From: Dale Johannesen Date: Thu, 16 May 2002 21:30:48 +0000 (+0000) Subject: Reenable combination of hard regs unless CLASS_LIKELY_SPILLED_P. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=63b827c591e3ef7e44d8bc2de25356bb220c9d47;p=gcc.git Reenable combination of hard regs unless CLASS_LIKELY_SPILLED_P. From-SVN: r53531 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a9b68cfe3ee..43b6a8c6d6e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2002-05-16 Dale Johannesen + + * combine.c (cant_combine_insn_p): Reenable combinations + involving hard regs unless CLASS_LIKELY_SPILLED_P. + 2002-05-16 Neil Booth * c-common.c (cb_register_builtins): Handle more built-ins diff --git a/gcc/combine.c b/gcc/combine.c index 10587fda84e..aaf1bcf3e26 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -1459,10 +1459,10 @@ cant_combine_insn_p (insn) if (! INSN_P (insn)) return 1; - /* Never combine loads and stores involving hard regs. The register - allocator can usually handle such reg-reg moves by tying. If we allow - the combiner to make substitutions of hard regs, we risk aborting in - reload on machines that have SMALL_REGISTER_CLASSES. + /* Never combine loads and stores involving hard regs that are likely + to be spilled. The register allocator can usually handle such + reg-reg moves by tying. If we allow the combiner to make + substitutions of likely-spilled regs, we may abort in reload. As an exception, we allow combinations involving fixed regs; these are not available to the register allocator so there's no risk involved. */ @@ -1477,9 +1477,11 @@ cant_combine_insn_p (insn) dest = SUBREG_REG (dest); if (REG_P (src) && REG_P (dest) && ((REGNO (src) < FIRST_PSEUDO_REGISTER - && ! fixed_regs[REGNO (src)]) + && ! fixed_regs[REGNO (src)] + && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (src)))) || (REGNO (dest) < FIRST_PSEUDO_REGISTER - && ! fixed_regs[REGNO (dest)]))) + && ! fixed_regs[REGNO (dest)] + && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (dest)))))) return 1; return 0;