diff options
Diffstat (limited to 'gnu/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp')
| -rw-r--r-- | gnu/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp | 2756 |
1 files changed, 0 insertions, 2756 deletions
diff --git a/gnu/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/gnu/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp deleted file mode 100644 index 18c5fe27b1a..00000000000 --- a/gnu/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ /dev/null @@ -1,2756 +0,0 @@ -//===- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ----------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file contains support for writing dwarf debug info into asm files. -// -//===----------------------------------------------------------------------===// - -#include "DwarfDebug.h" -#include "ByteStreamer.h" -#include "DIEHash.h" -#include "DebugLocEntry.h" -#include "DebugLocStream.h" -#include "DwarfCompileUnit.h" -#include "DwarfExpression.h" -#include "DwarfFile.h" -#include "DwarfUnit.h" -#include "llvm/ADT/APInt.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/DenseSet.h" -#include "llvm/ADT/MapVector.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/StringRef.h" -#include "llvm/ADT/Triple.h" -#include "llvm/ADT/Twine.h" -#include "llvm/BinaryFormat/Dwarf.h" -#include "llvm/CodeGen/AccelTable.h" -#include "llvm/CodeGen/AsmPrinter.h" -#include "llvm/CodeGen/DIE.h" -#include "llvm/CodeGen/LexicalScopes.h" -#include "llvm/CodeGen/MachineBasicBlock.h" -#include "llvm/CodeGen/MachineFunction.h" -#include "llvm/CodeGen/MachineInstr.h" -#include "llvm/CodeGen/MachineModuleInfo.h" -#include "llvm/CodeGen/MachineOperand.h" -#include "llvm/CodeGen/TargetInstrInfo.h" -#include "llvm/CodeGen/TargetRegisterInfo.h" -#include "llvm/CodeGen/TargetSubtargetInfo.h" -#include "llvm/IR/Constants.h" -#include "llvm/IR/DebugInfoMetadata.h" -#include "llvm/IR/DebugLoc.h" -#include "llvm/IR/Function.h" -#include "llvm/IR/GlobalVariable.h" -#include "llvm/IR/Module.h" -#include "llvm/MC/MCAsmInfo.h" -#include "llvm/MC/MCContext.h" -#include "llvm/MC/MCDwarf.h" -#include "llvm/MC/MCSection.h" -#include "llvm/MC/MCStreamer.h" -#include "llvm/MC/MCSymbol.h" -#include "llvm/MC/MCTargetOptions.h" -#include "llvm/MC/MachineLocation.h" -#include "llvm/MC/SectionKind.h" -#include "llvm/Pass.h" -#include "llvm/Support/Casting.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/ErrorHandling.h" -#include "llvm/Support/MD5.h" -#include "llvm/Support/MathExtras.h" -#include "llvm/Support/Timer.h" -#include "llvm/Support/raw_ostream.h" -#include "llvm/Target/TargetLoweringObjectFile.h" -#include "llvm/Target/TargetMachine.h" -#include "llvm/Target/TargetOptions.h" -#include <algorithm> -#include <cassert> -#include <cstddef> -#include <cstdint> -#include <iterator> -#include <string> -#include <utility> -#include <vector> - -using namespace llvm; - -#define DEBUG_TYPE "dwarfdebug" - -static cl::opt<bool> -DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, - cl::desc("Disable debug info printing")); - -static cl::opt<bool> UseDwarfRangesBaseAddressSpecifier( - "use-dwarf-ranges-base-address-specifier", cl::Hidden, - cl::desc("Use base address specifiers in debug_ranges"), cl::init(false)); - -static cl::opt<bool> GenerateARangeSection("generate-arange-section", - cl::Hidden, - cl::desc("Generate dwarf aranges"), - cl::init(false)); - -static cl::opt<bool> - GenerateDwarfTypeUnits("generate-type-units", cl::Hidden, - cl::desc("Generate DWARF4 type units."), - cl::init(false)); - -static cl::opt<bool> SplitDwarfCrossCuReferences( - "split-dwarf-cross-cu-references", cl::Hidden, - cl::desc("Enable cross-cu references in DWO files"), cl::init(false)); - -enum DefaultOnOff { Default, Enable, Disable }; - -static cl::opt<DefaultOnOff> UnknownLocations( - "use-unknown-locations", cl::Hidden, - cl::desc("Make an absence of debug location information explicit."), - cl::values(clEnumVal(Default, "At top of block or after label"), - clEnumVal(Enable, "In all cases"), clEnumVal(Disable, "Never")), - cl::init(Default)); - -static cl::opt<AccelTableKind> AccelTables( - "accel-tables", cl::Hidden, cl::desc("Output dwarf accelerator tables."), - cl::values(clEnumValN(AccelTableKind::Default, "Default", - "Default for platform"), - clEnumValN(AccelTableKind::None, "Disable", "Disabled."), - clEnumValN(AccelTableKind::Apple, "Apple", "Apple"), - clEnumValN(AccelTableKind::Dwarf, "Dwarf", "DWARF")), - cl::init(AccelTableKind::Default)); - -static cl::opt<DefaultOnOff> -DwarfInlinedStrings("dwarf-inlined-strings", cl::Hidden, - cl::desc("Use inlined strings rather than string section."), - cl::values(clEnumVal(Default, "Default for platform"), - clEnumVal(Enable, "Enabled"), - clEnumVal(Disable, "Disabled")), - cl::init(Default)); - -static cl::opt<bool> - NoDwarfRangesSection("no-dwarf-ranges-section", cl::Hidden, - cl::desc("Disable emission .debug_ranges section."), - cl::init(false)); - -static cl::opt<DefaultOnOff> DwarfSectionsAsReferences( - "dwarf-sections-as-references", cl::Hidden, - cl::desc("Use sections+offset as references rather than labels."), - cl::values(clEnumVal(Default, "Default for platform"), - clEnumVal(Enable, "Enabled"), clEnumVal(Disable, "Disabled")), - cl::init(Default)); - -enum LinkageNameOption { - DefaultLinkageNames, - AllLinkageNames, - AbstractLinkageNames -}; - -static cl::opt<LinkageNameOption> - DwarfLinkageNames("dwarf-linkage-names", cl::Hidden, - cl::desc("Which DWARF linkage-name attributes to emit."), - cl::values(clEnumValN(DefaultLinkageNames, "Default", - "Default for platform"), - clEnumValN(AllLinkageNames, "All", "All"), - clEnumValN(AbstractLinkageNames, "Abstract", - "Abstract subprograms")), - cl::init(DefaultLinkageNames)); - -static const char *const DWARFGroupName = "dwarf"; -static const char *const DWARFGroupDescription = "DWARF Emission"; -static const char *const DbgTimerName = "writer"; -static const char *const DbgTimerDescription = "DWARF Debug Writer"; - -void DebugLocDwarfExpression::emitOp(uint8_t Op, const char *Comment) { - BS.EmitInt8( - Op, Comment ? Twine(Comment) + " " + dwarf::OperationEncodingString(Op) - : dwarf::OperationEncodingString(Op)); -} - -void DebugLocDwarfExpression::emitSigned(int64_t Value) { - BS.EmitSLEB128(Value, Twine(Value)); -} - -void DebugLocDwarfExpression::emitUnsigned(uint64_t Value) { - BS.EmitULEB128(Value, Twine(Value)); -} - -bool DebugLocDwarfExpression::isFrameRegister(const TargetRegisterInfo &TRI, - unsigned MachineReg) { - // This information is not available while emitting .debug_loc entries. - return false; -} - -bool DbgVariable::isBlockByrefVariable() const { - assert(getVariable() && "Invalid complex DbgVariable!"); - return getVariable()->getType().resolve()->isBlockByrefStruct(); -} - -const DIType *DbgVariable::getType() const { - DIType *Ty = getVariable()->getType().resolve(); - // FIXME: isBlockByrefVariable should be reformulated in terms of complex - // addresses instead. - if (Ty->isBlockByrefStruct()) { - /* Byref variables, in Blocks, are declared by the programmer as - "SomeType VarName;", but the compiler creates a - __Block_byref_x_VarName struct, and gives the variable VarName - either the struct, or a pointer to the struct, as its type. This - is necessary for various behind-the-scenes things the compiler - needs to do with by-reference variables in blocks. - - However, as far as the original *programmer* is concerned, the - variable should still have type 'SomeType', as originally declared. - - The following function dives into the __Block_byref_x_VarName - struct to find the original type of the variable. This will be - passed back to the code generating the type for the Debug - Information Entry for the variable 'VarName'. 'VarName' will then - have the original type 'SomeType' in its debug information. - - The original type 'SomeType' will be the type of the field named - 'VarName' inside the __Block_byref_x_VarName struct. - - NOTE: In order for this to not completely fail on the debugger - side, the Debug Information Entry for the variable VarName needs to - have a DW_AT_location that tells the debugger how to unwind through - the pointers and __Block_byref_x_VarName struct to find the actual - value of the variable. The function addBlockByrefType does this. */ - DIType *subType = Ty; - uint16_t tag = Ty->getTag(); - - if (tag == dwarf::DW_TAG_pointer_type) - subType = resolve(cast<DIDerivedType>(Ty)->getBaseType()); - - auto Elements = cast<DICompositeType>(subType)->getElements(); - for (unsigned i = 0, N = Elements.size(); i < N; ++i) { - auto *DT = cast<DIDerivedType>(Elements[i]); - if (getName() == DT->getName()) - return resolve(DT->getBaseType()); - } - } - return Ty; -} - -ArrayRef<DbgVariable::FrameIndexExpr> DbgVariable::getFrameIndexExprs() const { - if (FrameIndexExprs.size() == 1) - return FrameIndexExprs; - - assert(llvm::all_of(FrameIndexExprs, - [](const FrameIndexExpr &A) { - return A.Expr->isFragment(); - }) && - "multiple FI expressions without DW_OP_LLVM_fragment"); - llvm::sort(FrameIndexExprs, - [](const FrameIndexExpr &A, const FrameIndexExpr &B) -> bool { - return A.Expr->getFragmentInfo()->OffsetInBits < - B.Expr->getFragmentInfo()->OffsetInBits; - }); - - return FrameIndexExprs; -} - -void DbgVariable::addMMIEntry(const DbgVariable &V) { - assert(DebugLocListIndex == ~0U && !MInsn && "not an MMI entry"); - assert(V.DebugLocListIndex == ~0U && !V.MInsn && "not an MMI entry"); - assert(V.getVariable() == getVariable() && "conflicting variable"); - assert(V.getInlinedAt() == getInlinedAt() && "conflicting inlined-at location"); - - assert(!FrameIndexExprs.empty() && "Expected an MMI entry"); - assert(!V.FrameIndexExprs.empty() && "Expected an MMI entry"); - - // FIXME: This logic should not be necessary anymore, as we now have proper - // deduplication. However, without it, we currently run into the assertion - // below, which means that we are likely dealing with broken input, i.e. two - // non-fragment entries for the same variable at different frame indices. - if (FrameIndexExprs.size()) { - auto *Expr = FrameIndexExprs.back().Expr; - if (!Expr || !Expr->isFragment()) - return; - } - - for (const auto &FIE : V.FrameIndexExprs) - // Ignore duplicate entries. - if (llvm::none_of(FrameIndexExprs, [&](const FrameIndexExpr &Other) { - return FIE.FI == Other.FI && FIE.Expr == Other.Expr; - })) - FrameIndexExprs.push_back(FIE); - - assert((FrameIndexExprs.size() == 1 || - llvm::all_of(FrameIndexExprs, - [](FrameIndexExpr &FIE) { - return FIE.Expr && FIE.Expr->isFragment(); - })) && - "conflicting locations for variable"); -} - -static AccelTableKind computeAccelTableKind(unsigned DwarfVersion, - bool GenerateTypeUnits, - DebuggerKind Tuning, - const Triple &TT) { - // Honor an explicit request. - if (AccelTables != AccelTableKind::Default) - return AccelTables; - - // Accelerator tables with type units are currently not supported. - if (GenerateTypeUnits) - return AccelTableKind::None; - - // Accelerator tables get emitted if targetting DWARF v5 or LLDB. DWARF v5 - // always implies debug_names. For lower standard versions we use apple - // accelerator tables on apple platforms and debug_names elsewhere. - if (DwarfVersion >= 5) - return AccelTableKind::Dwarf; - if (Tuning == DebuggerKind::LLDB) - return TT.isOSBinFormatMachO() ? AccelTableKind::Apple - : AccelTableKind::Dwarf; - return AccelTableKind::None; -} - -DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) - : DebugHandlerBase(A), DebugLocs(A->OutStreamer->isVerboseAsm()), - InfoHolder(A, "info_string", DIEValueAllocator), - SkeletonHolder(A, "skel_string", DIEValueAllocator), - IsDarwin(A->TM.getTargetTriple().isOSDarwin()) { - const Triple &TT = Asm->TM.getTargetTriple(); - - // Make sure we know our "debugger tuning." The target option takes - // precedence; fall back to triple-based defaults. - if (Asm->TM.Options.DebuggerTuning != DebuggerKind::Default) - DebuggerTuning = Asm->TM.Options.DebuggerTuning; - else if (IsDarwin) - DebuggerTuning = DebuggerKind::LLDB; - else if (TT.isPS4CPU()) - DebuggerTuning = DebuggerKind::SCE; - else - DebuggerTuning = DebuggerKind::GDB; - - if (DwarfInlinedStrings == Default) - UseInlineStrings = TT.isNVPTX(); - else - UseInlineStrings = DwarfInlinedStrings == Enable; - - UseLocSection = !TT.isNVPTX(); - - HasAppleExtensionAttributes = tuneForLLDB(); - - // Handle split DWARF. - HasSplitDwarf = !Asm->TM.Options.MCOptions.SplitDwarfFile.empty(); - - // SCE defaults to linkage names only for abstract subprograms. - if (DwarfLinkageNames == DefaultLinkageNames) - UseAllLinkageNames = !tuneForSCE(); - else - UseAllLinkageNames = DwarfLinkageNames == AllLinkageNames; - - unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion; - unsigned DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber - : MMI->getModule()->getDwarfVersion(); - // Use dwarf 4 by default if nothing is requested. For NVPTX, use dwarf 2. - DwarfVersion = - TT.isNVPTX() ? 