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Diffstat (limited to 'contrib/gcc/loop.h')
| -rw-r--r-- | contrib/gcc/loop.h | 432 |
1 files changed, 0 insertions, 432 deletions
diff --git a/contrib/gcc/loop.h b/contrib/gcc/loop.h deleted file mode 100644 index f2f870c..0000000 --- a/contrib/gcc/loop.h +++ /dev/null @@ -1,432 +0,0 @@ -/* Loop optimization definitions for GCC - Copyright (C) 1991, 1995, 1998, 1999, 2000, 2001, 2002, 2003, 2004 - Free Software Foundation, Inc. - -This file is part of GCC. - -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. - -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 GCC; see the file COPYING. If not, write to the Free -Software Foundation, 59 Temple Place - Suite 330, Boston, MA -02111-1307, USA. */ - -#include "bitmap.h" -#include "sbitmap.h" -#include "hard-reg-set.h" -#include "basic-block.h" - -/* Flags passed to loop_optimize. */ -#define LOOP_UNROLL 1 -#define LOOP_BCT 2 -#define LOOP_PREFETCH 4 -#define LOOP_AUTO_UNROLL 8 - -/* Get the loop info pointer of a loop. */ -#define LOOP_INFO(LOOP) ((struct loop_info *) (LOOP)->aux) - -/* Get a pointer to the loop movables structure. */ -#define LOOP_MOVABLES(LOOP) (&LOOP_INFO (LOOP)->movables) - -/* Get a pointer to the loop registers structure. */ -#define LOOP_REGS(LOOP) (&LOOP_INFO (LOOP)->regs) - -/* Get a pointer to the loop induction variables structure. */ -#define LOOP_IVS(LOOP) (&LOOP_INFO (LOOP)->ivs) - -/* Get the luid of an insn. Catch the error of trying to reference the LUID - of an insn added during loop, since these don't have LUIDs. */ - -#define INSN_LUID(INSN) \ - (INSN_UID (INSN) < max_uid_for_loop ? uid_luid[INSN_UID (INSN)] \ - : (abort (), -1)) - -#define REGNO_FIRST_LUID(REGNO) \ - (REGNO_FIRST_UID (REGNO) < max_uid_for_loop \ - ? uid_luid[REGNO_FIRST_UID (REGNO)] \ - : 0) -#define REGNO_LAST_LUID(REGNO) \ - (REGNO_LAST_UID (REGNO) < max_uid_for_loop \ - ? uid_luid[REGNO_LAST_UID (REGNO)] \ - : INT_MAX) - -/* 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'. */ - -/* An enum for the two different types of givs, those that are used - as memory addresses and those that are calculated into registers. */ -enum g_types -{ - DEST_ADDR, - DEST_REG -}; - - -/* A `struct induction' is created for every instruction that sets - an induction variable (either a biv or a giv). */ - -struct induction -{ - rtx insn; /* The insn that sets a biv or giv */ - rtx new_reg; /* New register, containing strength reduced - version of this giv. */ - rtx src_reg; /* Biv from which this giv is computed. - (If this is a biv, then this is the biv.) */ - enum g_types giv_type; /* Indicate whether DEST_ADDR or DEST_REG */ - rtx dest_reg; /* Destination register for insn: this is the - register which was the biv or giv. - For a biv, this equals src_reg. - For a DEST_ADDR type giv, this is 0. */ - rtx *location; /* Place in the insn where this giv occurs. - If GIV_TYPE is DEST_REG, this is 0. */ - /* For a biv, this is the place where add_val - was found. */ - enum machine_mode mode; /* The mode of this biv or giv */ - rtx mem; /* For DEST_ADDR, the memory object. */ - rtx mult_val; /* Multiplicative factor for src_reg. */ - rtx add_val; /* Additive constant for that product. */ - int benefit; /* Gain from eliminating this insn. */ - rtx final_value; /* If the giv is used outside the loop, and its - final value could be calculated, it is put - here, and the giv is made replaceable. Set - the giv to this value before the loop. */ - unsigned combined_with; /* The number of givs this giv has been - combined with. If nonzero, this giv - cannot combine with any other giv. */ - unsigned replaceable : 1; /* 1 if we can substitute the strength-reduced - variable for the original variable. - 0 means they must be kept separate and the - new one must be copied into the old pseudo - reg each time the old one is set. */ - unsigned not_replaceable : 1; /* Used to prevent duplicating work. This is - 1 if we know that the giv definitely can - not be made replaceable, in which case we - don't bother checking the variable again - even if further info is available. - Both this and the above can be zero. */ - unsigned ignore : 1; /* 1 prohibits further processing of giv */ - unsigned always_computable : 1;/* 1 if this value is computable every - iteration. */ - unsigned always_executed : 1; /* 1 if this set occurs each iteration. */ - unsigned maybe_multiple : 1; /* Only used for a biv and 1 if this biv - update may be done multiple times per - iteration. */ - unsigned cant_derive : 1; /* For giv's, 1 if this giv cannot derive - another giv. This occurs in many cases - where a giv's lifetime spans an update to - a biv. */ - unsigned maybe_dead : 1; /* 1 if this giv might be dead. In that case, - we won't use it to eliminate a biv, it - would probably lose. */ - unsigned auto_inc_opt : 1; /* 1 if this giv had its increment output next - to it to try to form