[all-commits] [llvm/llvm-project] d6b68d: [X86][SSE] combineExtractWithShuffle - support zer...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d6b68d134415300cad55220bfb80e4934217ba19
      https://github.com/llvm/llvm-project/commit/d6b68d134415300cad55220bfb80e4934217ba19
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2021-01-29 (Fri, 29 Jan 2021)

  Changed paths:
    M llvm/lib/Target/X86/X86ISelLowering.cpp
    M llvm/test/CodeGen/X86/avg.ll
    M llvm/test/CodeGen/X86/buildvec-insertvec.ll
    M llvm/test/CodeGen/X86/promote-vec3.ll
    M llvm/test/CodeGen/X86/shrink_vmul.ll
    M llvm/test/CodeGen/X86/udiv_fix.ll
    M llvm/test/CodeGen/X86/udiv_fix_sat.ll
    M llvm/test/CodeGen/X86/vec-strict-inttofp-256.ll
    M llvm/test/CodeGen/X86/vector-constrained-fp-intrinsics.ll

  Log Message:
  -----------
  [X86][SSE] combineExtractWithShuffle - support zero-extending to allow extracting from narrow shuffle masks

If the shuffle mask can't be widened to match the original extracted element width, see if the upper bits are zeroable - which allows us to extract+zero-extend the smaller extraction.