/* Allocate registers for pseudo-registers that span basic blocks.
Copyright (C) 1987, 1988, 1991, 1994, 1996, 1997, 1998,
- 1999, 2000, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007
+ 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
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "reload.h"
#include "output.h"
#include "toplev.h"
+#include "tree-pass.h"
+#include "timevar.h"
+#include "df.h"
+#include "vecprim.h"
+#include "dbgcnt.h"
/* This pass of the compiler performs global register allocation.
It assigns hard register numbers to all the pseudo registers
/* Number of calls crossed by each allocno. */
int calls_crossed;
+ /* Number of calls that might throw crossed by each allocno. */
+ int throwing_calls_crossed;
+
/* Number of refs to each allocno. */
int n_refs;
static int *allocno_order;
-/* 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. */
static INT_TYPE *conflicts;
-/* Number of ints require to hold max_allocno bits.
+/* Number of ints required to hold max_allocno bits.
This is the length of a row in `conflicts'. */
static int allocno_row_words;
} \
} while (0)
-/* This doesn't work for non-GNU C due to the way CODE is macro expanded. */
-#if 0
-/* For any allocno that conflicts with IN_ALLOCNO, set OUT_ALLOCNO to
- the conflicting allocno, and execute CODE. This macro assumes that
- mirror_conflicts has been run. */
-#define EXECUTE_IF_CONFLICT(IN_ALLOCNO, OUT_ALLOCNO, CODE)\
- EXECUTE_IF_SET_IN_ALLOCNO_SET (conflicts + (IN_ALLOCNO) * allocno_row_words,\
- OUT_ALLOCNO, (CODE))
-#endif
-
/* Set of hard regs currently live (during scan of all insns). */
static HARD_REG_SET hard_regs_live;
/* 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;
+static VEC(rtx, heap) *regs_set;
+
+
+/* Return true if *LOC contains an asm. */
+
+static int
+insn_contains_asm_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
+{
+ if ( !*loc)
+ return 0;
+ if (GET_CODE (*loc) == ASM_OPERANDS)
+ return 1;
+ return 0;
+}
+
+
+/* Return true if INSN contains an ASM. */
+
+static int
+insn_contains_asm (rtx insn)
+{
+ return for_each_rtx (&insn, insn_contains_asm_1, NULL);
+}
+
+
+static void
+compute_regs_asm_clobbered (char *regs_asm_clobbered)
+{
+ basic_block bb;
+
+ memset (regs_asm_clobbered, 0, sizeof (char) * FIRST_PSEUDO_REGISTER);
+
+ FOR_EACH_BB (bb)
+ {
+ rtx insn;
+ FOR_BB_INSNS_REVERSE (bb, insn)
+ {
+ struct df_ref **def_rec;
+ if (insn_contains_asm (insn))
+ for (def_rec = DF_INSN_DEFS (insn); *def_rec; def_rec++)
+ {
+ struct df_ref *def = *def_rec;
+ unsigned int dregno = DF_REF_REGNO (def);
+ if (dregno < FIRST_PSEUDO_REGISTER)
+ {
+ unsigned int i;
+ enum machine_mode mode = GET_MODE (DF_REF_REAL_REG (def));
+ unsigned int end = dregno
+ + hard_regno_nregs[dregno][mode] - 1;
+ for (i = dregno; i <= end; ++i)
+ regs_asm_clobbered[i] = 1;
+ }
+ }
+ }
+ }
+}
+
/* All registers that can be eliminated. */
static void find_reg (int, HARD_REG_SET, int, int, int);
static void record_one_conflict (int);
static void record_conflicts (int *, int);
-static void mark_reg_store (rtx, rtx, void *);
-static void mark_reg_clobber (rtx, rtx, void *);
+static void mark_reg_store (rtx, const_rtx, void *);
+static void mark_reg_clobber (rtx, const_rtx, void *);
static void mark_reg_conflicts (rtx);
static void mark_reg_death (rtx);
-static void mark_reg_live_nc (int, enum machine_mode);
static void set_preference (rtx, rtx);
static void dump_conflicts (FILE *);
-static void reg_becomes_live (rtx, rtx, void *);
+static void reg_becomes_live (rtx, const_rtx, void *);
static void reg_dies (int, enum machine_mode, struct insn_chain *);
-static void allocate_bb_info (void);
-static void free_bb_info (void);
-static bool check_earlyclobber (rtx);
-static void mark_reg_use_for_earlyclobber_1 (rtx *, void *);
-static int mark_reg_use_for_earlyclobber (rtx *, void *);
-static void calculate_local_reg_bb_info (void);
-static void set_up_bb_rts_numbers (void);
-static int rpost_cmp (const void *, const void *);
-static void calculate_reg_pav (void);
-static void modify_reg_pav (void);
-static void make_accurate_live_analysis (void);
\f
-/* 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.
+/* Look through the list of eliminable registers. Set ELIM_SET to the
+ set of registers which may be eliminated. Set NO_GLOBAL_SET to the
+ set of registers which may not be used across blocks.
- Return value is nonzero if reload failed
- and we must not do any more for this function. */
+ This will normally be called with ELIM_SET as the file static
+ variable eliminable_regset, and NO_GLOBAL_SET as the file static
+ variable NO_GLOBAL_ALLOC_REGS. */
-int
-global_alloc (FILE *file)
+static void
+compute_regsets (HARD_REG_SET *elim_set,
+ HARD_REG_SET *no_global_set)
{
- int retval;
+
+/* Like regs_ever_live, but 1 if a reg is set or clobbered from an asm.
