asmjit::Operand_ Struct Reference

Inheritance diagram for asmjit::Operand_:

Base class representing an operand in AsmJit (non-default constructed version).

Contains no initialization code and can be used safely to define an array of operands that won't be initialized. This is a Operand base structure designed to be statically initialized, static const, or to be used by user code to define an array of operands without having them default initialized at construction time.

The key difference between Operand and Operand_ is:

Operand_ xArray[10];    // Not initialized, contains garbage.
Operand_ yArray[10] {}; // All operands initialized to none explicitly (zero initialized).
Operand  yArray[10];    // All operands initialized to none implicitly (zero initialized).

Public Members

Members

Signature _signature

uint32_t _baseId

uint32_t _data[2]

Public Types

Constants

enum DataIndex : uint32_t

enum VirtIdConstants : uint32_t

Types

typedef OperandSignature Signature

Member Functions

Construction & Destruction

void copyFrom(const Operand_& other) noexcept

void reset() noexcept

Overloaded Operators

constexpr bool operator==(const Operand_& other) const noexcept

constexpr bool operator!=(const Operand_& other) const noexcept

Cast

template<typename T>

T& as() noexcept

template<typename T>

const T& as() const noexcept

Equality

constexpr bool equals(const Operand_& other) const noexcept

Accessors

constexpr bool hasSignature(const Operand_& other) const noexcept

constexpr bool hasSignature(const Signature& other) const noexcept

constexpr Signature signature() const noexcept

void setSignature(const Signature& signature) noexcept

void setSignature(uint32_t signature) noexcept

constexpr OperandType opType() const noexcept

constexpr bool isNone() const noexcept

constexpr bool isReg() const noexcept

constexpr bool isRegList() const noexcept

constexpr bool isMem() const noexcept

constexpr bool isImm() const noexcept

constexpr bool isLabel() const noexcept

constexpr bool isPhysReg() const noexcept

constexpr bool isVirtReg() const noexcept

constexpr uint32_t id() const noexcept

constexpr bool isReg(RegType type) const noexcept

constexpr bool isReg(RegGroup regGroup) const noexcept

constexpr bool isReg(RegType regType, uint32_t regId) const noexcept

constexpr bool isReg(RegGroup regGroup, uint32_t regId) const noexcept

constexpr bool isGp() const noexcept

constexpr bool isGp32() const noexcept

constexpr bool isGp64() const noexcept

constexpr bool isVec() const noexcept

constexpr bool isVec8() const noexcept

constexpr bool isVec16() const noexcept

constexpr bool isVec32() const noexcept

constexpr bool isVec64() const noexcept

constexpr bool isVec128() const noexcept

constexpr bool isVec256() const noexcept

constexpr bool isVec512() const noexcept

constexpr bool isMask() const noexcept

constexpr bool isRegList(RegType type) const noexcept

constexpr bool isRegOrMem() const noexcept

constexpr bool isRegOrRegListOrMem() const noexcept

Accessors (X86 Specific)

constexpr uint32_t x86RmSize() const noexcept

Static Functions

static bool isVirtId(uint32_t id) noexcept

static uint32_t indexToVirtId(uint32_t id) noexcept

static uint32_t virtIdToIndex(uint32_t id) noexcept

Member Enumeration Documentation

Operand_::VirtIdConstants : uint32_tenum

Constants useful for VirtId <-> Index translation.

Constant	Description
kVirtIdMin	Minimum valid packed-id.
kVirtIdMax	Maximum valid packed-id, excludes Globals::kInvalidId.
kVirtIdCount	Count of valid packed-ids.

Member Function Documentation

bool Operand_::isVirtId(uint32_t id)staticnoexcept

Tests whether the given id is a valid virtual register id.

