From 294e689509fac4ce335b5abae944684b76ee7cdc Mon Sep 17 00:00:00 2001 From: Jonas Devlieghere Date: Wed, 15 Nov 2017 10:57:05 +0000 Subject: [PATCH] [DebugInfo] Fix potential CU mismatch for SubprogramScopeDIEs. In constructAbstractSubprogramScopeDIE there can be a potential mismatch between `this` and the CU of ContextDIE when a scope is shared between two DISubprograms belonging to a different CU. In that case, `this` is the CU that was specified in the IR, but the CU of ContextDIE is that of the first subprogram that was emitted. This patch fixes the mismatch by looking up the CU of ContextDIE, and switching to use that. This fixes PR35212 (https://bugs.llvm.org/show_bug.cgi?id=35212) Patch by Philip Craig! Differential revision: https://reviews.llvm.org/D39981 llvm-svn: 318289 --- .../CodeGen/AsmPrinter/DwarfCompileUnit.cpp | 20 +++++--- llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h | 5 +- llvm/test/DebugInfo/cross-cu-scope.ll | 50 +++++++++++++++++++ 3 files changed, 67 insertions(+), 8 deletions(-) create mode 100644 llvm/test/DebugInfo/cross-cu-scope.ll diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp index 603d0f7f4700b..4c7ad78e6ab42 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp @@ -638,6 +638,7 @@ void DwarfCompileUnit::constructAbstractSubprogramScopeDIE( auto *SP = cast(Scope->getScopeNode()); DIE *ContextDIE; + DwarfCompileUnit *ContextCU = this; if (includeMinimalInlineScopes()) ContextDIE = &getUnitDie(); @@ -648,18 +649,23 @@ void DwarfCompileUnit::constructAbstractSubprogramScopeDIE( else if (auto *SPDecl = SP->getDeclaration()) { ContextDIE = &getUnitDie(); getOrCreateSubprogramDIE(SPDecl); - } else + } else { ContextDIE = getOrCreateContextDIE(resolve(SP->getScope())); + // The scope may be shared with a subprogram that has already been + // constructed in another CU, in which case we need to construct this + // subprogram in the same CU. + ContextCU = DD->lookupCU(ContextDIE->getUnitDie()); + } // Passing null as the associated node because the abstract definition // shouldn't be found by lookup. - AbsDef = &createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr); - applySubprogramAttributesToDefinition(SP, *AbsDef); + AbsDef = &ContextCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr); + ContextCU->applySubprogramAttributesToDefinition(SP, *AbsDef); - if (!includeMinimalInlineScopes()) - addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); - if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, *AbsDef)) - addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer); + if (!ContextCU->includeMinimalInlineScopes()) + ContextCU->addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); + if (DIE *ObjectPointer = ContextCU->createAndAddScopeChildren(Scope, *AbsDef)) + ContextCU->addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer); } DIE *DwarfCompileUnit::constructImportedEntityDIE( diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h index 7b8cb348e48b4..2ae0b418a91ef 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h @@ -276,7 +276,7 @@ class DwarfDebug : public DebugHandlerBase { // 0, referencing the comp_dir of all the type units that use it. MCDwarfDwoLineTable SplitTypeUnitFileTable; /// @} - + /// True iff there are multiple CUs in this module. bool SingleCU; bool IsDarwin; @@ -535,6 +535,9 @@ class DwarfDebug : public DebugHandlerBase { /// going to be null. bool isLexicalScopeDIENull(LexicalScope *Scope); + /// Find the matching DwarfCompileUnit for