an auto-inc address. */ - unsigned unrolled : 1; /* 1 if new register has been allocated and - initialized in unrolled loop. */ - unsigned shared : 1; - unsigned no_const_addval : 1; /* 1 if add_val does not contain a const. */ - int lifetime; /* Length of life of this giv */ - rtx derive_adjustment; /* If nonzero, is an adjustment to be - subtracted from add_val when this giv - derives another. This occurs when the - giv spans a biv update by incrementation. */ - rtx ext_dependent; /* If nonzero, is a sign or zero extension - if a biv on which this giv is dependent. */ - struct induction *next_iv; /* For givs, links together all givs that are - based on the same biv. For bivs, links - together all biv entries that refer to the - same biv register. */ - struct induction *same; /* For givs, if the giv has been combined with - another giv, this points to the base giv. - The base giv will have COMBINED_WITH nonzero. - For bivs, if the biv has the same LOCATION - than another biv, this points to the base - biv. */ - HOST_WIDE_INT const_adjust; /* Used by loop unrolling, when an address giv - is split, and a constant is eliminated from - the address, the -constant is stored here - for later use. */ - struct induction *same_insn; /* If there are multiple identical givs in - the same insn, then all but one have this - field set, and they all point to the giv - that doesn't have this field set. */ - rtx last_use; /* For a giv made from a biv increment, this is - a substitute for the lifetime information. */ -}; - - -/* A `struct iv_class' is created for each biv. */ - -struct iv_class -{ - unsigned int regno; /* Pseudo reg which is the biv. */ - int biv_count; /* Number of insns setting this reg. */ - struct induction *biv; /* List of all insns that set this reg. */ - int giv_count; /* Number of DEST_REG givs computed from this - biv. The resulting count is only used in - check_dbra_loop. */ - struct induction *giv; /* List of all insns that compute a giv - from this reg. */ - int total_benefit; /* Sum of BENEFITs of all those givs. */ - rtx initial_value; /* Value of reg at loop start. */ - rtx initial_test; /* Test performed on BIV before loop. */ - rtx final_value; /* Value of reg at loop end, if known. */ - struct iv_class *next; /* Links all class structures together. */ - rtx init_insn; /* insn which initializes biv, 0 if none. */ - rtx init_set; /* SET of INIT_INSN, if any. */ - unsigned incremented : 1; /* 1 if somewhere incremented/decremented */ - unsigned eliminable : 1; /* 1 if plausible candidate for - elimination. */ - unsigned nonneg : 1; /* 1 if we added a REG_NONNEG note for - this. */ - unsigned reversed : 1; /* 1 if we reversed the loop that this - biv controls. */ - unsigned all_reduced : 1; /* 1 if all givs using this biv have - been reduced. */ -}; - - -/* Definitions used by the basic induction variable discovery code. */ -enum iv_mode -{ - UNKNOWN_INDUCT, - BASIC_INDUCT, - NOT_BASIC_INDUCT, - GENERAL_INDUCT -}; - - -/* A `struct iv' is created for every register. */ - -struct iv -{ - enum iv_mode type; - union - { - struct iv_class *class; - struct induction *info; - } iv; -}; - - -#define REG_IV_TYPE(ivs, n) ivs->regs[n].type -#define REG_IV_INFO(ivs, n) ivs->regs[n].iv.info -#define REG_IV_CLASS(ivs, n) ivs->regs[n].iv.class - - -struct loop_ivs -{ - /* Indexed by register number, contains pointer to `struct - iv' if register is an induction variable. */ - struct iv *regs; - - /* Size of regs array. */ - unsigned int n_regs; - - /* The head of a list which links together (via the next field) - every iv class for the current loop. */ - struct iv_class *list; -}; - - -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; - - - -struct loop_reg -{ - /* 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 a 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. */ - int set_in_loop; - - /* 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. */ - int n_times_set; - - /* 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. */ - rtx single_usage; - - /* Nonzero indicates that the register cannot be moved or strength - reduced. */ - char may_not_optimize; - - /* Nonzero means reg N has already been moved out of one loop. - This reduces the desire to move it out of another. */ - char moved_once; -}; - - -struct loop_regs -{ - int num; /* Number of regs used in table. */ - int size; /* Size of table. */ - struct loop_reg *array; /* Register usage info. array. */ - int multiple_uses; /* Nonzero if a reg has multiple uses. */ -}; - - - -struct loop_movables -{ - /* Head of movable chain. */ - struct movable *head; - /* Last movable in chain. */ - struct movable *last; -}; - - -/* Information pertaining to a loop. */ - -struct loop_info -{ - /* Nonzero if there is a subroutine call in the current loop. */ - int has_call; - /* Nonzero if there is a libcall in the current loop. */ - int has_libcall; - /* Nonzero if there is a non