asmjit::ConstPool Class Reference

Constant pool.

Constant pool is designed to hold 1, 2, 4, 8, 16, 32, and 64 byte constants. It's not designed to hold constants having arbitrary length like strings and arrays.

Public Members

Members

Zone* _zone

Tree _tree[kIndexCount]

Gap* _gaps[kIndexCount]

Gap* _gapPool

size_t _size

size_t _alignment

size_t _minItemSize

Member Functions

ConstPool(const ConstPool& other) = delete

ConstPool& operator=(const ConstPool& other) = delete

Construction & Destruction

ConstPool(Zone* zone) noexcept

~ConstPool() noexcept

Reset

void reset(Zone* zone) noexcept

Accessors

bool empty() const noexcept

size_t size() const noexcept

size_t alignment() const noexcept

size_t minItemSize() const noexcept

Utilities

Error add(const void* data, size_t size, size_t& dstOffset) noexcept

void fill(void* dst) const noexcept

Constructor & Destructor Documentation

ConstPool::ConstPool(Zone* zone)explicitnoexcept

Creates a new constant pool that would use zone as a memory allocator.

ConstPool::~ConstPool()noexcept

Destroys this constant pool.

Member Function Documentation

void ConstPool::reset(Zone* zone)noexcept

Resets this constant pool and its allocator to zone.

bool ConstPool::empty() constnoexcept

Tests whether the constant-pool is empty.

size_t ConstPool::size() constnoexcept

Returns the size of the constant-pool in bytes.

size_t ConstPool::alignment() constnoexcept

Returns minimum alignment.

size_t ConstPool::minItemSize() constnoexcept

Returns the minimum size of all items added to the constant pool.

Error ConstPool::add(const void* data, size_t size, size_t& dstOffset)noexcept

Adds a constant to the constant pool.

The constant must have known size, which is 1, 2, 4, 8, 16 or 32 bytes. The constant is added to the pool only if it doesn't not exist, otherwise cached value is returned.

AsmJit is able to subdivide added constants, so for example if you add 8-byte constant 0x1122334455667788 it will create the following slots:

8-byte: 0x1122334455667788 4-byte: 0x11223344, 0x55667788

The reason is that when combining MMX/SSE/AVX code some patterns are used frequently. However, AsmJit is not able to reallocate a constant that has been already added. For example if you try to add 4-byte constant and then 8-byte constant having the same 4-byte pattern as the previous one, two independent slots will be used.

void ConstPool::fill(void* dst) constnoexcept

Fills the destination with the content of this constant pool.

Member Data Documentation

Zone* ConstPool::_zone

Zone allocator.

Tree ConstPool::_tree[kIndexCount]

Tree per size.

Gap* ConstPool::_gaps[kIndexCount]

Gaps per size.

Gap* ConstPool::_gapPool

Gaps pool.

size_t ConstPool::_size

Size of the pool (in bytes).

size_t ConstPool::_alignment

Required pool alignment.

size_t ConstPool::_minItemSize

Minimum item size in the pool.