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Diffstat (limited to 'gnu/usr.bin/cc/cc_int/global.c')
| -rw-r--r-- | gnu/usr.bin/cc/cc_int/global.c | 1713 |
1 files changed, 0 insertions, 1713 deletions
diff --git a/gnu/usr.bin/cc/cc_int/global.c b/gnu/usr.bin/cc/cc_int/global.c deleted file mode 100644 index 650fb5f..0000000 --- a/gnu/usr.bin/cc/cc_int/global.c +++ /dev/null @@ -1,1713 +0,0 @@ -/* Allocate registers for pseudo-registers that span basic blocks. - Copyright (C) 1987, 1988, 1991, 1994 Free Software Foundation, Inc. - -This file is part of GNU CC. - -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. - -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. - -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, 675 Mass Ave, Cambridge, MA 02139, USA. */ - - -#include <stdio.h> -#include "config.h" -#include "rtl.h" -#include "flags.h" -#include "basic-block.h" -#include "hard-reg-set.h" -#include "regs.h" -#include "insn-config.h" -#include "output.h" - -/* This pass of the compiler performs global register allocation. - It assigns hard register numbers to all the pseudo registers - that were not handled in local_alloc. Assignments are recorded - in the vector reg_renumber, not by changing the rtl code. - (Such changes are made by final). The entry point is - the function global_alloc. - - After allocation is complete, the reload pass is run as a subroutine - of this pass, so that when a pseudo reg loses its hard reg due to - spilling it is possible to make a second attempt to find a hard - reg for it. The reload pass is independent in other respects - and it is run even when stupid register allocation is in use. - - 1. count the pseudo-registers still needing allocation - and assign allocation-numbers (allocnos) to them. - Set up tables reg_allocno and allocno_reg to map - reg numbers to allocnos and vice versa. - max_allocno gets the number of allocnos in use. - - 2. Allocate a max_allocno by max_allocno conflict bit matrix and clear it. - Allocate a max_allocno by FIRST_PSEUDO_REGISTER conflict matrix - for conflicts between allocnos and explicit hard register use - (which includes use of pseudo-registers allocated by local_alloc). - - 3. for each basic block - walk forward through the block, recording which - unallocated registers and which hardware registers are live. - Build the conflict matrix between the unallocated registers - and another of unallocated registers versus hardware registers. - Also record the preferred hardware registers - for each unallocated one. - - 4. Sort a table of the allocnos into order of - desirability of the variables. - - 5. Allocate the variables in that order; each if possible into - a preferred register, else into another register. */ - -/* Number of pseudo-registers still requiring allocation - (not allocated by local_allocate). */ - -static int max_allocno; - -/* Indexed by (pseudo) reg number, gives the allocno, or -1 - for pseudo registers already allocated by local_allocate. */ - -static int *reg_allocno; - -/* Indexed by allocno, gives the reg number. */ - -static int *allocno_reg; - -/* A vector of the integers from 0 to max_allocno-1, - sorted in the order of first-to-be-allocated first. */ - -static int *allocno_order; - -/* Indexed by an allocno, gives the number of consecutive - hard registers needed by that pseudo reg. */ - -static int *allocno_size; - -/* Indexed by (pseudo) reg number, gives the number of another - lower-numbered pseudo reg which can share a hard reg with this pseudo - *even if the two pseudos would otherwise appear to conflict*. */ - -static int *reg_may_share; - -/* Define the number of bits in each element of `conflicts' and what - type that element has. We use the largest integer format on the - host machine. */ - -#define INT_BITS HOST_BITS_PER_WIDE_INT -#define INT_TYPE HOST_WIDE_INT - -/* max_allocno by max_allocno array of bits, - recording whether two allocno's conflict (can't go in the same - hardware register). - - `conflicts' is not symmetric; a conflict between allocno's i and j - is recorded either in element i,j or in element j,i. */ - -static INT_TYPE *conflicts; - -/* Number of ints require to hold max_allocno bits. - This is the length of a row in `conflicts'. */ - -static int allocno_row_words; - -/* Two macros to test or store 1 in an element of `conflicts'. */ - -#define CONFLICTP(I, J) \ - (conflicts[(I) * allocno_row_words + (J) / INT_BITS] \ - & ((INT_TYPE) 1 << ((J) % INT_BITS))) - -#define SET_CONFLICT(I, J) \ - (conflicts[(I) * allocno_row_words + (J) / INT_BITS] \ - |= ((INT_TYPE) 1 << ((J) % INT_BITS))) - -/* Set of hard regs currently live (during scan of all insns). */ - -static HARD_REG_SET hard_regs_live; - -/* Indexed by N, set of hard regs conflicting with allocno N. */ - -static HARD_REG_SET *hard_reg_conflicts; - -/* Indexed by N, set of hard regs preferred by allocno N. - This is used to make allocnos go into regs that are copied to or from them, - when possible, to reduce register shuffling. */ - -static HARD_REG_SET *hard_reg_preferences; - -/* Similar, but just counts register preferences made in simple copy - operations, rather than arithmetic. These are given priority because - we can always eliminate an insn by using these, but using a register - in the above list won't always eliminate an insn. */ - -static HARD_REG_SET *hard_reg_copy_preferences; - -/* Similar to hard_reg_preferences, but includes bits for subsequent - registers when an allocno is multi-word. The above variable is used for - allocation while this is used to build reg_someone_prefers, below. */ - -static HARD_REG_SET *hard_reg_full_preferences; - -/* Indexed by N, set of hard registers that some later allocno has a - preference for. */ - -static HARD_REG_SET *regs_someone_prefers; - -/* Set of registers that global-alloc isn't supposed to use. */ - -static HARD_REG_SET no_global_alloc_regs; - -/* Set of registers used so far. */ - -static HARD_REG_SET regs_used_so_far; - -/* Number of calls crossed by each allocno. */ - -static int *allocno_calls_crossed; - -/* Number of refs (weighted) to each allocno. */ - -static int *allocno_n_refs; - -/* Guess at live length of each allocno. - This is actually the max of the live lengths of the regs. */ - -static int *allocno_live_length; - -/* Number of refs (weighted) to each hard reg, as used by local alloc. - It is zero for a reg that contains global pseudos or is explicitly used. */ - -static int local_reg_n_refs[FIRST_PSEUDO_REGISTER]; - -/* Guess at live length of each hard reg, as used by local alloc. - This is actually the sum of the live