From: Rafael Espindola Date: Tue, 10 Mar 2015 16:58:10 +0000 (+0000) Subject: Store an optional section start label in MCSection. X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0f4df6dc6f0811556687bc59f8f34b6343078293;p=oota-llvm.git Store an optional section start label in MCSection. This makes code that uses section relative expressions (debug info) simpler and less brittle. This is still a bit awkward as the symbol is created late and has to be stored in a mutable field. I will move the symbol creation earlier in the next patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231802 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/CodeGen/AsmPrinter.h b/include/llvm/CodeGen/AsmPrinter.h index 353733c1b0d..c1128ff0abd 100644 --- a/include/llvm/CodeGen/AsmPrinter.h +++ b/include/llvm/CodeGen/AsmPrinter.h @@ -427,11 +427,7 @@ public: /// Emit the 4-byte offset of Label from the start of its section. This can /// be done with a special directive if the target supports it (e.g. cygwin) /// or by emitting it as an offset from a label at the start of the section. - /// - /// SectionLabel is a temporary label emitted at the start of the section - /// that Label lives in. - void EmitSectionOffset(const MCSymbol *Label, - const MCSymbol *SectionLabel) const; + void emitSectionOffset(const MCSymbol *Label) const; /// Get the value for DW_AT_APPLE_isa. Zero if no isa encoding specified. virtual unsigned getISAEncoding(const Function *) { return 0; } diff --git a/include/llvm/MC/MCSection.h b/include/llvm/MC/MCSection.h index 62e1129fd78..ced53f10990 100644 --- a/include/llvm/MC/MCSection.h +++ b/include/llvm/MC/MCSection.h @@ -21,6 +21,7 @@ namespace llvm { class MCAsmInfo; class MCExpr; +class MCSymbol; class raw_ostream; /// Instances of this class represent a uniqued identifier for a section in the @@ -33,8 +34,11 @@ private: MCSection(const MCSection &) = delete; void operator=(const MCSection &) = delete; + mutable const MCSymbol *Begin; + protected: - MCSection(SectionVariant V, SectionKind K) : Variant(V), Kind(K) {} + MCSection(SectionVariant V, SectionKind K) + : Begin(nullptr), Variant(V), Kind(K) {} SectionVariant Variant; SectionKind Kind; @@ -45,6 +49,13 @@ public: SectionVariant getVariant() const { return Variant; } + const MCSymbol *getBeginSymbol() const { return Begin; } + + void setBeginSymbol(const MCSymbol &L) const { + assert(!Begin); + Begin = &L; + } + virtual void PrintSwitchToSection(const MCAsmInfo &MAI, raw_ostream &OS, const MCExpr *Subsection) const = 0; diff --git a/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp b/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp index 155aade65e1..9de36da51a0 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp +++ b/lib/CodeGen/AsmPrinter/AsmPrinterDwarf.cpp @@ -163,20 +163,13 @@ void AsmPrinter::EmitTTypeReference(const GlobalValue *GV, /// /// SectionLabel is a temporary label emitted at the start of the section that /// Label lives in. -void AsmPrinter::EmitSectionOffset(const MCSymbol *Label, - const MCSymbol *SectionLabel) const { +void AsmPrinter::emitSectionOffset(const MCSymbol *Label) const { // On COFF targets, we have to emit the special .secrel32 directive. if (MAI->needsDwarfSectionOffsetDirective()) { OutStreamer.EmitCOFFSecRel32(Label); return; } - // If Label has already been emitted, verify that it is in the same section as - // section label for sanity. - assert((!Label->isInSection() || - &Label->getSection() == &SectionLabel->getSection()) && - "Section offset using wrong section base for label"); - // If the format uses relocations with dwarf, refer to the symbol directly. if (MAI->doesDwarfUseRelocationsAcrossSections()) { OutStreamer.EmitSymbolValue(Label, 4); @@ -184,7 +177,7 @@ void AsmPrinter::EmitSectionOffset(const MCSymbol *Label, } // Otherwise, emit it as a label difference from the start of the section. - EmitLabelDifference(Label, SectionLabel, 4); + EmitLabelDifference(Label, Label->getSection().getBeginSymbol(), 