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1; RUN: opt -mem2reg %s -S -o - | FileCheck %s
2
3;; Check that mem2reg removes dbg.value(%local, DIExpression(DW_OP_deref...))
4;; that instcombine LowerDbgDeclare inserted before the call to 'esc' when
5;; promoting the alloca %local after 'esc' has been inlined. Without this we
6;; provide no location for 'local', even though it is provably constant
7;; throughout after inlining.
8;;
9;; $ clang reduce.c -O2 -g -emit-llvm -S -o tmp.ll -Xclang -disable-llvm-passes
10;; $ opt tmp.ll -o - -instcombine -inline -S
11;; $ cat reduce.c
12;; long a;
13;; int b;
14;; void c();
15;; __attribute__((__always_inline__))
16;; static void esc(long *e) {
17;;   *e = a;
18;;   c();
19;;   if (b)
20;;     *e = 0;
21;; }
22;;
23;; void fun() {
24;;   long local = 0;
25;;   esc(&local);
26;; }
27
28; CHECK: define dso_local void @fun()
29; CHECK-NEXT: entry:
30; CHECK-NEXT: call void @llvm.dbg.value(metadata i64 0, metadata ![[LOCAL:[0-9]+]], metadata !DIExpression())
31; CHECK-NOT: call void @llvm.dbg.value({{.*}}, metadata ![[LOCAL]]
32; CHECK: ![[LOCAL]] = !DILocalVariable(name: "local",
33
34@a = dso_local global i64 0, align 8, !dbg !0
35@b = dso_local global i32 0, align 4, !dbg !6
36
37define dso_local void @fun() !dbg !14 {
38entry:
39  %e.addr.i = alloca i64*, align 8
40  %local = alloca i64, align 8
41  %0 = bitcast i64* %local to i8*, !dbg !19
42  call void @llvm.lifetime.start.p0i8(i64 8, i8* nonnull %0), !dbg !19
43  call void @llvm.dbg.value(metadata i64 0, metadata !18, metadata !DIExpression()), !dbg !20
44  store i64 0, i64* %local, align 8, !dbg !21
45  call void @llvm.dbg.value(metadata i64* %local, metadata !18, metadata !DIExpression(DW_OP_deref)), !dbg !20
46  %1 = bitcast i64** %e.addr.i to i8*, !dbg !26
47  call void @llvm.lifetime.start.p0i8(i64 8, i8* %1), !dbg !26
48  call void @llvm.dbg.value(metadata i64* %local, metadata !32, metadata !DIExpression()), !dbg !26
49  store i64* %local, i64** %e.addr.i, align 8
50  %2 = load i64, i64* @a, align 8, !dbg !36
51  call void @llvm.dbg.value(metadata i64* %local, metadata !32, metadata !DIExpression()), !dbg !26
52  store i64 %2, i64* %local, align 8, !dbg !37
53  call void (...) @c(), !dbg !38
54  %3 = load i32, i32* @b, align 4, !dbg !39
55  %tobool.not.i = icmp eq i32 %3, 0, !dbg !39
56  br i1 %tobool.not.i, label %esc.exit, label %if.then.i, !dbg !43
57
58if.then.i:                                        ; preds = %entry
59  %4 = load i64*, i64** %e.addr.i, align 8, !dbg !44
60  call void @llvm.dbg.value(metadata i64* %4, metadata !32, metadata !DIExpression()), !dbg !26
61  store i64 0, i64* %4, align 8, !dbg !45
62  br label %esc.exit, !dbg !46
63
64esc.exit:                                         ; preds = %entry, %if.then.i
65  %5 = bitcast i64** %e.addr.i to i8*, !dbg !47
66  call void @llvm.lifetime.end.p0i8(i64 8, i8* %5), !dbg !47
67  %6 = bitcast i64* %local to i8*, !dbg !48
68  call void @llvm.lifetime.end.p0i8(i64 8, i8* nonnull %6), !dbg !48
69  ret void, !dbg !48
70}
71
72declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture)
73declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
74declare void @llvm.dbg.value(metadata, metadata, metadata)
75declare !dbg !49 dso_local void @c(...)
76
77!llvm.dbg.cu = !{!2}
78!llvm.module.flags = !{!10, !11, !12}
79!llvm.ident = !{!13}
80
81!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
82!1 = distinct !DIGlobalVariable(name: "a", scope: !2, file: !3, line: 1, type: !9, isLocal: false, isDefinition: true)
83!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 12.0.0)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, splitDebugInlining: false, nameTableKind: None)
84!3 = !DIFile(filename: "reduce.c", directory: "/")
85!4 = !{}
86!5 = !{!0, !6}
87!6 = !DIGlobalVariableExpression(var: !7, expr: !DIExpression())
88!7 = distinct !DIGlobalVariable(name: "b", scope: !2, file: !3, line: 2, type: !8, isLocal: false, isDefinition: true)
89!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
90!9 = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
91!10 = !{i32 7, !"Dwarf Version", i32 4}
92!11 = !{i32 2, !"Debug Info Version", i32 3}
93!12 = !{i32 1, !"wchar_size", i32 4}
94!13 = !{!"clang version 12.0.0"}
95!14 = distinct !DISubprogram(name: "fun", scope: !3, file: !3, line: 12, type: !15, scopeLine: 12, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !17)
96!15 = !DISubroutineType(types: !16)
97!16 = !{null}
98!17 = !{!18}
99!18 = !DILocalVariable(name: "local", scope: !14, file: !3, line: 13, type: !9)
100!19 = !DILocation(line: 13, column: 3, scope: !14)
101!20 = !DILocation(line: 0, scope: !14)
102!21 = !DILocation(line: 13, column: 8, scope: !14)
103!26 = !DILocation(line: 0, scope: !27, inlinedAt: !33)
104!27 = distinct !DISubprogram(name: "esc", scope: !3, file: !3, line: 5, type: !28, scopeLine: 5, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !31)
105!28 = !DISubroutineType(types: !29)
106!29 = !{null, !30}
107!30 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64)
108!31 = !{!32}
109!32 = !DILocalVariable(name: "e", arg: 1, scope: !27, file: !3, line: 5, type: !30)
110!33 = distinct !DILocation(line: 14, column: 3, scope: !14)
111!36 = !DILocation(line: 6, column: 8, scope: !27, inlinedAt: !33)
112!37 = !DILocation(line: 6, column: 6, scope: !27, inlinedAt: !33)
113!38 = !DILocation(line: 7, column: 3, scope: !27, inlinedAt: !33)
114!39 = !DILocation(line: 8, column: 7, scope: !40, inlinedAt: !33)
115!40 = distinct !DILexicalBlock(scope: !27, file: !3, line: 8, column: 7)
116!43 = !DILocation(line: 8, column: 7, scope: !27, inlinedAt: !33)
117!44 = !DILocation(line: 9, column: 6, scope: !40, inlinedAt: !33)
118!45 = !DILocation(line: 9, column: 8, scope: !40, inlinedAt: !33)
119!46 = !DILocation(line: 9, column: 5, scope: !40, inlinedAt: !33)
120!47 = !DILocation(line: 10, column: 1, scope: !27, inlinedAt: !33)
121!48 = !DILocation(line: 15, column: 1, scope: !14)
122!49 = !DISubprogram(name: "c", scope: !3, file: !3, line: 3, type: !50, spFlags: DISPFlagOptimized, retainedNodes: !4)
123!50 = !DISubroutineType(types: !51)
124!51 = !{null, null}
125