2 : (DwarfVersion ? DwarfVersion : dwarf::DWARF_VERSION); - - UseRangesSection = !NoDwarfRangesSection && !TT.isNVPTX(); - - // Use sections as references. Force for NVPTX. - if (DwarfSectionsAsReferences == Default) - UseSectionsAsReferences = TT.isNVPTX(); - else - UseSectionsAsReferences = DwarfSectionsAsReferences == Enable; - - // Don't generate type units for unsupported object file formats. - GenerateTypeUnits = - A->TM.getTargetTriple().isOSBinFormatELF() && GenerateDwarfTypeUnits; - - TheAccelTableKind = computeAccelTableKind( - DwarfVersion, GenerateTypeUnits, DebuggerTuning, A->TM.getTargetTriple()); - - // Work around a GDB bug. GDB doesn't support the standard opcode; - // SCE doesn't support GNU's; LLDB prefers the standard opcode, which - // is defined as of DWARF 3. - // See GDB bug 11616 - DW_OP_form_tls_address is unimplemented - // https://sourceware.org/bugzilla/show_bug.cgi?id=11616 - UseGNUTLSOpcode = tuneForGDB() || DwarfVersion < 3; - - // GDB does not fully support the DWARF 4 representation for bitfields. - UseDWARF2Bitfields = (DwarfVersion < 4) || tuneForGDB(); - - // The DWARF v5 string offsets table has - possibly shared - contributions - // from each compile and type unit each preceded by a header. The string - // offsets table used by the pre-DWARF v5 split-DWARF implementation uses - // a monolithic string offsets table without any header. - UseSegmentedStringOffsetsTable = DwarfVersion >= 5; - - Asm->OutStreamer->getContext().setDwarfVersion(DwarfVersion); -} - -// Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h. -DwarfDebug::~DwarfDebug() = default; - -static bool isObjCClass(StringRef Name) { - return Name.startswith("+") || Name.startswith("-"); -} - -static bool hasObjCCategory(StringRef Name) { - if (!isObjCClass(Name)) - return false; - - return Name.find(") ") != StringRef::npos; -} - -static void getObjCClassCategory(StringRef In, StringRef &Class, - StringRef &Category) { - if (!hasObjCCategory(In)) { - Class = In.slice(In.find('[') + 1, In.find(' ')); - Category = ""; - return; - } - - Class = In.slice(In.find('[') + 1, In.find('(')); - Category = In.slice(In.find('[') + 1, In.find(' ')); -} - -static StringRef getObjCMethodName(StringRef In) { - return In.slice(In.find(' ') + 1, In.find(']')); -} - -// Add the various names to the Dwarf accelerator table names. -void DwarfDebug::addSubprogramNames(const DICompileUnit &CU, - const DISubprogram *SP, DIE &Die) { - if (getAccelTableKind() != AccelTableKind::Apple && - CU.getNameTableKind() == DICompileUnit::DebugNameTableKind::None) - return; - - if (!SP->isDefinition()) - return; - - if (SP->getName() != "") - addAccelName(CU, SP->getName(), Die); - - // If the linkage name is different than the name, go ahead and output that as - // well into the name table. Only do that if we are going to actually emit - // that name. - if (SP->getLinkageName() != "" && SP->getName() != SP->getLinkageName() && - (useAllLinkageNames() || InfoHolder.getAbstractSPDies().lookup(SP))) - addAccelName(CU, SP->getLinkageName(), Die); - - // If this is an Objective-C selector name add it to the ObjC accelerator - // too. - if (isObjCClass(SP->getName())) { - StringRef Class, Category; - getObjCClassCategory(SP->getName(), Class, Category); - addAccelObjC(CU, Class, Die); - if (Category != "") - addAccelObjC(CU, Category, Die); - // Also add the base method name to the name table. - addAccelName(CU, getObjCMethodName(SP->getName()), Die); - } -} - -/// Check whether we should create a DIE for the given Scope, return true -/// if we don't create a DIE (the corresponding DIE is null). -bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { - if (Scope->isAbstractScope()) - return false; - - // We don't create a DIE if there is no Range. - const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); - if (Ranges.empty()) - return true; - - if (Ranges.size() > 1) - return false; - - // We don't create a DIE if we have a single Range and the end label - // is null. - return !getLabelAfterInsn(Ranges.front().second); -} - -template <typename Func> static void forBothCUs(DwarfCompileUnit &CU, Func F) { - F(CU); - if (auto *SkelCU = CU.getSkeleton()) - if (CU.getCUNode()->getSplitDebugInlining()) - F(*SkelCU); -} - -bool DwarfDebug::shareAcrossDWOCUs() const { - return SplitDwarfCrossCuReferences; -} - -void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &SrcCU, - LexicalScope *Scope) { - assert(Scope && Scope->getScopeNode()); - assert(Scope->isAbstractScope()); - assert(!Scope->getInlinedAt()); - - auto *SP = cast<DISubprogram>(Scope->getScopeNode()); - - // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram - // was inlined from another compile unit. - if (useSplitDwarf() && !shareAcrossDWOCUs() && !SP->getUnit()->getSplitDebugInlining()) - // Avoid building the original CU if it won't be used - SrcCU.constructAbstractSubprogramScopeDIE(Scope); - else { - auto &CU = getOrCreateDwarfCompileUnit(SP->getUnit()); - if (auto *SkelCU = CU.getSkeleton()) { - (shareAcrossDWOCUs() ? CU : SrcCU) - .constructAbstractSubprogramScopeDIE(Scope); - if (CU.getCUNode()->getSplitDebugInlining()) - SkelCU->constructAbstractSubprogramScopeDIE(Scope); - } else - CU.constructAbstractSubprogramScopeDIE(Scope); - } -} - -void DwarfDebug::constructCallSiteEntryDIEs(const DISubprogram &SP, - DwarfCompileUnit &CU, DIE &ScopeDIE, - const MachineFunction &MF) { - // Add a call site-related attribute (DWARF5, Sec. 3.3.1.3). Do this only if - // the subprogram is required to have one. - if (!SP.areAllCallsDescribed() || !SP.isDefinition()) - return; - - // Use DW_AT_call_all_calls to express that call site entries are present - // for both tail and non-tail calls. Don't use DW_AT_call_all_source_calls - // because one of its requirements is not met: call site entries for - // optimized-out calls are elided. - CU.addFlag(ScopeDIE, dwarf::DW_AT_call_all_calls); - - const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo(); - assert(TII && "TargetInstrInfo not found: cannot label tail calls"); - - // Emit call site entries for each call or tail call in the function. - for (const MachineBasicBlock &MBB : MF) { - for (const MachineInstr &MI : MBB.instrs()) { - // Skip instructions which aren't calls. Both calls and tail-calling jump - // instructions (e.g TAILJMPd64) are classified correctly here. - if (!MI.isCall()) - continue; - - // TODO: Add support for targets with delay slots (see: beginInstruction). - if (MI.hasDelaySlot()) - return; - - // If this is a direct call, find the callee's subprogram. - const MachineOperand &CalleeOp = MI.getOperand(0); - if (!CalleeOp.isGlobal()) - continue; - const Function *CalleeDecl = dyn_cast<Function>(CalleeOp.getGlobal()); - if (!CalleeDecl || !CalleeDecl->getSubprogram()) - continue; - - // TODO: Omit call site entries for runtime calls (objc_msgSend, etc). - // TODO: Add support for indirect calls. - - bool IsTail = TII->isTailCall(MI); - - // For tail calls, no return PC information is needed. For regular calls, - // the return PC is needed to disambiguate paths in the call graph which - // could lead to some target function. - const MCExpr *PCOffset = - IsTail ? nullptr : getFunctionLocalOffsetAfterInsn(&MI); - - assert((IsTail || PCOffset) && "Call without return PC information"); - LLVM_DEBUG(dbgs() << "CallSiteEntry: " << MF.getName() << " -> " - << CalleeDecl->getName() << (IsTail ? " [tail]" : "") - << "\n"); - CU.constructCallSiteEntryDIE(ScopeDIE, *CalleeDecl->getSubprogram(), - IsTail, PCOffset); - } - } -} - -void DwarfDebug::addGnuPubAttributes(DwarfCompileUnit &U, DIE &D) const { - if (!U.hasDwarfPubSections()) - return; - - U.addFlag(D, dwarf::DW_AT_GNU_pubnames); -} - -void DwarfDebug::finishUnitAttributes(const DICompileUnit *DIUnit, - DwarfCompileUnit &NewCU) { - DIE &Die = NewCU.getUnitDie(); - StringRef FN = DIUnit->getFilename(); - - StringRef Producer = DIUnit->getProducer(); - StringRef Flags = DIUnit->getFlags(); - if (!Flags.empty() && !useAppleExtensionAttributes()) { - std::string ProducerWithFlags = Producer.str() + " " + Flags.str(); - NewCU.addString(Die, dwarf::DW_AT_producer, ProducerWithFlags); - } else - NewCU.addString(Die, dwarf::DW_AT_producer, Producer); - - NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, - DIUnit->getSourceLanguage()); - NewCU.addString(Die, dwarf::DW_AT_name, FN); - - // Add DW_str_offsets_base to the unit DIE, except for split units. - if (useSegmentedStringOffsetsTable() && !useSplitDwarf()) - NewCU.addStringOffsetsStart(); - - if (!useSplitDwarf()) { - NewCU.initStmtList(); - - // If we're using split dwarf the compilation dir is going to be in the - // skeleton CU and so we don't need to duplicate it here. - if (!CompilationDir.empty()) - NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); - - addGnuPubAttributes(NewCU, Die); - } - - if (useAppleExtensionAttributes()) { - if (DIUnit->isOptimized()) - NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized); - - StringRef Flags = DIUnit->getFlags(); - if (!Flags.empty()) - NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags); - - if (unsigned RVer = DIUnit->getRuntimeVersion()) - NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, - dwarf::DW_FORM_data1, RVer); - } - - if (DIUnit->getDWOId()) { - // This CU is either a clang module DWO or a skeleton CU. - NewCU.addUInt(Die, dwarf::DW_AT_GNU_dwo_id, dwarf::DW_FORM_data8, - DIUnit->getDWOId()); - if (!DIUnit->getSplitDebugFilename().empty()) - // This is a prefabricated skeleton CU. - NewCU.addString(Die, dwarf::DW_AT_GNU_dwo_name, - DIUnit->getSplitDebugFilename()); - } -} -// Create new DwarfCompileUnit for the given metadata node with tag -// DW_TAG_compile_unit. -DwarfCompileUnit & -DwarfDebug::getOrCreateDwarfCompileUnit(const DICompileUnit *DIUnit) { - if (auto *CU = CUMap.lookup(DIUnit)) - return *CU; - - CompilationDir = DIUnit->getDirectory(); - - auto OwnedUnit = llvm::make_unique<DwarfCompileUnit>( - InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder); - DwarfCompileUnit &NewCU = *OwnedUnit; - InfoHolder.addUnit(std::move(OwnedUnit)); - - for (auto *IE : DIUnit->getImportedEntities()) - NewCU.addImportedEntity(IE); - - // LTO with assembly output shares a single line table amongst multiple CUs. - // To avoid the compilation directory being ambiguous, let the line table - // explicitly describe the directory of all files, never relying on the - // compilation directory. - if (!Asm->OutStreamer->hasRawTextSupport() || SingleCU) - Asm->OutStreamer->emitDwarfFile0Directive( - CompilationDir, DIUnit->getFilename(), - NewCU.getMD5AsBytes(DIUnit->getFile()), DIUnit->getSource(), - NewCU.getUniqueID()); - - if (useSplitDwarf()) { - NewCU.setSkeleton(constructSkeletonCU(NewCU)); - NewCU.setSection(Asm->getObjFileLowering().getDwarfInfoDWOSection()); - } else { - finishUnitAttributes(DIUnit, NewCU); - NewCU.setSection(Asm->getObjFileLowering().getDwarfInfoSection()); - } - - CUMap.insert({DIUnit, &NewCU}); - CUDieMap.insert({&NewCU.getUnitDie(), &NewCU}); - return NewCU; -} - -void DwarfDebug::constructAndAddImportedEntityDIE(DwarfCompileUnit &TheCU, - const DIImportedEntity *N) { - if (isa<DILocalScope>(N->getScope())) - return; - if (DIE *D = TheCU.getOrCreateContextDIE(N->getScope())) - D->addChild(TheCU.constructImportedEntityDIE(N)); -} - -/// Sort and unique GVEs by comparing their fragment offset. -static SmallVectorImpl<DwarfCompileUnit::GlobalExpr> & -sortGlobalExprs(SmallVectorImpl<DwarfCompileUnit::GlobalExpr> &GVEs) { - llvm::sort( - GVEs, [](DwarfCompileUnit::GlobalExpr A, DwarfCompileUnit::GlobalExpr B) { - // Sort order: first null exprs, then exprs without fragment - // info, then sort by fragment offset in bits. - // FIXME: Come up with a more comprehensive comparator so - // the sorting isn't non-deterministic, and so the following - // std::unique call works correctly. - if (!A.Expr || !B.Expr) - return !!B.Expr; - auto FragmentA = A.Expr->getFragmentInfo(); - auto FragmentB = B.Expr->getFragmentInfo(); - if (!FragmentA || !FragmentB) - return !!FragmentB; - return FragmentA->OffsetInBits < FragmentB->OffsetInBits; - }); - GVEs.erase(std::unique(GVEs.begin(), GVEs.end(), - [](DwarfCompileUnit::GlobalExpr A, - DwarfCompileUnit::GlobalExpr B) { - return A.Expr == B.Expr; - }), - GVEs.end()); - return GVEs; -} - -// Emit all Dwarf sections that should come prior to the content. Create -// global DIEs and emit initial debug info sections. This is invoked by -// the target AsmPrinter. -void DwarfDebug::beginModule() { - NamedRegionTimer T(DbgTimerName, DbgTimerDescription, DWARFGroupName, - DWARFGroupDescription, TimePassesIsEnabled); - if (DisableDebugInfoPrinting) { - MMI->setDebugInfoAvailability(false); - return; - } - - const Module *M = MMI->getModule(); - - unsigned NumDebugCUs = std::distance(M->debug_compile_units_begin(), - M->debug_compile_units_end()); - // Tell MMI whether we have debug info. - assert(MMI->hasDebugInfo() == (NumDebugCUs > 0) && - "DebugInfoAvailabilty initialized unexpectedly"); - SingleCU = NumDebugCUs == 1; - DenseMap<DIGlobalVariable *, SmallVector<DwarfCompileUnit::GlobalExpr, 1>> - GVMap; - for (const GlobalVariable &Global : M->globals()) { - SmallVector<DIGlobalVariableExpression *, 1> GVs; - Global.getDebugInfo(GVs); - for (auto *GVE : GVs) - GVMap[GVE->getVariable()].push_back({&Global, GVE->getExpression()}); - } - - // Create the symbol that designates the start of the unit's contribution - // to the string offsets table. In a split DWARF scenario, only the skeleton - // unit has the DW_AT_str_offsets_base attribute (and hence needs the symbol). - if (useSegmentedStringOffsetsTable()) - (useSplitDwarf() ? SkeletonHolder : InfoHolder) - .setStringOffsetsStartSym(Asm->createTempSymbol("str_offsets_base")); - - - // Create the symbols that designates the start of the DWARF v5 range list - // and locations list tables. They are located past the table headers. - if (getDwarfVersion() >= 5) { - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - Holder.setRnglistsTableBaseSym( - Asm->createTempSymbol("rnglists_table_base")); - Holder.setLoclistsTableBaseSym( - Asm->createTempSymbol("loclists_table_base")); - - if (useSplitDwarf()) - InfoHolder.setRnglistsTableBaseSym( - Asm->createTempSymbol("rnglists_dwo_table_base")); - } - - // Create the symbol that points to the first entry following the debug - // address table (.debug_addr) header. - AddrPool.setLabel(Asm->createTempSymbol("addr_table_base")); - - for (DICompileUnit *CUNode : M->debug_compile_units()) { - // FIXME: Move local imported entities into a list attached to the - // subprogram, then this search won't be needed and a - // getImportedEntities().empty() test should go below with the rest. - bool HasNonLocalImportedEntities = llvm::any_of( - CUNode->getImportedEntities(), [](const DIImportedEntity *IE) { - return !isa<DILocalScope>(IE->getScope()); - }); - - if (!HasNonLocalImportedEntities && CUNode->getEnumTypes().empty() && - CUNode->getRetainedTypes().empty() && - CUNode->getGlobalVariables().empty() && CUNode->getMacros().empty()) - continue; - - DwarfCompileUnit &CU = getOrCreateDwarfCompileUnit(CUNode); - - // Global Variables. - for (auto *GVE : CUNode->getGlobalVariables()) { - // Don't bother adding DIGlobalVariableExpressions listed in the CU if we - // already know about the variable and it isn't adding a constant - // expression. - auto &GVMapEntry = GVMap[GVE->getVariable()]; - auto *Expr = GVE->getExpression(); - if (!GVMapEntry.size() || (Expr && Expr->isConstant())) - GVMapEntry.push_back({nullptr, Expr}); - } - DenseSet<DIGlobalVariable *> Processed; - for (auto *GVE : CUNode->getGlobalVariables()) { - DIGlobalVariable *GV = GVE->getVariable(); - if (Processed.insert(GV).second) - CU.getOrCreateGlobalVariableDIE(GV, sortGlobalExprs(GVMap[GV])); - } - - for (auto *Ty : CUNode->getEnumTypes()) { - // The enum types array by design contains pointers to - // MDNodes rather than DIRefs. Unique them here. - CU.getOrCreateTypeDIE(cast<DIType>(Ty)); - } - for (auto *Ty : CUNode->getRetainedTypes()) { - // The retained types array by design contains pointers to - // MDNodes rather than DIRefs. Unique them here. - if (DIType *RT = dyn_cast<DIType>(Ty)) - // There is no point in force-emitting a forward declaration. - CU.getOrCreateTypeDIE(RT); - } - // Emit imported_modules last so that the relevant context is already - // available. - for (auto *IE : CUNode->getImportedEntities()) - constructAndAddImportedEntityDIE(CU, IE); - } -} - -void DwarfDebug::finishEntityDefinitions() { - for (const auto &Entity : ConcreteEntities) { - DIE *Die = Entity->getDIE(); - assert(Die); - // FIXME: Consider the time-space tradeoff of just storing the unit pointer - // in the ConcreteEntities list, rather than looking it up again here. - // DIE::getUnit isn't simple - it walks parent pointers, etc. - DwarfCompileUnit *Unit = CUDieMap.lookup(Die->getUnitDie()); - assert(Unit); - Unit->finishEntityDefinition(Entity.get()); - } -} - -void DwarfDebug::finishSubprogramDefinitions() { - for (const DISubprogram *SP : ProcessedSPNodes) { - assert(SP->getUnit()->getEmissionKind() != DICompileUnit::NoDebug); - forBothCUs( - getOrCreateDwarfCompileUnit(SP->getUnit()), - [&](DwarfCompileUnit &CU) { CU.finishSubprogramDefinition(SP); }); - } -} - -void DwarfDebug::finalizeModuleInfo() { - const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); - - finishSubprogramDefinitions(); - - finishEntityDefinitions(); - - // Include the DWO file name in the hash if there's more than one CU. - // This handles ThinLTO's situation where imported CUs may very easily be - // duplicate with the same CU partially imported into another ThinLTO unit. - StringRef DWOName; - if (CUMap.size() > 1) - DWOName = Asm->TM.Options.MCOptions.SplitDwarfFile; - - // Handle anything that needs to be done on a per-unit basis after - // all other generation. - for (const auto &P : CUMap) { - auto &TheCU = *P.second; - if (TheCU.getCUNode()->isDebugDirectivesOnly()) - continue; - // Emit DW_AT_containing_type attribute to connect types with their - // vtable holding type. - TheCU.constructContainingTypeDIEs(); - - // Add CU specific attributes if we need to add any. - // If we're splitting the dwarf out now that we've got the entire - // CU then add the dwo id to it. - auto *SkCU = TheCU.getSkeleton(); - if (useSplitDwarf() && !empty(TheCU.getUnitDie().children())) { - finishUnitAttributes(TheCU.getCUNode(), TheCU); - TheCU.addString(TheCU.getUnitDie(), dwarf::DW_AT_GNU_dwo_name, - Asm->TM.Options.MCOptions.SplitDwarfFile); - SkCU->addString(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_name, - Asm->TM.Options.MCOptions.SplitDwarfFile); - // Emit a unique identifier for this CU. - uint64_t ID = - DIEHash(Asm).computeCUSignature(DWOName, TheCU.getUnitDie()); - if (getDwarfVersion() >= 5) { - TheCU.setDWOId(ID); - SkCU->setDWOId(ID); - } else { - TheCU.addUInt(TheCU.getUnitDie(), dwarf::DW_AT_GNU_dwo_id, - dwarf::DW_FORM_data8, ID); - SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id, - dwarf::DW_FORM_data8, ID); - } - - if (getDwarfVersion() < 5 && !SkeletonHolder.getRangeLists().empty()) { - const MCSymbol *Sym = TLOF.getDwarfRangesSection()->getBeginSymbol(); - SkCU->addSectionLabel(SkCU->getUnitDie(), dwarf::DW_AT_GNU_ranges_base, - Sym, Sym); - } - } else if (SkCU) { - finishUnitAttributes(SkCU->getCUNode(), *SkCU); - } - - // If we have code split among multiple sections or non-contiguous - // ranges of code then emit a DW_AT_ranges attribute on the unit that will - // remain in the .o file, otherwise add a DW_AT_low_pc. - // FIXME: We should use ranges allow reordering of code ala - // .subsections_via_symbols in mach-o. This would mean turning on - // ranges for all subprogram DIEs for mach-o. - DwarfCompileUnit &U = SkCU ? *SkCU : TheCU; - - // We don't keep track of which addresses are used in which CU so this - // is a bit pessimistic under LTO. - if (!AddrPool.isEmpty() && - (getDwarfVersion() >= 5 || - (SkCU && !empty(TheCU.getUnitDie().children())))) - U.addAddrTableBase(); - - if (unsigned NumRanges = TheCU.getRanges().size()) { - if (NumRanges > 1 && useRangesSection()) - // A DW_AT_low_pc attribute may also be specified in combination with - // DW_AT_ranges to specify the default base address for use in - // location lists (see Section 2.6.2) and range lists (see Section - // 2.17.3). - U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); - else - U.setBaseAddress(TheCU.getRanges().front().getStart()); - U.attachRangesOrLowHighPC(U.getUnitDie(), TheCU.takeRanges()); - } - - if (getDwarfVersion() >= 5) { - if (U.hasRangeLists()) - U.addRnglistsBase(); - - if (!DebugLocs.getLists().empty() && !useSplitDwarf()) - U.addLoclistsBase(); - } - - auto *CUNode = cast<DICompileUnit>(P.first); - // If compile Unit has macros, emit "DW_AT_macro_info" attribute. - if (CUNode->getMacros()) - U.addSectionLabel(U.getUnitDie(), dwarf::DW_AT_macro_info, - U.getMacroLabelBegin(), - TLOF.getDwarfMacinfoSection()->getBeginSymbol()); - } - - // Emit all frontend-produced Skeleton CUs, i.e., Clang modules. - for (auto *CUNode : MMI->getModule()->debug_compile_units()) - if (CUNode->getDWOId()) - getOrCreateDwarfCompileUnit(CUNode); - - // Compute DIE offsets and sizes. - InfoHolder.computeSizeAndOffsets(); - if (useSplitDwarf()) - SkeletonHolder.computeSizeAndOffsets(); -} - -// Emit all Dwarf sections that should come after the content. -void DwarfDebug::endModule() { - assert(CurFn == nullptr); - assert(CurMI == nullptr); - - // If we aren't actually generating debug info (check beginModule - - // conditionalized on !DisableDebugInfoPrinting and the presence of the - // llvm.dbg.cu metadata node) - if (!MMI->hasDebugInfo()) - return; - - // Finalize the debug info for the module. - finalizeModuleInfo(); - - emitDebugStr(); - - if (useSplitDwarf()) - emitDebugLocDWO(); - else - // Emit info into a debug loc section. - emitDebugLoc(); - - // Corresponding abbreviations into a abbrev section. - emitAbbreviations(); - - // Emit all the DIEs into a debug info section. - emitDebugInfo(); - - // Emit info into a debug aranges section. - if (GenerateARangeSection) - emitDebugARanges(); - - // Emit info into a debug ranges section. - emitDebugRanges(); - - // Emit info into a debug macinfo section. - emitDebugMacinfo(); - - if (useSplitDwarf()) { - emitDebugStrDWO(); - emitDebugInfoDWO(); - emitDebugAbbrevDWO(); - emitDebugLineDWO(); - emitDebugRangesDWO(); - } - - emitDebugAddr(); - - // Emit info into the dwarf accelerator table sections. - switch (getAccelTableKind()) { - case AccelTableKind::Apple: - emitAccelNames(); - emitAccelObjC(); - emitAccelNamespaces(); - emitAccelTypes(); - break; - case AccelTableKind::Dwarf: - emitAccelDebugNames(); - break; - case AccelTableKind::None: - break; - case AccelTableKind::Default: - llvm_unreachable("Default should have already been resolved."); - } - - // Emit the pubnames and pubtypes sections if requested. - emitDebugPubSections(); - - // clean up. - // FIXME: AbstractVariables.clear(); -} - -void DwarfDebug::ensureAbstractEntityIsCreated(DwarfCompileUnit &CU, - const DINode *Node, - const MDNode *ScopeNode) { - if (CU.getExistingAbstractEntity(Node)) - return; - - CU.createAbstractEntity(Node, LScopes.getOrCreateAbstractScope( - cast<DILocalScope>(ScopeNode))); -} - -void