Since AsmJit supports both physical and virtual registers it must be able to distinguish between these two. The idea is that physical registers are always limited in size, so virtual identifiers start from kVirtIdMin and end at kVirtIdMax.

uint32_t Operand_::indexToVirtId(uint32_t id)staticnoexcept

Converts a real-id into a packed-id that can be stored in Operand.

uint32_t Operand_::virtIdToIndex(uint32_t id)staticnoexcept

Converts a packed-id back to real-id.

void Operand_::copyFrom(const Operand_& other)noexcept

Initializes the operand from other operand (used by operator overloads).

void Operand_::reset()noexcept

Resets the Operand to none.

None operand is defined the following way:

• Its signature is zero (OperandType::kNone, and the rest zero as well).
• Its id is 0.
• The reserved8_4 field is set to 0.
• The reserved12_4 field is set to zero.

In other words, reset operands have all members set to zero. Reset operand must match the Operand state right after its construction. Alternatively, if you have an array of operands, you can simply use memset().

using namespace asmjit;
 
Operand a;
Operand b;
assert(a == b);
 
b = x86::eax;
assert(a != b);
 
b.reset();
assert(a == b);
 
memset(&b, 0, sizeof(Operand));
assert(a == b);

bool Operand_::operator==(const Operand_& other) constconstexprconstexprnoexcept

Tests whether this operand is the same as other.

bool Operand_::operator!=(const Operand_& other) constconstexprconstexprnoexcept

Tests whether this operand is not the same as other.

template<typename T>

T& Operand_::as()noexcept[1/2]

Casts this operand to T type.

template<typename T>

const T& Operand_::as() constnoexcept[2/2]

Casts this operand to T type (const).

bool Operand_::equals(const Operand_& other) constconstexprconstexprnoexcept

Tests whether the operand is 100% equal to other operand.

Note

This basically performs a binary comparison, if aby bit is different the operands are not equal.

bool Operand_::hasSignature(const Operand_& other) constconstexprconstexprnoexcept[1/2]

Tests whether the operand's signature matches the signature of the other operand.

bool Operand_::hasSignature(const Signature& other) constconstexprconstexprnoexcept[2/2]

Tests whether the operand's signature matches the given signature sign.

Signature Operand_::signature() constconstexprconstexprnoexcept

Returns operand signature as unsigned 32-bit integer.

Signature is first 4 bytes of the operand data. It's used mostly for operand checking as it's much faster to check packed 4 bytes at once than having to check these bytes individually.

void Operand_::setSignature(const Signature& signature)noexcept[1/2]

Sets the operand signature, see signature().

Note

Improper use of setSignature() can lead to hard-to-debug errors.

void Operand_::setSignature(uint32_t signature)noexcept[2/2]

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

OperandType Operand_::opType() constconstexprconstexprnoexcept

Returns the type of the operand, see OpType.

bool Operand_::isNone() constconstexprconstexprnoexcept

Tests whether the operand is none (OperandType::kNone).

bool Operand_::isReg() constconstexprconstexprnoexcept[1/5]

Tests whether the operand is a register (OperandType::kReg).

bool Operand_::isRegList() constconstexprconstexprnoexcept[1/2]

Tests whether the operand is a register-list.

Note

Register-list is currently only used by 32-bit ARM architecture.

bool Operand_::isMem() constconstexprconstexprnoexcept

Tests whether the operand is a memory location (OperandType::kMem).

bool Operand_::isImm() constconstexprconstexprnoexcept

Tests whether the operand is an immediate (OperandType::kImm).

bool Operand_::isLabel() constconstexprconstexprnoexcept

Tests whether the operand is a label (OperandType::kLabel).

bool Operand_::isPhysReg() constconstexprconstexprnoexcept

Tests whether the operand is a physical register.

bool Operand_::isVirtReg() constconstexprconstexprnoexcept

Tests whether the operand is a virtual register.

uint32_t Operand_::id() constconstexprconstexprnoexcept

Returns the operand id.

