llvm-6502/lib/DebugInfo/DWARFDebugFrame.cpp
Chandler Carruth 974a445bd9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 11:48:04 +00:00

392 lines
13 KiB
C++

//===-- 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/ErrorHandling.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"
#include <string>
#include <vector>
using namespace llvm;
using namespace dwarf;
/// \brief Abstract frame entry defining the common interface concrete
/// entries implement.
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) {}
virtual ~FrameEntry() {
}
FrameKind getKind() const { return Kind; }
virtual uint64_t getOffset() const { return Offset; }
/// \brief Parse and store a sequence of CFI instructions from our data
/// stream, starting at *Offset and ending at EndOffset. If everything
/// goes well, *Offset should be equal to EndOffset when this method
/// returns. Otherwise, an error occurred.
virtual void parseInstructions(uint32_t *Offset, uint32_t EndOffset);
/// \brief Dump the entry header to the given output stream.
virtual void dumpHeader(raw_ostream &OS) const = 0;
/// \brief Dump the entry's instructions to the given output stream.
virtual void dumpInstructions(raw_ostream &OS) const;
protected:
const FrameKind Kind;
/// \brief The data stream holding the section from which the entry was
/// parsed.
DataExtractor Data;
/// \brief Offset of this entry in the section.
uint64_t Offset;
/// \brief Entry length as specified in DWARF.
uint64_t Length;
/// An entry may contain CFI instructions. An instruction consists of an
/// opcode and an optional sequence of operands.
typedef std::vector<uint64_t> Operands;
struct Instruction {
Instruction(uint8_t Opcode)
: Opcode(Opcode)
{}
uint8_t Opcode;
Operands Ops;
};
std::vector<Instruction> Instructions;
/// Convenience methods to add a new instruction with the given opcode and
/// operands to the Instructions vector.
void addInstruction(uint8_t Opcode) {
Instructions.push_back(Instruction(Opcode));
}
void addInstruction(uint8_t Opcode, uint64_t Operand1) {
Instructions.push_back(Instruction(Opcode));
Instructions.back().Ops.push_back(Operand1);
}
void addInstruction(uint8_t Opcode, uint64_t Operand1, uint64_t Operand2) {
Instructions.push_back(Instruction(Opcode));
Instructions.back().Ops.push_back(Operand1);
Instructions.back().Ops.push_back(Operand2);
}
};
// See DWARF standard v3, section 7.23
const uint8_t DWARF_CFI_PRIMARY_OPCODE_MASK = 0xc0;
const uint8_t DWARF_CFI_PRIMARY_OPERAND_MASK = 0x3f;
void FrameEntry::parseInstructions(uint32_t *Offset, uint32_t EndOffset) {
while (*Offset < EndOffset) {
uint8_t Opcode = Data.getU8(Offset);
// Some instructions have a primary opcode encoded in the top bits.
uint8_t Primary = Opcode & DWARF_CFI_PRIMARY_OPCODE_MASK;
if (Primary) {
// If it's a primary opcode, the first operand is encoded in the bottom
// bits of the opcode itself.
uint64_t Op1 = Opcode & DWARF_CFI_PRIMARY_OPERAND_MASK;
switch (Primary) {
default: llvm_unreachable("Impossible primary CFI opcode");
case DW_CFA_advance_loc:
case DW_CFA_restore:
addInstruction(Primary, Op1);
break;
case DW_CFA_offset:
addInstruction(Primary, Op1, Data.getULEB128(Offset));
break;
}
} else {
// Extended opcode - its value is Opcode itself.
switch (Opcode) {
default: llvm_unreachable("Invalid extended CFI opcode");
case DW_CFA_nop:
case DW_CFA_remember_state:
case DW_CFA_restore_state:
// No operands
addInstruction(Opcode);
break;
case DW_CFA_set_loc:
// Operands: Address
addInstruction(Opcode, Data.getAddress(Offset));
break;
case DW_CFA_advance_loc1:
// Operands: 1-byte delta
addInstruction(Opcode, Data.getU8(Offset));
break;
case DW_CFA_advance_loc2:
// Operands: 2-byte delta
addInstruction(Opcode, Data.getU16(Offset));
break;
case DW_CFA_advance_loc4:
// Operands: 4-byte delta
addInstruction(Opcode, Data.getU32(Offset));
break;
case DW_CFA_restore_extended:
case DW_CFA_undefined:
case DW_CFA_same_value:
case DW_CFA_def_cfa_register:
case DW_CFA_def_cfa_offset:
// Operands: ULEB128
addInstruction(Opcode, Data.getULEB128(Offset));
break;
case DW_CFA_def_cfa_offset_sf:
// Operands: SLEB128
addInstruction(Opcode, Data.getSLEB128(Offset));
break;
case DW_CFA_offset_extended:
case DW_CFA_register:
case DW_CFA_def_cfa:
case DW_CFA_val_offset:
// Operands: ULEB128, ULEB128
addInstruction(Opcode, Data.getULEB128(Offset),
Data.getULEB128(Offset));
break;
case DW_CFA_offset_extended_sf:
case DW_CFA_def_cfa_sf:
case DW_CFA_val_offset_sf:
// Operands: ULEB128, SLEB128
addInstruction(Opcode, Data.getULEB128(Offset),
Data.getSLEB128(Offset));
break;
case DW_CFA_def_cfa_expression:
case DW_CFA_expression:
case DW_CFA_val_expression:
// TODO: implement this
report_fatal_error("Values with expressions not implemented yet!");
}
}
}
}
void FrameEntry::dumpInstructions(raw_ostream &OS) const {
// TODO: at the moment only instruction names are dumped. Expand this to
// dump operands as well.
