[all-commits] [llvm/llvm-project] 776903: Recommit "[PatternMatch] Match XOR variant of unsi...

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 7769030b9310c1865fd331edb78dc242a39b109a
      https://github.com/llvm/llvm-project/commit/7769030b9310c1865fd331edb78dc242a39b109a
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2020-02-23 (Sun, 23 Feb 2020)

  Changed paths:
    M llvm/include/llvm/IR/PatternMatch.h
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    M llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
    M llvm/test/CodeGen/AArch64/sat-add.ll
    M llvm/test/CodeGen/X86/sat-add.ll
    M llvm/test/Transforms/CodeGenPrepare/AArch64/overflow-intrinsics.ll
    M llvm/test/Transforms/CodeGenPrepare/X86/overflow-intrinsics.ll

  Log Message:
  -----------
  Recommit "[PatternMatch] Match XOR variant of unsigned-add overflow check."

This version fixes a buildbot failure cause by picking the wrong insert
point for XORs. We cannot pick the XOR binary operator as insert point,
as it is not guaranteed that both input operands for the overflow
intrinsic are defined before it.

This reverts the revert commit
c7fc0e5da6c3c36eb5f3a874a6cdeaedb26856e0.