diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 1e01c87cede..582db1ffe0d 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -790,6 +790,7 @@ do_SUBST_MODE (rtx *into, enum machine_mode newval) #define SUBST_MODE(INTO, NEWVAL) do_SUBST_MODE(&(INTO), (NEWVAL)) +#ifndef HAVE_cc0 /* Similar to SUBST, but NEWVAL is a LOG_LINKS expression. */ static void @@ -815,7 +816,7 @@ do_SUBST_LINK (struct insn_link **into, struct insn_link *newval) } #define SUBST_LINK(oldval, newval) do_SUBST_LINK (&oldval, newval) - +#endif /* Subroutine of try_combine. Determine whether the replacement patterns NEWPAT, NEWI2PAT and NEWOTHERPAT are cheaper according to insn_rtx_cost @@ -1699,6 +1700,7 @@ can_combine_p (rtx insn, rtx i3, rtx pred ATTRIBUTE_UNUSED, rtx link; #endif bool all_adjacent = true; + int (*is_volatile_p) (const_rtx); if (succ) { @@ -1947,11 +1949,17 @@ can_combine_p (rtx insn, rtx i3, rtx pred ATTRIBUTE_UNUSED, && REG_P (dest) && REGNO (dest) < FIRST_PSEUDO_REGISTER) return 0; - /* If there are any volatile insns between INSN and I3, reject, because - they might affect machine state. */ + /* If INSN contains volatile references (specifically volatile MEMs), + we cannot combine across any other volatile references. + Even if INSN doesn't contain volatile references, any intervening + volatile insn might affect machine state. */ + is_volatile_p = volatile_refs_p (PATTERN (insn)) + ? volatile_refs_p + : volatile_insn_p; + for (p = NEXT_INSN (insn); p != i3; p = NEXT_INSN (p)) - if (INSN_P (p) && p != succ && p != succ2 && volatile_insn_p (PATTERN (p))) + if (INSN_P (p) && p != succ && p != succ2 && is_volatile_p (PATTERN (p))) return 0; /* If INSN contains an autoincrement or autodecrement, make sure that |