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//===-- DisassemblerLLVMC.cpp ---------------------------------------------===//
//
// 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 "DisassemblerLLVMC.h"
#include "llvm-c/Disassembler.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDisassembler/MCDisassembler.h"
#include "llvm/MC/MCDisassembler/MCExternalSymbolizer.h"
#include "llvm/MC/MCDisassembler/MCRelocationInfo.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCTargetOptions.h"
#include "llvm/MC/TargetRegistry.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ScopedPrinter.h"
#include "llvm/Support/TargetSelect.h"
#include "lldb/Core/Address.h"
#include "lldb/Core/Module.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/DataExtractor.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/RegularExpression.h"
#include "lldb/Utility/Stream.h"
using namespace lldb;
using namespace lldb_private;
LLDB_PLUGIN_DEFINE(DisassemblerLLVMC)
class DisassemblerLLVMC::MCDisasmInstance {
public:
static std::unique_ptr<MCDisasmInstance>
Create(const char *triple, const char *cpu, const char *features_str,
unsigned flavor, DisassemblerLLVMC &owner);
~MCDisasmInstance() = default;
uint64_t GetMCInst(const uint8_t *opcode_data, size_t opcode_data_len,
lldb::addr_t pc, llvm::MCInst &mc_inst) const;
void PrintMCInst(llvm::MCInst &mc_inst, std::string &inst_string,
std::string &comments_string);
void SetStyle(bool use_hex_immed, HexImmediateStyle hex_style);
bool CanBranch(llvm::MCInst &mc_inst) const;
bool HasDelaySlot(llvm::MCInst &mc_inst) const;
bool IsCall(llvm::MCInst &mc_inst) const;
bool IsLoad(llvm::MCInst &mc_inst) const;
bool IsAuthenticated(llvm::MCInst &mc_inst) const;
private:
MCDisasmInstance(std::unique_ptr<llvm::MCInstrInfo> &&instr_info_up,
std::unique_ptr<llvm::MCRegisterInfo> &&reg_info_up,
std::unique_ptr<llvm::MCSubtargetInfo> &&subtarget_info_up,
std::unique_ptr<llvm::MCAsmInfo> &&asm_info_up,
std::unique_ptr<llvm::MCContext> &&context_up,
std::unique_ptr<llvm::MCDisassembler> &&disasm_up,
std::unique_ptr<llvm::MCInstPrinter> &&instr_printer_up);
std::unique_ptr<llvm::MCInstrInfo> m_instr_info_up;
std::unique_ptr<llvm::MCRegisterInfo> m_reg_info_up;
std::unique_ptr<llvm::MCSubtargetInfo> m_subtarget_info_up;
std::unique_ptr<llvm::MCAsmInfo> m_asm_info_up;
std::unique_ptr<llvm::MCContext> m_context_up;
std::unique_ptr<llvm::MCDisassembler> m_disasm_up;
std::unique_ptr<llvm::MCInstPrinter> m_instr_printer_up;
};
class InstructionLLVMC : public lldb_private::Instruction {
public:
InstructionLLVMC(DisassemblerLLVMC &disasm,
const lldb_private::Address &address,
AddressClass addr_class)
: Instruction(address, addr_class),
m_disasm_wp(std::static_pointer_cast<DisassemblerLLVMC>(
disasm.shared_from_this())),
m_using_file_addr(false) {}
~InstructionLLVMC() override = default;
bool DoesBranch() override {
VisitInstruction();
return m_does_branch;
}
bool HasDelaySlot() override {
VisitInstruction();
return m_has_delay_slot;
}
bool IsLoad() override {
VisitInstruction();
return m_is_load;
}
bool IsAuthenticated() override {
VisitInstruction();
return m_is_authenticated;
}
DisassemblerLLVMC::MCDisasmInstance *GetDisasmToUse(bool &is_alternate_isa) {
DisassemblerScope disasm(*this);
return GetDisasmToUse(is_alternate_isa, disasm);
}
size_t Decode(const lldb_private::Disassembler &disassembler,
const lldb_private::DataExtractor &data,
lldb::offset_t data_offset) override {
// All we have to do is read the opcode which can be easy for some
// architectures
bool got_op = false;
DisassemblerScope disasm(*this);
if (disasm) {
const ArchSpec &arch = 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::MCDisasmInstance *mc_disasm_ptr =
GetDisasmToUse(is_alternate_isa, disasm);
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;
const size_t inst_size =
mc_disasm_ptr->GetMCInst(opcode_data, opcode_data_len, pc, inst);
if (inst_size == 0)
m_opcode.Clear();
else {
m_opcode.SetOpcodeBytes(opcode_data, inst_size);
m_is_valid = true;
}
}
}
