forked from OSchip/llvm-project
676 lines
23 KiB
C++
676 lines
23 KiB
C++
//===-- DWARFDebugFrame.h - Parsing of .debug_frame -------------*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/Optional.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/Support/Casting.h"
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#include "llvm/Support/DataTypes.h"
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#include "llvm/Support/Dwarf.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/Format.h"
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#include "llvm/Support/raw_ostream.h"
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#include <string>
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#include <vector>
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using namespace llvm;
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using namespace dwarf;
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/// \brief Abstract frame entry defining the common interface concrete
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/// entries implement.
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class llvm::FrameEntry {
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public:
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enum FrameKind {FK_CIE, FK_FDE};
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FrameEntry(FrameKind K, uint64_t Offset, uint64_t Length)
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: Kind(K), Offset(Offset), Length(Length) {}
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virtual ~FrameEntry() {
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}
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FrameKind getKind() const { return Kind; }
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virtual uint64_t getOffset() const { return Offset; }
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/// \brief Parse and store a sequence of CFI instructions from Data,
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/// starting at *Offset and ending at EndOffset. If everything
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/// goes well, *Offset should be equal to EndOffset when this method
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/// returns. Otherwise, an error occurred.
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virtual void parseInstructions(DataExtractor Data, uint32_t *Offset,
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uint32_t EndOffset);
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/// \brief Dump the entry header to the given output stream.
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virtual void dumpHeader(raw_ostream &OS) const = 0;
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/// \brief Dump the entry's instructions to the given output stream.
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virtual void dumpInstructions(raw_ostream &OS) const;
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protected:
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const FrameKind Kind;
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/// \brief Offset of this entry in the section.
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uint64_t Offset;
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/// \brief Entry length as specified in DWARF.
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uint64_t Length;
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/// An entry may contain CFI instructions. An instruction consists of an
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/// opcode and an optional sequence of operands.
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typedef std::vector<uint64_t> Operands;
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struct Instruction {
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Instruction(uint8_t Opcode)
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: Opcode(Opcode)
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{}
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uint8_t Opcode;
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Operands Ops;
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};
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std::vector<Instruction> Instructions;
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/// Convenience methods to add a new instruction with the given opcode and
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/// operands to the Instructions vector.
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void addInstruction(uint8_t Opcode) {
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Instructions.push_back(Instruction(Opcode));
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}
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void addInstruction(uint8_t Opcode, uint64_t Operand1) {
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Instructions.push_back(Instruction(Opcode));
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Instructions.back().Ops.push_back(Operand1);
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}
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void addInstruction(uint8_t Opcode, uint64_t Operand1, uint64_t Operand2) {
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Instructions.push_back(Instruction(Opcode));
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Instructions.back().Ops.push_back(Operand1);
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Instructions.back().Ops.push_back(Operand2);
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}
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};
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// See DWARF standard v3, section 7.23
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const uint8_t DWARF_CFI_PRIMARY_OPCODE_MASK = 0xc0;
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const uint8_t DWARF_CFI_PRIMARY_OPERAND_MASK = 0x3f;
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void FrameEntry::parseInstructions(DataExtractor Data, uint32_t *Offset,
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uint32_t EndOffset) {
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while (*Offset < EndOffset) {
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uint8_t Opcode = Data.getU8(Offset);
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// Some instructions have a primary opcode encoded in the top bits.
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uint8_t Primary = Opcode & DWARF_CFI_PRIMARY_OPCODE_MASK;
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if (Primary) {
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// If it's a primary opcode, the first operand is encoded in the bottom
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// bits of the opcode itself.
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uint64_t Op1 = Opcode & DWARF_CFI_PRIMARY_OPERAND_MASK;
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switch (Primary) {
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default: llvm_unreachable("Impossible primary CFI opcode");
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case DW_CFA_advance_loc:
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case DW_CFA_restore:
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addInstruction(Primary, Op1);
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break;
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case DW_CFA_offset:
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addInstruction(Primary, Op1, Data.getULEB128(Offset));
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break;
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}
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} else {
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// Extended opcode - its value is Opcode itself.
