X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FAsmPrinter%2FDwarfDebug.cpp;h=b45d5917615eb60ddebcda023b8e653f53218e2e;hb=fcfd56262b1cc06518f2323de541e4de99e93e46;hp=8de084abff1e9ad51624fdae6587d6ad009d9b89;hpb=b861d48f798bc772be99df66d40727c80d3da1dd;p=oota-llvm.git diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 8de084abff1..b45d5917615 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -36,6 +36,7 @@ #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/Dwarf.h" +#include "llvm/Support/Endian.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/FormattedStream.h" #include "llvm/Support/LEB128.h" @@ -98,10 +99,6 @@ DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden, clEnumVal(Disable, "Disabled"), clEnumValEnd), cl::init(Default)); -static cl::opt -DwarfVersionNumber("dwarf-version", cl::Hidden, - cl::desc("Generate DWARF for dwarf version."), cl::init(0)); - static const char *const DWARFGroupName = "DWARF Emission"; static const char *const DbgTimerName = "DWARF Debug Writer"; @@ -209,9 +206,12 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) else HasDwarfPubSections = DwarfPubSections == Enable; + unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion; DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber : MMI->getModule()->getDwarfVersion(); + Asm->OutStreamer.getContext().setDwarfVersion(DwarfVersion); + { NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); beginModule(); @@ -314,43 +314,7 @@ bool DwarfDebug::isSubprogramContext(const MDNode *Context) { // scope then create and insert DIEs for these variables. DIE &DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit &SPCU, DISubprogram SP) { - DIE *SPDie = SPCU.getDIE(SP); - - assert(SPDie && "Unable to find subprogram DIE!"); - - // If we're updating an abstract DIE, then we will be adding the children and - // object pointer later on. But what we don't want to do is process the - // concrete DIE twice. - if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) { - // Pick up abstract subprogram DIE. - SPDie = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, SPCU.getUnitDie()); - SPCU.addDIEEntry(*SPDie, dwarf::DW_AT_abstract_origin, *AbsSPDIE); - } else { - DISubprogram SPDecl = SP.getFunctionDeclaration(); - if (!SPDecl.isSubprogram()) { - // There is not any need to generate specification DIE for a function - // defined at compile unit level. If a function is defined inside another - // function then gdb prefers the definition at top level and but does not - // expect specification DIE in parent function. So avoid creating - // specification DIE for a function defined inside a function. - DIScope SPContext = resolve(SP.getContext()); - if (SP.isDefinition() && !SPContext.isCompileUnit() && - !SPContext.isFile() && !isSubprogramContext(SPContext)) { - SPCU.addFlag(*SPDie, dwarf::DW_AT_declaration); - - // Add arguments. - DICompositeType SPTy = SP.getType(); - DIArray Args = SPTy.getTypeArray(); - uint16_t SPTag = SPTy.getTag(); - if (SPTag == dwarf::DW_TAG_subroutine_type) - SPCU.constructSubprogramArguments(*SPDie, Args); - DIE *SPDeclDie = SPDie; - SPDie = - &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, SPCU.getUnitDie()); - SPCU.addDIEEntry(*SPDie, dwarf::DW_AT_specification, *SPDeclDie); - } - } - } + DIE *SPDie = SPCU.getOrCreateSubprogramDIE(SP); attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym); @@ -420,6 +384,16 @@ void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE, TheCU.addRangeList(std::move(List)); } +void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die, + const SmallVectorImpl &Ranges) { + assert(!Ranges.empty()); + if (Ranges.size() == 1) + attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first), + getLabelAfterInsn(Ranges.front().second)); + else + addScopeRangeList(TheCU, Die, Ranges); +} + // Construct new DW_TAG_lexical_block for this scope and attach // DW_AT_low_pc/DW_AT_high_pc labels. std::unique_ptr @@ -432,24 +406,7 @@ DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU, if (Scope->isAbstractScope()) return ScopeDIE; - const SmallVectorImpl &ScopeRanges = Scope->getRanges(); - - // If we have multiple ranges, emit them into the range section. - if (ScopeRanges.size() > 1) { - addScopeRangeList(TheCU, *ScopeDIE, ScopeRanges); - return ScopeDIE; - } - - // Construct the address range for this DIE. - SmallVectorImpl::const_iterator RI = ScopeRanges.begin(); - MCSymbol *Start = getLabelBeforeInsn(RI->first); - MCSymbol *End = getLabelAfterInsn(RI->second); - assert(End && "End label should not be null!"); - - assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); - assert(End->isDefined() && "Invalid