nils.hoelscher
/
llvm-for-llvmta
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
llvm-for-llvmta/unittests/DebugInfo/DWARF/DwarfGenerator.cpp

580 lines
19 KiB
C++
Raw Blame History

//===--- unittests/DebugInfo/DWARF/DwarfGenerator.cpp -----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "DwarfGenerator.h"
#include "../lib/CodeGen/AsmPrinter/DwarfStringPool.h"
#include "llvm/ADT/Triple.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/DIE.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCTargetOptionsCommandFlags.h"
#include "llvm/Pass.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
using namespace dwarf;
mc::RegisterMCTargetOptionsFlags MOF;
namespace {} // end anonymous namespace
//===----------------------------------------------------------------------===//
/// dwarfgen::DIE implementation.
//===----------------------------------------------------------------------===//
unsigned dwarfgen::DIE::computeSizeAndOffsets(unsigned Offset) {
auto &DG = CU->getGenerator();
return Die->computeOffsetsAndAbbrevs(DG.getAsmPrinter(), DG.getAbbrevSet(),
Offset);
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form, uint64_t U) {
auto &DG = CU->getGenerator();
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEInteger(U));
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form, const MCExpr &Expr) {
auto &DG = CU->getGenerator();
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEExpr(&Expr));
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form,
StringRef String) {
auto &DG = CU->getGenerator();
switch (Form) {
case DW_FORM_string:
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
new (DG.getAllocator())
DIEInlineString(String, DG.getAllocator()));
break;
case DW_FORM_strp:
Die->addValue(
DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEString(DG.getStringPool().getEntry(*DG.getAsmPrinter(), String)));
break;
case DW_FORM_GNU_str_index:
case DW_FORM_strx:
case DW_FORM_strx1:
case DW_FORM_strx2:
case DW_FORM_strx3:
case DW_FORM_strx4:
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEString(DG.getStringPool().getIndexedEntry(
*DG.getAsmPrinter(), String)));
break;
default:
llvm_unreachable("Unhandled form!");
}
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form,
dwarfgen::DIE &RefDie) {
auto &DG = CU->getGenerator();
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEEntry(*RefDie.Die));
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form, const void *P,
size_t S) {
auto &DG = CU->getGenerator();
DIEBlock *Block = new (DG.getAllocator()) DIEBlock;
for (size_t I = 0; I < S; ++I)
Block->addValue(
DG.getAllocator(), (dwarf::Attribute)0, dwarf::DW_FORM_data1,
DIEInteger(
(const_cast<uint8_t *>(static_cast<const uint8_t *>(P)))[I]));
Block->ComputeSize(DG.getAsmPrinter());
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
Block);
}
void dwarfgen::DIE::addAttribute(uint16_t A, dwarf::Form Form) {
auto &DG = CU->getGenerator();
assert(Form == DW_FORM_flag_present);
Die->addValue(DG.getAllocator(), static_cast<dwarf::Attribute>(A), Form,
DIEInteger(1));
}
void dwarfgen::DIE::addStrOffsetsBaseAttribute() {
auto &DG = CU->getGenerator();
auto &MC = *DG.getMCContext();
AsmPrinter *Asm = DG.getAsmPrinter();
const MCSymbol *SectionStart =
Asm->getObjFileLowering().getDwarfStrOffSection()->getBeginSymbol();
const MCExpr *Expr =
MCSymbolRefExpr::create(DG.getStringOffsetsStartSym(), MC);
if (!Asm->MAI->doesDwarfUseRelocationsAcrossSections())
Expr = MCBinaryExpr::createSub(
Expr, MCSymbolRefExpr::create(SectionStart, MC), MC);
addAttribute(dwarf::DW_AT_str_offsets_base, DW_FORM_sec_offset, *Expr);
}
dwarfgen::DIE dwarfgen::DIE::addChild(dwarf::Tag Tag) {
auto &DG = CU->getGenerator();
return dwarfgen::DIE(CU,
&Die->addChild(llvm::DIE::get(DG.getAllocator(), Tag)));
}
dwarfgen::DIE dwarfgen::CompileUnit::getUnitDIE() {
return dwarfgen::DIE(this, &DU.getUnitDie());
}
//===----------------------------------------------------------------------===//
/// dwarfgen::LineTable implementation.
