[PATCH] D141653: [X86] Improve instruction ordering of constant `srl/shl` with `and` to get better and-masks

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


================
Comment at: llvm/test/CodeGen/X86/bitreverse.ll:538
-; X64-NEXT:    andb $8, %al
-; X64-NEXT:    leal (%rdi,%rdi), %ecx
-; X64-NEXT:    andb $4, %cl
----------------
pengfei wrote:
> IIRC, LEA is expensive, so this looks like a good deal. 
I thought LEA was only expensive if it uses 3 sources.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D141653/new/

https://reviews.llvm.org/D141653