+ Unlike regs_ever_live, elements of this array corresponding to
+ eliminable regs like the frame pointer are set if an asm sets them. */
+ char *regs_asm_clobbered = alloca (FIRST_PSEUDO_REGISTER * sizeof (char));
+
#ifdef ELIMINABLE_REGS
static const struct {const int from, to; } eliminables[] = ELIMINABLE_REGS;
+ size_t i;
#endif
int need_fp
= (! flag_omit_frame_pointer
|| (current_function_calls_alloca && EXIT_IGNORE_STACK)
|| FRAME_POINTER_REQUIRED);
- size_t i;
- rtx x;
-
- make_accurate_live_analysis ();
+ max_regno = max_reg_num ();
+ compact_blocks ();
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);
+ CLEAR_HARD_REG_SET (*no_global_set);
+ CLEAR_HARD_REG_SET (*elim_set);
+ compute_regs_asm_clobbered (regs_asm_clobbered);
/* 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
if (!regs_asm_clobbered[eliminables[i].from])
{
- SET_HARD_REG_BIT (eliminable_regset, eliminables[i].from);
+ SET_HARD_REG_BIT (*elim_set, eliminables[i].from);
if (cannot_elim)
- SET_HARD_REG_BIT (no_global_alloc_regs, eliminables[i].from);
+ SET_HARD_REG_BIT (*no_global_set, eliminables[i].from);
}
else if (cannot_elim)
error ("%s cannot be used in asm here",
reg_names[eliminables[i].from]);
else
- regs_ever_live[eliminables[i].from] = 1;
+ df_set_regs_ever_live (eliminables[i].from, true);
}
#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
if (!regs_asm_clobbered[HARD_FRAME_POINTER_REGNUM])
{
- SET_HARD_REG_BIT (eliminable_regset, HARD_FRAME_POINTER_REGNUM);
+ SET_HARD_REG_BIT (*elim_set, HARD_FRAME_POINTER_REGNUM);
if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, HARD_FRAME_POINTER_REGNUM);
+ SET_HARD_REG_BIT (*no_global_set, HARD_FRAME_POINTER_REGNUM);
}
else if (need_fp)
error ("%s cannot be used in asm here",
reg_names[HARD_FRAME_POINTER_REGNUM]);
else
- regs_ever_live[HARD_FRAME_POINTER_REGNUM] = 1;
+ df_set_regs_ever_live (HARD_FRAME_POINTER_REGNUM, true);
#endif
#else
if (!regs_asm_clobbered[FRAME_POINTER_REGNUM])
{
- SET_HARD_REG_BIT (eliminable_regset, FRAME_POINTER_REGNUM);
+ SET_HARD_REG_BIT (*elim_set, FRAME_POINTER_REGNUM);
if (need_fp)
- SET_HARD_REG_BIT (no_global_alloc_regs, FRAME_POINTER_REGNUM);
+ SET_HARD_REG_BIT (*no_global_set, FRAME_POINTER_REGNUM);
}
else if (need_fp)
error ("%s cannot be used in asm here", reg_names[FRAME_POINTER_REGNUM]);
else
- regs_ever_live[FRAME_POINTER_REGNUM] = 1;
+ df_set_regs_ever_live (FRAME_POINTER_REGNUM, true);
#endif
+}
+
+/* Perform allocation of pseudo-registers not allocated by local_alloc.
+
+ Return value is nonzero if reload failed
+ and we must not do any more for this function. */
+
+static int
+global_alloc (void)
+{
+ int retval;
+ size_t i;
+
+ compute_regsets (&eliminable_regset, &no_global_alloc_regs);
/* Track which registers have already been used. Start with registers
explicitly in the rtl, then registers allocated by local register
else
cheap_regs = call_used_regs;
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i] || cheap_regs[i])
+ if (df_regs_ever_live_p (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])
+ if (df_regs_ever_live_p (i) || call_used_regs[i])
SET_HARD_REG_BIT (regs_used_so_far, i);
#endif
/* Establish mappings from register number to allocation number
and vice versa. In the process, count the allocnos. */
- reg_allocno = xmalloc (max_regno * sizeof (int));
+ reg_allocno = XNEWVEC (int, max_regno);
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 = xcalloc (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;
- }
-
+ max_allocno = 0;
for (i = FIRST_PSEUDO_REGISTER; i < (size_t) 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.
