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556ace64e8
The existing memory arena impelmentation is moved into the pound::memory namespace to align with the pound::aarch64 namespace. Signed-off-by: Ronald Caesar <github43132@proton.me>
112 lines
3.3 KiB
C++
112 lines
3.3 KiB
C++
#ifndef POUND_ARENA_H
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#define POUND_ARENA_H
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#include <cstddef>
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#include <cstdint>
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#include <cstdlib>
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namespace pound::memory
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{
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#define POISON_PATTERN 0xAA
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/*
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* NAME
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* arena_t - memory management structure for efficient allocation and de-allocation.
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*
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* SYNOPSIS
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* typedef struct {
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* std::size_t capacity; Total number of bytes allocated.
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* std::size_t size; The current number of bytes consumed.
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* void* data; A pointer to the base address of the allocated memory buffer.
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* } arena_t;
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*
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* DESCRIPTION
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* The arena struct handles allocating and managing contiguous memory blocks.
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*
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* RATIONALE
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* A memory arena offers a safer alternative to malloc/realloc by
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* maintaining a single contiguous block eliminates heap fragmentation
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* that occurs with frequent small allocations.
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*/
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typedef struct
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{
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std::size_t capacity;
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std::size_t size;
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void* data;
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} arena_t;
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/*
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* NAME
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* arena_init - Initialize a memory arena with specified capacity.
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*
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* SYNOPSIS
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* memory::arena_t memory::arena_init(size_t capacity);
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*
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* DESCRIPTION
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* The function creates and returns a new memory arena instance with the
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* specified capacity.
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*
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* PARAMETERS
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* capacity - Size of the memory arena to allocate in bytes
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*
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* RETURN VALUE
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* Returns a valid memory::arena_t object on success. arena_t->data will be null on failure.
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*/
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memory::arena_t arena_init(size_t capacity);
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/*
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* NAME
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* arena_allocate - Allocate memory from a pre-initialized arena.
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*
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* SYNOPSIS
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* const void* memory::arena_allocate(memory::arena_t* arena, std::size_t size);
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*
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* DESCRIPTION
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* The function allocates size bytes from the specified arena. It assumes
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* the arena has sufficient capacity and returns a pointer to the allocated
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* memory region.
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*
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* RETURN VALUE
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* Returns a pointer to the first byte of the allocated memory. The returned
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* pointer is valid until the arena is reset or destroyed.
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*
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* NOTES
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* Requires arena_t to be initialized with arena_init() or similar.
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*/
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const void* arena_allocate(arena_t* arena, const std::size_t size);
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/*
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* NAME
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* arena_reset - Reset a memory arena's allocation size to zero.
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*
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* SYNOPSIS
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* void memory::arena_reset(memory::arena_t* arena);
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*
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* DESCRIPTION
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* The function resets the allocation size of a pre-initialized arena_t to zero.
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* This effectively "frees" all memory allocated from the arena without
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* deallocating the underlying buffer, allowing reuse of the capacity for
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* future allocations.
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*
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* NOTES
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* Resets arena->size to 0 while preserving arena->capacity.
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* Does not free the underlying memory buffer.
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* Useful for reusing arenas without reallocation.
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*/
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void arena_reset(arena_t* arena);
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/**
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* NAME
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* arena_free - Free the memory allocated by an arena
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*
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* SYNOPSIS
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* void memory::arena_free(memory::arena_t* arena);
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*
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* DESCRIPTION
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* The function releases the memory buffer associated with a arena_t and
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* resets its capacity and size to zero. This marks the arena as invalid for
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* future allocation unless reinitialized.
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*/
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void arena_free(memory::arena_t* arena);
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} // namespace pound::memory
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#endif //POUND_ARENA_H
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