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Include repetition in operation; simplify Instruction constructor.

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This commit is contained in:
Thomas Harte 2023-10-26 23:08:07 -04:00
parent 167b52c4ff
commit 8e35a56ff7
4 changed files with 172 additions and 124 deletions
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9
InstructionSets/x86/Decoder.cpp
View File

@ -33,8 +33,7 @@ std::pair<int, typename Decoder<model>::InstructionT> Decoder<model>::decode(con
/// Sets the operation and verifies that the current repetition, if any, is compatible, discarding it otherwise.
#define SetOperation(op) \
operation_ = op; \
repetition_ = supports(op, repetition_) ? repetition_ : Repetition::None
operation_ = rep_operation(op, repetition_);
/// Helper macro for those that follow.
#define SetOpSrcDestSize(op, src, dest, size) \
@ -1052,11 +1051,9 @@ std::pair<int, typename Decoder<model>::InstructionT> Decoder<model>::decode(con
lock_,
address_size_,
segment_override_,
repetition_,
operation_size_,
static_cast<typename InstructionT::DisplacementT>(displacement_),
static_cast<typename InstructionT::ImmediateT>(operand_),
consumed_
static_cast<typename InstructionT::ImmediateT>(operand_)
)
);
reset_parsing();
@ -1067,7 +1064,7 @@ std::pair<int, typename Decoder<model>::InstructionT> Decoder<model>::decode(con
if(consumed_ == max_instruction_length) {
std::pair<int, InstructionT> result;
if(max_instruction_length == 65536) {
result = std::make_pair(consumed_, InstructionT(Operation::NOP, consumed_));
result = std::make_pair(consumed_, InstructionT(Operation::NOP));
} else {
result = std::make_pair(consumed_, InstructionT());
}

125
InstructionSets/x86/Implementation/PerformImplementation.hpp
View File

@ -1379,17 +1379,17 @@ void pushf(MemoryT &memory, RegistersT &registers, Status &status) {
push<uint16_t>(value, memory, registers);
}
template <typename AddressT, typename InstructionT>
bool repetition_over(const InstructionT &instruction, AddressT &eCX) {
return instruction.repetition() != Repetition::None && !eCX;
template <typename AddressT, Repetition repetition>
bool repetition_over(const AddressT &eCX) {
return repetition != Repetition::None && !eCX;
}
template <typename AddressT, typename InstructionT, typename FlowControllerT>
void repeat_ene(const InstructionT &instruction, Status &status, AddressT &eCX, FlowControllerT &flow_controller) {
template <typename AddressT, Repetition repetition, typename FlowControllerT>
void repeat_ene(Status &status, AddressT &eCX, FlowControllerT &flow_controller) {
if(
instruction.repetition() == Repetition::None || // No repetition => stop.
repetition == Repetition::None || // No repetition => stop.
!(--eCX) || // [e]cx is zero after being decremented => stop.
(instruction.repetition() == Repetition::RepNE) == status.flag<Flag::Zero>()
(repetition == Repetition::RepNE) == status.flag<Flag::Zero>()
// repe and !zero, or repne and zero => stop.
) {
return;
@ -1397,20 +1397,20 @@ void repeat_ene(const InstructionT &instruction, Status &status, AddressT &eCX,
flow_controller.repeat_last();
}
template <typename AddressT, typename InstructionT, typename FlowControllerT>
void repeat(const InstructionT &instruction, AddressT &eCX, FlowControllerT &flow_controller) {
template <typename AddressT, Repetition repetition, typename FlowControllerT>
void repeat(AddressT &eCX, FlowControllerT &flow_controller) {
if(
instruction.repetition() == Repetition::None || // No repetition => stop.
!(--eCX) // [e]cx is zero after being decremented => stop.
repetition == Repetition::None || // No repetition => stop.
!(--eCX) // [e]cx is zero after being decremented => stop.
