[all-commits] [llvm/llvm-project] 3acbd3: [AArch64] Optimise MOVI + CMGT to CMGE (#74499)

[Sjoerd Meijer via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3acbd38492c394dec32ccde3f11885e5b59d5aa9
      https://github.com/llvm/llvm-project/commit/3acbd38492c394dec32ccde3f11885e5b59d5aa9
  Author: Sjoerd Meijer <smeijer at nvidia.com>
  Date:   2023-12-07 (Thu, 07 Dec 2023)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/test/CodeGen/AArch64/cmp-select-sign.ll
    M llvm/test/CodeGen/AArch64/dag-numsignbits.ll
    M llvm/test/CodeGen/AArch64/signbit-shift.ll
    M llvm/test/CodeGen/AArch64/vselect-ext.ll

  Log Message:
  -----------
  [AArch64] Optimise MOVI + CMGT to CMGE (#74499)

This fixes a regression that occured for a pattern of MOVI + CMGT
instructions, which can be optimised to CMGE. I.e., when the signed
greater than compare has -1 as an operand, we can rewrite that as a
compare greater equal than 0, which is what CMGE does.

Fixes #61836