&& (! current_function_has_nonlocal_label
|| REG_N_CALLS_CROSSED (i) == 0))
{
- if (reg_renumber[i] < 0
- && 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++;
+ reg_allocno[i] = max_allocno++;
gcc_assert (REG_LIVE_LENGTH (i));
}
else
reg_allocno[i] = -1;
- allocno = xcalloc (max_allocno, sizeof (struct allocno));
+ allocno = XCNEWVEC (struct allocno, max_allocno);
for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
if (reg_allocno[i] >= 0)
allocno[num].reg = i;
allocno[num].size = PSEUDO_REGNO_SIZE (i);
allocno[num].calls_crossed += REG_N_CALLS_CROSSED (i);
+ allocno[num].throwing_calls_crossed
+ += REG_N_THROWING_CALLS_CROSSED (i);
allocno[num].n_refs += REG_N_REFS (i);
allocno[num].freq += REG_FREQ (i);
if (allocno[num].live_length < REG_LIVE_LENGTH (i))
if (reg_renumber[i] >= 0)
{
int regno = reg_renumber[i];
- int endregno = regno + hard_regno_nregs[regno][PSEUDO_REGNO_MODE (i)];
+ int endregno = end_hard_regno (PSEUDO_REGNO_MODE (i), regno);
int j;
for (j = regno; j < endregno; j++)
/* 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])
+ if (df_regs_ever_live_p (i))
local_reg_n_refs[i] = 0, local_reg_freq[i] = 0;
+ if (dump_file)
+ {
+ for (i = FIRST_PSEUDO_REGISTER; i < (size_t) max_regno; i++)
+ {
+ fprintf (dump_file, "%d REG_N_REFS=%d, REG_FREQ=%d, REG_LIVE_LENGTH=%d\n",
+ (int)i, REG_N_REFS (i), REG_FREQ (i), REG_LIVE_LENGTH (i));
+ }
+ fprintf (dump_file, "regs_ever_live =");
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (df_regs_ever_live_p (i))
+ fprintf (dump_file, " %d", (int)i);
+ fprintf (dump_file, "\n");
+ }
allocno_row_words = (max_allocno + INT_BITS - 1) / INT_BITS;
/* We used to use alloca here, but the size of what it would try to
allocate would occasionally cause it to exceed the stack limit and
cause unpredictable core dumps. Some examples were > 2Mb in size. */
- conflicts = xcalloc (max_allocno * allocno_row_words, sizeof (INT_TYPE));
+ conflicts = XCNEWVEC (INT_TYPE, max_allocno * allocno_row_words);
- allocnos_live = xmalloc (allocno_row_words * sizeof (INT_TYPE));
+ allocnos_live = XNEWVEC (INT_TYPE, allocno_row_words);
/* 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)
{
+ /* Make a vector that mark_reg_{store,clobber} will store in. */
+ if (!regs_set)
+ regs_set = VEC_alloc (rtx, heap, 10);
+
/* Scan all the insns and compute the conflicts among allocnos
and between allocnos and hard regs. */
/* Determine the order to allocate the remaining pseudo registers. */
- allocno_order = xmalloc (max_allocno * sizeof (int));
+ allocno_order = XNEWVEC (int, max_allocno);
for (i = 0; i < (size_t) max_allocno; i++)
allocno_order[i] = i;
prune_preferences ();
- if (file)
- dump_conflicts (file);
+ if (dump_file)
+ dump_conflicts (dump_file);
/* Try allocating them, one by one, in that order,
except for parameters marked with reg_live_length[regno] == -2. */
if (reg_renumber[allocno[allocno_order[i]].reg] < 0
&& REG_LIVE_LENGTH (allocno[allocno_order[i]].reg) >= 0)
{
+ if (!dbg_cnt (global_alloc_at_reg))
+ break;
/* 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. */
free (allocno_order);
}
- /* Do the reloads now while the allocno data still exist, so that we can
+ /* Do the reloads now while the allocno data still exists, 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)
+ if (n_basic_blocks > NUM_FIXED_BLOCKS)
#endif
{
build_insn_chain (get_insns ());
/* Clean up. */
free (reg_allocno);
- free (reg_may_share);
free (allocno);
free (conflicts);
free (allocnos_live);
rtx insn;
int *block_start_allocnos;
- /* Make a vector that mark_reg_{store,clobber} will store in. */
- regs_set = xmalloc (max_parallel * sizeof (rtx) * 2);
-
- block_start_allocnos = xmalloc (max_allocno * sizeof (int));
+ block_start_allocnos = XNEWVEC (int, max_allocno);
FOR_EACH_BB (b)
{
be explicitly marked in basic_block_live_at_start. */
{
- regset old = b->global_live_at_start;
int ax = 0;
reg_set_iterator rsi;
- REG_SET_TO_HARD_REG_SET (hard_regs_live, old);
- EXECUTE_IF_SET_IN_REG_SET (old, FIRST_PSEUDO_REGISTER, i, rsi)
+ REG_SET_TO_HARD_REG_SET (hard_regs_live, DF_RA_LIVE_TOP (b));
+ EXECUTE_IF_SET_IN_REG_SET (DF_RA_LIVE_TOP (b), FIRST_PSEUDO_REGISTER, i, rsi)
{
int a = reg_allocno[i];
if (a >= 0)
block_start_allocnos[ax++] = a;
}
else if ((a = reg_renumber[i]) >= 0)
- mark_reg_live_nc (a, PSEUDO_REGNO_MODE (i));
+ add_to_hard_reg_set (&hard_regs_live, PSEUDO_REGNO_MODE (i), a);
}
/* Record that each allocno now live conflicts with each hard reg
now live.
- It is not necessary to mark any conflicts between pseudos as
+ It is not necessary to mark any conflicts between pseudos at
this point, even for pseudos which are live at the start of
the basic block.
scan the instruction that makes either X or Y become live. */
record_conflicts (block_start_allocnos, ax);
+#ifdef EH_RETURN_DATA_REGNO
+ if (bb_has_eh_pred (b))
+ {
+ unsigned int i;
+
+ for (i = 0; ; ++i)
+ {
+ unsigned int regno = EH_RETURN_DATA_REGNO (i);
+ if (regno == INVALID_REGNUM)
+ break;
+ record_one_conflict (regno);
+ }
+ }
+#endif
+
/* Pseudos can't go in stack regs at the start of a basic block that
is reached by an abnormal edge. Likewise for call clobbered regs,
- because because caller-save, fixup_abnormal_edges, and possibly
- the table driven EH machinery are not quite ready to handle such
- regs live across such edges. */
+ because caller-save, fixup_abnormal_edges and possibly the table
+ driven EH machinery are not quite ready to handle such regs live
+ across such edges. */
{
edge e;
edge_iterator ei;
RTX_CODE code = GET_CODE (insn);
rtx link;
- /* Make regs_set an empty set. */
-
- n_regs_set = 0;
-
+ gcc_assert (VEC_empty (rtx, regs_set));
if (code == INSN || code == CALL_INSN || code == JUMP_INSN)
{
-
#if 0
int i = 0;
for (link = REG_NOTES (insn);
note_stores (PATTERN (insn), mark_reg_clobber, NULL);
+#ifdef AUTO_INC_DEC
+ /* Auto-increment instructions clobber the base
+ register. */
+ 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, NULL);
+#endif
/* Mark any registers dead after INSN as dead now. */
for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
note_stores (PATTERN (insn), mark_reg_store, NULL);
-#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, NULL);
-#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.