return m_opcode.GetByteSize();
}
return 0;
}
void AppendComment(std::string &description) {
if (m_comment.empty())
m_comment.swap(description);
else {
m_comment.append(", ");
m_comment.append(description);
}
}
void CalculateMnemonicOperandsAndComment(
const lldb_private::ExecutionContext *exe_ctx) override {
DataExtractor data;
const AddressClass address_class = GetAddressClass();
if (m_opcode.GetData(data)) {
std::string out_string;
std::string comment_string;
DisassemblerScope disasm(*this, exe_ctx);
if (disasm) {
DisassemblerLLVMC::MCDisasmInstance *mc_disasm_ptr;
if (address_class == AddressClass::eCodeAlternateISA)
mc_disasm_ptr = disasm->m_alternate_disasm_up.get();
else
mc_disasm_ptr = disasm->m_disasm_up.get();
lldb::addr_t pc = m_address.GetFileAddress();
m_using_file_addr = true;
const bool data_from_file = disasm->m_data_from_file;
bool use_hex_immediates = true;
Disassembler::HexImmediateStyle hex_style = Disassembler::eHexStyleC;
if (exe_ctx) {
Target *target = exe_ctx->GetTargetPtr();
if (target) {
use_hex_immediates = target->GetUseHexImmediates();
hex_style = target->GetHexImmediateStyle();
if (!data_from_file) {
const lldb::addr_t load_addr = m_address.GetLoadAddress(target);
if (load_addr != LLDB_INVALID_ADDRESS) {
pc = load_addr;
m_using_file_addr = false;
}
}
}
}
const uint8_t *opcode_data = data.GetDataStart();
const size_t opcode_data_len = data.GetByteSize();
llvm::MCInst inst;
size_t inst_size =
mc_disasm_ptr->GetMCInst(opcode_data, opcode_data_len, pc, inst);
if (inst_size > 0) {
mc_disasm_ptr->SetStyle(use_hex_immediates, hex_style);
mc_disasm_ptr->PrintMCInst(inst, out_string, comment_string);
if (!comment_string.empty()) {
AppendComment(comment_string);
}
}
if (inst_size == 0) {
m_comment.assign("unknown opcode");
inst_size = m_opcode.GetByteSize();
StreamString mnemonic_strm;
lldb::offset_t offset = 0;
lldb::ByteOrder byte_order = data.GetByteOrder();
switch (inst_size) {
case 1: {
const uint8_t uval8 = data.GetU8(&offset);
m_opcode.SetOpcode8(uval8, byte_order);
m_opcode_name.assign(".byte");
mnemonic_strm.Printf("0x%2.2x", uval8);
} break;
case 2: {
const uint16_t uval16 = data.GetU16(&offset);
m_opcode.SetOpcode16(uval16, byte_order);
m_opcode_name.assign(".short");
mnemonic_strm.Printf("0x%4.4x", uval16);
} break;
case 4: {
const uint32_t uval32 = data.GetU32(&offset);
m_opcode.SetOpcode32(uval32, byte_order);
m_opcode_name.assign(".long");
mnemonic_strm.Printf("0x%8.8x", uval32);
} break;
case 8: {
const uint64_t uval64 = data.GetU64(&offset);
m_opcode.SetOpcode64(uval64, byte_order);
m_opcode_name.assign(".quad");
mnemonic_strm.Printf("0x%16.16" PRIx64, uval64);
} break;
default:
if (inst_size == 0)
return;
else {
const uint8_t *bytes = data.PeekData(offset, inst_size);
if (bytes == nullptr)
return;
m_opcode_name.assign(".byte");
m_opcode.SetOpcodeBytes(bytes, inst_size);
mnemonic_strm.Printf("0x%2.2x", bytes[0]);
for (uint32_t i = 1; i < inst_size; ++i)
mnemonic_strm.Printf(" 0x%2.2x", bytes[i]);
}
break;
}
m_mnemonics = std::string(mnemonic_strm.GetString());
return;
}
static RegularExpression s_regex(
llvm::StringRef("[ \t]*([^ ^\t]+)[ \t]*([^ ^\t].*)?"));
llvm::SmallVector<llvm::StringRef, 4> matches;
if (s_regex.Execute(out_string, &matches)) {
m_opcode_name = matches[1].str();
m_mnemonics = matches[2].str();
}
}
}
}
bool IsValid() const { return m_is_valid; }
bool UsingFileAddress() const { return m_using_file_addr; }
size_t GetByteSize() const { return m_opcode.GetByteSize(); }
/// Grants exclusive access to the disassembler and initializes it with the
/// given InstructionLLVMC and an optional ExecutionContext.
class DisassemblerScope {
std::shared_ptr<DisassemblerLLVMC> m_disasm;
public:
explicit DisassemblerScope(
InstructionLLVMC &i,
const lldb_private::ExecutionContext *exe_ctx = nullptr)
: m_disasm(i.m_disasm_wp.lock()) {
m_disasm->m_mutex.lock();
m_disasm->m_inst = &i;
m_disasm->m_exe_ctx = exe_ctx;
}
~DisassemblerScope() { m_disasm->m_mutex.unlock(); }
/// Evaluates to true if this scope contains a valid disassembler.
