xref: /llvm-project/llvm/test/DebugInfo/Generic/no-empty-child-vars.ll (revision e8209b2486d8fa1a5314af0fe896b9628effa471)
1; RUN: %llc_dwarf %s -o - -filetype=obj | llvm-dwarfdump - | FileCheck %s -implicit-check-not=DW_TAG
2;
3; Issue #46473
4; XFAIL: target=sparc{{.*}}
5;
6; This tests that we do not create concrete variable DIEs for variables that
7; have no location -- for both ways that LLVM-IR can express a variable with
8; no location. It's possible to:
9;   1) Omit all dbg.values and place the variable in the subprograms retained
10;      nodes list,
11;   2) Have a dbg.value with an undef operand, and none with "real" operands.
12; Both of these should produce the same DWARF. In the two functions below
13; (qux and croix) I've modified the IR to represent both scenarios.
14;
15; Original C, LLVM-IR modified afterwards:
16;
17; int foo(int bar) {
18;   int baz = 12 + bar;
19;   return baz;
20; }
21;
22; int qux(int quux) {
23;   int xyzzy = foo(quux);
24;   return xyzzy;
25; }
26;
27; int croix(int quux) {
28;   int xyzzy = foo(quux);
29;   return xyzzy;
30; }
31;
32;; Note the implicit DW_TAG check-not in the FileCheck command line.
33; CHECK: DW_TAG_compile_unit
34;;
35;; First subprogram is attached to the plain "foo" function in the output
36;; object. It should have locations for the two variables in the function,
37;; let's be non-specific as to how.
38; CHECK:     DW_TAG_subprogram
39; CHECK:       DW_AT_abstract_origin (0x{{[0-9a-f]*}} "foo")
40; CHECK:       DW_TAG_formal_parameter
41; CHECK:         DW_AT_location
42; CHECK:       DW_TAG_variable
43; CHECK:         DW_AT_location
44;
45;; Abstract subprogram; should have plain variable declarations
46; CHECK:     DW_TAG_subprogram
47; CHECK:       DW_AT_name ("foo")
48; CHECK:       DW_TAG_formal_parameter
49; CHECK:         DW_AT_name ("bar")
50; CHECK:       DW_TAG_variable
51; CHECK:         DW_AT_name ("baz")
52;
53; CHECK:     DW_TAG_base_type
54;
55;; The copy of "foo" inlined into "qux" should have no children.
56; CHECK:     DW_TAG_subprogram
57; CHECK:       DW_AT_name ("qux")
58; CHECK:       DW_TAG_formal_parameter
59; CHECK:       DW_TAG_variable
60; CHECK:       DW_TAG_inlined_subroutine
61; CHECK:     NULL
62;
63;; Same for the copy of foo inlined into "croix"
64; CHECK:     DW_TAG_subprogram
65; CHECK:       DW_AT_name ("croix")
66; CHECK:       DW_TAG_formal_parameter
67; CHECK:       DW_TAG_variable
68; CHECK:       DW_TAG_inlined_subroutine
69; CHECK:     NULL
70
71; NOTE: Instructions below changed from `add` to `mul` to make them more expensive
72; and unlikely to be sunk to replace COPYs into a return value register.
73
74; Function Attrs: norecurse nounwind readnone uwtable willreturn
75define dso_local i32 @foo(i32 %bar) local_unnamed_addr !dbg !7 {
76entry:
77  call void @llvm.dbg.value(metadata i32 %bar, metadata !12, metadata !DIExpression()), !dbg !14
78  %add = mul nsw i32 %bar, 12, !dbg !15
79  call void @llvm.dbg.value(metadata i32 %add, metadata !13, metadata !DIExpression()), !dbg !14
80  ret i32 %add, !dbg !16
81}
82
83; Function Attrs: norecurse nounwind readnone uwtable willreturn
84define dso_local i32 @qux(i32 %quux) local_unnamed_addr !dbg !17 {
85entry:
86  %add.i = mul nsw i32 %quux, 12, !dbg !24
87  ret i32 %add.i, !dbg !25
88}
89
90; Function Attrs: norecurse nounwind readnone uwtable willreturn
91define dso_local i32 @croix(i32 %quux) local_unnamed_addr !dbg !26 {
92entry:
93  call void @llvm.dbg.value(metadata i32 undef, metadata !28, metadata !DIExpression()), !dbg !30
94  call void @llvm.dbg.value(metadata i32 undef, metadata !12, metadata !DIExpression()), !dbg !31
95  %add.i = mul nsw i32 %quux, 12, !dbg !33
96  call void @llvm.dbg.value(metadata i32 undef, metadata !13, metadata !DIExpression()), !dbg !31
97  call void @llvm.dbg.value(metadata i32 undef, metadata !29, metadata !DIExpression()), !dbg !30
98  ret i32 %add.i, !dbg !34
99}
100
101; Function Attrs: nofree nosync nounwind readnone speculatable willreturn
102declare void @llvm.dbg.value(metadata, metadata, metadata)
103
104!llvm.dbg.cu = !{!0}
105!llvm.module.flags = !{!3, !4, !5}
106!llvm.ident = !{!6}
107
108!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
109!1 = !DIFile(filename: "test.c", directory: ".")
110!2 = !{}
111!3 = !{i32 7, !"Dwarf Version", i32 4}
112!4 = !{i32 2, !"Debug Info Version", i32 3}
113!5 = !{i32 1, !"wchar_size", i32 4}
114!6 = !{!"clang"}
115!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 1, type: !8, scopeLine: 1, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !11)
116!8 = !DISubroutineType(types: !9)
117!9 = !{!10, !10}
118!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
119!11 = !{!12, !13}
120!12 = !DILocalVariable(name: "bar", arg: 1, scope: !7, file: !1, line: 1, type: !10)
121!13 = !DILocalVariable(name: "baz", scope: !7, file: !1, line: 2, type: !10)
122!14 = !DILocation(line: 0, scope: !7)
123!15 = !DILocation(line: 2, column: 16, scope: !7)
124!16 = !DILocation(line: 3, column: 3, scope: !7)
125!17 = distinct !DISubprogram(name: "qux", scope: !1, file: !1, line: 6, type: !8, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !18)
126!18 = !{!19, !20}
127!19 = !DILocalVariable(name: "quux", arg: 1, scope: !17, file: !1, line: 6, type: !10)
128!20 = !DILocalVariable(name: "xyzzy", scope: !17, file: !1, line: 7, type: !10)
129!21 = !DILocation(line: 0, scope: !17)
130!22 = !DILocation(line: 0, scope: !7, inlinedAt: !23)
131!23 = distinct !DILocation(line: 7, column: 15, scope: !17)
132!24 = !DILocation(line: 2, column: 16, scope: !7, inlinedAt: !23)
133!25 = !DILocation(line: 8, column: 3, scope: !17)
134!26 = distinct !DISubprogram(name: "croix", scope: !1, file: !1, line: 11, type: !8, scopeLine: 11, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !27)
135!27 = !{!28, !29}
136!28 = !DILocalVariable(name: "quux", arg: 1, scope: !26, file: !1, line: 11, type: !10)
137!29 = !DILocalVariable(name: "xyzzy", scope: !26, file: !1, line: 12, type: !10)
138!30 = !DILocation(line: 0, scope: !26)
139!31 = !DILocation(line: 0, scope: !7, inlinedAt: !32)
140!32 = distinct !DILocation(line: 12, column: 15, scope: !26)
141!33 = !DILocation(line: 2, column: 16, scope: !7, inlinedAt: !32)
142!34 = !DILocation(line: 13, column: 3, scope: !26)
143