[all-commits] [llvm/llvm-project] 807b01: [ConstantFolding] Fixing addo/subo with undef

[George Mitenkov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 807b019ca292e53cc40cc76c1f0efd8a7b2efe62
      https://github.com/llvm/llvm-project/commit/807b019ca292e53cc40cc76c1f0efd8a7b2efe62
  Author: George Mitenkov <georgemitenk0v at gmail.com>
  Date:   2021-03-31 (Wed, 31 Mar 2021)

  Changed paths:
    M llvm/lib/Analysis/ConstantFolding.cpp
    M llvm/test/Transforms/InstSimplify/ConstProp/overflow-ops.ll

  Log Message:
  -----------
  [ConstantFolding] Fixing addo/subo with undef

When folding addo/subo with undef, the current
convention is to use { -1, false } for addo and
{ 0, false } for subo. This was fixed for InstSimplify in
https://reviews.llvm.org/rGf094d65beaa492e845b03561eddd75b5be653a01,
but not in ConstantFolding.

Reviewed By: nikic, lebedev.ri

Differential Revision: https://reviews.llvm.org/D99564