/* Mark any registers set in INSN and then never used. */
- while (n_regs_set-- > 0)
+ while (!VEC_empty (rtx, regs_set))
{
+ rtx reg = VEC_pop (rtx, regs_set);
rtx note = find_regno_note (insn, REG_UNUSED,
- REGNO (regs_set[n_regs_set]));
+ REGNO (reg));
if (note)
mark_reg_death (XEXP (note, 0));
}
/* Clean up. */
free (block_start_allocnos);
- free (regs_set);
}
+
/* 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. */
{
int i;
int num;
- int *allocno_to_order = xmalloc (max_allocno * sizeof (int));
+ int *allocno_to_order = XNEWVEC (int, max_allocno);
/* Scan least most important to most important.
For each allocno, remove from preferences registers that cannot be used,
|| ! HARD_REGNO_CALL_PART_CLOBBERED (regno, mode)))
{
int j;
- int lim = regno + hard_regno_nregs[regno][mode];
+ int lim = end_hard_regno (mode, regno);
for (j = regno + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j));
preferred registers. */
AND_COMPL_HARD_REG_SET (allocno[num].hard_reg_copy_preferences, used);
- GO_IF_HARD_REG_SUBSET (allocno[num].hard_reg_copy_preferences,
- reg_class_contents[(int) NO_REGS], no_copy_prefs);
-
- if (best_reg >= 0)
+ if (!hard_reg_set_empty_p (allocno[num].hard_reg_copy_preferences)
+ && best_reg >= 0)
{
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (TEST_HARD_REG_BIT (allocno[num].hard_reg_copy_preferences, i)
REGNO_REG_CLASS (i))))
{
int j;
- int lim = i + hard_regno_nregs[i][mode];
+ int lim = end_hard_regno (mode, i);
for (j = i + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j)
}
}
}
- no_copy_prefs:
AND_COMPL_HARD_REG_SET (allocno[num].hard_reg_preferences, used);
- GO_IF_HARD_REG_SUBSET (allocno[num].hard_reg_preferences,
- reg_class_contents[(int) NO_REGS], no_prefs);
-
- if (best_reg >= 0)
+ if (!hard_reg_set_empty_p (allocno[num].hard_reg_preferences)
+ && best_reg >= 0)
{
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (TEST_HARD_REG_BIT (allocno[num].hard_reg_preferences, i)
REGNO_REG_CLASS (i))))
{
int j;
- int lim = i + hard_regno_nregs[i][mode];
+ int lim = end_hard_regno (mode, i);
for (j = i + 1;
(j < lim
&& ! TEST_HARD_REG_BIT (used, j)
{
/* 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. */
+ around calls, do that. Don't do this if it crosses any calls
+ that might throw. */
if (! accept_call_clobbered
&& allocno[num].calls_crossed != 0
+ && allocno[num].throwing_calls_crossed == 0
&& CALLER_SAVE_PROFITABLE (allocno[num].n_refs,
allocno[num].calls_crossed))
{
so we can use it instead. */
if (best_reg < 0 && !retrying
/* Let's not bother with multi-reg allocnos. */
- && allocno[num].size == 1)
+ && allocno[num].size == 1
+ && REG_BASIC_BLOCK (allocno[num].reg) == REG_BLOCK_GLOBAL)
{
/* Count from the end, to find the least-used ones first. */
for (i = FIRST_PSEUDO_REGISTER - 1; i >= 0; i--)
variables so as to avoid excess precision problems that occur
on an i386-unknown-sysv4.2 (unixware) host. */
- double tmp1 = ((double) local_reg_freq[regno]
+ double tmp1 = ((double) local_reg_freq[regno] * local_reg_n_refs[regno]
/ local_reg_live_length[regno]);
- double tmp2 = ((double) allocno[num].freq
+ double tmp2 = ((double) allocno[num].freq * allocno[num].n_refs
/ allocno[num].live_length);
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;
+ if (dump_file)
+ {
+ fprintf (dump_file, "Regno %d better for global %d, ",
+ regno, allocno[num].reg);
+ fprintf (dump_file, "fr:%d, ll:%d, nr:%d ",
+ allocno[num].freq, allocno[num].live_length,
+ allocno[num].n_refs);
+ fprintf (dump_file, "(was: fr:%d, ll:%d, nr:%d)\n",
+ local_reg_freq[regno],
+ local_reg_live_length[regno],
+ local_reg_n_refs[regno]);
+ }
+
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)];
+ = end_hard_regno (PSEUDO_REGNO_MODE (k), r);
if (regno >= r && regno < endregno)
- reg_renumber[k] = -1;
+ {
+ if (dump_file)
+ fprintf (dump_file,
+ "Local Reg %d now on stack\n", k);
+ reg_renumber[k] = -1;
+ }
}
best_reg = regno;
/* Yes. Record it as the hard register of this pseudo-reg. */
reg_renumber[allocno[num].reg] = best_reg;
- /* Also of any pseudo-regs that share with it. */
- if (reg_may_share[allocno[num].reg])
- for (j = FIRST_PSEUDO_REGISTER; j < max_regno; j++)
- if (reg_allocno[j] == num)
- 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];
+ lim = end_hard_regno (mode, best_reg);
for (j = best_reg; j < lim; j++)
{
SET_HARD_REG_BIT (this_reg, j);
show the hard register, and mark that register live. */