the given CU DIE. + DwarfCompileUnit *lookupCU(const DIE *Die) { return CUDieMap.lookup(Die); } + /// \defgroup DebuggerTuning Predicates to tune DWARF for a given debugger. /// /// Returns whether we are "tuning" for a given debugger. diff --git a/llvm/test/DebugInfo/cross-cu-scope.ll b/llvm/test/DebugInfo/cross-cu-scope.ll new file mode 100644 index 0000000000000..83e82a59b28af --- /dev/null +++ b/llvm/test/DebugInfo/cross-cu-scope.ll @@ -0,0 +1,50 @@ +; RUN: %llc_dwarf %s -filetype=obj -o %t +; RUN: llvm-dwarfdump -debug-info %t | FileCheck %s + +; Reduced test case from PR35212. Two DISubprogram belong to a different CU but +; share a scope. Both are declarations and end up in the scope's CU. We want to +; check that the CU from the context DIE is used (rather than from the IR). +; This manifests itself by the DW_base_type ending up in the second CU, rather +; than in the first one as specified in the IR. + +; CHECK: DW_TAG_compile_unit +; CHECK-NEXT: discriminator 0 +; CHECK: DW_TAG_compile_unit +; CHECK-NEXT: discriminator 1 +; CHECK: DW_TAG_structure_type +; CHECK-NOT: NULL +; CHECK: DW_TAG_subprogram +; CHECK-NOT: NULL +; CHECK: DW_TAG_formal_parameter +; CHECK-NOT: NULL +; CHECK: DW_AT_type{{.*}}"usize" +; CHECK: NULL +; CHECK: DW_TAG_base_type +; CHECK-NOT: NULL +; CHECK: DW_AT_name{{.*}}"usize" + +define hidden void @foo() !dbg !4 { + ret void, !dbg !7 +} + +!llvm.dbg.cu = !{!0, !2} +!llvm.module.flags = !{!3} + +!0 = distinct !DICompileUnit(language: DW_LANG_Rust, file: !1, producer: "clang LLVM (rustc version 1.23.0-nightly (discriminator 0))", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug) +!1 = !DIFile(filename: "../lib.rs", directory: "/home/alex/code/rust4/lol") +!2 = distinct !DICompileUnit(language: DW_LANG_Rust, file: !1, producer: "clang LLVM (rustc version 1.23.0-nightly (discriminator 1))", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug) +!3 = !{i32 2, !"Debug Info Version", i32 3} +!4 = distinct !DISubprogram(name: "clone", linkageName: "_ZN5alloc3vec8{{impl}}28cloneE", scope: null, file: !1, line: 1519, type: !5, isLocal: false, isDefinition: true, scopeLine: 1519, flags: DIFlagPrototyped, isOptimized: true, unit: !0, templateParams: !6, variables: !6) +!5 = !DISubroutineType(types: !6) +!6 = !{} +!7 = !DILocation(line: 1612, scope: !8, inlinedAt: !11) +!8 = distinct !DILexicalBlock(scope: !9, file: !1, line: 86, column: 12) +!9 = distinct !DISubprogram(name: "allocate_in", linkageName: "_ZN5alloc7raw_vec8{{impl}}52allocate_inE", scope: !10, file: !1, line: 82, type: !5, isLocal: false, isDefinition: true, scopeLine: 82, flags: DIFlagPrototyped, isOptimized: true, unit: !2, templateParams: !6, variables: !6) +!10 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "RawVec", file: !1, size: 128, align: 64, elements: !6, identifier: "5c6e4db16d2c64555e40661d70c4d81e") +!11 = distinct !DILocation(line: 86, scope: !8, inlinedAt: !12) +!12 = distinct !DILocation(line: 141, scope: !13, inlinedAt: !17) +!13 = distinct !DISubprogram(name: "with_capacity", linkageName: "_ZN5alloc7raw_vec8{{impl}}36with_capacityE", scope: !10, file: !1, line: 140, type: !5, isLocal: false, isDefinition: true, scopeLine: 140, flags: DIFlagPrototyped, isOptimized: true, unit: !0, templateParams: !6, variables: !14) +!14 = !{!15} +!15 = !DILocalVariable(name: "cap", arg: 1, scope: !13, file: !1, line: 1, type: !16) +!16 = !DIBasicType(name: "usize", size: 64, encoding: DW_ATE_unsigned) +!17 = !DILocation(line: 1521, scope: !4)