diff --git a/mem/include/arena/mem_arena.h b/mem/include/arena/mem_arena.h index 3389970..678426f 100644 --- a/mem/include/arena/mem_arena.h +++ b/mem/include/arena/mem_arena.h @@ -13,9 +13,6 @@ typedef struct growing_arena Arena; bool wapp_mem_arena_init(Arena **arena, u64 base_capacity); void *wapp_mem_arena_alloc(Arena *arena, u64 size); void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment); -void *wapp_mem_arena_realloc(Arena *arena, void *ptr, u64 size); -void *wapp_mem_arena_realloc_aligned(Arena *arena, void *ptr, u64 size, - u64 alignment); void wapp_mem_arena_clear(Arena *arena); void wapp_mem_arena_destroy(Arena **arena); diff --git a/mem/src/arena/mem_arena.c b/mem/src/arena/mem_arena.c index 4d2bba4..7c9655d 100644 --- a/mem/src/arena/mem_arena.c +++ b/mem/src/arena/mem_arena.c @@ -11,21 +11,8 @@ #define DEFAULT_ALIGNMENT (2 * sizeof(void *)) #endif /* ifndef DEFAULT_ALIGNMENT */ -#define HDR_MAGIC_BYTE_COUNT 8 -#define HDR_MAGIC \ - { 0x57, 0x41, 0x41, 0x52, 0x4e, 0x48, 0x44, 0x52 } -#define MAX_HDR_SEARCH_LENGTH 256 - #define ARENA_MINIMUM_CAPACITY 1024 -typedef struct arena_alloc_hdr ArenaAllocHDR; -struct arena_alloc_hdr { - u8 magic[HDR_MAGIC_BYTE_COUNT]; - u64 alloc_size; - u64 alignment; - u8 *alloc_start; -}; - typedef struct base_arena BaseArena; struct base_arena { u8 *buf; @@ -41,14 +28,11 @@ struct growing_arena { u64 initial_capacity; }; -internal BaseArena *find_arena_from_pointer(const Arena *arena, void *ptr); - internal bool base_arena_init(BaseArena *arena, u64 capacity); internal void *base_arena_alloc_aligned(BaseArena *arena, u64 size, u64 alignment); internal void base_arena_clear(BaseArena *arena); internal void base_arena_destroy(BaseArena *arena); -internal ArenaAllocHDR *find_alloc_header(BaseArena *arena, void *alloc_ptr); // PUBLIC API @@ -122,54 +106,6 @@ void *wapp_mem_arena_alloc_aligned(Arena *arena, u64 size, u64 alignment) { return output; } -void *wapp_mem_arena_realloc(Arena *arena, void *ptr, u64 size) { - return wapp_mem_arena_realloc_aligned(arena, ptr, size, DEFAULT_ALIGNMENT); -} - -void *wapp_mem_arena_realloc_aligned(Arena *arena, void *ptr, u64 size, - u64 alignment) { - if (!arena) { - return NULL; - } - - BaseArena *base_arena = find_arena_from_pointer(arena, ptr); - if (!base_arena) { - return NULL; - } - - ArenaAllocHDR *header = find_alloc_header(base_arena, ptr); - if (!header) { - return NULL; - } - - if (header->alloc_start + header->alloc_size == base_arena->offset) { - // Avoid allocating new pointer and copying memory if pointer is at the end - // of the arena - i64 diff = size - header->alloc_size; - - u8 *new_offset = base_arena->offset + diff; - - u8 *clear_start = diff < 0 ? new_offset : base_arena->offset; - memset(clear_start, 0, llabs(diff)); - - header->alloc_size = size; - base_arena->offset = new_offset; - - return header->alloc_start; - } - - void *new_alloc = wapp_mem_arena_alloc_aligned(arena, size, alignment); - if (!new_alloc) { - return NULL; - } - - u64 to_copy = size < header->alloc_size ? size : header->alloc_size; - - memcpy(new_alloc, ptr, to_copy); - - return new_alloc; -} - void wapp_mem_arena_clear(Arena *arena) { if (!arena) { return; @@ -235,30 +171,6 @@ void wapp_mem_arena_destroy(Arena **arena) { // INTERNAL FUNCTIONS -internal BaseArena *find_arena_from_pointer(const Arena *arena, void *ptr) { - if (!arena || !ptr) { - return NULL; - } - - // Ensure pointer is not out of bounds - u8 *alloc = (u8 *)ptr; - BaseArena *active = arena->active_arena; - - if (alloc > active->buf + arena->initial_capacity) { - return NULL; - } - - for (u64 i = 0; i < arena->count; ++i) { - if (alloc >= active->buf && alloc < active->buf + arena->initial_capacity) { - return (BaseArena *)active; - } - - active = active->prev; - } - - return NULL; -} - internal bool base_arena_init(BaseArena *arena, u64 capacity) { if (!arena || arena->buf || capacity == 0) { return false; @@ -285,22 +197,13 @@ internal void *base_arena_alloc_aligned(BaseArena *arena, u64 size, return NULL; } - u8 *start_offset = arena->offset; - u8 *alloc_start = arena->offset + sizeof(ArenaAllocHDR); + u8 *alloc_start = arena->offset; u8 *output = wapp_mem_util_align_forward((void *)alloc_start, alignment); if (output + size >= arena->buf + arena->capacity) { return NULL; } - ArenaAllocHDR *header = (ArenaAllocHDR *)start_offset; - *header = (ArenaAllocHDR){ - .magic = HDR_MAGIC, - .alloc_size = size, - .alignment = alignment, - .alloc_start = output, - }; - arena->offset = output + size; return (void *)output; @@ -328,33 +231,3 @@ internal void base_arena_destroy(BaseArena *arena) { arena->capacity = 0; arena->prev = arena->next = NULL; } - -internal ArenaAllocHDR *find_alloc_header(BaseArena *arena, void *alloc_ptr) { - persistent const u8 magic[HDR_MAGIC_BYTE_COUNT] = HDR_MAGIC; - - u8 *current = (u8 *)alloc_ptr; - - u8 *max_search_end = current - MAX_HDR_SEARCH_LENGTH; - u8 *arena_buf_start = arena->buf; - - u8 *search_end = - max_search_end > arena_buf_start ? max_search_end : arena_buf_start; - - bool match; - for (; current >= search_end; --current) { - match = true; - - for (u64 i = 0; i < HDR_MAGIC_BYTE_COUNT; ++i) { - if (current[i] != magic[i]) { - match = false; - break; - } - } - - if (match) { - return (ArenaAllocHDR *)current; - } - } - - return NULL; -}