1; RUN: llc < %s -filetype=obj | llvm-dwarfdump -v - --debug-info | FileCheck %s
2;
3; IR module created as follows:
4;   clang -emit-llvm -S -O2 foo.cpp -o foo.ll -g
5;   clang -emit-llvm -S -O2 bar.cpp -o bar.ll -gmlt
6;   llvm-link foo.ll bar.ll -S -o linked.ll
7;   opt -std-link-opts linked.ll -S -o opt.ll
8; --- foo.cpp ---
9; void f();
10; void foo(int param) {
11;   if (param) f();
12; }
13; --- bar.cpp ---
14; void foo(int);
15; void bar() {
16;   foo(0);
17; }
18; ---
19; The point is that bar() is compiled -gmlt and calls foo() with a constant 0.
20; foo() is compiled -g and gets inlined into bar(); foo's body is then
21; optimized away, leaving only a dbg.value call describing the inlined copy
22; of 'param', which should be benign.
23; That is, the compile-unit for bar.cpp should have nothing in it.
24; PR31437.
25
26; foo.cpp's unit comes first; skip past it, second unit should be empty.
27; CHECK:     DW_TAG_compile_unit
28; CHECK-NOT: {{DW_TAG|NULL}}
29; CHECK:     DW_AT_name {{.*}} "foo.cpp"
30; CHECK:     DW_TAG_compile_unit
31; CHECK-NOT: DW_TAG
32
33; ModuleID = 'linked.ll'
34source_filename = "llvm-link"
35target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
36target triple = "x86_64-unknown-linux-gnu"
37
38; Function Attrs: uwtable
39define void @_Z3fooi(i32 %param) local_unnamed_addr #0 !dbg !8 {
40entry:
41  tail call void @llvm.dbg.value(metadata i32 %param, metadata !13, metadata !14), !dbg !15
42  %tobool = icmp eq i32 %param, 0, !dbg !16
43  br i1 %tobool, label %if.end, label %if.then, !dbg !18
44
45if.then:                                          ; preds = %entry
46  tail call void @_Z1fv(), !dbg !19
47  br label %if.end, !dbg !19
48
49if.end:                                           ; preds = %if.then, %entry
50  ret void, !dbg !21
51}
52
53; Function Attrs: nounwind readnone
54declare void @llvm.dbg.value(metadata, metadata, metadata) #1
55
56declare void @_Z1fv() local_unnamed_addr #2
57
58; Function Attrs: nounwind readnone uwtable
59define void @_Z3barv() local_unnamed_addr #3 !dbg !22 {
60entry:
61  tail call void @llvm.dbg.value(metadata i32 0, metadata !13, metadata !14), !dbg !24
62  ret void, !dbg !26
63}
64
65attributes #0 = { uwtable }
66attributes #1 = { nounwind readnone }
67attributes #2 = { nounwind }
68attributes #3 = { nounwind readnone uwtable }
69
70!llvm.dbg.cu = !{!0, !3}
71!llvm.ident = !{!5, !5}
72!llvm.module.flags = !{!6, !7}
73
74!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 5.0.0 (trunk 293745)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
75!1 = !DIFile(filename: "foo.cpp", directory: "/home/probinson/projects/scratch/pr31437")
76!2 = !{}
77!3 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !4, producer: "clang version 5.0.0 (trunk 293745)", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2)
78!4 = !DIFile(filename: "bar.cpp", directory: "/home/probinson/projects/scratch/pr31437")
79!5 = !{!"clang version 5.0.0 (trunk 293745)"}
80!6 = !{i32 2, !"Dwarf Version", i32 4}
81!7 = !{i32 2, !"Debug Info Version", i32 3}
82!8 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooi", scope: !1, file: !1, line: 2, type: !9, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !12)
83!9 = !DISubroutineType(types: !10)
84!10 = !{null, !11}
85!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
86!12 = !{!13}
87!13 = !DILocalVariable(name: "param", arg: 1, scope: !8, file: !1, line: 2, type: !11)
88!14 = !DIExpression()
89!15 = !DILocation(line: 2, column: 14, scope: !8)
90!16 = !DILocation(line: 3, column: 7, scope: !17)
91!17 = distinct !DILexicalBlock(scope: !8, file: !1, line: 3, column: 7)
92!18 = !DILocation(line: 3, column: 7, scope: !8)
93!19 = !DILocation(line: 3, column: 14, scope: !20)
94!20 = !DILexicalBlockFile(scope: !17, file: !1, discriminator: 1)
95!21 = !DILocation(line: 4, column: 1, scope: !8)
96!22 = distinct !DISubprogram(name: "bar", scope: !4, file: !4, line: 2, type: !23, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !3, retainedNodes: !2)
97!23 = !DISubroutineType(types: !2)
98!24 = !DILocation(line: 2, column: 14, scope: !8, inlinedAt: !25)
99!25 = distinct !DILocation(line: 3, column: 3, scope: !22)
100!26 = !DILocation(line: 4, column: 1, scope: !22)
101