end label for an inlined scope!"); - - attachLowHighPC(TheCU, *ScopeDIE, Start, End); + attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges()); return ScopeDIE; } @@ -459,40 +416,18 @@ DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU, std::unique_ptr DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU, LexicalScope *Scope) { - const SmallVectorImpl &ScopeRanges = Scope->getRanges(); - assert(!ScopeRanges.empty() && - "LexicalScope does not have instruction markers!"); - - if (!Scope->getScopeNode()) - return nullptr; + assert(Scope->getScopeNode()); DIScope DS(Scope->getScopeNode()); DISubprogram InlinedSP = getDISubprogram(DS); - DIE *OriginDIE = TheCU.getDIE(InlinedSP); - if (!OriginDIE) { - DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); - return nullptr; - } + // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram + // was inlined from another compile unit. + DIE *OriginDIE = AbstractSPDies[InlinedSP]; + assert(OriginDIE && "Unable to find original DIE for an inlined subprogram."); auto ScopeDIE = make_unique(dwarf::DW_TAG_inlined_subroutine); TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE); - // If we have multiple ranges, emit them into the range section. - if (ScopeRanges.size() > 1) - addScopeRangeList(TheCU, *ScopeDIE, ScopeRanges); - else { - SmallVectorImpl::const_iterator RI = ScopeRanges.begin(); - MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); - MCSymbol *EndLabel = getLabelAfterInsn(RI->second); - - if (!StartLabel || !EndLabel) - llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); - - assert(StartLabel->isDefined() && - "Invalid starting label for an inlined scope!"); - assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); - - attachLowHighPC(TheCU, *ScopeDIE, StartLabel, EndLabel); - } + attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges()); InlinedSubprogramDIEs.insert(OriginDIE); @@ -509,6 +444,16 @@ DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU, return ScopeDIE; } +static std::unique_ptr constructVariableDIE(DwarfCompileUnit &TheCU, + DbgVariable &DV, + const LexicalScope &Scope, + DIE *&ObjectPointer) { + auto Var = TheCU.constructVariableDIE(DV, Scope.isAbstractScope()); + if (DV.isObjectPointer()) + ObjectPointer = Var.get(); + return Var; +} + DIE *DwarfDebug::createScopeChildrenDIE( DwarfCompileUnit &TheCU, LexicalScope *Scope, SmallVectorImpl> &Children) { @@ -517,12 +462,9 @@ DIE *DwarfDebug::createScopeChildrenDIE( // Collect arguments for current function. if (LScopes.isCurrentFunctionScope(Scope)) { for (DbgVariable *ArgDV : CurrentFnArguments) - if (ArgDV) { + if (ArgDV) Children.push_back( - TheCU.constructVariableDIE(*ArgDV, Scope->isAbstractScope())); - if (ArgDV->isObjectPointer()) - ObjectPointer = Children.back().get(); - } + constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer)); // If this is a variadic function, add an unspecified parameter. DISubprogram SP(Scope->getScopeNode()); @@ -535,12 +477,9 @@ DIE *DwarfDebug::createScopeChildrenDIE( } // Collect lexical scope children first. - for (DbgVariable *DV : ScopeVariables.lookup(Scope)) { - Children.push_back( - TheCU.constructVariableDIE(*DV, Scope->isAbstractScope())); - if (DV->isObjectPointer()) - ObjectPointer = Children.back().get(); - } + for (DbgVariable *DV : ScopeVariables.lookup(Scope)) + Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer)); + for (LexicalScope *LS : Scope->getChildren()) if (std::unique_ptr Nested = constructScopeDIE(TheCU, LS)) Children.push_back(std::move(Nested)); @@ -548,16 +487,11 @@ DIE *DwarfDebug::createScopeChildrenDIE( } void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU, - LexicalScope *Scope, - DISubprogram Sub, DIE &ScopeDIE) { + LexicalScope *Scope, DIE &ScopeDIE) { // We create children when the scope DIE is not null. SmallVector, 8> Children; if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children)) - // The declaration will have the object_pointer, otherwise put it on the - // definition. This happens with ObjC blocks that have object_pointer on - // non-member functions. - if (!Sub.getFunctionDeclaration()) - TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer); + TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer); // Add children for (auto &I : Children) @@ -570,14 +504,37 @@ void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU, assert(Scope->isAbstractScope()); assert(!Scope->getInlinedAt()); - DISubprogram Sub(Scope->getScopeNode()); + DISubprogram SP(Scope->getScopeNode()); - ProcessedSPNodes.insert(Sub); + ProcessedSPNodes.insert(SP); - if (DIE *ScopeDIE = TheCU.getDIE(Sub)) { - AbstractSPDies.insert(std::make_pair(Sub, ScopeDIE)); - createAndAddScopeChildren(TheCU, Scope, Sub, *ScopeDIE); - } + DIE *&AbsDef = AbstractSPDies[SP]; + if (AbsDef) + return; + + // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram + // was inlined from another compile unit. + DwarfCompileUnit &SPCU = *SPMap[SP]; + DIE *ContextDIE; + + // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with + // the important distinction that the DIDescriptor is not associated with the + // DIE (since the DIDescriptor will be associated with the concrete DIE, if + // any). It could be refactored to some common utility function. + if (DISubprogram SPDecl = SP.getFunctionDeclaration()) { + ContextDIE = &SPCU.getUnitDie(); + SPCU.getOrCreateSubprogramDIE(SPDecl); + } else + ContextDIE = SPCU.getOrCreateContextDIE(resolve(SP.getContext())); + + // Passing null as the associated DIDescriptor because the abstract definition + // shouldn't be found by lookup. + AbsDef = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, + DIDescriptor()); + SPCU.applySubprogramAttributesToDefinition(SP, *AbsDef); + + SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); + createAndAddScopeChildren(SPCU, Scope, *AbsDef); } DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU, @@ -585,15 +542,15 @@ DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU, assert(Scope && Scope->getScopeNode()); assert(!Scope->getInlinedAt()); assert(!Scope->isAbstractScope()); - assert(DIScope(Scope->getScopeNode()).isSubprogram()); - DISubprogram Sub(Scope->getScopeNode()); + assert(Sub.isSubprogram()); + ProcessedSPNodes.insert(Sub); DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub); - createAndAddScopeChildren(TheCU, Scope, Sub, ScopeDIE); + createAndAddScopeChildren(TheCU, Scope, ScopeDIE); return ScopeDIE; } @@ -617,7 +574,7 @@ std::unique_ptr DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU, // avoid creating un-used children then removing them later when we find out // the scope DIE is null. std::unique_ptr ScopeDIE; - if (Scope->getInlinedAt()) { + if (Scope->getParent() && DS.isSubprogram()) { ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); if (!ScopeDIE) return nullptr; @@ -725,30 +682,6 @@ DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) { return NewCU; } -// Construct subprogram DIE. -void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit &TheCU, - const MDNode *N) { - // FIXME: We should only call this routine once, however, during LTO if a - // program is defined in multiple CUs we could end up calling it out of - // beginModule as we walk the CUs. - - DwarfCompileUnit *&CURef = SPMap[N]; - if (CURef) - return; - CURef = &TheCU; - - DISubprogram SP(N); - if (!SP.isDefinition()) - // This is a method declaration which will be handled while constructing - // class type. - return; - - DIE &SubprogramDie = *TheCU.getOrCreateSubprogramDIE(SP); - - // Expose as a global name. - TheCU.addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext())); -} - void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU, const MDNode *N) { DIImportedEntity Module(N); @@ -798,6 +731,8 @@ void DwarfDebug::beginModule() { const Module *M = MMI->getModule(); + FunctionDIs = makeSubprogramMap(*M); + // If module has named metadata anchors then use them, otherwise scan the // module using debug info finder to collect debug info. NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); @@ -825,7 +760,7 @@ void DwarfDebug::beginModule() { CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i))); DIArray SPs = CUNode.getSubprograms(); for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) - constructSubprogramDIE(CU, SPs.getElement(i)); + SPMap.insert(std::make_pair(SPs.getElement(i), &CU)); DIArray EnumTypes = CUNode.getEnumTypes(); for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) CU.getOrCreateTypeDIE(EnumTypes.getElement(i)); @@ -850,20 +785,60 @@ void DwarfDebug::beginModule() { SectionMap[Asm->getObjFileLowering().getTextSection()]; } -// Attach DW_AT_inline attribute with inlined subprogram DIEs. -void DwarfDebug::computeInlinedDIEs() { - // Attach DW_AT_inline attribute with inlined subprogram DIEs. - for (DIE *ISP : InlinedSubprogramDIEs) - FirstCU->addUInt(*ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); - - for (const auto &AI : AbstractSPDies) { - DIE &ISP = *AI.second; - if (InlinedSubprogramDIEs.count(&ISP)) +void DwarfDebug::finishVariableDefinitions() { + for (const auto &Var : ConcreteVariables) { + DIE *VariableDie = Var->getDIE(); + // FIXME: There shouldn't be any variables without DIEs. + if (!VariableDie) continue; - FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); + // FIXME: Consider the time-space tradeoff of just storing the unit pointer + // in the ConcreteVariables list, rather than looking it up again here. + // DIE::getUnit isn't simple - it walks parent pointers, etc. + DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit()); + assert(Unit); + DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable()); + if (AbsVar && AbsVar->getDIE()) { + Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin, + *AbsVar->getDIE()); + } else + Unit->applyVariableAttributes(*Var, *VariableDie); } } +void DwarfDebug::finishSubprogramDefinitions() { + const Module *M = MMI->getModule(); + + NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); + for (MDNode *N : CU_Nodes->operands()) { + DICompileUnit TheCU(N); + // Construct subprogram DIE and add variables DIEs. + DwarfCompileUnit *SPCU = + static_cast(CUMap.lookup(TheCU)); + DIArray Subprograms = TheCU.getSubprograms(); + for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { + DISubprogram SP(Subprograms.getElement(i)); + // Perhaps the subprogram is in another CU (such as due to comdat + // folding, etc), in which case ignore it here. + if (SPMap[SP] != SPCU) + continue; + DIE *D = SPCU->getDIE(SP); + if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) { + if (D) + // If this subprogram has an abstract definition, reference that + SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE); + } else { + if (!D) + // Lazily construct the subprogram if we didn't see either concrete or + // inlined versions during codegen. + D = SPCU->getOrCreateSubprogramDIE(SP); + // And attach the attributes + SPCU->applySubprogramAttributesToDefinition(SP, *D); + } + } + } +} + + // Collect info for variables that were optimized out. void DwarfDebug::collectDeadVariables() { const Module *M = MMI->getModule(); @@ -871,33 +846,34 @@ void DwarfDebug::collectDeadVariables() { if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { for (MDNode *N : CU_Nodes->operands()) { DICompileUnit TheCU(N); + // Construct subprogram DIE and add variables DIEs. + DwarfCompileUnit *SPCU = + static_cast(CUMap.lookup(TheCU)); + assert(SPCU && "Unable to find Compile Unit!"); DIArray Subprograms = TheCU.getSubprograms(); for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { DISubprogram SP(Subprograms.getElement(i)); if (ProcessedSPNodes.count(SP) != 0) continue; - if (!SP.isSubprogram()) - continue; - if (!SP.isDefinition()) - continue; + assert(SP.isSubprogram() && + "CU's subprogram list contains a non-subprogram"); + assert(SP.isDefinition() && + "CU's subprogram list contains a subprogram declaration"); DIArray Variables = SP.getVariables(); if (Variables.getNumElements() == 0) continue; - // Construct subprogram DIE and add variables DIEs. - DwarfCompileUnit *SPCU = - static_cast(CUMap.lookup(TheCU)); - assert(SPCU && "Unable to find Compile Unit!"); - // FIXME: See the comment in constructSubprogramDIE about duplicate - // subprogram DIEs. - constructSubprogramDIE(*SPCU, SP); - DIE *SPDIE = SPCU->getDIE(SP); + DIE *SPDIE = AbstractSPDies.lookup(SP); + if (!SPDIE) + SPDIE = SPCU->getDIE(SP); + assert(SPDIE); for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { DIVariable DV(Variables.getElement(vi)); - if (!DV.isVariable()) - continue; - DbgVariable NewVar(DV, nullptr, this); - SPDIE->addChild(SPCU->constructVariableDIE(NewVar, false)); + assert(DV.isVariable()); + DbgVariable NewVar(DV, this); + auto VariableDie = SPCU->constructVariableDIE(NewVar); + SPCU->applyVariableAttributes(NewVar, *VariableDie); + SPDIE->addChild(std::move(VariableDie)); } } } @@ -905,12 +881,13 @@ void DwarfDebug::collectDeadVariables() { } void DwarfDebug::finalizeModuleInfo() { + finishSubprogramDefinitions(); + + finishVariableDefinitions(); + // Collect info for variables that were optimized out. collectDeadVariables(); - // Attach DW_AT_inline attribute with inlined subprogram DIEs. - computeInlinedDIEs(); - // Handle anything that needs to be done on a per-unit basis after // all other generation. for (const auto &TheU : getUnits()) { @@ -1064,9 +1041,9 @@ void DwarfDebug::endModule() { emitDebugInfoDWO(); emitDebugAbbrevDWO(); emitDebugLineDWO(); + emitDebugLocDWO(); // Emit DWO addresses. AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection()); - emitDebugLocDWO(); } else // Emit info into a debug loc section. emitDebugLoc(); @@ -1087,29 +1064,58 @@ void DwarfDebug::endModule() { // clean up. SPMap.clear(); + AbstractVariables.clear(); // Reset these for the next Module if we have one. FirstCU = nullptr; } // Find abstract variable, if any, associated with Var. -DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, - DebugLoc