MODE (op0)) == MODE_FLOAT) - return 0; - #ifdef HAVE_cc0 /* Never return CC0; return zero instead. */ if (op0 == cc0_rtx) @@ -9090,310 +9260,60 @@ get_condition (jump, earliest) return gen_rtx_fmt_ee (code, VOIDmode, op0, op1); } -/* Similar to above routine, except that we also put an invariant last - unless both operands are invariants. */ - -rtx -get_condition_for_loop (x) - rtx x; -{ - rtx comparison = get_condition (x, NULL_PTR); - - if (comparison == 0 - || ! invariant_p (XEXP (comparison, 0)) - || invariant_p (XEXP (comparison, 1))) - return comparison; - - return gen_rtx_fmt_ee (swap_condition (GET_CODE (comparison)), VOIDmode, - XEXP (comparison, 1), XEXP (comparison, 0)); -} +/* Given a jump insn JUMP, return the condition that will cause it to branch + to its JUMP_LABEL. If the condition cannot be understood, or is an + inequality floating-point comparison which needs to be reversed, 0 will + be returned. -#ifdef HAVE_decrement_and_branch_on_count -/* Instrument loop for insertion of bct instruction. We distinguish between - loops with compile-time bounds and those with run-time bounds. - Information from loop_iterations() is used to compute compile-time bounds. - Run-time bounds should use loop preconditioning, but currently ignored. - */ + If EARLIEST is non-zero, it is a pointer to a place where the earliest + insn used in locating the condition was found. If a replacement test + of the condition is desired, it should be placed in front of that + insn and we will be sure that the inputs are still valid. */ -static void -insert_bct (loop_start, loop_end, loop_info) - rtx loop_start, loop_end; - struct loop_info *loop_info; +rtx +get_condition (jump, earliest) + rtx jump; + rtx *earliest; { - int i; - unsigned HOST_WIDE_INT n_iterations; - - int increment_direction, compare_direction; - - /* If the loop condition is <= or >=, the number of iteration - is 1 more than the range of the bounds of the loop. */ - int add_iteration = 0; - - enum machine_mode loop_var_mode = word_mode; - - int loop_num = uid_loop_num [INSN_UID (loop_start)]; - - /* It's impossible to instrument a competely unrolled loop. */ - if (loop_info->unroll_number == -1) - return; - - /* Make sure that the count register is not in use. */ - if (loop_used_count_register [loop_num]) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT instrumentation failed: count register already in use\n", - loop_num); - return; - } - - /* Make sure that the function has no indirect jumps. */ - if (indirect_jump_in_function) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT instrumentation failed: indirect jump in function\n", - loop_num); - return; - } - - /* Make sure that the last loop insn is a conditional jump. */ - if (GET_CODE (PREV_INSN (loop_end)) != JUMP_INSN - || ! condjump_p (PREV_INSN (loop_end)) - || simplejump_p (PREV_INSN (loop_end))) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT instrumentation failed: invalid jump at loop end\n", - loop_num); - return; - } - - /* Make sure that the loop does not contain a function call - (the count register might be altered by the called function). */ - if (loop_has_call) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT instrumentation failed: function call in loop\n", - loop_num); - return; - } - - /* Make sure that the loop does not jump via a table. - (the count register might be used to perform the branch on table). */ - if (loop_has_tablejump) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT instrumentation failed: computed branch in the loop\n", - loop_num); - return; - } - - /* Account for loop unrolling in instrumented iteration count. */ - if (loop_info->unroll_number > 1) - n_iterations = loop_info->n_iterations / loop_info->unroll_number; - else - n_iterations = loop_info->n_iterations; - - if (n_iterations != 0 && n_iterations < 3) - { - /* Allow an enclosing outer loop to benefit if possible. */ - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: Too few iterations to benefit from BCT optimization\n", - loop_num); - return; - } - - /* Try to instrument the loop. */ - - /* Handle the simpler case, where the bounds are known at compile time. */ - if (n_iterations > 0) - { - /* Mark all enclosing loops that they cannot use count register. */ - for (i = loop_num; i != -1; i = loop_outer_loop[i]) - loop_used_count_register[i] = 1; - instrument_loop_bct (loop_start, loop_end, GEN_INT (n_iterations)); - return; - } - - /* Handle the more complex case, that the bounds are NOT known - at compile time. In this case we generate run_time calculation - of the number of iterations. */ - - if (loop_info->iteration_var == 0) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT Runtime Instrumentation failed: no loop iteration variable found\n", - loop_num); - return; - } - - if (GET_MODE_CLASS (GET_MODE (loop_info->iteration_var)) != MODE_INT - || GET_MODE_SIZE (GET_MODE (loop_info->iteration_var)) != UNITS_PER_WORD) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT Runtime Instrumentation failed: loop variable not integer\n", - loop_num); - return; - } - - /* With runtime bounds, if the compare is of the form '!=' we give up */ - if (loop_info->comparison_code == NE) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct %d: BCT Runtime Instrumentation failed: runtime bounds with != comparison\n", - loop_num); - return; - } -/* Use common loop preconditioning code instead. */ -#if 0 - else - { - /* We rely on the existence of run-time guard to ensure that the - loop executes at least once. */ - rtx sequence; - rtx iterations_num_reg; - - unsigned HOST_WIDE_INT increment_value_abs - = INTVAL (increment) * increment_direction; - - /* make sure that the increment is a power of two, otherwise (an - expensive) divide is needed. */ - if (exact_log2 (increment_value_abs) == -1) - { - if (loop_dump_stream) - fprintf (loop_dump_stream, - "insert_bct: not instrumenting BCT because the increment is not power of 2\n"); - return; - } + rtx cond; + int reverse; + rtx set; - /* compute the number of iterations */ - start_sequence (); - { - rtx temp_reg; - - /* Again, the number of iterations is calculated by: - ; - ; compare-val - initial-val + (increment -1) + additional-iteration - ; num_iterations = ----------------------------------------------------------------- - ; increment - */ - /* ??? Do we have to call copy_rtx here before passing rtx