4); } /// EmitDwarfRegOp - Emit dwarf register operation. diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp index 860293bb9f6..fe99c5c1c7f 100644 --- a/lib/CodeGen/AsmPrinter/DIE.cpp +++ b/lib/CodeGen/AsmPrinter/DIE.cpp @@ -588,9 +588,9 @@ void DIELocList::EmitValue(const AsmPrinter *AP, dwarf::Form Form) const { MCSymbol *Label = DD->getDebugLocEntries()[Index].Label; if (AP->MAI->doesDwarfUseRelocationsAcrossSections() && !DD->useSplitDwarf()) - AP->EmitSectionOffset(Label, DD->getDebugLocSym()); + AP->emitSectionOffset(Label); else - AP->EmitLabelDifference(Label, DD->getDebugLocSym(), 4); + AP->EmitLabelDifference(Label, Label->getSection().getBeginSymbol(), 4); } #ifndef NDEBUG diff --git a/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp b/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp index c19325952b1..dd509c402f6 100644 --- a/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp @@ -180,7 +180,7 @@ void DwarfAccelTable::EmitHashes(AsmPrinter *Asm) { // element in each bucket. This is done via a symbol subtraction from the // beginning of the section. The non-section symbol will be output later // when we emit the actual data. -void DwarfAccelTable::EmitOffsets(AsmPrinter *Asm, MCSymbol *SecBegin) { +void DwarfAccelTable::emitOffsets(AsmPrinter *Asm, const MCSymbol *SecBegin) { uint64_t PrevHash = UINT64_MAX; for (size_t i = 0, e = Buckets.size(); i < e; ++i) { for (HashList::const_iterator HI = Buckets[i].begin(), @@ -203,8 +203,7 @@ void DwarfAccelTable::EmitOffsets(AsmPrinter *Asm, MCSymbol *SecBegin) { // Walk through the buckets and emit the full data for each element in // the bucket. For the string case emit the dies and the various offsets. // Terminate each HashData bucket with 0. -void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D, - MCSymbol *StrSym) { +void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D) { for (size_t i = 0, e = Buckets.size(); i < e; ++i) { uint64_t PrevHash = UINT64_MAX; for (HashList::const_iterator HI = Buckets[i].begin(), @@ -217,7 +216,7 @@ void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D, // Remember to emit the label for our offset. Asm->OutStreamer.EmitLabel((*HI)->Sym); Asm->OutStreamer.AddComment((*HI)->Str); - Asm->EmitSectionOffset((*HI)->Data.StrSym, StrSym); + Asm->emitSectionOffset((*HI)->Data.StrSym); Asm->OutStreamer.AddComment("Num DIEs"); Asm->EmitInt32((*HI)->Data.Values.size()); for (HashDataContents *HD : (*HI)->Data.Values) { @@ -241,8 +240,8 @@ void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D, } // Emit the entire data structure to the output file. -void DwarfAccelTable::Emit(AsmPrinter *Asm, MCSymbol *SecBegin, DwarfDebug *D, - MCSymbol *StrSym) { +void DwarfAccelTable::emit(AsmPrinter *Asm, const MCSymbol *SecBegin, + DwarfDebug *D) { // Emit the header. EmitHeader(Asm); @@ -253,10 +252,10 @@ void DwarfAccelTable::Emit(AsmPrinter *Asm, MCSymbol *SecBegin, DwarfDebug *D, EmitHashes(Asm); // Emit the offsets. - EmitOffsets(Asm, SecBegin); + emitOffsets(Asm, SecBegin); // Emit the hash data. - EmitData(Asm, D, StrSym); + EmitData(Asm, D); } #ifndef NDEBUG diff --git a/lib/CodeGen/AsmPrinter/DwarfAccelTable.h b/lib/CodeGen/AsmPrinter/DwarfAccelTable.h index 74963da2cd0..e6fdf08b364 100644 --- a/lib/CodeGen/AsmPrinter/DwarfAccelTable.h +++ b/lib/CodeGen/AsmPrinter/DwarfAccelTable.h @@ -222,8 +222,8 @@ private: void EmitHeader(AsmPrinter *); void EmitBuckets(AsmPrinter *); void EmitHashes(AsmPrinter *); - void EmitOffsets(AsmPrinter *, MCSymbol *); - void EmitData(AsmPrinter *, DwarfDebug *D, MCSymbol *StrSym); + void emitOffsets(AsmPrinter *, const MCSymbol *); + void EmitData(AsmPrinter *, DwarfDebug *D); // Allocator for HashData and HashDataContents. BumpPtrAllocator Allocator; @@ -248,7 +248,7 @@ public: void AddName(StringRef Name, MCSymbol *StrSym, const DIE *Die, char Flags = 0); void FinalizeTable(AsmPrinter *, StringRef); - void Emit(AsmPrinter *, MCSymbol *, DwarfDebug *, MCSymbol *StrSym); + void emit(AsmPrinter *, const MCSymbol *, DwarfDebug *); #ifndef NDEBUG void print(raw_ostream &O); void dump() { print(dbgs()); } diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp index 85649492e23..85a6f117caa 100644 --- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp @@ -19,7 +19,7 @@ DwarfCompileUnit::DwarfCompileUnit(unsigned UID, DICompileUnit Node, AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU) : DwarfUnit(UID, dwarf::DW_TAG_compile_unit, Node, A, DW, DWU), - Skeleton(nullptr), LabelBegin(nullptr), BaseAddress(nullptr) { + Skeleton(nullptr), BaseAddress(nullptr) { insertDIE(Node, &getUnitDie()); } @@ -245,7 +245,7 @@ void DwarfCompileUnit::addSectionLabel(DIE &Die, dwarf::Attribute Attribute, addSectionDelta(Die, Attribute, Label, Sec); } -void DwarfCompileUnit::initStmtList(MCSymbol *DwarfLineSectionSym) { +void DwarfCompileUnit::initStmtList() { // Define start line table label for each Compile Unit. MCSymbol *LineTableStartSym = Asm->OutStreamer.getDwarfLineTableSymbol(getUniqueID()); @@ -257,8 +257,9 @@ void DwarfCompileUnit::initStmtList(MCSymbol *DwarfLineSectionSym) { // left in the skeleton CU and so not included. // The line table entries are not always emitted in assembly, so it // is not okay to use line_table_start here. + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); addSectionLabel(UnitDie, dwarf::DW_AT_stmt_list, LineTableStartSym, - DwarfLineSectionSym); + TLOF.getDwarfLineSection()->getBeginSymbol()); } void DwarfCompileUnit::applyStmtList(DIE &D) { @@ -380,9 +381,12 @@ void DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute, void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE, SmallVector Range) { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + // Emit offset in .debug_range as a relocatable label. emitDIE will handle // emitting it appropriately. - auto *RangeSectionSym = DD->getRangeSectionSym(); + const MCSymbol *RangeSectionSym = + TLOF.getDwarfRangesSection()->getBeginSymbol(); RangeSpanList List( Asm->GetTempSymbol("debug_ranges", DD->getNextRangeNumber()), @@ -711,14 +715,14 @@ void DwarfCompileUnit::collectDeadVariables(DISubprogram SP) { } } -void DwarfCompileUnit::emitHeader(const MCSymbol *ASectionSym) { +void DwarfCompileUnit::emitHeader(bool UseOffsets) { // Don't bother labeling the .dwo unit, as its offset isn't used. if (!Skeleton) { LabelBegin = Asm->createTempSymbol("cu_begin", getUniqueID()); Asm->OutStreamer.EmitLabel(LabelBegin); } - DwarfUnit::emitHeader(ASectionSym); + DwarfUnit::emitHeader(UseOffsets); } /// addGlobalName - Add a new global name to the compile unit. diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h index b847405f877..9484bb6f33d 100644 --- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h +++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h @@ -36,9 +36,6 @@ class DwarfCompileUnit : public DwarfUnit { /// Skeleton unit associated with this unit. DwarfCompileUnit *Skeleton; - /// A label at the start of the non-dwo section related to this unit. - MCSymbol *SectionSym; - /// The start of the unit within its section. MCSymbol *LabelBegin; @@ -76,7 +73,7 @@ public: return Skeleton; } - void initStmtList(MCSymbol *DwarfLineSectionSym); + void initStmtList(); /// Apply the DW_AT_stmt_list from this compile unit to the specified DIE. void applyStmtList(DIE &D); @@ -168,17 +165,9 @@ public: /// Set the skeleton unit associated with this unit. void setSkeleton(DwarfCompileUnit &Skel) { Skeleton = &Skel; } - MCSymbol *getSectionSym() const { + const MCSymbol *getSectionSym() const { assert(Section); - return SectionSym; - } - - /// Pass in the SectionSym even though we could recreate it in every compile - /// unit (type units will have actually distinct symbols once they're in - /// comdat sections). - void initSection(const MCSection *Section, MCSymbol *SectionSym) { - DwarfUnit::initSection(Section); - this->SectionSym = SectionSym; + return