1; RUN: llc -mtriple=x86_64-apple-macosx <%s | FileCheck %s
2; Test that we don't generate empty .debug_loc entries.  Originally, there were
3; two empty .debug_loc entries for 'a' in an otherwise empty .debug_loc list.
4;
5; CHECK:      .section __DWARF,__debug_loc,regular,debug
6; CHECK-NEXT: Lsection_debug_loc:
7; CHECK-NEXT: .section __DWARF,__debug_abbrev,regular,debug
8;
9; Test that the variable stuck around.
10; CHECK:      .section __DWARF,__debug_info,regular,debug
11; CHECK:      DW_TAG_variable
12; CHECK-NOT:  DW_AT_location
13
14; Generated using clang -cc1 with the following args:
15;
16;   -triple x86_64-apple-macosx -emit-llvm -gdwarf-4 -O1
17;
18; From this testcase:
19;
20;;   void fn1() {
21;;     float a = 1;
22;;     for (;;)
23;;       a = 0;
24;;   }
25
26; Function Attrs: noreturn nounwind readnone
27define void @_Z3fn1v() #0 !dbg !4 {
28entry:
29  tail call void @llvm.dbg.value(metadata float 1.000000e+00, i64 0, metadata !9, metadata !14), !dbg !15
30  br label %for.cond, !dbg !16
31
32for.cond:                                         ; preds = %for.cond, %entry
33  tail call void @llvm.dbg.value(metadata float 0.000000e+00, i64 0, metadata !9, metadata !14), !dbg !15
34  br label %for.cond, !dbg !17
35}
36
37; Function Attrs: nounwind readnone
38declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1
39
40attributes #0 = { noreturn nounwind readnone "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
41attributes #1 = { nounwind readnone }
42
43!llvm.dbg.cu = !{!0}
44!llvm.module.flags = !{!11, !12}
45!llvm.ident = !{!13}
46
47!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.7.0 (trunk 238517) (llvm/trunk 238524)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2)
48!1 = !DIFile(filename: "<stdin>", directory: "/Users/dexonsmith/data/llvm/bootstrap/play/delta2/testcase")
49!2 = !{}
50!3 = !{!4}
51!4 = distinct !DISubprogram(name: "fn1", linkageName: "_Z3fn1v", scope: !5, file: !5, line: 1, type: !6, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: true, variables: !8)
52!5 = !DIFile(filename: "t.cpp", directory: "/Users/dexonsmith/data/llvm/bootstrap/play/delta2/testcase")
53!6 = !DISubroutineType(types: !7)
54!7 = !{null}
55!8 = !{!9}
56!9 = !DILocalVariable(name: "a", scope: !4, file: !5, line: 2, type: !10)
57!10 = !DIBasicType(name: "float", size: 32, align: 32, encoding: DW_ATE_float)
58!11 = !{i32 2, !"Dwarf Version", i32 4}
59!12 = !{i32 2, !"Debug Info Version", i32 3}
60!13 = !{!"clang version 3.7.0 (trunk 238517) (llvm/trunk 238524)"}
61!14 = !DIExpression()
62!15 = !DILocation(line: 2, scope: !4)
63!16 = !DILocation(line: 3, scope: !4)
64!17 = !DILocation(line: 3, scope: !18)
65!18 = distinct !DILexicalBlock(scope: !19, file: !5, line: 3)
66!19 = distinct !DILexicalBlock(scope: !4, file: !5, line: 3)
67