Commit Graph

2 Commits

Author SHA1 Message Date
NAKAMURA Takumi 576273cf56 test/CodeGen/X86/shrink-compare.ll: Relax expressions for Win64.
llvm-svn: 130039
2011-04-23 00:15:45 +00:00
Benjamin Kramer 341c11da3b DAGCombine: fold "(zext x) == C" into "x == (trunc C)" if the trunc is lossless.
On x86 this allows to fold a load into the cmp, greatly reducing register pressure.
  movzbl	(%rdi), %eax
  cmpl	$47, %eax
->
  cmpb	$47, (%rdi)

This shaves 8k off gcc.o on i386. I'll leave applying the patch in README.txt to Chris :)

llvm-svn: 130005
2011-04-22 18:47:44 +00:00