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| ; REQUIRES: object-emission
; RUN: %llc_dwarf -O2 -filetype=obj < %s | llvm-dwarfdump -v -debug-info - | FileCheck %s
; This is a test case that's as reduced as I can get it, though I haven't fully
; understood the mechanisms by which this bug occurs, so perhaps there's further
; simplification to be had (it's certainly a bit non-obvious what's going on). I
; hesitate to hand-craft or otherwise simplify the IR compared to what Clang
; generates as this is a particular tickling of optimizations and debug location
; propagation I want a realistic example of.
; Generated with clang-tot -cc1 -g -O2 -w -std=c++11 -fsanitize=address,use-after-return -fcxx-exceptions -fexceptions -x c++ incorrect-variable-debug-loc.cpp -emit-llvm
; struct A {
; int m_fn1();
; };
;
; struct B {
; void __attribute__((always_inline)) m_fn2() { i = 0; }
; int i;
; };
;
; struct C {
; void m_fn3();
; int j;
; B b;
; };
;
; int fn1() {
; C A;
; A.b.m_fn2();
; A.m_fn3();
; }
; void C::m_fn3() {
; A().m_fn1();
; b.m_fn2();
; }
; CHECK: DW_TAG_structure_type
; CHECK-NEXT: DW_AT_name {{.*}} "C"
; CHECK: [[M_FN3_DECL:.*]]: DW_TAG_subprogram
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: DW_AT_name {{.*}} "m_fn3"
; CHECK: DW_AT_specification {{.*}} {[[M_FN3_DECL]]}
; CHECK-NOT: DW_TAG
; CHECK: DW_TAG_formal_parameter
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "this"
%struct.C = type { i32, %struct.B }
%struct.B = type { i32 }
%struct.A = type { i8 }
@llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 1, void ()* @asan.module_ctor, i8* null }]
@__asan_option_detect_stack_use_after_return = external global i32
@___asan_gen_ = private unnamed_addr constant [11 x i8] c"1 32 8 1 A\00", align 1
@___asan_gen_1 = private unnamed_addr constant [13 x i8] c"1 32 1 3 tmp\00", align 1
; Function Attrs: noreturn sanitize_address
define i32 @_Z3fn1v() #0 !dbg !22 {
entry:
%MyAlloca = alloca [64 x i8], align 32, !dbg !39
%0 = ptrtoint [64 x i8]* %MyAlloca to i64, !dbg !39
%1 = load i32, i32* @__asan_option_detect_stack_use_after_return, !dbg !39
%2 = icmp ne i32 %1, 0, !dbg !39
br i1 %2, label %3, label %5
; <label>:3 ; preds = %entry
%4 = call i64 @__asan_stack_malloc_0(i64 64, i64 %0), !dbg !39
br label %5
; <label>:5 ; preds = %entry, %3
%6 = phi i64 [ %0, %entry ], [ %4, %3 ], !dbg !39
%7 = add i64 %6, 32, !dbg !39
%8 = inttoptr i64 %7 to %struct.C*, !dbg !39
%9 = inttoptr i64 %6 to i64*, !dbg !39
store i64 1102416563, i64* %9, !dbg !39
%10 = add i64 %6, 8, !dbg !39
%11 = inttoptr i64 %10 to i64*, !dbg !39
store i64 ptrtoint ([11 x i8]* @___asan_gen_ to i64), i64* %11, !dbg !39
%12 = add i64 %6, 16, !dbg !39
%13 = inttoptr i64 %12 to i64*, !dbg !39
store i64 ptrtoint (i32 ()* @_Z3fn1v to i64), i64* %13, !dbg !39
%14 = lshr i64 %6, 3, !dbg !39
%15 = add i64 %14, 2147450880, !dbg !39
%16 = add i64 %15, 0, !dbg !39
%17 = inttoptr i64 %16 to i64*, !dbg !39
store i64 -868083117767659023, i64* %17, !dbg !39
%i.i = getelementptr inbounds %struct.C, %struct.C* %8, i64 0, i32 1, i32 0, !dbg !39
%18 = ptrtoint i32* %i.i to i64, !dbg !39
%19 = lshr i64 %18, 3, !dbg !39
%20 = add i64 %19, 2147450880, !dbg !39
%21 = inttoptr i64 %20 to i8*, !dbg !39
%22 = load i8, i8* %21, !dbg !39
%23 = icmp ne i8 %22, 0, !dbg !39
br i1 %23, label %24, label %30, !dbg !39
; <label>:24 ; preds = %5
