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Diffstat (limited to 'llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp | 1318 |
1 files changed, 1318 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp new file mode 100644 index 000000000000..a61c98ec1c18 --- /dev/null +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp @@ -0,0 +1,1318 @@ +//===- llvm/CodeGen/DwarfCompileUnit.cpp - Dwarf Compile Units ------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file contains support for constructing a dwarf compile unit. +// +//===----------------------------------------------------------------------===// + +#include "DwarfCompileUnit.h" +#include "AddressPool.h" +#include "DwarfDebug.h" +#include "DwarfExpression.h" +#include "DwarfUnit.h" +#include "llvm/ADT/None.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/BinaryFormat/Dwarf.h" +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/CodeGen/DIE.h" +#include "llvm/CodeGen/LexicalScopes.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/MachineOperand.h" +#include "llvm/CodeGen/TargetFrameLowering.h" +#include "llvm/CodeGen/TargetRegisterInfo.h" +#include "llvm/CodeGen/TargetSubtargetInfo.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/DebugInfoMetadata.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/MC/MCSection.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MachineLocation.h" +#include "llvm/Support/Casting.h" +#include "llvm/Target/TargetLoweringObjectFile.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include <algorithm> +#include <cassert> +#include <cstdint> +#include <iterator> +#include <memory> +#include <string> +#include <utility> + +using namespace llvm; + +DwarfCompileUnit::DwarfCompileUnit(unsigned UID, const DICompileUnit *Node, + AsmPrinter *A, DwarfDebug *DW, + DwarfFile *DWU) + : DwarfUnit(dwarf::DW_TAG_compile_unit, Node, A, DW, DWU), UniqueID(UID) { + insertDIE(Node, &getUnitDie()); + MacroLabelBegin = Asm->createTempSymbol("cu_macro_begin"); +} + +/// addLabelAddress - Add a dwarf label attribute data and value using +/// DW_FORM_addr or DW_FORM_GNU_addr_index. +void DwarfCompileUnit::addLabelAddress(DIE &Die, dwarf::Attribute Attribute, + const MCSymbol *Label) { + // Don't use the address pool in non-fission or in the skeleton unit itself. + // FIXME: Once GDB supports this, it's probably worthwhile using the address + // pool from the skeleton - maybe even in non-fission (possibly fewer + // relocations by sharing them in the pool, but we have other ideas about how + // to reduce the number of relocations as well/instead). + if ((!DD->useSplitDwarf() || !Skeleton) && DD->getDwarfVersion() < 5) + return addLocalLabelAddress(Die, Attribute, Label); + + if (Label) + DD->addArangeLabel(SymbolCU(this, Label)); + + unsigned idx = DD->getAddressPool().getIndex(Label); + Die.addValue(DIEValueAllocator, Attribute, + DD->getDwarfVersion() >= 5 ? dwarf::DW_FORM_addrx + : dwarf::DW_FORM_GNU_addr_index, + DIEInteger(idx)); +} + +void DwarfCompileUnit::addLocalLabelAddress(DIE &Die, + dwarf::Attribute Attribute, + const MCSymbol *Label) { + if (Label) + DD->addArangeLabel(SymbolCU(this, Label)); + + if (Label) + Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr, + DIELabel(Label)); + else + Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr, + DIEInteger(0)); +} + +unsigned DwarfCompileUnit::getOrCreateSourceID(const DIFile *File) { + // If we print assembly, we can't separate .file entries according to + // compile units. Thus all files will belong to the default compile unit. + + // FIXME: add a better feature test than hasRawTextSupport. Even better, + // extend .file to support this. + unsigned CUID = Asm->OutStreamer->hasRawTextSupport() ? 0 : getUniqueID(); + if (!File) + return Asm->OutStreamer->EmitDwarfFileDirective(0, "", "", None, None, CUID); + return Asm->OutStreamer->EmitDwarfFileDirective( + 0, File->getDirectory(), File->getFilename(), getMD5AsBytes(File), + File->getSource(), CUID); +} + +DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE( + const DIGlobalVariable *GV, ArrayRef<GlobalExpr> GlobalExprs) { + // Check for pre-existence. + if (DIE *Die = getDIE(GV)) + return Die; + + assert(GV); + + auto *GVContext = GV->getScope(); + const DIType *GTy = GV->getType(); + + // Construct the context before querying for the existence of the DIE in + // case such construction creates the DIE. + auto *CB = GVContext ? dyn_cast<DICommonBlock>(GVContext) : nullptr; + DIE *ContextDIE = CB ? getOrCreateCommonBlock(CB, GlobalExprs) + : getOrCreateContextDIE(GVContext); + + // Add to map. + DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV); + DIScope *DeclContext; + if (auto *SDMDecl = GV->getStaticDataMemberDeclaration()) { + DeclContext = SDMDecl->getScope(); + assert(SDMDecl->isStaticMember() && "Expected static member decl"); + assert(GV->isDefinition()); + // We need the declaration DIE that is in the static member's class. + DIE *VariableSpecDIE = getOrCreateStaticMemberDIE(SDMDecl); + addDIEEntry(*VariableDIE, dwarf::DW_AT_specification, *VariableSpecDIE); + // If the global variable's type is different from the one in the class + // member type, assume that it's more specific and also emit it. + if (GTy != SDMDecl->getBaseType()) + addType(*VariableDIE, GTy); + } else { + DeclContext = GV->getScope(); + // Add name and type. + addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName()); + addType(*VariableDIE, GTy); + + // Add scoping info. + if (!GV->isLocalToUnit()) + addFlag(*VariableDIE, dwarf::DW_AT_external); + + // Add line number info. + addSourceLine(*VariableDIE, GV); + } + + if (!GV->isDefinition()) + addFlag(*VariableDIE, dwarf::DW_AT_declaration); + else + addGlobalName(GV->getName(), *VariableDIE, DeclContext); + + if (uint32_t AlignInBytes = GV->getAlignInBytes()) + addUInt(*VariableDIE, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata, + AlignInBytes); + + if (MDTuple *TP = GV->getTemplateParams()) + addTemplateParams(*VariableDIE, DINodeArray(TP)); + + // Add location. + addLocationAttribute(VariableDIE, GV, GlobalExprs); + + return VariableDIE; +} + +void DwarfCompileUnit::addLocationAttribute( + DIE *VariableDIE, const DIGlobalVariable *GV, ArrayRef<GlobalExpr> GlobalExprs) { + bool addToAccelTable = false; + DIELoc *Loc = nullptr; + Optional<unsigned> NVPTXAddressSpace; + std::unique_ptr<DIEDwarfExpression> DwarfExpr; + for (const auto &GE : GlobalExprs) { + const GlobalVariable *Global = GE.Var; + const DIExpression *Expr = GE.Expr; + + // For compatibility with DWARF 3 and earlier, + // DW_AT_location(DW_OP_constu, X, DW_OP_stack_value) becomes + // DW_AT_const_value(X). + if (GlobalExprs.size() == 1 && Expr && Expr->isConstant()) { + addToAccelTable = true; + addConstantValue(*VariableDIE, /*Unsigned=*/true, Expr->getElement(1)); + break; + } + + // We cannot describe the location of dllimport'd variables: the + // computation of their address requires loads from the IAT. + if (Global && Global->hasDLLImportStorageClass()) + continue; + + // Nothing to describe without address or constant. + if (!Global && (!Expr || !Expr->isConstant())) + continue; + + if (Global && Global->isThreadLocal() && + !Asm->getObjFileLowering().supportDebugThreadLocalLocation()) + continue; + + if (!Loc) { + addToAccelTable = true; + Loc = new (DIEValueAllocator) DIELoc; + DwarfExpr = std::make_unique<DIEDwarfExpression>(*Asm, *this, *Loc); + } + + if (Expr) { + // According to + // https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf + // cuda-gdb requires DW_AT_address_class for all variables to be able to + // correctly interpret address space of the variable address. + // Decode DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef + // sequence for the NVPTX + gdb target. + unsigned LocalNVPTXAddressSpace; + if (Asm->TM.getTargetTriple().isNVPTX() && DD->tuneForGDB()) { + const DIExpression *NewExpr = + DIExpression::extractAddressClass(Expr, LocalNVPTXAddressSpace); + if (NewExpr != Expr) { + Expr = NewExpr; + NVPTXAddressSpace = LocalNVPTXAddressSpace; + } + } + DwarfExpr->addFragmentOffset(Expr); + } + + if (Global) { + const MCSymbol *Sym = Asm->getSymbol(Global); + if (Global->isThreadLocal()) { + if (Asm->TM.useEmulatedTLS()) { + // TODO: add debug info for emulated thread local mode. + } else { + // FIXME: Make this work with -gsplit-dwarf. + unsigned PointerSize = Asm->getDataLayout().getPointerSize(); + assert((PointerSize == 4 || PointerSize == 8) && + "Add support for other sizes if necessary"); + // Based on GCC's support for TLS: + if (!DD->useSplitDwarf()) { + // 1) Start with a constNu of the appropriate pointer size + addUInt(*Loc, dwarf::DW_FORM_data1, + PointerSize == 4 ? dwarf::DW_OP_const4u + : dwarf::DW_OP_const8u); + // 2) containing the (relocated) offset of the TLS variable + // within the module's TLS block. + addExpr(*Loc, dwarf::DW_FORM_udata, + Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym)); + } else { + addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index); + addUInt(*Loc, dwarf::DW_FORM_udata, + DD->getAddressPool().getIndex(Sym, /* TLS */ true)); + } + // 3) followed by an OP to make the debugger do a TLS lookup. + addUInt(*Loc, dwarf::DW_FORM_data1, + DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address + : dwarf::DW_OP_form_tls_address); + } + } else { + DD->addArangeLabel(SymbolCU(this, Sym)); + addOpAddress(*Loc, Sym); + } + } + // Global variables attached to symbols are memory locations. + // It would be better if this were unconditional, but malformed input that + // mixes non-fragments and fragments for the same variable is too expensive + // to detect in the verifier. + if (DwarfExpr->isUnknownLocation()) + DwarfExpr->setMemoryLocationKind(); + DwarfExpr->addExpression(Expr); + } + if (Asm->TM.getTargetTriple().isNVPTX() && DD->tuneForGDB()) { + // According to + // https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf + // cuda-gdb requires DW_AT_address_class for all variables to be able to + // correctly interpret address space of the variable address. + const unsigned NVPTX_ADDR_global_space = 5; + addUInt(*VariableDIE, dwarf::DW_AT_address_class, dwarf::DW_FORM_data1, + NVPTXAddressSpace ? *NVPTXAddressSpace : NVPTX_ADDR_global_space); + } + if (Loc) + addBlock(*VariableDIE, dwarf::DW_AT_location, DwarfExpr->finalize()); + + if (DD->useAllLinkageNames()) + addLinkageName(*VariableDIE, GV->getLinkageName()); + + if (addToAccelTable) { + DD->addAccelName(*CUNode, GV->getName(), *VariableDIE); + + // If the linkage name is different than the name, go ahead and output + // that as well into the name table. + if (GV->getLinkageName() != "" && GV->getName() != GV->getLinkageName() && + DD->useAllLinkageNames()) + DD->addAccelName(*CUNode, GV->getLinkageName(), *VariableDIE); + } +} + +DIE *DwarfCompileUnit::getOrCreateCommonBlock( + const DICommonBlock *CB, ArrayRef<GlobalExpr> GlobalExprs) { + // Construct the context before querying for the existence of the DIE in case + // such construction creates the DIE. + DIE *ContextDIE = getOrCreateContextDIE(CB->getScope()); + + if (DIE *NDie = getDIE(CB)) + return NDie; + DIE &NDie = createAndAddDIE(dwarf::DW_TAG_common_block, *ContextDIE, CB); + StringRef Name = CB->getName().empty() ? "_BLNK_" : CB->getName(); + addString(NDie, dwarf::DW_AT_name, Name); + addGlobalName(Name, NDie, CB->getScope()); + if (CB->getFile()) + addSourceLine(NDie, CB->getLineNo(), CB->getFile()); + if (DIGlobalVariable *V = CB->getDecl()) + getCU().addLocationAttribute(&NDie, V, GlobalExprs); + return &NDie; +} + +void