if (reg_renumber[regno] >= 0)
{
- REGNO (regno_reg_rtx[regno]) = reg_renumber[regno];
+ SET_REGNO (regno_reg_rtx[regno], reg_renumber[regno]);
mark_home_live (regno);
}
}
a REG_INC note was found for it). */
static void
-mark_reg_store (rtx reg, rtx setter, void *data ATTRIBUTE_UNUSED)
+mark_reg_store (rtx reg, const_rtx setter, void *data ATTRIBUTE_UNUSED)
{
int regno;
if (!REG_P (reg))
return;
- regs_set[n_regs_set++] = reg;
+ VEC_safe_push (rtx, heap, regs_set, reg);
if (setter && GET_CODE (setter) != CLOBBER)
set_preference (reg, SET_SRC (setter));
/* Handle hardware regs (and pseudos allocated to hard regs). */
if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
{
- int last = regno + hard_regno_nregs[regno][GET_MODE (reg)];
+ int last = end_hard_regno (GET_MODE (reg), regno);
while (regno < last)
{
record_one_conflict (regno);
}
}
\f
-/* Like mark_reg_set except notice just CLOBBERs; ignore SETs. */
+/* Like mark_reg_store except notice just CLOBBERs; ignore SETs. */
static void
-mark_reg_clobber (rtx reg, rtx setter, void *data)
+mark_reg_clobber (rtx reg, const_rtx setter, void *data)
{
if (GET_CODE (setter) == CLOBBER)
mark_reg_store (reg, setter, data);
/* Handle hardware regs (and pseudos allocated to hard regs). */
if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
{
- int last = regno + hard_regno_nregs[regno][GET_MODE (reg)];
+ int last = end_hard_regno (GET_MODE (reg), regno);
while (regno < last)
{
record_one_conflict (regno);
/* Handle hardware regs (and pseudos allocated to hard regs). */
if (regno < FIRST_PSEUDO_REGISTER && ! fixed_regs[regno])
- {
- /* Pseudo regs already assigned hardware regs are treated
- almost the same as explicit hardware regs. */
- 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 (int regno, enum machine_mode mode)
-{
- int last = regno + hard_regno_nregs[regno][mode];
- while (regno < last)
- {
- SET_HARD_REG_BIT (hard_regs_live, regno);
- regno++;
- }
+ /* Pseudo regs already assigned hardware regs are treated
+ almost the same as explicit hardware regs. */
+ remove_from_hard_reg_set (&hard_regs_live, GET_MODE (reg), regno);
}
\f
/* Try to set a preference for an allocno to a hard register.
static void
set_preference (rtx dest, rtx src)
{
- unsigned int src_regno, dest_regno;
+ unsigned int src_regno, dest_regno, end_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;
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++)
+ end_regno = end_hard_regno (GET_MODE (dest), dest_regno);
+ for (i = dest_regno; i < end_regno; i++)
SET_REGBIT (hard_reg_full_preferences, reg_allocno[src_regno], i);
}
}
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++)
+ end_regno = end_hard_regno (GET_MODE (src), src_regno);
+ for (i = src_regno; i < end_regno; i++)
SET_REGBIT (hard_reg_full_preferences, reg_allocno[dest_regno], i);
}
}
FOR_EACH_BB (bb)
{
- regset r = bb->global_live_at_start;
+ regset r = DF_RA_LIVE_IN (bb);
if (REGNO_REG_SET_P (r, from))
{
CLEAR_REGNO_REG_SET (r, from);
/* Record in live_relevant_regs and REGS_SET that register REG became live.
This is called via note_stores. */
static void
-reg_becomes_live (rtx reg, rtx setter ATTRIBUTE_UNUSED, void *regs_set)
+reg_becomes_live (rtx reg, const_rtx setter ATTRIBUTE_UNUSED, void *regs_set)
{
int regno;
int nregs = hard_regno_nregs[regno][GET_MODE (reg)];
while (nregs-- > 0)
{
- SET_REGNO_REG_SET (live_relevant_regs, regno);
- if (! fixed_regs[regno])
+ if (GET_CODE (setter) == CLOBBER)
+ CLEAR_REGNO_REG_SET (live_relevant_regs, regno);
+ else
+ SET_REGNO_REG_SET (live_relevant_regs, regno);
+
+ if (!fixed_regs[regno])
SET_REGNO_REG_SET ((regset) regs_set, regno);
regno++;
}
}
else if (reg_renumber[regno] >= 0)
{
- SET_REGNO_REG_SET (live_relevant_regs, regno);
+ if (GET_CODE (setter) == CLOBBER)
+ CLEAR_REGNO_REG_SET (live_relevant_regs, regno);
+ else
+ SET_REGNO_REG_SET (live_relevant_regs, regno);
SET_REGNO_REG_SET ((regset) regs_set, regno);
}
}
CLEAR_REG_SET (live_relevant_regs);
- EXECUTE_IF_SET_IN_BITMAP (b->global_live_at_start, 0, i, bi)
+ EXECUTE_IF_SET_IN_BITMAP (df_get_live_top (b), 0, i, bi)
{
if (i < FIRST_PSEUDO_REGISTER
? ! TEST_HARD_REG_BIT (eliminable_regset, i)
fprintf (file, "\n\n;; Hard regs used: ");
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (regs_ever_live[i])
+ if (df_regs_ever_live_p (i))
fprintf (file, " %d", i);
fprintf (file, "\n\n");
}
-\f
-
-/* This page contains code to make live information more accurate.