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switch (Opcode) {
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default: llvm_unreachable("Invalid extended CFI opcode");
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case DW_CFA_nop:
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case DW_CFA_remember_state:
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case DW_CFA_restore_state:
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case DW_CFA_GNU_window_save:
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// No operands
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addInstruction(Opcode);
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break;
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case DW_CFA_set_loc:
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// Operands: Address
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addInstruction(Opcode, Data.getAddress(Offset));
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break;
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case DW_CFA_advance_loc1:
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// Operands: 1-byte delta
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addInstruction(Opcode, Data.getU8(Offset));
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break;
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case DW_CFA_advance_loc2:
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// Operands: 2-byte delta
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addInstruction(Opcode, Data.getU16(Offset));
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break;
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case DW_CFA_advance_loc4:
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// Operands: 4-byte delta
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addInstruction(Opcode, Data.getU32(Offset));
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break;
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case DW_CFA_restore_extended:
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case DW_CFA_undefined:
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case DW_CFA_same_value:
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case DW_CFA_def_cfa_register:
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case DW_CFA_def_cfa_offset:
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// Operands: ULEB128
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addInstruction(Opcode, Data.getULEB128(Offset));
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break;
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case DW_CFA_def_cfa_offset_sf:
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// Operands: SLEB128
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addInstruction(Opcode, Data.getSLEB128(Offset));
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break;
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case DW_CFA_offset_extended:
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case DW_CFA_register:
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case DW_CFA_def_cfa:
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case DW_CFA_val_offset: {
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// Operands: ULEB128, ULEB128
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// Note: We can not embed getULEB128 directly into function
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// argument list. getULEB128 changes Offset and order of evaluation
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// for arguments is unspecified.
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auto op1 = Data.getULEB128(Offset);
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auto op2 = Data.getULEB128(Offset);
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addInstruction(Opcode, op1, op2);
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break;
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}
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case DW_CFA_offset_extended_sf:
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case DW_CFA_def_cfa_sf:
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case DW_CFA_val_offset_sf: {
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// Operands: ULEB128, SLEB128
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// Note: see comment for the previous case
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auto op1 = Data.getULEB128(Offset);
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auto op2 = (uint64_t)Data.getSLEB128(Offset);
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addInstruction(Opcode, op1, op2);
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break;
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}
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case DW_CFA_def_cfa_expression:
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case DW_CFA_expression:
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case DW_CFA_val_expression:
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// TODO: implement this
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report_fatal_error("Values with expressions not implemented yet!");
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}
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}
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}
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}
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namespace {
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/// \brief DWARF Common Information Entry (CIE)
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class CIE : public FrameEntry {
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public:
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// CIEs (and FDEs) are simply container classes, so the only sensible way to
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// create them is by providing the full parsed contents in the constructor.