operator bool() const { return static_cast<bool>(m_disasm); }
std::shared_ptr<DisassemblerLLVMC> operator->() { return m_disasm; }
};
static llvm::StringRef::const_iterator
ConsumeWhitespace(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
while (osi != ose) {
switch (*osi) {
default:
return osi;
case ' ':
case '\t':
break;
}
++osi;
}
return osi;
}
static std::pair<bool, llvm::StringRef::const_iterator>
ConsumeChar(llvm::StringRef::const_iterator osi, const char c,
llvm::StringRef::const_iterator ose) {
bool found = false;
osi = ConsumeWhitespace(osi, ose);
if (osi != ose && *osi == c) {
found = true;
++osi;
}
return std::make_pair(found, osi);
}
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseRegisterName(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
Operand ret;
ret.m_type = Operand::Type::Register;
std::string str;
osi = ConsumeWhitespace(osi, ose);
while (osi != ose) {
if (*osi >= '0' && *osi <= '9') {
if (str.empty()) {
return std::make_pair(Operand(), osi);
} else {
str.push_back(*osi);
}
} else if (*osi >= 'a' && *osi <= 'z') {
str.push_back(*osi);
} else {
switch (*osi) {
default:
if (str.empty()) {
return std::make_pair(Operand(), osi);
} else {
ret.m_register = ConstString(str);
return std::make_pair(ret, osi);
}
case '%':
if (!str.empty()) {
return std::make_pair(Operand(), osi);
}
break;
}
}
++osi;
}
ret.m_register = ConstString(str);
return std::make_pair(ret, osi);
}
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseImmediate(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
Operand ret;
ret.m_type = Operand::Type::Immediate;
std::string str;
bool is_hex = false;
osi = ConsumeWhitespace(osi, ose);
while (osi != ose) {
if (*osi >= '0' && *osi <= '9') {
str.push_back(*osi);
} else if (*osi >= 'a' && *osi <= 'f') {
if (is_hex) {
str.push_back(*osi);
} else {
return std::make_pair(Operand(), osi);
}
} else {
switch (*osi) {
default:
if (str.empty()) {
return std::make_pair(Operand(), osi);
} else {
ret.m_immediate = strtoull(str.c_str(), nullptr, 0);
return std::make_pair(ret, osi);
}
case 'x':
if (!str.compare("0")) {
is_hex = true;
str.push_back(*osi);
} else {
return std::make_pair(Operand(), osi);
}
break;
case '#':
case '$':
if (!str.empty()) {
return std::make_pair(Operand(), osi);
}
break;
case '-':
if (str.empty()) {
ret.m_negative = true;
} else {
return std::make_pair(Operand(), osi);
}
}
}
++osi;
}
ret.m_immediate = strtoull(str.c_str(), nullptr, 0);
return std::make_pair(ret, osi);
}
// -0x5(%rax,%rax,2)
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseIntelIndexedAccess(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
std::pair<Operand, llvm::StringRef::const_iterator> offset_and_iterator =
ParseImmediate(osi, ose);
if (offset_and_iterator.first.IsValid()) {
osi = offset_and_iterator.second;
}
bool found = false;
std::tie(found, osi) = ConsumeChar(osi, '(', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> base_and_iterator =
ParseRegisterName(osi, ose);
if (base_and_iterator.first.IsValid()) {
osi = base_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ',', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> index_and_iterator =
ParseRegisterName(osi, ose);
if (index_and_iterator.first.IsValid()) {
osi = index_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ',', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator>
multiplier_and_iterator = ParseImmediate(osi, ose);
if (index_and_iterator.first.IsValid()) {
osi = index_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ')', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
Operand product;
product.m_type = Operand::Type::Product;
product.m_children.push_back(index_and_iterator.first);
product.m_children.push_back(multiplier_and_iterator.first);
Operand index;
index.m_type = Operand::Type::Sum;
index.m_children.push_back(base_and_iterator.first);
index.m_children.push_back(product);
if (offset_and_iterator.first.IsValid()) {
Operand offset;
offset.m_type = Operand::Type::Sum;
offset.m_children.push_back(offset_and_iterator.first);
offset.m_children.push_back(index);
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(offset);
return std::make_pair(deref, osi);
} else {
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(index);
return std::make_pair(deref, osi);
}
}
// -0x10(%rbp)
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseIntelDerefAccess(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
std::pair<Operand, llvm::StringRef::const_iterator> offset_and_iterator =
ParseImmediate(osi, ose);
if (offset_and_iterator.first.IsValid()) {
osi = offset_and_iterator.second;
}
bool found = false;
std::tie(found, osi) = ConsumeChar(osi, '(', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> base_and_iterator =
ParseRegisterName(osi, ose);
if (base_and_iterator.first.IsValid()) {
osi = base_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ')', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
if (offset_and_iterator.first.IsValid()) {
Operand offset;
offset.m_type = Operand::Type::Sum;
offset.m_children.push_back(offset_and_iterator.first);
offset.m_children.push_back(base_and_iterator.first);
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(offset);
return std::make_pair(deref, osi);
} else {
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(base_and_iterator.first);
return std::make_pair(deref, osi);
}
}
// [sp, #8]!