) {
return;
}
flow_controller.repeat_last();
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename FlowControllerT>
template <typename IntT, typename AddressT, Repetition repetition, typename InstructionT, typename MemoryT, typename FlowControllerT>
void cmps(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, AddressT &eDI, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
@ -1424,12 +1424,12 @@ void cmps(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, Address
Primitive::sub<false, false>(lhs, rhs, status);
repeat_ene<AddressT>(instruction, status, eCX, flow_controller);
repeat_ene<AddressT, repetition>(status, eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename FlowControllerT>
void scas(const InstructionT &instruction, AddressT &eCX, AddressT &eDI, IntT &eAX, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
template <typename IntT, typename AddressT, Repetition repetition, typename MemoryT, typename FlowControllerT>
void scas(AddressT &eCX, AddressT &eDI, IntT &eAX, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
@ -1438,12 +1438,12 @@ void scas(const InstructionT &instruction, AddressT &eCX, AddressT &eDI, IntT &e
Primitive::sub<false, false>(eAX, rhs, status);
repeat_ene<AddressT>(instruction, status, eCX, flow_controller);
repeat_ene<AddressT, repetition>(status, eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename FlowControllerT>
template <typename IntT, typename AddressT, Repetition repetition, typename InstructionT, typename MemoryT, typename FlowControllerT>
void lods(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, IntT &eAX, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
@ -1453,12 +1453,12 @@ void lods(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, IntT &e
eAX = memory.template access<IntT>(source_segment, eSI);
eSI += status.direction<AddressT>() * sizeof(IntT);
repeat<AddressT>(instruction, eCX, flow_controller);
repeat<AddressT, repetition>(eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename FlowControllerT>
template <typename IntT, typename AddressT, Repetition repetition, typename InstructionT, typename MemoryT, typename FlowControllerT>
void movs(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, AddressT &eDI, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
@ -1470,24 +1470,24 @@ void movs(const InstructionT &instruction, AddressT &eCX, AddressT &eSI, Address
eSI += status.direction<AddressT>() * sizeof(IntT);
eDI += status.direction<AddressT>() * sizeof(IntT);
repeat<AddressT>(instruction, eCX, flow_controller);
repeat<AddressT, repetition>(eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename FlowControllerT>
void stos(const InstructionT &instruction, AddressT &eCX, AddressT &eDI, IntT &eAX, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
template <typename IntT, typename AddressT, Repetition repetition, typename MemoryT, typename FlowControllerT>
void stos(AddressT &eCX, AddressT &eDI, IntT &eAX, MemoryT &memory, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
memory.template access<IntT>(Source::ES, eDI) = eAX;
eDI += status.direction<AddressT>() * sizeof(IntT);
repeat<AddressT>(instruction, eCX, flow_controller);
repeat<AddressT, repetition>(eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename IOT, typename FlowControllerT>
template <typename IntT, typename AddressT, Repetition repetition, typename InstructionT, typename MemoryT, typename IOT, typename FlowControllerT>
void outs(const InstructionT &instruction, AddressT &eCX, uint16_t port, AddressT &eSI, MemoryT &memory, IOT &io, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
@ -1496,19 +1496,19 @@ void outs(const InstructionT &instruction, AddressT &eCX, uint16_t port, Address
io.template out<IntT>(port, memory.template access<IntT>(source_segment, eSI));
eSI += status.direction<AddressT>() * sizeof(IntT);
repeat<AddressT>(instruction, eCX, flow_controller);
repeat<AddressT, repetition>(eCX, flow_controller);
}
template <typename IntT, typename AddressT, typename InstructionT, typename MemoryT, typename IOT, typename FlowControllerT>
void ins(const InstructionT &instruction, AddressT &eCX, uint16_t port, AddressT &eDI, MemoryT &memory, IOT &io, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT>(instruction, eCX)) {