//===----------------------------------------------------------------------===//
DWARFDebugLine::Prologue dwarfgen::LineTable::createBasicPrologue() const {
DWARFDebugLine::Prologue P;
switch (Version) {
case 2:
case 3:
P.TotalLength = 41;
P.PrologueLength = 35;
break;
case 4:
P.TotalLength = 42;
P.PrologueLength = 36;
break;
case 5:
P.TotalLength = 50;
P.PrologueLength = 42;
P.FormParams.AddrSize = AddrSize;
break;
default:
llvm_unreachable("unsupported version");
}
if (Format == DWARF64) {
P.TotalLength += 4;
P.FormParams.Format = DWARF64;
}
P.TotalLength += getContentsSize();
P.FormParams.Version = Version;
P.MinInstLength = 1;
P.MaxOpsPerInst = 1;
P.DefaultIsStmt = 1;
P.LineBase = -5;
P.LineRange = 14;
P.OpcodeBase = 13;
P.StandardOpcodeLengths = {0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1};
P.IncludeDirectories.push_back(
DWARFFormValue::createFromPValue(DW_FORM_string, "a dir"));
P.FileNames.push_back(DWARFDebugLine::FileNameEntry());
P.FileNames.back().Name =
DWARFFormValue::createFromPValue(DW_FORM_string, "a file");
return P;
}
void dwarfgen::LineTable::setPrologue(DWARFDebugLine::Prologue NewPrologue) {
Prologue = NewPrologue;
CustomPrologue.clear();
}
void dwarfgen::LineTable::setCustomPrologue(
ArrayRef<ValueAndLength> NewPrologue) {
Prologue.reset();
CustomPrologue = NewPrologue;
}
void dwarfgen::LineTable::addByte(uint8_t Value) {
Contents.push_back({Value, Byte});
}
void dwarfgen::LineTable::addStandardOpcode(uint8_t Opcode,
ArrayRef<ValueAndLength> Operands) {
Contents.push_back({Opcode, Byte});
Contents.insert(Contents.end(), Operands.begin(), Operands.end());
}
void dwarfgen::LineTable::addExtendedOpcode(uint64_t Length, uint8_t Opcode,
ArrayRef<ValueAndLength> Operands) {
Contents.push_back({0, Byte});
Contents.push_back({Length, ULEB});
Contents.push_back({Opcode, Byte});
Contents.insert(Contents.end(), Operands.begin(), Operands.end());
}
void dwarfgen::LineTable::generate(MCContext &MC, AsmPrinter &Asm) const {
MC.setDwarfVersion(Version);
MCSymbol *EndSymbol = nullptr;
if (!CustomPrologue.empty()) {
writeData(CustomPrologue, Asm);
} else if (!Prologue) {
EndSymbol = writeDefaultPrologue(Asm);
} else {
writePrologue(Asm);
}
writeData(Contents, Asm);
if (EndSymbol != nullptr)
Asm.OutStreamer->emitLabel(EndSymbol);
}
void dwarfgen::LineTable::writeData(ArrayRef<ValueAndLength> Data,
AsmPrinter &Asm) const {
for (auto Entry : Data) {
switch (Entry.Length) {
case Byte:
case Half:
case Long:
case Quad:
Asm.OutStreamer->emitIntValue(Entry.Value, Entry.Length);
continue;
case ULEB:
Asm.emitULEB128(Entry.Value);
continue;
case SLEB:
Asm.emitSLEB128(Entry.Value);
continue;
}
llvm_unreachable("unsupported ValueAndLength Length value");
}
}
size_t dwarfgen::LineTable::getContentsSize() const {
size_t Size = 0;
for (auto Entry : Contents) {
switch (Entry.Length) {
case ULEB:
Size += getULEB128Size(Entry.Value);
break;
case SLEB:
