diff --git a/llvm/include/llvm/DebugInfo/DIContext.h b/llvm/include/llvm/DebugInfo/DIContext.h index a2c3f03ee811..679b490caf81 100644 --- a/llvm/include/llvm/DebugInfo/DIContext.h +++ b/llvm/include/llvm/DebugInfo/DIContext.h @@ -101,6 +101,7 @@ enum DIDumpType { DIDT_Abbrev, DIDT_AbbrevDwo, DIDT_Aranges, + DIDT_Frames, DIDT_Info, DIDT_InfoDwo, DIDT_Line, diff --git a/llvm/include/llvm/Support/Dwarf.h b/llvm/include/llvm/Support/Dwarf.h index c703da5762f9..b52914f93851 100644 --- a/llvm/include/llvm/Support/Dwarf.h +++ b/llvm/include/llvm/Support/Dwarf.h @@ -16,6 +16,9 @@ #ifndef LLVM_SUPPORT_DWARF_H #define LLVM_SUPPORT_DWARF_H +#include "llvm/Support/DataTypes.h" + + namespace llvm { //===----------------------------------------------------------------------===// @@ -53,10 +56,16 @@ enum llvm_dwarf_constants { DW_TAG_user_base = 0x1000, // Recommended base for user tags. - DW_CIE_VERSION = 1, // Common frame information version. - DW_CIE_ID = 0xffffffff // Common frame information mark. + DW_CIE_VERSION = 1 // Common frame information version. }; + +// Special ID values that distinguish a CIE from a FDE in DWARF CFI. +// Not inside an enum because a 64-bit value is needed. +const uint32_t DW_CIE_ID = UINT32_MAX; +const uint64_t DW64_CIE_ID = UINT64_MAX; + + enum dwarf_constants { DWARF_VERSION = 2, diff --git a/llvm/lib/DebugInfo/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARFContext.cpp index 768427fab07a..d061f4e1f8ed 100644 --- a/llvm/lib/DebugInfo/DWARFContext.cpp +++ b/llvm/lib/DebugInfo/DWARFContext.cpp @@ -31,6 +31,11 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) { getCompileUnitAtIndex(i)->dump(OS); } + if (DumpType == DIDT_All || DumpType == DIDT_Frames) { + OS << "\n.debug_frame contents:\n"; + getDebugFrame()->dump(OS); + } + uint32_t offset = 0; if (DumpType == DIDT_All || DumpType == DIDT_Aranges) { OS << "\n.debug_aranges contents:\n"; @@ -152,6 +157,26 @@ const DWARFDebugAranges *DWARFContext::getDebugAranges() { return Aranges.get(); } +const DWARFDebugFrame *DWARFContext::getDebugFrame() { + if (DebugFrame) + return DebugFrame.get(); + + // There's a "bug" in the DWARFv3 standard with respect to the target address + // size within debug frame sections. While DWARF is supposed to be independent + // of its container, FDEs have fields with size being "target address size", + // which isn't specified in DWARF in general. It's only specified for CUs, but + // .eh_frame can appear without a .debug_info section. Follow the example of + // other tools (libdwarf) and extract this from the container (ObjectFile + // provides this information). This problem is fixed in DWARFv4 + // See this dwarf-discuss discussion for more details: + // http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html + DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(), + getAddressSize()); + DebugFrame.reset(new DWARFDebugFrame()); + DebugFrame->parse(debugFrameData); + return DebugFrame.get(); +} + const DWARFLineTable * DWARFContext::getLineTableForCompileUnit(DWARFCompileUnit *cu) { if (!Line) @@ -440,7 +465,8 @@ DIInliningInfo DWARFContext::getInliningInfoForAddress(uint64_t Address, } DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) : - IsLittleEndian(Obj->isLittleEndian()) { + IsLittleEndian(Obj->isLittleEndian()), + AddressSize(Obj->getBytesInAddress()) { error_code ec; for (object::section_iterator i = Obj->begin_sections(), e = Obj->end_sections(); @@ -459,6 +485,8 @@ DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) : LineSection = data; else if (name == "debug_aranges") ARangeSection = data; + else if (name == "debug_frame") + DebugFrameSection = data; else if (name == "debug_str") StringSection = data; else if (name == "debug_ranges") { diff --git a/llvm/lib/DebugInfo/DWARFContext.h b/llvm/lib/DebugInfo/DWARFContext.h index 9ff094bd484d..f12a05479be5 100644 --- a/llvm/lib/DebugInfo/DWARFContext.h +++ b/llvm/lib/DebugInfo/DWARFContext.h @@ -12,6 +12,7 @@ #include "DWARFCompileUnit.h" #include "DWARFDebugAranges.h" +#include "DWARFDebugFrame.h" #include "DWARFDebugLine.h" #include "DWARFDebugRangeList.h" #include "llvm/ADT/OwningPtr.h" @@ -29,6 +30,7 @@ class DWARFContext : public DIContext { OwningPtr Abbrev; OwningPtr Aranges; OwningPtr Line; + OwningPtr DebugFrame; SmallVector DWOCUs; OwningPtr AbbrevDWO; @@ -84,6 +86,9 @@ public: /// Get a pointer to the parsed DebugAranges object. const DWARFDebugAranges *getDebugAranges(); + /// Get a pointer to the parsed frame information object. + const DWARFDebugFrame *getDebugFrame(); + /// Get a pointer to a parsed line table corresponding to a compile unit. const DWARFDebugLine::LineTable * getLineTableForCompileUnit(DWARFCompileUnit *cu); @@ -96,11 +101,13 @@ public: DILineInfoSpecifier Specifier = DILineInfoSpecifier()); virtual bool isLittleEndian() const = 0; + virtual uint8_t getAddressSize() const = 0; virtual const RelocAddrMap &infoRelocMap() const = 0; virtual const RelocAddrMap &lineRelocMap() const = 0; virtual StringRef getInfoSection() = 0; virtual StringRef getAbbrevSection() = 0; virtual StringRef getARangeSection() = 0; + virtual StringRef getDebugFrameSection() = 0; virtual StringRef getLineSection() = 0; virtual StringRef getStringSection() = 0; virtual StringRef getRangeSection() = 0; @@ -132,11 +139,13 @@ private: class DWARFContextInMemory : public DWARFContext { virtual void anchor(); bool IsLittleEndian; + uint8_t AddressSize; RelocAddrMap InfoRelocMap; RelocAddrMap LineRelocMap; StringRef InfoSection; StringRef AbbrevSection; StringRef ARangeSection; + StringRef DebugFrameSection; StringRef LineSection; StringRef StringSection; StringRef RangeSection; @@ -153,11 +162,13 @@ class DWARFContextInMemory : public DWARFContext { public: DWARFContextInMemory(object::ObjectFile *); virtual bool isLittleEndian() const { return IsLittleEndian; } + virtual uint8_t getAddressSize() const { return AddressSize; } virtual const RelocAddrMap &infoRelocMap() const { return InfoRelocMap; } virtual const RelocAddrMap &lineRelocMap() const { return LineRelocMap; } virtual StringRef getInfoSection() { return InfoSection; } virtual StringRef getAbbrevSection() { return AbbrevSection; } virtual StringRef getARangeSection() { return ARangeSection; } + virtual StringRef getDebugFrameSection() { return DebugFrameSection; } virtual StringRef getLineSection() { return LineSection; } virtual StringRef getStringSection() { return StringSection; } virtual StringRef getRangeSection() { return RangeSection; } diff --git a/llvm/lib/DebugInfo/DWARFDebugFrame.cpp b/llvm/lib/DebugInfo/DWARFDebugFrame.cpp new file mode 100644 index 000000000000..0b78cce1dd3b --- /dev/null +++ b/llvm/lib/DebugInfo/DWARFDebugFrame.cpp @@ -0,0 +1,195 @@ +//===-- DWARFDebugFrame.h - Parsing of .debug_frame -------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "DWARFDebugFrame.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/Support/DataTypes.