- The accurate register liveness at program point P means:
- o there is a path from P to usage of the register and the
- register is not redefined or killed on the path.
- o register at P is partially available, i.e. there is a path from
- a register definition to the point P and the register is not
- killed (clobbered) on the path
-
- The standard GCC live information means only the first condition.
- Without the partial availability, there will be more register
- conflicts and as a consequence worse register allocation. The
- typical example where the information can be different is a
- register initialized in the loop at the basic block preceding the
- loop in CFG. */
-
-/* The following structure contains basic block data flow information
- used to calculate partial availability of registers. */
-
-struct bb_info
+/* Run old register allocator. Return TRUE if we must exit
+ rest_of_compilation upon return. */
+static unsigned int
+rest_of_handle_global_alloc (void)
{
- /* The basic block reverse post-order number. */
- int rts_number;
- /* Registers used uninitialized in an insn in which there is an
- early clobbered register might get the same hard register. */
- bitmap earlyclobber;
- /* Registers correspondingly killed (clobbered) and defined but not
- killed afterward in the basic block. */
- bitmap killed, avloc;
- /* Registers partially available and living (in other words whose
- values were calculated and used) correspondingly at the start
- and end of the basic block. */
- bitmap live_pavin, live_pavout;
-};
-
-/* Macros for accessing data flow information of basic blocks. */
+ bool failure;
-#define BB_INFO(BB) ((struct bb_info *) (BB)->aux)
-#define BB_INFO_BY_INDEX(N) BB_INFO (BASIC_BLOCK(N))
-
-/* The function allocates the info structures of each basic block. It
- also initialized LIVE_PAVIN and LIVE_PAVOUT as if all hard
- registers were partially available. */
-
-static void
-allocate_bb_info (void)
-{
- int i;
- basic_block bb;
- struct bb_info *bb_info;
- bitmap init;
-
- alloc_aux_for_blocks (sizeof (struct bb_info));
- 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_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_FREE (init);
-}
-
-/* The function frees the allocated info of all basic blocks. */
-
-static void
-free_bb_info (void)
-{
- basic_block bb;
- struct bb_info *bb_info;
-
- FOR_EACH_BB (bb)
- {
- bb_info = BB_INFO (bb);
- 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 ();
-}
-
-/* The function modifies local info for register REG being changed in
- SETTER. DATA is used to pass the current basic block info. */
-
-static void
-mark_reg_change (rtx reg, rtx setter, void *data)
-{
- int regno;
- basic_block bb = data;
- struct bb_info *bb_info = BB_INFO (bb);
-
- if (GET_CODE (reg) == SUBREG)
- reg = SUBREG_REG (reg);
-
- if (!REG_P (reg))
- return;
-
- regno = REGNO (reg);
- bitmap_set_bit (bb_info->killed, regno);
-
- if (GET_CODE (setter) != CLOBBER)
- bitmap_set_bit (bb_info->avloc, regno);
+ /* If optimizing, allocate remaining pseudo-regs. Do the reload
+ pass fixing up any insns that are invalid. */
+ if (optimize && dbg_cnt (global_alloc_at_func))
+ failure = global_alloc ();
else
- bitmap_clear_bit (bb_info->avloc, regno);
-}
-
-/* Classes of registers which could be early clobbered in the current
- insn. */
-
-static varray_type earlyclobber_regclass;
-
-/* This function finds and stores register classes that could be early
- clobbered in INSN. If any earlyclobber classes are found, the function
- returns TRUE, in all other cases it returns FALSE. */
-
-static bool
-check_earlyclobber (rtx insn)
-{
- int opno;
- bool found = false;
-
- extract_insn (insn);
-
- VARRAY_POP_ALL (earlyclobber_regclass);
- for (opno = 0; opno < recog_data.n_operands; opno++)
- {
- char c;
- bool amp_p;
- int i;
- enum reg_class class;
- const char *p = recog_data.constraints[opno];
-
- class = NO_REGS;
- amp_p = false;
- for (;;)
- {
- c = *p;
- switch (c)
- {
- case '=': case '+': case '?':
- case '#': case '!':
- case '*': case '%':
- case 'm': case '<': case '>': case 'V': case 'o':
- case 'E': case 'F': case 'G': case 'H':
- case 's': case 'i': case 'n':
- case 'I': case 'J': case 'K': case 'L':
- case 'M': case 'N': case 'O': case 'P':
- case 'X':
- case '0': case '1': case '2': case '3': case '4':
- case '5': case '6': case '7': case '8': case '9':
- /* These don't say anything we care about. */
- break;
-
- case '&':
- amp_p = true;
- break;
- case '\0':
- case ',':
- if (amp_p && class != NO_REGS)
- {
- found = true;
- for (i = VARRAY_ACTIVE_SIZE (earlyclobber_regclass) - 1;
- i >= 0; i--)
- if (VARRAY_INT (earlyclobber_regclass, i) == (int) class)
- break;
- if (i < 0)
- VARRAY_PUSH_INT (earlyclobber_regclass, (int) class);
- }
-
- amp_p = false;
- class = NO_REGS;
- break;
-
- case 'r':
- class = GENERAL_REGS;
- break;
-
- default:
- class = REG_CLASS_FROM_CONSTRAINT (c, p);
- break;
- }
- if (c == '\0')
- break;
- p += CONSTRAINT_LEN (c, p);
- }
- }
-
- return found;
-}
-
-/* The function checks that pseudo-register *X has a class
- intersecting with the class of pseudo-register could be early
- clobbered in the same insn.