to - expand_binop? */ - if (compare_direction > 0) - { - /* <, <= :the loop variable is increasing */ - temp_reg = expand_binop (loop_var_mode, sub_optab, - comparison_value, initial_value, - NULL_RTX, 0, OPTAB_LIB_WIDEN); - } - else - { - temp_reg = expand_binop (loop_var_mode, sub_optab, - initial_value, comparison_value, - NULL_RTX, 0, OPTAB_LIB_WIDEN); - } + /* If this is not a standard conditional jump, we can't parse it. */ + if (GET_CODE (jump) != JUMP_INSN + || ! any_condjump_p (jump)) + return 0; + set = pc_set (jump); - if (increment_value_abs - 1 + add_iteration != 0) - temp_reg = expand_binop (loop_var_mode, add_optab, temp_reg, - GEN_INT (increment_value_abs - 1 - + add_iteration), - NULL_RTX, 0, OPTAB_LIB_WIDEN); + cond = XEXP (SET_SRC (set), 0); - if (increment_value_abs != 1) - { - /* ??? This will generate an expensive divide instruction for - most targets. The original authors apparently expected this - to be a shift, since they test for power-of-2 divisors above, - but just naively generating a divide instruction will not give - a shift. It happens to work for the PowerPC target because - the rs6000.md file has a divide pattern that emits shifts. - It will probably not work for any other target. */ - iterations_num_reg = expand_binop (loop_var_mode, sdiv_optab, - temp_reg, - GEN_INT (increment_value_abs), - NULL_RTX, 0, OPTAB_LIB_WIDEN); - } - else - iterations_num_reg = temp_reg; - } - sequence = gen_sequence (); - end_sequence (); - emit_insn_before (sequence, loop_start); - instrument_loop_bct (loop_start, loop_end, iterations_num_reg); - } + /* If this branches to JUMP_LABEL when the condition is false, reverse + the condition. */ + reverse + = GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF + && XEXP (XEXP (SET_SRC (set), 2), 0) == JUMP_LABEL (jump); - return; -#endif /* Complex case */ + return canonicalize_condition (jump, cond, reverse, earliest, NULL_RTX); } -/* Instrument loop by inserting a bct in it as follows: - 1. A new counter register is created. - 2. In the head of the loop the new variable is initialized to the value - passed in the loop_num_iterations parameter. - 3. At the end of the loop, comparison of the register with 0 is generated. - The created comparison follows the pattern defined for the - decrement_and_branch_on_count insn, so this insn will be generated. - 4. The branch on the old variable are deleted. The compare must remain - because it might be used elsewhere. If the loop-variable or condition - register are used elsewhere, they will be eliminated by flow. */ +/* Similar to above routine, except that we also put an invariant last + unless both operands are invariants. */ -static void -instrument_loop_bct (loop_start, loop_end, loop_num_iterations) - rtx loop_start, loop_end; - rtx loop_num_iterations; +rtx +get_condition_for_loop (loop, x) + const struct loop *loop; + rtx x; { - rtx counter_reg; - rtx start_label; - rtx sequence; + rtx comparison = get_condition (x, (rtx*) 0); - if (HAVE_decrement_and_branch_on_count) - { - if (loop_dump_stream) - { - fputs ("instrument_bct: Inserting BCT (", loop_dump_stream); - if (GET_CODE (loop_num_iterations) == CONST_INT) - fprintf (loop_dump_stream, HOST_WIDE_INT_PRINT_DEC, - INTVAL (loop_num_iterations)); - else - fputs ("runtime", loop_dump_stream); - fputs (" iterations)", loop_dump_stream); - } - - /* Discard original jump to continue loop. Original compare result - may still be live, so it cannot be discarded explicitly. */ - delete_insn (PREV_INSN (loop_end)); - - /* Insert the label which will delimit the start of the loop. */ - start_label = gen_label_rtx (); - emit_label_after (start_label, loop_start); - - /* Insert initialization of the count register into the loop header. */ - start_sequence (); - counter_reg = gen_reg_rtx (word_mode); - emit_insn (gen_move_insn (counter_reg, loop_num_iterations)); - sequence = gen_sequence (); - end_sequence (); - emit_insn_before (sequence, loop_start); - - /* Insert new comparison on the count register instead of the - old one, generating the needed BCT pattern (that will be - later recognized by assembly generation phase). */ - emit_jump_insn_before (gen_decrement_and_branch_on_count (counter_reg, - start_label), - loop_end); - JUMP_LABEL (prev_nonnote_insn (loop_end)) = start_label; - LABEL_NUSES (start_label)++; - } + if (comparison == 0 + || ! loop_invariant_p (loop, XEXP (comparison, 0)) + || loop_invariant_p (loop, XEXP (comparison, 1))) + return comparison; + return gen_rtx_fmt_ee (swap_condition (GET_CODE (comparison)), VOIDmode, + XEXP (comparison, 1), XEXP (comparison, 0)); } -#endif /* HAVE_decrement_and_branch_on_count */ /* Scan the function and determine whether it has indirect (computed) jumps. @@ -9421,6 +9341,7 @@ insert_loop_mem (mem, data) rtx *mem; void *data ATTRIBUTE_UNUSED; { + struct loop_info *loop_info = data; int i; rtx m = *mem; @@ -9432,312 +9353,521 @@ insert_loop_mem (mem, data) case MEM: break; + case CLOBBER: + /* We're not interested in MEMs that are only clobbered. */ + return -1; + case CONST_DOUBLE: /* We're not interested in the MEM associated with a CONST_DOUBLE, so there's no need to traverse into this. */ return -1; + case EXPR_LIST: + /* We're not interested in any MEMs that only appear in notes. */ + return -1; + default: /* This is not a MEM. */ return 0; } /* See if we've already seen this MEM. */ - for (i = 0; i < loop_mems_idx; ++i) - if (rtx_equal_p (m, loop_mems[i].mem)) + for (i = 0; i < loop_info->mems_idx; ++i) + if (rtx_equal_p (m, loop_info->mems[i].mem)) { - if (GET_MODE (m) != GET_MODE (loop_mems[i].mem)) + if (GET_MODE (m) != GET_MODE (loop_info->mems[i].mem)) /* The modes of the two memory accesses are different. If this happens, something tricky is going on, and we just don't optimize accesses to this MEM. */ - loop_mems[i].optimize = 0; + loop_info->mems[i].optimize = 0; return 0; } /* Resize the array, if necessary. */ - if (loop_mems_idx == loop_mems_allocated) + if (loop_info->mems_idx == loop_info->mems_allocated) { - if (loop_mems_allocated != 0) - loop_mems_allocated *= 2; + if (loop_info->mems_allocated != 0) + loop_info->mems_allocated *= 2; else - loop_mems_allocated = 32; + loop_info->mems_allocated = 32; - loop_mems = (loop_mem_info*) - xrealloc (loop_mems, - loop_mems_allocated * sizeof (loop_mem_info)); + loop_info->mems = (loop_mem_info *) + xrealloc (loop_info->mems, + loop_info->mems_allocated * sizeof (loop_mem_info)); } /* Actually insert the MEM. */ - loop_mems[loop_mems_idx].mem = m; + loop_info->mems[loop_info->mems_idx].mem = m; /* We can't hoist this MEM out of the loop if it's a BLKmode MEM because we can't put it in a register. We still store it in the table, though, so that if we see the same address later, but in a non-BLK mode, we'll not think we can optimize it at that point. */ - loop_mems[loop_mems_idx].optimize = (GET_MODE (m) != BLKmode); - loop_mems[loop_mems_idx].reg = NULL_RTX; - ++loop_mems_idx; + loop_info->mems[loop_info->mems_idx].optimize = (GET_MODE (m) != BLKmode); + loop_info->mems[loop_info->mems_idx].reg = NULL_RTX; + ++loop_info->mems_idx; return 0; } -/* Like load_mems, but also ensures that SET_IN_LOOP, - MAY_NOT_OPTIMIZE, REG_SINGLE_USAGE, and INSN_COUNT have the correct - values after load_mems. */ + +/* Allocate REGS->ARRAY or reallocate it if it is too small. + + Increment REGS->ARRAY[I].SET_IN_LOOP at the index I of each + register that is modified by an insn between FROM and TO. If the + value of an element of REGS->array[I].SET_IN_LOOP becomes 127 or + more, stop incrementing it, to avoid overflow. + + Store in REGS->ARRAY[I].SINGLE_USAGE the single insn in which + register I is used, if it is only used once. Otherwise, it is set + to 0 (for no uses) or const0_rtx for more than one use. This + parameter may be zero, in which case this processing is not done. + + Set REGS->ARRAY[I].MAY_NOT_OPTIMIZE nonzero if we should not + optimize register I. */ static void -load_mems_and_recount_loop_regs_set (scan_start, end, loop_top, start, - insn_count) - rtx scan_start; - rtx end; - rtx loop_top; - rtx start; - int *insn_count; +loop_regs_scan (loop, extra_size) + const struct loop *loop; + int extra_size; { - int nregs = max_reg_num (); + struct loop_regs *regs = LOOP_REGS (loop); + int old_nregs; + /* last_set[n] is nonzero iff reg n has been set in the current + basic block. In that case, it is the insn that last set reg n. */ + rtx *last_set; + rtx insn; + int i; + + old_nregs = regs->num; + regs->num = max_reg_num (); - load_mems (scan_start, end, loop_top, start); - - /* Recalculate set_in_loop and friends since load_mems may have - created new registers. */ - if (max_reg_num () > nregs) + /* Grow the regs array if not allocated or too small. */ + if (regs->num >= regs->size) { - int i; - int old_nregs; + regs->size = regs->num + extra_size; - old_nregs = nregs; - nregs = max_reg_num (); + regs->array = (struct loop_reg *) + xrealloc (regs->array, regs->size * sizeof (*regs->array)); - if ((unsigned) nregs > set_in_loop->num_elements) - { - /* Grow all the arrays. */ - VARRAY_GROW (set_in_loop, nregs); - VARRAY_GROW (n_times_set, nregs); - VARRAY_GROW (may_not_optimize, nregs); - VARRAY_GROW (reg_single_usage, nregs); - } - /* Clear the arrays */ - bzero ((char *) &set_in_loop->data, nregs * sizeof (int)); - bzero ((char *) &may_not_optimize->data, nregs * sizeof (char)); - bzero ((char *) ®_single_usage->data, nregs * sizeof (rtx)); + /* Zero the new elements. */ + memset (regs->array + old_nregs, 0, + (regs->size - old_nregs) * sizeof (*regs->array)); + } + + /* Clear previously scanned fields but do not clear n_times_set. */ + for (i = 0; i < old_nregs; i++) + { + regs->array[i].set_in_loop = 0; + regs->array[i].may_not_optimize = 0; + regs->array[i].single_usage = NULL_RTX; + } - count_loop_regs_set (loop_top ? loop_top : start, end, - may_not_optimize, reg_single_usage, - insn_count, nregs); + last_set = (rtx *) xcalloc (regs->num, sizeof (rtx)); - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) + /* Scan the loop, recording register usage. */ + for (insn = loop->top ? loop->top : loop->start; insn != loop->end; + insn = NEXT_INSN (insn)) + { + if (INSN_P (insn)) { - VARRAY_CHAR (may_not_optimize, i) = 1; - VARRAY_INT (set_in_loop, i) = 1; + /* Record registers that have exactly one use. */ + find_single_use_in_loop (regs, insn, PATTERN (insn)); + + /* Include uses in REG_EQUAL notes. */ + if (REG_NOTES (insn)) + find_single_use_in_loop (regs, insn, REG_NOTES (insn)); + + if (GET_CODE (PATTERN (insn)) == SET + || GET_CODE (PATTERN (insn)) == CLOBBER) + count_one_set (regs, insn, PATTERN (insn), last_set); + else if (GET_CODE (PATTERN (insn)) == PARALLEL) + { + int i; + for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) + count_one_set (regs, insn, XVECEXP (PATTERN (insn), 0, i), + last_set); + } } - + + if (GET_CODE (insn) == CODE_LABEL || GET_CODE (insn) == JUMP_INSN) + memset (last_set, 0, regs->num * sizeof (rtx)); + } + + /* Invalidate all hard registers clobbered by calls. With one exception: + a call-clobbered PIC register is still function-invariant for our + purposes, since we can hoist any PIC calculations out of the loop. + Thus the call to rtx_varies_p. */ + if (LOOP_INFO (loop)->has_call) + for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) + if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i) + && rtx_varies_p (gen_rtx_REG (Pmode, i), /*for_alias=*/1)) + { + regs->array[i].may_not_optimize = 1; + regs->array[i].set_in_loop = 1; + } + #ifdef AVOID_CCMODE_COPIES - /* Don't try to move insns which set CC registers if we should not - create CCmode register copies. */ - for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) - if (GET_MODE_CLASS (GET_MODE (regno_reg_rtx[i])) == MODE_CC) - VARRAY_CHAR (may_not_optimize, i) = 1; + /* Don't try to move insns which set CC registers if we should not + create CCmode register copies. */ + for (i = regs->num - 1; i >= FIRST_PSEUDO_REGISTER; i--) + if (GET_MODE_CLASS (GET_MODE (regno_reg_rtx[i])) == MODE_CC) + regs->array[i].may_not_optimize = 1; #endif - /* Set n_times_set for the new registers. */ - bcopy ((char *) (&set_in_loop->data.i[0] + old_nregs), - (char *) (&n_times_set->data.i[0] + old_nregs), - (nregs - old_nregs) * sizeof (int)); - } + /* Set regs->array[I].n_times_set for the new registers. */ + for (i = old_nregs; i < regs->num; i++) + regs->array[i].n_times_set = regs->array[i].set_in_loop; + + free (last_set); } -/* Move MEMs into registers for the duration of the loop. SCAN_START - is the first instruction in the loop (as it is executed). The - other parameters are as for next_insn_in_loop. */ +/* Returns the number of real INSNs in the LOOP. */ + +static int +count_insns_in_loop (loop) + const struct loop *loop; +{ + int count = 0; + rtx insn; + + for (insn = loop->top ? loop->top : loop->start; insn != loop->end; + insn = NEXT_INSN (insn)) + if (INSN_P (insn)) + ++count; + + return count; +} + +/* Move MEMs into registers for the duration of the loop. */ static void -load_mems (scan_start, end, loop_top, start) - rtx scan_start; - rtx end; - rtx loop_top; - rtx start; +load_mems (loop) + const struct loop *loop; { + struct loop_info *loop_info = LOOP_INFO (loop); + struct loop_regs *regs = LOOP_REGS (loop); int maybe_never = 0; int i; - rtx p; + rtx p, prev_ebb_head; rtx label = NULL_RTX; rtx end_label; + /* Nonzero if the next instruction may never be executed. */ + int next_maybe_never = 0; + unsigned int last_max_reg = max_reg_num (); - if (loop_mems_idx > 0) - { - /* Nonzero if the next instruction may never be executed. */ - int next_maybe_never = 0; + if (loop_info->mems_idx == 0) + return; + + /* We cannot use next_label here because it skips over normal insns. */ + end_label = next_nonnote_insn (loop->end); + if (end_label && GET_CODE (end_label) != CODE_LABEL) + end_label = NULL_RTX; - /* Check to see if it's possible that some instructions in the - loop are never executed. */ - for (p = next_insn_in_loop (scan_start, scan_start, end, loop_top); - p != NULL_RTX && !maybe_never; - p = next_insn_in_loop (p, scan_start, end, loop_top)) + /* Check to see if it's possible that some instructions in the loop are + never executed. Also check if there is a goto out of the loop other + than right after the end of the loop. */ + for (p = next_insn_in_loop (loop, loop->scan_start); + p != NULL_RTX; + p = next_insn_in_loop (loop, p)) + { + if (GET_CODE (p) == CODE_LABEL) + maybe_never = 1; + else if (GET_CODE (p) == JUMP_INSN + /* If we enter the loop in the middle, and scan + around to the beginning, don't set maybe_never + for that. This must be an unconditional jump, + otherwise the code at the top of the loop might + never be executed. Unconditional jumps are + followed a by barrier then loop end. */ + && ! (GET_CODE (p) == JUMP_INSN + && JUMP_LABEL (p) == loop->top + && NEXT_INSN (NEXT_INSN (p)) == loop->end + && any_uncondjump_p (p))) { - if (GET_CODE (p) == CODE_LABEL) + /* If this is a jump outside of the loop but not right + after the end of the loop, we would have to emit new fixup + sequences for each such label. */ + if (/* If we can't tell where control might go when this + JUMP_INSN is executed, we must be conservative. */ + !JUMP_LABEL (p) + || (JUMP_LABEL (p) != end_label + && (INSN_UID (JUMP_LABEL (p)) >= max_uid_for_loop + || INSN_LUID (JUMP_LABEL (p)) < INSN_LUID (loop->start) + || INSN_LUID (JUMP_LABEL (p)) > INSN_LUID (loop->end)))) + return; + + if (!any_condjump_p (p)) + /* Something complicated. */ maybe_never = 1; - else if (GET_CODE (p) == JUMP_INSN - /* If we enter the loop in the middle, and scan - around to the beginning, don't set maybe_never - for that. This must be an unconditional jump, - otherwise the code at the top of the loop might - never be executed. Unconditional jumps are - followed a by barrier then loop end. */ - && ! (GET_CODE (p) == JUMP_INSN - && JUMP_LABEL (p) == loop_top - && NEXT_INSN (NEXT_INSN (p)) == end - && simplejump_p (p))) + else + /* If there are any more instructions in the loop, they + might not be reached. */ + next_maybe_never = 1; + } + else if (next_maybe_never) + maybe_never = 1; + } + + /* Find start of the extended basic block that enters the loop. */ + for (p = loop->start; + PREV_INSN (p) && GET_CODE (p) != CODE_LABEL; + p = PREV_INSN (p)) + ; + prev_ebb_head = p; + + cselib_init (); + + /* Build table of mems that get set to constant values before the + loop. */ + for (; p != loop->start; p = NEXT_INSN (p)) + cselib_process_insn (p); + + /* Actually move the MEMs. */ + for (i = 0; i < loop_info->mems_idx; ++i) + { + regset_head load_copies; + regset_head store_copies; + int written = 0; + rtx reg; + rtx mem = loop_info->mems[i].mem; + rtx mem_list_entry; + + if (MEM_VOLATILE_P (mem) + || loop_invariant_p (loop, XEXP (mem, 0)) != 1) + /* There's no telling whether or not MEM is modified. */ + loop_info->mems[i].optimize = 0; + + /* Go through the MEMs written to in the loop to see if this + one is aliased by one of them. */ + mem_list_entry = loop_info->store_mems; + while (mem_list_entry) + { + if (rtx_equal_p (mem, XEXP (mem_list_entry, 0))) + written = 1; + else if (true_dependence (XEXP (mem_list_entry, 0), VOIDmode, + mem, rtx_varies_p)) { - if (!condjump_p (p)) - /* Something complicated. */ - maybe_never = 1; - else - /* If there are any more instructions in the loop, they - might not be reached. */ - next_maybe_never = 1; - } - else if (next_maybe_never) - maybe_never = 1; + /* MEM is indeed aliased by this store. */ + loop_info->mems[i].optimize = 0; + break; + } + mem_list_entry = XEXP (mem_list_entry, 1); } - /* Actually move the MEMs. */ - for (i = 0; i < loop_mems_idx; ++i) + if (flag_float_store && written + && GET_MODE_CLASS (GET_MODE (mem)) == MODE_FLOAT) + loop_info->mems[i].optimize = 0; + + /* If this MEM is written to, we must be sure that there + are no reads from another MEM that aliases this one. */ + if (loop_info->mems[i].optimize && written) { - int written = 0; - rtx reg; - rtx mem = loop_mems[i].mem; - rtx mem_list_entry; - - if (MEM_VOLATILE_P (mem) - || invariant_p (XEXP (mem, 0)) != 1) - /* There's no telling whether or not MEM is modified. */ - loop_mems[i].optimize = 0; - - /* Go through the MEMs written to in the loop to see if this - one is aliased by one of them. */ - mem_list_entry = loop_store_mems; - while (mem_list_entry) + int j; + + for (j = 0; j < loop_info->mems_idx; ++j) { - if (rtx_equal_p (mem, XEXP (mem_list_entry, 0))) - written = 1; - else if (true_dependence (XEXP (mem_list_entry, 0), VOIDmode, - mem, rtx_varies_p)) + if (j == i) + continue; + else if (true_dependence (mem, + VOIDmode, + loop_info->mems[j].mem, + rtx_varies_p)) { - /* MEM is indeed aliased by this store. */ - loop_mems[i].optimize = 0; + /* It's not safe to hoist loop_info->mems[i] out of + the loop because writes to it might not be + seen by reads from loop_info->mems[j]. */ + loop_info->mems[i].optimize = 0; break; } - mem_list_entry = XEXP (mem_list_entry, 1); } - - if (flag_float_store && written - && GET_MODE_CLASS (GET_MODE (mem)) == MODE_FLOAT) - loop_mems[i].optimize = 0; - - /* If this MEM is written to, we must be sure that there - are no reads from another MEM that aliases this one. */ - if (loop_mems[i].optimize && written) + } + + if (maybe_never && may_trap_p (mem)) + /* We can't access the MEM outside the loop; it might + cause a trap that wouldn't have happened otherwise. */ + loop_info->mems[i].optimize = 0; + + if (!loop_info->mems[i].optimize) + /* We thought we were going to lift this MEM out of the + loop, but later discovered that we could not. */ + continue; + + INIT_REG_SET (&load_copies); + INIT_REG_SET (&store_copies); + + /* Allocate a pseudo for this MEM. We set REG_USERVAR_P in + order to keep scan_loop from moving stores to this MEM + out of the loop just because this REG is neither a + user-variable nor used in the loop test. */ + reg = gen_reg_rtx (GET_MODE (mem)); + REG_USERVAR_P (reg) = 1; + loop_info->mems[i].reg = reg; + + /* Now, replace all references to the MEM with the + corresponding pseudos. */ + maybe_never = 0; + for (p = next_insn_in_loop (loop, loop->scan_start); + p != NULL_RTX; + p = next_insn_in_loop (loop, p)) + { + if (INSN_P (p)) { - int j; + rtx set; - for (j = 0; j < loop_mems_idx; ++j) - { - if (j == i) - continue; - else if (true_dependence (mem, - VOIDmode, - loop_mems[j].mem, - rtx_varies_p)) - { - /* It's not safe to hoist loop_mems[i] out of - the loop because writes to it might not be - seen by reads from loop_mems[j]. */ - loop_mems[i].optimize = 0; - break; - } - } + set = single_set (p); + + /* See if this copies the mem into a register that isn't + modified afterwards. We'll try to do copy propagation + a little further on. */ + if (set + /* @@@ This test is _way_ too conservative. */ + && ! maybe_never + && GET_CODE (SET_DEST (set)) == REG + && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER + && REGNO (SET_DEST (set)) < last_max_reg + && regs->array[REGNO (SET_DEST (set))].n_times_set == 1 + && rtx_equal_p (SET_SRC (set), mem)) + SET_REGNO_REG_SET (&load_copies, REGNO (SET_DEST (set))); + + /* See if this copies the mem from a register that isn't + modified afterwards. We'll try to remove the + redundant copy later on by doing a little register + renaming and copy propagation. This will help + to untangle things for the BIV detection code. */ + if (set + && ! maybe_never + && GET_CODE (SET_SRC (set)) == REG + && REGNO (SET_SRC (set)) >= FIRST_PSEUDO_REGISTER + && REGNO (SET_SRC (set)) < last_max_reg + && regs->array[REGNO (SET_SRC (set))].n_times_set == 1 + && rtx_equal_p (SET_DEST (set), mem)) + SET_REGNO_REG_SET (&store_copies, REGNO (SET_SRC (set))); + + /* Replace the memory reference with the shadow register. */ + replace_loop_mems (p, loop_info->mems[i].mem, + loop_info->mems[i].reg); } - if (maybe_never && may_trap_p (mem)) - /* We can't access the MEM outside the loop; it might - cause a trap that wouldn't have happened otherwise. */ - loop_mems[i].optimize = 0; - - if (!loop_mems[i].optimize) - /* We thought we were going to lift this MEM out of the - loop, but later discovered that we could not. */ - continue; + if (GET_CODE (p) == CODE_LABEL + || GET_CODE (p) == JUMP_INSN) + maybe_never = 1; + } - /* Allocate a pseudo for this MEM. We set REG_USERVAR_P in - order to keep scan_loop from moving stores to this MEM - out of the loop just because this REG is neither a - user-variable nor used in the loop test. */ - reg = gen_reg_rtx (GET_MODE (mem)); - REG_USERVAR_P (reg) = 1; - loop_mems[i].reg = reg; - - /* Now, replace all references to the MEM with the - corresponding pesudos. */ - for (p = next_insn_in_loop (scan_start, scan_start, end, loop_top); - p != NULL_RTX; - p = next_insn_in_loop (p, scan_start, end, loop_top)) + if (! apply_change_group ()) + /* We couldn't replace all occurrences of the MEM. */ + loop_info->mems[i].optimize = 0; + else + { + /* Load the memory immediately before LOOP->START, which is + the NOTE_LOOP_BEG. */ + cselib_val *e = cselib_lookup (mem, VOIDmode, 0); + rtx set; + rtx best = mem; + int j; + struct elt_loc_list *const_equiv = 0; + + if (e) { - rtx_and_int ri; - ri.r = p; - ri.i = i; - for_each_rtx (&p, replace_loop_mem, &ri); + struct elt_loc_list *equiv; + struct elt_loc_list *best_equiv = 0; + for (equiv = e->locs; equiv; equiv = equiv->next) + { + if (CONSTANT_P (equiv->loc)) + const_equiv = equiv; + else if (GET_CODE (equiv->loc) == REG + /* Extending hard register lifetimes causes crash + on SRC targets. Doing so on non-SRC is + probably also not good idea, since we most + probably have pseudoregister equivalence as + well. */ + && REGNO (equiv->loc) >= FIRST_PSEUDO_REGISTER) + best_equiv = equiv; + } + /* Use the constant equivalence if that is cheap enough. */ + if (! best_equiv) + best_equiv = const_equiv; + else if (const_equiv + && (rtx_cost (const_equiv->loc, SET) + <= rtx_cost (best_equiv->loc, SET))) + { + best_equiv = const_equiv; + const_equiv = 0; + } + + /* If best_equiv is nonzero, we know that MEM is set to a + constant or register before the loop. We will use this + knowledge to initialize the shadow register with that + constant or reg rather than by loading from MEM. */ + if (best_equiv) + best = copy_rtx (best_equiv->loc); } - if (!apply_change_group ()) - /* We couldn't replace all occurrences of the MEM. */ - loop_mems[i].optimize = 0; - else + set = gen_move_insn (reg, best); + set = loop_insn_hoist (loop, set); + if (REG_P (best)) { - rtx set; + for (p = prev_ebb_head; p != loop->start; p = NEXT_INSN (p)) + if (REGNO_LAST_UID (REGNO (best)) == INSN_UID (p)) + { + REGNO_LAST_UID (REGNO (best)) = INSN_UID (set); + break; + } + } - /* Load the memory immediately before START, which is - the NOTE_LOOP_BEG. */ - set = gen_move_insn (reg, mem); - emit_insn_before (set, start); + if (const_equiv) + set_unique_reg_note (set, REG_EQUAL, copy_rtx (const_equiv->loc)); - if (written) + if (written) + { + if (label == NULL_RTX) { - if (label == NULL_RTX) - { - /* We must compute the former - right-after-the-end label before we insert - the new one. */ - end_label = next_label (end); - label = gen_label_rtx (); - emit_label_after (label, end); - } - - /* Store the memory immediately after END, which is - the NOTE_LOOP_END. */ - set = gen_move_insn (copy_rtx (mem), reg); - emit_insn_after (set, label); + label = gen_label_rtx (); + emit_label_after (label, loop->end); } - if (loop_dump_stream) - { - fprintf (loop_dump_stream, "Hoisted regno %d %s from ", - REGNO (reg), (written ? "r/w" : "r/o")); - print_rtl (loop_dump_stream, mem); - fputc ('\n', loop_dump_stream); - } + /* Store the memory immediately after END, which is + the NOTE_LOOP_END. */ + set = gen_move_insn (copy_rtx (mem), reg); + loop_insn_emit_after (loop, 0, label, set); + } + + if (loop_dump_stream) + { + fprintf (loop_dump_stream, "Hoisted regno %d %s from ", + REGNO (reg), (written ? "r/w" : "r/o")); + print_rtl (loop_dump_stream, mem); + fputc ('\n', loop_dump_stream); } + + /* Attempt a bit of copy propagation. This helps untangle the + data flow, and enables {basic,general}_induction_var to find + more bivs/givs. */ + EXECUTE_IF_SET_IN_REG_SET + (&load_copies, FIRST_PSEUDO_REGISTER, j, + { + try_copy_prop (loop, reg, j); + }); + CLEAR_REG_SET (&load_copies); + + EXECUTE_IF_SET_IN_REG_SET + (&store_copies, FIRST_PSEUDO_REGISTER, j, + { + try_swap_copy_prop (loop, reg, j); + }); + CLEAR_REG_SET (&store_copies); } } - if (label != NULL_RTX) + if (label != NULL_RTX && end_label != NULL_RTX) { /* Now, we need to replace all references to the previous exit label with the new one. */ - rtx_pair rr; + rtx_pair rr; rr.r1 = end_label; rr.r2 = label; - for (p = start; p != end; p = NEXT_INSN (p)) + for (p = loop->start; p != loop->end; p = NEXT_INSN (p)) { for_each_rtx (&p, replace_label, &rr); @@ -9751,11 +9881,245 @@ load_mems (scan_start, end, loop_top, start) JUMP_LABEL (p) = label; } } + + cselib_finish (); +} + +/* For communication between note_reg_stored and its caller. */ +struct note_reg_stored_arg +{ + int set_seen; + rtx reg; +}; + +/* Called via note_stores, record in SET_SEEN whether X, which is written, + is equal to ARG. */ +static void +note_reg_stored (x, setter, arg) + rtx x, setter ATTRIBUTE_UNUSED; + void *arg; +{ + struct note_reg_stored_arg *t = (struct note_reg_stored_arg *) arg; + if (t->reg == x) + t->set_seen = 1; +} + +/* Try to replace every occurrence of pseudo REGNO with REPLACEMENT. + There must be exactly one insn that sets this pseudo; it will be + deleted if all replacements succeed and we can prove that the register + is not used after the loop. */ + +static void +try_copy_prop (loop, replacement, regno) + const struct loop *loop; + rtx replacement; + unsigned int regno; +{ + /* This is the reg that we are copying from. */ + rtx reg_rtx = regno_reg_rtx[regno]; + rtx init_insn = 0; + rtx insn; + /* These help keep track of whether we replaced all uses of the reg. */ + int replaced_last = 0; + int store_is_first = 0; + + for (insn = next_insn_in_loop (loop, loop->scan_start); + insn != NULL_RTX; + insn = next_insn_in_loop (loop, insn)) + { + rtx set; + + /* Only substitute within one extended basic block from the initializing + insn. */ + if (GET_CODE (insn) == CODE_LABEL && init_insn) + break; + + if (! INSN_P (insn)) + continue; + + /* Is this the initializing insn? */ + set = single_set (insn); + if (set + && GET_CODE (SET_DEST (set)) == REG + && REGNO (SET_DEST (set)) == regno) + { + if (init_insn) + abort (); + + init_insn = insn; + if (REGNO_FIRST_UID (regno) == INSN_UID (insn)) + store_is_first = 1; + } + + /* Only substitute after seeing the initializing insn. */ + if (init_insn && insn != init_insn) + { + struct note_reg_stored_arg arg; + + replace_loop_regs (insn, reg_rtx, replacement); + if (REGNO_LAST_UID (regno) == INSN_UID (insn)) + replaced_last = 1; + + /* Stop replacing when REPLACEMENT is modified. */ + arg.reg = replacement; + arg.set_seen = 0; + note_stores (PATTERN (insn), note_reg_stored, &arg); + if (arg.set_seen) + { + rtx note = find_reg_note (insn, REG_EQUAL, NULL); + + /* It is possible that we've turned previously valid REG_EQUAL to + invalid, as we change the REGNO to REPLACEMENT and unlike REGNO, + REPLACEMENT is modified, we get different meaning. */ + if (note && reg_mentioned_p (replacement, XEXP (note, 0))) + remove_note (insn, note); + break; + } + } + } + if (! init_insn) + abort (); + if (apply_change_group ()) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, " Replaced reg %d", regno); + if (store_is_first && replaced_last) + { + rtx first; + rtx retval_note; + + /* Assume we're just deleting INIT_INSN. */ + first = init_insn; + /* Look for REG_RETVAL note. If we're deleting the end of + the libcall sequence, the whole sequence can go. */ + retval_note = find_reg_note (init_insn, REG_RETVAL, NULL_RTX); + /* If we found a REG_RETVAL note, find the first instruction + in the sequence. */ + if (retval_note) + first = XEXP (retval_note, 0); + + /* Delete the instructions. */ + loop_delete_insns (first, init_insn); + } + if (loop_dump_stream) + fprintf (loop_dump_stream, ".\n"); + } +} + +/* Replace all the instructions from FIRST up to and including LAST + with NOTE_INSN_DELETED notes. */ + +static void +loop_delete_insns (first, last) + rtx first; + rtx last; +{ + while (1) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, ", deleting init_insn (%d)", + INSN_UID (first)); + delete_insn (first); + + /* If this was the LAST instructions we're supposed to delete, + we're done. */ + if (first == last) + break; + + first = NEXT_INSN (first); + } +} + +/* Try to replace occurrences of pseudo REGNO with REPLACEMENT within + loop LOOP if the order of the sets of these registers can be + swapped. There must be exactly one insn within the loop that sets + this pseudo followed immediately by a move insn that sets + REPLACEMENT with REGNO. */ +static void +try_swap_copy_prop (loop, replacement, regno) + const struct loop *loop; + rtx replacement; + unsigned int regno; +{ + rtx insn; + rtx set = NULL_RTX; + unsigned int new_regno; + + new_regno = REGNO (replacement); + + for (insn = next_insn_in_loop (loop, loop->scan_start); + insn != NULL_RTX; + insn = next_insn_in_loop (loop, insn)) + { + /* Search for the insn that copies REGNO to NEW_REGNO? */ + if (INSN_P (insn) + && (set = single_set (insn)) + && GET_CODE (SET_DEST (set)) == REG + && REGNO (SET_DEST (set)) == new_regno + && GET_CODE (SET_SRC (set)) == REG + && REGNO (SET_SRC (set)) == regno) + break; + } + + if (insn != NULL_RTX) + { + rtx prev_insn; + rtx prev_set; + + /* Some DEF-USE info would come in handy here to make this + function more general. For now, just check the previous insn + which is the most likely candidate for setting REGNO. */ + + prev_insn = PREV_INSN (insn); + + if (INSN_P (insn) + && (prev_set = single_set (prev_insn)) + && GET_CODE (SET_DEST (prev_set)) == REG + && REGNO (SET_DEST (prev_set)) == regno) + { + /* We have: + (set (reg regno) (expr)) + (set (reg new_regno) (reg regno)) + + so try converting this to: + (set (reg new_regno) (expr)) + (set (reg regno) (reg new_regno)) + + The former construct is often generated when a global + variable used for an induction variable is shadowed by a + register (NEW_REGNO). The latter construct improves the + chances of GIV replacement and BIV elimination. */ + + validate_change (prev_insn, &SET_DEST (prev_set), + replacement, 1); + validate_change (insn, &SET_DEST (set), + SET_SRC (set), 1); + validate_change (insn, &SET_SRC (set), + replacement, 1); + + if (apply_change_group ()) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, + " Swapped set of reg %d at %d with reg %d at %d.