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CIE(uint64_t Offset, uint64_t Length, uint8_t Version,
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SmallString<8> Augmentation, uint8_t AddressSize,
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uint8_t SegmentDescriptorSize, uint64_t CodeAlignmentFactor,
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int64_t DataAlignmentFactor, uint64_t ReturnAddressRegister,
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SmallString<8> AugmentationData, uint32_t FDEPointerEncoding,
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uint32_t LSDAPointerEncoding)
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: FrameEntry(FK_CIE, Offset, Length), Version(Version),
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Augmentation(std::move(Augmentation)),
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AddressSize(AddressSize),
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SegmentDescriptorSize(SegmentDescriptorSize),
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CodeAlignmentFactor(CodeAlignmentFactor),
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DataAlignmentFactor(DataAlignmentFactor),
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ReturnAddressRegister(ReturnAddressRegister),
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AugmentationData(AugmentationData),
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FDEPointerEncoding(FDEPointerEncoding),
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LSDAPointerEncoding(LSDAPointerEncoding) { }
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~CIE() override {}
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StringRef getAugmentationString() const { return Augmentation; }
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uint64_t getCodeAlignmentFactor() const { return CodeAlignmentFactor; }
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int64_t getDataAlignmentFactor() const { return DataAlignmentFactor; }
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uint32_t getFDEPointerEncoding() const {
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return FDEPointerEncoding;
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}
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uint32_t getLSDAPointerEncoding() const {
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return LSDAPointerEncoding;
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}
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void dumpHeader(raw_ostream &OS) const override {
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OS << format("%08x %08x %08x CIE",
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(uint32_t)Offset, (uint32_t)Length, DW_CIE_ID)
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<< "\n";
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OS << format(" Version: %d\n", Version);
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OS << " Augmentation: \"" << Augmentation << "\"\n";
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if (Version >= 4) {
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OS << format(" Address size: %u\n",
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(uint32_t)AddressSize);
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OS << format(" Segment desc size: %u\n",
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(uint32_t)SegmentDescriptorSize);
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}
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OS << format(" Code alignment factor: %u\n",
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(uint32_t)CodeAlignmentFactor);
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OS << format(" Data alignment factor: %d\n",
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(int32_t)DataAlignmentFactor);
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OS << format(" Return address column: %d\n",
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(int32_t)ReturnAddressRegister);
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if (!AugmentationData.empty())
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OS << " Augmentation data: " << AugmentationData << "\n";
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OS << "\n";
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}
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static bool classof(const FrameEntry *FE) {
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return FE->getKind() == FK_CIE;
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}
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private:
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/// The following fields are defined in section 6.4.1 of the DWARF standard v4
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uint8_t Version;
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SmallString<8> Augmentation;
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uint8_t AddressSize;
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uint8_t SegmentDescriptorSize;
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uint64_t CodeAlignmentFactor;
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int64_t DataAlignmentFactor;
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uint64_t ReturnAddressRegister;
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// The following are used when the CIE represents an EH frame entry.
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SmallString<8> AugmentationData;
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uint32_t FDEPointerEncoding;
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uint32_t LSDAPointerEncoding;
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};
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/// \brief DWARF Frame Description Entry (FDE)
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class FDE : public FrameEntry {
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public:
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// Each FDE has a CIE it's "linked to". Our FDE contains is constructed with
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// an offset to the CIE (provided by parsing the FDE header). The CIE itself
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// is obtained lazily once it's actually required.
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FDE(uint64_t Offset, uint64_t Length, int64_t LinkedCIEOffset,
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uint64_t InitialLocation, uint64_t AddressRange,
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CIE *Cie)
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: FrameEntry(FK_FDE, Offset, Length), LinkedCIEOffset(LinkedCIEOffset),
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InitialLocation(InitialLocation), AddressRange(AddressRange),
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LinkedCIE(Cie) {}
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~FDE() override {}
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CIE *getLinkedCIE() const { return LinkedCIE; }
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void dumpHeader(raw_ostream &OS) const override {
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OS << format("%08x %08x %08x FDE ",
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(uint32_t)Offset, (uint32_t)Length, (int32_t)LinkedCIEOffset);
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OS << format("cie=%08x pc=%08x...%08x\n",
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(int32_t)LinkedCIEOffset,
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(uint32_t)InitialLocation,
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(uint32_t)InitialLocation + (uint32_t)AddressRange);
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}
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static bool classof(const FrameEntry *FE) {
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return FE->getKind() == FK_FDE;
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}
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private:
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/// The following fields are defined in section 6.4.1 of the DWARF standard v3
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uint64_t LinkedCIEOffset;
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uint64_t InitialLocation;
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uint64_t AddressRange;
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CIE *LinkedCIE;
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};
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/// \brief Types of operands to CF instructions.
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enum OperandType {
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OT_Unset,
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OT_None,
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OT_Address,
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OT_Offset,
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OT_FactoredCodeOffset,
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OT_SignedFactDataOffset,
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OT_UnsignedFactDataOffset,
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OT_Register,
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OT_Expression
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};
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} // end anonymous namespace
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/// \brief Initialize the array describing the types of operands.