Size += getSLEB128Size(Entry.Value);
break;
default:
Size += Entry.Length;
break;
}
}
return Size;
}
MCSymbol *dwarfgen::LineTable::writeDefaultPrologue(AsmPrinter &Asm) const {
MCSymbol *UnitStart = Asm.createTempSymbol("line_unit_start");
MCSymbol *UnitEnd = Asm.createTempSymbol("line_unit_end");
if (Format == DwarfFormat::DWARF64) {
Asm.emitInt32((int)dwarf::DW_LENGTH_DWARF64);
Asm.emitLabelDifference(UnitEnd, UnitStart, 8);
} else {
Asm.emitLabelDifference(UnitEnd, UnitStart, 4);
}
Asm.OutStreamer->emitLabel(UnitStart);
Asm.emitInt16(Version);
if (Version == 5) {
Asm.emitInt8(AddrSize);
Asm.emitInt8(SegSize);
}
MCSymbol *PrologueStart = Asm.createTempSymbol("line_prologue_start");
MCSymbol *PrologueEnd = Asm.createTempSymbol("line_prologue_end");
Asm.emitLabelDifference(PrologueEnd, PrologueStart,
Format == DwarfFormat::DWARF64 ? 8 : 4);
Asm.OutStreamer->emitLabel(PrologueStart);
DWARFDebugLine::Prologue DefaultPrologue = createBasicPrologue();
writeProloguePayload(DefaultPrologue, Asm);
Asm.OutStreamer->emitLabel(PrologueEnd);
return UnitEnd;
}
void dwarfgen::LineTable::writePrologue(AsmPrinter &Asm) const {
if (Format == DwarfFormat::DWARF64) {
Asm.emitInt32((int)dwarf::DW_LENGTH_DWARF64);
Asm.emitInt64(Prologue->TotalLength);
} else {
Asm.emitInt32(Prologue->TotalLength);
}
Asm.emitInt16(Prologue->getVersion());
if (Version == 5) {
Asm.emitInt8(Prologue->getAddressSize());
Asm.emitInt8(Prologue->SegSelectorSize);
}
if (Format == DwarfFormat::DWARF64)
Asm.emitInt64(Prologue->PrologueLength);
else
Asm.emitInt32(Prologue->PrologueLength);
writeProloguePayload(*Prologue, Asm);
}
static void writeCString(StringRef Str, AsmPrinter &Asm) {
Asm.OutStreamer->emitBytes(Str);
Asm.emitInt8(0);
}
static void writeV2IncludeAndFileTable(const DWARFDebugLine::Prologue &Prologue,
AsmPrinter &Asm) {
for (auto Include : Prologue.IncludeDirectories) {
assert(Include.getAsCString() && "expected a string form for include dir");
writeCString(*Include.getAsCString(), Asm);
}
Asm.emitInt8(0);
for (auto File : Prologue.FileNames) {
assert(File.Name.getAsCString() && "expected a string form for file name");
writeCString(*File.Name.getAsCString(), Asm);
Asm.emitULEB128(File.DirIdx);
Asm.emitULEB128(File.ModTime);
Asm.emitULEB128(File.Length);
}
Asm.emitInt8(0);
}
static void writeV5IncludeAndFileTable(const DWARFDebugLine::Prologue &Prologue,
AsmPrinter &Asm) {
Asm.emitInt8(1); // directory_entry_format_count.
// TODO: Add support for other content descriptions - we currently only
// support a single DW_LNCT_path/DW_FORM_string.
Asm.emitULEB128(DW_LNCT_path);
Asm.emitULEB128(DW_FORM_string);
Asm.emitULEB128(Prologue.IncludeDirectories.size());
for (auto Include : Prologue.IncludeDirectories) {
assert(Include.getAsCString() && "expected a string form for include dir");
writeCString(*Include.getAsCString(), Asm);
}
Asm.emitInt8(2); // file_name_entry_format_count.