ScopeLoc) { +DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV, + DIVariable &Cleansed) { LLVMContext &Ctx = DV->getContext(); // More then one inlined variable corresponds to one abstract variable. - DIVariable Var = cleanseInlinedVariable(DV, Ctx); - DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); - if (AbsDbgVariable) - return AbsDbgVariable; + // FIXME: This duplication of variables when inlining should probably be + // removed. It's done to allow each DIVariable to describe its location + // because the DebugLoc on the dbg.value/declare isn't accurate. We should + // make it accurate then remove this duplication/cleansing stuff. + Cleansed = cleanseInlinedVariable(DV, Ctx); + auto I = AbstractVariables.find(Cleansed); + if (I != AbstractVariables.end()) + return I->second.get(); + return nullptr; +} - LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); - if (!Scope) - return nullptr; +DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) { + DIVariable Cleansed; + return getExistingAbstractVariable(DV, Cleansed); +} - AbsDbgVariable = new DbgVariable(Var, nullptr, this); - addScopeVariable(Scope, AbsDbgVariable); - AbstractVariables[Var] = AbsDbgVariable; - return AbsDbgVariable; +void DwarfDebug::createAbstractVariable(const DIVariable &Var, + LexicalScope *Scope) { + auto AbsDbgVariable = make_unique(Var, this); + addScopeVariable(Scope, AbsDbgVariable.get()); + AbstractVariables[Var] = std::move(AbsDbgVariable); +} + +void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV, + const MDNode *ScopeNode) { + DIVariable Cleansed = DV; + if (getExistingAbstractVariable(DV, Cleansed)) + return; + + createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode)); +} + +void +DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV, + const MDNode *ScopeNode) { + DIVariable Cleansed = DV; + if (getExistingAbstractVariable(DV, Cleansed)) + return; + + if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode)) + createAbstractVariable(Cleansed, Scope); } // If Var is a current function argument then add it to CurrentFnArguments list. @@ -1148,13 +1154,11 @@ void DwarfDebug::collectVariableInfoFromMMITable( if (!Scope) continue; - DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc); - DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique(DV, this)); + DbgVariable *RegVar = ConcreteVariables.back().get(); RegVar->setFrameIndex(VI.Slot); - if (!addCurrentFnArgument(RegVar, Scope)) - addScopeVariable(Scope, RegVar); - if (AbsDbgVariable) - AbsDbgVariable->setFrameIndex(VI.Slot); + addScopeVariable(Scope, RegVar); } } @@ -1192,45 +1196,41 @@ DwarfDebug::collectVariableInfo(SmallPtrSet &Processed) { // Grab the variable info that was squirreled away in the MMI side-table. collectVariableInfoFromMMITable(Processed); - for (const MDNode *Var : UserVariables) { - if (Processed.count(Var)) + for (const auto &I : DbgValues) { + DIVariable DV(I.first); + if (Processed.count(DV)) continue; - // History contains relevant DBG_VALUE instructions for Var and instructions - // clobbering it. - SmallVectorImpl &History = DbgValues[Var]; - if (History.empty()) + // Instruction ranges, specifying where DV is accessible. + const auto &Ranges = I.second; + if (Ranges.empty()) continue; - const MachineInstr *MInsn = History.front(); - DIVariable DV(Var); LexicalScope *Scope = nullptr; if (DV.getTag() == dwarf::DW_TAG_arg_variable && DISubprogram(DV.getContext()).describes(CurFn->getFunction())) Scope = LScopes.getCurrentFunctionScope(); - else if (MDNode *IA = DV.getInlinedAt()) - Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); - else - Scope = LScopes.findLexicalScope(cast(DV->getOperand(1))); + else if (MDNode *IA = DV.getInlinedAt()) { + DebugLoc DL = DebugLoc::getFromDILocation(IA); + Scope = LScopes.findInlinedScope(DebugLoc::get( + DL.getLine(), DL.getCol(), DV.getContext(), IA)); + } else + Scope = LScopes.findLexicalScope(DV.getContext()); // If variable scope is not found then skip this variable. if (!Scope) continue; Processed.insert(DV); + const MachineInstr *MInsn = Ranges.front().first; assert(MInsn->isDebugValue() && "History must begin with debug value"); - DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); - DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); - if (!addCurrentFnArgument(RegVar, Scope)) - addScopeVariable(Scope, RegVar); - if (AbsVar) - AbsVar->setMInsn(MInsn); - - // Simplify ranges that are fully coalesced. - if (History.size() <= 1 || - (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) { - RegVar->setMInsn(MInsn); + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique(MInsn, this)); + DbgVariable *RegVar = ConcreteVariables.back().get(); + addScopeVariable(Scope, RegVar); + + // Check if the first DBG_VALUE is valid for the rest of the function. + if (Ranges.size() == 1 && Ranges.front().second == nullptr) continue; - } // Handle multiple DBG_VALUE instructions describing one variable. RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); @@ -1240,42 +1240,34 @@ DwarfDebug::collectVariableInfo(SmallPtrSet &Processed) { LocList.Label = Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1); SmallVector &DebugLoc = LocList.List; - for (SmallVectorImpl::const_iterator - HI = History.begin(), - HE = History.end(); - HI != HE; ++HI) { - const MachineInstr *Begin = *HI; + for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) { + const MachineInstr *Begin = I->first; + const MachineInstr *End = I->second; assert(Begin->isDebugValue() && "Invalid History entry"); - // Check if DBG_VALUE is truncating a range. + // Check if a variable is unaccessible in this range. if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() && !Begin->getOperand(0).getReg()) continue; + DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin); + if (End != nullptr) + DEBUG(dbgs() << "\t" << *End); + else + DEBUG(dbgs() << "\tNULL\n"); - // Compute the range for a register location. - const MCSymbol *FLabel = getLabelBeforeInsn(Begin); - const MCSymbol *SLabel = nullptr; - - if (HI + 1 == HE) - // If Begin is the last instruction in History then its value is valid - // until the end of the function. - SLabel = FunctionEndSym; - else { - const MachineInstr *End = HI[1]; - DEBUG(dbgs() << "DotDebugLoc Pair:\n" - << "\t" << *Begin << "\t" << *End << "\n"); - if (End->isDebugValue()) - SLabel = getLabelBeforeInsn(End); - else { - // End is a normal instruction clobbering the range. - SLabel = getLabelAfterInsn(End); - assert(SLabel && "Forgot label after clobber instruction"); - ++HI; - } - } + const MCSymbol *StartLabel = getLabelBeforeInsn(Begin); + assert(StartLabel && "Forgot label before DBG_VALUE starting a range!"); + + const MCSymbol *EndLabel; + if (End != nullptr) + EndLabel = getLabelAfterInsn(End); + else if (std::next(I) == Ranges.end()) + EndLabel = FunctionEndSym; + else + EndLabel = getLabelBeforeInsn(std::next(I)->first); + assert(EndLabel && "Forgot label after instruction ending a range!"); - // The value is valid until the next DBG_VALUE or clobber. - DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU); + DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU); if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc)) DebugLoc.push_back(std::move(Loc)); } @@ -1285,10 +1277,14 @@ DwarfDebug::collectVariableInfo(SmallPtrSet &Processed) { DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { DIVariable DV(Variables.getElement(i)); - if (!DV || !DV.isVariable() || !Processed.insert(DV)) + assert(DV.isVariable()); + if (!Processed.insert(DV)) continue; - if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) - addScopeVariable(Scope, new DbgVariable(DV, nullptr, this)); + if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) { + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique(DV, this)); + addScopeVariable(Scope, ConcreteVariables.back().get()); + } } } @@ -1402,6 +1398,17 @@ void DwarfDebug::identifyScopeMarkers() { } } +static DebugLoc findPrologueEndLoc(const MachineFunction *MF) { + // First known non-DBG_VALUE and non-frame setup location marks + // the beginning of the function body. + for (const auto &MBB : *MF) + for (const auto &MI : MBB) + if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) && + !MI.getDebugLoc().isUnknown()) + return MI.getDebugLoc(); + return DebugLoc(); +} + // Gather pre-function debug information. Assumes being called immediately // after the function entry point has been emitted. void DwarfDebug::beginFunction(const MachineFunction *MF) { @@ -1411,13 +1418,17 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { if (!MMI->hasDebugInfo()) return; + auto DI = FunctionDIs.find(MF->getFunction()); + if (DI == FunctionDIs.end()) + return; + // Grab the lexical scopes for the function, if we don't have any of those // then we're not going to be able to do anything. LScopes.initialize(*MF); if (LScopes.empty()) return; - assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); + assert(DbgValues.empty() && "DbgValues map wasn't cleaned!"); // Make sure that each lexical scope will have a begin/end label. identifyScopeMarkers(); @@ -1426,6 +1437,14 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { // belongs to so that we add to the correct per-cu line table in the // non-asm case. LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); + // FnScope->getScopeNode() and