diff options
Diffstat (limited to 'llvm/lib/Analysis/InstructionSimplify.cpp')
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index 61e7296d05f..aca19de4f17 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -833,14 +833,15 @@ static Value *SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF, (FMF.noSignedZeros() || CannotBeNegativeZero(Op0))) return Op0; - // fsub 0, (fsub -0.0, X) ==> X + // fsub -0.0, (fsub -0.0, X) ==> X Value *X; - if (match(Op0, m_AnyZero())) { - if (match(Op1, m_FSub(m_NegZero(), m_Value(X)))) - return X; - if (FMF.noSignedZeros() && match(Op1, m_FSub(m_AnyZero(), m_Value(X)))) - return X; - } + if (match(Op0, m_NegZero()) && match(Op1, m_FSub(m_NegZero(), m_Value(X)))) + return X; + + // fsub 0.0, (fsub 0.0, X) ==> X if signed zeros are ignored. + if (FMF.noSignedZeros() && match(Op0, m_NegZero()) && + match(Op1, m_FSub(m_AnyZero(), m_Value(X)))) + return X; // fsub nnan x, x ==> 0.0 if (FMF.noNaNs() && Op0 == Op1) |