\n", + regno, INSN_UID (insn), + new_regno, INSN_UID (prev_insn)); + + /* Update first use of REGNO. */ + if (REGNO_FIRST_UID (regno) == INSN_UID (prev_insn)) + REGNO_FIRST_UID (regno) = INSN_UID (insn); + + /* Now perform copy propagation to hopefully + remove all uses of REGNO within the loop. */ + try_copy_prop (loop, replacement, regno); + } + } + } } /* Replace MEM with its associated pseudo register. This function is - called from load_mems via for_each_rtx. DATA is actually an - rtx_and_int * describing the instruction currently being scanned + called from load_mems via for_each_rtx. DATA is actually a pointer + to a structure describing the instruction currently being scanned and the MEM we are currently replacing. */ static int @@ -9763,9 +10127,7 @@ replace_loop_mem (mem, data) rtx *mem; void *data; { - rtx_and_int *ri; - rtx insn; - int i; + loop_replace_args *args = (loop_replace_args *) data; rtx m = *mem; if (m == NULL_RTX) @@ -9786,21 +10148,67 @@ replace_loop_mem (mem, data) return 0; } - ri = (rtx_and_int*) data; - i = ri->i; - - if (!rtx_equal_p (loop_mems[i].mem, m)) + if (!rtx_equal_p (args->match, m)) /* This is not the MEM we are currently replacing. */ return 0; - insn = ri->r; - /* Actually replace the MEM. */ - validate_change (insn, mem, loop_mems[i].reg, 1); + validate_change (args->insn, mem, args->replacement, 1); + + return 0; +} + +static void +replace_loop_mems (insn, mem, reg) + rtx insn; + rtx mem; + rtx reg; +{ + loop_replace_args args; + + args.insn = insn; + args.match = mem; + args.replacement = reg; + + for_each_rtx (&insn, replace_loop_mem, &args); +} + +/* Replace one register with another. Called through for_each_rtx; PX points + to the rtx being scanned. DATA is actually a pointer to + a structure of arguments. */ + +static int +replace_loop_reg (px, data) + rtx *px; + void *data; +{ + rtx x = *px; + loop_replace_args *args = (loop_replace_args *) data; + + if (x == NULL_RTX) + return 0; + + if (x == args->match) + validate_change (args->insn, px, args->replacement, 1); return 0; } +static void +replace_loop_regs (insn, reg, replacement) + rtx insn; + rtx reg; + rtx replacement; +{ + loop_replace_args args; + + args.insn = insn; + args.match = reg; + args.replacement = replacement; + + for_each_rtx (&insn, replace_loop_reg, &args); +} + /* Replace occurrences of the old exit label for the loop with the new one. DATA is an rtx_pair containing the old and new labels, respectively. */ @@ -9811,8 +10219,8 @@ replace_label (x, data) void *data; { rtx l = *x; - rtx old_label = ((rtx_pair*) data)->r1; - rtx new_label = ((rtx_pair*) data)->r2; + rtx old_label = ((rtx_pair *) data)->r1; + rtx new_label = ((rtx_pair *) data)->r2; if (l == NULL_RTX) return 0; @@ -9822,11 +10230,411 @@ replace_label (x, data) if (XEXP (l, 0) != old_label) return 0; - + XEXP (l, 0) = new_label; ++LABEL_NUSES (new_label); --LABEL_NUSES (old_label); return 0; } + +/* Emit insn for PATTERN after WHERE_INSN in basic block WHERE_BB + (ignored in the interim). */ +static rtx +loop_insn_emit_after (loop, where_bb, where_insn, pattern) + const struct loop *loop ATTRIBUTE_UNUSED; + basic_block where_bb ATTRIBUTE_UNUSED; + rtx where_insn; + rtx pattern; +{ + return emit_insn_after (pattern, where_insn); +} + + +/* If WHERE_INSN is non-zero emit insn for PATTERN before WHERE_INSN + in basic block WHERE_BB (ignored in the interim) within the loop + otherwise hoist PATTERN into the loop pre-header. */ + +rtx +loop_insn_emit_before (loop, where_bb, where_insn, pattern) + const struct loop *loop; + basic_block where_bb ATTRIBUTE_UNUSED; + rtx where_insn; + rtx pattern; +{ + if (! where_insn) + return loop_insn_hoist (loop, pattern); + return emit_insn_before (pattern, where_insn); +} + + +/* Emit call insn for PATTERN before WHERE_INSN in basic block + WHERE_BB (ignored in the interim) within the loop. */ + +static rtx +loop_call_insn_emit_before (loop, where_bb, where_insn, pattern) + const struct loop *loop ATTRIBUTE_UNUSED; + basic_block where_bb ATTRIBUTE_UNUSED; + rtx where_insn; + rtx pattern; +{ + return emit_call_insn_before (pattern, where_insn); +} + + +/* Hoist insn for PATTERN into the loop pre-header. */ + +rtx +loop_insn_hoist (loop, pattern) + const struct loop *loop; + rtx pattern; +{ + return loop_insn_emit_before (loop, 0, loop->start, pattern); +} + + +/* Hoist call insn for PATTERN into the loop pre-header. */ + +static rtx +loop_call_insn_hoist (loop, pattern) + const struct loop *loop; + rtx pattern; +{ + return loop_call_insn_emit_before (loop, 0, loop->start, pattern); +} + + +/* Sink insn for PATTERN after the loop end. */ + +rtx +loop_insn_sink (loop, pattern) + const struct loop *loop; + rtx pattern; +{ + return loop_insn_emit_before (loop, 0, loop->sink, pattern); +} + + +/* If the loop has multiple exits, emit insn for PATTERN before the + loop to ensure that it will always be executed no matter how the + loop exits. Otherwise, emit the insn for PATTERN after the loop, + since this is slightly more efficient. */ + +static rtx +loop_insn_sink_or_swim (loop, pattern) + const struct loop *loop; + rtx pattern; +{ + if (loop->exit_count) + return loop_insn_hoist (loop, pattern); + else + return loop_insn_sink (loop, pattern); +} + +static void +loop_ivs_dump (loop, file, verbose) + const struct loop *loop; + FILE *file; + int verbose; +{ + struct iv_class *bl; + int iv_num = 0; + + if (! loop || ! file) + return; + + for (bl = LOOP_IVS (loop)->list; bl; bl = bl->next) + iv_num++; + + fprintf (file, "Loop %d: %d IV classes\n", loop->num, iv_num); + + for (bl = LOOP_IVS (loop)->list; bl; bl = bl->next) + { + loop_iv_class_dump (bl, file, verbose); + fputc ('\n', file); + } +} + + +static void +loop_iv_class_dump (bl, file, verbose) + const struct iv_class *bl; + FILE *file; + int verbose ATTRIBUTE_UNUSED; +{ + struct induction *v; + rtx incr; + int i; + + if (! bl || ! file) + return; + + fprintf (file, "IV class for reg %d, benefit %d\n", + bl->regno, bl->total_benefit); + + fprintf (file, " Init insn %d", INSN_UID (bl->init_insn)); + if (bl->initial_value) + { + fprintf (file, ", init val: "); + print_simple_rtl (file, bl->initial_value); + } + if (bl->initial_test) + { + fprintf (file, ", init test: "); + print_simple_rtl (file, bl->initial_test); + } + fputc ('\n', file); + + if (bl->final_value) + { + fprintf (file, " Final val: "); + print_simple_rtl (file, bl->final_value); + fputc ('\n', file); + } + + if ((incr = biv_total_increment (bl))) + { + fprintf (file, " Total increment: "); + print_simple_rtl (file, incr); + fputc ('\n', file); + } + + /* List the increments. */ + for (i = 0, v = bl->biv; v; v = v->next_iv, i++) + { + fprintf (file, " Inc%d: insn %d, incr: ", i, INSN_UID (v->insn)); + print_simple_rtl (file, v->add_val); + fputc ('\n', file); + } + + /* List the givs. */ + for (i = 0, v = bl->giv; v; v = v->next_iv, i++) + { + fprintf (file, " Giv%d: insn %d, benefit %d, ", + i, INSN_UID (v->insn), v->benefit); + if (v->giv_type == DEST_ADDR) + print_simple_rtl (file, v->mem); + else + print_simple_rtl (file, single_set (v->insn)); + fputc ('\n', file); + } +} + + +static void +loop_biv_dump (v, file, verbose) + const struct induction *v; + FILE *file; + int verbose; +{ + if (! v || ! file) + return; + + fprintf (file, + "Biv %d: insn %d", + REGNO (v->dest_reg), INSN_UID (v->insn)); + fprintf (file, " const "); + print_simple_rtl (file, v->add_val); + + if (verbose && v->final_value) + { + fputc ('\n', file); + fprintf (file, " final "); + print_simple_rtl (file, v->final_value); + } + + fputc ('\n', file); +} + + +static void +loop_giv_dump (v, file, verbose) + const struct induction *v; + FILE *file; + int verbose; +{ + if (! v || ! file) + return; + + if (v->giv_type == DEST_REG) + fprintf (file, "Giv %d: insn %d", + REGNO (v->dest_reg), INSN_UID (v->insn)); + else + fprintf (file, "Dest address: insn %d", + INSN_UID (v->insn)); + + fprintf (file, " src reg %d benefit %d", + REGNO (v->src_reg), v->benefit); + fprintf (file, " lifetime %d", + v->lifetime); + + if (v->replaceable) + fprintf (file, " replaceable"); + + if (v->no_const_addval) + fprintf (file, " ncav"); + + if (v->ext_dependent) + { + switch (GET_CODE (v->ext_dependent)) + { + case SIGN_EXTEND: + fprintf (file, " ext se"); + break; + case ZERO_EXTEND: + fprintf (file, " ext ze"); + break; + case TRUNCATE: + fprintf (file, " ext tr"); + break; + default: + abort (); + } + } + + fputc ('\n', file); + fprintf (file, " mult "); + print_simple_rtl (file, v->mult_val); + + fputc ('\n', file); + fprintf (file, " add "); + print_simple_rtl (file, v->add_val); + + if (verbose && v->final_value) + { + fputc ('\n', file); + fprintf (file, " final "); + print_simple_rtl (file, v->final_value); + } + + fputc ('\n', file); +} + + +void +debug_ivs (loop) + const struct loop *loop; +{ + loop_ivs_dump (loop, stderr, 1); +} + + +void +debug_iv_class (bl) + const struct iv_class *bl; +{ + loop_iv_class_dump (bl, stderr, 1); +} + + +void +debug_biv (v) + const struct induction *v; +{ + loop_biv_dump (v, stderr, 1); +} + + +void +debug_giv (v) + const struct induction *v; +{ + loop_giv_dump (v, stderr, 1); +} + + +#define LOOP_BLOCK_NUM_1(INSN) \ +((INSN) ? (BLOCK_FOR_INSN (INSN) ? BLOCK_NUM (INSN) : - 1) : -1) + +/* The notes do not have an assigned block, so look at the next insn. */ +#define LOOP_BLOCK_NUM(INSN) \ +((INSN) ? (GET_CODE (INSN) == NOTE \ + ? LOOP_BLOCK_NUM_1 (next_nonnote_insn (INSN)) \ + : LOOP_BLOCK_NUM_1 (INSN)) \ + : -1) + +#define LOOP_INSN_UID(INSN) ((INSN) ? INSN_UID (INSN) : -1) + +static void +loop_dump_aux (loop, file, verbose) + const struct loop *loop; + FILE *file; + int verbose ATTRIBUTE_UNUSED; +{ + rtx label; + + if (! loop || ! file) + return; + + /* Print diagnostics to compare our concept of a loop with + what the loop notes say. */ + if (! PREV_INSN (loop->first->head) + || GET_CODE (PREV_INSN (loop->first->head)) != NOTE + || NOTE_LINE_NUMBER (PREV_INSN (loop->first->head)) + != NOTE_INSN_LOOP_BEG) + fprintf (file, ";; No NOTE_INSN_LOOP_BEG at %d\n", + INSN_UID (PREV_INSN (loop->first->head))); + if (! NEXT_INSN (loop->last->end) + || GET_CODE (NEXT_INSN (loop->last->end)) != NOTE + || NOTE_LINE_NUMBER (NEXT_INSN (loop->last->end)) + != NOTE_INSN_LOOP_END) + fprintf (file, ";; No NOTE_INSN_LOOP_END at %d\n", + INSN_UID (NEXT_INSN (loop->last->end))); + + if (loop->start) + { + fprintf (file, + ";; start %d (%d), cont dom %d (%d), cont %d (%d), vtop %d (%d), end %d (%d)\n", + LOOP_BLOCK_NUM (loop->start), + LOOP_INSN_UID (loop->start), + LOOP_BLOCK_NUM (loop->cont), + LOOP_INSN_UID (loop->cont), + LOOP_BLOCK_NUM (loop->cont), + LOOP_INSN_UID (loop->cont), + LOOP_BLOCK_NUM (loop->vtop), + LOOP_INSN_UID (loop->vtop), + LOOP_BLOCK_NUM (loop->end), + LOOP_INSN_UID (loop->end)); + fprintf (file, ";; top %d (%d), scan start %d (%d)\n", + LOOP_BLOCK_NUM (loop->top), + LOOP_INSN_UID (loop->top), + LOOP_BLOCK_NUM (loop->scan_start), + LOOP_INSN_UID (loop->scan_start)); + fprintf (file, ";; exit_count %d", loop->exit_count); + if (loop->exit_count) + { + fputs (", labels:", file); + for (label = loop->exit_labels; label; label = LABEL_NEXTREF (label)) + { + fprintf (file, " %d ", + LOOP_INSN_UID (XEXP (label, 0))); + } + } + fputs ("\n", file); + + /* This can happen when a marked loop appears as two nested loops, + say from while (a || b) {}. The inner loop won't match + the loop markers but the outer one will. */ + if (LOOP_BLOCK_NUM (loop->cont) != loop->latch->index) + fprintf (file, ";; NOTE_INSN_LOOP_CONT not in loop latch\n"); + } +} + +/* Call this function from the debugger to dump LOOP. */ + +void +debug_loop (loop) + const struct loop *loop; +{ + flow_loop_dump (loop, stderr, loop_dump_aux, 1); +} + +/* Call this function from the debugger to dump LOOPS. */ + +void +debug_loops (loops) + const struct loops *loops; +{ + flow_loops_dump (loops, stderr, loop_dump_aux, 1); +} |
