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
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
; RUN: opt < %s -tbaa -basicaa -aa-eval -evaluate-tbaa -print-no-aliases -print-may-aliases -disable-output 2>&1 | FileCheck %s
; Generated with "clang -cc1 -disable-llvm-optzns -O1 -emit-llvm"
; #include <new>
; struct Foo { long i; };
; struct Bar { void *p; };
; long foo(int n) {
; Foo *f = new Foo;
; f->i = 1;
; for (int i=0; i<n; ++i) {
; Bar *b = new (f) Bar;
; b->p = 0;
; f = new (f) Foo;
; f->i = i;
; }
; return f->i;
; }
; Basic AA says MayAlias, TBAA says NoAlias
; CHECK: MayAlias: i64* %i5, i8** %p
; CHECK: NoAlias: store i64 %conv, i64* %i5, align 8, !tbaa !4 <-> store i8* null, i8** %p, align 8, !tbaa !3
%struct.Foo = type { i64 }
%struct.Bar = type { i8* }
define i64 @_Z3fooi(i32 %n) #0 {
entry:
%n.addr = alloca i32, align 4
%f = alloca %struct.Foo*, align 8
%i1 = alloca i32, align 4
%b = alloca %struct.Bar*, align 8
store i32 %n, i32* %n.addr, align 4, !tbaa !0
%call = call noalias i8* @_Znwm(i64 8)
%0 = bitcast i8* %call to %struct.Foo*
store %struct.Foo* %0, %struct.Foo** %f, align 8, !tbaa !3
%1 = load %struct.Foo** %f, align 8, !tbaa !3
%i = getelementptr inbounds %struct.Foo* %1, i32 0, i32 0
store i64 1, i64* %i, align 8, !tbaa !4
store i32 0, i32* %i1, align 4, !tbaa !0
br label %for.cond
for.cond:
%2 = load i32* %i1, align 4, !tbaa !0
%3 = load i32* %n.addr, align 4, !tbaa !0
%cmp = icmp slt i32 %2, %3
br i1 %cmp, label %for.body, label %for.end
for.body:
%4 = load %struct.Foo** %f, align 8, !tbaa !3
%5 = bitcast %struct.Foo* %4 to i8*
%new.isnull = icmp eq i8* %5, null
br i1 %new.isnull, label %new.cont, label %new.notnull
new.notnull:
%6 = bitcast i8* %5 to %struct.Bar*
br label %new.cont
new.cont:
%7 = phi %struct.Bar* [ %6, %new.notnull ], [ null, %for.body ]
store %struct.Bar* %7, %struct.Bar** %b, align 8, !tbaa !3
%8 = load %struct.Bar** %b, align 8, !tbaa !3
%p = getelementptr inbounds %struct.Bar* %8, i32 0, i32 0
store i8* null, i8** %p, align 8, !tbaa !3
%9 = load %struct.Foo** %f, align 8, !tbaa !3
%10 = bitcast %struct.Foo* %9 to i8*
%new.isnull2 = icmp eq i8* %10, null
br i1 %new.isnull2, label %new.cont4, label %new.notnull3
new.notnull3:
%11 = bitcast i8* %10 to %struct.Foo*
br label %new.cont4
new.cont4:
%12 = phi %struct.Foo* [ %11, %new.notnull3 ], [ null, %new.cont ]
store %struct.Foo* %12, %struct.Foo** %f, align 8, !tbaa !3
%13 = load i32* %i1, align 4, !tbaa !0
%conv = sext i32 %13 to i64
%14 = load %struct.Foo** %f, align 8, !tbaa !3
%i5 = getelementptr inbounds %struct.Foo* %14, i32 0, i32 0
store i64 %conv, i64* %i5, align 8, !tbaa !4
br label %for.inc
for.inc:
%15 = load i32* %i1, align 4, !tbaa !0
%inc = add nsw i32 %15, 1
store i32 %inc, i32* %i1, align 4, !tbaa !0
br label %for.cond
for.end:
%16 = load %struct.Foo** %f, align 8, !tbaa !3
%i6 = getelementptr inbounds %struct.Foo* %16, i32 0, i32 0
%17 = load i64* %i6, align 8, !tbaa !4
ret i64 %17
}
declare noalias i8* @_Znwm(i64)
attributes #0 = { nounwind }
!0 = metadata !{metadata !"int", metadata !1}
!1 = metadata !{metadata !"omnipotent char", metadata !2}
!2 = metadata !{metadata !"Simple C/C++ TBAA"}
!3 = metadata !{metadata !"any pointer", metadata !1}
!4 = metadata !{metadata !"long", metadata !1}
|
