[all-commits] [llvm/llvm-project] c1a36b: [DAGCombine][X86][ARM] EXTRACT_SUBVECTOR(VECTOR_SH...

[Roman Lebedev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: c1a36ba002b85c59b1f760db10c06ecab11f2c94
      https://github.com/llvm/llvm-project/commit/c1a36ba002b85c59b1f760db10c06ecab11f2c94
  Author: Roman Lebedev <lebedev.ri at gmail.com>
  Date:   2021-12-13 (Mon, 13 Dec 2021)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    M llvm/test/CodeGen/ARM/vext.ll
    M llvm/test/CodeGen/X86/vector-fshl-rot-256.ll
    M llvm/test/CodeGen/X86/vector-fshr-rot-256.ll
    M llvm/test/CodeGen/X86/vector-fshr-rot-512.ll
    M llvm/test/CodeGen/X86/vector-rotate-256.ll
    M llvm/test/CodeGen/X86/vector-shift-ashr-256.ll
    M llvm/test/CodeGen/X86/vector-shift-lshr-256.ll
    M llvm/test/CodeGen/X86/vector-shift-shl-256.ll
    M llvm/test/CodeGen/X86/vector-trunc.ll

  Log Message:
  -----------
  [DAGCombine][X86][ARM] EXTRACT_SUBVECTOR(VECTOR_SHUFFLE(?,?,Mask)) -> VECTOR_SHUFFLE(EXTRACT_SUBVECTOR(?, ?), EXTRACT_SUBVECTOR(?, ?), Mask')

In most test changes this allows us to drop some broadcasts/shuffles.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D104156