template <typename IntT, typename AddressT, Repetition repetition, typename MemoryT, typename IOT, typename FlowControllerT>
void ins(AddressT &eCX, uint16_t port, AddressT &eDI, MemoryT &memory, IOT &io, Status &status, FlowControllerT &flow_controller) {
if(repetition_over<AddressT, repetition>(eCX)) {
return;
}
memory.template access<IntT>(Source::ES, eDI) = io.template in<IntT>(port);
eDI += status.direction<AddressT>() * sizeof(IntT);
repeat<AddressT>(instruction, eCX, flow_controller);
repeat<AddressT, repetition>(eCX, flow_controller);
}
template <typename IntT, typename IOT>
@ -1774,25 +1774,58 @@ template <
case Operation::PUSHF: Primitive::pushf(memory, registers, status); break;
case Operation::CMPS:
Primitive::cmps<IntT, AddressT>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
Primitive::cmps<IntT, AddressT, Repetition::None>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::LODS:
Primitive::lods<IntT, AddressT>(instruction, eCX(), eSI(), pair_low(), memory, status, flow_controller);
case Operation::CMPS_REPE:
Primitive::cmps<IntT, AddressT, Repetition::RepE>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::MOVS:
Primitive::movs<IntT, AddressT>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::STOS:
Primitive::stos<IntT, AddressT>(instruction, eCX(), eDI(), pair_low(), memory, status, flow_controller);
case Operation::CMPS_REPNE:
Primitive::cmps<IntT, AddressT, Repetition::RepNE>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::SCAS:
Primitive::scas<IntT, AddressT>(instruction, eCX(), eDI(), pair_low(), memory, status, flow_controller);
Primitive::scas<IntT, AddressT, Repetition::None>(eCX(), eDI(), pair_low(), memory, status, flow_controller);
break;
case Operation::SCAS_REPE:
Primitive::scas<IntT, AddressT, Repetition::RepE>(eCX(), eDI(), pair_low(), memory, status, flow_controller);
break;
case Operation::SCAS_REPNE:
Primitive::scas<IntT, AddressT, Repetition::RepNE>(eCX(), eDI(), pair_low(), memory, status, flow_controller);
break;
case Operation::LODS:
Primitive::lods<IntT, AddressT, Repetition::None>(instruction, eCX(), eSI(), pair_low(), memory, status, flow_controller);
break;
case Operation::LODS_REP:
Primitive::lods<IntT, AddressT, Repetition::RepE>(instruction, eCX(), eSI(), pair_low(), memory, status, flow_controller);
break;
case Operation::MOVS:
Primitive::movs<IntT, AddressT, Repetition::None>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::MOVS_REP:
Primitive::movs<IntT, AddressT, Repetition::RepE>(instruction, eCX(), eSI(), eDI(), memory, status, flow_controller);
break;
case Operation::STOS:
Primitive::stos<IntT, AddressT, Repetition::None>(eCX(), eDI(), pair_low(), memory, status, flow_controller);
break;
case Operation::STOS_REP:
Primitive::stos<IntT, AddressT, Repetition::RepE>(eCX(), eDI(), pair_low(), memory, status, flow_controller);
break;
case Operation::OUTS:
Primitive::outs<IntT, AddressT>(instruction, eCX(), registers.dx(), eSI(), memory, io, status, flow_controller);
Primitive::outs<IntT, AddressT, Repetition::None>(instruction, eCX(), registers.dx(), eSI(), memory, io, status, flow_controller);
break;
case Operation::OUTS_REP:
Primitive::outs<IntT, AddressT, Repetition::RepE>(instruction, eCX(), registers.dx(), eSI(), memory, io, status, flow_controller);
break;
case Operation::INS:
Primitive::outs<IntT, AddressT>(instruction, eCX(), registers.dx(), eDI(), memory, io, status, flow_controller);
Primitive::ins<IntT, AddressT, Repetition::None>(eCX(), registers.dx(), eDI(), memory, io, status, flow_controller);
break;
case Operation::INS_REP:
Primitive::ins<IntT, AddressT, Repetition::RepE>(eCX(), registers.dx(), eDI(), memory, io, status, flow_controller);
break;
}

80
InstructionSets/x86/Instruction.cpp
View File

@ -160,22 +160,54 @@ std::string InstructionSet::x86::to_string(Operation operation, DataSize size, M
constexpr char sizes[][6] = { "cmpsb", "cmpsw", "cmpsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::LODS: {
constexpr char sizes[][6] = { "lodsb", "lodsw", "lodsd", "?" };
case Operation::CMPS_REPE: {
constexpr char sizes[][11] = { "repe cmpsb", "repe cmpsw", "repe cmpsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::MOVS: {
constexpr char sizes[][6] = { "movsb", "movsw", "movsd", "?" };
