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
|
; RUN: llvm-as < %s | llvm-dis > %t1.ll
; RUN: llvm-as %t1.ll -o - | llvm-dis > %t2.ll
; RUN: diff %t1.ll %t2.ll
;; This is an irreducible flow graph
define void @irreducible(i1 %cond) {
br i1 %cond, label %X, label %Y
X: ; preds = %Y, %0
br label %Y
Y: ; preds = %X, %0
br label %X
}
;; This is a pair of loops that share the same header
define void @sharedheader(i1 %cond) {
br label %A
A: ; preds = %Y, %X, %0
br i1 %cond, label %X, label %Y
X: ; preds = %A
br label %A
Y: ; preds = %A
br label %A
}
;; This is a simple nested loop
define void @nested(i1 %cond1, i1 %cond2, i1 %cond3) {
br label %Loop1
Loop1: ; preds = %L2Exit, %0
br label %Loop2
Loop2: ; preds = %L3Exit, %Loop1
br label %Loop3
Loop3: ; preds = %Loop3, %Loop2
br i1 %cond3, label %Loop3, label %L3Exit
L3Exit: ; preds = %Loop3
br i1 %cond2, label %Loop2, label %L2Exit
L2Exit: ; preds = %L3Exit
br i1 %cond1, label %Loop1, label %L1Exit
L1Exit: ; preds = %L2Exit
ret void
}
|