[all-commits] [llvm/llvm-project] 7e4420: [X86][SSE] combineSubToSubus - add v16i32 handling...

[Simon Pilgrim via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 7e44208115b35ad34cc10259e9c375abbd636ef5
      https://github.com/llvm/llvm-project/commit/7e44208115b35ad34cc10259e9c375abbd636ef5
  Author: Simon Pilgrim <llvm-dev at redking.me.uk>
  Date:   2021-01-12 (Tue, 12 Jan 2021)

  Changed paths:
    M llvm/lib/Target/X86/X86ISelLowering.cpp
    M llvm/test/CodeGen/X86/psubus.ll

  Log Message:
  -----------
  [X86][SSE] combineSubToSubus - add v16i32 handling on pre-AVX512BW targets.

v16i32 -> v16i16/v8i16 truncation is now good enough using PACKSS/PACKUS + shuffle combining that its no longer necessary to early-out on pre-AVX512BW targets.

This was noticed while looking at completing PR40111 and moving combineSubToSubus to DAGCombine entirely.