Section->getBeginSymbol(); } unsigned getLength() { @@ -186,7 +175,7 @@ public: getHeaderSize() + UnitDie.getSize(); } - void emitHeader(const MCSymbol *ASectionSym) override; + void emitHeader(bool UseOffsets) override; MCSymbol *getLabelBegin() const { assert(Section); diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index f696364cc73..24e26f90212 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -202,11 +202,6 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) dwarf::DW_FORM_data4)), AccelTypes(TypeAtoms) { - DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr; - DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr; - DwarfLineSectionSym = nullptr; - DwarfAddrSectionSym = nullptr; - DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr; CurFn = nullptr; CurMI = nullptr; @@ -248,12 +243,12 @@ DwarfDebug::~DwarfDebug() { } // Switch to the specified MCSection and emit an assembler // temporary label to it if SymbolStem is specified. -static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, - const char *SymbolStem) { +static void emitSectionSym(AsmPrinter *Asm, const MCSection *Section, + StringRef SymbolStem) { Asm->OutStreamer.SwitchSection(Section); MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); Asm->OutStreamer.EmitLabel(TmpSym); - return TmpSym; + Section->setBeginSymbol(*TmpSym); } static bool isObjCClass(StringRef Name) { @@ -401,7 +396,7 @@ DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) { NewCU.addString(Die, dwarf::DW_AT_name, FN); if (!useSplitDwarf()) { - NewCU.initStmtList(DwarfLineSectionSym); + 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. @@ -423,11 +418,9 @@ DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) { dwarf::DW_FORM_data1, RVer); if (useSplitDwarf()) - NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(), - DwarfInfoDWOSectionSym); + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection()); else - NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(), - DwarfInfoSectionSym); + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection()); CUMap.insert(std::make_pair(DIUnit, &NewCU)); CUDieMap.insert(std::make_pair(&Die, &NewCU)); @@ -557,6 +550,8 @@ void DwarfDebug::collectDeadVariables() { } void DwarfDebug::finalizeModuleInfo() { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + finishSubprogramDefinitions(); finishVariableDefinitions(); @@ -586,13 +581,16 @@ void DwarfDebug::finalizeModuleInfo() { // We don't keep track of which addresses are used in which CU so this // is a bit pessimistic under LTO. - if (!AddrPool.isEmpty()) + if (!AddrPool.isEmpty()) { + const MCSymbol *Sym = TLOF.getDwarfAddrSection()->getBeginSymbol(); SkCU->addSectionLabel(SkCU->getUnitDie(), dwarf::DW_AT_GNU_addr_base, - DwarfAddrSectionSym, DwarfAddrSectionSym); - if (!SkCU->getRangeLists().empty()) + Sym, Sym); + } + if (!SkCU->getRangeLists().empty()) { + const MCSymbol *Sym = TLOF.getDwarfRangesSection()->getBeginSymbol(); SkCU->addSectionLabel(SkCU->getUnitDie(), dwarf::DW_AT_GNU_ranges_base, - DwarfDebugRangeSectionSym, - DwarfDebugRangeSectionSym); + Sym, Sym); + } } // If we have code split among multiple sections or non-contiguous @@ -623,13 +621,14 @@ void DwarfDebug::finalizeModuleInfo() { // Emit all Dwarf sections that should come after the content. void DwarfDebug::endModule() { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 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 (!DwarfInfoSectionSym) + if (!TLOF.getDwarfInfoSection()->getBeginSymbol()) return; // Finalize the debug info for the module. @@ -637,6 +636,12 @@ void DwarfDebug::endModule() { emitDebugStr(); + if (useSplitDwarf()) + emitDebugLocDWO(); + else + // Emit info into a debug loc section. + emitDebugLoc(); + // Emit all the DIEs into a debug info section. emitDebugInfo(); @@ -655,12 +660,9 @@ void DwarfDebug::endModule() { emitDebugInfoDWO(); emitDebugAbbrevDWO(); emitDebugLineDWO(); - emitDebugLocDWO(); // Emit DWO