DwarfDebug::ensureAbstractEntityIsCreatedIfScoped(DwarfCompileUnit &CU, - const DINode *Node, const MDNode *ScopeNode) { - if (CU.getExistingAbstractEntity(Node)) - return; - - if (LexicalScope *Scope = - LScopes.findAbstractScope(cast_or_null<DILocalScope>(ScopeNode))) - CU.createAbstractEntity(Node, Scope); -} - -// Collect variable information from side table maintained by MF. -void DwarfDebug::collectVariableInfoFromMFTable( - DwarfCompileUnit &TheCU, DenseSet<InlinedEntity> &Processed) { - SmallDenseMap<InlinedEntity, DbgVariable *> MFVars; - for (const auto &VI : Asm->MF->getVariableDbgInfo()) { - if (!VI.Var) - continue; - assert(VI.Var->isValidLocationForIntrinsic(VI.Loc) && - "Expected inlined-at fields to agree"); - - InlinedEntity Var(VI.Var, VI.Loc->getInlinedAt()); - Processed.insert(Var); - LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc); - - // If variable scope is not found then skip this variable. - if (!Scope) - continue; - - ensureAbstractEntityIsCreatedIfScoped(TheCU, Var.first, Scope->getScopeNode()); - auto RegVar = llvm::make_unique<DbgVariable>( - cast<DILocalVariable>(Var.first), Var.second); - RegVar->initializeMMI(VI.Expr, VI.Slot); - if (DbgVariable *DbgVar = MFVars.lookup(Var)) - DbgVar->addMMIEntry(*RegVar); - else if (InfoHolder.addScopeVariable(Scope, RegVar.get())) { - MFVars.insert({Var, RegVar.get()}); - ConcreteEntities.push_back(std::move(RegVar)); - } - } -} - -// Get .debug_loc entry for the instruction range starting at MI. -static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) { - const DIExpression *Expr = MI->getDebugExpression(); - assert(MI->getNumOperands() == 4); - if (MI->getOperand(0).isReg()) { - auto RegOp = MI->getOperand(0); - auto Op1 = MI->getOperand(1); - // If the second operand is an immediate, this is a - // register-indirect address. - assert((!Op1.isImm() || (Op1.getImm() == 0)) && "unexpected offset"); - MachineLocation MLoc(RegOp.getReg(), Op1.isImm()); - return DebugLocEntry::Value(Expr, MLoc); - } - if (MI->getOperand(0).isImm()) - return DebugLocEntry::Value(Expr, MI->getOperand(0).getImm()); - if (MI->getOperand(0).isFPImm()) - return DebugLocEntry::Value(Expr, MI->getOperand(0).getFPImm()); - if (MI->getOperand(0).isCImm()) - return DebugLocEntry::Value(Expr, MI->getOperand(0).getCImm()); - - llvm_unreachable("Unexpected 4-operand DBG_VALUE instruction!"); -} - -/// If this and Next are describing different fragments of the same -/// variable, merge them by appending Next's values to the current -/// list of values. -/// Return true if the merge was successful. -bool DebugLocEntry::MergeValues(const DebugLocEntry &Next) { - if (Begin == Next.Begin) { - auto *FirstExpr = cast<DIExpression>(Values[0].Expression); - auto *FirstNextExpr = cast<DIExpression>(Next.Values[0].Expression); - if (!FirstExpr->isFragment() || !FirstNextExpr->isFragment()) - return false; - - // We can only merge entries if none of the fragments overlap any others. - // In doing so, we can take advantage of the fact that both lists are - // sorted. - for (unsigned i = 0, j = 0; i < Values.size(); ++i) { - for (; j < Next.Values.size(); ++j) { - int res = cast<DIExpression>(Values[i].Expression)->fragmentCmp( - cast<DIExpression>(Next.Values[j].Expression)); - if (res == 0) // The two expressions overlap, we can't merge. - return false; - // Values[i] is entirely before Next.Values[j], - // so go back to the next entry of Values. - else if (res == -1) - break; - // Next.Values[j] is entirely before Values[i], so go on to the - // next entry of Next.Values. - } - } - - addValues(Next.Values); - End = Next.End; - return true; - } - return false; -} - -/// Build the location list for all DBG_VALUEs in the function that -/// describe the same variable. If the ranges of several independent -/// fragments of the same variable overlap partially, split them up and -/// combine the ranges. The resulting DebugLocEntries are will have -/// strict monotonically increasing begin addresses and will never -/// overlap. -// -// Input: -// -// Ranges History [var, loc, fragment ofs size] -// 0 | [x, (reg0, fragment 0, 32)] -// 1 | | [x, (reg1, fragment 32, 32)] <- IsFragmentOfPrevEntry -// 2 | | ... -// 3 | [clobber reg0] -// 4 [x, (mem, fragment 0, 64)] <- overlapping with both previous fragments of -// x. -// -// Output: -// -// [0-1] [x, (reg0, fragment 0, 32)] -// [1-3] [x, (reg0, fragment 0, 32), (reg1, fragment 32, 32)] -// [3-4] [x, (reg1, fragment 32, 32)] -// [4- ] [x, (mem, fragment 0, 64)] -void -DwarfDebug::buildLocationList(SmallVectorImpl<DebugLocEntry> &DebugLoc, - const DbgValueHistoryMap::InstrRanges &Ranges) { - SmallVector<DebugLocEntry::Value, 4> OpenRanges; - - 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 a variable is inaccessible in this range. - if (Begin->getNumOperands() > 1 && - Begin->getOperand(0).isReg() && !Begin->getOperand(0).getReg()) { - OpenRanges.clear(); - continue; - } - - // If this fragment overlaps with any open ranges, truncate them. - const DIExpression *DIExpr = Begin->getDebugExpression(); - auto Last = remove_if(OpenRanges, [&](DebugLocEntry::Value R) { - return DIExpr->fragmentsOverlap(R.getExpression()); - }); - OpenRanges.erase(Last, OpenRanges.end()); - - 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 = Asm->getFunctionEnd(); - else - EndLabel = getLabelBeforeInsn(std::next(I)->first); - assert(EndLabel && "Forgot label after instruction ending a range!"); - - LLVM_DEBUG(dbgs() << "DotDebugLoc: " << *Begin << "\n"); - - auto Value = getDebugLocValue(Begin); - - // Omit entries with empty ranges as they do not have any effect in DWARF. - if (StartLabel == EndLabel) { - // If this is a fragment, we must still add the value to the list of - // open ranges, since it may describe non-overlapping parts of the - // variable. - if (DIExpr->isFragment()) - OpenRanges.push_back(Value); - LLVM_DEBUG(dbgs() << "Omitting location list entry with empty range.\n"); - continue; - } - - DebugLocEntry Loc(StartLabel, EndLabel, Value); - bool couldMerge = false; - - // If this is a fragment, it may belong to the current DebugLocEntry. - if (DIExpr->isFragment()) { - // Add this value to the list of open ranges. - OpenRanges.push_back(Value); - - // Attempt to add the fragment to the last entry. - if (!DebugLoc.empty()) - if (DebugLoc.back().MergeValues(Loc)) - couldMerge = true; - } - - if (!couldMerge) { - // Need to add a new DebugLocEntry. Add all values from still - // valid non-overlapping fragments. - if (OpenRanges.size()) - Loc.addValues(OpenRanges); - - DebugLoc.push_back(std::move(Loc)); - } - - // Attempt to coalesce the ranges of two otherwise identical - // DebugLocEntries. - auto CurEntry = DebugLoc.rbegin(); - LLVM_DEBUG({ - dbgs() << CurEntry->getValues().size() << " Values:\n"; - for (auto &Value : CurEntry->getValues()) - Value.dump(); - dbgs() << "-----\n"; - }); - - auto PrevEntry = std::next(CurEntry); - if (PrevEntry != DebugLoc.rend() && PrevEntry->MergeRanges(*CurEntry)) - DebugLoc.pop_back(); - } -} - -DbgEntity *DwarfDebug::createConcreteEntity(DwarfCompileUnit &TheCU, - LexicalScope &Scope, - const DINode *Node, - const DILocation *Location, - const MCSymbol *Sym) { - ensureAbstractEntityIsCreatedIfScoped(TheCU, Node, Scope.getScopeNode()); - if (isa<const DILocalVariable>(Node)) { - ConcreteEntities.push_back( - llvm::make_unique<DbgVariable>(cast<const DILocalVariable>(Node), - Location)); - InfoHolder.addScopeVariable(&Scope, - cast<DbgVariable>(ConcreteEntities.back().get())); - } else if (isa<const DILabel>(Node)) { - ConcreteEntities.push_back( - llvm::make_unique<DbgLabel>(cast<const DILabel>(Node), - Location, Sym)); - InfoHolder.addScopeLabel(&Scope, - cast<DbgLabel>(ConcreteEntities.back().get())); - } - return ConcreteEntities.back().get(); -} - -/// Determine whether a *singular* DBG_VALUE is valid for the entirety of its -/// enclosing lexical scope. The check ensures there are no other instructions -/// in the same lexical scope preceding the DBG_VALUE and that its range is -/// either open or otherwise rolls off the end of the scope. -static bool validThroughout(LexicalScopes &LScopes, - const MachineInstr *DbgValue, - const MachineInstr *RangeEnd) { - assert(DbgValue->getDebugLoc() && "DBG_VALUE without a debug location"); - auto MBB = DbgValue->getParent(); - auto DL = DbgValue->getDebugLoc(); - auto *LScope = LScopes.findLexicalScope(DL); - // Scope doesn't exist; this is a dead DBG_VALUE. - if (!LScope) - return false; - auto &LSRange = LScope->getRanges(); - if (LSRange.size() == 0) - return false; - - // Determine if the DBG_VALUE is valid at the beginning of its lexical block. - const MachineInstr *LScopeBegin = LSRange.front().first; - // Early exit if the lexical scope begins outside of the current block. - if (LScopeBegin->getParent() != MBB) - return false; - MachineBasicBlock::const_reverse_iterator Pred(DbgValue); - for (++Pred; Pred != MBB->rend(); ++Pred) { - if (Pred->getFlag(MachineInstr::FrameSetup)) - break; - auto PredDL = Pred->getDebugLoc(); - if (!PredDL || Pred->isMetaInstruction()) - continue; - // Check whether the instruction preceding the DBG_VALUE is in the same - // (sub)scope as the DBG_VALUE. - if (DL->getScope() == PredDL->getScope()) - return false; - auto *PredScope = LScopes.findLexicalScope(PredDL); - if (!PredScope || LScope->dominates(PredScope)) - return false; - } - - // If the range of the DBG_VALUE is open-ended, report success. - if (!RangeEnd) - return true; - - // Fail if there are instructions belonging to our scope in another block. - const MachineInstr *LScopeEnd = LSRange.back().second; - if (LScopeEnd->getParent() != MBB) - return false; - - // Single, constant DBG_VALUEs in the prologue are promoted to be live - // throughout the function. This is a hack, presumably for DWARF v2 and not - // necessarily correct. It would be much better to use a dbg.declare instead - // if we know the constant is live throughout the scope. - if (DbgValue->getOperand(0).isImm() && MBB->pred_empty()) - return true; - - return false; -} - -// Find variables for each lexical scope. -void DwarfDebug::collectEntityInfo(DwarfCompileUnit &TheCU, - const DISubprogram *SP, - DenseSet<InlinedEntity> &Processed) { - // Grab the variable info that was squirreled away in the MMI side-table. - collectVariableInfoFromMFTable(TheCU, Processed); - - for (const auto &I : DbgValues) { - InlinedEntity IV = I.first; - if (Processed.count(IV)) - continue; - - // Instruction ranges, specifying where IV is accessible. - const auto &Ranges = I.second; - if (Ranges.empty()) - continue; - - LexicalScope *Scope = nullptr; - const DILocalVariable *LocalVar = cast<DILocalVariable>(IV.first); - if (const DILocation *IA = IV.second) - Scope = LScopes.findInlinedScope(LocalVar->getScope(), IA); - else - Scope = LScopes.findLexicalScope(LocalVar->getScope()); - // If variable scope is not found then skip this variable. - if (!Scope) - continue; - - Processed.insert(IV); - DbgVariable *RegVar = cast<DbgVariable>(createConcreteEntity(TheCU, - *Scope, LocalVar, IV.second)); - - const MachineInstr *MInsn = Ranges.front().first; - assert(MInsn->isDebugValue() && "History must begin with debug value"); - - // Check if there is a single DBG_VALUE, valid throughout the var's scope. - if (Ranges.size() == 1 && - validThroughout(LScopes, MInsn, Ranges.front().second)) { - RegVar->initializeDbgValue(MInsn); - continue; - } - // Do not emit location lists if .debug_loc secton is disabled. - if (!useLocSection()) - continue; - - // Handle multiple DBG_VALUE instructions describing one variable. - DebugLocStream::ListBuilder List(DebugLocs, TheCU, *Asm, *RegVar, *MInsn); - - // Build the location list for this variable. - SmallVector<DebugLocEntry, 8> Entries; - buildLocationList(Entries, Ranges); - - // If the variable has a DIBasicType, extract it. Basic types cannot have - // unique identifiers, so don't bother resolving the type with the - // identifier map. - const DIBasicType *BT = dyn_cast<DIBasicType>( - static_cast<const Metadata *>(LocalVar->getType())); - - // Finalize the entry by lowering