lengths of the specific regs. */ - -static int local_reg_live_length[FIRST_PSEUDO_REGISTER]; - -/* Test a bit in TABLE, a vector of HARD_REG_SETs, - for vector element I, and hard register number J. */ - -#define REGBITP(TABLE, I, J) TEST_HARD_REG_BIT (TABLE[I], J) - -/* Set to 1 a bit in a vector of HARD_REG_SETs. Works like REGBITP. */ - -#define SET_REGBIT(TABLE, I, J) SET_HARD_REG_BIT (TABLE[I], J) - -/* Bit mask for allocnos live at current point in the scan. */ - -static INT_TYPE *allocnos_live; - -/* Test, set or clear bit number I in allocnos_live, - a bit vector indexed by allocno. */ - -#define ALLOCNO_LIVE_P(I) \ - (allocnos_live[(I) / INT_BITS] & ((INT_TYPE) 1 << ((I) % INT_BITS))) - -#define SET_ALLOCNO_LIVE(I) \ - (allocnos_live[(I) / INT_BITS] |= ((INT_TYPE) 1 << ((I) % INT_BITS))) - -#define CLEAR_ALLOCNO_LIVE(I) \ - (allocnos_live[(I) / INT_BITS] &= ~((INT_TYPE) 1 << ((I) % INT_BITS))) - -/* This is turned off because it doesn't work right for DImode. - (And it is only used for DImode, so the other cases are worthless.) - The problem is that it isn't true that there is NO possibility of conflict; - only that there is no conflict if the two pseudos get the exact same regs. - If they were allocated with a partial overlap, there would be a conflict. - We can't safely turn off the conflict unless we have another way to - prevent the partial overlap. - - Idea: change hard_reg_conflicts so that instead of recording which - hard regs the allocno may not overlap, it records where the allocno - may not start. Change both where it is used and where it is updated. - Then there is a way to record that (reg:DI 108) may start at 10 - but not at 9 or 11. There is still the question of how to record - this semi-conflict between two pseudos. */ -#if 0 -/* Reg pairs for which conflict after the current insn - is inhibited by a REG_NO_CONFLICT note. - If the table gets full, we ignore any other notes--that is conservative. */ -#define NUM_NO_CONFLICT_PAIRS 4 -/* Number of pairs in use in this insn. */ -int n_no_conflict_pairs; -static struct { int allocno1, allocno2;} - no_conflict_pairs[NUM_NO_CONFLICT_PAIRS]; -#endif /* 0 */ - -/* Record all regs that are set in any one insn. - Communication from mark_reg_{store,clobber} and global_conflicts. */ - -static rtx *regs_set; -static int n_regs_set; - -/* All registers that can be eliminated. */ - -static HARD_REG_SET eliminable_regset; - -static int allocno_compare PROTO((int *, int *)); -static void global_conflicts PROTO((void)); -static void expand_preferences PROTO((void)); -static void prune_preferences PROTO((void)); -static void find_reg PROTO((int, HARD_REG_SET, int, int, int)); -static void record_one_conflict PROTO((int)); -static void record_conflicts PROTO((short *, int)); -static void mark_reg_store PROTO((rtx, rtx)); -static void mark_reg_clobber PROTO((rtx, rtx)); -static void mark_reg_conflicts PROTO((rtx)); -static void mark_reg_death PROTO((rtx)); -static void mark_reg_live_nc PROTO((int, enum machine_mode)); -static void set_preference PROTO((rtx, rtx)); -static void dump_conflicts PROTO((FILE *)); - -/* Perform allocation of pseudo-registers not allocated by local_alloc. - FILE is a file to output debugging information on, - or zero if such output is not desired. - - Return value is nonzero if reload failed - and we must not do any more for this function. */ - -int -global_alloc (file) - FILE *file; -{ -#ifdef ELIMINABLE_REGS - static struct {int from, to; } eliminables[] = ELIMINABLE_REGS; -#endif - int need_fp - = (! flag_omit_frame_pointer -#ifdef EXIT_IGNORE_STACK - || (current_function_calls_alloca && EXIT_IGNORE_STACK) -#endif - || FRAME_POINTER_REQUIRED); - - register int i; - rtx x; - - max_allocno = 0; - - /* A machine may have certain hard registers that - are safe to use only within a basic block. */ - - CLEAR_HARD_REG_SET (no_global_alloc_regs); -#ifdef OVERLAPPING_REGNO_P - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (OVERLAPPING_REGNO_P (i)) - SET_HARD_REG_BIT (no_global_alloc_regs, i); -#endif - - /* Build the regset of all eliminable registers and show we can't use those - that we already know won't be eliminated. */ -#ifdef ELIMINABLE_REGS - for (i = 0; i < sizeof eliminables / sizeof eliminables[0]; i++) - { - SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from); - - if (! CAN_ELIMINATE (eliminables[i].from, eliminables[i].to) - || (eliminables[i].to == STACK_POINTER_REGNUM && need_fp)) - SET_HARD_REG_BIT (no_global_alloc_regs, eliminables[i].from); - } -#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM - SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM); - if (need_fp) - SET_HARD_REG_BIT (no_global_alloc_regs, HARD_FRAME_POINTER_REGNUM); -#endif - -#else - SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM); - if (need_fp) - SET_HARD_REG_BIT (no_global_alloc_regs, FRAME_POINTER_REGNUM); -#endif - - /* Track which registers have already been used. Start with registers - explicitly in the rtl, then registers allocated by local register - allocation. */ - - CLEAR_HARD_REG_SET (regs_used_so_far); -#ifdef LEAF_REGISTERS - /* If we are doing the leaf function optimization, and this is a leaf - function, it means that the registers that take work to save are those - that need a register window. So prefer the ones that can be used in - a leaf function. */ - { - char *cheap_regs; - static char leaf_regs[] = LEAF_REGISTERS; - - if (only_leaf_regs_used () && leaf_function_p ()) - cheap_regs = leaf_regs; - else - cheap_regs = call_used_regs; - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (regs_ever_live[i] || cheap_regs[i]) - SET_HARD_REG_BIT (regs_used_so_far, i); - } -#else - /* We consider registers that do not have to be saved over calls as if - they were already used since there is no cost in using them. */ - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (regs_ever_live[i] || call_used_regs[i]) - SET_HARD_REG_BIT (regs_used_so_far, i); -#endif - - for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) - if (reg_renumber[i] >= 0) - SET_HARD_REG_BIT (regs_used_so_far, reg_renumber[i]); - - /* Establish mappings from register number to allocation number - and vice versa. In the process, count the allocnos. */ - - reg_allocno = (int *) alloca (max_regno * sizeof (int)); - - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - reg_allocno[i] = -1; - - /* Initialize the shared-hard-reg mapping - from the list of pairs that may share. */ - reg_may_share = (int *) alloca (max_regno * sizeof (int)); - bzero ((char *) reg_may_share, max_regno * sizeof (int)); - for (x = regs_may_share; x; x = XEXP (XEXP (x, 1), 1)) - { - int r1 = REGNO (XEXP (x, 0)); - int r2 = REGNO (XEXP (XEXP (x, 1), 0)); - if (r1 > r2) - reg_may_share[r1] = r2; - else - reg_may_share[r2] = r1; - } - - for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) - /* Note that reg_live_length[i] < 0 indicates a "constant" reg - that we are supposed to refrain from putting in a hard reg. - -2 means do make an allocno but don't allocate it. */ - if (reg_n_refs[i] != 0 && reg_renumber[i] < 0 && reg_live_length[i] != -1 - /* Don't allocate pseudos that cross calls, - if this function receives a nonlocal goto. */ - && (! current_function_has_nonlocal_label - || reg_n_calls_crossed[i] == 0)) - { - if (reg_may_share[i] && reg_allocno[reg_may_share[i]] >= 0) - reg_allocno[i] = reg_allocno[reg_may_share[i]]; - else - reg_allocno[i] = max_allocno++; - if (reg_live_length[i] == 0) - abort (); - } - else - reg_allocno[i] = -1; - - allocno_reg = (int *) alloca (max_allocno * sizeof (int)); - allocno_size = (int *) alloca (max_allocno * sizeof (int)); - allocno_calls_crossed = (int *) alloca (max_allocno * sizeof (int)); - allocno_n_refs = (int *) alloca (max_allocno * sizeof (int)); - allocno_live_length = (int *) alloca (max_allocno * sizeof (int)); - bzero ((char *) allocno_size, max_allocno * sizeof (int)); - bzero ((char *) allocno_calls_crossed, max_allocno * sizeof (int)); - bzero ((char *) allocno_n_refs, max_allocno * sizeof (int)); - bzero ((char *) allocno_live_length, max_allocno * sizeof (int)); - - for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) - if (reg_allocno[i] >= 0) - { - int allocno = reg_allocno[i]; - allocno_reg[allocno] = i; - allocno_size[allocno] = PSEUDO_REGNO_SIZE (i); - allocno_calls_crossed[allocno] += reg_n_calls_crossed[i]; - allocno_n_refs[allocno] += reg_n_refs[i]; - if (allocno_live_length[allocno] < reg_live_length[i]) - allocno_live_length[allocno] = reg_live_length[i]; - } - - /* Calculate amount of usage of each hard reg by pseudos - allocated by local-alloc. This is to see if we want to - override it. */ - bzero ((char *) local_reg_live_length, sizeof local_reg_live_length); - bzero ((char *) local_reg_n_refs, sizeof local_reg_n_refs); - for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) - if (reg_allocno[i] < 0 && reg_renumber[i] >= 0) - { - int regno = reg_renumber[i]; - int endregno = regno + HARD_REGNO_NREGS (regno, PSEUDO_REGNO_MODE (i)); - int j; - - for (j = regno; j < endregno; j++) - { - local_reg_n_refs[j] += reg_n_refs[i]; - local_reg_live_length[j] += reg_live_length[i]; - } - } - - /* We can't override local-alloc for a reg used not just by local-alloc. */ - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (regs_ever_live[i]) - local_reg_n_refs[i] = 0; - - /* Likewise for regs used in a SCRATCH. */ - for (i = 0; i < scratch_list_length; i++) - if (scratch_list[i]) - { - int regno = REGNO (scratch_list[i]); - int lim = regno + HARD_REGNO_NREGS (regno, GET_MODE (scratch_list[i])); - int j; - - for (j = regno; j < lim; j++) - local_reg_n_refs[j] = 0; - } - - /* Allocate the space for the conflict and preference tables and - initialize them. */ - - hard_reg_conflicts - = (HARD_REG_SET *) alloca (max_allocno * sizeof (HARD_REG_SET)); - bzero ((char *) hard_reg_conflicts, max_allocno * sizeof (HARD_REG_SET)); - - hard_reg_preferences - = (HARD_REG_SET *) alloca (max_allocno * sizeof (HARD_REG_SET)); - bzero ((char *) hard_reg_preferences, max_allocno * sizeof (HARD_REG_SET)); - - hard_reg_copy_preferences - = (HARD_REG_SET *) alloca (max_allocno * sizeof (HARD_REG_SET)); - bzero ((char *) hard_reg_copy_preferences, - max_allocno * sizeof (HARD_REG_SET)); - - hard_reg_full_preferences - = (HARD_REG_SET *) alloca (max_allocno * sizeof (HARD_REG_SET)); - bzero ((char *) hard_reg_full_preferences, - max_allocno * sizeof (HARD_REG_SET)); - - regs_someone_prefers - = (HARD_REG_SET *) alloca (max_allocno * sizeof (HARD_REG_SET)); - bzero ((char *) regs_someone_prefers, max_allocno * sizeof (HARD_REG_SET)); - - allocno_row_words = (max_allocno + INT_BITS - 1) / INT_BITS; - - conflicts = (INT_TYPE *) alloca (max_allocno * allocno_row_words - * sizeof (INT_TYPE)); - bzero ((char *) conflicts, - max_allocno * allocno_row_words * sizeof (INT_TYPE)); - - allocnos_live = (INT_TYPE *) alloca (allocno_row_words * sizeof (INT_TYPE)); - - /* If there is work to be done (at least one reg to allocate), - perform global conflict analysis and allocate the regs. */ - - if (max_allocno > 0) - { - /* Scan all the insns and compute the conflicts among allocnos - and between allocnos and hard regs. */ - - global_conflicts (); - - /* Eliminate conflicts between pseudos and eliminable registers. If - the register is not eliminated, the pseudo won't really be able to - live in the eliminable register, so the conflict doesn't matter. - If we do eliminate the register, the conflict will no longer exist. - So in either case, we can ignore the conflict. Likewise for - preferences. */ - - for (i = 0; i < max_allocno; i++) - { - AND_COMPL_HARD_REG_SET (hard_reg_conflicts[i], eliminable_regset); - AND_COMPL_HARD_REG_SET (hard_reg_copy_preferences[i], - eliminable_regset); - AND_COMPL_HARD_REG_SET (hard_reg_preferences[i], eliminable_regset); - } - - /* Try to expand the preferences by merging them between allocnos. */ - - expand_preferences (); - - /* Determine the order to allocate the remaining pseudo registers. */ - - allocno_order = (int *) alloca (max_allocno * sizeof (int)); - for (i = 0; i < max_allocno; i++) - allocno_order[i] = i; - - /* Default the size to 1, since allocno_compare uses it to divide by. - Also convert allocno_live_length of zero to -1. A length of zero - can occur when all the registers for that allocno have reg_live_length - equal to -2. In this case, we want to make an allocno, but not - allocate it. So avoid the divide-by-zero and set it to a low - priority. */ - - for (i = 0; i < max_allocno; i++) - { - if (allocno_size[i] == 0) - allocno_size[i] = 1; - if (allocno_live_length[i] == 0) - allocno_live_length[i] = -1; - } - - qsort (allocno_order, max_allocno, sizeof (int), allocno_compare); - - prune_preferences (); - - if (file) - dump_conflicts (file); - - /* Try allocating them, one by one, in that order, - except for parameters marked with reg_live_length[regno] == -2. */ - - for (i = 0; i < max_allocno; i++) - if (reg_live_length[allocno_reg[allocno_order[i]]] >= 0) - { - /* If we have more than one register class, - first try allocating in the class that is cheapest - for this pseudo-reg. If that fails, try any reg. */ - if (N_REG_CLASSES > 