1; RUN: opt < %s -reassociate -constprop -instcombine -S | FileCheck %s
2
3define float @test1(float %A, float %B) {
4; CHECK-LABEL: test1
5; CHECK-NEXT: %W = fadd float %B, 5.000000e+00
6; CHECK-NEXT: %X = fadd float %A, -7.000000e+00
7; CHECK-NEXT: %Y = fsub float %X, %W
8; CHECK-NEXT: %Z = fadd float %Y, 1.200000e+01
9; CHECK-NEXT: ret float %Z
10
11  %W = fadd float 5.0, %B
12  %X = fadd float -7.0, %A
13  %Y = fsub float %X, %W
14  %Z = fadd float %Y, 12.0
15  ret float %Z
16}
17
18; With sub reassociation, constant folding can eliminate all of the constants.
19define float @test2(float %A, float %B) {
20; CHECK-LABEL: test2
21; CHECK-NEXT: %Z = fsub fast float %A, %B
22; CHECK-NEXT: ret float %Z
23
24  %W = fadd fast float %B, 5.000000e+00
25  %X = fadd fast float %A, -7.000000e+00
26  %Y = fsub fast float %X, %W
27  %Z = fadd fast float %Y, 1.200000e+01
28  ret float %Z
29
30}
31
32define float @test3(float %A, float %B, float %C, float %D) {
33; CHECK-LABEL: test3
34; CHECK-NEXT: %M = fadd float %A, 1.200000e+01
35; CHECK-NEXT: %N = fadd float %M, %B
36; CHECK-NEXT: %O = fadd float %N, %C
37; CHECK-NEXT: %P = fsub float %D, %O
38; CHECK-NEXT: %Q = fadd float %P, 1.200000e+01
39; CHECK-NEXT: ret float %Q
40
41  %M = fadd float %A, 1.200000e+01
42  %N = fadd float %M, %B
43  %O = fadd float %N, %C
44  %P = fsub float %D, %O
45  %Q = fadd float %P, 1.200000e+01
46  ret float %Q
47}
48
49; With sub reassociation, constant folding can eliminate the two 12 constants.
50define float @test4(float %A, float %B, float %C, float %D) {
51; CHECK-LABEL: test4
52; CHECK-NEXT: %B.neg = fsub fast float -0.000000e+00, %B
53; CHECK-NEXT: %O.neg = fsub fast float %B.neg, %A
54; CHECK-NEXT: %P = fsub fast float %O.neg, %C
55; CHECK-NEXT: %Q = fadd fast float %P, %D
56; CHECK-NEXT: ret float %Q
57
58; FIXME: InstCombine should be able to get us to the following:
59; %sum = fadd fast float %B, %A
60; %sum1 = fadd fast float %sum, %C
61; %Q = fsub fast float %D, %sum1
62; ret i32 %Q
63
64  %M = fadd fast float 1.200000e+01, %A
65  %N = fadd fast float %M, %B
66  %O = fadd fast float %N, %C
67  %P = fsub fast float %D, %O
68  %Q = fadd fast float 1.200000e+01, %P
69  ret float %Q
70}
71