1; RUN: opt -S -instcombine < %s | FileCheck %s
2
3; (-0.0 - X) * C => X * -C
4define float @test1(float %x) {
5  %sub = fsub float -0.000000e+00, %x
6  %mul = fmul float %sub, 2.0e+1
7  ret float %mul
8
9; CHECK-LABEL: @test1(
10; CHECK: fmul float %x, -2.000000e+01
11}
12
13; (0.0 - X) * C => X * -C
14define float @test2(float %x) {
15  %sub = fsub nsz float 0.000000e+00, %x
16  %mul = fmul float %sub, 2.0e+1
17  ret float %mul
18
19; CHECK-LABEL: @test2(
20; CHECK: fmul float %x, -2.000000e+01
21}
22
23; (-0.0 - X) * (-0.0 - Y) => X * Y
24define float @test3(float %x, float %y) {
25  %sub1 = fsub float -0.000000e+00, %x
26  %sub2 = fsub float -0.000000e+00, %y
27  %mul = fmul fast float %sub1, %sub2
28  ret float %mul
29; CHECK-LABEL: @test3(
30; CHECK: fmul fast float %x, %y
31}
32
33; (0.0 - X) * (0.0 - Y) => X * Y
34define float @test4(float %x, float %y) {
35  %sub1 = fsub nsz float 0.000000e+00, %x
36  %sub2 = fsub nsz float 0.000000e+00, %y
37  %mul = fmul float %sub1, %sub2
38  ret float %mul
39; CHECK-LABEL: @test4(
40; CHECK: fmul float %x, %y
41}
42
43; (-0.0 - X) * Y => -0.0 - (X * Y)
44define float @test5(float %x, float %y) {
45  %sub1 = fsub float -0.000000e+00, %x
46  %mul = fmul float %sub1, %y
47  ret float %mul
48; CHECK-LABEL: @test5(
49; CHECK: %1 = fmul float %x, %y
50; CHECK: %mul = fsub float -0.000000e+00, %1
51}
52
53; (0.0 - X) * Y => 0.0 - (X * Y)
54define float @test6(float %x, float %y) {
55  %sub1 = fsub nsz float 0.000000e+00, %x
56  %mul = fmul float %sub1, %y
57  ret float %mul
58; CHECK-LABEL: @test6(
59; CHECK: %1 = fmul float %x, %y
60; CHECK: %mul = fsub float -0.000000e+00, %1
61}
62
63; "(-0.0 - X) * Y => -0.0 - (X * Y)" is disabled if expression "-0.0 - X"
64; has multiple uses.
65define float @test7(float %x, float %y) {
66  %sub1 = fsub float -0.000000e+00, %x
67  %mul = fmul float %sub1, %y
68  %mul2 = fmul float %mul, %sub1
69  ret float %mul2
70; CHECK-LABEL: @test7(
71; CHECK: fsub float -0.000000e+00, %x
72}
73
74; Don't crash when attempting to cast a constant FMul to an instruction.
75define void @test8(i32* %inout) {
76entry:
77  %0 = load i32, i32* %inout, align 4
78  %conv = uitofp i32 %0 to float
79  %vecinit = insertelement <4 x float> <float 0.000000e+00, float 0.000000e+00, float 0.000000e+00, float undef>, float %conv, i32 3
80  %sub = fsub <4 x float> <float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00>, %vecinit
81  %1 = shufflevector <4 x float> %sub, <4 x float> undef, <4 x i32> <i32 1, i32 1, i32 1, i32 1>
82  %mul = fmul <4 x float> zeroinitializer, %1
83  br label %for.cond
84
85for.cond:                                         ; preds = %for.body, %entry
86  %local_var_7.0 = phi <4 x float> [ %mul, %entry ], [ %2, %for.body ]
87  br i1 undef, label %for.body, label %for.end
88
89for.body:                                         ; preds = %for.cond
90  %2 = insertelement <4 x float> %local_var_7.0, float 0.000000e+00, i32 2
91  br label %for.cond
92
93for.end:                                          ; preds = %for.cond
94  ret void
95}
96
97; X * -1.0 => -0.0 - X
98define float @test9(float %x) {
99  %mul = fmul float %x, -1.0
100  ret float %mul
101
102; CHECK-LABEL: @test9(
103; CHECK-NOT: fmul
104; CHECK: fsub
105}
106
107; PR18532
108define <4 x float> @test10(<4 x float> %x) {
109  %mul = fmul <4 x float> %x, <float -1.0, float -1.0, float -1.0, float -1.0>
110  ret <4 x float> %mul
111
112; CHECK-LABEL: @test10(
113; CHECK-NOT: fmul
114; CHECK: fsub
115}
116
117define float @test11(float %x, float %y) {
118  %a = fadd fast float %x, 1.0
119  %b = fadd fast float %y, 2.0
120  %c = fadd fast float %a, %b
121  ret float %c
122; CHECK-LABEL: @test11(
123; CHECK-NOT: fadd float
124; CHECK: fadd fast float
125}
126
127; PR21126: http://llvm.org/bugs/show_bug.cgi?id=21126
128; With unsafe/fast math, sqrt(X) * sqrt(X) is just X.
129declare double @llvm.sqrt.f64(double)
130
131define double @sqrt_squared1(double %f) {
132  %sqrt = call double @llvm.sqrt.f64(double %f)
133  %mul = fmul fast double %sqrt, %sqrt
134  ret double %mul
135; CHECK-LABEL: @sqrt_squared1(
136; CHECK-NEXT: ret double %f
137}
138
139; With unsafe/fast math, sqrt(X) * sqrt(X) is just X,
140; but make sure another use of the sqrt is intact.
141; Note that the remaining fmul is altered but is not 'fast'
142; itself because it was not marked 'fast' originally.
143; Thus, we have an overall fast result, but no more indication of
144; 'fast'ness in the code.
145define double @sqrt_squared2(double %f) {
146  %sqrt = call double @llvm.sqrt.f64(double %f)
147  %mul1 = fmul fast double %sqrt, %sqrt
148  %mul2 = fmul double %mul1, %sqrt
149  ret double %mul2
150; CHECK-LABEL: @sqrt_squared2(
151; CHECK-NEXT: %sqrt = call double @llvm.sqrt.f64(double %f)
152; CHECK-NEXT: %mul2 = fmul double %sqrt, %f
153; CHECK-NEXT: ret double %mul2
154}
155