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static ArrayRef<OperandType[2]> getOperandTypes() {
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static OperandType OpTypes[DW_CFA_restore+1][2];
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#define DECLARE_OP2(OP, OPTYPE0, OPTYPE1) \
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do { \
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OpTypes[OP][0] = OPTYPE0; \
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OpTypes[OP][1] = OPTYPE1; \
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} while (0)
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#define DECLARE_OP1(OP, OPTYPE0) DECLARE_OP2(OP, OPTYPE0, OT_None)
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#define DECLARE_OP0(OP) DECLARE_OP1(OP, OT_None)
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DECLARE_OP1(DW_CFA_set_loc, OT_Address);
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DECLARE_OP1(DW_CFA_advance_loc, OT_FactoredCodeOffset);
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DECLARE_OP1(DW_CFA_advance_loc1, OT_FactoredCodeOffset);
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DECLARE_OP1(DW_CFA_advance_loc2, OT_FactoredCodeOffset);
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DECLARE_OP1(DW_CFA_advance_loc4, OT_FactoredCodeOffset);
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DECLARE_OP1(DW_CFA_MIPS_advance_loc8, OT_FactoredCodeOffset);
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DECLARE_OP2(DW_CFA_def_cfa, OT_Register, OT_Offset);
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DECLARE_OP2(DW_CFA_def_cfa_sf, OT_Register, OT_SignedFactDataOffset);
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DECLARE_OP1(DW_CFA_def_cfa_register, OT_Register);
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DECLARE_OP1(DW_CFA_def_cfa_offset, OT_Offset);
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DECLARE_OP1(DW_CFA_def_cfa_offset_sf, OT_SignedFactDataOffset);
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DECLARE_OP1(DW_CFA_def_cfa_expression, OT_Expression);
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DECLARE_OP1(DW_CFA_undefined, OT_Register);
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DECLARE_OP1(DW_CFA_same_value, OT_Register);
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DECLARE_OP2(DW_CFA_offset, OT_Register, OT_UnsignedFactDataOffset);
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DECLARE_OP2(DW_CFA_offset_extended, OT_Register, OT_UnsignedFactDataOffset);
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DECLARE_OP2(DW_CFA_offset_extended_sf, OT_Register, OT_SignedFactDataOffset);
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DECLARE_OP2(DW_CFA_val_offset, OT_Register, OT_UnsignedFactDataOffset);
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DECLARE_OP2(DW_CFA_val_offset_sf, OT_Register, OT_SignedFactDataOffset);
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DECLARE_OP2(DW_CFA_register, OT_Register, OT_Register);
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DECLARE_OP2(DW_CFA_expression, OT_Register, OT_Expression);
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DECLARE_OP2(DW_CFA_val_expression, OT_Register, OT_Expression);
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DECLARE_OP1(DW_CFA_restore, OT_Register);
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DECLARE_OP1(DW_CFA_restore_extended, OT_Register);
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DECLARE_OP0(DW_CFA_remember_state);
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DECLARE_OP0(DW_CFA_restore_state);
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DECLARE_OP0(DW_CFA_GNU_window_save);
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DECLARE_OP1(DW_CFA_GNU_args_size, OT_Offset);
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DECLARE_OP0(DW_CFA_nop);
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#undef DECLARE_OP0
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#undef DECLARE_OP1
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#undef DECLARE_OP2
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return ArrayRef<OperandType[2]>(&OpTypes[0], DW_CFA_restore+1);
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}
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static ArrayRef<OperandType[2]> OpTypes = getOperandTypes();
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/// \brief Print \p Opcode's operand number \p OperandIdx which has
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/// value \p Operand.
