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This commit is contained in:
Daan Leijen 2024-08-21 11:26:12 -07:00
parent 96f7cc4ef2
commit cc4dc1bb53
1 changed files with 10 additions and 2 deletions
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10
src/alloc.c
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@ -31,16 +31,20 @@ terms of the MIT license. A copy of the license can be found in the file
extern inline void* _mi_page_malloc_zero(mi_heap_t* heap, mi_page_t* page, size_t size, bool zero) mi_attr_noexcept
{
mi_assert_internal(page->block_size == 0 /* empty heap */ || mi_page_block_size(page) >= size);
// check the free list
mi_block_t* const block = page->free;
if mi_unlikely(block == NULL) {
return _mi_malloc_generic(heap, size, zero, 0);
}
mi_assert_internal(block != NULL && _mi_ptr_page(block) == page);
// pop from the free list
page->free = mi_block_next(page, block);
page->used++;
mi_assert_internal(page->free == NULL || _mi_ptr_page(page->free) == page);
mi_assert_internal(page->block_size < MI_MAX_ALIGN_SIZE || _mi_is_aligned(block, MI_MAX_ALIGN_SIZE));
#if MI_DEBUG>3
if (page->free_is_zero && size > sizeof(*block)) {
mi_assert_expensive(mi_mem_is_zero(block+1,size - sizeof(*block)));
@ -125,11 +129,11 @@ static inline bool mi_heap_malloc_small_use_guarded(size_t size);
static inline mi_decl_restrict void* mi_heap_malloc_small_zero(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept {
mi_assert(heap != NULL);
mi_assert(size <= MI_SMALL_SIZE_MAX);
#if MI_DEBUG
const uintptr_t tid = _mi_thread_id();
mi_assert(heap->thread_id == 0 || heap->thread_id == tid); // heaps are thread local
#endif
mi_assert(size <= MI_SMALL_SIZE_MAX);
#if (MI_PADDING || MI_DEBUG_GUARDED)
if (size == 0) { size = sizeof(void*); }
#endif
@ -137,6 +141,7 @@ static inline mi_decl_restrict void* mi_heap_malloc_small_zero(mi_heap_t* heap,
if (mi_heap_malloc_small_use_guarded(size)) { return mi_heap_malloc_guarded(heap, size, zero); }
#endif
// get page in constant time, and allocate from it
mi_page_t* page = _mi_heap_get_free_small_page(heap, size + MI_PADDING_SIZE);
void* const p = _mi_page_malloc_zero(heap, page, size + MI_PADDING_SIZE, zero);
mi_track_malloc(p,size,zero);
@ -166,6 +171,7 @@ mi_decl_nodiscard extern inline mi_decl_restrict void* mi_malloc_small(size_t si
// The main allocation function
extern inline void* _mi_heap_malloc_zero_ex(mi_heap_t* heap, size_t size, bool zero, size_t huge_alignment) mi_attr_noexcept {
// fast path for small objects
if mi_likely(size <= MI_SMALL_SIZE_MAX) {
mi_assert_internal(huge_alignment == 0);
return mi_heap_malloc_small_zero(heap, size, zero);
@ -174,10 +180,12 @@ extern inline void* _mi_heap_malloc_zero_ex(mi_heap_t* heap, size_t size, bool z
else if (mi_use_guarded(size,huge_alignment)) { return mi_heap_malloc_guarded(heap, size, zero); }
#endif
else {
// regular allocation
mi_assert(heap!=NULL);
mi_assert(heap->thread_id == 0 || heap->thread_id == _mi_thread_id()); // heaps are thread local
void* const p = _mi_malloc_generic(heap, size + MI_PADDING_SIZE, zero, huge_alignment); // note: size can overflow but it is detected in malloc_generic
mi_track_malloc(p,size,zero);
#if MI_STAT>1
if (p != NULL) {
if (!mi_heap_is_initialized(heap)) { heap = mi_prim_get_default_heap(); }