DI->second should represent the same function, + // though they may not be the same MDNode due to inline functions merged in + // LTO where the debug info metadata still differs (either due to distinct + // written differences - two versions of a linkonce_odr function + // written/copied into two separate files, or some sub-optimal metadata that + // isn't structurally identical (see: file path/name info from clang, which + // includes the directory of the cpp file being built, even when the file name + // is absolute (such as an <> lookup header))) DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); assert(TheCU && "Unable to find compile unit!"); if (Asm->OutStreamer.hasRawTextSupport()) @@ -1439,36 +1458,13 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { // Assumes in correct section after the entry point. Asm->OutStreamer.EmitLabel(FunctionBeginSym); - // Collect user variables, find the end of the prologue. - for (const auto &MBB : *MF) { - for (MachineBasicBlock::const_iterator II = MBB.begin(), IE = MBB.end(); - II != IE; ++II) { - const MachineInstr *MI = II; - if (MI->isDebugValue()) { - assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); - // Keep track of user variables in order of appearance. Store the set - // of variables we've already seen as a set of keys in DbgValues. - const MDNode *Var = MI->getDebugVariable(); - auto IterPair = DbgValues.insert( - std::make_pair(Var, SmallVector())); - if (IterPair.second) - UserVariables.push_back(Var); - } else if (!MI->getFlag(MachineInstr::FrameSetup) && - PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown()) { - // First known non-DBG_VALUE and non-frame setup location marks - // the beginning of the function body. - PrologEndLoc = MI->getDebugLoc(); - } - } - } - // Calculate history for local variables. calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues); // Request labels for the full history. - for (auto &I : DbgValues) { - const SmallVectorImpl &History = I.second; - if (History.empty()) + for (const auto &I : DbgValues) { + const auto &Ranges = I.second; + if (Ranges.empty()) continue; // The first mention of a function argument gets the FunctionBeginSym @@ -1476,13 +1472,12 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { DIVariable DV(I.first); if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && getDISubprogram(DV.getContext()).describes(MF->getFunction())) - LabelsBeforeInsn[History.front()] = FunctionBeginSym; + LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym; - for (const MachineInstr *MI : History) { - if (MI->isDebugValue()) - requestLabelBeforeInsn(MI); - else - requestLabelAfterInsn(MI); + for (const auto &Range : Ranges) { + requestLabelBeforeInsn(Range.first); + if (Range.second) + requestLabelAfterInsn(Range.second); } } @@ -1490,6 +1485,7 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { PrevLabel = FunctionBeginSym; // Record beginning of function. + PrologEndLoc = findPrologueEndLoc(MF); if (!PrologEndLoc.isUnknown()) { DebugLoc FnStartDL = PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext()); @@ -1503,6 +1499,8 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) { } void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { + if (addCurrentFnArgument(Var, LS)) + return; SmallVectorImpl &Vars = ScopeVariables[LS]; DIVariable DV = Var->getVariable(); // Variables with positive arg numbers are parameters. @@ -1544,7 +1542,8 @@ void DwarfDebug::endFunction(const MachineFunction *MF) { assert(CurFn == MF); assert(CurFn != nullptr); - if (!MMI->hasDebugInfo() || LScopes.empty()) { + if (!MMI->hasDebugInfo() || LScopes.empty() || + !FunctionDIs.count(MF->getFunction())) { // If we don't have a lexical scope for this function then there will // be a hole in the range information. Keep note of this by setting the // previously used section to nullptr. @@ -1571,25 +1570,17 @@ void DwarfDebug::endFunction(const MachineFunction *MF) { // Construct abstract scopes. for (LexicalScope *AScope : LScopes.getAbstractScopesList()) { DISubprogram SP(AScope->getScopeNode()); - if (SP.isSubprogram()) { - // Collect info for variables that were optimized out. - DIArray Variables = SP.getVariables(); - for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { - DIVariable DV(Variables.getElement(i)); - if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) - continue; - // Check that DbgVariable for DV wasn't created earlier, when - // findAbstractVariable() was called for inlined instance of DV. - LLVMContext &Ctx = DV->getContext(); - DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); - if (AbstractVariables.lookup(CleanDV)) - continue; - if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) - addScopeVariable(Scope, new DbgVariable(DV, nullptr, this)); - } + assert(SP.isSubprogram()); + // Collect info for variables that were optimized out. + DIArray Variables = SP.getVariables(); + for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { + DIVariable DV(Variables.getElement(i)); + assert(DV && DV.isVariable()); + if (!ProcessedVars.insert(DV)) + continue; + ensureAbstractVariableIsCreated(DV, DV.getContext()); } - if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) - constructAbstractSubprogramScopeDIE(TheCU, AScope); + constructAbstractSubprogramScopeDIE(TheCU, AScope); } DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope); @@ -1603,13 +1594,12 @@ void DwarfDebug::endFunction(const MachineFunction *MF) { PrevCU = &TheCU; // Clear debug info - for (auto &I : ScopeVariables) - DeleteContainerPointers(I.second); + // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the + // DbgVariables except those that are also in AbstractVariables (since they + // can be used cross-function) ScopeVariables.clear(); - DeleteContainerPointers(CurrentFnArguments); - UserVariables.clear(); + CurrentFnArguments.clear(); DbgValues.clear(); - AbstractVariables.clear(); LabelsBeforeInsn.clear(); LabelsAfterInsn.clear(); PrevLabel = nullptr; @@ -1624,32 +1614,12 @@ void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, StringRef Dir; unsigned Src = 1; unsigned Discriminator = 0; - if (S) { - DIDescriptor Scope(S); - - if (Scope.isCompileUnit()) { - DICompileUnit CU(S); - Fn = CU.getFilename(); - Dir = CU.getDirectory(); - } else if (Scope.isFile()) { - DIFile F(S); - Fn = F.getFilename(); - Dir = F.getDirectory(); - } else if (Scope.isSubprogram()) { - DISubprogram SP(S); - Fn = SP.getFilename(); - Dir = SP.getDirectory(); - } else if (Scope.isLexicalBlockFile()) { - DILexicalBlockFile DBF(S); - Fn = DBF.getFilename(); - Dir = DBF.getDirectory(); - } else if (Scope.isLexicalBlock()) { - DILexicalBlock DB(S); - Fn = DB.getFilename(); - Dir = DB.getDirectory(); - Discriminator = DB.getDiscriminator(); - } else - llvm_unreachable("Unexpected scope info"); + if (DIScope Scope = DIScope(S)) { + assert(Scope.isScope()); + Fn = Scope.getFilename(); + Dir = Scope.getDirectory(); + if (Scope.isLexicalBlock()) + Discriminator = DILexicalBlock(S).getDiscriminator(); unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID(); Src = static_cast(*InfoHolder.getUnits()[CUID]) @@ -1670,9 +1640,12 @@ void DwarfDebug::emitSectionLabels() { // Dwarf sections base addresses. DwarfInfoSectionSym = emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); - if (useSplitDwarf()) + if (useSplitDwarf()) { DwarfInfoDWOSectionSym = emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo"); + DwarfTypesDWOSectionSym = + emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo"); + } DwarfAbbrevSectionSym = emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); if (useSplitDwarf()) @@ -2436,9 +2409,9 @@ void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU, bool TopLevelType = TypeUnitsUnderConstruction.empty(); AddrPool.resetUsedFlag(); - auto OwnedUnit = - make_unique(InfoHolder.getUnits().size(), CU, Asm, this, - &InfoHolder, getDwoLineTable(CU)); + auto OwnedUnit = make_unique( + InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm, + this, &InfoHolder, getDwoLineTable(CU)); DwarfTypeUnit &NewTU = *OwnedUnit; DIE &UnitDie = NewTU.getUnitDie(); TU = &NewTU; @@ -2451,13 +2424,14 @@ void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU, uint64_t Signature = makeTypeSignature(Identifier); NewTU.setTypeSignature(Signature); - if (!useSplitDwarf()) + if (useSplitDwarf()) + NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection(), + DwarfTypesDWOSectionSym); + else { CU.applyStmtList(UnitDie); - - NewTU.initSection( - useSplitDwarf() - ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature) - : Asm->getObjFileLowering().getDwarfTypesSection(Signature)); + NewTU.initSection( + Asm->getObjFileLowering().getDwarfTypesSection(Signature)); + } NewTU.setType(NewTU.createTypeDIE(CTy)); @@ -2496,6 +2470,11 @@ void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU, void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D, MCSymbol *Begin, MCSymbol *End) { + assert(Begin && "Begin label should not be null!"); + assert(End && "End label should not be null!"); + assert(Begin->isDefined() && "Invalid starting label"); + assert(End->isDefined() && "Invalid end label"); + Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin); if (DwarfVersion < 4) Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);