[all-commits] [llvm/llvm-project] 5b395b: [CostModel][X86] Add costs for multiply-by-pow2 co...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5b395bd633632b9f87f4d853095cb1a090a1efe6
      https://github.com/llvm/llvm-project/commit/5b395bd633632b9f87f4d853095cb1a090a1efe6
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2021-10-20 (Wed, 20 Oct 2021)

  Changed paths:
    M llvm/lib/Target/X86/X86TargetTransformInfo.cpp
    M llvm/test/Analysis/CostModel/X86/mul.ll

  Log Message:
  -----------
  [CostModel][X86] Add costs for multiply-by-pow2 constants

These are folded to left shifts in the backend.

We should be able to extend this for multiply-by-negpow2 after D111968 has landed to resolve PR51436