aboutsummaryrefslogtreecommitdiff
path: root/gcc/global.c
diff options
context:
space:
mode:
Diffstat (limited to 'gcc/global.c')
-rw-r--r--gcc/global.c98
1 files changed, 81 insertions, 17 deletions
diff --git a/gcc/global.c b/gcc/global.c
index 35fec4a4392..4e5d5a910f4 100644
--- a/gcc/global.c
+++ b/gcc/global.c
@@ -1,6 +1,6 @@
/* Allocate registers for pseudo-registers that span basic blocks.
Copyright (C) 1987, 1988, 1991, 1994, 1996, 1997, 1998,
- 1999, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
+ 1999, 2000, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of GCC.
@@ -37,6 +37,14 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
#include "output.h"
#include "toplev.h"
+/* APPLE LOCAL begin rewrite weight computation */
+/* The rewritten weight computation works fine on Darwin, but causes
+ bootstrap compares to fail on Linux. */
+#ifdef CONFIG_DARWIN_H
+#define REWRITE_WEIGHT_COMPUTATION
+#endif
+/* APPLE LOCAL end rewrite weight computation */
+
/* 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
@@ -225,6 +233,18 @@ static HARD_REG_SET regs_used_so_far;
static int local_reg_n_refs[FIRST_PSEUDO_REGISTER];
+/* APPLE LOCAL begin rewrite weight computation */
+#ifdef REWRITE_WEIGHT_COMPUTATION
+/* Overall weight of each hard reg, as used by local alloc.
+ This was formerly computed once as
+ SUM(REG_FREQ(i))/SUM(REG_LIVE_LENGTH(i)) where the sums
+ are computed over all uses. But that computation produces very
+ wrong answers when a reg is used both inside and outside a loop.
+ Now it is computed as
+ SUM (REG_FREQ(i)/REG_LIVE_LENGTH(i)) over all uses. */
+
+static double local_reg_weight[FIRST_PSEUDO_REGISTER];
+#else
/* Frequency of uses of given hard reg. */
static int local_reg_freq[FIRST_PSEUDO_REGISTER];
@@ -232,6 +252,8 @@ static int local_reg_freq[FIRST_PSEUDO_REGISTER];
This is actually the sum of the live lengths of the specific regs. */
static int local_reg_live_length[FIRST_PSEUDO_REGISTER];
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+/* APPLE LOCAL end rewrite weight computation */
/* Set to 1 a bit in a vector TABLE of HARD_REG_SETs, for vector
element I, and hard register number J. */
@@ -493,9 +515,17 @@ global_alloc (FILE *file)
/* Calculate amount of usage of each hard reg by pseudos
allocated by local-alloc. This is to see if we want to
override it. */
+ /* APPLE LOCAL begin rewrite weight computation */
+#ifndef REWRITE_WEIGHT_COMPUTATION
memset (local_reg_live_length, 0, sizeof local_reg_live_length);
+#endif /* REWRITE_WEIGHT_COMPUTATION */
memset (local_reg_n_refs, 0, sizeof local_reg_n_refs);
+#ifdef REWRITE_WEIGHT_COMPUTATION
+ memset (local_reg_weight, 0, sizeof local_reg_weight);
+#else
memset (local_reg_freq, 0, sizeof local_reg_freq);
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+ /* APPLE LOCAL end rewrite weight computation */
for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
if (reg_renumber[i] >= 0)
{
@@ -506,15 +536,29 @@ global_alloc (FILE *file)
for (j = regno; j < endregno; j++)
{
local_reg_n_refs[j] += REG_N_REFS (i);
+ /* APPLE LOCAL begin rewrite weight computation */
+#ifdef REWRITE_WEIGHT_COMPUTATION
+ if ( REG_LIVE_LENGTH (i) > 0 )
+ local_reg_weight[j] += (double)REG_FREQ (i)
+ / (double) REG_LIVE_LENGTH (i);
+#else
local_reg_freq[j] += REG_FREQ (i);
local_reg_live_length[j] += REG_LIVE_LENGTH (i);
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+ /* APPLE LOCAL end rewrite weight computation */
}
}
/* 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])
+ /* APPLE LOCAL begin rewrite weight computation */
+#ifdef REWRITE_WEIGHT_COMPUTATION
+ local_reg_n_refs[i] = 0;
+#else
local_reg_n_refs[i] = 0, local_reg_freq[i] = 0;
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+ /* APPLE LOCAL end rewrite weight computation */
allocno_row_words = (max_allocno + INT_BITS - 1) / INT_BITS;
@@ -1265,6 +1309,15 @@ find_reg (int num, HARD_REG_SET losers, int alt_regs_p, int accept_call_clobbere
#endif
)
{
+ /* APPLE LOCAL begin rewrite weight computation */
+#ifdef REWRITE_WEIGHT_COMPUTATION
