asmjit::BaseAssembler Class Reference

Base assembler.

This is a base class that provides interface used by architecture specific assembler implementations. Assembler doesn't hold any data, instead it's attached to CodeHolder, which provides all the data that Assembler needs and which can be altered by it.

Check out architecture specific assemblers for more details and examples:

Public Members

- Public Attributes inherited from asmjit::BaseEmitter

Public Types

- Public Types inherited from asmjit::BaseEmitter

Member Functions

Construction & Destruction
Code-Buffer Management
Section Management
Label Management
- Public Member Functions inherited from asmjit::BaseEmitter

Constructor & Destructor Documentation


Creates a new BaseAssembler instance.


Destroys the BaseAssembler instance.

Member Function Documentation

size_t BaseAssembler::bufferCapacity() constnoexcept

Returns the capacity of the current CodeBuffer.

size_t BaseAssembler::remainingSpace() constnoexcept

Returns the number of remaining bytes in the current CodeBuffer.

size_t BaseAssembler::offset() constnoexcept

Returns the current position in the CodeBuffer.

Error BaseAssembler::setOffset(size_t offset)

Sets the current position in the CodeBuffer to offset.

The offset cannot be greater than buffer size even if it's within the buffer's capacity.

uint8_t* BaseAssembler::bufferData() constnoexcept

Returns the start of the CodeBuffer in the current section.

uint8_t* BaseAssembler::bufferEnd() constnoexcept

Returns the end (first invalid byte) in the current section.

uint8_t* BaseAssembler::bufferPtr() constnoexcept

Returns the current pointer in the CodeBuffer in the current section.

Section* BaseAssembler::currentSection() constnoexcept

Returns the current section.

Label BaseAssembler::newLabel()override

Creates a new label.

Implements asmjit::BaseEmitter.

Label BaseAssembler::newNamedLabel(const char* name, size_t nameSize = SIZE_MAX, uint32_t type = Label::kTypeGlobal, uint32_t parentId = Globals::kInvalidId)override

Creates a new named label.

Implements asmjit::BaseEmitter.

Error BaseAssembler::bind(const Label& label)override

Binds the label to the current position of the current section.

Attempt to bind the same label multiple times will return an error.

Implements asmjit::BaseEmitter.

Error BaseAssembler::embed(const void* data, size_t dataSize)override

Embeds raw data into the CodeBuffer.

Implements asmjit::BaseEmitter.

Error BaseAssembler::embedDataArray(uint32_t typeId, const void* data, size_t itemCount, size_t repeatCount = 1)override

Embeds a typed data array.

This is the most flexible function for embedding data as it allows to:

  • Assign a typeId to the data, so the emitter knows the type of items stored in data. Binary data should use Type::kIdU8.
  • Repeat the given data repeatCount times, so the data can be used as a fill pattern for example, or as a pattern used by SIMD instructions.

Implements asmjit::BaseEmitter.

Error BaseAssembler::embedConstPool(const Label& label, const ConstPool& pool)override

Embeds a constant pool at the current offset by performing the following:

  1. Aligns by using kAlignData to the minimum pool alignment.
  2. Binds the ConstPool label so it's bound to an aligned location.
  3. Emits ConstPool content.

Implements asmjit::BaseEmitter.

Error BaseAssembler::embedLabel(const Label& label, size_t dataSize = 0)override

Embeds an absolute label address as data.

The dataSize is an optional argument that can be used to specify the size of the address data. If it's zero (default) the address size is deduced from the target architecture (either 4 or 8 bytes).

Implements asmjit::BaseEmitter.

Error BaseAssembler::embedLabelDelta(const Label& label, const Label& base, size_t dataSize = 0)override

Embeds a delta (distance) between the label and base calculating it as label - base.

This function was designed to make it easier to embed lookup tables where each index is a relative distance of two labels.

Implements asmjit::BaseEmitter.

Error BaseAssembler::comment(const char* data, size_t size = SIZE_MAX)override

Emits a comment stored in data with an optional size parameter.

Implements asmjit::BaseEmitter.

Error BaseAssembler::onAttach(CodeHolder* code)overridenoexcept

Called after the emitter was attached to CodeHolder.

Implements asmjit::BaseEmitter.

Reimplemented in asmjit::x86::Assembler.

Error BaseAssembler::onDetach(CodeHolder* code)overridenoexcept

Called after the emitter was detached from CodeHolder.

Implements asmjit::BaseEmitter.

Reimplemented in asmjit::x86::Assembler.

Member Data Documentation

Section* BaseAssembler::_section = nullptr

Current section where the assembling happens.

uint8_t* BaseAssembler::_bufferData = nullptr

Start of the CodeBuffer of the current section.

uint8_t* BaseAssembler::_bufferEnd = nullptr

End (first invalid byte) of the current section.

uint8_t* BaseAssembler::_bufferPtr = nullptr

Pointer in the CodeBuffer of the current section.