constant call in the current loop. */ - int has_nonconst_call; - /* Nonzero if there is a prefetch instruction in the current loop. */ - int has_prefetch; - /* Nonzero if there is a volatile memory reference in the current - loop. */ - int has_volatile; - /* Nonzero if there is a tablejump in the current loop. */ - int has_tablejump; - /* Nonzero if there are ways to leave the loop other than falling - off the end. */ - int has_multiple_exit_targets; - /* Nonzero if there is an indirect jump in the current function. */ - int has_indirect_jump; - /* Whether loop unrolling has emitted copies of the loop body so - that the main loop needs no exit tests. */ - int preconditioned; - /* Register or constant initial loop value. */ - rtx initial_value; - /* Register or constant value used for comparison test. */ - rtx comparison_value; - /* Register or constant approximate final value. */ - rtx final_value; - /* Register or constant initial loop value with term common to - final_value removed. */ - rtx initial_equiv_value; - /* Register or constant final loop value with term common to - initial_value removed. */ - rtx final_equiv_value; - /* Register corresponding to iteration variable. */ - rtx iteration_var; - /* Constant loop increment. */ - rtx increment; - enum rtx_code comparison_code; - /* Holds the number of loop iterations. It is zero if the number - could not be calculated. Must be unsigned since the number of - iterations can be as high as 2^wordsize - 1. For loops with a - wider iterator, this number will be zero if the number of loop - iterations is too large for an unsigned integer to hold. */ - unsigned HOST_WIDE_INT n_iterations; - /* The number of times the loop body was unrolled. */ - unsigned int unroll_number; - int used_count_register; - /* The loop iterator induction variable. */ - struct iv_class *iv; - /* List of MEMs that are stored in this loop. */ - rtx store_mems; - /* 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 mems[i] is altered during - the loop, it is altered by an expression that is rtx_equal_p to - it. */ - loop_mem_info *mems; - /* The index of the next available slot in MEMS. */ - int mems_idx; - /* The number of elements allocated in MEMS. */ - int mems_allocated; - /* 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 - `has_call' will also be set) or if we store into more than - NUM_STORES MEMs. */ - int unknown_address_altered; - /* The above doesn't count any readonly memory locations that are - stored. This does. */ - int unknown_constant_address_altered; - /* Count of memory write instructions discovered in the loop. */ - int num_mem_sets; - /* The insn where the first of these was found. */ - rtx first_loop_store_insn; - /* The chain of movable insns in loop. */ - struct loop_movables movables; - /* The registers used the in loop. */ - struct loop_regs regs; - /* The induction variable information in loop. */ - struct loop_ivs ivs; - /* Nonzero if call is in pre_header extended basic block. */ - int pre_header_has_call; -}; - - -/* Variables declared in loop.c, but also needed in unroll.c. */ - -extern int *uid_luid; -extern int max_uid_for_loop; -extern unsigned int max_reg_before_loop; -extern struct loop **uid_loop; -extern FILE *loop_dump_stream; - - -/* Forward declarations for non-static functions declared in loop.c and - unroll.c. */ -extern int loop_invariant_p (const struct loop *, rtx); -extern rtx get_condition_for_loop (const struct loop *, rtx); -extern void loop_iv_add_mult_hoist (const struct loop *, rtx, rtx, rtx, rtx); -extern void loop_iv_add_mult_sink (const struct loop *, rtx, rtx, rtx, rtx); -extern void loop_iv_add_mult_emit_before (const struct loop *, rtx, rtx, - rtx, rtx, basic_block, rtx); -extern rtx express_from (struct induction *, struct induction *); -extern rtx extend_value_for_giv (struct induction *, rtx); - -extern void unroll_loop (struct loop *, int, int); -extern rtx biv_total_increment (const struct iv_class *); -extern unsigned HOST_WIDE_INT loop_iterations (struct loop *); -extern int precondition_loop_p (const struct loop *, rtx *, rtx *, rtx *, - enum machine_mode *mode); -extern rtx final_biv_value (const struct loop *, struct iv_class *); -extern rtx final_giv_value (const struct loop *, struct induction *); -extern void emit_unrolled_add (rtx, rtx, rtx); -extern int back_branch_in_range_p (const struct loop *, rtx); - -extern int loop_insn_first_p (rtx, rtx); -typedef rtx (*loop_insn_callback) (struct loop *, rtx, int, int); -extern void for_each_insn_in_loop (struct loop *, loop_insn_callback); -extern rtx loop_insn_emit_before (const struct loop *, basic_block, rtx, rtx); -extern rtx loop_insn_sink (const struct loop *, rtx); -extern rtx loop_insn_hoist (const struct loop *, rtx); - -/* Forward declarations for non-static functions declared in doloop.c. */ -extern rtx doloop_condition_get (rtx); -extern int doloop_optimize (const struct loop *); |