%25 = and i64 %18, 7, !dbg !39
%26 = add i64 %25, 3, !dbg !39
%27 = trunc i64 %26 to i8, !dbg !39
%28 = icmp sge i8 %27, %22, !dbg !39
br i1 %28, label %29, label %30
; <label>:29 ; preds = %24
call void @__asan_report_store4(i64 %18), !dbg !39
call void asm sideeffect "", ""()
unreachable
; <label>:30 ; preds = %24, %5
store i32 0, i32* %i.i, align 4, !dbg !39, !tbaa !41
tail call void @llvm.dbg.value(metadata %struct.C* %8, metadata !27, metadata !DIExpression(DW_OP_deref)), !dbg !46
call void @_ZN1C5m_fn3Ev(%struct.C* %8), !dbg !47
unreachable, !dbg !47
}
; Function Attrs: sanitize_address
define void @_ZN1C5m_fn3Ev(%struct.C* nocapture %this) #1 align 2 !dbg !28 {
entry:
%MyAlloca = alloca [64 x i8], align 32, !dbg !48
%0 = ptrtoint [64 x i8]* %MyAlloca to i64, !dbg !48
%1 = load i32, i32* @__asan_option_detect_stack_use_after_return, !dbg !48
%2 = icmp ne i32 %1, 0, !dbg !48
br i1 %2, label %3, label %5
; <label>:3 ; preds = %entry
%4 = call i64 @__asan_stack_malloc_0(i64 64, i64 %0), !dbg !48
br label %5
; <label>:5 ; preds = %entry, %3
%6 = phi i64 [ %0, %entry ], [ %4, %3 ], !dbg !48
%7 = add i64 %6, 32, !dbg !48
%8 = inttoptr i64 %7 to %struct.A*, !dbg !48
%9 = inttoptr i64 %6 to i64*, !dbg !48
store i64 1102416563, i64* %9, !dbg !48
%10 = add i64 %6, 8, !dbg !48
%11 = inttoptr i64 %10 to i64*, !dbg !48
store i64 ptrtoint ([13 x i8]* @___asan_gen_1 to i64), i64* %11, !dbg !48
%12 = add i64 %6, 16, !dbg !48
%13 = inttoptr i64 %12 to i64*, !dbg !48
store i64 ptrtoint (void (%struct.C*)* @_ZN1C5m_fn3Ev to i64), i64* %13, !dbg !48
%14 = lshr i64 %6, 3, !dbg !48
%15 = add i64 %14, 2147450880, !dbg !48
%16 = add i64 %15, 0, !dbg !48
%17 = inttoptr i64 %16 to i64*, !dbg !48
store i64 -868083113472691727, i64* %17, !dbg !48
tail call void @llvm.dbg.value(metadata %struct.C* %this, metadata !30, metadata !DIExpression()), !dbg !48
%call = call i32 @_ZN1A5m_fn1Ev(%struct.A* %8), !dbg !49
%i.i = getelementptr inbounds %struct.C, %struct.C* %this, i64 0, i32 1, i32 0, !dbg !50
%18 = ptrtoint i32* %i.i to i64, !dbg !50
%19 = lshr i64 %18, 3, !dbg !50
%20 = add i64 %19, 2147450880, !dbg !50
%21 = inttoptr i64 %20 to i8*, !dbg !50
%22 = load i8, i8* %21, !dbg !50
%23 = icmp ne i8 %22, 0, !dbg !50
br i1 %23, label %24, label %30, !dbg !50
; <label>:24 ; preds = %5
%25 = and i64 %18, 7, !dbg !50
%26 = add i64 %25, 3, !dbg !50
%27 = trunc i64 %26 to i8, !dbg !50
%28 = icmp sge i8 %27, %22, !dbg !50
br i1 %28, label %29, label %30
; <label>:29 ; preds = %24
call void @__asan_report_store4(i64 %18), !dbg !50
call void asm sideeffect "", ""()
unreachable
; <label>:30 ; preds = %24, %5
store i32 0, i32* %i.i, align 4, !dbg !50, !tbaa !41
store i64 1172321806, i64* %9, !dbg !52
%31 = icmp ne i64 %6, %0, !dbg !52
br i1 %31, label %32, label %39, !dbg !52
; <label>:32 ; preds = %30
%33 = add i64 %15, 0, !dbg !52
%34 = inttoptr i64 %33 to i64*, !dbg !52
store i64 -723401728380766731, i64* %34, !dbg !52
%35 = add i64 %6, 56, !dbg !52
%36 = inttoptr i64 %35 to i64*, !dbg !52
%37 = load i64, i64* %36, !dbg !52
%38 = inttoptr i64 %37 to i8*, !dbg !52
store i8 0, i8* %38, !dbg !52
br label %42, !dbg !52
; <label>:39 ; preds = %30
%40 = add i64 %15, 0, !dbg !52
%41 = inttoptr i64 %40 to i64*, !dbg !52
store i64 0, i64* %41, !dbg !52
br label %42, !dbg !52
; <label>:42 ; preds = %39, %32
ret void, !dbg !52
}
declare i32 @_ZN1A5m_fn1Ev(%struct.A*) #2
