1; RUN: opt -instcombine -S %s -o - | FileCheck %s
2
3; In this example, the cast from i8* to i32* becomes trivially dead. We should
4; salvage its debug info.
5
6; C source:
7; void use_as_void(void *);
8; void f(void *p) {
9;   int *q = (int *)p;
10;   use_as_void(q);
11; }
12
13; ModuleID = '<stdin>'
14source_filename = "t.c"
15target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
16target triple = "x86_64-pc-windows-msvc19.11.25508"
17
18; Function Attrs: nounwind uwtable
19define void @f(i8* %p) !dbg !11 {
20entry:
21  call void @llvm.dbg.value(metadata i8* %p, metadata !16, metadata !DIExpression()), !dbg !18
22  %0 = bitcast i8* %p to i32*, !dbg !19
23  call void @llvm.dbg.value(metadata i32* %0, metadata !17, metadata !DIExpression()), !dbg !20
24  %1 = bitcast i32* %0 to i8*, !dbg !21
25  call void @use_as_void(i8* %1), !dbg !22
26  ret void, !dbg !23
27}
28
29; CHECK-LABEL: define void @f(i8* %p)
30; CHECK: call void @llvm.dbg.value(metadata i8* %p, metadata ![[P_VAR:[0-9]+]], metadata !DIExpression())
31; CHECK-NOT: bitcast
32; CHECK: call void @llvm.dbg.value(metadata i8* %p, metadata ![[Q_VAR:[0-9]+]], metadata !DIExpression())
33; CHECK-NOT: bitcast
34; CHECK: ret void
35
36; CHECK: ![[P_VAR]] = !DILocalVariable(name: "p", {{.*}})
37; CHECK: ![[Q_VAR]] = !DILocalVariable(name: "q", {{.*}})
38
39declare void @use_as_void(i8*)
40
41declare void @llvm.dbg.value(metadata, metadata, metadata)
42
43!llvm.dbg.cu = !{!0}
44!llvm.module.flags = !{!6, !7, !8, !9}
45!llvm.ident = !{!10}
46
47!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3)
48!1 = !DIFile(filename: "t.c", directory: "C:\5Csrc\5Cllvm-project\5Cbuild", checksumkind: CSK_MD5, checksum: "56c40617ada23a8cccbd9a16bcec57af")
49!2 = !{}
50!3 = !{!4}
51!4 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !5, size: 64)
52!5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
53!6 = !{i32 2, !"CodeView", i32 1}
54!7 = !{i32 2, !"Debug Info Version", i32 3}
55!8 = !{i32 1, !"wchar_size", i32 2}
56!9 = !{i32 7, !"PIC Level", i32 2}
57!10 = !{!"clang version 6.0.0 "}
58!11 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 2, type: !12, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !15)
59!12 = !DISubroutineType(types: !13)
60!13 = !{null, !14}
61!14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
62!15 = !{!16, !17}
63!16 = !DILocalVariable(name: "p", arg: 1, scope: !11, file: !1, line: 2, type: !14)
64!17 = !DILocalVariable(name: "q", scope: !11, file: !1, line: 3, type: !4)
65!18 = !DILocation(line: 2, column: 14, scope: !11)
66!19 = !DILocation(line: 3, column: 12, scope: !11)
67!20 = !DILocation(line: 3, column: 8, scope: !11)
68!21 = !DILocation(line: 4, column: 15, scope: !11)
69!22 = !DILocation(line: 4, column: 3, scope: !11)
70!23 = !DILocation(line: 5, column: 1, scope: !11)
71