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static void printOperand(raw_ostream &OS, uint8_t Opcode, unsigned OperandIdx,
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uint64_t Operand, uint64_t CodeAlignmentFactor,
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int64_t DataAlignmentFactor) {
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assert(OperandIdx < 2);
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OperandType Type = OpTypes[Opcode][OperandIdx];
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switch (Type) {
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case OT_Unset:
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OS << " Unsupported " << (OperandIdx ? "second" : "first") << " operand to";
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if (const char *OpcodeName = CallFrameString(Opcode))
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OS << " " << OpcodeName;
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else
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OS << format(" Opcode %x", Opcode);
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break;
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case OT_None:
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break;
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case OT_Address:
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OS << format(" %" PRIx64, Operand);
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break;
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case OT_Offset:
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// The offsets are all encoded in a unsigned form, but in practice
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// consumers use them signed. It's most certainly legacy due to
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// the lack of signed variants in the first Dwarf standards.
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OS << format(" %+" PRId64, int64_t(Operand));
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break;
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case OT_FactoredCodeOffset: // Always Unsigned
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if (CodeAlignmentFactor)
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OS << format(" %" PRId64, Operand * CodeAlignmentFactor);
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else
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OS << format(" %" PRId64 "*code_alignment_factor" , Operand);
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break;
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case OT_SignedFactDataOffset:
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if (DataAlignmentFactor)
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OS << format(" %" PRId64, int64_t(Operand) * DataAlignmentFactor);
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else
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OS << format(" %" PRId64 "*data_alignment_factor" , int64_t(Operand));
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break;
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case OT_UnsignedFactDataOffset:
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if (DataAlignmentFactor)
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OS << format(" %" PRId64, Operand * DataAlignmentFactor);
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else
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OS << format(" %" PRId64 "*data_alignment_factor" , Operand);
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break;
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case OT_Register:
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OS << format(" reg%" PRId64, Operand);
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break;
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case OT_Expression:
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OS << " expression";
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break;
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}
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}
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void FrameEntry::dumpInstructions(raw_ostream &OS) const {
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uint64_t CodeAlignmentFactor = 0;
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int64_t DataAlignmentFactor = 0;
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const CIE *Cie = dyn_cast<CIE>(this);
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if (!Cie)
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Cie = cast<FDE>(this)->getLinkedCIE();
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if (Cie) {
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CodeAlignmentFactor = Cie->getCodeAlignmentFactor();
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DataAlignmentFactor = Cie->getDataAlignmentFactor();
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}
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for (const auto &Instr : Instructions) {
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uint8_t Opcode = Instr.Opcode;