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, metadata, metadata) #3
define internal void @asan.module_ctor() {
tail call void @__asan_init_v3()
ret void
}
declare void @__asan_init_v3()
declare void @__asan_report_load1(i64)
declare void @__asan_load1(i64)
declare void @__asan_report_load2(i64)
declare void @__asan_load2(i64)
declare void @__asan_report_load4(i64)
declare void @__asan_load4(i64)
declare void @__asan_report_load8(i64)
declare void @__asan_load8(i64)
declare void @__asan_report_load16(i64)
declare void @__asan_load16(i64)
declare void @__asan_report_store1(i64)
declare void @__asan_store1(i64)
declare void @__asan_report_store2(i64)
declare void @__asan_store2(i64)
declare void @__asan_report_store4(i64)
declare void @__asan_store4(i64)
declare void @__asan_report_store8(i64)
declare void @__asan_store8(i64)
declare void @__asan_report_store16(i64)
declare void @__asan_store16(i64)
declare void @__asan_report_load_n(i64, i64)
declare void @__asan_report_store_n(i64, i64)
declare void @__asan_loadN(i64, i64)
declare void @__asan_storeN(i64, i64)
declare i8* @__asan_memmove(i8*, i8*, i64)
declare i8* @__asan_memcpy(i8*, i8*, i64)
declare i8* @__asan_memset(i8*, i32, i64)
declare void @__asan_handle_no_return()
declare void @__sanitizer_cov()
declare void @__sanitizer_ptr_cmp(i64, i64)
declare void @__sanitizer_ptr_sub(i64, i64)
declare i64 @__asan_stack_malloc_0(i64, i64)
declare void @__asan_stack_free_0(i64, i64, i64)
declare i64 @__asan_stack_malloc_1(i64, i64)
declare void @__asan_stack_free_1(i64, i64, i64)
declare i64 @__asan_stack_malloc_2(i64, i64)
declare void @__asan_stack_free_2(i64, i64, i64)
declare i64 @__asan_stack_malloc_3(i64, i64)
declare void @__asan_stack_free_3(i64, i64, i64)
declare i64 @__asan_stack_malloc_4(i64, i64)
declare void @__asan_stack_free_4(i64, i64, i64)
declare i64 @__asan_stack_malloc_5(i64, i64)
declare void @__asan_stack_free_5(i64, i64, i64)
declare i64 @__asan_stack_malloc_6(i64, i64)
declare void @__asan_stack_free_6(i64, i64, i64)
declare i64 @__asan_stack_malloc_7(i64, i64)
declare void @__asan_stack_free_7(i64, i64, i64)
declare i64 @__asan_stack_malloc_8(i64, i64)
declare void @__asan_stack_free_8(i64, i64, i64)
declare i64 @__asan_stack_malloc_9(i64, i64)
declare void @__asan_stack_free_9(i64, i64, i64)
declare i64 @__asan_stack_malloc_10(i64, i64)
declare void @__asan_stack_free_10(i64, i64, i64)
declare void @__asan_poison_stack_memory(i64, i64)
declare void @__asan_unpoison_stack_memory(i64, i64)
declare void @__asan_before_dynamic_init(i64)
declare void @__asan_after_dynamic_init()
declare void @__asan_register_globals(i64, i64)
declare void @__asan_unregister_globals(i64, i64)
declare void @__sanitizer_cov_module_init(i64)
attributes #0 = { noreturn sanitize_address "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" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { sanitize_address "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" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { "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" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #3 = { nounwind readnone }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!36, !37}
!llvm.ident = !{!38}
!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)
!1 = !DIFile(filename: "<stdin>", directory: "/tmp/dbginfo")
