[InstSimply] Add tests for simplify (fmul -x, +/-0); NFC

Author: goldsteinn

llvm/test/Transforms/InstSimplify/floating-point-arithmetic.ll

@@ -211,6 +211,53 @@ define double @fmul_nnan_ninf_nneg_n0.0_commute(i127 %x) {
   ret double %r
 }
 
+define float @src_mul_nzero_neg(float nofpclass(inf nan pzero psub pnorm) %f) {
+; CHECK-LABEL: @src_mul_nzero_neg(
+; CHECK-NEXT:    [[R:%.*]] = fmul float [[F:%.*]], -0.000000e+00
+; CHECK-NEXT:    ret float [[R]]
+;
+  %r = fmul float %f, -0.0
+  ret float %r
+}
+
+define <2 x float> @src_mul_zero_neg(<2 x float> nofpclass(inf nan pzero psub pnorm) %f) {
+; CHECK-LABEL: @src_mul_zero_neg(
+; CHECK-NEXT:    [[R:%.*]] = fmul <2 x float> zeroinitializer, [[F:%.*]]
+; CHECK-NEXT:    ret <2 x float> [[R]]
+;
+  %r = fmul <2 x float> <float 0.0, float 0.0>, %f
+  ret <2 x float> %r
+}
+
+define <2 x float> @src_mul_zero_and_nzero_neg(<2 x float> nofpclass(inf nan pzero psub pnorm) %f) {
+; CHECK-LABEL: @src_mul_zero_and_nzero_neg(
+; CHECK-NEXT:    [[R:%.*]] = fmul <2 x float> <float -0.000000e+00, float 0.000000e+00>, [[F:%.*]]
+; CHECK-NEXT:    ret <2 x float> [[R]]
+;
+  %r = fmul <2 x float> <float -0.0, float 0.0>, %f
+  ret <2 x float> %r
+}
+
+
+define float @src_muladd_zero_neg(float nofpclass(inf nan pzero psub pnorm) %f, float %add) {
+; CHECK-LABEL: @src_muladd_zero_neg(
+; CHECK-NEXT:    [[R:%.*]] = call float @llvm.fmuladd.f32(float [[F:%.*]], float 0.000000e+00, float [[ADD:%.*]])
+; CHECK-NEXT:    ret float [[R]]
+;
+  %r = call float @llvm.fmuladd.f32(float %f, float 0.0, float %add)
+  ret float %r
+}
+
+define float @src_fma_nzero_neg(float nofpclass(inf nan pzero psub pnorm) %f, float %add) {
+; CHECK-LABEL: @src_fma_nzero_neg(
+; CHECK-NEXT:    [[R:%.*]] = call float @llvm.fma.f32(float -0.000000e+00, float [[F:%.*]], float [[ADD:%.*]])
+; CHECK-NEXT:    ret float [[R]]
+;
+  %r = call float @llvm.fma.f32(float -0.0, float %f, float %add)
+  ret float %r
+}
+
+
 ; Make sure we can infer %x can't be 0 based on assumes.
 define { float, float } @test_fmul_0_assumed_finite(float %x) {
 ; CHECK-LABEL: @test_fmul_0_assumed_finite(