case Operation::CMPS_REPNE: {
constexpr char sizes[][12] = { "repne cmpsb", "repne cmpsw", "repne cmpsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::SCAS: {
constexpr char sizes[][6] = { "scasb", "scasw", "scasd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::SCAS_REPE: {
constexpr char sizes[][11] = { "repe scasb", "repe scasw", "repe scasd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::SCAS_REPNE: {
constexpr char sizes[][12] = { "repne scasb", "repne scasw", "repne scasd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::LODS: {
constexpr char sizes[][6] = { "lodsb", "lodsw", "lodsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::LODS_REP: {
constexpr char sizes[][10] = { "rep lodsb", "rep lodsw", "rep lodsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::MOVS: {
constexpr char sizes[][6] = { "movsb", "movsw", "movsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::MOVS_REP: {
constexpr char sizes[][10] = { "rep movsb", "rep movsw", "rep movsd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::STOS: {
constexpr char sizes[][6] = { "stosb", "stosw", "stosd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::STOS_REP: {
constexpr char sizes[][10] = { "rep stosb", "rep stosw", "rep stosd", "?" };
return sizes[static_cast<int>(size)];
}
case Operation::LOOP: return "loop";
case Operation::LOOPE: return "loope";
@ -445,10 +477,21 @@ std::string InstructionSet::x86::to_string(
default: break;
case Operation::CMPS:
case Operation::CMPS_REPE:
case Operation::CMPS_REPNE:
case Operation::SCAS:
case Operation::SCAS_REPE:
case Operation::SCAS_REPNE:
case Operation::STOS:
case Operation::STOS_REP:
case Operation::LODS:
case Operation::LODS_REP:
case Operation::MOVS:
case Operation::MOVS_REP:
case Operation::INS:
case Operation::INS_REP:
case Operation::OUTS:
case Operation::OUTS_REP:
switch(instruction.second.segment_override()) {
default: break;
case Source::ES: operation += "es "; break;
@ -461,35 +504,6 @@ std::string InstructionSet::x86::to_string(
break;
}
// Add a repetition prefix; it'll be one of 'rep', 'repe' or 'repne'.
switch(instruction.second.repetition()) {
case Repetition::None: break;
case Repetition::RepE:
switch(instruction.second.operation) {
case Operation::CMPS:
case Operation::SCAS:
operation += "repe ";
break;
default:
operation += "rep ";
break;
}
break;
case Repetition::RepNE:
switch(instruction.second.operation) {
case Operation::CMPS:
case Operation::SCAS:
operation += "repne ";
break;
default:
operation += "rep ";
break;
}
break;
}
// Add operation itself.
operation += to_string(instruction.second.operation, instruction.second.operation_size(), model);
operation += " ";

82
InstructionSets/x86/Instruction.hpp
View File

@ -128,16 +128,23 @@ enum class Operation: uint8_t {
/// Computes the effective address of the source and loads it into the destination.
LEA,
/// Compare [bytes or words, per operation size]; source and destination implied to be DS:[SI] and ES:[DI].
CMPS,
/// Load string; reads from DS:SI into AL or AX, subject to segment override.
LODS,
/// Move string; moves a byte or word from DS:SI to ES:DI. If a segment override is provided, it overrides the the source.
MOVS,
/// Scan string; reads a byte or word from DS:SI and compares it to AL or AX.
SCAS,
MOVS_REP,
/// Load string; reads from DS:SI into AL or AX, subject to segment override.
LODS,
LODS_REP,
/// Store string; store AL or AX to ES:DI.
STOS,
STOS_REP,
/// Compare [bytes or words, per operation size]; source and destination implied to be DS:[SI] and ES:[DI].
CMPS,
CMPS_REPE,
CMPS_REPNE,
/// Scan string; reads a byte or word from DS:SI and compares it to AL or AX.
SCAS,
SCAS_REPE,
SCAS_REPNE,
// Perform a possibly-conditional loop, decrementing CX. See the displacement.
LOOP, LOOPE, LOOPNE,
@ -246,9 +253,11 @@ enum class Operation: uint8_t {
/// ES:[e]DI and incrementing or decrementing [e]DI as per the
/// current EFLAGS DF flag.
INS,
INS_REP,
/// Outputs a byte, word or double word from ES:[e]DI to the port specified by DX,
/// incrementing or decrementing [e]DI as per the current EFLAGS DF flag.
OUTS,
OUTS_REP,
/// Pushes all general purpose registers to the stack, in the order:
/// AX, CX, DX, BX, [original] SP, BP, SI, DI.
