1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
; RUN: opt < %s -instsimplify -S | FileCheck %s
; PR8862
; CHECK-LABEL: @shift1(
; CHECK: ret i32 %A
define i32 @shift1(i32 %A, i32 %B) {
%C = lshr exact i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
; CHECK-LABEL: @shift2(
; CHECK: lshr
; CHECK: ret i32 %D
define i32 @shift2(i32 %A, i32 %B) {
%C = lshr i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
; CHECK-LABEL: @shift3(
; CHECK: ret i32 %A
define i32 @shift3(i32 %A, i32 %B) {
%C = ashr exact i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
; CHECK-LABEL: @shift4(
; CHECK: ret i32 %A
define i32 @shift4(i32 %A, i32 %B) {
%C = shl nuw i32 %A, %B
%D = lshr i32 %C, %B
ret i32 %D
}
; CHECK-LABEL: @shift5(
; CHECK: ret i32 %A
define i32 @shift5(i32 %A, i32 %B) {
%C = shl nsw i32 %A, %B
%D = ashr i32 %C, %B
ret i32 %D
}
; CHECK-LABEL: @div1(
; CHECK: ret i32 0
define i32 @div1(i32 %V) {
%A = udiv i32 %V, -2147483648
%B = udiv i32 %A, -2147483648
ret i32 %B
}
; CHECK-LABEL: @div2(
; CHECK-NOT: ret i32 0
define i32 @div2(i32 %V) {
%A = sdiv i32 %V, -1
%B = sdiv i32 %A, -2147483648
ret i32 %B
}
|