- This function is a no-op if earlyclobber_regclass is empty. */
-
-static int
-mark_reg_use_for_earlyclobber (rtx *x, void *data ATTRIBUTE_UNUSED)
-{
- enum reg_class pref_class, alt_class;
- int i, regno;
- basic_block bb = data;
- struct bb_info *bb_info = BB_INFO (bb);
-
- if (REG_P (*x) && REGNO (*x) >= FIRST_PSEUDO_REGISTER)
- {
- regno = REGNO (*x);
- if (bitmap_bit_p (bb_info->killed, regno)
- || bitmap_bit_p (bb_info->avloc, regno))
- return 0;
- pref_class = reg_preferred_class (regno);
- alt_class = reg_alternate_class (regno);
- for (i = VARRAY_ACTIVE_SIZE (earlyclobber_regclass) - 1; i >= 0; i--)
- if (reg_classes_intersect_p (VARRAY_INT (earlyclobber_regclass, i),
- pref_class)
- || (VARRAY_INT (earlyclobber_regclass, i) != NO_REGS
- && reg_classes_intersect_p (VARRAY_INT (earlyclobber_regclass,
- i),
- alt_class)))
- {
- bitmap_set_bit (bb_info->earlyclobber, regno);
- break;
- }
- }
- return 0;
-}
-
-/* The function processes all pseudo-registers in *X with the aid of
- previous function. */
-
-static void
-mark_reg_use_for_earlyclobber_1 (rtx *x, void *data)
-{
- for_each_rtx (x, mark_reg_use_for_earlyclobber, data);
-}
-
-/* The function calculates local info for each basic block. */
-
-static void
-calculate_local_reg_bb_info (void)
-{
- basic_block bb;
- rtx insn, bound;
-
- VARRAY_INT_INIT (earlyclobber_regclass, 20,
- "classes of registers early clobbered in an insn");
- FOR_EACH_BB (bb)
{
- bound = NEXT_INSN (BB_END (bb));
- for (insn = BB_HEAD (bb); insn != bound; insn = NEXT_INSN (insn))
- if (INSN_P (insn))
- {
- note_stores (PATTERN (insn), mark_reg_change, bb);
- if (check_earlyclobber (insn))
- note_uses (&PATTERN (insn), mark_reg_use_for_earlyclobber_1, bb);
- }
+ compute_regsets (&eliminable_regset, &no_global_alloc_regs);
+ build_insn_chain (get_insns ());
+ df_set_flags (DF_NO_INSN_RESCAN);
+ failure = reload (get_insns (), 0);
}
-}
-
-/* The function sets up reverse post-order number of each basic
- block. */
-
-static void
-set_up_bb_rts_numbers (void)
-{
- int i;
- int *rts_order;
-
- rts_order = xmalloc (sizeof (int) * n_basic_blocks);
- flow_reverse_top_sort_order_compute (rts_order);
- for (i = 0; i < n_basic_blocks; i++)
- BB_INFO_BY_INDEX (rts_order [i])->rts_number = i;
- free (rts_order);
-}
-
-/* Compare function for sorting blocks in reverse postorder. */
-
-static int
-rpost_cmp (const void *bb1, const void *bb2)
-{
- basic_block b1 = *(basic_block *) bb1, b2 = *(basic_block *) bb2;
-
- return BB_INFO (b2)->rts_number - BB_INFO (b1)->rts_number;
-}
-
-/* Temporary bitmap used for live_pavin, live_pavout calculation. */
-static bitmap temp_bitmap;
-/* The function calculates partial register availability according to
- the following equations:
-
- bb.live_pavin
- = empty for entry block
- | union (live_pavout of predecessors) & global_live_at_start
- bb.live_pavout = union (bb.live_pavin - bb.killed, bb.avloc)
- & global_live_at_end */
-
-static void
-calculate_reg_pav (void)
-{
- basic_block bb, succ;
- edge e;
- int i, nel;
- varray_type bbs, new_bbs, temp;
- basic_block *bb_array;
- sbitmap wset;
-
- 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_ALLOC (NULL);
- FOR_EACH_BB (bb)
+ if (dump_enabled_p (pass_global_alloc.static_pass_number))
{
- VARRAY_PUSH_BB (bbs, bb);
+ timevar_push (TV_DUMP);
+ dump_global_regs (dump_file);
+ timevar_pop (TV_DUMP);
}
- wset = sbitmap_alloc (n_basic_blocks + 1);
- while (VARRAY_ACTIVE_SIZE (bbs))
- {
- bb_array = &VARRAY_BB (bbs, 0);
- nel = VARRAY_ACTIVE_SIZE (bbs);
- qsort (bb_array, nel, sizeof (basic_block), rpost_cmp);
- sbitmap_zero (wset);
- for (i = 0; i < nel; i++)
- {
- edge_iterator ei;
- struct bb_info *bb_info;
- bitmap bb_live_pavin, bb_live_pavout;
-
- bb = bb_array [i];
- bb_info = BB_INFO (bb);
- bb_live_pavin = bb_info->live_pavin;
- bb_live_pavout = bb_info->live_pavout;
- FOR_EACH_EDGE (e, ei, bb->preds)
- {
- basic_block pred = e->src;
- if (pred->index != ENTRY_BLOCK)
- bitmap_ior_into (bb_live_pavin, BB_INFO (pred)->live_pavout);
- }
- bitmap_and_into (bb_live_pavin, bb->global_live_at_start);
- bitmap_ior_and_compl (temp_bitmap, bb_info->avloc,
- bb_live_pavin, bb_info->killed);
- bitmap_and_into (temp_bitmap, bb->global_live_at_end);
- if (! bitmap_equal_p (temp_bitmap, bb_live_pavout))
- {
- bitmap_copy (bb_live_pavout, temp_bitmap);