DwarfCompileUnit::addRange(RangeSpan Range) { + bool SameAsPrevCU = this == DD->getPrevCU(); + DD->setPrevCU(this); + // If we have no current ranges just add the range and return, otherwise, + // check the current section and CU against the previous section and CU we + // emitted into and the subprogram was contained within. If these are the + // same then extend our current range, otherwise add this as a new range. + if (CURanges.empty() || !SameAsPrevCU || + (&CURanges.back().End->getSection() != + &Range.End->getSection())) { + CURanges.push_back(Range); + return; + } + + CURanges.back().End = Range.End; +} + +void DwarfCompileUnit::initStmtList() { + if (CUNode->isDebugDirectivesOnly()) + return; + + // Define start line table label for each Compile Unit. + MCSymbol *LineTableStartSym; + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + if (DD->useSectionsAsReferences()) { + LineTableStartSym = TLOF.getDwarfLineSection()->getBeginSymbol(); + } else { + LineTableStartSym = + Asm->OutStreamer->getDwarfLineTableSymbol(getUniqueID()); + } + + // DW_AT_stmt_list is a offset of line number information for this + // compile unit in debug_line section. For split dwarf this is + // left in the skeleton CU and so not included. + // The line table entries are not always emitted in assembly, so it + // is not okay to use line_table_start here. + StmtListValue = + addSectionLabel(getUnitDie(), dwarf::DW_AT_stmt_list, LineTableStartSym, + TLOF.getDwarfLineSection()->getBeginSymbol()); +} + +void DwarfCompileUnit::applyStmtList(DIE &D) { + D.addValue(DIEValueAllocator, *StmtListValue); +} + +void DwarfCompileUnit::attachLowHighPC(DIE &D, const MCSymbol *Begin, + const 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"); + + addLabelAddress(D, dwarf::DW_AT_low_pc, Begin); + if (DD->getDwarfVersion() < 4) + addLabelAddress(D, dwarf::DW_AT_high_pc, End); + else + addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin); +} + +// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc +// and DW_AT_high_pc attributes. If there are global variables in this +// scope then create and insert DIEs for these variables. +DIE &DwarfCompileUnit::updateSubprogramScopeDIE(const DISubprogram *SP) { + DIE *SPDie = getOrCreateSubprogramDIE(SP, includeMinimalInlineScopes()); + + attachLowHighPC(*SPDie, Asm->getFunctionBegin(), Asm->getFunctionEnd()); + if (DD->useAppleExtensionAttributes() && + !DD->getCurrentFunction()->getTarget().Options.DisableFramePointerElim( + *DD->getCurrentFunction())) + addFlag(*SPDie, dwarf::DW_AT_APPLE_omit_frame_ptr); + + // Only include DW_AT_frame_base in full debug info + if (!includeMinimalInlineScopes()) { + if (Asm->MF->getTarget().getTargetTriple().isNVPTX()) { + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_call_frame_cfa); + addBlock(*SPDie, dwarf::DW_AT_frame_base, Loc); + } else { + const TargetRegisterInfo *RI = Asm->MF->getSubtarget().getRegisterInfo(); + MachineLocation Location(RI->getFrameRegister(*Asm->MF)); + if (Register::isPhysicalRegister(Location.getReg())) + addAddress(*SPDie, dwarf::DW_AT_frame_base, Location); + } + } + + // Add name to the name table, we do this here because we're guaranteed + // to have concrete versions of our DW_TAG_subprogram nodes. + DD->addSubprogramNames(*CUNode, SP, *SPDie); + + return *SPDie; +} + +// Construct a DIE for this scope. +void DwarfCompileUnit::constructScopeDIE( + LexicalScope *Scope, SmallVectorImpl<DIE *> &FinalChildren) { + if (!Scope || !Scope->getScopeNode()) + return; + + auto *DS = Scope->getScopeNode(); + + assert((Scope->getInlinedAt() || !isa<DISubprogram>(DS)) && + "Only handle inlined subprograms here, use " + "constructSubprogramScopeDIE for non-inlined " + "subprograms"); + + SmallVector<DIE *, 8> Children; + + // We try to create the scope DIE first, then the children DIEs. This will + // avoid creating un-used children then removing them later when we find out + // the scope DIE is null. + DIE *ScopeDIE; + if (Scope->getParent() && isa<DISubprogram>(DS)) { + ScopeDIE = constructInlinedScopeDIE(Scope); + if (!ScopeDIE) + return; + // We create children when the scope DIE is not null. + createScopeChildrenDIE(Scope, Children); + } else { + // Early exit when we know the scope DIE is going to be null. + if (DD->isLexicalScopeDIENull(Scope)) + return; + + bool HasNonScopeChildren = false; + + // We create children here when we know the scope DIE is not going to be + // null and the children will be added to the scope DIE. + createScopeChildrenDIE(Scope, Children, &HasNonScopeChildren); + + // If there are only other scopes as children, put them directly in the + // parent instead, as this scope would serve no purpose. + if (!HasNonScopeChildren) { + FinalChildren.insert(FinalChildren.end(), + std::make_move_iterator(Children.begin()), + std::make_move_iterator(Children.end())); + return; + } + ScopeDIE = constructLexicalScopeDIE(Scope); + assert(ScopeDIE && "Scope DIE should not be null."); + } + + // Add children + for (auto &I : Children) + ScopeDIE->addChild(std::move(I)); + + FinalChildren.push_back(std::move(ScopeDIE)); +} + +void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE, + SmallVector<RangeSpan, 2> Range) { + + HasRangeLists = true; + + // Add the range list to the set of ranges to be emitted. + auto IndexAndList = + (DD->getDwarfVersion() < 5 && Skeleton ? Skeleton->DU : DU) + ->addRange(*(Skeleton ? Skeleton : this), std::move(Range)); + + uint32_t Index = IndexAndList.first; + auto &List = *IndexAndList.second; + + // Under fission, ranges are specified by constant offsets relative to the + // CU's DW_AT_GNU_ranges_base. + // FIXME: For DWARF v5, do not generate the DW_AT_ranges attribute under + // fission until we support the forms using the .debug_addr section + // (DW_RLE_startx_endx etc.). + if (DD->getDwarfVersion() >= 5) + addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_rnglistx, Index); + else { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + const MCSymbol *RangeSectionSym = + TLOF.getDwarfRangesSection()->getBeginSymbol(); + if (isDwoUnit()) + addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(), + RangeSectionSym); + else + addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(), + RangeSectionSym); + } +} + +void DwarfCompileUnit::attachRangesOrLowHighPC( + DIE &Die, SmallVector<RangeSpan, 2> Ranges) { + if (Ranges.size() == 1 || !DD->useRangesSection()) { + const RangeSpan &Front = Ranges.front(); + const RangeSpan &Back = Ranges.back(); + attachLowHighPC(Die, Front.Begin, Back.End); + } else + addScopeRangeList(Die, std::move(Ranges)); +} + +void DwarfCompileUnit::attachRangesOrLowHighPC( + DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) { + SmallVector<RangeSpan, 2> List; + List.reserve(Ranges.size()); + for (const InsnRange &R : Ranges) + List.push_back( + {DD->getLabelBeforeInsn(R.first), DD->getLabelAfterInsn(R.second)}); + attachRangesOrLowHighPC(Die, std::move(List)); +} + +// This scope represents inlined body of a function. Construct DIE to +// represent this concrete inlined copy of the function. +DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) { + assert(Scope->getScopeNode()); + auto *DS = Scope->getScopeNode(); + auto *InlinedSP = getDISubprogram(DS); + // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram + // was inlined from another compile unit. + DIE *OriginDIE = getAbstractSPDies()[InlinedSP]; + assert(OriginDIE && "Unable to find original DIE for an inlined subprogram."); + + auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_inlined_subroutine); + addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE); + + attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges()); + + // Add the call site information to the DIE. + const DILocation *IA = Scope->getInlinedAt(); + addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None, + getOrCreateSourceID(IA->getFile())); + addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine()); + if (IA->getColumn()) + addUInt(*ScopeDIE, dwarf::DW_AT_call_column, None, IA->getColumn()); + if (IA->getDiscriminator() && DD->getDwarfVersion() >= 4) + addUInt(*ScopeDIE, dwarf::DW_AT_GNU_discriminator, None, + IA->getDiscriminator()); + + // Add name to the name table, we do this here because we're guaranteed + // to have concrete versions of our DW_TAG_inlined_subprogram nodes. + DD->addSubprogramNames(*CUNode, InlinedSP, *ScopeDIE); + + return ScopeDIE; +} + +// Construct new DW_TAG_lexical_block for this scope and attach +// DW_AT_low_pc/DW_AT_high_pc labels. +DIE *DwarfCompileUnit::constructLexicalScopeDIE(LexicalScope *Scope) { + if (DD->isLexicalScopeDIENull(Scope)) + return nullptr; + + auto ScopeDIE = DIE::get(DIEValueAllocator, dwarf::DW_TAG_lexical_block); + if (Scope->isAbstractScope()) + return ScopeDIE; + + attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges()); + + return ScopeDIE; +} + +/// constructVariableDIE - Construct a DIE for the given DbgVariable. +DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, bool Abstract) { + auto D = constructVariableDIEImpl(DV, Abstract); + DV.setDIE(*D); + return D; +} + +DIE *DwarfCompileUnit::constructLabelDIE(DbgLabel &DL, + const LexicalScope &Scope) { + auto LabelDie = DIE::get(DIEValueAllocator, DL.getTag()); + insertDIE(DL.getLabel(), LabelDie); + DL.setDIE(*LabelDie); + + if (Scope.isAbstractScope()) + applyLabelAttributes(DL, *LabelDie); + + return LabelDie; +} + +DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV, + bool Abstract) { + // Define variable debug information entry. + auto VariableDie = DIE::get(DIEValueAllocator, DV.getTag()); + insertDIE(DV.getVariable(), VariableDie); + + if (Abstract) { + applyVariableAttributes(DV, *VariableDie); + return VariableDie; + } + + // Add variable address. + + unsigned Offset = DV.getDebugLocListIndex(); + if (Offset != ~0U) { + addLocationList(*VariableDie, dwarf::DW_AT_location, Offset); + return VariableDie; + } + + // Check if variable has a single location description. + if (auto *DVal = DV.getValueLoc()) { + if (DVal->isLocation()) + addVariableAddress(DV, *VariableDie, DVal->getLoc()); + else if (DVal->isInt()) { + auto *Expr = DV.getSingleExpression(); + if (Expr && Expr->getNumElements()) { + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); + // If there is an expression, emit raw unsigned bytes. + DwarfExpr.addFragmentOffset(Expr); + DwarfExpr.addUnsignedConstant(DVal->getInt()); + DwarfExpr.addExpression(Expr); + addBlock(*VariableDie, dwarf::DW_AT_location, DwarfExpr.finalize()); + } else + addConstantValue(*VariableDie, DVal->getInt(), DV.getType()); + } else if (DVal->isConstantFP()) { + addConstantFPValue(*VariableDie, DVal->getConstantFP()); + } else if (DVal->isConstantInt()) { + addConstantValue(*VariableDie, DVal->getConstantInt(), DV.getType()); + } + return VariableDie; + } + + // .. else use frame index. + if (!DV.hasFrameIndexExprs()) + return VariableDie; + + Optional<unsigned> NVPTXAddressSpace; + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); + for (auto &Fragment : DV.getFrameIndexExprs()) { + unsigned FrameReg = 0; + const DIExpression *Expr = Fragment.Expr; + const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering(); + int Offset = TFI->getFrameIndexReference(*Asm->MF, Fragment.FI, FrameReg); + DwarfExpr.addFragmentOffset(Expr); + SmallVector<uint64_t, 8> Ops; + DIExpression::appendOffset(Ops, Offset); + // According to + // https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf + // cuda-gdb requires DW_AT_address_class for all variables to be able to + // correctly interpret address space of the