[PATCH] D22038: [X86] Transform zext+seteq+cmp into shr+lzcnt on btver2 architecture.

[Sanjay Patel via llvm-commits]

spatel added a comment.

Did you look at doing this in DAGCombine with a TLI hook? PPC already has this or something very close in PPCTargetLowering::LowerSETCC(), so it seems like the code could simply be lifted up from there?

Would x86 targets other than btver2 want to do this transform when optimizing for size?


http://reviews.llvm.org/D22038