- FOR_EACH_EDGE (e, ei, bb->succs)
- {
- succ = e->dest;
- if (succ->index != EXIT_BLOCK
- && !TEST_BIT (wset, succ->index))
- {
- SET_BIT (wset, succ->index);
- VARRAY_PUSH_BB (new_bbs, succ);
- }
- }
- }
- }
- temp = bbs;
- bbs = new_bbs;
- new_bbs = temp;
- VARRAY_POP_ALL (new_bbs);
- }
- sbitmap_free (wset);
- BITMAP_FREE (temp_bitmap);
-}
-
-/* The function modifies partial availability information for two
- special cases to prevent incorrect work of the subsequent passes
- with the accurate live information based on the partial
- availability. */
-
-static void
-modify_reg_pav (void)
-{
- basic_block bb;
- struct bb_info *bb_info;
-#ifdef STACK_REGS
- int i;
- HARD_REG_SET zero, stack_hard_regs, used;
- bitmap stack_regs;
-
- CLEAR_HARD_REG_SET (zero);
- 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_ALLOC (NULL);
- for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
- {
- COPY_HARD_REG_SET (used, reg_class_contents[reg_preferred_class (i)]);
- IOR_HARD_REG_SET (used, reg_class_contents[reg_alternate_class (i)]);
- AND_HARD_REG_SET (used, stack_hard_regs);
- GO_IF_HARD_REG_EQUAL(used, zero, skip);
- bitmap_set_bit (stack_regs, i);
- skip:
- ;
- }
-#endif
- FOR_EACH_BB (bb)
- {
- bb_info = BB_INFO (bb);
-
- /* Reload can assign the same hard register to uninitialized
- pseudo-register and early clobbered pseudo-register in an
- insn if the pseudo-register is used first time in given BB
- and not lived at the BB start. To prevent this we don't
- change life information for such pseudo-registers. */
- bitmap_ior_into (bb_info->live_pavin, bb_info->earlyclobber);
-#ifdef STACK_REGS
- /* We can not use the same stack register for uninitialized
- pseudo-register and another living pseudo-register because if the
- uninitialized pseudo-register dies, subsequent pass reg-stack
- will be confused (it will believe that the other register
- dies). */
- bitmap_ior_into (bb_info->live_pavin, stack_regs);
-#endif
- }
-#ifdef STACK_REGS
- BITMAP_FREE (stack_regs);
-#endif
+ /* FIXME: This appears on the surface to be wrong thing to be doing.
+ So much of the compiler is designed to check reload_completed to
+ see if it is running after reload that seems doomed to failure.
+ We should be returning a value that says that we have found
+ errors so that nothing but the cleanup passes are run
+ afterwards. */
+ gcc_assert (reload_completed || failure);
+ reload_completed = !failure;
+
+ /* The world has changed so much that at this point we might as well
+ just rescan everything. Not that df_rescan_all_insns is not
+ going to help here because it does not touch the artificial uses
+ and defs. */
+ df_finish_pass (true);
+ if (optimize > 1)
+ df_live_add_problem ();
+ df_scan_alloc (NULL);
+ df_scan_blocks ();
+
+ if (optimize)
+ df_analyze ();
+
+ regstat_free_n_sets_and_refs ();
+ regstat_free_ri ();
+ return 0;
}
-/* The following function makes live information more accurate by
- modifying global_live_at_start and global_live_at_end of basic
- blocks.
-
- The standard GCC life analysis permits registers to live
- uninitialized, for example:
-
- R is never used
- .....
- Loop:
- R is defined
- ...
- R is used.
-
- With normal life_analysis, R would be live before "Loop:".
- The result is that R causes many interferences that do not
- serve any purpose.
-
- After the function call a register lives at a program point
- only if it is initialized on a path from CFG entry to the
- program point. */
-
-static void
-make_accurate_live_analysis (void)
+struct tree_opt_pass pass_global_alloc =
{
- basic_block bb;
- struct bb_info *bb_info;
+ "greg", /* name */
+ NULL, /* gate */
+ rest_of_handle_global_alloc, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_GLOBAL_ALLOC, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func |
+ TODO_ggc_collect, /* todo_flags_finish */
+ 'g' /* letter */
+};
- max_regno = max_reg_num ();
- compact_blocks ();
- allocate_bb_info ();
- calculate_local_reg_bb_info ();
- set_up_bb_rts_numbers ();
- calculate_reg_pav ();
- modify_reg_pav ();
- FOR_EACH_BB (bb)
- {
- bb_info = BB_INFO (bb);
-
- bitmap_and_into (bb->global_live_at_start, bb_info->live_pavin);
- bitmap_and_into (bb->global_live_at_end, bb_info->live_pavout);
- }
- free_bb_info ();
-}
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