diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineAddSub.cpp')
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineAddSub.cpp | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp index 03be8ef6fb..c6d60d6f00 100644 --- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -1250,6 +1250,16 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { if (SimplifyDemandedInstructionBits(I)) return &I; + + // Fold (sub 0, (zext bool to B)) --> (sext bool to B) + if (C->isZero() && match(Op1, m_ZExt(m_Value(X)))) + if (X->getType()->isIntegerTy(1)) + return CastInst::CreateSExtOrBitCast(X, Op1->getType()); + + // Fold (sub 0, (sext bool to B)) --> (zext bool to B) + if (C->isZero() && match(Op1, m_SExt(m_Value(X)))) + if (X->getType()->isIntegerTy(1)) + return CastInst::CreateZExtOrBitCast(X, Op1->getType()); } |