if (Instruction *FoldedMul = foldOpWithConstantIntoOperand(I))
return FoldedMul;
+ // -X * C --> X * -C
+ Value *X;
+ if (match(Op0, m_FNeg(m_Value(X))))
+ return BinaryOperator::CreateFMulFMF(X, ConstantExpr::getFNeg(C), &I);
+
// (fmul X, -1.0) --> (fsub -0.0, X)
if (match(C, m_SpecificFP(-1.0))) {
Constant *NegZero = ConstantFP::getNegativeZero(Op1->getType());
}
}
+ // -X * -Y --> X * Y
+ Value *X, *Y;
+ if (match(Op0, m_FNeg(m_Value(X))) && match(Op1, m_FNeg(m_Value(Y))))
+ return BinaryOperator::CreateFMulFMF(X, Y, &I);
+
+ // Sink negation: -X * Y --> -(X * Y)
+ if (match(Op0, m_OneUse(m_FNeg(m_Value(X)))))
+ return BinaryOperator::CreateFNegFMF(Builder.CreateFMulFMF(X, Op1, &I), &I);
+
+ // Sink negation: Y * -X --> -(X * Y)
+ if (match(Op1, m_OneUse(m_FNeg(m_Value(X)))))
+ return BinaryOperator::CreateFNegFMF(Builder.CreateFMulFMF(X, Op0, &I), &I);
+
// Handle symmetric situation in a 2-iteration loop
Value *Opnd0 = Op0;
Value *Opnd1 = Op1;
for (int i = 0; i < 2; i++) {
- bool IgnoreZeroSign = I.hasNoSignedZeros();
- if (BinaryOperator::isFNeg(Opnd0, IgnoreZeroSign)) {
- BuilderTy::FastMathFlagGuard Guard(Builder);
- Builder.setFastMathFlags(I.getFastMathFlags());
-
- Value *N0 = dyn_castFNegVal(Opnd0, IgnoreZeroSign);
- Value *N1 = dyn_castFNegVal(Opnd1, IgnoreZeroSign);
-
- // -X * -Y => X*Y
- if (N1) {
- Value *FMul = Builder.CreateFMul(N0, N1);
- FMul->takeName(&I);
- return replaceInstUsesWith(I, FMul);
- }
-
- if (Opnd0->hasOneUse()) {
- // -X * Y => -(X*Y) (Promote negation as high as possible)
- Value *T = Builder.CreateFMul(N0, Opnd1);
- Value *Neg = Builder.CreateFNeg(T);
- Neg->takeName(&I);
- return replaceInstUsesWith(I, Neg);
- }
- }
-
// Handle specials cases for FMul with selects feeding the operation
if (Value *V = SimplifySelectsFeedingBinaryOp(I, Op0, Op1))
return replaceInstUsesWith(I, V);