[all-commits] [llvm/llvm-project] 45299f: Reapply [AArch64] fold subs ugt/ult to ands when t...

[chenglin.bi via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 45299fb0f99cd94aeb33d954c4d68123a0bc7e9e
      https://github.com/llvm/llvm-project/commit/45299fb0f99cd94aeb33d954c4d68123a0bc7e9e
  Author: chenglin.bi <chenglin.bi at linaro.org>
  Date:   2023-01-18 (Wed, 18 Jan 2023)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/test/CodeGen/AArch64/and-mask-removal.ll
    M llvm/test/CodeGen/AArch64/andcompare.ll

  Log Message:
  -----------
  Reapply [AArch64] fold subs ugt/ult to ands when the second operand is mask/pow2

Origianl patch made a mistake that ugt is reverse cc should be ule.
And ule < C will be generalize to ult < C + 1. So the new patch add support for ult < Pow2 case.

https://alive2.llvm.org/ce/z/naBw5A

Reviewed By: samtebbs, chapuni

Differential Revision: https://reviews.llvm.org/D141829