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/Format.h" + +using namespace llvm; +using namespace dwarf; + + +class llvm::FrameEntry { +public: + enum FrameKind {FK_CIE, FK_FDE}; + FrameEntry(FrameKind K, DataExtractor D, uint64_t Offset, uint64_t Length) + : Kind(K), Data(D), Offset(Offset), Length(Length) + {} + + FrameKind getKind() const { return Kind; } + + virtual void dumpHeader(raw_ostream &OS) const = 0; +protected: + const FrameKind Kind; + DataExtractor Data; + uint64_t Offset; + uint64_t Length; +}; + + +class CIE : public FrameEntry { +public: + // CIEs (and FDEs) are simply container classes, so the only sensible way to + // create them is by providing the full parsed contents in the constructor. + CIE(DataExtractor D, uint64_t Offset, uint64_t Length, uint8_t Version, + SmallString<8> Augmentation, uint64_t CodeAlignmentFactor, + int64_t DataAlignmentFactor, uint64_t ReturnAddressRegister) + : FrameEntry(FK_CIE, D, Offset, Length), Version(Version), + Augmentation(Augmentation), CodeAlignmentFactor(CodeAlignmentFactor), + DataAlignmentFactor(DataAlignmentFactor), + ReturnAddressRegister(ReturnAddressRegister) + {} + + void dumpHeader(raw_ostream &OS) const { + OS << format("%08x %08x %08x CIE", Offset, Length, DW_CIE_ID) << "\n"; + OS << format(" Version: %d\n", Version); + OS << " Augmentation: \"" << Augmentation << "\"\n"; + OS << format(" Code alignment factor: %u\n", CodeAlignmentFactor); + OS << format(" Data alignment factor: %d\n", DataAlignmentFactor); + OS << format(" Return address column: %d\n", ReturnAddressRegister); + OS << "\n"; + } + + static bool classof(const FrameEntry *FE) { + return FE->getKind() == FK_CIE; + } +private: + uint8_t Version; + SmallString<8> Augmentation; + uint64_t CodeAlignmentFactor; + int64_t DataAlignmentFactor; + uint64_t ReturnAddressRegister; +}; + + +class FDE : public FrameEntry { +public: + // Each FDE has a CIE it's "linked to". Our FDE contains is constructed with + // an offset to the CIE (provided by parsing the FDE header). The CIE itself + // is obtained lazily once it's actually required. + FDE(DataExtractor D, uint64_t Offset, uint64_t Length, int64_t LinkedCIEOffset, + uint64_t InitialLocation, uint64_t AddressRange) + : FrameEntry(FK_FDE, D, Offset, Length), LinkedCIEOffset(LinkedCIEOffset), + InitialLocation(InitialLocation), AddressRange(AddressRange), + LinkedCIE(NULL) + {} + + void dumpHeader(raw_ostream &OS) const { + OS << format("%08x %08x %08x FDE ", Offset, Length, LinkedCIEOffset); + OS << format("cie=%08x pc=%08x...%08x\n", + LinkedCIEOffset, InitialLocation, + InitialLocation + AddressRange); + OS << "\n"; + } + + static bool classof(const FrameEntry *FE) { + return FE->getKind() == FK_FDE; + } +private: + uint64_t LinkedCIEOffset; + uint64_t InitialLocation; + uint64_t AddressRange; + CIE *LinkedCIE; +}; + + +DWARFDebugFrame::DWARFDebugFrame() +{ +} + + +DWARFDebugFrame::~DWARFDebugFrame() +{ + for (EntryVector::iterator I = Entries.begin(), E = Entries.end(); + I != E; ++I) { + delete *I; + } +} + + +static void LLVM_ATTRIBUTE_UNUSED dumpDataAux(DataExtractor Data, + uint32_t Offset, int Length) { + errs() << "DUMP: "; + for (int i = 0; i < Length; ++i) { + uint8_t c = Data.getU8(&Offset); + errs().write_hex(c); errs() << " "; + } + errs() << "\n"; +} + + +void DWARFDebugFrame::parse(DataExtractor Data) { + uint32_t Offset = 0; + + while (Data.isValidOffset(Offset)) { + uint32_t StartOffset = Offset; + + bool IsDWARF64 = false; + uint64_t Length = Data.getU32(&Offset); + uint64_t Id; + + if (Length == UINT32_MAX) { + // DWARF-64 is