variable address. + // Decode DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef + // sequence for the NVPTX + gdb target. + unsigned LocalNVPTXAddressSpace; + if (Asm->TM.getTargetTriple().isNVPTX() && DD->tuneForGDB()) { + const DIExpression *NewExpr = + DIExpression::extractAddressClass(Expr, LocalNVPTXAddressSpace); + if (NewExpr != Expr) { + Expr = NewExpr; + NVPTXAddressSpace = LocalNVPTXAddressSpace; + } + } + if (Expr) + Ops.append(Expr->elements_begin(), Expr->elements_end()); + DIExpressionCursor Cursor(Ops); + DwarfExpr.setMemoryLocationKind(); + if (const MCSymbol *FrameSymbol = Asm->getFunctionFrameSymbol()) + addOpAddress(*Loc, FrameSymbol); + else + DwarfExpr.addMachineRegExpression( + *Asm->MF->getSubtarget().getRegisterInfo(), Cursor, FrameReg); + DwarfExpr.addExpression(std::move(Cursor)); + } + if (Asm->TM.getTargetTriple().isNVPTX() && DD->tuneForGDB()) { + // According to + // https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf + // cuda-gdb requires DW_AT_address_class for all variables to be able to + // correctly interpret address space of the variable address. + const unsigned NVPTX_ADDR_local_space = 6; + addUInt(*VariableDie, dwarf::DW_AT_address_class, dwarf::DW_FORM_data1, + NVPTXAddressSpace ? *NVPTXAddressSpace : NVPTX_ADDR_local_space); + } + addBlock(*VariableDie, dwarf::DW_AT_location, DwarfExpr.finalize()); + if (DwarfExpr.TagOffset) + addUInt(*VariableDie, dwarf::DW_AT_LLVM_tag_offset, dwarf::DW_FORM_data1, + *DwarfExpr.TagOffset); + + return VariableDie; +} + +DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV, + const LexicalScope &Scope, + DIE *&ObjectPointer) { + auto Var = constructVariableDIE(DV, Scope.isAbstractScope()); + if (DV.isObjectPointer()) + ObjectPointer = Var; + return Var; +} + +/// Return all DIVariables that appear in count: expressions. +static SmallVector<const DIVariable *, 2> dependencies(DbgVariable *Var) { + SmallVector<const DIVariable *, 2> Result; + auto *Array = dyn_cast<DICompositeType>(Var->getType()); + if (!Array || Array->getTag() != dwarf::DW_TAG_array_type) + return Result; + for (auto *El : Array->getElements()) { + if (auto *Subrange = dyn_cast<DISubrange>(El)) { + auto Count = Subrange->getCount(); + if (auto *Dependency = Count.dyn_cast<DIVariable *>()) + Result.push_back(Dependency); + } + } + return Result; +} + +/// Sort local variables so that variables appearing inside of helper +/// expressions come first. +static SmallVector<DbgVariable *, 8> +sortLocalVars(SmallVectorImpl<DbgVariable *> &Input) { + SmallVector<DbgVariable *, 8> Result; + SmallVector<PointerIntPair<DbgVariable *, 1>, 8> WorkList; + // Map back from a DIVariable to its containing DbgVariable. + SmallDenseMap<const DILocalVariable *, DbgVariable *> DbgVar; + // Set of DbgVariables in Result. + SmallDenseSet<DbgVariable *, 8> Visited; + // For cycle detection. + SmallDenseSet<DbgVariable *, 8> Visiting; + + // Initialize the worklist and the DIVariable lookup table. + for (auto Var : reverse(Input)) { + DbgVar.insert({Var->getVariable(), Var}); + WorkList.push_back({Var, 0}); + } + + // Perform a stable topological sort by doing a DFS. + while (!WorkList.empty()) { + auto Item = WorkList.back(); + DbgVariable *Var = Item.getPointer(); + bool visitedAllDependencies = Item.getInt(); + WorkList.pop_back(); + + // Dependency is in a different lexical scope or a global. + if (!Var) + continue; + + // Already handled. + if (Visited.count(Var)) + continue; + + // Add to Result if all dependencies are visited. + if (visitedAllDependencies) { + Visited.insert(Var); + Result.push_back(Var); + continue; + } + + // Detect cycles. + auto Res = Visiting.insert(Var); + if (!Res.second) { + assert(false && "dependency cycle in local variables"); + return Result; + } + + // Push dependencies and this node onto the worklist, so that this node is + // visited again after all of its dependencies are handled. + WorkList.push_back({Var, 1}); + for (auto *Dependency : dependencies(Var)) { + auto Dep = dyn_cast_or_null<const DILocalVariable>(Dependency); + WorkList.push_back({DbgVar[Dep], 0}); + } + } + return Result; +} + +DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope, + SmallVectorImpl<DIE *> &Children, + bool *HasNonScopeChildren) { + assert(Children.empty()); + DIE *ObjectPointer = nullptr; + + // Emit function arguments (order is significant). + auto Vars = DU->getScopeVariables().lookup(Scope); + for (auto &DV : Vars.Args) + Children.push_back(constructVariableDIE(*DV.second, *Scope, ObjectPointer)); + + // Emit local variables. + auto Locals = sortLocalVars(Vars.Locals); + for (DbgVariable *DV : Locals) + Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer)); + + // Skip imported directives in gmlt-like data. + if (!includeMinimalInlineScopes()) { + // There is no need to emit empty lexical block DIE. + for (const auto *IE : ImportedEntities[Scope->getScopeNode()]) + Children.push_back( + constructImportedEntityDIE(cast<DIImportedEntity>(IE))); + } + + if (HasNonScopeChildren) + *HasNonScopeChildren = !Children.empty(); + + for (DbgLabel *DL : DU->getScopeLabels().lookup(Scope)) + Children.push_back(constructLabelDIE(*DL, *Scope)); + + for (LexicalScope *LS : Scope->getChildren()) + constructScopeDIE(LS, Children); + + return ObjectPointer; +} + +DIE &DwarfCompileUnit::constructSubprogramScopeDIE(const DISubprogram *Sub, + LexicalScope *Scope) { + DIE &ScopeDIE = updateSubprogramScopeDIE(Sub); + + if (Scope) { + assert(!Scope->getInlinedAt()); + assert(!Scope->isAbstractScope()); + // Collect lexical scope children first. + // ObjectPointer might be a local (non-argument) local variable if it's a + // block's synthetic this pointer. + if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE)) + addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer); + } + + // If