[all-commits] [llvm/llvm-project] 4ea1b4: [AArch64] Generate ADDP from shuffled add

[David Green via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 4ea1b43527c9a845942dbbc27e022d74d72728e6
      https://github.com/llvm/llvm-project/commit/4ea1b43527c9a845942dbbc27e022d74d72728e6
  Author: David Green <david.green at arm.com>
  Date:   2022-06-06 (Mon, 06 Jun 2022)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/lib/Target/AArch64/AArch64ISelLowering.h
    M llvm/lib/Target/AArch64/AArch64InstrInfo.td
    M llvm/test/CodeGen/AArch64/arm64-addp.ll
    M llvm/test/CodeGen/AArch64/insert-extend.ll
    M llvm/test/CodeGen/AArch64/reduce-shuffle.ll

  Log Message:
  -----------
  [AArch64] Generate ADDP from shuffled add

This adds a fold of add(x, shuffle(x, <1,0,3,2,5,4,...>), into
shuffle(addp(x), <0,0,1,1,2,2,..>. The ADDP instruction takes two
vectors and returns one, adding adjacent pairs. So we match x in a
custom combine as it is lowered from a v8i32. The original code
would be 2 rev64 and 2 add, with the new code being a single addp
with a zip1;zip2 shuffle, producing smaller code.

Differential Revision: https://reviews.llvm.org/D126686