@ -465,31 +474,39 @@ enum class Repetition: uint8_t {
};
/// @returns @c true if @c operation supports repetition mode @c repetition; @c false otherwise.
constexpr bool supports(Operation operation, [[maybe_unused]] Repetition repetition) {
constexpr Operation rep_operation(Operation operation, Repetition repetition) {
switch(operation) {
default: return false;
default: return operation;
case Operation::Invalid: // Retain context here; it's used as an intermediate
// state sometimes.
case Operation::INS:
return repetition != Repetition::None ? Operation::INS_REP : Operation::INS;
case Operation::OUTS:
case Operation::CMPS:
return repetition != Repetition::None ? Operation::OUTS_REP : Operation::OUTS;
case Operation::LODS:
return repetition != Repetition::None ? Operation::LODS_REP : Operation::LODS;
case Operation::MOVS:
case Operation::SCAS:
return repetition != Repetition::None ? Operation::MOVS_REP : Operation::MOVS;
case Operation::STOS:
return true;
return repetition != Repetition::None ? Operation::STOS_REP : Operation::STOS;
// TODO: my new understanding is that the 8086 and 8088 recognise rep and repne on
// IDIV — and possibly DIV — as a quirk, affecting the outcome (possibly negativing the result?).
// So the test below should be a function of model, if I come to a conclusion about whether I'm
// going for fidelity to the instruction set as generally implemented, or to Intel's specific implementation.
// case Operation::IDIV:
// return repetition == Repetition::RepNE;
case Operation::CMPS:
switch(repetition) {
default:
case Repetition::None: return Operation::CMPS;
case Repetition::RepE: return Operation::CMPS_REPE;
case Repetition::RepNE: return Operation::CMPS_REPNE;
}
case Operation::SCAS:
switch(repetition) {
default:
case Repetition::None: return Operation::SCAS;
case Repetition::RepE: return Operation::SCAS_REPE;
case Repetition::RepNE: return Operation::SCAS_REPNE;
}
}
}
/// Provides a 32-bit-style scale, index and base; to produce the address this represents,
/// calcluate base() + (index() << scale()).
///
@ -790,11 +807,6 @@ template<bool is_32bit> class Instruction {
);
}
Repetition repetition() const {
if(!has_length_extension()) return Repetition::None;
return Repetition((length_extension() >> 4) & 3);
}
/// @returns The data size of this operation — e.g. `MOV AX, BX` has a data size of `::Word` but `MOV EAX, EBX` has a data size of
/// `::DWord`. This value is guaranteed never to be `DataSize::None` even for operations such as `CLI` that don't have operands and operate
/// on data that is not a byte, word or double word.
@ -802,12 +814,6 @@ template<bool is_32bit> class Instruction {
return DataSize(source_data_dest_sib_ >> 14);
}
// int length() const {
// const int short_length = (source_data_dest_sib_ >> 10) & 15;
// if(short_length) return short_length;
// return length_extension() >> 6;
// }
ImmediateT operand() const {
const ImmediateT ops[] = {0, operand_extension()};
return ops[has_operand()];
@ -825,8 +831,8 @@ template<bool is_32bit> class Instruction {
}
constexpr Instruction() noexcept {}
constexpr Instruction(Operation operation, int length) noexcept :
Instruction(operation, Source::None, Source::None, ScaleIndexBase(), false, AddressSize::b16, Source::None, Repetition::None, DataSize::None, 0, 0, length) {}
constexpr Instruction(Operation operation) noexcept :
Instruction(operation, Source::None, Source::None, ScaleIndexBase(), false, AddressSize::b16, Source::None, DataSize::None, 0, 0) {}
constexpr Instruction(
Operation operation,
Source source,
@ -835,11 +841,9 @@ template<bool is_32bit> class Instruction {
bool lock,
AddressSize address_size,
Source segment_override,
Repetition repetition,
DataSize data_size,
DisplacementT displacement,
ImmediateT operand,
int length) noexcept :
ImmediateT operand) noexcept :
operation(operation),
mem_exts_source_(uint8_t(
(int(address_size) << 7) |
@ -851,8 +855,8 @@ template<bool is_32bit> class Instruction {
source_data_dest_sib_(uint16_t(
(int(data_size) << 14) |
((
(lock || (segment_override != Source::None) || (length > 15) || (repetition != Repetition::None))
) ? 0 : (length << 10)) |
(lock || (segment_override != Source::None))
) ? 0 : (1 << 10)) |
((uint8_t(sib) & 0xf8) << 2) |
int(destination) |
(destination == Source::Indirect ? (uint8_t(sib) & 7) : 0)
@ -871,7 +875,7 @@ template<bool is_32bit> class Instruction {
}
if(has_length_extension()) {
extensions_[extension] = ImmediateT(
(length << 6) | (int(repetition) << 4) | ((int(segment_override) & 7) << 1) | int(lock)
((int(segment_override) & 7) << 1) | int(lock)
);
++extension;
}