[all-commits] [llvm/llvm-project] 37dce7: [AArch64] Identify SAD pattern

[Vinay Madhusudan via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 37dce7475b2b97f27f65a80524a8ad8342e6cf7e
      https://github.com/llvm/llvm-project/commit/37dce7475b2b97f27f65a80524a8ad8342e6cf7e
  Author: Vinay Madhusudan <vinay at compilertree.com>
  Date:   2020-10-13 (Tue, 13 Oct 2020)

  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-vabs.ll

  Log Message:
  -----------
  [AArch64] Identify SAD pattern

(ABS (SUB (EXTEND a), (EXTEND b))) to ZERO_EXTEND((UABD a, b))
(ABS (SUB (SIGN_EXTEND a), (SIGN_EXTEND b))) to ZERO_EXTEND((SABD a, b))

This partially solves the bug: https://bugs.llvm.org/show_bug.cgi?id=46888
Meta ticket: https://bugs.llvm.org/show_bug.cgi?id=46929

Differential Revision: https://reviews.llvm.org/D88742