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseARMOffsetAccess(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
bool found = false;
std::tie(found, osi) = ConsumeChar(osi, '[', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> base_and_iterator =
ParseRegisterName(osi, ose);
if (base_and_iterator.first.IsValid()) {
osi = base_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ',', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> offset_and_iterator =
ParseImmediate(osi, ose);
if (offset_and_iterator.first.IsValid()) {
osi = offset_and_iterator.second;
}
std::tie(found, osi) = ConsumeChar(osi, ']', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
Operand offset;
offset.m_type = Operand::Type::Sum;
offset.m_children.push_back(offset_and_iterator.first);
offset.m_children.push_back(base_and_iterator.first);
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(offset);
return std::make_pair(deref, osi);
}
// [sp]
static std::pair<Operand, llvm::StringRef::const_iterator>
ParseARMDerefAccess(llvm::StringRef::const_iterator osi,
llvm::StringRef::const_iterator ose) {
bool found = false;
std::tie(found, osi) = ConsumeChar(osi, '[', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
std::pair<Operand, llvm::StringRef::const_iterator> base_and_iterator =
ParseRegisterName(osi, ose);
if (base_and_iterator.first.IsValid()) {
osi = base_and_iterator.second;
} else {
return std::make_pair(Operand(), osi);
}
std::tie(found, osi) = ConsumeChar(osi, ']', ose);
if (!found) {
return std::make_pair(Operand(), osi);
}
Operand deref;
deref.m_type = Operand::Type::Dereference;
deref.m_children.push_back(base_and_iterator.first);
return std::make_pair(deref, osi);
}
static void DumpOperand(const Operand &op, Stream &s) {
switch (op.m_type) {
case Operand::Type::Dereference:
s.PutCString("*");
DumpOperand(op.m_children[0], s);
break;
case Operand::Type::Immediate:
if (op.m_negative) {
s.PutCString("-");
}
s.PutCString(llvm::to_string(op.m_immediate));
break;
case Operand::Type::Invalid:
s.PutCString("Invalid");
break;
case Operand::Type::Product:
s.PutCString("(");
DumpOperand(op.m_children[0], s);
s.PutCString("*");
DumpOperand(op.m_children[1], s);
s.PutCString(")");
break;
case Operand::Type::Register:
s.PutCString(op.m_register.GetStringRef());
break;
case Operand::Type::Sum:
s.PutCString("(");
DumpOperand(op.m_children[0], s);
s.PutCString("+");
DumpOperand(op.m_children[1], s);
s.PutCString(")");
break;
}
}
bool ParseOperands(
llvm::SmallVectorImpl<Instruction::Operand> &operands) override {
const char *operands_string = GetOperands(nullptr);
if (!operands_string) {
return false;
}
llvm::StringRef operands_ref(operands_string);
llvm::StringRef::const_iterator osi = operands_ref.begin();
llvm::StringRef::const_iterator ose = operands_ref.end();
while (osi != ose) {
Operand operand;
llvm::StringRef::const_iterator iter;
if ((std::tie(operand, iter) = ParseIntelIndexedAccess(osi, ose),
operand.IsValid()) ||
(std::tie(operand, iter) = ParseIntelDerefAccess(osi, ose),
operand.IsValid()) ||
(std::tie(operand, iter) = ParseARMOffsetAccess(osi, ose),
operand.IsValid()) ||
(std::tie(operand, iter) = ParseARMDerefAccess(osi, ose),
operand.IsValid()) ||
(std::tie(operand, iter) = ParseRegisterName(osi, ose),
operand.IsValid()) ||
(std::tie(operand, iter) = ParseImmediate(osi, ose),
operand.IsValid())) {
osi = iter;
operands.push_back(operand);
} else {
return false;
}
std::pair<bool, llvm::StringRef::const_iterator> found_and_iter =
ConsumeChar(osi, ',', ose);
if (found_and_iter.first) {
osi = found_and_iter.second;
}
osi = ConsumeWhitespace(osi, ose);
}
DisassemblerSP disasm_sp = m_disasm_wp.lock();
if (disasm_sp && operands.size() > 1) {
// TODO tie this into the MC Disassembler's notion of clobbers.
switch (disasm_sp->GetArchitecture().GetMachine()) {
default:
break;
case llvm::Triple::x86:
case llvm::Triple::x86_64:
operands[operands.size() - 1].m_clobbered = true;
break;
case llvm::Triple::arm:
operands[0].m_clobbered = true;
break;
}
}
if (Log *log =
lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)) {
StreamString ss;
ss.Printf("[%s] expands to %zu operands:\n", operands_string,
operands.size());
for (const Operand &operand : operands) {
ss.PutCString(" ");
DumpOperand(operand, ss);
ss.PutCString("\n");
}
log->PutString(ss.GetString());
}
return true;
}
bool IsCall() override {
VisitInstruction();
return m_is_call;
}
protected:
std::weak_ptr<DisassemblerLLVMC> m_disasm_wp;
bool m_is_valid = false;
bool m_using_file_addr;
bool m_has_visited_instruction = false;
// Be conservative. If we didn't understand the instruction, say it:
// - Might branch
// - Does not have a delay slot
// - Is not a call
// - Is not a load
// - Is not an authenticated instruction
bool m_does_branch = true;
bool m_has_delay_slot = false;
bool m_is_call = false;
bool m_is_load = false;
bool m_is_authenticated = false;
void VisitInstruction() {
if (m_has_visited_instruction)
return;
DisassemblerScope disasm(*this);
if (!disasm)
return;
DataExtractor data;
if (!m_opcode.GetData(data))
return;
bool is_alternate_isa;