Asm.emitULEB128(DW_LNCT_path);
Asm.emitULEB128(DW_FORM_string);
Asm.emitULEB128(DW_LNCT_directory_index);
Asm.emitULEB128(DW_FORM_data1);
Asm.emitULEB128(Prologue.FileNames.size());
for (auto File : Prologue.FileNames) {
assert(File.Name.getAsCString() && "expected a string form for file name");
writeCString(*File.Name.getAsCString(), Asm);
Asm.emitInt8(File.DirIdx);
}
}
void dwarfgen::LineTable::writeProloguePayload(
const DWARFDebugLine::Prologue &Prologue, AsmPrinter &Asm) const {
Asm.emitInt8(Prologue.MinInstLength);
if (Version >= 4)
Asm.emitInt8(Prologue.MaxOpsPerInst);
Asm.emitInt8(Prologue.DefaultIsStmt);
Asm.emitInt8(Prologue.LineBase);
Asm.emitInt8(Prologue.LineRange);
Asm.emitInt8(Prologue.OpcodeBase);
for (auto Length : Prologue.StandardOpcodeLengths) {
Asm.emitInt8(Length);
}
if (Version < 5)
writeV2IncludeAndFileTable(Prologue, Asm);
else
writeV5IncludeAndFileTable(Prologue, Asm);
}
//===----------------------------------------------------------------------===//
/// dwarfgen::Generator implementation.
//===----------------------------------------------------------------------===//
dwarfgen::Generator::Generator()
: MAB(nullptr), MCE(nullptr), MS(nullptr), TLOF(nullptr),
StringPool(nullptr), Abbreviations(Allocator),
StringOffsetsStartSym(nullptr), Version(0) {}
dwarfgen::Generator::~Generator() = default;
llvm::Expected<std::unique_ptr<dwarfgen::Generator>>
dwarfgen::Generator::create(Triple TheTriple, uint16_t DwarfVersion) {
std::unique_ptr<dwarfgen::Generator> GenUP(new dwarfgen::Generator());
llvm::Error error = GenUP->init(TheTriple, DwarfVersion);
if (error)
return Expected<std::unique_ptr<dwarfgen::Generator>>(std::move(error));
return Expected<std::unique_ptr<dwarfgen::Generator>>(std::move(GenUP));
}
llvm::Error dwarfgen::Generator::init(Triple TheTriple, uint16_t V) {
Version = V;
std::string ErrorStr;
std::string TripleName;
// Get the target.
const Target *TheTarget =
TargetRegistry::lookupTarget(TripleName, TheTriple, ErrorStr);
if (!TheTarget)
return make_error<StringError>(ErrorStr, inconvertibleErrorCode());
TripleName = TheTriple.getTriple();
// Create all the MC Objects.
MRI.reset(TheTarget->createMCRegInfo(TripleName));
if (!MRI)
return make_error<StringError>(Twine("no register info for target ") +
TripleName,
inconvertibleErrorCode());
MCTargetOptions MCOptions = mc::InitMCTargetOptionsFromFlags();
MAI.reset(TheTarget->createMCAsmInfo(*MRI, TripleName, MCOptions));
if (!MAI)
return make_error<StringError>("no asm info for target " + TripleName,
inconvertibleErrorCode());
MSTI.reset(TheTarget->createMCSubtargetInfo(TripleName, "", ""));
if (!MSTI)
return make_error<StringError>("no subtarget info for target " + TripleName,
inconvertibleErrorCode());
MAB = TheTarget->createMCAsmBackend(*MSTI, *MRI, MCOptions);
if (!MAB)
return make_error<StringError>("no asm backend for target " + TripleName,
inconvertibleErrorCode());
MII.reset(TheTarget->createMCInstrInfo());
if (!MII)
return make_error<StringError>("no instr info info for target " +
TripleName,
inconvertibleErrorCode());
TM.reset(TheTarget->createTargetMachine(TripleName, "", "", TargetOptions(),
None));
if (!TM)
return make_error<StringError>("no target machine for target " + TripleName,
inconvertibleErrorCode());
TLOF = TM->getObjFileLowering();
MC.reset(new MCContext(MAI.get(), MRI.get(), TLOF));
TLOF->Initialize(*MC, *TM);
MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, *MC);
if (!MCE)
return make_error<StringError>("no code emitter for target " + TripleName,
inconvertibleErrorCode());
Stream = std::make_unique<raw_svector_ostream>(FileBytes);
MS = TheTarget->createMCObjectStreamer(
TheTriple, *MC, std::unique_ptr<MCAsmBackend>(MAB),
MAB->createObjectWriter(*Stream), std::unique_ptr<MCCodeEmitter>(MCE),
*MSTI, MCOptions.MCRelaxAll, MCOptions.MCIncrementalLinkerCompatible,
/*DWARFMustBeAtTheEnd*/ false);
if (!MS)
return make_error<StringError>("no object streamer for target " +
TripleName,
inconvertibleErrorCode());
// Finally create the AsmPrinter we'll use to emit the DIEs.
