1; REQUIRES: object-emission 2 3; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s 4 5; Built from the following source with clang -O1 6; struct S { int i; }; 7; int function(struct S s, int i) { return s.i + i; } 8 9; Due to the X86_64 ABI, 's' is passed in registers and once optimized, the 10; entirety of 's' is never reconstituted, since only the int is required, and 11; thus the variable's location is unknown/dead to debug info. 12 13; Future/current work should enable us to describe partial variables, which, in 14; this case, happens to be the entire variable. 15 16; CHECK: DW_TAG_subprogram 17; CHECK-NOT: DW_TAG 18; CHECK: DW_AT_name {{.*}} "function" 19; CHECK-NOT: {{DW_TAG|NULL}} 20; CHECK: DW_TAG_formal_parameter 21; CHECK-NOT: DW_TAG 22; CHECK: DW_AT_name {{.*}} "s" 23; CHECK-NOT: DW_TAG 24; FIXME: Even though 's' is never reconstituted into a struct, the one member 25; variable is still live and used, and so we should be able to describe 's's 26; location as the location of that int. 27; CHECK-NOT: DW_AT_location 28; CHECK-NOT: {{DW_TAG|NULL}} 29; CHECK: DW_TAG_formal_parameter 30; CHECK-NOT: DW_TAG 31; CHECK: DW_AT_location 32; CHECK-NOT: DW_TAG 33; CHECK: DW_AT_name {{.*}} "i" 34 35 36%struct.S = type { i32 } 37 38; Function Attrs: nounwind readnone uwtable 39define i32 @_Z8function1Si(i32 %s.coerce, i32 %i) #0 !dbg !9 { 40entry: 41 tail call void @llvm.dbg.declare(metadata %struct.S* undef, metadata !14, metadata !DIExpression()), !dbg !20 42 tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !15, metadata !DIExpression()), !dbg !20 43 %add = add nsw i32 %i, %s.coerce, !dbg !20 44 ret i32 %add, !dbg !20 45} 46 47; Function Attrs: nounwind readnone 48declare void @llvm.dbg.declare(metadata, metadata, metadata) #1 49 50; Function Attrs: nounwind readnone 51declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1 52 53attributes #0 = { nounwind readnone uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } 54attributes #1 = { nounwind readnone } 55 56!llvm.dbg.cu = !{!0} 57!llvm.module.flags = !{!16, !17} 58!llvm.ident = !{!18} 59 60!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.5.0 ", isOptimized: true, emissionKind: FullDebug, file: !1, enums: !2, retainedTypes: !3, globals: !2, imports: !2) 61!1 = !DIFile(filename: "dead-argument-order.cpp", directory: "/tmp/dbginfo") 62!2 = !{} 63!3 = !{!4} 64!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "S", line: 1, size: 32, align: 32, file: !1, elements: !5, identifier: "_ZTS1S") 65!5 = !{!6} 66!6 = !DIDerivedType(tag: DW_TAG_member, name: "i", line: 1, size: 32, align: 32, file: !1, scope: !4, baseType: !7) 67!7 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed) 68!9 = distinct !DISubprogram(name: "function", linkageName: "_Z8function1Si", line: 2, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !0, scopeLine: 2, file: !1, scope: !10, type: !11, variables: !13) 69!10 = !DIFile(filename: "dead-argument-order.cpp", directory: "/tmp/dbginfo") 70!11 = !DISubroutineType(types: !12) 71!12 = !{!7, !4, !7} 72!13 = !{!14, !15} 73!14 = !DILocalVariable(name: "s", line: 2, arg: 1, scope: !9, file: !10, type: !4) 74!15 = !DILocalVariable(name: "i", line: 2, arg: 2, scope: !9, file: !10, type: !7) 75!16 = !{i32 2, !"Dwarf Version", i32 4} 76!17 = !{i32 2, !"Debug Info Version", i32 3} 77!18 = !{!"clang version 3.5.0 "} 78!19 = !{%struct.S* undef} 79!20 = !DILocation(line: 2, scope: !9) 80 81