lldb::addr_t pc = m_address.GetFileAddress();
DisassemblerLLVMC::MCDisasmInstance *mc_disasm_ptr =
GetDisasmToUse(is_alternate_isa, disasm);
const uint8_t *opcode_data = data.GetDataStart();
const size_t opcode_data_len = data.GetByteSize();
llvm::MCInst inst;
const size_t inst_size =
mc_disasm_ptr->GetMCInst(opcode_data, opcode_data_len, pc, inst);
if (inst_size == 0)
return;
m_has_visited_instruction = true;
m_does_branch = mc_disasm_ptr->CanBranch(inst);
m_has_delay_slot = mc_disasm_ptr->HasDelaySlot(inst);
m_is_call = mc_disasm_ptr->IsCall(inst);
m_is_load = mc_disasm_ptr->IsLoad(inst);
m_is_authenticated = mc_disasm_ptr->IsAuthenticated(inst);
}
private:
DisassemblerLLVMC::MCDisasmInstance *
GetDisasmToUse(bool &is_alternate_isa, DisassemblerScope &disasm) {
is_alternate_isa = false;
if (disasm) {
if (disasm->m_alternate_disasm_up) {
const AddressClass address_class = GetAddressClass();
if (address_class == AddressClass::eCodeAlternateISA) {
is_alternate_isa = true;
return disasm->m_alternate_disasm_up.get();
}
}
return disasm->m_disasm_up.get();
}
return nullptr;
}
};
std::unique_ptr<DisassemblerLLVMC::MCDisasmInstance>
DisassemblerLLVMC::MCDisasmInstance::Create(const char *triple, const char *cpu,
const char *features_str,
unsigned flavor,
DisassemblerLLVMC &owner) {
using Instance = std::unique_ptr<DisassemblerLLVMC::MCDisasmInstance>;
std::string Status;
const llvm::Target *curr_target =
llvm::TargetRegistry::lookupTarget(triple, Status);
if (!curr_target)
return Instance();
std::unique_ptr<llvm::MCInstrInfo> instr_info_up(
curr_target->createMCInstrInfo());
if (!instr_info_up)
return Instance();
std::unique_ptr<llvm::MCRegisterInfo> reg_info_up(
curr_target->createMCRegInfo(triple));
if (!reg_info_up)
return Instance();
std::unique_ptr<llvm::MCSubtargetInfo> subtarget_info_up(
curr_target->createMCSubtargetInfo(triple, cpu, features_str));
if (!subtarget_info_up)
return Instance();
llvm::MCTargetOptions MCOptions;
std::unique_ptr<llvm::MCAsmInfo> asm_info_up(
curr_target->createMCAsmInfo(*reg_info_up, triple, MCOptions));
if (!asm_info_up)
return Instance();
std::unique_ptr<llvm::MCContext> context_up(
new llvm::MCContext(llvm::Triple(triple), asm_info_up.get(),
reg_info_up.get(), subtarget_info_up.get()));
if (!context_up)
return Instance();
std::unique_ptr<llvm::MCDisassembler> disasm_up(
curr_target->createMCDisassembler(*subtarget_info_up, *context_up));
if (!disasm_up)
return Instance();
std::unique_ptr<llvm::MCRelocationInfo> rel_info_up(
curr_target->createMCRelocationInfo(triple, *context_up));
if (!rel_info_up)
return Instance();
std::unique_ptr<llvm::MCSymbolizer> symbolizer_up(
curr_target->createMCSymbolizer(
triple, nullptr, DisassemblerLLVMC::SymbolLookupCallback, &owner,
context_up.get(), std::move(rel_info_up)));
disasm_up->setSymbolizer(std::move(symbolizer_up));
unsigned asm_printer_variant =
flavor == ~0U ? asm_info_up->getAssemblerDialect() : flavor;
std::unique_ptr<llvm::MCInstPrinter> instr_printer_up(
curr_target->createMCInstPrinter(llvm::Triple{triple},
asm_printer_variant, *asm_info_up,
*instr_info_up, *reg_info_up));
if (!instr_printer_up)
return Instance();
return Instance(
new MCDisasmInstance(std::move(instr_info_up), std::move(reg_info_up),
std::move(subtarget_info_up), std::move(asm_info_up),
std::move(context_up), std::move(disasm_up),
std::move(instr_printer_up)));
}
DisassemblerLLVMC::MCDisasmInstance::MCDisasmInstance(
std::unique_ptr<llvm::MCInstrInfo> &&instr_info_up,
std::unique_ptr<llvm::MCRegisterInfo> &&reg_info_up,
std::unique_ptr<llvm::MCSubtargetInfo> &&subtarget_info_up,
std::unique_ptr<llvm::MCAsmInfo> &&asm_info_up,
std::unique_ptr<llvm::MCContext> &&context_up,
std::unique_ptr<llvm::MCDisassembler> &&disasm_up,
std::unique_ptr<llvm::MCInstPrinter> &&instr_printer_up)
: m_instr_info_up(std::move(instr_info_up)),
m_reg_info_up(std::move(reg_info_up)),
m_subtarget_info_up(std::move(subtarget_info_up)),
m_asm_info_up(std::move(asm_info_up)),
m_context_up(std::move(context_up)), m_disasm_up(std::move(disasm_up)),
m_instr_printer_up(std::move(instr_printer_up)) {
assert(m_instr_info_up && m_reg_info_up && m_subtarget_info_up &&
m_asm_info_up && m_context_up && m_disasm_up && m_instr_printer_up);
}
uint64_t DisassemblerLLVMC::MCDisasmInstance::GetMCInst(
const uint8_t *opcode_data, size_t opcode_data_len, lldb::addr_t pc,
llvm::MCInst &mc_inst) const {
llvm::ArrayRef<uint8_t> data(opcode_data, opcode_data_len);
llvm::MCDisassembler::DecodeStatus status;
uint64_t new_inst_size;
status = m_disasm_up->getInstruction(mc_inst, new_inst_size, data, pc,
llvm::nulls());
if (status == llvm::MCDisassembler::Success)
return new_inst_size;
else
return 0;
}
void DisassemblerLLVMC::MCDisasmInstance::PrintMCInst(
llvm::MCInst &mc_inst, std::string &inst_string,
std::string &comments_string) {
llvm::raw_string_ostream inst_stream(inst_string);
llvm::raw_string_ostream comments_stream(comments_string);
m_instr_printer_up->setCommentStream(comments_stream);
m_instr_printer_up->printInst(&mc_inst, 0, llvm::StringRef(),
*m_subtarget_info_up, inst_stream);