Asm.reset(TheTarget->createAsmPrinter(*TM, std::unique_ptr<MCStreamer>(MS)));
if (!Asm)
return make_error<StringError>("no asm printer for target " + TripleName,
inconvertibleErrorCode());
// Set the DWARF version correctly on all classes that we use.
MC->setDwarfVersion(Version);
Asm->setDwarfVersion(Version);
StringPool = std::make_unique<DwarfStringPool>(Allocator, *Asm, StringRef());
StringOffsetsStartSym = Asm->createTempSymbol("str_offsets_base");
return Error::success();
}
StringRef dwarfgen::Generator::generate() {
// Offset from the first CU in the debug info section is 0 initially.
uint64_t SecOffset = 0;
// Iterate over each compile unit and set the size and offsets for each
// DIE within each compile unit. All offsets are CU relative.
for (auto &CU : CompileUnits) {
// Set the absolute .debug_info offset for this compile unit.
CU->setOffset(SecOffset);
// The DIEs contain compile unit relative offsets.
unsigned CUOffset = 11;
CUOffset = CU->getUnitDIE().computeSizeAndOffsets(CUOffset);
// Update our absolute .debug_info offset.
SecOffset += CUOffset;
CU->setLength(CUOffset - 4);
}
Abbreviations.Emit(Asm.get(), TLOF->getDwarfAbbrevSection());
StringPool->emitStringOffsetsTableHeader(*Asm, TLOF->getDwarfStrOffSection(),
StringOffsetsStartSym);
StringPool->emit(*Asm, TLOF->getDwarfStrSection(),
TLOF->getDwarfStrOffSection());
MS->SwitchSection(TLOF->getDwarfInfoSection());
for (auto &CU : CompileUnits) {
uint16_t Version = CU->getVersion();
auto Length = CU->getLength();
MC->setDwarfVersion(Version);
assert(Length != -1U);
Asm->emitInt32(Length);
Asm->emitInt16(Version);
if (Version <= 4) {
Asm->emitInt32(0);
Asm->emitInt8(CU->getAddressSize());
} else {
Asm->emitInt8(dwarf::DW_UT_compile);
Asm->emitInt8(CU->getAddressSize());
Asm->emitInt32(0);
}
Asm->emitDwarfDIE(*CU->getUnitDIE().Die);
}
MS->SwitchSection(TLOF->getDwarfLineSection());
for (auto &LT : LineTables)
LT->generate(*MC, *Asm);
MS->Finish();
if (FileBytes.empty())
return StringRef();
return StringRef(FileBytes.data(), FileBytes.size());
}
bool dwarfgen::Generator::saveFile(StringRef Path) {
if (FileBytes.empty())
return false;
std::error_code EC;
raw_fd_ostream Strm(Path, EC, sys::fs::OF_None);
if (EC)
return false;
Strm.write(FileBytes.data(), FileBytes.size());
Strm.close();
return true;
}
dwarfgen::CompileUnit &dwarfgen::Generator::addCompileUnit() {
CompileUnits.push_back(
std::make_unique<CompileUnit>(*this, Version, Asm->getPointerSize()));
return *CompileUnits.back();
}
dwarfgen::LineTable &dwarfgen::Generator::addLineTable(DwarfFormat Format) {
LineTables.push_back(
std::make_unique<LineTable>(Version, Format, Asm->getPointerSize()));
return *LineTables.back();
}
Reference in New Issue View Git Blame Copy Permalink