!2 = !{}
!3 = !{!4, !14}
!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "C", line: 10, size: 64, align: 32, file: !5, elements: !6, identifier: "_ZTS1C")
!5 = !DIFile(filename: "incorrect-variable-debug-loc.cpp", directory: "/tmp/dbginfo")
!6 = !{!7, !9, !10}
!7 = !DIDerivedType(tag: DW_TAG_member, name: "j", line: 12, size: 32, align: 32, file: !5, scope: !4, baseType: !8)
!8 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!9 = !DIDerivedType(tag: DW_TAG_member, name: "b", line: 13, size: 32, align: 32, offset: 32, file: !5, scope: !4, baseType: !14)
!10 = !DISubprogram(name: "m_fn3", linkageName: "_ZN1C5m_fn3Ev", line: 11, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 11, file: !5, scope: !4, type: !11)
!11 = !DISubroutineType(types: !12)
!12 = !{null, !13}
!13 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer, baseType: !4)
!14 = !DICompositeType(tag: DW_TAG_structure_type, name: "B", line: 5, size: 32, align: 32, file: !5, elements: !15, identifier: "_ZTS1B")
!15 = !{!16, !17}
!16 = !DIDerivedType(tag: DW_TAG_member, name: "i", line: 7, size: 32, align: 32, file: !5, scope: !14, baseType: !8)
!17 = !DISubprogram(name: "m_fn2", linkageName: "_ZN1B5m_fn2Ev", line: 6, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 6, file: !5, scope: !14, type: !18)
!18 = !DISubroutineType(types: !19)
!19 = !{null, !20}
!20 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer, baseType: !14)
!22 = distinct !DISubprogram(name: "fn1", linkageName: "_Z3fn1v", line: 16, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !0, scopeLine: 16, file: !5, scope: !23, type: !24, retainedNodes: !26)
!23 = !DIFile(filename: "incorrect-variable-debug-loc.cpp", directory: "/tmp/dbginfo")
!24 = !DISubroutineType(types: !25)
!25 = !{!8}
!26 = !{!27}
!27 = !DILocalVariable(name: "A", line: 17, scope: !22, file: !23, type: !4)
!28 = distinct !DISubprogram(name: "m_fn3", linkageName: "_ZN1C5m_fn3Ev", line: 21, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !0, scopeLine: 21, file: !5, scope: !4, type: !11, declaration: !10, retainedNodes: !29)
!29 = !{!30}
!30 = !DILocalVariable(name: "this", arg: 1, flags: DIFlagArtificial | DIFlagObjectPointer, scope: !28, type: !31)
!31 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !4)
!32 = distinct !DISubprogram(name: "m_fn2", linkageName: "_ZN1B5m_fn2Ev", line: 6, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !0, scopeLine: 6, file: !5, scope: !14, type: !18, declaration: !17, retainedNodes: !33)
!33 = !{!34}
!34 = !DILocalVariable(name: "this", arg: 1, flags: DIFlagArtificial | DIFlagObjectPointer, scope: !32, type: !35)
!35 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !14)
!36 = !{i32 2, !"Dwarf Version", i32 4}
!37 = !{i32 2, !"Debug Info Version", i32 3}
!38 = !{!"clang version 3.5.0 "}
!39 = !DILocation(line: 6, scope: !32, inlinedAt: !40)
!40 = !DILocation(line: 18, scope: !22)
!41 = !{!42, !43, i64 0}
!42 = !{!"struct", !43, i64 0}
!43 = !{!"int", !44, i64 0}
!44 = !{!"omnipotent char", !45, i64 0}
!45 = !{!"Simple C/C++ TBAA"}
!46 = !DILocation(line: 17, scope: !22)
!47 = !DILocation(line: 19, scope: !22)
!48 = !DILocation(line: 0, scope: !28)
!49 = !DILocation(line: 22, scope: !28)
!50 = !DILocation(line: 6, scope: !32, inlinedAt: !51)
!51 = !DILocation(line: 23, scope: !28)
!52 = !DILocation(line: 24, scope: !28)
|