it into a DWARF bytestream. - for (auto &Entry : Entries) - Entry.finalize(*Asm, List, BT); - } - - // For each InlinedEntity collected from DBG_LABEL instructions, convert to - // DWARF-related DbgLabel. - for (const auto &I : DbgLabels) { - InlinedEntity IL = I.first; - const MachineInstr *MI = I.second; - if (MI == nullptr) - continue; - - LexicalScope *Scope = nullptr; - const DILabel *Label = cast<DILabel>(IL.first); - // Get inlined DILocation if it is inlined label. - if (const DILocation *IA = IL.second) - Scope = LScopes.findInlinedScope(Label->getScope(), IA); - else - Scope = LScopes.findLexicalScope(Label->getScope()); - // If label scope is not found then skip this label. - if (!Scope) - continue; - - Processed.insert(IL); - /// At this point, the temporary label is created. - /// Save the temporary label to DbgLabel entity to get the - /// actually address when generating Dwarf DIE. - MCSymbol *Sym = getLabelBeforeInsn(MI); - createConcreteEntity(TheCU, *Scope, Label, IL.second, Sym); - } - - // Collect info for variables/labels that were optimized out. - for (const DINode *DN : SP->getRetainedNodes()) { - if (!Processed.insert(InlinedEntity(DN, nullptr)).second) - continue; - LexicalScope *Scope = nullptr; - if (auto *DV = dyn_cast<DILocalVariable>(DN)) { - Scope = LScopes.findLexicalScope(DV->getScope()); - } else if (auto *DL = dyn_cast<DILabel>(DN)) { - Scope = LScopes.findLexicalScope(DL->getScope()); - } - - if (Scope) - createConcreteEntity(TheCU, *Scope, DN, nullptr); - } -} - -// Process beginning of an instruction. -void DwarfDebug::beginInstruction(const MachineInstr *MI) { - DebugHandlerBase::beginInstruction(MI); - assert(CurMI); - - const auto *SP = MI->getMF()->getFunction().getSubprogram(); - if (!SP || SP->getUnit()->getEmissionKind() == DICompileUnit::NoDebug) - return; - - // Check if source location changes, but ignore DBG_VALUE and CFI locations. - // If the instruction is part of the function frame setup code, do not emit - // any line record, as there is no correspondence with any user code. - if (MI->isMetaInstruction() || MI->getFlag(MachineInstr::FrameSetup)) - return; - const DebugLoc &DL = MI->getDebugLoc(); - // When we emit a line-0 record, we don't update PrevInstLoc; so look at - // the last line number actually emitted, to see if it was line 0. - unsigned LastAsmLine = - Asm->OutStreamer->getContext().getCurrentDwarfLoc().getLine(); - - // Request a label after the call in order to emit AT_return_pc information - // in call site entries. TODO: Add support for targets with delay slots. - if (SP->areAllCallsDescribed() && MI->isCall() && !MI->hasDelaySlot()) - requestLabelAfterInsn(MI); - - if (DL == PrevInstLoc) { - // If we have an ongoing unspecified location, nothing to do here. - if (!DL) - return; - // We have an explicit location, same as the previous location. - // But we might be coming back to it after a line 0 record. - if (LastAsmLine == 0 && DL.getLine() != 0) { - // Reinstate the source location but not marked as a statement. - const MDNode *Scope = DL.getScope(); - recordSourceLine(DL.getLine(), DL.getCol(), Scope, /*Flags=*/0); - } - return; - } - - if (!DL) { - // We have an unspecified location, which might want to be line 0. - // If we have already emitted a line-0 record, don't repeat it. - if (LastAsmLine == 0) - return; - // If user said Don't Do That, don't do that. - if (UnknownLocations == Disable) - return; - // See if we have a reason to emit a line-0 record now. - // Reasons to emit a line-0 record include: - // - User asked for it (UnknownLocations). - // - Instruction has a label, so it's referenced from somewhere else, - // possibly debug information; we want it to have a source location. - // - Instruction is at the top of a block; we don't want to inherit the - // location from the physically previous (maybe unrelated) block. - if (UnknownLocations == Enable || PrevLabel || - (PrevInstBB && PrevInstBB != MI->getParent())) { - // Preserve the file and column numbers, if we can, to save space in - // the encoded line table. - // Do not update PrevInstLoc, it remembers the last non-0 line. - const MDNode *Scope = nullptr; - unsigned Column = 0; - if (PrevInstLoc) { - Scope = PrevInstLoc.getScope(); - Column = PrevInstLoc.getCol(); - } - recordSourceLine(/*Line=*/0, Column, Scope, /*Flags=*/0); - } - return; - } - - // We have an explicit location, different from the previous location. - // Don't repeat a line-0 record, but otherwise emit the new location. - // (The new location might be an explicit line 0, which we do emit.) - if (PrevInstLoc && DL.getLine() == 0 && LastAsmLine == 0) - return; - unsigned Flags = 0; - if (DL == PrologEndLoc) { - Flags |= DWARF2_FLAG_PROLOGUE_END | DWARF2_FLAG_IS_STMT; - PrologEndLoc = DebugLoc(); - } - // If the line changed, we call that a new statement; unless we went to - // line 0 and came back, in which case it is not a new statement. - unsigned OldLine = PrevInstLoc ? PrevInstLoc.getLine() : LastAsmLine; - if (DL.getLine() && DL.getLine() != OldLine) - Flags |= DWARF2_FLAG_IS_STMT; - - const MDNode *Scope = DL.getScope(); - recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); - - // If we're not at line 0, remember this location. - if (DL.getLine()) - PrevInstLoc = DL; -} - -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.isMetaInstruction() && !MI.getFlag(MachineInstr::FrameSetup) && - MI.getDebugLoc()) - return MI.getDebugLoc(); - return DebugLoc(); -} - -// Gather pre-function debug information. Assumes being called immediately -// after the function entry point has been emitted. -void DwarfDebug::beginFunctionImpl(const MachineFunction *MF) { - CurFn = MF; - - auto *SP = MF->getFunction().getSubprogram(); - assert(LScopes.empty() || SP == LScopes.getCurrentFunctionScope()->getScopeNode()); - if (SP->getUnit()->getEmissionKind() == DICompileUnit::NoDebug) - return; - - DwarfCompileUnit &CU = getOrCreateDwarfCompileUnit(SP->getUnit()); - - // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function - // belongs to so that we add to the correct per-cu line table in the - // non-asm case. - if (Asm->OutStreamer->hasRawTextSupport()) - // Use a single line table if we are generating assembly. - Asm->OutStreamer->getContext().setDwarfCompileUnitID(0); - else - Asm->OutStreamer->getContext().setDwarfCompileUnitID(CU.getUniqueID()); - - // Record beginning of function. - PrologEndLoc = findPrologueEndLoc(MF); - if (PrologEndLoc) { - // We'd like to list the prologue as "not statements" but GDB behaves - // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. - auto *SP = PrologEndLoc->getInlinedAtScope()->getSubprogram(); - recordSourceLine(SP->getScopeLine(), 0, SP, DWARF2_FLAG_IS_STMT); - } -} - -void DwarfDebug::skippedNonDebugFunction() { - // If we don't have a subprogram 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. - PrevCU = nullptr; - CurFn = nullptr; -} - -// Gather and emit post-function debug information. -void DwarfDebug::endFunctionImpl(const MachineFunction *MF) { - const DISubprogram *SP = MF->getFunction().getSubprogram(); - - assert(CurFn == MF && - "endFunction should be called with the same function as beginFunction"); - - // Set DwarfDwarfCompileUnitID in MCContext to default value. - Asm->OutStreamer->getContext().setDwarfCompileUnitID(0); - - LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); - assert(!FnScope || SP == FnScope->getScopeNode()); - DwarfCompileUnit &TheCU = *CUMap.lookup(SP->getUnit()); - if (TheCU.getCUNode()->isDebugDirectivesOnly()) { - PrevLabel = nullptr; - CurFn = nullptr; - return; - } - - DenseSet<InlinedEntity> Processed; - collectEntityInfo(TheCU, SP, Processed); - - // Add the range of this function to the list of ranges for the CU. - TheCU.addRange(RangeSpan(Asm->getFunctionBegin(), Asm->getFunctionEnd())); - - // Under -gmlt, skip building the subprogram if there are no inlined - // subroutines inside it. But with -fdebug-info-for-profiling, the subprogram - // is still needed as we need its source location. - if (!TheCU.getCUNode()->getDebugInfoForProfiling() && - TheCU.getCUNode()->getEmissionKind() == DICompileUnit::LineTablesOnly && - LScopes.getAbstractScopesList().empty() && !IsDarwin) { - assert(InfoHolder.getScopeVariables().empty()); - PrevLabel = nullptr; - CurFn = nullptr; - return; - } - -#ifndef NDEBUG - size_t NumAbstractScopes = LScopes.getAbstractScopesList().size(); -#endif - // Construct abstract scopes. - for (LexicalScope *AScope : LScopes.getAbstractScopesList()) { - auto *SP = cast<DISubprogram>(AScope->getScopeNode()); - for (const DINode *DN : SP->getRetainedNodes()) { - if (!Processed.insert(InlinedEntity(DN, nullptr)).second) - continue; - - const MDNode *Scope = nullptr; - if (auto *DV = dyn_cast<DILocalVariable>(DN)) - Scope = DV->getScope(); - else if (auto *DL = dyn_cast<DILabel>(DN)) - Scope = DL->getScope(); - else - llvm_unreachable("Unexpected DI type!"); - - // Collect info for variables/labels that were optimized out. - ensureAbstractEntityIsCreated(TheCU, DN, Scope); - assert(LScopes.getAbstractScopesList().size() == NumAbstractScopes - && "ensureAbstractEntityIsCreated inserted abstract scopes"); - } - constructAbstractSubprogramScopeDIE(TheCU, AScope); - } - - ProcessedSPNodes.insert(SP); - DIE &ScopeDIE = TheCU.constructSubprogramScopeDIE(SP, FnScope); - if (auto *SkelCU = TheCU.getSkeleton()) - if (!LScopes.getAbstractScopesList().empty() && - TheCU.getCUNode()->getSplitDebugInlining()) - SkelCU->constructSubprogramScopeDIE(SP, FnScope); - - // Construct call site entries. - constructCallSiteEntryDIEs(*SP, TheCU, ScopeDIE, *MF); - - // Clear debug info - // 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) - InfoHolder.getScopeVariables().clear(); - InfoHolder.getScopeLabels().clear(); - PrevLabel = nullptr; - CurFn = nullptr; -} - -// Register a source line with debug info. Returns the unique label that was -// emitted and which provides correspondence to the source line list. -void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, - unsigned Flags) { - StringRef Fn; - unsigned FileNo = 1; - unsigned Discriminator = 0; - if (auto *Scope = cast_or_null<DIScope>(S)) { - Fn = Scope->getFilename(); - if (Line != 0 && getDwarfVersion() >= 4) - if (auto *LBF = dyn_cast<DILexicalBlockFile>(Scope)) - Discriminator = LBF->getDiscriminator(); - - unsigned CUID = Asm->OutStreamer->getContext().getDwarfCompileUnitID(); - FileNo = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID]) - .getOrCreateSourceID(Scope->getFile()); - } - Asm->OutStreamer->EmitDwarfLocDirective(FileNo, Line, Col, Flags, 0, - Discriminator, Fn); -} - -//===----------------------------------------------------------------------===// -// Emit Methods -//===----------------------------------------------------------------------===// - -// Emit the debug info section. -void DwarfDebug::emitDebugInfo() { - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - Holder.emitUnits(/* UseOffsets */ false); -} - -// Emit the abbreviation section. -void DwarfDebug::emitAbbreviations() { - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - - Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); -} - -void DwarfDebug::emitStringOffsetsTableHeader() { - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - Holder.getStringPool().emitStringOffsetsTableHeader( - *Asm, Asm->getObjFileLowering().getDwarfStrOffSection(), - Holder.getStringOffsetsStartSym()); -} - -template <typename AccelTableT> -void DwarfDebug::emitAccel(AccelTableT &Accel, MCSection *Section, - StringRef TableName) { - Asm->OutStreamer->SwitchSection(Section); - - // Emit the full data. - emitAppleAccelTable(Asm, Accel, TableName, Section->getBeginSymbol()); -} - -void DwarfDebug::emitAccelDebugNames() { - // Don't emit anything if we have no compilation units to index. - if (getUnits().empty()) - return; - - emitDWARF5AccelTable(Asm, AccelDebugNames, *this, getUnits()); -} - -// Emit visible names into a hashed accelerator table section. -void DwarfDebug::emitAccelNames() { - emitAccel(AccelNames, Asm->getObjFileLowering().getDwarfAccelNamesSection(), - "Names"); -} - -// Emit