diff options
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 2 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstSimplify/fast-math.ll | 10 |
2 files changed, 11 insertions, 1 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index aca19de4f17..bb0a275f947 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -839,7 +839,7 @@ static Value *SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF, return X; // fsub 0.0, (fsub 0.0, X) ==> X if signed zeros are ignored. - if (FMF.noSignedZeros() && match(Op0, m_NegZero()) && + if (FMF.noSignedZeros() && match(Op0, m_AnyZero()) && match(Op1, m_FSub(m_AnyZero(), m_Value(X)))) return X; diff --git a/llvm/test/Transforms/InstSimplify/fast-math.ll b/llvm/test/Transforms/InstSimplify/fast-math.ll index 90532fa5db8..c499af33f52 100644 --- a/llvm/test/Transforms/InstSimplify/fast-math.ll +++ b/llvm/test/Transforms/InstSimplify/fast-math.ll @@ -91,6 +91,16 @@ define float @fsub_x_x(float %a) { ret float %ret } +; fsub nsz 0.0, (fsub 0.0, X) ==> X +; CHECK-LABEL: @fsub_0_0_x( +define float @fsub_0_0_x(float %a) { + %t1 = fsub float 0.0, %a + %ret = fsub nsz float 0.0, %t1 + +; CHECK: ret float %a + ret float %ret +} + ; fadd nsz X, 0 ==> X ; CHECK-LABEL: @nofold_fadd_x_0( define float @nofold_fadd_x_0(float %a) { |
