diff options
Diffstat (limited to 'include/mimalloc-internal.h')
| -rw-r--r-- | include/mimalloc-internal.h | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/include/mimalloc-internal.h b/include/mimalloc-internal.h index 99e4b5b..e648c1f 100644 --- a/include/mimalloc-internal.h +++ b/include/mimalloc-internal.h @@ -42,12 +42,17 @@ void _mi_trace_message(const char* fmt, ...); void _mi_options_init(void); void _mi_fatal_error(const char* fmt, ...) mi_attr_noreturn; -// "init.c" +// random.c +void _mi_random_init(mi_random_ctx_t* ctx); +void _mi_random_split(mi_random_ctx_t* ctx, mi_random_ctx_t* new_ctx); +uintptr_t _mi_random_next(mi_random_ctx_t* ctx); +uintptr_t _mi_heap_random_next(mi_heap_t* heap); +static inline uintptr_t _mi_random_shuffle(uintptr_t x); + +// init.c extern mi_stats_t _mi_stats_main; extern const mi_page_t _mi_page_empty; bool _mi_is_main_thread(void); -uintptr_t _mi_random_shuffle(uintptr_t x); -uintptr_t _mi_random_init(uintptr_t seed /* can be zero */); bool _mi_preloading(); // true while the C runtime is not ready // os.c @@ -100,7 +105,6 @@ uint8_t _mi_bsr(uintptr_t x); // bit-scan-right, used on BSD i // "heap.c" void _mi_heap_destroy_pages(mi_heap_t* heap); void _mi_heap_collect_abandon(mi_heap_t* heap); -uintptr_t _mi_heap_random(mi_heap_t* heap); void _mi_heap_set_default_direct(mi_heap_t* heap); // "stats.c" @@ -454,6 +458,29 @@ static inline void mi_block_set_next(const mi_page_t* page, mi_block_t* block, c #endif } +// ------------------------------------------------------------------- +// Fast "random" shuffle +// ------------------------------------------------------------------- + +static inline uintptr_t _mi_random_shuffle(uintptr_t x) { + mi_assert_internal(x!=0); +#if (MI_INTPTR_SIZE==8) + // by Sebastiano Vigna, see: <http://xoshiro.di.unimi.it/splitmix64.c> + x ^= x >> 30; + x *= 0xbf58476d1ce4e5b9UL; + x ^= x >> 27; + x *= 0x94d049bb133111ebUL; + x ^= x >> 31; +#elif (MI_INTPTR_SIZE==4) + // by Chris Wellons, see: <https://nullprogram.com/blog/2018/07/31/> + x ^= x >> 16; + x *= 0x7feb352dUL; + x ^= x >> 15; + x *= 0x846ca68bUL; + x ^= x >> 16; +#endif + return x; +} // ------------------------------------------------------------------- // Optimize numa node access for the common case (= one node) |