objective C classes and categories into a hashed accelerator table -// section. -void DwarfDebug::emitAccelObjC() { - emitAccel(AccelObjC, Asm->getObjFileLowering().getDwarfAccelObjCSection(), - "ObjC"); -} - -// Emit namespace dies into a hashed accelerator table. -void DwarfDebug::emitAccelNamespaces() { - emitAccel(AccelNamespace, - Asm->getObjFileLowering().getDwarfAccelNamespaceSection(), - "namespac"); -} - -// Emit type dies into a hashed accelerator table. -void DwarfDebug::emitAccelTypes() { - emitAccel(AccelTypes, Asm->getObjFileLowering().getDwarfAccelTypesSection(), - "types"); -} - -// Public name handling. -// The format for the various pubnames: -// -// dwarf pubnames - offset/name pairs where the offset is the offset into the CU -// for the DIE that is named. -// -// gnu pubnames - offset/index value/name tuples where the offset is the offset -// into the CU and the index value is computed according to the type of value -// for the DIE that is named. -// -// For type units the offset is the offset of the skeleton DIE. For split dwarf -// it's the offset within the debug_info/debug_types dwo section, however, the -// reference in the pubname header doesn't change. - -/// computeIndexValue - Compute the gdb index value for the DIE and CU. -static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU, - const DIE *Die) { - // Entities that ended up only in a Type Unit reference the CU instead (since - // the pub entry has offsets within the CU there's no real offset that can be - // provided anyway). As it happens all such entities (namespaces and types, - // types only in C++ at that) are rendered as TYPE+EXTERNAL. If this turns out - // not to be true it would be necessary to persist this information from the - // point at which the entry is added to the index data structure - since by - // the time the index is built from that, the original type/namespace DIE in a - // type unit has already been destroyed so it can't be queried for properties - // like tag, etc. - if (Die->getTag() == dwarf::DW_TAG_compile_unit) - return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, - dwarf::GIEL_EXTERNAL); - dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; - - // We could have a specification DIE that has our most of our knowledge, - // look for that now. - if (DIEValue SpecVal = Die->findAttribute(dwarf::DW_AT_specification)) { - DIE &SpecDIE = SpecVal.getDIEEntry().getEntry(); - if (SpecDIE.findAttribute(dwarf::DW_AT_external)) - Linkage = dwarf::GIEL_EXTERNAL; - } else if (Die->findAttribute(dwarf::DW_AT_external)) - Linkage = dwarf::GIEL_EXTERNAL; - - switch (Die->getTag()) { - case dwarf::DW_TAG_class_type: - case dwarf::DW_TAG_structure_type: - case dwarf::DW_TAG_union_type: - case dwarf::DW_TAG_enumeration_type: - return dwarf::PubIndexEntryDescriptor( - dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus - ? dwarf::GIEL_STATIC - : dwarf::GIEL_EXTERNAL); - case dwarf::DW_TAG_typedef: - case dwarf::DW_TAG_base_type: - case dwarf::DW_TAG_subrange_type: - return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); - case dwarf::DW_TAG_namespace: - return dwarf::GIEK_TYPE; - case dwarf::DW_TAG_subprogram: - return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); - case dwarf::DW_TAG_variable: - return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); - case dwarf::DW_TAG_enumerator: - return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, - dwarf::GIEL_STATIC); - default: - return dwarf::GIEK_NONE; - } -} - -/// emitDebugPubSections - Emit visible names and types into debug pubnames and -/// pubtypes sections. -void DwarfDebug::emitDebugPubSections() { - for (const auto &NU : CUMap) { - DwarfCompileUnit *TheU = NU.second; - if (!TheU->hasDwarfPubSections()) - continue; - - bool GnuStyle = TheU->getCUNode()->getNameTableKind() == - DICompileUnit::DebugNameTableKind::GNU; - - Asm->OutStreamer->SwitchSection( - GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() - : Asm->getObjFileLowering().getDwarfPubNamesSection()); - emitDebugPubSection(GnuStyle, "Names", TheU, TheU->getGlobalNames()); - - Asm->OutStreamer->SwitchSection( - GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() - : Asm->getObjFileLowering().getDwarfPubTypesSection()); - emitDebugPubSection(GnuStyle, "Types", TheU, TheU->getGlobalTypes()); - } -} - -void DwarfDebug::emitSectionReference(const DwarfCompileUnit &CU) { - if (useSectionsAsReferences()) - Asm->EmitDwarfOffset(CU.getSection()->getBeginSymbol(), - CU.getDebugSectionOffset()); - else - Asm->emitDwarfSymbolReference(CU.getLabelBegin()); -} - -void DwarfDebug::emitDebugPubSection(bool GnuStyle, StringRef Name, - DwarfCompileUnit *TheU, - const StringMap<const DIE *> &Globals) { - if (auto *Skeleton = TheU->getSkeleton()) - TheU = Skeleton; - - // Emit the header. - Asm->OutStreamer->AddComment("Length of Public " + Name + " Info"); - MCSymbol *BeginLabel = Asm->createTempSymbol("pub" + Name + "_begin"); - MCSymbol *EndLabel = Asm->createTempSymbol("pub" + Name + "_end"); - Asm->EmitLabelDifference(EndLabel, BeginLabel, 4); - - Asm->OutStreamer->EmitLabel(BeginLabel); - - Asm->OutStreamer->AddComment("DWARF Version"); - Asm->emitInt16(dwarf::DW_PUBNAMES_VERSION); - - Asm->OutStreamer->AddComment("Offset of Compilation Unit Info"); - emitSectionReference(*TheU); - - Asm->OutStreamer->AddComment("Compilation Unit Length"); - Asm->emitInt32(TheU->getLength()); - - // Emit the pubnames for this compilation unit. - for (const auto &GI : Globals) { - const char *Name = GI.getKeyData(); - const DIE *Entity = GI.second; - - Asm->OutStreamer->AddComment("DIE offset"); - Asm->emitInt32(Entity->getOffset()); - - if (GnuStyle) { - dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity); - Asm->OutStreamer->AddComment( - Twine("Attributes: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + - ", " + dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); - Asm->emitInt8(Desc.toBits()); - } - - Asm->OutStreamer->AddComment("External Name"); - Asm->OutStreamer->EmitBytes(StringRef(Name, GI.getKeyLength() + 1)); - } - - Asm->OutStreamer->AddComment("End Mark"); - Asm->emitInt32(0); - Asm->OutStreamer->EmitLabel(EndLabel); -} - -/// Emit null-terminated strings into a debug str section. -void DwarfDebug::emitDebugStr() { - MCSection *StringOffsetsSection = nullptr; - if (useSegmentedStringOffsetsTable()) { - emitStringOffsetsTableHeader(); - StringOffsetsSection = Asm->getObjFileLowering().getDwarfStrOffSection(); - } - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection(), - StringOffsetsSection, /* UseRelativeOffsets = */ true); -} - -void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer, - const DebugLocStream::Entry &Entry) { - auto &&Comments = DebugLocs.getComments(Entry); - auto Comment = Comments.begin(); - auto End = Comments.end(); - for (uint8_t Byte : DebugLocs.getBytes(Entry)) - Streamer.EmitInt8(Byte, Comment != End ? *(Comment++) : ""); -} - -static void emitDebugLocValue(const AsmPrinter &AP, const DIBasicType *BT, - const DebugLocEntry::Value &Value, - DwarfExpression &DwarfExpr) { - auto *DIExpr = Value.getExpression(); - DIExpressionCursor ExprCursor(DIExpr); - DwarfExpr.addFragmentOffset(DIExpr); - // Regular entry. - if (Value.isInt()) { - if (BT && (BT->getEncoding() == dwarf::DW_ATE_signed || - BT->getEncoding() == dwarf::DW_ATE_signed_char)) - DwarfExpr.addSignedConstant(Value.getInt()); - else - DwarfExpr.addUnsignedConstant(Value.getInt()); - } else if (Value.isLocation()) { - MachineLocation Location = Value.getLoc(); - if (Location.isIndirect()) - DwarfExpr.setMemoryLocationKind(); - DIExpressionCursor Cursor(DIExpr); - const TargetRegisterInfo &TRI = *AP.MF->getSubtarget().getRegisterInfo(); - if (!DwarfExpr.addMachineRegExpression(TRI, Cursor, Location.getReg())) - return; - return DwarfExpr.addExpression(std::move(Cursor)); - } else if (Value.isConstantFP()) { - APInt RawBytes = Value.getConstantFP()->getValueAPF().bitcastToAPInt(); - DwarfExpr.addUnsignedConstant(RawBytes); - } - DwarfExpr.addExpression(std::move(ExprCursor)); -} - -void DebugLocEntry::finalize(const AsmPrinter &AP, - DebugLocStream::ListBuilder &List, - const DIBasicType *BT) { - assert(Begin != End && "unexpected location list entry with empty range"); - DebugLocStream::EntryBuilder Entry(List, Begin, End); - BufferByteStreamer Streamer = Entry.getStreamer(); - DebugLocDwarfExpression DwarfExpr(AP.getDwarfVersion(), Streamer); - const DebugLocEntry::Value &Value = Values[0]; - if (Value.isFragment()) { - // Emit all fragments that belong to the same variable and range. - assert(llvm::all_of(Values, [](DebugLocEntry::Value P) { - return P.isFragment(); - }) && "all values are expected to be fragments"); - assert(std::is_sorted(Values.begin(), Values.end()) && - "fragments are expected to be sorted"); - - for (auto Fragment : Values) - emitDebugLocValue(AP, BT, Fragment, DwarfExpr); - - } else { - assert(Values.size() == 1 && "only fragments may have >1 value"); - emitDebugLocValue(AP, BT, Value, DwarfExpr); - } - DwarfExpr.finalize(); -} - -void DwarfDebug::emitDebugLocEntryLocation(const DebugLocStream::Entry &Entry) { - // Emit the size. - Asm->OutStreamer->AddComment("Loc expr size"); - if (getDwarfVersion() >= 5) - Asm->EmitULEB128(DebugLocs.getBytes(Entry).size()); - else - Asm->emitInt16(DebugLocs.getBytes(Entry).size()); - // Emit the entry. - APByteStreamer Streamer(*Asm); - emitDebugLocEntry(Streamer, Entry); -} - -// Emit the common part of the DWARF 5 range/locations list tables header. -static void emitListsTableHeaderStart(AsmPrinter *Asm, const DwarfFile &Holder, - MCSymbol *TableStart, - MCSymbol *TableEnd) { - // Build the table header, which starts with the length field. - Asm->OutStreamer->AddComment("Length"); - Asm->EmitLabelDifference(TableEnd, TableStart, 4); - Asm->OutStreamer->EmitLabel(TableStart); - // Version number (DWARF v5 and later). - Asm->OutStreamer->AddComment("Version"); - Asm->emitInt16(Asm->OutStreamer->getContext().getDwarfVersion()); - // Address size. - Asm->OutStreamer->AddComment("Address size"); - Asm->emitInt8(Asm->MAI->getCodePointerSize()); - // Segment selector size. - Asm->OutStreamer->AddComment("Segment selector size"); - Asm->emitInt8(0); -} - -// Emit the header of a DWARF 5 range list table list table. Returns the symbol -// that designates the end of the table for the caller to emit when the table is -// complete. -static MCSymbol *emitRnglistsTableHeader(AsmPrinter *Asm, - const DwarfFile &Holder) { - MCSymbol *TableStart = Asm->createTempSymbol("debug_rnglist_table_start"); - MCSymbol *TableEnd = Asm->createTempSymbol("debug_rnglist_table_end"); - emitListsTableHeaderStart(Asm, Holder, TableStart, TableEnd); - - Asm->OutStreamer->AddComment("Offset entry count"); - Asm->emitInt32(Holder.getRangeLists().size()); - Asm->OutStreamer->EmitLabel(Holder.getRnglistsTableBaseSym()); - - for (const RangeSpanList &List : Holder.getRangeLists()) - Asm->EmitLabelDifference(List.getSym(), Holder.getRnglistsTableBaseSym(), - 4); - - return TableEnd; -} - -// Emit the header of a DWARF 5 locations list table. Returns the symbol that -// designates the end of the table for the caller to emit when the table is -// complete. -static MCSymbol *emitLoclistsTableHeader(AsmPrinter *Asm, - const DwarfFile &Holder) { - MCSymbol *TableStart = Asm->createTempSymbol("debug_loclist_table_start"); - MCSymbol *TableEnd = Asm->createTempSymbol("debug_loclist_table_end"); - emitListsTableHeaderStart(Asm, Holder, TableStart, TableEnd); - - // FIXME: Generate the offsets table and use DW_FORM_loclistx with the - // DW_AT_loclists_base attribute. Until then set the number of offsets to 0. - Asm->OutStreamer->AddComment("Offset entry count"); - Asm->emitInt32(0); - Asm->OutStreamer->EmitLabel(Holder.getLoclistsTableBaseSym()); - - return TableEnd; -} - -// Emit locations into the .debug_loc/.debug_rnglists section. -void DwarfDebug::emitDebugLoc() { - if (DebugLocs.getLists().empty()) - return; - - bool IsLocLists = getDwarfVersion() >= 5; - MCSymbol *TableEnd = nullptr; - if (IsLocLists) { - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfLoclistsSection()); - TableEnd = emitLoclistsTableHeader(Asm, useSplitDwarf() ? SkeletonHolder - : InfoHolder); - } else { - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfLocSection()); - } - - unsigned char Size = Asm->MAI->getCodePointerSize(); - for (const auto &List : DebugLocs.getLists()) { - Asm->OutStreamer->EmitLabel(List.Label); - - const DwarfCompileUnit *CU = List.CU; - const MCSymbol *Base = CU->getBaseAddress(); - for (const auto &Entry : DebugLocs.getEntries(List)) { - if (Base) { - // Set up the range. This range is relative to the entry point of the - // compile unit. This is a hard coded 0 for low_pc when we're emitting - // ranges, or the DW_AT_low_pc on the compile unit otherwise. - if (IsLocLists) { - Asm->OutStreamer->AddComment("DW_LLE_offset_pair"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_LLE_offset_pair, 1); - Asm->OutStreamer->AddComment(" starting offset"); - Asm->EmitLabelDifferenceAsULEB128(Entry.BeginSym, Base); - Asm->OutStreamer->AddComment(" ending offset"); - Asm->EmitLabelDifferenceAsULEB128(Entry.EndSym, Base); - } else { - Asm->EmitLabelDifference(Entry.BeginSym, Base, Size); - Asm->EmitLabelDifference(Entry.EndSym, Base, Size); - } - - emitDebugLocEntryLocation(Entry); - continue; - } - - // We have no base address. - if (IsLocLists) { - // TODO: Use DW_LLE_base_addressx + DW_LLE_offset_pair, or - // DW_LLE_startx_length in case if there is only a single range. - // That should reduce the size of the debug data emited. - // For now just use the DW_LLE_startx_length for all cases. - Asm->OutStreamer->AddComment("DW_LLE_startx_length"); - Asm->emitInt8(dwarf::DW_LLE_startx_length); - Asm->OutStreamer->AddComment(" start idx"); - Asm->EmitULEB128(AddrPool.getIndex(Entry.BeginSym)); - Asm->OutStreamer->AddComment(" length"); - Asm->EmitLabelDifferenceAsULEB128(Entry.EndSym, Entry.BeginSym); - } else { - Asm->OutStreamer->EmitSymbolValue(Entry.BeginSym, Size); - Asm->OutStreamer->EmitSymbolValue(Entry.EndSym, Size); - } - - emitDebugLocEntryLocation(Entry); - } - - if (IsLocLists) { - // .debug_loclists section ends with DW_LLE_end_of_list. - Asm->OutStreamer->AddComment("DW_LLE_end_of_list"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_LLE_end_of_list, 1); - } else { - // Terminate the .debug_loc list with two 0 values. - Asm->OutStreamer->EmitIntValue(0, Size); - Asm->OutStreamer->EmitIntValue(0, Size); - } - } - - if (TableEnd) - Asm->OutStreamer->EmitLabel(TableEnd); -} - -void DwarfDebug::emitDebugLocDWO() { - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfLocDWOSection()); - for (const auto &List : DebugLocs.getLists()) { - Asm->OutStreamer->EmitLabel(List.Label); - for (const auto &Entry : DebugLocs.getEntries(List)) { - // GDB only supports startx_length in pre-standard split-DWARF. - // (in v5 standard loclists, it currently* /only/ supports base_address + - // offset_pair, so the implementations can't really share much since they - // need to use different representations) - // * as of October 2018, at least - // Ideally/in v5, this could use SectionLabels to reuse existing addresses - // in the address pool to minimize object size/relocations. - Asm->emitInt8(dwarf::DW_LLE_startx_length); - unsigned idx = AddrPool.getIndex(Entry.BeginSym); - Asm->EmitULEB128(idx); - Asm->EmitLabelDifference(Entry.EndSym, Entry.BeginSym, 4); - - emitDebugLocEntryLocation(Entry); - } - Asm->emitInt8(dwarf::DW_LLE_end_of_list); - } -} - -struct ArangeSpan { - const MCSymbol *Start, *End; -}; - -// Emit a debug aranges section, containing a CU lookup for any -// address we can tie back to a CU. -void DwarfDebug::emitDebugARanges() { - // Provides a unique id per text section. - MapVector<MCSection *, SmallVector<SymbolCU, 8>> SectionMap; - - // Filter labels by section. - for (const SymbolCU &SCU : ArangeLabels) { - if (SCU.Sym->isInSection()) { - // Make a note of this symbol and it's section. - MCSection *Section = &SCU.Sym->getSection(); - if (!Section->getKind().isMetadata()) - SectionMap[Section].push_back(SCU); - } else { - // Some symbols (e.g. common/bss on mach-o) can have no section but still - // appear in the output. This sucks as we rely on sections to build - // arange spans. We can do it without, but it's icky. - SectionMap[nullptr].push_back(SCU); - } - } - - DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> Spans; - - for (auto &I : SectionMap) { - MCSection *Section = I.first; - SmallVector<SymbolCU, 8> &List = I.second; - if (List.size() < 1) - continue; - - // If we have no section (e.g. common), just write out - // individual spans for each symbol. - if (!Section) { - for (const SymbolCU &Cur : List) { - ArangeSpan Span; - Span.Start = Cur.Sym; - Span.End = nullptr; - assert(Cur.CU); - Spans[Cur.CU].push_back(Span); - } - continue; - } - - // Sort the symbols by offset within the section. - std::stable_sort( - List.begin(), List.end(), [&](const SymbolCU &A, const SymbolCU &B) { - unsigned IA = A.Sym ? Asm->OutStreamer->GetSymbolOrder(A.Sym) : 0; - unsigned IB = B.Sym ? Asm->OutStreamer->GetSymbolOrder(B.Sym) : 0; - - // Symbols with no order assigned should be placed at the end. - // (e.g. section end labels) - if (IA == 0) - return false; - if (IB == 0) - return true; - return IA < IB; - }); - - // Insert a final terminator. - List.push_back(SymbolCU(nullptr, Asm->OutStreamer->endSection(Section))); - - // Build spans between each label. - const MCSymbol *StartSym = List[0].Sym; - for (size_t n = 1, e = List.size(); n < e; n++) { - const SymbolCU &Prev = List[n - 1]; - const SymbolCU &Cur = List[n]; - - // Try and build the longest span we can within the same CU. - if (Cur.CU != Prev.CU) { - ArangeSpan Span; - Span.Start = StartSym; - Span.End = Cur.Sym; - assert(Prev.CU); - Spans[Prev.CU].push_back(Span); - StartSym = Cur.Sym; - } - } - } - - // Start the dwarf aranges section. - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfARangesSection()); - - unsigned PtrSize = Asm->MAI->getCodePointerSize(); - - // Build a list of CUs used. - std::vector<DwarfCompileUnit *> CUs; - for (const auto &it : Spans) { - DwarfCompileUnit *CU = it.first; - CUs.push_back(CU); - } - - // Sort the CU list (again, to ensure consistent output order). - llvm::sort(CUs, [](const DwarfCompileUnit *A, const DwarfCompileUnit *B) { - return A->getUniqueID() < B->getUniqueID(); - }); - - // Emit an arange table for each CU we used. - for (DwarfCompileUnit *CU : CUs) { - std::vector<ArangeSpan> &List = Spans[CU]; - - // Describe the skeleton CU's offset and length, not the dwo file's. - if (auto *Skel = CU->getSkeleton()) - CU = Skel; - - // Emit size of content not including length itself. - unsigned ContentSize = - sizeof(int16_t) + // DWARF ARange version number - sizeof(int32_t) + // Offset of CU in the .debug_info section - sizeof(int8_t) + // Pointer Size (in bytes) - sizeof(int8_t); // Segment Size (in bytes) - - unsigned TupleSize = PtrSize * 2; - - // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. - unsigned Padding = - OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize); - - ContentSize += Padding; - ContentSize += (List.size() + 1) * TupleSize; - - // For each compile unit, write the list of spans it covers. - Asm->OutStreamer->AddComment("Length of ARange Set"); - Asm->emitInt32(ContentSize); - Asm->OutStreamer->AddComment("DWARF Arange version number"); - Asm->emitInt16(dwarf::DW_ARANGES_VERSION); - Asm->OutStreamer->AddComment("Offset Into Debug Info Section"); - emitSectionReference(*CU); - Asm->OutStreamer->AddComment("Address Size (in bytes)"); - Asm->emitInt8(PtrSize); - Asm->OutStreamer->AddComment("Segment Size (in bytes)"); - Asm->emitInt8(0); - - Asm->OutStreamer->emitFill(Padding, 0xff); - - for (const ArangeSpan &Span : List) { - Asm->EmitLabelReference(Span.Start, PtrSize); - - // Calculate the size as being from the span start to it's end. - if (Span.End) { - Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); - } else { - // For symbols without an end marker (e.g. common), we - // write a single arange entry containing just that one symbol. - uint64_t Size = SymSize[Span.Start]; - if (Size == 0) - Size = 1; - - Asm->OutStreamer->EmitIntValue(Size, PtrSize); - } - } - - Asm->OutStreamer->AddComment("ARange terminator"); - Asm->OutStreamer->EmitIntValue(0, PtrSize); - Asm->OutStreamer->EmitIntValue(0, PtrSize); - } -} - -/// Emit a single range list. We handle both DWARF v5 and earlier. -static void emitRangeList(DwarfDebug &DD, AsmPrinter *Asm, - const RangeSpanList &List) { - - auto DwarfVersion = DD.getDwarfVersion(); - // Emit our symbol so we can find the beginning of the range. - Asm->OutStreamer->EmitLabel(List.getSym()); - // Gather all the ranges that apply to the same section so they can share - // a base address entry. - MapVector<const MCSection *, std::vector<const RangeSpan *>> SectionRanges; - // Size for our labels. - auto Size = Asm->MAI->getCodePointerSize(); - - for (const RangeSpan &Range : List.getRanges()) - SectionRanges[&Range.getStart()->getSection()].push_back(&Range); - - const DwarfCompileUnit &CU = List.getCU(); - const MCSymbol *CUBase = CU.getBaseAddress(); - bool BaseIsSet = false; - for (const auto &P : SectionRanges) { - // Don't bother with a base address entry if there's only one range in - // this section in this range list - for example ranges for a CU will - // usually consist of single regions from each of many sections - // (-ffunction-sections, or just C++ inline functions) except under LTO - // or optnone where there may be holes in a single CU's section - // contributions. - auto *Base = CUBase; - if (!Base && (P.second.size() > 1 || DwarfVersion < 5) && - (CU.getCUNode()->getRangesBaseAddress() || DwarfVersion >= 5)) { - BaseIsSet = true; - // FIXME/use care: This may not be a useful base address if it's not - // the lowest address/range in this object. - Base = P.second.front()->getStart(); - if (DwarfVersion >= 5) { - Base = DD.getSectionLabel(&Base->getSection()); - Asm->OutStreamer->AddComment("DW_RLE_base_addressx"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_RLE_base_addressx, 1); - Asm->OutStreamer->AddComment(" base address index"); - Asm->EmitULEB128(DD.getAddressPool().getIndex(Base)); - } else { - Asm->OutStreamer->EmitIntValue(-1, Size); - Asm->OutStreamer->AddComment(" base address"); - Asm->OutStreamer->EmitSymbolValue(Base, Size); - } - } else if (BaseIsSet && DwarfVersion < 5) { - BaseIsSet = false; - assert(!Base); - Asm->OutStreamer->EmitIntValue(-1, Size); - Asm->OutStreamer->EmitIntValue(0, Size); - } - - for (const auto *RS : P.second) { - const MCSymbol *Begin = RS->getStart(); - const MCSymbol *End = RS->getEnd(); - assert(Begin && "Range without a begin symbol?"); - assert(End && "Range without an end symbol?"); - if (Base) { - if (DwarfVersion >= 5) { - // Emit DW_RLE_offset_pair when we have a base. - Asm->OutStreamer->AddComment("DW_RLE_offset_pair"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_RLE_offset_pair, 1); - Asm->OutStreamer->AddComment(" starting offset"); - Asm->EmitLabelDifferenceAsULEB128(Begin, Base); - Asm->OutStreamer->AddComment(" ending offset"); - Asm->EmitLabelDifferenceAsULEB128(End, Base); - } else { - Asm->EmitLabelDifference(Begin, Base, Size); - Asm->EmitLabelDifference(End, Base, Size); - } - } else if (DwarfVersion >= 5) { - Asm->OutStreamer->AddComment("DW_RLE_startx_length"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_RLE_startx_length, 1); - Asm->OutStreamer->AddComment(" start index"); - Asm->EmitULEB128(DD.getAddressPool().getIndex(Begin)); - Asm->OutStreamer->AddComment(" length"); - Asm->EmitLabelDifferenceAsULEB128(End, Begin); - } else { - Asm->OutStreamer->EmitSymbolValue(Begin, Size); - Asm->OutStreamer->EmitSymbolValue(End, Size); - } - } - } - if (DwarfVersion >= 5) { - Asm->OutStreamer->AddComment("DW_RLE_end_of_list"); - Asm->OutStreamer->EmitIntValue(dwarf::DW_RLE_end_of_list, 1); - } else { - // Terminate the list with two 0 values. - Asm->OutStreamer->EmitIntValue(0, Size); - Asm->OutStreamer->EmitIntValue(0, Size); - } -} - -static