add zero parameter to primitive allocation to improve codegen for calloc etc

This commit is contained in:
Daan Leijen 2022-04-19 18:32:35 -07:00
parent 9d69e3ed06
commit d69d4c861f
5 changed files with 77 additions and 63 deletions

View file

@ -106,7 +106,7 @@ void _mi_abandoned_await_readers(void);
// "page.c"
void* _mi_malloc_generic(mi_heap_t* heap, size_t size) mi_attr_noexcept mi_attr_malloc;
void* _mi_malloc_generic(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept mi_attr_malloc;
void _mi_page_retire(mi_page_t* page) mi_attr_noexcept; // free the page if there are no other pages with many free blocks
void _mi_page_unfull(mi_page_t* page);
@ -138,12 +138,11 @@ mi_msecs_t _mi_clock_end(mi_msecs_t start);
mi_msecs_t _mi_clock_start(void);
// "alloc.c"
void* _mi_page_malloc(mi_heap_t* heap, mi_page_t* page, size_t size) mi_attr_noexcept; // called from `_mi_malloc_generic`
void* _mi_page_malloc(mi_heap_t* heap, mi_page_t* page, size_t size, bool zero) mi_attr_noexcept; // called from `_mi_malloc_generic`
void* _mi_heap_malloc_zero(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept;
void* _mi_heap_realloc_zero(mi_heap_t* heap, void* p, size_t newsize, bool zero) mi_attr_noexcept;
mi_block_t* _mi_page_ptr_unalign(const mi_segment_t* segment, const mi_page_t* page, const void* p);
bool _mi_free_delayed_block(mi_block_t* block);
void _mi_block_zero_init(const mi_page_t* page, void* p, size_t size);
#if MI_DEBUG>1
bool _mi_page_is_valid(mi_page_t* page);
@ -267,8 +266,8 @@ static inline bool mi_mul_overflow(size_t count, size_t size, size_t* total) {
static inline bool mi_mul_overflow(size_t count, size_t size, size_t* total) {
#define MI_MUL_NO_OVERFLOW ((size_t)1 << (4*sizeof(size_t))) // sqrt(SIZE_MAX)
*total = count * size;
return ((size >= MI_MUL_NO_OVERFLOW || count >= MI_MUL_NO_OVERFLOW)
&& size > 0 && (SIZE_MAX / size) < count);
// note: gcc/clang optimize this to directly check the overflow flag
return ((size >= MI_MUL_NO_OVERFLOW || count >= MI_MUL_NO_OVERFLOW) && size > 0 && (SIZE_MAX / size) < count);
}
#endif
@ -279,7 +278,7 @@ static inline bool mi_count_size_overflow(size_t count, size_t size, size_t* tot
return false;
}
else if (mi_unlikely(mi_mul_overflow(count, size, total))) {
#if !defined(NDEBUG)
#if MI_DEBUG > 0
_mi_error_message(EOVERFLOW, "allocation request is too large (%zu * %zu bytes)\n", count, size);
#endif
*total = SIZE_MAX;
@ -925,7 +924,15 @@ static inline void _mi_memcpy(void* dst, const void* src, size_t n) {
__movsb((unsigned char*)dst, (const unsigned char*)src, n);
}
else {
memcpy(dst, src, n); // todo: use noinline?
memcpy(dst, src, n);
}
}
static inline void _mi_memzero(void* dst, size_t n) {
if (_mi_cpu_has_fsrm) {
__stosb((unsigned char*)dst, 0, n);
}
else {
memset(dst, 0, n);
}
}
#else
@ -933,6 +940,9 @@ static inline void _mi_memcpy(void* dst, const void* src, size_t n) {
static inline void _mi_memcpy(void* dst, const void* src, size_t n) {
memcpy(dst, src, n);
}
static inline void _mi_memzero(void* dst, size_t n) {
memset(dst, 0, n);
}
#endif
@ -950,12 +960,23 @@ static inline void _mi_memcpy_aligned(void* dst, const void* src, size_t n) {
const void* asrc = __builtin_assume_aligned(src, MI_INTPTR_SIZE);
_mi_memcpy(adst, asrc, n);
}
static inline void _mi_memzero_aligned(void* dst, size_t n) {
mi_assert_internal((uintptr_t)dst % MI_INTPTR_SIZE == 0);
void* adst = __builtin_assume_aligned(dst, MI_INTPTR_SIZE);
_mi_memzero(adst, n);
}
#else
// Default fallback on `_mi_memcpy`
static inline void _mi_memcpy_aligned(void* dst, const void* src, size_t n) {
mi_assert_internal(((uintptr_t)dst % MI_INTPTR_SIZE == 0) && ((uintptr_t)src % MI_INTPTR_SIZE == 0));
_mi_memcpy(dst, src, n);
}
static inline void _mi_memzero_aligned(void* dst, size_t n) {
mi_assert_internal((uintptr_t)dst % MI_INTPTR_SIZE == 0);
_mi_memzero(dst, n);
}
#endif