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fix fast divisor for 32-bit platforms

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This commit is contained in:
Daan 2024-10-22 06:08:56 -07:00
parent 46e9e7fdd0
commit 104e821709
1 changed files with 3 additions and 2 deletions
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5
src/heap.c
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@ -543,13 +543,14 @@ void _mi_heap_area_init(mi_heap_area_t* area, mi_page_t* page) {
static void mi_get_fast_divisor(size_t divisor, uint64_t* magic, size_t* shift) {
mi_assert_internal(divisor > 0 && divisor <= UINT32_MAX);
*shift = 64 - mi_clz(divisor - 1);
*shift = MI_INTPTR_BITS - mi_clz(divisor - 1);
*magic = ((((uint64_t)1 << 32) * (((uint64_t)1 << *shift) - divisor)) / divisor + 1);
}
static size_t mi_fast_divide(size_t n, uint64_t magic, size_t shift) {
mi_assert_internal(n <= UINT32_MAX);
return ((((uint64_t)n * magic) >> 32) + n) >> shift;
const uint64_t hi = ((uint64_t)n * magic) >> 32;
return (size_t)((hi + n) >> shift);
}
bool _mi_heap_area_visit_blocks(const mi_heap_area_t* area, mi_page_t* page, mi_block_visit_fun* visitor, void* arg) {