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if (Opcode & DWARF_CFI_PRIMARY_OPCODE_MASK)
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Opcode &= DWARF_CFI_PRIMARY_OPCODE_MASK;
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OS << " " << CallFrameString(Opcode) << ":";
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for (unsigned i = 0; i < Instr.Ops.size(); ++i)
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printOperand(OS, Opcode, i, Instr.Ops[i], CodeAlignmentFactor,
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DataAlignmentFactor);
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OS << '\n';
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}
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}
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DWARFDebugFrame::DWARFDebugFrame(bool IsEH) : IsEH(IsEH) {
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}
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DWARFDebugFrame::~DWARFDebugFrame() {
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}
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static void LLVM_ATTRIBUTE_UNUSED dumpDataAux(DataExtractor Data,
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uint32_t Offset, int Length) {
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errs() << "DUMP: ";
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for (int i = 0; i < Length; ++i) {
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uint8_t c = Data.getU8(&Offset);
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|
errs().write_hex(c); errs() << " ";
|
|
}
|
|
errs() << "\n";
|
|
}
|
|
|
|
static unsigned getSizeForEncoding(const DataExtractor &Data,
|
|
unsigned symbolEncoding) {
|
|
unsigned format = symbolEncoding & 0x0f;
|
|
switch (format) {
|
|
default: llvm_unreachable("Unknown Encoding");
|
|
case dwarf::DW_EH_PE_absptr:
|
|
case dwarf::DW_EH_PE_signed:
|
|
return Data.getAddressSize();
|
|
case dwarf::DW_EH_PE_udata2:
|
|
case dwarf::DW_EH_PE_sdata2:
|
|
return 2;
|
|
case dwarf::DW_EH_PE_udata4:
|
|
case dwarf::DW_EH_PE_sdata4:
|
|
return 4;
|
|
case dwarf::DW_EH_PE_udata8:
|
|
case dwarf::DW_EH_PE_sdata8:
|
|
return 8;
|
|
}
|
|
}
|
|
|
|
static uint64_t readPointer(const DataExtractor &Data, uint32_t &Offset,
|
|
unsigned Encoding) {
|
|
switch (getSizeForEncoding(Data, Encoding)) {
|
|
case 2:
|
|
return Data.getU16(&Offset);
|
|
case 4:
|
|
return Data.getU32(&Offset);
|
|
case 8:
|
|
return Data.getU64(&Offset);
|
|
default:
|
|
llvm_unreachable("Illegal data size");
|
|
}
|
|
}
|
|
|
|
void DWARFDebugFrame::parse(DataExtractor Data) {
|
|
uint32_t Offset = 0;
|
|
DenseMap<uint32_t, CIE *> CIEs;
|
|
|
|
while (Data.isValidOffset(Offset)) {
|
|
uint32_t StartOffset = Offset;
|
|
|
|
auto ReportError = [StartOffset](const char *ErrorMsg) {
|
|
std::string Str;
|
|
raw_string_ostream OS(Str);
|
|
OS << format(ErrorMsg, StartOffset);
|
|
OS.flush();
|
|
report_fatal_error(Str);
|
|
};
|
|
|
|
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 StartStructureOffset = Offset;
|
|
uint32_t EndStructureOffset = Offset + static_cast<uint32_t>(Length);
|
|
|
|
// The Id field's size depends on the DWARF format
|
|
Id = Data.getUnsigned(&Offset, (IsDWARF64 && !IsEH) ? 8 : 4);
|
|
bool IsCIE = ((IsDWARF64 && Id == DW64_CIE_ID) ||
|
|
Id == DW_CIE_ID ||
|
|
(IsEH && !Id));
|
|
|
|
if (IsCIE) {
|
|
uint8_t Version = Data.getU8(&Offset);
|
|
const char *Augmentation = Data.getCStr(&Offset);
|
|
StringRef AugmentationString(Augmentation ? Augmentation : "");
|
|
uint8_t AddressSize = Version < 4 ? Data.getAddressSize() :
|
|
Data.getU8(&Offset);
|
|
Data.setAddressSize(AddressSize);
|
|
uint8_t SegmentDescriptorSize = Version < 4 ? 0 : Data.getU8(&Offset);
|
|
uint64_t CodeAlignmentFactor = Data.getULEB128(&Offset);
|
|
int64_t DataAlignmentFactor = Data.getSLEB128(&Offset);
|
|
uint64_t ReturnAddressRegister = Data.getULEB128(&Offset);
|
|
|
|
// Parse the augmentation data for EH CIEs
|
|
StringRef AugmentationData("");
|
|
uint32_t FDEPointerEncoding = DW_EH_PE_omit;
|
|
uint32_t LSDAPointerEncoding = DW_EH_PE_omit;
|
|
if (IsEH) {
|
|
Optional<uint32_t> PersonalityEncoding;
|
|
Optional<uint64_t> Personality;
|
|
|
|
Optional<uint64_t> AugmentationLength;
|
|
uint32_t StartAugmentationOffset;
|
|
uint32_t EndAugmentationOffset;
|
|
|
|
// Walk the augmentation string to get all the augmentation data.
|
|
for (unsigned i = 0, e = AugmentationString.size(); i != e; ++i) {
|
|
switch (AugmentationString[i]) {
|
|
default:
|
|
ReportError("Unknown augmentation character in entry at %lx");
|
|
case 'L':
|
|
LSDAPointerEncoding = Data.getU8(&Offset);
|
|
break;
|
|
case 'P': {
|
|
if (Personality)
|
|
ReportError("Duplicate personality in entry at %lx");
|
|
PersonalityEncoding = Data.getU8(&Offset);
|
|
Personality = readPointer(Data, Offset, *PersonalityEncoding);
|
|
break;
|
|
}
|
|
case 'R':
|
|
FDEPointerEncoding = Data.getU8(&Offset);
|
|
break;
|
|
case 'z':
|
|
if (i)
|
|
ReportError("'z' must be the first character at %lx");
|
|
// Parse the augmentation length first. We only parse it if
|
|
// the string contains a 'z'.
