1; RUN: opt -S -memcpyopt < %s | FileCheck %s
2
3; PR40118: BasicAA didn't realize that stackrestore ends the lifetime of
4; unescaped dynamic allocas, such as those that might come from inalloca.
5
6source_filename = "t.cpp"
7target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
8target triple = "i686-unknown-windows-msvc19.14.26433"
9
10@str = internal constant [9 x i8] c"abcdxxxxx"
11
12
13; Test that we can propagate memcpy through an unescaped dynamic alloca across
14; a call to @external.
15
16define i32 @test_norestore(i32 %n) {
17  %tmpmem = alloca [10 x i8], align 4
18  %tmp = getelementptr inbounds [10 x i8], [10 x i8]* %tmpmem, i32 0, i32 0
19
20  ; Make a dynamic alloca, initialize it.
21  %p = alloca i8, i32 %n, align 4
22  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* align 1 getelementptr inbounds ([9 x i8], [9 x i8]* @str, i32 0, i32 0), i32 9, i1 false)
23
24  ; This extra byte exists to prevent memcpyopt from propagating @str.
25  %p10 = getelementptr inbounds i8, i8* %p, i32 9
26  store i8 0, i8* %p10
27
28  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %tmp, i8* %p, i32 10, i1 false)
29  call void @external()
30  %heap = call i8* @malloc(i32 9)
31  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %heap, i8* %tmp, i32 9, i1 false)
32  call void @useit(i8* %heap)
33  ret i32 0
34}
35
36; CHECK-LABEL: define i32 @test_norestore(i32 %n)
37; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* align 1 getelementptr inbounds ([9 x i8], [9 x i8]* @str, i32 0, i32 0), i32 9, i1 false)
38; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %tmp, i8* %p, i32 10, i1 false)
39; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %heap, i8* %p, i32 9, i1 false)
40
41
42; Do not propagate memcpy from %p across the stackrestore.
43
44define i32 @test_stackrestore() {
45  %tmpmem = alloca [10 x i8], align 4
46  %tmp = getelementptr inbounds [10 x i8], [10 x i8]* %tmpmem, i32 0, i32 0
47  %inalloca.save = tail call i8* @llvm.stacksave()
48  %argmem = alloca inalloca [10 x i8], align 4
49  %p = getelementptr inbounds [10 x i8], [10 x i8]* %argmem, i32 0, i32 0
50  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* align 1 getelementptr inbounds ([9 x i8], [9 x i8]* @str, i32 0, i32 0), i32 9, i1 false)
51
52  ; This extra byte exists to prevent memcpyopt from propagating @str.
53  %p10 = getelementptr inbounds [10 x i8], [10 x i8]* %argmem, i32 0, i32 9
54  store i8 0, i8* %p10
55
56  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %tmp, i8* %p, i32 10, i1 false)
57  call void @llvm.stackrestore(i8* %inalloca.save)
58  %heap = call i8* @malloc(i32 9)
59  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %heap, i8* %tmp, i32 9, i1 false)
60  call void @useit(i8* %heap)
61  ret i32 0
62}
63
64; CHECK-LABEL: define i32 @test_stackrestore()
65; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* align 1 getelementptr inbounds ([9 x i8], [9 x i8]* @str, i32 0, i32 0), i32 9, i1 false)
66; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %tmp, i8* %p, i32 10, i1 false)
67; CHECK: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %heap, i8* %tmp, i32 9, i1 false)
68
69declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture writeonly, i8* nocapture readonly, i32, i1)
70declare i8* @llvm.stacksave()
71declare void @llvm.stackrestore(i8*)
72declare i8* @malloc(i32)
73declare void @useit(i8*)
74declare void @external()
75