bool ObjectContainerUniversalMachO::ParseHeader(
    lldb_private::DataExtractor &data, llvm::MachO::fat_header &header,
    std::vector<llvm::MachO::fat_arch> &fat_archs) {
  bool success = false;
  // Store the file offset for this universal file as we could have a universal
  // .o file
  // in a BSD archive, or be contained in another kind of object.
  // Universal mach-o files always have their headers in big endian.
  lldb::offset_t offset = 0;
  data.SetByteOrder(eByteOrderBig);
  header.magic = data.GetU32(&offset);
  fat_archs.clear();

  if (header.magic == FAT_MAGIC) {

    data.SetAddressByteSize(4);

    header.nfat_arch = data.GetU32(&offset);

    // Now we should have enough data for all of the fat headers, so lets index
    // them so we know how many architectures that this universal binary
    // contains.
    uint32_t arch_idx = 0;
    for (arch_idx = 0; arch_idx < header.nfat_arch; ++arch_idx) {
      if (data.ValidOffsetForDataOfSize(offset, sizeof(fat_arch))) {
        fat_arch arch;
        if (data.GetU32(&offset, &arch, sizeof(fat_arch) / sizeof(uint32_t)))
          fat_archs.push_back(arch);
      }
    }
    success = true;
  } else {
    memset(&header, 0, sizeof(header));
  }
  return success;
}
    virtual size_t
    Decode (const lldb_private::Disassembler &disassembler,
            const lldb_private::DataExtractor &data,
            lldb::offset_t data_offset)
    {
        // All we have to do is read the opcode which can be easy for some
        // architectures
        bool got_op = false;
        DisassemblerLLVMC &llvm_disasm = GetDisassemblerLLVMC();
        const ArchSpec &arch = llvm_disasm.GetArchitecture();
        const lldb::ByteOrder byte_order = data.GetByteOrder();
        
        const uint32_t min_op_byte_size = arch.GetMinimumOpcodeByteSize();
        const uint32_t max_op_byte_size = arch.GetMaximumOpcodeByteSize();
        if (min_op_byte_size == max_op_byte_size)
        {
            // Fixed size instructions, just read that amount of data.
            if (!data.ValidOffsetForDataOfSize(data_offset, min_op_byte_size))
                return false;

            switch (min_op_byte_size)
            {
                case 1:
                    m_opcode.SetOpcode8  (data.GetU8  (&data_offset), byte_order);
                    got_op = true;
                    break;

                case 2:
                    m_opcode.SetOpcode16 (data.GetU16 (&data_offset), byte_order);
                    got_op = true;
                    break;

                case 4:
                    m_opcode.SetOpcode32 (data.GetU32 (&data_offset), byte_order);
                    got_op = true;
                    break;

                case 8:
                    m_opcode.SetOpcode64 (data.GetU64 (&data_offset), byte_order);
                    got_op = true;
                    break;

                default:
                    m_opcode.SetOpcodeBytes(data.PeekData(data_offset, min_op_byte_size), min_op_byte_size);
                    got_op = true;
                    break;
            }
        }
        if (!got_op)
        {
            bool is_alternate_isa = false;
            DisassemblerLLVMC::LLVMCDisassembler *mc_disasm_ptr = GetDisasmToUse (is_alternate_isa);
            
            const llvm::Triple::ArchType machine = arch.GetMachine();
            if (machine == llvm::Triple::arm || machine == llvm::Triple::thumb)
            {
                if (machine == llvm::Triple::thumb || is_alternate_isa)
                {
                    uint32_t thumb_opcode = data.GetU16(&data_offset);
                    if ((thumb_opcode & 0xe000) != 0xe000 || ((thumb_opcode & 0x1800u) == 0))
                    {
                        m_opcode.SetOpcode16 (thumb_opcode, byte_order);
                        m_is_valid = true;
                    }
                    else
                    {
                        thumb_opcode <<= 16;
                        thumb_opcode |= data.GetU16(&data_offset);
                        m_opcode.SetOpcode16_2 (thumb_opcode, byte_order);
                        m_is_valid = true;
                    }
                }
                else
                {
                    m_opcode.SetOpcode32 (data.GetU32(&data_offset), byte_order);
                    m_is_valid = true;
                }
            }
            else
            {
                // The opcode isn't evenly sized, so we need to actually use the llvm
                // disassembler to parse it and get the size.
                uint8_t *opcode_data = const_cast<uint8_t *>(data.PeekData (data_offset, 1));
                const size_t opcode_data_len = data.BytesLeft(data_offset);
                const addr_t pc = m_address.GetFileAddress();
                llvm::MCInst inst;
                