The value returned should be interpreted accordingly to the operand type:

• None - Should be 0.
• Reg - Physical or virtual register id.
• Mem - Multiple meanings - BASE address (register or label id), or high value of a 64-bit absolute address.
• Imm - Should be 0.
• Label - Label id if it was created by using newLabel() or Globals::kInvalidId if the label is invalid or not initialized.

bool Operand_::isReg(RegType type) constconstexprconstexprnoexcept[2/5]

Tests whether the operand is a register matching the given register type.

bool Operand_::isReg(RegGroup regGroup) constconstexprconstexprnoexcept[3/5]

Tests whether the operand is a register of the provided register group regGroup.

bool Operand_::isReg(RegType regType, uint32_t regId) constconstexprconstexprnoexcept[4/5]

Tests whether the operand is register and of register type regType and regId.

bool Operand_::isReg(RegGroup regGroup, uint32_t regId) constconstexprconstexprnoexcept[5/5]

Tests whether the operand is register and of register group regGroup and regId.

bool Operand_::isGp() constconstexprconstexprnoexcept

Tests whether the register is a general purpose register (any size).

bool Operand_::isGp32() constconstexprconstexprnoexcept

Tests whether the register is a 32-bit general purpose register.

bool Operand_::isGp64() constconstexprconstexprnoexcept

Tests whether the register is a 64-bit general purpose register.

bool Operand_::isVec() constconstexprconstexprnoexcept

Tests whether the register is a vector register of any size.

bool Operand_::isVec8() constconstexprconstexprnoexcept

Tests whether the register is an 8-bit vector register or view (AArch64).

bool Operand_::isVec16() constconstexprconstexprnoexcept

Tests whether the register is a 16-bit vector register or view (AArch64).

bool Operand_::isVec32() constconstexprconstexprnoexcept

Tests whether the register is a 32-bit vector register or view (AArch32, AArch64).

bool Operand_::isVec64() constconstexprconstexprnoexcept

Tests whether the register is a 64-bit vector register or view (AArch32, AArch64).

bool Operand_::isVec128() constconstexprconstexprnoexcept

Tests whether the register is a 128-bit vector register or view (AArch32, AArch64, X86, X86_64).

bool Operand_::isVec256() constconstexprconstexprnoexcept

Tests whether the register is a 256-bit vector register or view (X86, X86_64).

bool Operand_::isVec512() constconstexprconstexprnoexcept

Tests whether the register is a 512-bit vector register or view (X86, X86_64).

bool Operand_::isMask() constconstexprconstexprnoexcept

Tests whether the register is a mask register of any size.

bool Operand_::isRegList(RegType type) constconstexprconstexprnoexcept[2/2]

Tests whether the operand is a register matching the given register type.

bool Operand_::isRegOrMem() constconstexprconstexprnoexcept

Tests whether the operand is a register or memory.

Note

This is useful on X86 and X86_64 architectures as many instructions support Reg/Mem operand combination. So if the user code works with just Operand, it's possible to check whether the operand is either a register or memory location with a single check.

bool Operand_::isRegOrRegListOrMem() constconstexprconstexprnoexcept

Tests whether the operand is a register, register-list, or memory.

Note

This is useful on 32-bit ARM architecture to check whether an operand references a register. It can be used in other architectures too, but it would work identically to isRegOrMem() as other architectures don't provide register lists.

uint32_t Operand_::x86RmSize() constconstexprconstexprnoexcept

Returns a size of a register or an X86 memory operand.

Remarks

At the moment only X86 and X86_64 memory operands have a size - other memory operands can use bits that represent size as an additional payload. This means that memory size is architecture specific and should be accessed via x86::Mem::size(). Sometimes when the user knows that the operand is either a register or memory operand this function can be helpful as it avoids casting, but it only works when it targets X86 and X86_64.

Member Data Documentation

Signature Operand_::_signature

Provides operand type and additional payload.

uint32_t Operand_::_baseId

Either base id as used by memory operand or any id as used by others.

uint32_t Operand_::_data[2]

Data specific to the operand type.

The reason we don't use union is that we have constexpr constructors that construct operands and other constexpr functions that return whether another Operand or something else. These cannot generally work with unions so we also cannot use union if we want to be standard compliant.