1) - { - find_reg (allocno_order[i], HARD_CONST (0), 0, 0, 0); - if (reg_renumber[allocno_reg[allocno_order[i]]] >= 0) - continue; - } - if (reg_alternate_class (allocno_reg[allocno_order[i]]) != NO_REGS) - find_reg (allocno_order[i], HARD_CONST (0), 1, 0, 0); - } - } - - /* Do the reloads now while the allocno data still exist, so that we can - try to assign new hard regs to any pseudo regs that are spilled. */ - -#if 0 /* We need to eliminate regs even if there is no rtl code, - for the sake of debugging information. */ - if (n_basic_blocks > 0) -#endif - return reload (get_insns (), 1, file); -} - -/* Sort predicate for ordering the allocnos. - Returns -1 (1) if *v1 should be allocated before (after) *v2. */ - -static int -allocno_compare (v1, v2) - int *v1, *v2; -{ - /* Note that the quotient will never be bigger than - the value of floor_log2 times the maximum number of - times a register can occur in one insn (surely less than 100). - Multiplying this by 10000 can't overflow. */ - register int pri1 - = (((double) (floor_log2 (allocno_n_refs[*v1]) * allocno_n_refs[*v1]) - / allocno_live_length[*v1]) - * 10000 * allocno_size[*v1]); - register int pri2 - = (((double) (floor_log2 (allocno_n_refs[*v2]) * allocno_n_refs[*v2]) - / allocno_live_length[*v2]) - * 10000 * allocno_size[*v2]); - if (pri2 - pri1) - return pri2 - pri1; - - /* If regs are equally good, sort by allocno, - so that the results of qsort leave nothing to chance. */ - return *v1 - *v2; -} - -/* Scan the rtl code and record all conflicts and register preferences in the - conflict matrices and preference tables. */ - -static void -global_conflicts () -{ - register int b, i; - register rtx insn; - short *block_start_allocnos; - - /* Make a vector that mark_reg_{store,clobber} will store in. */ - regs_set = (rtx *) alloca (max_parallel * sizeof (rtx) * 2); - - block_start_allocnos = (short *) alloca (max_allocno * sizeof (short)); - - for (b = 0; b < n_basic_blocks; b++) - { - bzero ((char *) allocnos_live, allocno_row_words * sizeof (INT_TYPE)); - - /* Initialize table of registers currently live - to the state at the beginning of this basic block. - This also marks the conflicts among them. - - For pseudo-regs, there is only one bit for each one - no matter how many hard regs it occupies. - This is ok; we know the size from PSEUDO_REGNO_SIZE. - For explicit hard regs, we cannot know the size that way - since one hard reg can be used with various sizes. - Therefore, we must require that all the hard regs - implicitly live as part of a multi-word hard reg - are explicitly marked in basic_block_live_at_start. */ - - { - register int offset; - REGSET_ELT_TYPE bit; - register regset old = basic_block_live_at_start[b]; - int ax = 0; - -#ifdef HARD_REG_SET - hard_regs_live = old[0]; -#else - COPY_HARD_REG_SET (hard_regs_live, old); -#endif - for (offset = 0, i = 0; offset < regset_size; offset++) - if (old[offset] == 0) - i += REGSET_ELT_BITS; - else - for (bit = 1; bit; bit <<= 1, i++) - { - if (i >= max_regno) - break; - if (old[offset] & bit) - { - register int a = reg_allocno[i]; - if (a >= 0) - { - SET_ALLOCNO_LIVE (a); - block_start_allocnos[ax++] = a; - } - else if ((a = reg_renumber[i]) >= 0) - mark_reg_live_nc (a, PSEUDO_REGNO_MODE (i)); - } - } - - /* Record that each allocno now live conflicts with each other - allocno now live, and with each hard reg now live. */ - - record_conflicts (block_start_allocnos, ax); - } - - insn = basic_block_head[b]; - - /* Scan the code of this basic block, noting which allocnos - and hard regs are born or die. When one is born, - record a conflict with all others currently live. */ - - while (1) - { - register RTX_CODE code = GET_CODE (insn); - register rtx link; - - /* Make regs_set an empty set. */ - - n_regs_set = 0; - - if (code == INSN || code == CALL_INSN || code == JUMP_INSN) - { - -#if 0 - int i = 0; - for (link = REG_NOTES (insn); - link && i < NUM_NO_CONFLICT_PAIRS; - link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_NO_CONFLICT) - { - no_conflict_pairs[i].allocno1 - = reg_allocno[REGNO (SET_DEST (PATTERN (insn)))]; - no_conflict_pairs[i].allocno2 - = reg_allocno[REGNO (XEXP (link, 0))]; - i++; - } -#endif /* 0 */ - - /* Mark any registers clobbered by INSN as live, - so they conflict with the inputs. */ - - note_stores (PATTERN (insn), mark_reg_clobber); - - /* Mark any registers dead after INSN as dead now. */ - - for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_DEAD) - mark_reg_death (XEXP (link, 0)); - - /* Mark any registers set in INSN as live, - and mark them as conflicting with all other live regs. - Clobbers are processed again, so they conflict with - the registers that are set. */ - - note_stores (PATTERN (insn), mark_reg_store); - -#ifdef AUTO_INC_DEC - for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_INC) - mark_reg_store (XEXP (link, 0), NULL_RTX); -#endif - - /* If INSN has multiple outputs, then any reg that dies here - and is used inside of an output - must conflict with the other outputs. */ - - if (GET_CODE (PATTERN (insn)) == PARALLEL && !single_set (insn)) - for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_DEAD) - { - int used_in_output = 0; - int i; - rtx reg = XEXP (link, 0); - - for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) - { - rtx set = XVECEXP (PATTERN (insn), 0, i); - if (GET_CODE (set) == SET - && GET_CODE (SET_DEST (set)) != REG - && !rtx_equal_p (reg, SET_DEST (set)) - && reg_overlap_mentioned_p (reg, SET_DEST (set))) - used_in_output = 1; - } - if (used_in_output) - mark_reg_conflicts (reg); - } - - /* Mark any registers set in INSN and then never used. */ - - while (n_regs_set > 0) - if (find_regno_note (insn, REG_UNUSED, - REGNO (regs_set[--n_regs_set]))) - mark_reg_death (regs_set[n_regs_set]); - } - - if (insn == basic_block_end[b]) - break; - insn = NEXT_INSN (insn); - } - } -} -/* Expand the preference information by looking for cases where one allocno - dies in an insn that sets an allocno. If those two allocnos don't conflict, - merge any preferences between those allocnos. */ - -static void -expand_preferences () -{ - rtx insn; - rtx link; - rtx set; - - /* We only try to handle the most common cases here. Most of the cases - where this wins are reg-reg copies. */ - - for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) - if (GET_RTX_CLASS (GET_CODE (insn)) == 'i' - && (set = single_set (insn)) != 0 - && GET_CODE (SET_DEST (set)) == REG - && reg_allocno[REGNO (SET_DEST (set))] >= 0) - for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) - if (REG_NOTE_KIND (link) == REG_DEAD - && GET_CODE (XEXP (link, 0)) == REG - && reg_allocno[REGNO (XEXP (link, 0))] >= 0 - && ! CONFLICTP (reg_allocno[REGNO (SET_DEST (set))], - reg_allocno[REGNO (XEXP (link, 0))]) - && ! CONFLICTP (reg_allocno[REGNO (XEXP (link, 0))], - reg_allocno[REGNO (SET_DEST (set))])) - { - int a1 = reg_allocno[REGNO (SET_DEST (set))]; - int a2 = reg_allocno[REGNO (XEXP (link, 0))]; - - if (XEXP (link, 0) == SET_SRC (set)) - { - IOR_HARD_REG_SET (hard_reg_copy_preferences[a1], - hard_reg_copy_preferences[a2]); - IOR_HARD_REG_SET (hard_reg_copy_preferences[a2], - hard_reg_copy_preferences[a1]); - } - - IOR_HARD_REG_SET (hard_reg_preferences[a1], - hard_reg_preferences[a2]); - IOR_HARD_REG_SET (hard_reg_preferences[a2], - hard_reg_preferences[a1]); - IOR_HARD_REG_SET (hard_reg_full_preferences[a1], - hard_reg_full_preferences[a2]); - IOR_HARD_REG_SET (hard_reg_full_preferences[a2], - hard_reg_full_preferences[a1]); - } -} - -/* Prune the preferences for global registers to exclude registers that cannot - be used. - - Compute `regs_someone_prefers', which is a bitmask of the hard registers - that are preferred by conflicting registers of lower priority. If possible, - we will avoid using these registers. */ - -static void -prune_preferences () -{ - int i, j; - int allocno; - - /* Scan least most important to most important. - For each allocno, remove from preferences registers that cannot be used, - either because of conflicts or register type. Then compute all registers - preferred by each lower-priority register that conflicts. */ - - for (i = max_allocno - 1; i >= 0; i--) - { - HARD_REG_SET temp; - - allocno = allocno_order[i]; - COPY_HARD_REG_SET (temp, hard_reg_conflicts[allocno]); - - if (allocno_calls_crossed[allocno] == 0) - IOR_HARD_REG_SET (temp, fixed_reg_set); - else - IOR_HARD_REG_SET (temp, call_used_reg_set); - - IOR_COMPL_HARD_REG_SET - (temp, - reg_class_contents[(int) reg_preferred_class (allocno_reg[allocno])]); - - AND_COMPL_HARD_REG_SET (hard_reg_preferences[allocno], temp); - AND_COMPL_HARD_REG_SET (hard_reg_copy_preferences[allocno], temp); - AND_COMPL_HARD_REG_SET (hard_reg_full_preferences[allocno], temp); - - CLEAR_HARD_REG_SET (regs_someone_prefers[allocno]); - - /* Merge in the preferences of lower-priority registers (they have - already been pruned). If we also prefer some of those registers, - don't exclude them unless we are of a smaller size (in which case - we want to give the lower-priority allocno the first chance for - these registers). */ - for (j = i + 1; j < max_allocno; j++) - if (CONFLICTP (allocno, allocno_order[j])) - { - COPY_HARD_REG_SET (temp, - hard_reg_full_preferences[allocno_order[j]]); - if (allocno_size[allocno_order[j]] <= allocno_size[allocno]) - AND_COMPL_HARD_REG_SET (temp, - hard_reg_full_preferences[allocno]); - - IOR_HARD_REG_SET (regs_someone_prefers[allocno], temp); - } - } -} - -/* Assign a hard register to ALLOCNO; look for one that is the beginning - of a long enough stretch of hard regs none of which conflicts with ALLOCNO. - The registers marked in PREFREGS are tried first. - - LOSERS, if non-zero, is a HARD_REG_SET indicating registers that cannot - be used for this allocation. - - If ALT_REGS_P is zero, consider only the preferred class of ALLOCNO's reg. - Otherwise ignore that preferred class and use the alternate class. - - If ACCEPT_CALL_CLOBBERED is nonzero, accept a call-clobbered hard reg that - will have to be saved and restored at calls. - - RETRYING is nonzero if this is called from retry_global_alloc. - - If we find one, record it in reg_renumber. - If not, do nothing. */ - -static void -find_reg (allocno, losers, alt_regs_p, accept_call_clobbered, retrying) - int allocno; - HARD_REG_SET losers; - int alt_regs_p; - int accept_call_clobbered; - int retrying; -{ - register int i, best_reg, pass; -#ifdef HARD_REG_SET - register /* Declare it register if it's a scalar. */ -#endif - HARD_REG_SET used, used1, used2; - - enum reg_class class = (alt_regs_p - ? reg_alternate_class (allocno_reg[allocno]) - : reg_preferred_class (allocno_reg[allocno])); - enum machine_mode mode = PSEUDO_REGNO_MODE (allocno_reg[allocno]); - - if (accept_call_clobbered) - COPY_HARD_REG_SET (used1, call_fixed_reg_set); - else if (allocno_calls_crossed[allocno] == 0) - COPY_HARD_REG_SET (used1, fixed_reg_set); - else - COPY_HARD_REG_SET (used1, call_used_reg_set); - - /* Some registers should not be allocated in global-alloc. */ - IOR_HARD_REG_SET (used1, no_global_alloc_regs); - if (losers) - IOR_HARD_REG_SET (used1, losers); - - IOR_COMPL_HARD_REG_SET (used1, reg_class_contents[(int) class]); - COPY_HARD_REG_SET (used2, used1); - - IOR_HARD_REG_SET (used1, hard_reg_conflicts[allocno]); - -#ifdef CLASS_CANNOT_CHANGE_SIZE - if (reg_changes_size[allocno_reg[allocno]]) - IOR_HARD_REG_SET (used1, - reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE]); -#endif - - /* Try each hard reg to see if it fits. Do this in two passes. - In the first pass, skip registers that are preferred by some other pseudo - to give it a better chance of getting one of those registers. Only if - we can't get a register when excluding those do we take one of them. - However, we never allocate a register for the first time in pass 0. */ - - COPY_HARD_REG_SET (used, used1); - IOR_COMPL_HARD_REG_SET (used, regs_used_so_far); - IOR_HARD_REG_SET (used, regs_someone_prefers[allocno]); - - best_reg = -1; - for (i = FIRST_PSEUDO_REGISTER, pass = 0; - pass <= 1 && i >= FIRST_PSEUDO_REGISTER; - pass++) - { - if (pass == 1) - COPY_HARD_REG_SET (used, used1); - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - { -#ifdef REG_ALLOC_ORDER - int regno = reg_alloc_order[i]; -#else - int regno = i; -#endif - if (! TEST_HARD_REG_BIT (used, regno) - && HARD_REGNO_MODE_OK (regno, mode)) - { - register int j; - register int lim = regno + HARD_REGNO_NREGS (regno, mode); - for (j = regno + 1; - (j < lim - && ! TEST_HARD_REG_BIT (used, j)); - j++); - if (j == lim) - { - best_reg = regno; - break; - } -#ifndef REG_ALLOC_ORDER - i = j; /* Skip starting points we know will lose */ -#endif - } - } - } - - /* See if there is a preferred register with the same class as the register - we allocated above. Making this restriction prevents register - preferencing from creating worse register allocation. - - Remove from the preferred registers and conflicting registers. Note that - additional conflicts may have been added after `prune_preferences' was - called. - - First do this for those register with copy preferences, then all - preferred registers. */ - - AND_COMPL_HARD_REG_SET (hard_reg_copy_preferences[allocno], used); - GO_IF_HARD_REG_SUBSET (hard_reg_copy_preferences[allocno], - reg_class_contents[(int) NO_REGS], no_copy_prefs); - - if (best_reg >= 0) - { - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (TEST_HARD_REG_BIT (hard_reg_copy_preferences[allocno], i) - && HARD_REGNO_MODE_OK (i, mode) - && (REGNO_REG_CLASS (i) == REGNO_REG_CLASS (best_reg) - || reg_class_subset_p (REGNO_REG_CLASS (i), - REGNO_REG_CLASS (best_reg)) - || reg_class_subset_p (REGNO_REG_CLASS (best_reg), - REGNO_REG_CLASS (i)))) - { - register int j; - register int lim = i + HARD_REGNO_NREGS (i, mode); - for (j = i + 1; - (j < lim - && ! TEST_HARD_REG_BIT (used, j) - && (REGNO_REG_CLASS (j) - == REGNO_REG_CLASS (best_reg + (j - i)) - || reg_class_subset_p (REGNO_REG_CLASS (j), - REGNO_REG_CLASS (best_reg + (j - i))) - || reg_class_subset_p (REGNO_REG_CLASS (best_reg + (j - i)), - REGNO_REG_CLASS (j)))); - j++); - if (j == lim) - { - best_reg = i; - goto no_prefs; - } - } - } - no_copy_prefs: - - AND_COMPL_HARD_REG_SET (hard_reg_preferences[allocno], used); - GO_IF_HARD_REG_SUBSET (hard_reg_preferences[allocno], - reg_class_contents[(int) NO_REGS], no_prefs); - - if (best_reg >= 0) - { - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (TEST_HARD_REG_BIT (hard_reg_preferences[allocno], i) - && HARD_REGNO_MODE_OK (i, mode) - && (REGNO_REG_CLASS (i) == REGNO_REG_CLASS (best_reg) - || reg_class_subset_p (REGNO_REG_CLASS (i), - REGNO_REG_CLASS (best_reg)) - || reg_class_subset_p (REGNO_REG_CLASS (best_reg), - REGNO_REG_CLASS (i)))) - { - register int j; - register int lim = i + HARD_REGNO_NREGS (i, mode); - for (j = i + 1; - (j < lim - && ! TEST_HARD_REG_BIT (used, j) - && (REGNO_REG_CLASS (j) - == REGNO_REG_CLASS (best_reg + (j - i)) - || reg_class_subset_p (REGNO_REG_CLASS (j), - REGNO_REG_CLASS (best_reg + (j - i))) - || reg_class_subset_p (REGNO_REG_CLASS (best_reg + (j - i)), - REGNO_REG_CLASS (j)))); - j++); - if (j == lim) - { - best_reg = i; - break; - } - } - } - no_prefs: - - /* If we haven't succeeded yet, try with caller-saves. - We need not check to see if the current function has nonlocal - labels because we don't put any pseudos that are live over calls in - registers in that case. */ - - if (flag_caller_saves && best_reg < 0) - { - /* Did not find a register. If it would be profitable to - allocate a call-clobbered register and save and restore it - around calls, do that. */ - if (! accept_call_clobbered - && allocno_calls_crossed[allocno] != 0 - && CALLER_SAVE_PROFITABLE (allocno_n_refs[allocno], - allocno_calls_crossed[allocno])) - { - find_reg (allocno, losers, alt_regs_p, 1, retrying); - if (reg_renumber[allocno_reg[allocno]] >= 0) - { - caller_save_needed = 1; - return; - } - } - } - - /* If we haven't succeeded yet, - see if some hard reg that conflicts with us - was utilized poorly by local-alloc. - If so, kick out the regs that were put there by local-alloc - so we can use it instead. */ - if (best_reg < 0 && !retrying - /* Let's not bother with multi-reg allocnos. */ - && allocno_size[allocno] == 1) - { - /* Count from the end, to find the least-used ones first. */ - for (i = FIRST_PSEUDO_REGISTER - 1; i >= 0; i--) - { -#ifdef REG_ALLOC_ORDER - int regno = reg_alloc_order[i]; -#else - int regno = i; -#endif - - if (local_reg_n_refs[regno] != 0 - /* Don't use a reg no good for this pseudo. */ - && ! TEST_HARD_REG_BIT (used2, regno) - && HARD_REGNO_MODE_OK (regno, mode) -#ifdef CLASS_CANNOT_CHANGE_SIZE - && ! (reg_changes_size[allocno_reg[allocno]] - && (TEST_HARD_REG_BIT - (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE], - regno))) -#endif - ) - { - /* We explicitly evaluate the divide results into temporary - variables so as to avoid excess precision problems that occur - on a i386-unknown-sysv4.2 (unixware) host. */ - - double tmp1 = ((double) local_reg_n_refs[regno] - / local_reg_live_length[regno]); - double tmp2 = ((double) allocno_n_refs[allocno] - / allocno_live_length[allocno]); - - if (tmp1 < tmp2) - { - /* Hard reg REGNO was used less in total by local regs - than it would be used by this one allocno! */ - int k; - for (k = 0; k < max_regno; k++) - if (reg_renumber[k] >= 0) - { - int r = reg_renumber[k]; - int endregno - = r + HARD_REGNO_NREGS (r, PSEUDO_REGNO_MODE (k)); - - if (regno >= r && regno < endregno) - reg_renumber[k] = -1; - } - - best_reg = regno; - break; - } - } - } - } - - /* Did we find a register? */ - - if (best_reg >= 0) - { - register int lim, j; - HARD_REG_SET this_reg; - - /* Yes. Record it as the hard register of this pseudo-reg. */ - reg_renumber[allocno_reg[allocno]] = best_reg; - /* Also of any pseudo-regs that share with it. */ - if (reg_may_share[allocno_reg[allocno]]) - for (j = FIRST_PSEUDO_REGISTER; j < max_regno; j++) - if (reg_allocno[j] == allocno) - reg_renumber[j] = best_reg; - - /* Make a set of the hard regs being allocated. */ - CLEAR_HARD_REG_SET (this_reg); - lim = best_reg + HARD_REGNO_NREGS (best_reg, mode); - for (j = best_reg; j < lim; j++) - { - SET_HARD_REG_BIT (this_reg, j); - SET_HARD_REG_BIT (regs_used_so_far, j); - /* This is no longer a reg used just by local regs. */ - local_reg_n_refs[j] = 0; - } - /* For each other pseudo-reg conflicting with this one, - mark it as conflicting with the hard regs this one occupies. */ - lim = allocno; - for (j = 0; j < max_allocno; j++) - if (CONFLICTP (lim, j) || CONFLICTP (j, lim)) - { - IOR_HARD_REG_SET (hard_reg_conflicts[j], this_reg); - } - } -} - -/* Called from `reload' to look for a hard reg to put pseudo reg REGNO in. - Perhaps it had previously seemed not worth a hard reg, - or perhaps its old hard reg has been commandeered for reloads. - FORBIDDEN_REGS indicates certain hard regs that may not be used, even if - they do not appear to be allocated. - If FORBIDDEN_REGS is zero, no regs are forbidden. */ - -void -retry_global_alloc (regno, forbidden_regs) - int regno; - HARD_REG_SET forbidden_regs; -{ - int allocno = reg_allocno[regno]; - if (allocno >= 0) - { - /* If we have more than one register class, - first try allocating in the class that is cheapest - for this pseudo-reg. If that fails, try any reg. */ - if (N_REG_CLASSES > 1) - find_reg (allocno, forbidden_regs, 0, 0, 1); - if (reg_renumber[regno] < 0 - && reg_alternate_class (regno) != NO_REGS) - find_reg (allocno, forbidden_regs, 1, 0, 1); - - /* If we found a register, modify the RTL for the register to - show the hard register, and mark that register live. */ - if (reg_renumber[regno] >= 0) - { - REGNO (regno_reg_rtx[regno]) = reg_renumber[regno]; - mark_home_live (regno); - } - } -} - -/* Record a conflict between register REGNO - and