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
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -basicaa -newgvn -S | FileCheck %s
;; Most of these are borrowed from transforms/DSE/simple.ll
;; NewGVN should be able to eliminate any stores of the same value that are actually redundnat.
;; tmp5 is store of the same value to the same location as the load.
define void @test12({ i32, i32 }* %x) nounwind {
; CHECK-LABEL: @test12(
; CHECK-NEXT: [[TMP4:%.*]] = getelementptr { i32, i32 }, { i32, i32 }* [[X:%.*]], i32 0, i32 0
; CHECK-NEXT: [[TMP5:%.*]] = load i32, i32* [[TMP4]], align 4
; CHECK-NEXT: [[TMP7:%.*]] = getelementptr { i32, i32 }, { i32, i32 }* [[X]], i32 0, i32 1
; CHECK-NEXT: [[TMP8:%.*]] = load i32, i32* [[TMP7]], align 4
; CHECK-NEXT: [[TMP17:%.*]] = sub i32 0, [[TMP8]]
; CHECK-NEXT: store i32 [[TMP17]], i32* [[TMP7]], align 4
; CHECK-NEXT: ret void
;
%tmp4 = getelementptr { i32, i32 }, { i32, i32 }* %x, i32 0, i32 0
%tmp5 = load i32, i32* %tmp4, align 4
%tmp7 = getelementptr { i32, i32 }, { i32, i32 }* %x, i32 0, i32 1
%tmp8 = load i32, i32* %tmp7, align 4
%tmp17 = sub i32 0, %tmp8
store i32 %tmp5, i32* %tmp4, align 4
store i32 %tmp17, i32* %tmp7, align 4
ret void
}
; Remove redundant store if loaded value is in another block.
define i32 @test26(i1 %c, i32* %p) {
; CHECK-LABEL: @test26(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[V:%.*]] = load i32, i32* [[P:%.*]], align 4
; CHECK-NEXT: br i1 [[C:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK: bb1:
; CHECK-NEXT: br label [[BB3:%.*]]
; CHECK: bb2:
; CHECK-NEXT: br label [[BB3]]
; CHECK: bb3:
; CHECK-NEXT: ret i32 0
;
entry:
%v = load i32, i32* %p, align 4
br i1 %c, label %bb1, label %bb2
bb1:
br label %bb3
bb2:
store i32 %v, i32* %p, align 4
br label %bb3
bb3:
ret i32 0
}
declare void @unknown_func()
; Remove redundant store, which is in the same loop as the load.
define i32 @test33(i1 %c, i32* %p, i32 %i) {
; CHECK-LABEL: @test33(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[BB1:%.*]]
; CHECK: bb1:
; CHECK-NEXT: [[V:%.*]] = load i32, i32* [[P:%.*]], align 4
; CHECK-NEXT: br label [[BB2:%.*]]
; CHECK: bb2:
; CHECK-NEXT: call void @unknown_func()
; CHECK-NEXT: br i1 undef, label [[BB1]], label [[BB3:%.*]]
; CHECK: bb3:
; CHECK-NEXT: ret i32 0
;
entry:
br label %bb1
bb1:
%v = load i32, i32* %p, align 4
br label %bb2
bb2:
store i32 %v, i32* %p, align 4
; Might read and overwrite value at %p, but doesn't matter.
call void @unknown_func()
br i1 undef, label %bb1, label %bb3
bb3:
ret i32 0
}
|