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1; RUN: opt -globalopt -S < %s | FileCheck %s
2
3@G1 = internal global i32 5
4@G2 = internal global i32 5
5@G3 = internal global i32 5
6@G4 = internal global i32 5
7@G5 = internal global i32 5
8
9; CHECK-LABEL: @test1
10define internal i32 @test1() norecurse {
11; CHECK-NOT: @G1
12  store i32 4, i32* @G1
13  %a = load i32, i32* @G1
14; CHECK: ret
15  ret i32 %a
16}
17
18; The load comes before the store which makes @G2 live before the call.
19; CHECK-LABEL: @test2
20define internal i32 @test2() norecurse {
21; CHECK-NOT: %G2
22  %a = load i32, i32* @G2
23  store i32 4, i32* @G2
24; CHECK: ret
25  ret i32 %a
26}
27
28; This global is indexed by a GEP - this makes it partial alias and we bail out.
29; FIXME: We don't actually have to bail out in this case.
30
31; CHECK-LABEL: @test3
32define internal i32 @test3() norecurse {
33; CHECK-NOT: %G3
34  %x = getelementptr i32,i32* @G3, i32 0
35  %a = load i32, i32* %x
36  store i32 4, i32* @G3
37; CHECK: ret
38  ret i32 %a
39}
40
41; The global is casted away to a larger type then loaded. The store only partially
42; covers the load, so we must not demote.
43
44; CHECK-LABEL: @test4
45define internal i32 @test4() norecurse {
46; CHECK-NOT: %G4
47  store i32 4, i32* @G4
48  %x = bitcast i32* @G4 to i64*
49  %a = load i64, i64* %x
50  %b = trunc i64 %a to i32
51; CHECK: ret
52  ret i32 %b
53}
54
55; The global is casted away to a smaller type then loaded. This one is fine.
56
57; CHECK-LABEL: @test5
58define internal i32 @test5() norecurse {
59; CHECK-NOT: @G5
60  store i32 4, i32* @G5
61  %x = bitcast i32* @G5 to i16*
62  %a = load i16, i16* %x
63  %b = zext i16 %a to i32
64; CHECK: ret
65  ret i32 %b
66}
67
68define i32 @main() norecurse {
69  %a = call i32 @test1()
70  %b = call i32 @test2()
71  %c = call i32 @test3()
72  %d = call i32 @test4()
73  %e = call i32 @test5()
74
75  %x = or i32 %a, %b
76  %y = or i32 %x, %c
77  %z = or i32 %y, %d
78  %w = or i32 %z, %e
79  ret i32 %w
80}
81