this is a variadic function, add an unspecified parameter. + DITypeRefArray FnArgs = Sub->getType()->getTypeArray(); + + // If we have a single element of null, it is a function that returns void. + // If we have more than one elements and the last one is null, it is a + // variadic function. + if (FnArgs.size() > 1 && !FnArgs[FnArgs.size() - 1] && + !includeMinimalInlineScopes()) + ScopeDIE.addChild( + DIE::get(DIEValueAllocator, dwarf::DW_TAG_unspecified_parameters)); + + return ScopeDIE; +} + +DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope, + DIE &ScopeDIE) { + // We create children when the scope DIE is not null. + SmallVector<DIE *, 8> Children; + DIE *ObjectPointer = createScopeChildrenDIE(Scope, Children); + + // Add children + for (auto &I : Children) + ScopeDIE.addChild(std::move(I)); + + return ObjectPointer; +} + +void DwarfCompileUnit::constructAbstractSubprogramScopeDIE( + LexicalScope *Scope) { + DIE *&AbsDef = getAbstractSPDies()[Scope->getScopeNode()]; + if (AbsDef) + return; + + auto *SP = cast<DISubprogram>(Scope->getScopeNode()); + + DIE *ContextDIE; + DwarfCompileUnit *ContextCU = this; + + if (includeMinimalInlineScopes()) + ContextDIE = &getUnitDie(); + // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with + // the important distinction that the debug node is not associated with the + // DIE (since the debug node will be associated with the concrete DIE, if + // any). It could be refactored to some common utility function. + else if (auto *SPDecl = SP->getDeclaration()) { + ContextDIE = &getUnitDie(); + getOrCreateSubprogramDIE(SPDecl); + } else { + ContextDIE = getOrCreateContextDIE(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 = &ContextCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, nullptr); + ContextCU->applySubprogramAttributesToDefinition(SP, *AbsDef); + + 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); +} + +/// Whether to use the GNU analog for a DWARF5 tag, attribute, or location atom. +static bool useGNUAnalogForDwarf5Feature(DwarfDebug *DD) { + return DD->getDwarfVersion() == 4 && DD->tuneForGDB(); +} + +dwarf::Tag DwarfCompileUnit::getDwarf5OrGNUTag(dwarf::Tag Tag) const { + if (!useGNUAnalogForDwarf5Feature(DD)) + return Tag; + switch (Tag) { + case dwarf::DW_TAG_call_site: + return dwarf::DW_TAG_GNU_call_site; + case dwarf::DW_TAG_call_site_parameter: + return dwarf::DW_TAG_GNU_call_site_parameter; + default: + llvm_unreachable("DWARF5 tag with no GNU analog"); + } +} + +dwarf::Attribute +DwarfCompileUnit::getDwarf5OrGNUAttr(dwarf::Attribute Attr) const { + if (!useGNUAnalogForDwarf5Feature(DD)) + return Attr; + switch (Attr) { + case dwarf::DW_AT_call_all_calls: + return dwarf::DW_AT_GNU_all_call_sites; + case dwarf::DW_AT_call_target: + return dwarf::DW_AT_GNU_call_site_target; + case dwarf::DW_AT_call_origin: + return dwarf::DW_AT_abstract_origin; + case dwarf::DW_AT_call_pc: + return dwarf::DW_AT_low_pc; + case dwarf::DW_AT_call_value: + return dwarf::DW_AT_GNU_call_site_value; + case dwarf::DW_AT_call_tail_call: + return dwarf::DW_AT_GNU_tail_call; + default: + llvm_unreachable("DWARF5 attribute with no GNU analog"); + } +} + +dwarf::LocationAtom +DwarfCompileUnit::getDwarf5OrGNULocationAtom(dwarf::LocationAtom Loc) const { + if (!useGNUAnalogForDwarf5Feature(DD)) + return Loc; + switch (Loc) { + case dwarf::DW_OP_entry_value: + return dwarf::DW_OP_GNU_entry_value; + default: + llvm_unreachable("DWARF5 location atom with no GNU analog"); + } +} + +DIE &DwarfCompileUnit::constructCallSiteEntryDIE( + DIE &ScopeDIE, const DISubprogram *CalleeSP, bool IsTail, + const MCSymbol *PCAddr, const MCExpr *PCOffset, unsigned CallReg) { + // Insert a call site entry DIE within ScopeDIE. + DIE &CallSiteDIE = createAndAddDIE(getDwarf5OrGNUTag(dwarf::DW_TAG_call_site), + ScopeDIE, nullptr); + + if (CallReg) { + // Indirect call. + addAddress(CallSiteDIE, getDwarf5OrGNUAttr(dwarf::DW_AT_call_target), + MachineLocation(CallReg)); + } else { + DIE *CalleeDIE = getOrCreateSubprogramDIE(CalleeSP); + assert(CalleeDIE && "Could not create DIE for call site entry origin"); + addDIEEntry(CallSiteDIE, getDwarf5OrGNUAttr(dwarf::DW_AT_call_origin), + *CalleeDIE); + } + + if (IsTail) + // Attach DW_AT_call_tail_call to tail calls for standards compliance. + addFlag(CallSiteDIE, getDwarf5OrGNUAttr(dwarf::DW_AT_call_tail_call)); + + // Attach the return PC to allow the debugger to disambiguate call paths + // from one function to another. + if (DD->getDwarfVersion() == 4 && DD->tuneForGDB()) { + assert(PCAddr && "Missing PC information for a call"); + addLabelAddress(CallSiteDIE, dwarf::DW_AT_low_pc, PCAddr); + } else if (!IsTail || DD->tuneForGDB()) { + assert(PCOffset && "Missing return PC information for a call"); + addAddressExpr(CallSiteDIE, dwarf::DW_AT_call_return_pc, PCOffset); + } + + return CallSiteDIE; +} + +void DwarfCompileUnit::constructCallSiteParmEntryDIEs( + DIE &CallSiteDIE, SmallVector<DbgCallSiteParam, 4> &Params) { + for (const auto &Param : Params) { + unsigned Register = Param.getRegister(); + auto CallSiteDieParam = + DIE::get(DIEValueAllocator, + getDwarf5OrGNUTag(dwarf::DW_TAG_call_site_parameter)); + insertDIE(CallSiteDieParam); + addAddress(*CallSiteDieParam, dwarf::DW_AT_location, + MachineLocation(Register)); + + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); + DwarfExpr.setCallSiteParamValueFlag(); + + DwarfDebug::emitDebugLocValue(*Asm, nullptr, Param.getValue(), DwarfExpr); + + addBlock(*CallSiteDieParam, getDwarf5OrGNUAttr(dwarf::DW_AT_call_value), + DwarfExpr.finalize()); + + CallSiteDIE.addChild(CallSiteDieParam); + } +} + +DIE *DwarfCompileUnit::constructImportedEntityDIE( + const DIImportedEntity *Module) { + DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag()); + insertDIE(Module, IMDie); + DIE *EntityDie; + auto *Entity = Module->getEntity(); + if (auto *NS = dyn_cast<DINamespace>(Entity)) + EntityDie = getOrCreateNameSpace(NS); + else if (auto *M = dyn_cast<DIModule>(Entity)) + EntityDie = getOrCreateModule(M); + else if (auto *SP = dyn_cast<DISubprogram>(Entity)) + EntityDie = getOrCreateSubprogramDIE(SP); + else if (auto *T = dyn_cast<DIType>(Entity)) + EntityDie = getOrCreateTypeDIE(T); + else if (auto *GV = dyn_cast<DIGlobalVariable>(Entity)) + EntityDie = getOrCreateGlobalVariableDIE(GV, {}); + else + EntityDie = getDIE(Entity); + assert(EntityDie); + addSourceLine(*IMDie, Module->getLine(), Module->getFile()); + addDIEEntry(*IMDie, dwarf::DW_AT_import, *EntityDie); + StringRef Name = Module->getName(); + if (!Name.empty()) + addString(*IMDie, dwarf::DW_AT_name, Name); + + return IMDie; +} + +void DwarfCompileUnit::finishSubprogramDefinition(const DISubprogram *SP) { + DIE *D = getDIE(SP); + if (DIE *AbsSPDIE = getAbstractSPDies().lookup(SP)) { + if (D) + // If this subprogram has an abstract definition, reference that + addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE); + } else { + assert(D || includeMinimalInlineScopes()); + if (D) + // And attach the attributes + applySubprogramAttributesToDefinition(SP, *D); + } +} + +void DwarfCompileUnit::finishEntityDefinition(const DbgEntity *Entity) { + DbgEntity *AbsEntity = getExistingAbstractEntity(Entity->getEntity()); + + auto *Die = Entity->getDIE(); + /// Label may be used to generate DW_AT_low_pc, so put it outside + /// if/else block. + const DbgLabel *Label = nullptr; + if (AbsEntity && AbsEntity->getDIE()) { + addDIEEntry(*Die, dwarf::DW_AT_abstract_origin, *AbsEntity->getDIE()); + Label = dyn_cast<const DbgLabel>(Entity); + } else { + if (const DbgVariable *Var = dyn_cast<const DbgVariable>(Entity)) + applyVariableAttributes(*Var, *Die); + else if ((Label = dyn_cast<const DbgLabel>(Entity))) + applyLabelAttributes(*Label, *Die); + else + llvm_unreachable("DbgEntity must be DbgVariable or DbgLabel."); + } + + if (Label) + if (const auto *Sym = Label->getSymbol()) + addLabelAddress(*Die, dwarf::DW_AT_low_pc, Sym); +} + +DbgEntity *DwarfCompileUnit::getExistingAbstractEntity(const DINode *Node) { + auto &AbstractEntities = getAbstractEntities(); + auto I = AbstractEntities.find(Node); + if (I != AbstractEntities.end()) + return I->second.get(); + return nullptr; +} + +void DwarfCompileUnit::createAbstractEntity(const DINode *Node, + LexicalScope *Scope) { + assert(Scope && Scope->isAbstractScope()); + auto &Entity = getAbstractEntities()[Node]; + if (isa<const DILocalVariable>(Node)) { + Entity = std::make_unique<DbgVariable>( + cast<const DILocalVariable>(Node), nullptr /* IA */);; + DU->addScopeVariable(Scope, cast<DbgVariable>(Entity.get())); + } else if (isa<const DILabel>(Node)) { + Entity = std::make_unique<DbgLabel>( + cast<const DILabel>(Node), nullptr /* IA */); + DU->addScopeLabel(Scope, cast<DbgLabel>(Entity.get())); + } +} + +void DwarfCompileUnit::emitHeader(bool UseOffsets) { + // Don't bother labeling the .dwo unit, as its offset isn't used. + if (!Skeleton && !DD->useSectionsAsReferences()) { + LabelBegin = Asm->createTempSymbol("cu_begin"); + Asm->OutStreamer->EmitLabel(LabelBegin); + } + + dwarf::UnitType UT = Skeleton ? dwarf::DW_UT_split_compile + : DD->useSplitDwarf() ? dwarf::DW_UT_skeleton + : dwarf::DW_UT_compile; + DwarfUnit::emitCommonHeader(UseOffsets, UT); + if (DD->getDwarfVersion() >= 5 && UT != dwarf::DW_UT_compile) + Asm->emitInt64(getDWOId()); +} + +bool DwarfCompileUnit::hasDwarfPubSections() const { + switch (CUNode->getNameTableKind()) { + case DICompileUnit::DebugNameTableKind::None: + return false; + // Opting in to GNU Pubnames/types overrides the default to ensure these are + // generated for things like Gold's gdb_index generation. + case DICompileUnit::DebugNameTableKind::GNU: + return true; + case DICompileUnit::DebugNameTableKind::Default: + return DD->tuneForGDB() && !includeMinimalInlineScopes() && + !CUNode->isDebugDirectivesOnly() && + DD->getAccelTableKind() != AccelTableKind::Apple && + DD->getDwarfVersion() < 5; + } + llvm_unreachable("Unhandled DICompileUnit::DebugNameTableKind enum"); +} + +/// addGlobalName - Add a new global name to the compile unit. +void DwarfCompileUnit::addGlobalName(StringRef Name, const DIE &Die, + const DIScope *Context) { + if (!hasDwarfPubSections()) + return; + std::string FullName = getParentContextString(Context) + Name.str(); + GlobalNames[FullName] = &Die; +} + +void DwarfCompileUnit::addGlobalNameForTypeUnit(StringRef Name, + const DIScope *Context) { + if (!hasDwarfPubSections()) + return; + std::string FullName = getParentContextString(Context) + Name.str(); + // Insert, allowing the entry to remain as-is if it's already present + // This way the CU-level type DIE is preferred over the "can't describe this + // type as a unit offset because it's not really in the CU at all, it's only + // in a type unit" + GlobalNames.insert(std::make_pair(std::move(FullName), &getUnitDie())); +} + +/// Add a new global type to the unit. +void DwarfCompileUnit::addGlobalType(const DIType *Ty, const DIE &Die, + const DIScope *Context) { + if (!hasDwarfPubSections()) + return; + std::string FullName = getParentContextString(Context) + Ty->getName().str(); + GlobalTypes[FullName] = &Die; +} + +void DwarfCompileUnit::addGlobalTypeUnitType(const DIType *Ty, + const DIScope *Context) { + if (!hasDwarfPubSections()) + return; + std::string FullName = getParentContextString(Context) + Ty->getName().str(); + // Insert, allowing the entry to remain as-is if it's already present + // This way the CU-level type DIE is preferred over the "can't describe this + // type as a unit offset because it's not really in the CU at all, it's