m_instr_printer_up->setCommentStream(llvm::nulls());
comments_stream.flush();
static std::string g_newlines("\r\n");
for (size_t newline_pos = 0;
(newline_pos = comments_string.find_first_of(g_newlines, newline_pos)) !=
comments_string.npos;
/**/) {
comments_string.replace(comments_string.begin() + newline_pos,
comments_string.begin() + newline_pos + 1, 1, ' ');
}
}
void DisassemblerLLVMC::MCDisasmInstance::SetStyle(
bool use_hex_immed, HexImmediateStyle hex_style) {
m_instr_printer_up->setPrintImmHex(use_hex_immed);
switch (hex_style) {
case eHexStyleC:
m_instr_printer_up->setPrintHexStyle(llvm::HexStyle::C);
break;
case eHexStyleAsm:
m_instr_printer_up->setPrintHexStyle(llvm::HexStyle::Asm);
break;
}
}
bool DisassemblerLLVMC::MCDisasmInstance::CanBranch(
llvm::MCInst &mc_inst) const {
return m_instr_info_up->get(mc_inst.getOpcode())
.mayAffectControlFlow(mc_inst, *m_reg_info_up);
}
bool DisassemblerLLVMC::MCDisasmInstance::HasDelaySlot(
llvm::MCInst &mc_inst) const {
return m_instr_info_up->get(mc_inst.getOpcode()).hasDelaySlot();
}
bool DisassemblerLLVMC::MCDisasmInstance::IsCall(llvm::MCInst &mc_inst) const {
return m_instr_info_up->get(mc_inst.getOpcode()).isCall();
}
bool DisassemblerLLVMC::MCDisasmInstance::IsLoad(llvm::MCInst &mc_inst) const {
return m_instr_info_up->get(mc_inst.getOpcode()).mayLoad();
}
bool DisassemblerLLVMC::MCDisasmInstance::IsAuthenticated(
llvm::MCInst &mc_inst) const {
auto InstrDesc = m_instr_info_up->get(mc_inst.getOpcode());
// Treat software auth traps (brk 0xc470 + aut key, where 0x70 == 'p', 0xc4
// == 'a' + 'c') as authenticated instructions for reporting purposes, in
// addition to the standard authenticated instructions specified in ARMv8.3.
bool IsBrkC47x = false;
if (InstrDesc.isTrap() && mc_inst.getNumOperands() == 1) {
const llvm::MCOperand &Op0 = mc_inst.getOperand(0);
if (Op0.isImm() && Op0.getImm() >= 0xc470 && Op0.getImm() <= 0xc474)
IsBrkC47x = true;
}
return InstrDesc.isAuthenticated() || IsBrkC47x;
}
DisassemblerLLVMC::DisassemblerLLVMC(const ArchSpec &arch,
const char *flavor_string)
: Disassembler(arch, flavor_string), m_exe_ctx(nullptr), m_inst(nullptr),
m_data_from_file(false), m_adrp_address(LLDB_INVALID_ADDRESS),
m_adrp_insn() {
if (!FlavorValidForArchSpec(arch, m_flavor.c_str())) {
m_flavor.assign("default");
}
unsigned flavor = ~0U;
llvm::Triple triple = arch.GetTriple();
// So far the only supported flavor is "intel" on x86. The base class will
// set this correctly coming in.
if (triple.getArch() == llvm::Triple::x86 ||
triple.getArch() == llvm::Triple::x86_64) {
if (m_flavor == "intel") {
flavor = 1;
} else if (m_flavor == "att") {
flavor = 0;
}
}
ArchSpec thumb_arch(arch);
if (triple.getArch() == llvm::Triple::arm) {
std::string thumb_arch_name(thumb_arch.GetTriple().getArchName().str());
// Replace "arm" with "thumb" so we get all thumb variants correct
if (thumb_arch_name.size() > 3) {
thumb_arch_name.erase(0, 3);
thumb_arch_name.insert(0, "thumb");
} else {
thumb_arch_name = "thumbv8.7a";
}
thumb_arch.GetTriple().setArchName(llvm::StringRef(thumb_arch_name));
}
// If no sub architecture specified then use the most recent arm architecture
// so the disassembler will return all instruction. Without it we will see a
// lot of unknow opcode in case the code uses instructions which are not
// available in the oldest arm version (used when no sub architecture is
// specified)
if (triple.getArch() == llvm::Triple::arm &&
triple.getSubArch() == llvm::Triple::NoSubArch)
triple.setArchName("armv8.7a");
std::string features_str = "";
const char *triple_str = triple.getTriple().c_str();
// ARM Cortex M0-M7 devices only execute thumb instructions
if (arch.IsAlwaysThumbInstructions()) {
triple_str = thumb_arch.GetTriple().getTriple().c_str();
features_str += "+fp-armv8,";
}
const char *cpu = "";
switch (arch.GetCore()) {
case ArchSpec::eCore_mips32:
case ArchSpec::eCore_mips32el:
cpu = "mips32";
break;
case ArchSpec::eCore_mips32r2:
case ArchSpec::eCore_mips32r2el:
cpu = "mips32r2";
break;
case ArchSpec::eCore_mips32r3:
case ArchSpec::eCore_mips32r3el:
cpu = "mips32r3";
break;
case ArchSpec::eCore_mips32r5:
case ArchSpec::eCore_mips32r5el:
cpu = "mips32r5";
break;
case ArchSpec::eCore_mips32r6:
case ArchSpec::eCore_mips32r6el:
cpu = "mips32r6";
break;
case ArchSpec::eCore_mips64:
case ArchSpec::eCore_mips64el:
cpu = "mips64";
break;
case ArchSpec::eCore_mips64r2:
case ArchSpec::eCore_mips64r2el:
cpu = "mips64r2";
break;
case ArchSpec::eCore_mips64r3:
case ArchSpec::eCore_mips64r3el:
cpu = "mips64r3";
break;
case ArchSpec::eCore_mips64r5:
case ArchSpec::eCore_mips64r5el:
cpu = "mips64r5";
break;
case ArchSpec::eCore_mips64r6:
case ArchSpec::eCore_mips64r6el:
cpu = "mips64r6";
break;
default:
cpu = "";
break;
}
if (arch.IsMIPS()) {
uint32_t arch_flags = arch.GetFlags();
if (arch_flags & ArchSpec::eMIPSAse_msa)
features_str += "+msa,";
if (arch_flags & ArchSpec::eMIPSAse_dsp)
features_str += "+dsp,";
if (arch_flags & ArchSpec::eMIPSAse_dspr2)
features_str += "+dspr2,";
}
// If any AArch64 variant, enable latest ISA with any optional
// extensions like SVE.
