xref: /llvm-project/llvm/test/Transforms/MemCpyOpt/load-store-to-memcpy.ll (revision a11faeed446882a81e79d780125d93e7199df645)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -passes=memcpyopt -S %s -verify-memoryssa | FileCheck %s
3
4%T = type { i8, i32 }
5
6; A global constant of %T
7@C = external constant %T
8
9; Ensure load-store forwarding of an aggregate is interpreted as
10; a memmove when the source and dest may alias
11define void @test_memmove(ptr align 8 %a, ptr align 16 %b) {
12; CHECK-LABEL: @test_memmove(
13; CHECK-NEXT:    call void @llvm.memmove.p0.p0.i64(ptr align 16 [[B:%.*]], ptr align 8 [[A:%.*]], i64 8, i1 false)
14; CHECK-NEXT:    ret void
15;
16  %val = load %T, ptr %a, align 8
17  store %T %val, ptr %b, align 16
18  ret void
19}
20
21; Ensure load-store forwarding of an aggregate is interpreted as
22; a memcpy when the source and dest do not alias
23define void @test_memcpy(ptr noalias align 8 %a, ptr noalias align 16 %b) {
24; CHECK-LABEL: @test_memcpy(
25; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 16 [[B:%.*]], ptr align 8 [[A:%.*]], i64 8, i1 false)
26; CHECK-NEXT:    ret void
27;
28  %val = load %T, ptr %a, align 8
29  store %T %val, ptr %b, align 16
30  ret void
31}
32
33define void @test_memcpy_constant(ptr %d) {
34; CHECK-LABEL: @test_memcpy_constant(
35; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 16 [[D:%.*]], ptr align 8 @C, i64 8, i1 false)
36; CHECK-NEXT:    ret void
37;
38  %val = load %T, ptr @C, align 8
39  store %T %val, ptr %d, align 16
40  ret void
41}
42
43; memcpy(%d, %a) should not be generated since store2 may-aliases load %a.
44define void @f(ptr %a, ptr %b, ptr %c, ptr %d) {
45; CHECK-LABEL: @f(
46; CHECK-NEXT:    [[VAL:%.*]] = load [[T:%.*]], ptr [[A:%.*]], align 4, !alias.scope !0
47; CHECK-NEXT:    store [[T]] { i8 23, i32 23 }, ptr [[B:%.*]], align 4, !alias.scope !3
48; CHECK-NEXT:    store [[T]] { i8 44, i32 44 }, ptr [[C:%.*]], align 4, !alias.scope !6, !noalias !3
49; CHECK-NEXT:    store [[T]] [[VAL]], ptr [[D:%.*]], align 4, !alias.scope !9, !noalias !12
50; CHECK-NEXT:    ret void
51;
52  %val = load %T, ptr %a, !alias.scope !{!10}
53
54  ; store1 may-aliases the load
55  store %T { i8 23, i32 23 }, ptr %b, !alias.scope !{!11}
56
57  ; store2 may-aliases the load and store3
58  store %T { i8 44, i32 44 }, ptr %c, !alias.scope !{!12}, !noalias !{!11}
59
60  ; store3
61  store %T %val, ptr %d, !alias.scope !{!13}, !noalias !{!10, !11}
62  ret void
63}
64
65!0 = !{!0}
66!1 = !{!1}
67!2 = !{!2}
68!3 = !{!3}
69
70!10 = !{ !10, !0 }
71!11 = !{ !11, !1 }
72!12 = !{ !12, !2 }
73!13 = !{ !13, !3 }
74