only + // in a type unit" + GlobalTypes.insert(std::make_pair(std::move(FullName), &getUnitDie())); +} + +void DwarfCompileUnit::addVariableAddress(const DbgVariable &DV, DIE &Die, + MachineLocation Location) { + if (DV.hasComplexAddress()) + addComplexAddress(DV, Die, dwarf::DW_AT_location, Location); + else + addAddress(Die, dwarf::DW_AT_location, Location); +} + +/// Add an address attribute to a die based on the location provided. +void DwarfCompileUnit::addAddress(DIE &Die, dwarf::Attribute Attribute, + const MachineLocation &Location) { + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); + if (Location.isIndirect()) + DwarfExpr.setMemoryLocationKind(); + + DIExpressionCursor Cursor({}); + const TargetRegisterInfo &TRI = *Asm->MF->getSubtarget().getRegisterInfo(); + if (!DwarfExpr.addMachineRegExpression(TRI, Cursor, Location.getReg())) + return; + DwarfExpr.addExpression(std::move(Cursor)); + + // Now attach the location information to the DIE. + addBlock(Die, Attribute, DwarfExpr.finalize()); +} + +/// Start with the address based on the location provided, and generate the +/// DWARF information necessary to find the actual variable given the extra +/// address information encoded in the DbgVariable, starting from the starting +/// location. Add the DWARF information to the die. +void DwarfCompileUnit::addComplexAddress(const DbgVariable &DV, DIE &Die, + dwarf::Attribute Attribute, + const MachineLocation &Location) { + DIELoc *Loc = new (DIEValueAllocator) DIELoc; + DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); + const DIExpression *DIExpr = DV.getSingleExpression(); + DwarfExpr.addFragmentOffset(DIExpr); + if (Location.isIndirect()) + DwarfExpr.setMemoryLocationKind(); + + DIExpressionCursor Cursor(DIExpr); + + if (DIExpr->isEntryValue()) { + DwarfExpr.setEntryValueFlag(); + DwarfExpr.beginEntryValueExpression(Cursor); + } + + const TargetRegisterInfo &TRI = *Asm->MF->getSubtarget().getRegisterInfo(); + if (!DwarfExpr.addMachineRegExpression(TRI, Cursor, Location.getReg())) + return; + DwarfExpr.addExpression(std::move(Cursor)); + + // Now attach the location information to the DIE. + addBlock(Die, Attribute, DwarfExpr.finalize()); +} + +/// Add a Dwarf loclistptr attribute data and value. +void DwarfCompileUnit::addLocationList(DIE &Die, dwarf::Attribute Attribute, + unsigned Index) { + dwarf::Form Form = DD->getDwarfVersion() >= 4 ? dwarf::DW_FORM_sec_offset + : dwarf::DW_FORM_data4; + Die.addValue(DIEValueAllocator, Attribute, Form, DIELocList(Index)); +} + +void DwarfCompileUnit::applyVariableAttributes(const DbgVariable &Var, + DIE &VariableDie) { + StringRef Name = Var.getName(); + if (!Name.empty()) + addString(VariableDie, dwarf::DW_AT_name, Name); + const auto *DIVar = Var.getVariable(); + if (DIVar) + if (uint32_t AlignInBytes = DIVar->getAlignInBytes()) + addUInt(VariableDie, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata, + AlignInBytes); + + addSourceLine(VariableDie, DIVar); + addType(VariableDie, Var.getType()); + if (Var.isArtificial()) + addFlag(VariableDie, dwarf::DW_AT_artificial); +} + +void DwarfCompileUnit::applyLabelAttributes(const DbgLabel &Label, + DIE &LabelDie) { + StringRef Name = Label.getName(); + if (!Name.empty()) + addString(LabelDie, dwarf::DW_AT_name, Name); + const auto *DILabel = Label.getLabel(); + addSourceLine(LabelDie, DILabel); +} + +/// Add a Dwarf expression attribute data and value. +void DwarfCompileUnit::addExpr(DIELoc &Die, dwarf::Form Form, + const MCExpr *Expr) { + Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, Form, DIEExpr(Expr)); +} + +void DwarfCompileUnit::addAddressExpr(DIE &Die, dwarf::Attribute Attribute, + const MCExpr *Expr) { + Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_addr, + DIEExpr(Expr)); +} + +void DwarfCompileUnit::applySubprogramAttributesToDefinition( + const DISubprogram *SP, DIE &SPDie) { + auto *SPDecl = SP->getDeclaration(); + auto *Context = SPDecl ? SPDecl->getScope() : SP->getScope(); + applySubprogramAttributes(SP, SPDie, includeMinimalInlineScopes()); + addGlobalName(SP->getName(), SPDie, Context); +} + +bool DwarfCompileUnit::isDwoUnit() const { + return DD->useSplitDwarf() && Skeleton; +} + +void DwarfCompileUnit::finishNonUnitTypeDIE(DIE& D, const DICompositeType *CTy) { + constructTypeDIE(D, CTy); +} + +bool DwarfCompileUnit::includeMinimalInlineScopes() const { + return getCUNode()->getEmissionKind() == DICompileUnit::LineTablesOnly || + (DD->useSplitDwarf() && !Skeleton); +} + +void DwarfCompileUnit::addAddrTableBase() { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + MCSymbol *Label = DD->getAddressPool().getLabel(); + addSectionLabel(getUnitDie(), + getDwarfVersion() >= 5 ? dwarf::DW_AT_addr_base + : dwarf::DW_AT_GNU_addr_base, + Label, TLOF.getDwarfAddrSection()->getBeginSymbol()); +} + +void DwarfCompileUnit::addBaseTypeRef(DIEValueList &Die, int64_t Idx) { + Die.addValue(DIEValueAllocator, (dwarf::Attribute)0, dwarf::DW_FORM_udata, + new (DIEValueAllocator) DIEBaseTypeRef(this, Idx)); +} + +void DwarfCompileUnit::createBaseTypeDIEs() { + // Insert the base_type DIEs directly after the CU so that their offsets will + // fit in the fixed size ULEB128 used inside the location expressions. + // Maintain order by iterating backwards and inserting to the front of CU + // child list. + for (auto &Btr : reverse(ExprRefedBaseTypes)) { + DIE &Die = getUnitDie().addChildFront( + DIE::get(DIEValueAllocator, dwarf::DW_TAG_base_type)); + SmallString<32> Str; + addString(Die, dwarf::DW_AT_name, + Twine(dwarf::AttributeEncodingString(Btr.Encoding) + + "_" + Twine(Btr.BitSize)).toStringRef(Str)); + addUInt(Die, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1, Btr.Encoding); + addUInt(Die, dwarf::DW_AT_byte_size, None, Btr.BitSize / 8); + + Btr.Die = &Die; + } +} |