everything currently live. - REGNO must not be a pseudo reg that was allocated - by local_alloc; such numbers must be translated through - reg_renumber before calling here. */ - -static void -record_one_conflict (regno) - int regno; -{ - register int j; - - if (regno < FIRST_PSEUDO_REGISTER) - /* When a hard register becomes live, - record conflicts with live pseudo regs. */ - for (j = 0; j < max_allocno; j++) - { - if (ALLOCNO_LIVE_P (j)) - SET_HARD_REG_BIT (hard_reg_conflicts[j], regno); - } - else - /* When a pseudo-register becomes live, - record conflicts first with hard regs, - then with other pseudo regs. */ - { - register int ialloc = reg_allocno[regno]; - register int ialloc_prod = ialloc * allocno_row_words; - IOR_HARD_REG_SET (hard_reg_conflicts[ialloc], hard_regs_live); - for (j = allocno_row_words - 1; j >= 0; j--) - { -#if 0 - int k; - for (k = 0; k < n_no_conflict_pairs; k++) - if (! ((j == no_conflict_pairs[k].allocno1 - && ialloc == no_conflict_pairs[k].allocno2) - || - (j == no_conflict_pairs[k].allocno2 - && ialloc == no_conflict_pairs[k].allocno1))) -#endif /* 0 */ - conflicts[ialloc_prod + j] |= allocnos_live[j]; - } - } -} - -/* Record all allocnos currently live as conflicting - with each other and with all hard regs currently live. - ALLOCNO_VEC is a vector of LEN allocnos, all allocnos that - are currently live. Their bits are also flagged in allocnos_live. */ - -static void -record_conflicts (allocno_vec, len) - register short *allocno_vec; - register int len; -{ - register int allocno; - register int j; - register int ialloc_prod; - - while (--len >= 0) - { - allocno = allocno_vec[len]; - ialloc_prod = allocno * allocno_row_words; - IOR_HARD_REG_SET (hard_reg_conflicts[allocno], hard_regs_live); - for (j = allocno_row_words - 1; j >= 0; j--) - conflicts[ialloc_prod + j] |= allocnos_live[j]; - } -} - -/* Handle the case where REG is set by the insn being scanned, - during the forward scan to accumulate conflicts. - Store a 1 in regs_live or allocnos_live for this register, record how many - consecutive hardware registers it actually needs, - and record a conflict with all other registers already live. - - Note that even if REG does not remain alive after this insn, - we must mark it here as live, to ensure a conflict between - REG and any other regs set in this insn that really do live. - This is because those other regs could be considered after this. - - REG might actually be something other than a register; - if so, we do nothing. - - SETTER is 0 if this register was modified by an auto-increment (i.e., - a REG_INC note was found for it). - - CLOBBERs are processed here by calling mark_reg_clobber. */ - -static void -mark_reg_store (orig_reg, setter) - rtx orig_reg, setter; -{ - register int regno; - register rtx reg = orig_reg; - - /* WORD is which word of a multi-register group is being stored. - For the case where the store is actually into a SUBREG of REG. - Except we don't use it; I believe the entire REG needs to be - made live. */ - int word = 0; - - if (GET_CODE (reg) == SUBREG) - { - word = SUBREG_WORD (reg); - reg = SUBREG_REG (reg); - } - - if (GET_CODE (reg) != REG) - return; - - if (setter && GET_CODE (setter) == CLOBBER) - { - /* A clobber of a register should be processed here too. */ - mark_reg_clobber (orig_reg, setter); - return; - } - - regs_set[n_regs_set++] = reg; - - if (setter) - set_preference (reg, SET_SRC (setter)); - - regno = REGNO (reg); - - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno] /* + word */; - - /* Either this is one of the max_allocno pseudo regs not allocated, - or it is or has a hardware reg. First handle the pseudo-regs. */ - if (regno >= FIRST_PSEUDO_REGISTER) - { - if (reg_allocno[regno] >= 0) - { - SET_ALLOCNO_LIVE (reg_allocno[regno]); - record_one_conflict (regno); - } - } - /* Handle hardware regs (and pseudos allocated to hard regs). */ - else if (! fixed_regs[regno]) - { - register int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg)); - while (regno < last) - { - record_one_conflict (regno); - SET_HARD_REG_BIT (hard_regs_live, regno); - regno++; - } - } -} - -/* Like mark_reg_set except notice just CLOBBERs; ignore SETs. */ - -static void -mark_reg_clobber (reg, setter) - rtx reg, setter; -{ - register int regno; - - /* WORD is which word of a multi-register group is being stored. - For the case where the store is actually into a SUBREG of REG. - Except we don't use it; I believe the entire REG needs to be - made live. */ - int word = 0; - - if (GET_CODE (setter) != CLOBBER) - return; - - if (GET_CODE (reg) == SUBREG) - { - word = SUBREG_WORD (reg); - reg = SUBREG_REG (reg); - } - - if (GET_CODE (reg) != REG) - return; - - regs_set[n_regs_set++] = reg; - - regno = REGNO (reg); - - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno] /* + word */; - - /* Either this is one of the max_allocno pseudo regs not allocated, - or it is or has a hardware reg. First handle the pseudo-regs. */ - if (regno >= FIRST_PSEUDO_REGISTER) - { - if (reg_allocno[regno] >= 0) - { - SET_ALLOCNO_LIVE (reg_allocno[regno]); - record_one_conflict (regno); - } - } - /* Handle hardware regs (and pseudos allocated to hard regs). */ - else if (! fixed_regs[regno]) - { - register int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg)); - while (regno < last) - { - record_one_conflict (regno); - SET_HARD_REG_BIT (hard_regs_live, regno); - regno++; - } - } -} - -/* Record that REG has conflicts with all the regs currently live. - Do not mark REG itself as live. */ - -static void -mark_reg_conflicts (reg) - rtx reg; -{ - register int regno; - - if (GET_CODE (reg) == SUBREG) - reg = SUBREG_REG (reg); - - if (GET_CODE (reg) != REG) - return; - - regno = REGNO (reg); - - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno]; - - /* Either this is one of the max_allocno pseudo regs not allocated, - or it is or has a hardware reg. First handle the pseudo-regs. */ - if (regno >= FIRST_PSEUDO_REGISTER) - { - if (reg_allocno[regno] >= 0) - record_one_conflict (regno); - } - /* Handle hardware regs (and pseudos allocated to hard regs). */ - else if (! fixed_regs[regno]) - { - register int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg)); - while (regno < last) - { - record_one_conflict (regno); - regno++; - } - } -} - -/* Mark REG as being dead (following the insn being scanned now). - Store a 0 in regs_live or allocnos_live for this register. */ - -static void -mark_reg_death (reg) - rtx reg; -{ - register int regno = REGNO (reg); - - /* For pseudo reg, see if it has been assigned a hardware reg. */ - if (reg_renumber[regno] >= 