addresses. AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection()); - } else - // Emit info into a debug loc section. - emitDebugLoc(); + } // Emit info into the dwarf accelerator table sections. if (useDwarfAccelTables()) { @@ -1304,43 +1306,30 @@ void DwarfDebug::emitSectionLabels() { const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); // Dwarf sections base addresses. - DwarfInfoSectionSym = - emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); + emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); if (useSplitDwarf()) { - DwarfInfoDWOSectionSym = - emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo"); - DwarfTypesDWOSectionSym = emitSectionSym( - Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo"); + emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo"); + emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo"); } - DwarfAbbrevSectionSym = - emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); + emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); if (useSplitDwarf()) - DwarfAbbrevDWOSectionSym = emitSectionSym( - Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo"); + emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo"); - DwarfLineSectionSym = - emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); - DwarfStrSectionSym = - emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); + emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); + emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); if (useSplitDwarf()) { - DwarfStrDWOSectionSym = - emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); - DwarfAddrSectionSym = - emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); - DwarfDebugLocSectionSym = - emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc"); + emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); + emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); + emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc"); } else - DwarfDebugLocSectionSym = - emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc"); - DwarfDebugRangeSectionSym = - emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range"); + emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc"); + emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range"); } // Emit the debug info section. void DwarfDebug::emitDebugInfo() { DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; - - Holder.emitUnits(DwarfAbbrevSectionSym); + Holder.emitUnits(/* UseOffsets */ false); } // Emit the abbreviation section. @@ -1377,12 +1366,10 @@ void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { void DwarfDebug::emitAccel(DwarfAccelTable &Accel, const MCSection *Section, StringRef TableName, StringRef SymName) { Accel.FinalizeTable(Asm, TableName); - Asm->OutStreamer.SwitchSection(Section); - auto *SectionBegin = Asm->GetTempSymbol(SymName); - Asm->OutStreamer.EmitLabel(SectionBegin); + emitSectionSym(Asm, Section, SymName); // Emit the full data. - Accel.Emit(Asm, SectionBegin, this, DwarfStrSectionSym); + Accel.emit(Asm, Section->getBeginSymbol(), this); } // Emit visible names into a hashed accelerator table section. @@ -1508,7 +1495,7 @@ void DwarfDebug::emitDebugPubSection( Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); - Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym()); + Asm->emitSectionOffset(TheU->getLabelBegin()); Asm->OutStreamer.AddComment("Compilation Unit Length"); Asm->EmitInt32(TheU->getLength()); @@ -1856,7 +1843,7 @@ void DwarfDebug::emitDebugARanges() { Asm->OutStreamer.AddComment("DWARF Arange version number"); Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); - Asm->EmitSectionOffset(CU->getLabelBegin(), CU->getSectionSym()); + Asm->emitSectionOffset(CU->getLabelBegin()); Asm->OutStreamer.AddComment("Address Size (in bytes)"); Asm->EmitInt8(PtrSize); Asm->OutStreamer.AddComment("Segment Size (in bytes)"); @@ -1952,10 +1939,9 @@ DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) { auto OwnedUnit = make_unique( CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder); DwarfCompileUnit &NewCU = *OwnedUnit; - NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(), - DwarfInfoSectionSym); + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection()); - NewCU.initStmtList(DwarfLineSectionSym); + NewCU.initStmtList(); initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit)); @@ -1966,9 +1952,8 @@ DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) { // compile units that would normally be in debug_info. void DwarfDebug::emitDebugInfoDWO() { assert(useSplitDwarf() && "No split dwarf debug info?"); - // Don't pass an abbrev symbol, using a constant zero instead so as not to - // emit relocations into the dwo file. - InfoHolder.emitUnits(/* AbbrevSymbol */ nullptr); + // Don't emit relocations into the dwo file. + InfoHolder.emitUnits(/* UseOffsets */ true); } // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h index 41e86c63987..757e8783d0b 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.h +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h @@ -243,16 +243,6 @@ class DwarfDebug : public AsmPrinterHandler { // If nonnull, stores the CU in which the previous subprogram was contained. const DwarfCompileUnit *PrevCU; - // Section Symbols: these are assembler temporary labels that are emitted at - // the beginning of each supported dwarf section. These are used to form - // section offsets and are created by EmitSectionLabels. - MCSymbol *DwarfInfoSectionSym, *DwarfAbbrevSectionSym; - MCSymbol *DwarfStrSectionSym, *TextSectionSym, *DwarfDebugRangeSectionSym; - MCSymbol *DwarfDebugLocSectionSym, *DwarfLineSectionSym, *DwarfAddrSectionSym; - MCSymbol *DwarfInfoDWOSectionSym, *DwarfAbbrevDWOSectionSym; - MCSymbol *DwarfTypesDWOSectionSym; - MCSymbol *DwarfStrDWOSectionSym; - // As an optimization, there is no need to emit an entry in the directory // table for the same directory as DW_AT_comp_dir. StringRef CompilationDir; @@ -559,15 +549,6 @@ public: /// Returns the Dwarf Version. unsigned getDwarfVersion() const { return DwarfVersion; } - /// Returns the section symbol for the .debug_loc section. - MCSymbol *getDebugLocSym() const { return DwarfDebugLocSectionSym; } - - /// Returns the section symbol for the .debug_str section. - MCSymbol *getDebugStrSym() const { return DwarfStrSectionSym; } - - /// Returns the section symbol for the .debug_ranges section. - MCSymbol *getRangeSectionSym() const { return DwarfDebugRangeSectionSym; } - /// Returns the previous CU that was being updated const DwarfCompileUnit *getPrevCU() const { return PrevCU; } void setPrevCU(const DwarfCompileUnit *PrevCU) { this->PrevCU = PrevCU; } diff --git a/lib/CodeGen/AsmPrinter/DwarfFile.cpp b/lib/CodeGen/AsmPrinter/DwarfFile.cpp index 7eceec3cf2b..60acc58e787 100644 --- a/lib/CodeGen/AsmPrinter/DwarfFile.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfFile.cpp @@ -47,13 +47,13 @@ void DwarfFile::addUnit(std::unique_ptr U) { // Emit the various dwarf units to the unit section USection with // the abbreviations going into ASection. -void DwarfFile::emitUnits(const MCSymbol *ASectionSym) { +void DwarfFile::emitUnits(bool UseOffsets) { for (const auto &TheU : CUs) { DIE &Die = TheU->getUnitDie(); const MCSection *USection = TheU->getSection(); Asm->OutStreamer.SwitchSection(USection); - TheU->emitHeader(ASectionSym); + TheU->emitHeader(UseOffsets); Asm->emitDwarfDIE(Die); } diff --git a/lib/CodeGen/AsmPrinter/DwarfFile.h b/lib/CodeGen/AsmPrinter/DwarfFile.h index 68f2293b036..c9de6665b01 100644 --- a/lib/CodeGen/AsmPrinter/DwarfFile.h +++ b/lib/CodeGen/AsmPrinter/DwarfFile.h @@ -80,7 +80,7 @@ public: /// \brief Emit all of the units to the section listed with the given /// abbreviation section. - void emitUnits(const MCSymbol *ASectionSym); + void emitUnits(bool UseOffsets); /// \brief Emit a set of abbreviations to the specific section. void emitAbbrevs(const MCSection *); diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp index 7940348efca..a65136b485f 100644 --- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp @@ -264,12 +264,14 @@ void DwarfUnit::addIndexedString(DIE &Die, dwarf::Attribute Attribute, /// to be in the local string pool instead of indirected. void DwarfUnit::addLocalString(DIE &Die, dwarf::Attribute Attribute, StringRef String) { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); MCSymbol *Symb = DU->getStringPool().getSymbol(*Asm, String); DIEValue *Value; if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) Value = new (DIEValueAllocator) DIELabel(Symb); else - Value = new (DIEValueAllocator) DIEDelta(Symb, DD->getDebugStrSym()); + Value = new (DIEValueAllocator) + DIEDelta(Symb, TLOF.getDwarfStrSection()->getBeginSymbol()); DIEValue *Str = new (DIEValueAllocator) DIEString(Value, String); Die.addValue(Attribute, dwarf::DW_FORM_strp, Str); } @@ -1604,7 +1606,7 @@ DIE *DwarfUnit::getOrCreateStaticMemberDIE(DIDerivedType DT) { return &StaticMemberDIE; } -void DwarfUnit::emitHeader(const MCSymbol *ASectionSym) { +void DwarfUnit::emitHeader(bool UseOffsets) { // Emit size of content not including length itself Asm->OutStreamer.AddComment("Length of Unit"); Asm->EmitInt32(getHeaderSize() + UnitDie.getSize()); @@ -1612,14 +1614,16 @@ void DwarfUnit::emitHeader(const MCSymbol *ASectionSym) { Asm->OutStreamer.AddComment("DWARF version number"); Asm->EmitInt16(DD->getDwarfVersion()); Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); + // We share one abbreviations table across all units so it's always at the // start of the section. Use a relocatable offset where needed to ensure // linking doesn't invalidate that offset. - if (ASectionSym) - Asm->EmitSectionOffset(ASectionSym, ASectionSym); + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + if (!UseOffsets) + Asm->emitSectionOffset(TLOF.getDwarfAbbrevSection()->getBeginSymbol()); else - // Use a constant value when no symbol is provided. Asm->EmitInt32(0); + Asm->OutStreamer.AddComment("Address Size (in bytes)"); Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); } @@ -1629,8 +1633,8 @@ void DwarfUnit::initSection(const MCSection *Section) { this->Section = Section; } -void DwarfTypeUnit::emitHeader(const MCSymbol *ASectionSym) { - DwarfUnit::emitHeader(ASectionSym); +void DwarfTypeUnit::emitHeader(bool UseOffsets) { + DwarfUnit::emitHeader(UseOffsets); Asm->OutStreamer.AddComment("Type Signature"); Asm->OutStreamer.EmitIntValue(TypeSignature, sizeof(TypeSignature)); Asm->OutStreamer.AddComment("Type DIE Offset"); diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.h b/lib/CodeGen/AsmPrinter/DwarfUnit.h index ea15ab025f7..c700b2a10b8 100644 --- a/lib/CodeGen/AsmPrinter/DwarfUnit.h +++ b/lib/CodeGen/AsmPrinter/DwarfUnit.h @@ -120,7 +120,6 @@ protected: DwarfUnit(unsigned UID, dwarf::Tag, DICompileUnit CU, AsmPrinter *A, DwarfDebug *DW, DwarfFile *DWU); - void initSection(const MCSection *Section); /// Add a string attribute data and value. void addLocalString(DIE &Die, dwarf::Attribute Attribute, StringRef Str); @@ -132,6 +131,8 @@ protected: public: virtual ~DwarfUnit(); + void initSection(const MCSection *Section); + const MCSection *getSection() const { assert(Section); return Section; @@ -321,7 +322,7 @@ public: } /// Emit the header for this unit, not including the initial length field. - virtual void emitHeader(const MCSymbol *ASectionSym); + virtual void emitHeader(bool UseOffsets); virtual DwarfCompileUnit &getCU() = 0; @@ -423,12 +424,11 @@ public: void setType(const DIE *Ty) { this->Ty = Ty; } /// Emit the header for this unit, not including the initial length field. - void emitHeader(const MCSymbol *ASectionSym) override; + void emitHeader(bool UseOffsets) override; unsigned getHeaderSize() const override { return DwarfUnit::getHeaderSize() + sizeof(uint64_t) + // Type Signature sizeof(uint32_t); // Type DIE Offset } - using DwarfUnit::initSection; DwarfCompileUnit &getCU() override { return CU; } }; } // end llvm namespace