From 3513dc245ec6666d20faf3a05a0f8b5e051fba0b Mon Sep 17 00:00:00 2001 From: Teresa Johnson Date: Tue, 23 Oct 2018 22:57:21 +0000 Subject: [PATCH] [ThinLTO] Fix a crash in lazy loading of Metadata Summary: This is a revised version of D41474. When the debug location is parsed in BitcodeReader::parseFunction, the scope and inlinedAt MDNodes are obtained via MDLoader->getMDNodeFwdRefOrNull(), which will create a forward ref if they were not yet loaded. Specifically, if one of these MDNodes is in the module level metadata block, and this is during ThinLTO importing, that metadata block is lazily loaded. Most places in that invoke getMDNodeFwdRefOrNull have a corresponding call to resolveForwardRefsAndPlaceholders which will take care of resolving them. E.g. places that call getMetadataFwdRefOrLoad, or at the end of parsing a function-level metadata block, or at the end of the initial lazy load of module level metadata in order to handle invocations of getMDNodeFwdRefOrNull for named metadata and global object attachments. However, the calls for the scope/inlinedAt of debug locations are not backed by any such call to resolveForwardRefsAndPlaceholders. To fix this, change the scope and inlinedAt parsing to instead use getMetadataFwdRefOrLoad, which will ensure the forward refs to lazily loaded metadata are resolved. Fixes PR35472. Reviewers: dexonsmith, Sunil_Srivastava, vsk Subscribers: inglorion, eraman, steven_wu, sebpop, mehdi_amini, dmikulin, vsk, hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D53596 llvm-svn: 345095 --- llvm/lib/Bitcode/Reader/BitcodeReader.cpp | 6 +- llvm/test/ThinLTO/X86/Inputs/pr35472.ll | 13 +++ llvm/test/ThinLTO/X86/pr35472.ll | 122 ++++++++++++++++++++++ 3 files changed, 139 insertions(+), 2 deletions(-) create mode 100644 llvm/test/ThinLTO/X86/Inputs/pr35472.ll create mode 100644 llvm/test/ThinLTO/X86/pr35472.ll diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp index aa83955e646a..1c4772968e74 100644 --- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp @@ -3520,12 +3520,14 @@ Error BitcodeReader::parseFunctionBody(Function *F) { MDNode *Scope = nullptr, *IA = nullptr; if (ScopeID) { - Scope = MDLoader->getMDNodeFwdRefOrNull(ScopeID - 1); + Scope = dyn_cast_or_null( + MDLoader->getMetadataFwdRefOrLoad(ScopeID - 1)); if (!Scope) return error("Invalid record"); } if (IAID) { - IA = MDLoader->getMDNodeFwdRefOrNull(IAID - 1); + IA = dyn_cast_or_null( + MDLoader->getMetadataFwdRefOrLoad(IAID - 1)); if (!IA) return error("Invalid record"); } diff --git a/llvm/test/ThinLTO/X86/Inputs/pr35472.ll b/llvm/test/ThinLTO/X86/Inputs/pr35472.ll new file mode 100644 index 000000000000..b9c92b3e3fbf --- /dev/null +++ b/llvm/test/ThinLTO/X86/Inputs/pr35472.ll @@ -0,0 +1,13 @@ +; ModuleID = 'b.cpp' +source_filename = "b.cpp" +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; Function Attrs: noinline optnone uwtable +define void @_Z5Alphav() { +entry: + call void @_Z5Bravov() + ret void +} + +declare void @_Z5Bravov() diff --git a/llvm/test/ThinLTO/X86/pr35472.ll b/llvm/test/ThinLTO/X86/pr35472.ll new file mode 100644 index 000000000000..9173f92063ab --- /dev/null +++ b/llvm/test/ThinLTO/X86/pr35472.ll @@ -0,0 +1,122 @@ +; Test to make sure that lazily loaded debug location scope metadata is +; handled properly. Note that we need to have the DILexicalScope !34 +; referenced from multiple function's debug locs for this to be in the +; lazily loaded module level metadata block. + +; RUN: opt -module-hash -module-summary %s -o %t1.bc +; RUN: opt -module-hash -module-summary %p/Inputs/pr35472.ll -o %t2.bc +; RUN: llvm-lto -thinlto-action=run %t1.bc %t2.bc +; RUN: llvm-nm %t1.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOa +; RUN: llvm-nm %t2.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOb + +; ThinLTOa-DAG: T _Z5Bravov +; ThinLTOa-DAG: W _ZN4EchoD2Ev +; ThinLTOb-DAG: T _Z5Alphav + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +%struct.Delta = type { %struct.Charlie } +%struct.Charlie = type { i32 } +%struct.Echo = type { %struct.Charlie } + +$_ZN4EchoD2Ev = comdat any +$_ZN5DeltaD2Ev = comdat any + +define void @_Z5Bravov() !dbg !7 { + %Hotel = alloca %struct.Delta, align 4 + %India = alloca %struct.Echo, align 4 + call void @llvm.dbg.declare(metadata %struct.Delta* %Hotel, metadata !10, metadata !DIExpression()), !dbg !22 + call void @_ZN4EchoD2Ev(%struct.Echo* %India), !dbg !28 + ret void, !dbg !28 +} + +declare void @llvm.dbg.declare(metadata, metadata, metadata) + +define linkonce_odr void @_ZN4EchoD2Ev(%struct.Echo* %this) unnamed_addr comdat align 2 { + %this.addr.i = alloca %struct.Charlie*, align 8 + call void @llvm.dbg.declare(metadata %struct.Charlie** %this.addr.i, metadata !29, metadata !DIExpression()), !dbg !32 + %this1.i = load %struct.Charlie*, %struct.Charlie** %this.addr.i, align 8 + %Golf.i = getelementptr inbounds %struct.Charlie, %struct.Charlie* %this1.i, i32 0, i32 0, !dbg !33 + ret void +} + +define linkonce_odr void @_ZN5DeltaD2Ev(%struct.Delta* %this) unnamed_addr comdat align 2 !dbg !36 { + %this.addr.i = alloca %struct.Charlie*, align 8 + call void @llvm.dbg.declare(metadata %struct.Charlie** %this.addr.i, metadata !29, metadata !DIExpression()), !dbg !41 + %this1.i = load %struct.Charlie*, %struct.Charlie** %this.addr.i, align 8 + %Golf.i = getelementptr inbounds %struct.Charlie, %struct.Charlie* %this1.i, i32 0, i32 0, !dbg !48 + ret void +} + +!llvm.module.flags = !{!3, !4, !5} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 6.0.0 (trunk 321056)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "a.cpp", directory: "/home/sunil/185335/302") +!2 = !{} +!3 = !{i32 2, !"Dwarf Version", i32 4} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = !{i32 1, !"wchar_size", i32 4} +!7 = distinct !DISubprogram(name: "Bravo", linkageName: "_Z5Bravov", scope: !1, file: !1, line: 17, type: !8, isLocal: false, isDefinition: true, scopeLine: 17, flags: DIFlagPrototyped, isOptimized: false, unit: !0) +!8 = !DISubroutineType(types: !9) +!9 = !{null} +!10 = !DILocalVariable(name: "Hotel", scope: !7, file: !1, line: 18, type: !11) +!11 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "Delta", file: !1, line: 6, size: 32, elements: !12, identifier: "_ZTS5Delta") +!12 = !{!13} +!13 = !DIDerivedType(tag: DW_TAG_member, name: "Foxtrot", scope: !11, file: !1, line: 7, baseType: !14, size: 32) +!14 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "Charlie", file: !1, line: 1, size: 32, elements: !15, identifier: "_ZTS7Charlie") +!15 = !{!16, !18} +!16 = !DIDerivedType(tag: DW_TAG_member, name: "Golf", scope: !14, file: !1, line: 3, baseType: !17, size: 32) +!17 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!18 = !DISubprogram(name: "~Charlie", scope: !14, file: !1, line: 2, type: !19, isLocal: false, isDefinition: false, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: false) +!19 = !DISubroutineType(types: !20) +!20 = !{null, !21} +!21 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !14, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!22 = !DILocation(line: 18, column: 11, scope: !7) +!24 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "Echo", file: !1, line: 10, size: 32, elements: !25, identifier: "_ZTS4Echo") +!25 = !{!26} +!26 = !DIDerivedType(tag: DW_TAG_member, name: "Foxtrot", scope: !24, file: !1, line: 11, baseType: !14, size: 32) +!28 = !DILocation(line: 20, column: 1, scope: !7) +!29 = !DILocalVariable(name: "this", arg: 1, scope: !30, type: !31, flags: DIFlagArtificial | DIFlagObjectPointer) +!30 = distinct !DISubprogram(name: "~Charlie", linkageName: "_ZN7CharlieD2Ev", scope: !14, file: !1, line: 2, type: !19, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !18) +!31 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !14, size: 64) +!32 = !DILocation(line: 0, scope: !30) +!33 = !DILocation(line: 2, column: 53, scope: !34) +!34 = distinct !DILexicalBlock(scope: !30, file: !1, line: 2, column: 51) +!36 = distinct !DISubprogram(name: "~Delta", linkageName: "_ZN5DeltaD2Ev", scope: !11, file: !1, line: 6, type: !37, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagArtificial | DIFlagPrototyped, isOptimized: false, unit: !0, declaration: !40) +!37 = !DISubroutineType(types: !38) +!38 = !{null, !39} +!39 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!40 = !DISubprogram(name: "~Delta", scope: !11, type: !37, isLocal: false, isDefinition: false, flags: DIFlagArtificial | DIFlagPrototyped, isOptimized: false) +!41 = !DILocation(line: 0, scope: !30, inlinedAt: !42) +!42 = distinct !DILocation(line: 6, column: 8, scope: !43) +!43 = distinct !DILexicalBlock(scope: !36, file: !1, line: 6, column: 8) +!48 = !DILocation(line: 2, column: 53, scope: !34, inlinedAt: !42) + +;---------------------------------------------------------------------------------------------- +; Compiled from following two source files with 'clang++ -S --std=c++11 -O0 -g -flto=thin' +; struct Charlie { +; __attribute__((__always_inline__)) ~Charlie() { Golf = 0; } +; int Golf; +; }; +; +; struct Delta { +; Charlie Foxtrot; +; }; +; +; struct Echo { +; Charlie Foxtrot; +; __attribute__((nodebug)) ~Echo() = default; +; }; +; +; extern void Bravo(); +; +; void Bravo() { +; Delta Hotel; +; Echo India; +; } +; ----------------------------- +; extern void Bravo(); +; extern void Alpha(); +; void Alpha() { Bravo(); } +