distinguished by the first 32 bits of the initial length + // field being 0xffffffff. Then, the next 64 bits are the actual entry + // length. + IsDWARF64 = true; + Length = Data.getU64(&Offset); + } + + // At this point, Offset points to the next field after Length. + // Length is the structure size excluding itself. Compute an offset one + // past the end of the structure (needed to know how many instructions to + // read). + // TODO: For honest DWARF64 support, DataExtractor will have to treat + // offset_ptr as uint64_t* + uint32_t EndStructureOffset = Offset + static_cast(Length); + + // The Id field's size depends on the DWARF format + Id = Data.getUnsigned(&Offset, IsDWARF64 ? 8 : 4); + bool IsCIE = ((IsDWARF64 && Id == DW64_CIE_ID) || Id == DW_CIE_ID); + + if (IsCIE) { + // Note: this is specifically DWARFv3 CIE header structure. It was + // changed in DWARFv4. + uint8_t Version = Data.getU8(&Offset); + const char *Augmentation = Data.getCStr(&Offset); + uint64_t CodeAlignmentFactor = Data.getULEB128(&Offset); + int64_t DataAlignmentFactor = Data.getSLEB128(&Offset); + uint64_t ReturnAddressRegister = Data.getULEB128(&Offset); + + CIE *NewCIE = new CIE(Data, StartOffset, Length, Version, + StringRef(Augmentation), CodeAlignmentFactor, + DataAlignmentFactor, ReturnAddressRegister); + Entries.push_back(NewCIE); + } else { + // FDE + uint64_t CIEPointer = Id; + uint64_t InitialLocation = Data.getAddress(&Offset); + uint64_t AddressRange = Data.getAddress(&Offset); + + FDE *NewFDE = new FDE(Data, StartOffset, Length, CIEPointer, + InitialLocation, AddressRange); + Entries.push_back(NewFDE); + } + + Offset = EndStructureOffset; + } +} + + +void DWARFDebugFrame::dump(raw_ostream &OS) const { + OS << "\n"; + for (EntryVector::const_iterator I = Entries.begin(), E = Entries.end(); + I != E; ++I) { + (*I)->dumpHeader(OS); + } +} + diff --git a/llvm/lib/DebugInfo/DWARFDebugFrame.h b/llvm/lib/DebugInfo/DWARFDebugFrame.h new file mode 100644 index 000000000000..48b8d63a5a64 --- /dev/null +++ b/llvm/lib/DebugInfo/DWARFDebugFrame.h @@ -0,0 +1,46 @@ +//===-- DWARFDebugFrame.h - Parsing of .debug_frame -------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_DEBUGINFO_DWARFDEBUGFRAME_H +#define LLVM_DEBUGINFO_DWARFDEBUGFRAME_H + +#include "llvm/Support/DataExtractor.h" +#include "llvm/Support/raw_ostream.h" +#include + + +namespace llvm { + +class FrameEntry; + + +/// \brief A parsed .debug_frame section +/// +class DWARFDebugFrame { +public: + DWARFDebugFrame(); + ~DWARFDebugFrame(); + + /// \brief Dump the section data into the given stream. + void dump(raw_ostream &OS) const; + + /// \brief Parse the section from raw data. + /// data is assumed to be pointing to the beginning of the section. + void parse(DataExtractor Data); + +private: + typedef std::vector EntryVector; + EntryVector Entries; +}; + + +} // namespace llvm + +#endif + diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp index 6041510e039d..290f3a66185f 100644 --- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp +++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp @@ -63,6 +63,7 @@ DumpType("debug-dump", cl::init(DIDT_All), clEnumValN(DIDT_Info, "info", ".debug_info"), clEnumValN(DIDT_InfoDwo, "info.dwo", ".debug_info.dwo"), clEnumValN(DIDT_Line, "line", ".debug_line"), + clEnumValN(DIDT_Frames, "frames", ".debug_frame"), clEnumValN(DIDT_Ranges, "ranges", ".debug_ranges"), clEnumValN(DIDT_Str, "str", ".debug_str"), clEnumValN(DIDT_StrDwo, "str.dwo", ".debug_str.dwo"),