void emitDebugRangesImpl(DwarfDebug &DD, AsmPrinter *Asm, - const DwarfFile &Holder, MCSymbol *TableEnd) { - for (const RangeSpanList &List : Holder.getRangeLists()) - emitRangeList(DD, Asm, List); - - if (TableEnd) - Asm->OutStreamer->EmitLabel(TableEnd); -} - -/// Emit address ranges into the .debug_ranges section or into the DWARF v5 -/// .debug_rnglists section. -void DwarfDebug::emitDebugRanges() { - if (CUMap.empty()) - return; - - const auto &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - - if (Holder.getRangeLists().empty()) - return; - - assert(useRangesSection()); - assert(llvm::none_of(CUMap, [](const decltype(CUMap)::value_type &Pair) { - return Pair.second->getCUNode()->isDebugDirectivesOnly(); - })); - - // Start the dwarf ranges section. - MCSymbol *TableEnd = nullptr; - if (getDwarfVersion() >= 5) { - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfRnglistsSection()); - TableEnd = emitRnglistsTableHeader(Asm, Holder); - } else - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfRangesSection()); - - emitDebugRangesImpl(*this, Asm, Holder, TableEnd); -} - -void DwarfDebug::emitDebugRangesDWO() { - assert(useSplitDwarf()); - - if (CUMap.empty()) - return; - - const auto &Holder = InfoHolder; - - if (Holder.getRangeLists().empty()) - return; - - assert(getDwarfVersion() >= 5); - assert(useRangesSection()); - assert(llvm::none_of(CUMap, [](const decltype(CUMap)::value_type &Pair) { - return Pair.second->getCUNode()->isDebugDirectivesOnly(); - })); - - // Start the dwarf ranges section. - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfRnglistsDWOSection()); - MCSymbol *TableEnd = emitRnglistsTableHeader(Asm, Holder); - - emitDebugRangesImpl(*this, Asm, Holder, TableEnd); -} - -void DwarfDebug::handleMacroNodes(DIMacroNodeArray Nodes, DwarfCompileUnit &U) { - for (auto *MN : Nodes) { - if (auto *M = dyn_cast<DIMacro>(MN)) - emitMacro(*M); - else if (auto *F = dyn_cast<DIMacroFile>(MN)) - emitMacroFile(*F, U); - else - llvm_unreachable("Unexpected DI type!"); - } -} - -void DwarfDebug::emitMacro(DIMacro &M) { - Asm->EmitULEB128(M.getMacinfoType()); - Asm->EmitULEB128(M.getLine()); - StringRef Name = M.getName(); - StringRef Value = M.getValue(); - Asm->OutStreamer->EmitBytes(Name); - if (!Value.empty()) { - // There should be one space between macro name and macro value. - Asm->emitInt8(' '); - Asm->OutStreamer->EmitBytes(Value); - } - Asm->emitInt8('\0'); -} - -void DwarfDebug::emitMacroFile(DIMacroFile &F, DwarfCompileUnit &U) { - assert(F.getMacinfoType() == dwarf::DW_MACINFO_start_file); - Asm->EmitULEB128(dwarf::DW_MACINFO_start_file); - Asm->EmitULEB128(F.getLine()); - Asm->EmitULEB128(U.getOrCreateSourceID(F.getFile())); - handleMacroNodes(F.getElements(), U); - Asm->EmitULEB128(dwarf::DW_MACINFO_end_file); -} - -/// Emit macros into a debug macinfo section. -void DwarfDebug::emitDebugMacinfo() { - if (CUMap.empty()) - return; - - if (llvm::all_of(CUMap, [](const decltype(CUMap)::value_type &Pair) { - return Pair.second->getCUNode()->isDebugDirectivesOnly(); - })) - return; - - // Start the dwarf macinfo section. - Asm->OutStreamer->SwitchSection( - Asm->getObjFileLowering().getDwarfMacinfoSection()); - - for (const auto &P : CUMap) { - auto &TheCU = *P.second; - if (TheCU.getCUNode()->isDebugDirectivesOnly()) - continue; - auto *SkCU = TheCU.getSkeleton(); - DwarfCompileUnit &U = SkCU ? *SkCU : TheCU; - auto *CUNode = cast<DICompileUnit>(P.first); - DIMacroNodeArray Macros = CUNode->getMacros(); - if (!Macros.empty()) { - Asm->OutStreamer->EmitLabel(U.getMacroLabelBegin()); - handleMacroNodes(Macros, U); - } - } - Asm->OutStreamer->AddComment("End Of Macro List Mark"); - Asm->emitInt8(0); -} - -// DWARF5 Experimental Separate Dwarf emitters. - -void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die, - std::unique_ptr<DwarfCompileUnit> NewU) { - - if (!CompilationDir.empty()) - NewU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); - - addGnuPubAttributes(*NewU, Die); - - SkeletonHolder.addUnit(std::move(NewU)); -} - -DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) { - - auto OwnedUnit = llvm::make_unique<DwarfCompileUnit>( - CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder); - DwarfCompileUnit &NewCU = *OwnedUnit; - NewCU.setSection(Asm->getObjFileLowering().getDwarfInfoSection()); - - NewCU.initStmtList(); - - if (useSegmentedStringOffsetsTable()) - NewCU.addStringOffsetsStart(); - - initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit)); - - return NewCU; -} - -// Emit the .debug_info.dwo section for separated dwarf. This contains the -// compile units that would normally be in debug_info. -void DwarfDebug::emitDebugInfoDWO() { - assert(useSplitDwarf() && "No split dwarf debug info?"); - // Don't emit relocations into the dwo file. - InfoHolder.emitUnits(/* UseOffsets */ true); -} - -// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the -// abbreviations for the .debug_info.dwo section. -void DwarfDebug::emitDebugAbbrevDWO() { - assert(useSplitDwarf() && "No split dwarf?"); - InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection()); -} - -void DwarfDebug::emitDebugLineDWO() { - assert(useSplitDwarf() && "No split dwarf?"); - SplitTypeUnitFileTable.Emit( - *Asm->OutStreamer, MCDwarfLineTableParams(), - Asm->getObjFileLowering().getDwarfLineDWOSection()); -} - -void DwarfDebug::emitStringOffsetsTableHeaderDWO() { - assert(useSplitDwarf() && "No split dwarf?"); - InfoHolder.getStringPool().emitStringOffsetsTableHeader( - *Asm, Asm->getObjFileLowering().getDwarfStrOffDWOSection(), - InfoHolder.getStringOffsetsStartSym()); -} - -// Emit the .debug_str.dwo section for separated dwarf. This contains the -// string section and is identical in format to traditional .debug_str -// sections. -void DwarfDebug::emitDebugStrDWO() { - if (useSegmentedStringOffsetsTable()) - emitStringOffsetsTableHeaderDWO(); - assert(useSplitDwarf() && "No split dwarf?"); - MCSection *OffSec = Asm->getObjFileLowering().getDwarfStrOffDWOSection(); - InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), - OffSec, /* UseRelativeOffsets = */ false); -} - -// Emit address pool. -void DwarfDebug::emitDebugAddr() { - AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection()); -} - -MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) { - if (!useSplitDwarf()) - return nullptr; - const DICompileUnit *DIUnit = CU.getCUNode(); - SplitTypeUnitFileTable.maybeSetRootFile( - DIUnit->getDirectory(), DIUnit->getFilename(), - CU.getMD5AsBytes(DIUnit->getFile()), DIUnit->getSource()); - return &SplitTypeUnitFileTable; -} - -uint64_t DwarfDebug::makeTypeSignature(StringRef Identifier) { - MD5 Hash; - Hash.update(Identifier); - // ... take the least significant 8 bytes and return those. Our MD5 - // implementation always returns its results in little endian, so we actually - // need the "high" word. - MD5::MD5Result Result; - Hash.final(Result); - return Result.high(); -} - -void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU, - StringRef Identifier, DIE &RefDie, - const DICompositeType *CTy) { - // Fast path if we're building some type units and one has already used the - // address pool we know we're going to throw away all this work anyway, so - // don't bother building dependent types. - if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed()) - return; - - auto Ins = TypeSignatures.insert(std::make_pair(CTy, 0)); - if (!Ins.second) { - CU.addDIETypeSignature(RefDie, Ins.first->second); - return; - } - - bool TopLevelType = TypeUnitsUnderConstruction.empty(); - AddrPool.resetUsedFlag(); - - auto OwnedUnit = llvm::make_unique<DwarfTypeUnit>(CU, Asm, this, &InfoHolder, - getDwoLineTable(CU)); - DwarfTypeUnit &NewTU = *OwnedUnit; - DIE &UnitDie = NewTU.getUnitDie(); - TypeUnitsUnderConstruction.emplace_back(std::move(OwnedUnit), CTy); - - NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2, - CU.getLanguage()); - - uint64_t Signature = makeTypeSignature(Identifier); - NewTU.setTypeSignature(Signature); - Ins.first->second = Signature; - - if (useSplitDwarf()) { - MCSection *Section = - getDwarfVersion() <= 4 - ? Asm->getObjFileLowering().getDwarfTypesDWOSection() - : Asm->getObjFileLowering().getDwarfInfoDWOSection(); - NewTU.setSection(Section); - } else { - MCSection *Section = - getDwarfVersion() <= 4 - ? Asm->getObjFileLowering().getDwarfTypesSection(Signature) - : Asm->getObjFileLowering().getDwarfInfoSection(Signature); - NewTU.setSection(Section); - // Non-split type units reuse the compile unit's line table. - CU.applyStmtList(UnitDie); - } - - // Add DW_AT_str_offsets_base to the type unit DIE, but not for split type - // units. - if (useSegmentedStringOffsetsTable() && !useSplitDwarf()) - NewTU.addStringOffsetsStart(); - - NewTU.setType(NewTU.createTypeDIE(CTy)); - - if (TopLevelType) { - auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction); - TypeUnitsUnderConstruction.clear(); - - // Types referencing entries in the address table cannot be placed in type - // units. - if (AddrPool.hasBeenUsed()) { - - // Remove all the types built while building this type. - // This is pessimistic as some of these types might not be dependent on - // the type that used an address. - for (const auto &TU : TypeUnitsToAdd) - TypeSignatures.erase(TU.second); - - // Construct this type in the CU directly. - // This is inefficient because all the dependent types will be rebuilt - // from scratch, including building them in type units, discovering that - // they depend on addresses, throwing them out and rebuilding them. - CU.constructTypeDIE(RefDie, cast<DICompositeType>(CTy)); - return; - } - - // If the type wasn't dependent on fission addresses, finish adding the type - // and all its dependent types. - for (auto &TU : TypeUnitsToAdd) { - InfoHolder.computeSizeAndOffsetsForUnit(TU.first.get()); - InfoHolder.emitUnit(TU.first.get(), useSplitDwarf()); - } - } - CU.addDIETypeSignature(RefDie, Signature); -} - -// Add the Name along with its companion DIE to the appropriate accelerator -// table (for AccelTableKind::Dwarf it's always AccelDebugNames, for -// AccelTableKind::Apple, we use the table we got as an argument). If -// accelerator tables are disabled, this function does nothing. -template <typename DataT> -void DwarfDebug::addAccelNameImpl(const DICompileUnit &CU, - AccelTable<DataT> &AppleAccel, StringRef Name, - const DIE &Die) { - if (getAccelTableKind() == AccelTableKind::None) - return; - - if (getAccelTableKind() != AccelTableKind::Apple && - CU.getNameTableKind() == DICompileUnit::DebugNameTableKind::None) - return; - - DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - DwarfStringPoolEntryRef Ref = Holder.getStringPool().getEntry(*Asm, Name); - - switch (getAccelTableKind()) { - case AccelTableKind::Apple: - AppleAccel.addName(Ref, Die); - break; - case AccelTableKind::Dwarf: - AccelDebugNames.addName(Ref, Die); - break; - case AccelTableKind::Default: - llvm_unreachable("Default should have already been resolved."); - case AccelTableKind::None: - llvm_unreachable("None handled above"); - } -} - -void DwarfDebug::addAccelName(const DICompileUnit &CU, StringRef Name, - const DIE &Die) { - addAccelNameImpl(CU, AccelNames, Name, Die); -} - -void DwarfDebug::addAccelObjC(const DICompileUnit &CU, StringRef Name, - const DIE &Die) { - // ObjC names go only into the Apple accelerator tables. - if (getAccelTableKind() == AccelTableKind::Apple) - addAccelNameImpl(CU, AccelObjC, Name, Die); -} - -void DwarfDebug::addAccelNamespace(const DICompileUnit &CU, StringRef Name, - const DIE &Die) { - addAccelNameImpl(CU, AccelNamespace, Name, Die); -} - -void DwarfDebug::addAccelType(const DICompileUnit &CU, StringRef Name, - const DIE &Die, char Flags) { - addAccelNameImpl(CU, AccelTypes, Name, Die); -} - -uint16_t DwarfDebug::getDwarfVersion() const { - return Asm->OutStreamer->getContext().getDwarfVersion(); -} - -void DwarfDebug::addSectionLabel(const MCSymbol *Sym) { - SectionLabels.insert(std::make_pair(&Sym->getSection(), Sym)); -} - -const MCSymbol *DwarfDebug::getSectionLabel(const MCSection *S) { - return SectionLabels.find(S)->second; -} |