1; A store or load cannot alias a global if the accessed amount is larger then
2; the global.
3
4; RUN: opt < %s -basicaa -gvn -S | FileCheck %s
5target datalayout = "E-p:64:64:64-p1:16:16:16-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
6
7@B = global i16 8
8
9; CHECK-LABEL: @test1(
10define i16 @test1(i32* %P) {
11        %X = load i16, i16* @B
12        store i32 7, i32* %P
13        %Y = load i16, i16* @B
14        %Z = sub i16 %Y, %X
15        ret i16 %Z
16; CHECK: ret i16 0
17}
18
19@B_as1 = addrspace(1) global i16 8
20
21define i16 @test1_as1(i32 addrspace(1)* %P) {
22; CHECK-LABEL: @test1_as1(
23; CHECK: ret i16 0
24  %X = load i16, i16 addrspace(1)* @B_as1
25  store i32 7, i32 addrspace(1)* %P
26  %Y = load i16, i16 addrspace(1)* @B_as1
27  %Z = sub i16 %Y, %X
28  ret i16 %Z
29}
30
31; Cannot know anything about the size of this global.
32; rdar://8813415
33@window = external global [0 x i8]
34
35; CHECK-LABEL: @test2(
36define i8 @test2(i32 %tmp79, i32 %w.2, i32 %indvar89) nounwind {
37  %tmp92 = add i32 %tmp79, %indvar89
38  %arrayidx412 = getelementptr [0 x i8], [0 x i8]* @window, i32 0, i32 %tmp92
39  %tmp93 = add i32 %w.2, %indvar89
40  %arrayidx416 = getelementptr [0 x i8], [0 x i8]* @window, i32 0, i32 %tmp93
41
42  %A = load i8, i8* %arrayidx412, align 1
43  store i8 4, i8* %arrayidx416, align 1
44
45  %B = load i8, i8* %arrayidx412, align 1
46  %C = sub i8 %A, %B
47  ret i8 %C
48
49; CHECK: %B = load i8
50; CHECK: ret i8 %C
51}
52
53