                llvm_disasm.Lock(this, NULL);
                const size_t inst_size = mc_disasm_ptr->GetMCInst(opcode_data,
                                                                  opcode_data_len,
                                                                  pc,
                                                                  inst);
                llvm_disasm.Unlock();
                if (inst_size == 0)
                    m_opcode.Clear();
                else
                {
                    m_opcode.SetOpcodeBytes(opcode_data, inst_size);
                    m_is_valid = true;
                }
            }
        }
        return m_opcode.GetByteSize();
    }
示例#3
0
    virtual size_t
    Decode (const lldb_private::Disassembler &disassembler,
            const lldb_private::DataExtractor &data,
            uint32_t data_offset)
    {
        // All we have to do is read the opcode which can be easy for some
        // architetures
        bool got_op = false;
        const ArchSpec &arch = m_disasm.GetArchitecture();
        
        const uint32_t min_op_byte_size = arch.GetMinimumOpcodeByteSize();
        const uint32_t max_op_byte_size = arch.GetMaximumOpcodeByteSize();
        if (min_op_byte_size == max_op_byte_size)
        {
            // Fixed size instructions, just read that amount of data.
            if (!data.ValidOffsetForDataOfSize(data_offset, min_op_byte_size))
                return false;
            
            switch (min_op_byte_size)
            {
                case 1:
                    m_opcode.SetOpcode8  (data.GetU8  (&data_offset));
                    got_op = true;
                    break;

                case 2:
                    m_opcode.SetOpcode16 (data.GetU16 (&data_offset));
                    got_op = true;
                    break;

                case 4:
                    m_opcode.SetOpcode32 (data.GetU32 (&data_offset));
                    got_op = true;
                    break;

                case 8:
                    m_opcode.SetOpcode64 (data.GetU64 (&data_offset));
                    got_op = true;
                    break;

                default:
                    m_opcode.SetOpcodeBytes(data.PeekData(data_offset, min_op_byte_size), min_op_byte_size);
                    got_op = true;
                    break;
            }
        }
        if (!got_op)
        {
            ::LLVMDisasmContextRef disasm_context = m_disasm.m_disasm_context;
            
            bool is_altnernate_isa = false;
            if (m_disasm.m_alternate_disasm_context)
            {
                const AddressClass address_class = GetAddressClass ();
            
                if (address_class == eAddressClassCodeAlternateISA)
                {
                    disasm_context = m_disasm.m_alternate_disasm_context;
                    is_altnernate_isa = true;
                }
            }
            const llvm::Triple::ArchType machine = arch.GetMachine();
            if (machine == llvm::Triple::arm || machine == llvm::Triple::thumb)
            {
                if (machine == llvm::Triple::thumb || is_altnernate_isa)
                {
                    uint32_t thumb_opcode = data.GetU16(&data_offset);
                    if ((thumb_opcode & 0xe000) != 0xe000 || ((thumb_opcode & 0x1800u) == 0))
                    {
                        m_opcode.SetOpcode16 (thumb_opcode);
                    }
                    else
                    {
                        thumb_opcode <<= 16;
                        thumb_opcode |= data.GetU16(&data_offset);
                        m_opcode.SetOpcode32 (thumb_opcode);
                        m_is_valid = true;
                    }
                }
                else
                {
                    m_opcode.SetOpcode32 (data.GetU32(&data_offset));
                }
            }
            else
            {
                // The opcode isn't evenly sized, so we need to actually use the llvm
                // disassembler to parse it and get the size.
                char out_string[512];
                m_disasm.Lock(this, NULL);
                uint8_t *opcode_data = const_cast<uint8_t *>(data.PeekData (data_offset, 1));
                const size_t opcode_data_len = data.GetByteSize() - data_offset;
                const addr_t pc = m_address.GetFileAddress();
                const size_t inst_size = ::LLVMDisasmInstruction (disasm_context,
                                                                  opcode_data,
                                                                  opcode_data_len,
                                                                  pc, // PC value
                                                                  out_string,
                                                                  sizeof(out_string));
                // The address lookup function could have caused us to fill in our comment
                m_comment.clear();
                m_disasm.Unlock();
                if (inst_size == 0)
                    m_opcode.Clear();
                else
                {
                    m_opcode.SetOpcodeBytes(opcode_data, inst_size);
                    m_is_valid = true;
                }
            }
        }
        return m_opcode.GetByteSize();
    }