for (std::vector<Instruction>::const_iterator I = Instructions.begin(),
E = Instructions.end();
I != E; ++I) {
uint8_t Opcode = I->Opcode;
if (Opcode & DWARF_CFI_PRIMARY_OPCODE_MASK)
Opcode &= DWARF_CFI_PRIMARY_OPCODE_MASK;
OS << " " << CallFrameString(Opcode) << ":\n";
}
}
namespace {
/// \brief DWARF Common Information Entry (CIE)
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) {}
~CIE() {
}
void dumpHeader(raw_ostream &OS) const {
OS << format("%08x %08x %08x CIE",
(uint32_t)Offset, (uint32_t)Length, DW_CIE_ID)
<< "\n";
OS << format(" Version: %d\n", Version);
OS << " Augmentation: \"" << Augmentation << "\"\n";
OS << format(" Code alignment factor: %u\n",
(uint32_t)CodeAlignmentFactor);
OS << format(" Data alignment factor: %d\n",
(int32_t)DataAlignmentFactor);
OS << format(" Return address column: %d\n",
(int32_t)ReturnAddressRegister);
OS << "\n";
}
static bool classof(const FrameEntry *FE) {
return FE->getKind() == FK_CIE;
}
private:
/// The following fields are defined in section 6.4.1 of the DWARF standard v3
uint8_t Version;
SmallString<8> Augmentation;
uint64_t CodeAlignmentFactor;
int64_t DataAlignmentFactor;
uint64_t ReturnAddressRegister;
};
/// \brief DWARF Frame Description Entry (FDE)
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) {}
~FDE() {
}
void dumpHeader(raw_ostream &OS) const {
OS << format("%08x %08x %08x FDE ",
(uint32_t)Offset, (uint32_t)Length, (int32_t)LinkedCIEOffset);
OS << format("cie=%08x pc=%08x...%08x\n",
(int32_t)LinkedCIEOffset,
(uint32_t)InitialLocation,
(uint32_t)InitialLocation + (uint32_t)AddressRange);
if (LinkedCIE) {
OS << format("%p\n", LinkedCIE);
}
}
static bool classof(const FrameEntry *FE) {
return FE->getKind() == FK_FDE;
}
private:
/// The following fields are defined in section 6.4.1 of the DWARF standard v3
uint64_t LinkedCIEOffset;
uint64_t InitialLocation;
uint64_t AddressRange;
CIE *LinkedCIE;
};
} // end anonymous namespace
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<uint32_t>(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);
FrameEntry *Entry = 0;
if (IsCIE) {
// Note: this is specifically DWARFv3 CIE header structure. It was
// changed in DWARFv4. We currently don't support reading DWARFv4
// here because LLVM itself does not emit it (and LLDB doesn't
// support it either).
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);
Entry = new CIE(Data, StartOffset, Length, Version,
StringRef(Augmentation), CodeAlignmentFactor,
DataAlignmentFactor, ReturnAddressRegister);
} else {
// FDE
uint64_t CIEPointer = Id;
uint64_t InitialLocation = Data.getAddress(&Offset);
uint64_t AddressRange = Data.getAddress(&Offset);
Entry = new FDE(Data, StartOffset, Length, CIEPointer,
InitialLocation, AddressRange);
}
assert(Entry && "Expected Entry to be populated with CIE or FDE");
Entry->parseInstructions(&Offset, EndStructureOffset);
if (Offset == EndStructureOffset) {
// Entry instrucitons parsed successfully.
Entries.push_back(Entry);
} else {
std::string Str;
raw_string_ostream OS(Str);
OS << format("Parsing entry instructions at %lx failed",
Entry->getOffset());
report_fatal_error(Str);
}
}
}
void DWARFDebugFrame::dump(raw_ostream &OS) const {
OS << "\n";
for (EntryVector::const_iterator I = Entries.begin(), E = Entries.end();
I != E; ++I) {
FrameEntry *Entry = *I;
Entry->dumpHeader(OS);
Entry->dumpInstructions(OS);
OS << "\n";
}
}