if (triple.isAArch64()) {
features_str += "+v8.7a,+sve2,+mte";
if (triple.getVendor() == llvm::Triple::Apple)
cpu = "apple-latest";
}
// We use m_disasm_up.get() to tell whether we are valid or not, so if this
// isn't good for some reason, we won't be valid and FindPlugin will fail and
// we won't get used.
m_disasm_up = MCDisasmInstance::Create(triple_str, cpu, features_str.c_str(),
flavor, *this);
llvm::Triple::ArchType llvm_arch = triple.getArch();
// For arm CPUs that can execute arm or thumb instructions, also create a
// thumb instruction disassembler.
if (llvm_arch == llvm::Triple::arm) {
std::string thumb_triple(thumb_arch.GetTriple().getTriple());
m_alternate_disasm_up =
MCDisasmInstance::Create(thumb_triple.c_str(), "", features_str.c_str(),
flavor, *this);
if (!m_alternate_disasm_up)
m_disasm_up.reset();
} else if (arch.IsMIPS()) {
/* Create alternate disassembler for MIPS16 and microMIPS */
uint32_t arch_flags = arch.GetFlags();
if (arch_flags & ArchSpec::eMIPSAse_mips16)
features_str += "+mips16,";
else if (arch_flags & ArchSpec::eMIPSAse_micromips)
features_str += "+micromips,";
m_alternate_disasm_up = MCDisasmInstance::Create(
triple_str, cpu, features_str.c_str(), flavor, *this);
if (!m_alternate_disasm_up)
m_disasm_up.reset();
}
}
DisassemblerLLVMC::~DisassemblerLLVMC() = default;
Disassembler *DisassemblerLLVMC::CreateInstance(const ArchSpec &arch,
const char *flavor) {
if (arch.GetTriple().getArch() != llvm::Triple::UnknownArch) {
std::unique_ptr<DisassemblerLLVMC> disasm_up(
new DisassemblerLLVMC(arch, flavor));
if (disasm_up.get() && disasm_up->IsValid())
return disasm_up.release();
}
return nullptr;
}
size_t DisassemblerLLVMC::DecodeInstructions(const Address &base_addr,
const DataExtractor &data,
lldb::offset_t data_offset,
size_t num_instructions,
bool append, bool data_from_file) {
if (!append)
m_instruction_list.Clear();
if (!IsValid())
return 0;
m_data_from_file = data_from_file;
uint32_t data_cursor = data_offset;
const size_t data_byte_size = data.GetByteSize();
uint32_t instructions_parsed = 0;
Address inst_addr(base_addr);
while (data_cursor < data_byte_size &&
instructions_parsed < num_instructions) {
AddressClass address_class = AddressClass::eCode;
if (m_alternate_disasm_up)
address_class = inst_addr.GetAddressClass();
InstructionSP inst_sp(
new InstructionLLVMC(*this, inst_addr, address_class));
if (!inst_sp)
break;
uint32_t inst_size = inst_sp->Decode(*this, data, data_cursor);
if (inst_size == 0)
break;
m_instruction_list.Append(inst_sp);
data_cursor += inst_size;
inst_addr.Slide(inst_size);
instructions_parsed++;
}
return data_cursor - data_offset;
}
void DisassemblerLLVMC::Initialize() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
"Disassembler that uses LLVM MC to disassemble "
"i386, x86_64, ARM, and ARM64.",
CreateInstance);
llvm::InitializeAllTargetInfos();
llvm::InitializeAllTargetMCs();
llvm::InitializeAllAsmParsers();
llvm::InitializeAllDisassemblers();
}
void DisassemblerLLVMC::Terminate() {
PluginManager::UnregisterPlugin(CreateInstance);
}
int DisassemblerLLVMC::OpInfoCallback(void *disassembler, uint64_t pc,
uint64_t offset, uint64_t size,
int tag_type, void *tag_bug) {
return static_cast<DisassemblerLLVMC *>(disassembler)
->OpInfo(pc, offset, size, tag_type, tag_bug);
}
const char *DisassemblerLLVMC::SymbolLookupCallback(void *disassembler,
uint64_t value,
uint64_t *type, uint64_t pc,
const char **name) {
return static_cast<DisassemblerLLVMC *>(disassembler)
->SymbolLookup(value, type, pc, name);
}
bool DisassemblerLLVMC::FlavorValidForArchSpec(
const lldb_private::ArchSpec &arch, const char *flavor) {
llvm::Triple triple = arch.GetTriple();
if (flavor == nullptr || strcmp(flavor, "default") == 0)
return true;
if (triple.getArch() == llvm::Triple::x86 ||
triple.getArch() == llvm::Triple::x86_64) {
return strcmp(flavor, "intel") == 0 || strcmp(flavor, "att") == 0;
} else
return false;
}
bool DisassemblerLLVMC::IsValid() const { return m_disasm_up.operator bool(); }
int DisassemblerLLVMC::OpInfo(uint64_t PC, uint64_t Offset, uint64_t Size,
int tag_type, void *tag_bug) {
switch (tag_type) {
default:
break;
case 1:
memset(tag_bug, 0, sizeof(::LLVMOpInfo1));
break;
}
return 0;
}
const char *DisassemblerLLVMC::SymbolLookup(uint64_t value, uint64_t *type_ptr,
uint64_t pc, const char **name) {
if (*type_ptr) {
if (m_exe_ctx && m_inst) {
// std::string remove_this_prior_to_checkin;
Target *target = m_exe_ctx ? m_exe_ctx->GetTargetPtr() : nullptr;
Address value_so_addr;
Address pc_so_addr;
if (target->GetArchitecture().GetMachine() == llvm::Triple::aarch64 ||
target->GetArchitecture().GetMachine() == llvm::Triple::aarch64_be ||
target->GetArchitecture().GetMachine() == llvm::Triple::aarch64_32) {
if (*type_ptr == LLVMDisassembler_ReferenceType_In_ARM64_ADRP) {
m_adrp_address = pc;
m_adrp_insn = value;
*name = nullptr;
*type_ptr = LLVMDisassembler_ReferenceType_InOut_None;
return nullptr;
}
// If this instruction is an ADD and
// the previous instruction was an ADRP and
// the ADRP's register and this ADD's register are the same,
// then this is a pc-relative address calculation.
