[all-commits] [llvm/llvm-project] f81200: [InstCombine] add one-use check to add+xor transform

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  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: f81200ae9959e0b0c66a2191f30afb8dd5bf7afa
      https://github.com/llvm/llvm-project/commit/f81200ae9959e0b0c66a2191f30afb8dd5bf7afa
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2020-10-11 (Sun, 11 Oct 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
    M llvm/test/Transforms/InstCombine/signext.ll

  Log Message:
  -----------
  [InstCombine] add one-use check to add+xor transform

As shown in the affected test, we could increase instruction
count without this limitation. There's another test with extra
use that shows we still convert directly to a real "sext" if
possible.