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
61
62
63
64
|
; RUN: opt < %s -basicaa -sink -S | FileCheck %s
@A = external global i32
@B = external global i32
; Sink should sink the load past the store (which doesn't overlap) into
; the block that uses it.
; CHECK-LABEL: @foo(
; CHECK: true:
; CHECK-NEXT: %l = load i32* @A
; CHECK-NEXT: ret i32 %l
define i32 @foo(i1 %z) {
%l = load i32* @A
store i32 0, i32* @B
br i1 %z, label %true, label %false
true:
ret i32 %l
false:
ret i32 0
}
; But don't sink load volatiles...
; CHECK-LABEL: @foo2(
; CHECK: load volatile
; CHECK-NEXT: store i32
define i32 @foo2(i1 %z) {
%l = load volatile i32* @A
store i32 0, i32* @B
br i1 %z, label %true, label %false
true:
ret i32 %l
false:
ret i32 0
}
; Sink to the nearest post-dominator
; CHECK-LABEL: @diamond(
; CHECK: X:
; CHECK-NEXT: phi
; CHECK-NEXT: mul nsw
; CHECK-NEXT: sub
define i32 @diamond(i32 %a, i32 %b, i32 %c) {
%1 = mul nsw i32 %c, %b
%2 = icmp sgt i32 %a, 0
br i1 %2, label %B0, label %B1
B0: ; preds = %0
br label %X
B1: ; preds = %0
br label %X
X: ; preds = %5, %3
%.01 = phi i32 [ %c, %B0 ], [ %a, %B1 ]
%R = sub i32 %1, %.01
ret i32 %R
}
|