if (*type_ptr == LLVMDisassembler_ReferenceType_In_ARM64_ADDXri &&
m_adrp_insn.hasValue() && m_adrp_address == pc - 4 &&
(m_adrp_insn.getValue() & 0x1f) == ((value >> 5) & 0x1f)) {
uint32_t addxri_inst;
uint64_t adrp_imm, addxri_imm;
// Get immlo and immhi bits, OR them together to get the ADRP imm
// value.
adrp_imm = ((m_adrp_insn.getValue() & 0x00ffffe0) >> 3) |
((m_adrp_insn.getValue() >> 29) & 0x3);
// if high bit of immhi after right-shifting set, sign extend
if (adrp_imm & (1ULL << 20))
adrp_imm |= ~((1ULL << 21) - 1);
addxri_inst = value;
addxri_imm = (addxri_inst >> 10) & 0xfff;
// check if 'sh' bit is set, shift imm value up if so
// (this would make no sense, ADRP already gave us this part)
if ((addxri_inst >> (12 + 5 + 5)) & 1)
addxri_imm <<= 12;
value = (m_adrp_address & 0xfffffffffffff000LL) + (adrp_imm << 12) +
addxri_imm;
}
m_adrp_address = LLDB_INVALID_ADDRESS;
m_adrp_insn.reset();
}
if (m_inst->UsingFileAddress()) {
ModuleSP module_sp(m_inst->GetAddress().GetModule());
if (module_sp) {
module_sp->ResolveFileAddress(value, value_so_addr);
module_sp->ResolveFileAddress(pc, pc_so_addr);
}
} else if (target && !target->GetSectionLoadList().IsEmpty()) {
target->GetSectionLoadList().ResolveLoadAddress(value, value_so_addr);
target->GetSectionLoadList().ResolveLoadAddress(pc, pc_so_addr);
}
SymbolContext sym_ctx;
const SymbolContextItem resolve_scope =
eSymbolContextFunction | eSymbolContextSymbol;
if (pc_so_addr.IsValid() && pc_so_addr.GetModule()) {
pc_so_addr.GetModule()->ResolveSymbolContextForAddress(
pc_so_addr, resolve_scope, sym_ctx);
}
if (value_so_addr.IsValid() && value_so_addr.GetSection()) {
StreamString ss;
bool format_omitting_current_func_name = false;
if (sym_ctx.symbol || sym_ctx.function) {
AddressRange range;
if (sym_ctx.GetAddressRange(resolve_scope, 0, false, range) &&
range.GetBaseAddress().IsValid() &&
range.ContainsLoadAddress(value_so_addr, target)) {
format_omitting_current_func_name = true;
}
}
// If the "value" address (the target address we're symbolicating) is
// inside the same SymbolContext as the current instruction pc
// (pc_so_addr), don't print the full function name - just print it
// with DumpStyleNoFunctionName style, e.g. "<+36>".
if (format_omitting_current_func_name) {
value_so_addr.Dump(&ss, target, Address::DumpStyleNoFunctionName,
Address::DumpStyleSectionNameOffset);
} else {
value_so_addr.Dump(
&ss, target,
Address::DumpStyleResolvedDescriptionNoFunctionArguments,
Address::DumpStyleSectionNameOffset);
}
if (!ss.GetString().empty()) {
// If Address::Dump returned a multi-line description, most commonly
// seen when we have multiple levels of inlined functions at an
// address, only show the first line.
std::string str = std::string(ss.GetString());
size_t first_eol_char = str.find_first_of("\r\n");
if (first_eol_char != std::string::npos) {
str.erase(first_eol_char);
}
m_inst->AppendComment(str);
}
}
}
}
// TODO: llvm-objdump sets the type_ptr to the
// LLVMDisassembler_ReferenceType_Out_* values
// based on where value_so_addr is pointing, with
// Mach-O specific augmentations in MachODump.cpp. e.g.
// see what AArch64ExternalSymbolizer::tryAddingSymbolicOperand
// handles.
*type_ptr = LLVMDisassembler_ReferenceType_InOut_None;
*name = nullptr;
return nullptr;
}