Refactor logic and add additional tests

Author: SahilPatidar

llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp

@@ -2759,9 +2759,10 @@ static Instruction *foldFNegIntoConstant(Instruction &I, const DataLayout &DL) {
  // -(X * C) --> X * (-C)
  if (match(FNegOp, m_FMul(m_Value(X), m_Constant(C))))
  if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL)) {
- FastMathFlags Flag = I.getFastMathFlags() | FNegOp->getFastMathFlags();
- Flag.setNoInfs(I.getFastMathFlags().noInfs() &&
- FNegOp->getFastMathFlags().noInfs());
+ FastMathFlags FMF = I.getFastMathFlags();
+ FastMathFlags OpFMF = FNegOp->getFastMathFlags();
+ FastMathFlags Flag = FMF | OpFMF;
+ Flag.setNoInfs(FMF.noInfs() && OpFMF.noInfs());
  return BinaryOperator::CreateFMulFMF(X, NegC, Flag);
  }
  // -(X / C) --> X / (-C)

llvm/test/Transforms/InstCombine/fneg.ll

@@ -1233,4 +1233,14 @@ define <2 x float> @test_fneg_nnan_ninf_mul_with_vec_const(<2 x float> %a) {
  ret <2 x float> %f2
 }
 
+define <2 x float> @test_fneg_nnan_ninf_mul_ninf_with_vec_const(<2 x float> %a) {
+; CHECK-LABEL: @test_fneg_nnan_ninf_mul_ninf_with_vec_const(
+; CHECK-NEXT: [[F2:%.*]] = fmul nnan ninf <2 x float> [[A:%.*]], <float -0.000000e+00, float 0.000000e+00>
+; CHECK-NEXT: ret <2 x float> [[F2]]
+;
+ %f1 = fmul ninf <2 x float> %a, <float 0.000000, float -0.000000>
+ %f2 = fneg nnan ninf <2 x float> %f1
+ ret <2 x float> %f2
+}
+
 !0 = !{}