0) - regno = reg_renumber[regno]; - - /* Either this is one of the max_allocno pseudo regs not allocated, - or it is a hardware reg. First handle the pseudo-regs. */ - if (regno >= FIRST_PSEUDO_REGISTER) - { - if (reg_allocno[regno] >= 0) - CLEAR_ALLOCNO_LIVE (reg_allocno[regno]); - } - /* Handle hardware regs (and pseudos allocated to hard regs). */ - else if (! fixed_regs[regno]) - { - /* Pseudo regs already assigned hardware regs are treated - almost the same as explicit hardware regs. */ - register int last = regno + HARD_REGNO_NREGS (regno, GET_MODE (reg)); - while (regno < last) - { - CLEAR_HARD_REG_BIT (hard_regs_live, regno); - regno++; - } - } -} - -/* Mark hard reg REGNO as currently live, assuming machine mode MODE - for the value stored in it. MODE determines how many consecutive - registers are actually in use. Do not record conflicts; - it is assumed that the caller will do that. */ - -static void -mark_reg_live_nc (regno, mode) - register int regno; - enum machine_mode mode; -{ - register int last = regno + HARD_REGNO_NREGS (regno, mode); - while (regno < last) - { - SET_HARD_REG_BIT (hard_regs_live, regno); - regno++; - } -} - -/* Try to set a preference for an allocno to a hard register. - We are passed DEST and SRC which are the operands of a SET. It is known - that SRC is a register. If SRC or the first operand of SRC is a register, - try to set a preference. If one of the two is a hard register and the other - is a pseudo-register, mark the preference. - - Note that we are not as aggressive as local-alloc in trying to tie a - pseudo-register to a hard register. */ - -static void -set_preference (dest, src) - rtx dest, src; -{ - int src_regno, dest_regno; - /* Amount to add to the hard regno for SRC, or subtract from that for DEST, - to compensate for subregs in SRC or DEST. */ - int offset = 0; - int i; - int copy = 1; - - if (GET_RTX_FORMAT (GET_CODE (src))[0] == 'e') - src = XEXP (src, 0), copy = 0; - - /* Get the reg number for both SRC and DEST. - If neither is a reg, give up. */ - - if (GET_CODE (src) == REG) - src_regno = REGNO (src); - else if (GET_CODE (src) == SUBREG && GET_CODE (SUBREG_REG (src)) == REG) - { - src_regno = REGNO (SUBREG_REG (src)); - offset += SUBREG_WORD (src); - } - else - return; - - if (GET_CODE (dest) == REG) - dest_regno = REGNO (dest); - else if (GET_CODE (dest) == SUBREG && GET_CODE (SUBREG_REG (dest)) == REG) - { - dest_regno = REGNO (SUBREG_REG (dest)); - offset -= SUBREG_WORD (dest); - } - else - return; - - /* Convert either or both to hard reg numbers. */ - - if (reg_renumber[src_regno] >= 0) - src_regno = reg_renumber[src_regno]; - - if (reg_renumber[dest_regno] >= 0) - dest_regno = reg_renumber[dest_regno]; - - /* Now if one is a hard reg and the other is a global pseudo - then give the other a preference. */ - - if (dest_regno < FIRST_PSEUDO_REGISTER && src_regno >= FIRST_PSEUDO_REGISTER - && reg_allocno[src_regno] >= 0) - { - dest_regno -= offset; - if (dest_regno >= 0 && dest_regno < FIRST_PSEUDO_REGISTER) - { - if (copy) - SET_REGBIT (hard_reg_copy_preferences, - reg_allocno[src_regno], dest_regno); - - SET_REGBIT (hard_reg_preferences, - reg_allocno[src_regno], dest_regno); - for (i = dest_regno; - i < dest_regno + HARD_REGNO_NREGS (dest_regno, GET_MODE (dest)); - i++) - SET_REGBIT (hard_reg_full_preferences, reg_allocno[src_regno], i); - } - } - - if (src_regno < FIRST_PSEUDO_REGISTER && dest_regno >= FIRST_PSEUDO_REGISTER - && reg_allocno[dest_regno] >= 0) - { - src_regno += offset; - if (src_regno >= 0 && src_regno < FIRST_PSEUDO_REGISTER) - { - if (copy) - SET_REGBIT (hard_reg_copy_preferences, - reg_allocno[dest_regno], src_regno); - - SET_REGBIT (hard_reg_preferences, - reg_allocno[dest_regno], src_regno); - for (i = src_regno; - i < src_regno + HARD_REGNO_NREGS (src_regno, GET_MODE (src)); - i++) - SET_REGBIT (hard_reg_full_preferences, reg_allocno[dest_regno], i); - } - } -} - -/* Indicate that hard register number FROM was eliminated and replaced with - an offset from hard register number TO. The status of hard registers live - at the start of a basic block is updated by replacing a use of FROM with - a use of TO. */ - -void -mark_elimination (from, to) - int from, to; -{ - int i; - - for (i = 0; i < n_basic_blocks; i++) - if ((basic_block_live_at_start[i][from / REGSET_ELT_BITS] - & ((REGSET_ELT_TYPE) 1 << (from % REGSET_ELT_BITS))) != 0) - { - basic_block_live_at_start[i][from / REGSET_ELT_BITS] - &= ~ ((REGSET_ELT_TYPE) 1 << (from % REGSET_ELT_BITS)); - basic_block_live_at_start[i][to / REGSET_ELT_BITS] - |= ((REGSET_ELT_TYPE) 1 << (to % REGSET_ELT_BITS)); - } -} - -/* Print debugging trace information if -greg switch is given, - showing the information on which the allocation decisions are based. */ - -static void -dump_conflicts (file) - FILE *file; -{ - register int i; - register int has_preferences; - fprintf (file, ";; %d regs to allocate:", max_allocno); - for (i = 0; i < max_allocno; i++) - { - int j; - fprintf (file, " %d", allocno_reg[allocno_order[i]]); - for (j = 0; j < max_regno; j++) - if (reg_allocno[j] == allocno_order[i] - && j != allocno_reg[allocno_order[i]]) - fprintf (file, "+%d", j); - if (allocno_size[allocno_order[i]] != 1) - fprintf (file, " (%d)", allocno_size[allocno_order[i]]); - } - fprintf (file, "\n"); - - for (i = 0; i < max_allocno; i++) - { - register int j; - fprintf (file, ";; %d conflicts:", allocno_reg[i]); - for (j = 0; j < max_allocno; j++) - if (CONFLICTP (i, j) || CONFLICTP (j, i)) - fprintf (file, " %d", allocno_reg[j]); - for (j = 0; j < FIRST_PSEUDO_REGISTER; j++) - if (TEST_HARD_REG_BIT (hard_reg_conflicts[i], j)) - fprintf (file, " %d", j); - fprintf (file, "\n"); - - has_preferences = 0; - for (j = 0; j < FIRST_PSEUDO_REGISTER; j++) - if (TEST_HARD_REG_BIT (hard_reg_preferences[i], j)) - has_preferences = 1; - - if (! has_preferences) - continue; - fprintf (file, ";; %d preferences:", allocno_reg[i]); - for (j = 0; j < FIRST_PSEUDO_REGISTER; j++) - if (TEST_HARD_REG_BIT (hard_reg_preferences[i], j)) - fprintf (file, " %d", j); - fprintf (file, "\n"); - } - fprintf (file, "\n"); -} - -void -dump_global_regs (file) - FILE *file; -{ - register int i, j; - - fprintf (file, ";; Register dispositions:\n"); - for (i = FIRST_PSEUDO_REGISTER, j = 0; i < max_regno; i++) - if (reg_renumber[i] >= 0) - { - fprintf (file, "%d in %d ", i, reg_renumber[i]); - if (++j % 6 == 0) - fprintf (file, "\n"); - } - - fprintf (file, "\n\n;; Hard regs used: "); - for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (regs_ever_live[i]) - fprintf (file, " %d", i); - fprintf (file, "\n\n"); -} |