+ /* We explicitly evaluate the divide result into a temporary
+ variable so as to avoid excess precision problems that occur
+ on an i386-unknown-sysv4.2 (unixware) host. */
+ double tmp = ((double) allocno[num].freq
+ / allocno[num].live_length);
+#else
+ /* APPLE LOCAL end rewrite weight computation */
/* We explicitly evaluate the divide results into temporary
variables so as to avoid excess precision problems that occur
on an i386-unknown-sysv4.2 (unixware) host. */
@@ -1273,8 +1326,15 @@ find_reg (int num, HARD_REG_SET losers, int alt_regs_p, int accept_call_clobbere
/ local_reg_live_length[regno]);
double tmp2 = ((double) allocno[num].freq
/ allocno[num].live_length);
+ /* APPLE LOCAL begin rewrite weight computation */
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+#ifdef REWRITE_WEIGHT_COMPUTATION
+ if (local_reg_weight[regno] < tmp)
+#else
if (tmp1 < tmp2)
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+ /* APPLE LOCAL end rewrite weight computation */
{
/* Hard reg REGNO was used less in total by local regs
than it would be used by this one allocno! */
@@ -1321,7 +1381,11 @@ find_reg (int num, HARD_REG_SET losers, int alt_regs_p, int accept_call_clobbere
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;
+ /* APPLE LOCAL begin rewrite weight computation */
+#ifndef REWRITE_WEIGHT_COMPUTATION
local_reg_freq[j] = 0;
+#endif /* REWRITE_WEIGHT_COMPUTATION */
+ /* APPLE LOCAL end rewrite weight computation */
}
/* For each other pseudo-reg conflicting with this one,
mark it as conflicting with the hard regs this one occupies. */
@@ -2033,21 +2097,21 @@ allocate_bb_info (void)
bitmap init;
alloc_aux_for_blocks (sizeof (struct bb_info));
- init = BITMAP_XMALLOC ();
+ init = BITMAP_ALLOC (NULL);
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
bitmap_set_bit (init, i);
FOR_EACH_BB (bb)
{
bb_info = bb->aux;
- bb_info->earlyclobber = BITMAP_XMALLOC ();
- bb_info->avloc = BITMAP_XMALLOC ();
- bb_info->killed = BITMAP_XMALLOC ();
- bb_info->live_pavin = BITMAP_XMALLOC ();
- bb_info->live_pavout = BITMAP_XMALLOC ();
+ bb_info->earlyclobber = BITMAP_ALLOC (NULL);
+ bb_info->avloc = BITMAP_ALLOC (NULL);
+ bb_info->killed = BITMAP_ALLOC (NULL);
+ bb_info->live_pavin = BITMAP_ALLOC (NULL);
+ bb_info->live_pavout = BITMAP_ALLOC (NULL);
bitmap_copy (bb_info->live_pavin, init);
bitmap_copy (bb_info->live_pavout, init);
}
- BITMAP_XFREE (init);
+ BITMAP_FREE (init);
}
/* The function frees the allocated info of all basic blocks. */
@@ -2061,11 +2125,11 @@ free_bb_info (void)
FOR_EACH_BB (bb)
{
bb_info = BB_INFO (bb);
- BITMAP_XFREE (bb_info->live_pavout);
- BITMAP_XFREE (bb_info->live_pavin);
- BITMAP_XFREE (bb_info->killed);
- BITMAP_XFREE (bb_info->avloc);
- BITMAP_XFREE (bb_info->earlyclobber);
+ BITMAP_FREE (bb_info->live_pavout);
+ BITMAP_FREE (bb_info->live_pavin);
+ BITMAP_FREE (bb_info->killed);
+ BITMAP_FREE (bb_info->avloc);
+ BITMAP_FREE (bb_info->earlyclobber);
}
free_aux_for_blocks ();
}
@@ -2297,7 +2361,7 @@ calculate_reg_pav (void)
VARRAY_BB_INIT (bbs, n_basic_blocks, "basic blocks");
VARRAY_BB_INIT (new_bbs, n_basic_blocks, "basic blocks for the next iter.");
- temp_bitmap = BITMAP_XMALLOC ();
+ temp_bitmap = BITMAP_ALLOC (NULL);
FOR_EACH_BB (bb)
{
VARRAY_PUSH_BB (bbs, bb);
@@ -2351,7 +2415,7 @@ calculate_reg_pav (void)
VARRAY_POP_ALL (new_bbs);
}
sbitmap_free (wset);
- BITMAP_XFREE (temp_bitmap);
+ BITMAP_FREE (temp_bitmap);
}
/* The function modifies partial availability information for two
@@ -2373,7 +2437,7 @@ modify_reg_pav (void)
CLEAR_HARD_REG_SET (stack_hard_regs);
for (i = FIRST_STACK_REG; i <= LAST_STACK_REG; i++)
SET_HARD_REG_BIT(stack_hard_regs, i);
- stack_regs = BITMAP_XMALLOC ();
+ stack_regs = BITMAP_ALLOC (NULL);
for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
{
COPY_HARD_REG_SET (used, reg_class_contents[reg_preferred_class (i)]);
@@ -2405,7 +2469,7 @@ modify_reg_pav (void)
#endif
}
#ifdef STACK_REGS
- BITMAP_XFREE (stack_regs);
+ BITMAP_FREE (stack_regs);
#endif
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-08 17:03:11 +0000