|
|
AugmentationLength = Data.getULEB128(&Offset);
|
|
StartAugmentationOffset = Offset;
|
|
EndAugmentationOffset = Offset +
|
|
static_cast<uint32_t>(*AugmentationLength);
|
|
}
|
|
}
|
|
|
|
if (AugmentationLength.hasValue()) {
|
|
if (Offset != EndAugmentationOffset)
|
|
ReportError("Parsing augmentation data at %lx failed");
|
|
|
|
AugmentationData = Data.getData().slice(StartAugmentationOffset,
|
|
EndAugmentationOffset);
|
|
}
|
|
}
|
|
|
|
auto Cie = make_unique<CIE>(StartOffset, Length, Version,
|
|
AugmentationString, AddressSize,
|
|
SegmentDescriptorSize, CodeAlignmentFactor,
|
|
DataAlignmentFactor, ReturnAddressRegister,
|
|
AugmentationData, FDEPointerEncoding,
|
|
LSDAPointerEncoding);
|
|
CIEs[StartOffset] = Cie.get();
|
|
Entries.emplace_back(std::move(Cie));
|
|
} else {
|
|
// FDE
|
|
uint64_t CIEPointer = Id;
|
|
uint64_t InitialLocation = 0;
|
|
uint64_t AddressRange = 0;
|
|
CIE *Cie = CIEs[IsEH ? (StartStructureOffset - CIEPointer) : CIEPointer];
|
|
|
|
if (IsEH) {
|
|
// The address size is encoded in the CIE we reference.
|
|
if (!Cie)
|
|
ReportError("Parsing FDE data at %lx failed due to missing CIE");
|
|
|
|
InitialLocation = readPointer(Data, Offset,
|
|
Cie->getFDEPointerEncoding());
|
|
AddressRange = readPointer(Data, Offset,
|
|
Cie->getFDEPointerEncoding());
|
|
|
|
StringRef AugmentationString = Cie->getAugmentationString();
|
|
if (!AugmentationString.empty()) {
|
|
// Parse the augmentation length and data for this FDE.
|
|
uint64_t AugmentationLength = Data.getULEB128(&Offset);
|
|
|
|
uint32_t EndAugmentationOffset =
|
|
Offset + static_cast<uint32_t>(AugmentationLength);
|
|
|
|
// Decode the LSDA if the CIE augmentation string said we should.
|
|
if (Cie->getLSDAPointerEncoding() != DW_EH_PE_omit)
|
|
readPointer(Data, Offset, Cie->getLSDAPointerEncoding());
|
|
|
|
if (Offset != EndAugmentationOffset)
|
|
ReportError("Parsing augmentation data at %lx failed");
|
|
}
|
|
} else {
|
|
InitialLocation = Data.getAddress(&Offset);
|
|
AddressRange = Data.getAddress(&Offset);
|
|
}
|
|
|
|
Entries.emplace_back(new FDE(StartOffset, Length, CIEPointer,
|
|
InitialLocation, AddressRange,
|
|
Cie));
|
|
}
|
|
|
|
Entries.back()->parseInstructions(Data, &Offset, EndStructureOffset);
|
|
|
|
if (Offset != EndStructureOffset)
|
|
ReportError("Parsing entry instructions at %lx failed");
|
|
}
|
|
}
|
|
|
|
|
|
void DWARFDebugFrame::dump(raw_ostream &OS) const {
|
|
OS << "\n";
|
|
for (const auto &Entry : Entries) {
|
|
Entry->dumpHeader(OS);
|
|
Entry->dumpInstructions(OS);
|
|
OS << "\n";
|
|
}
|
|
}
|
|
|