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Merge branch 'dev' into dev-arena

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daan 2020-01-22 20:39:33 -08:00
commit e226ebcc97
20 changed files with 6123 additions and 216 deletions
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src/os.c
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@ -396,20 +396,20 @@ static void* mi_unix_mmap(void* addr, size_t size, size_t try_alignment, int pro
// On 64-bit systems, we can do efficient aligned allocation by using
// the 4TiB to 30TiB area to allocate them.
#if (MI_INTPTR_SIZE >= 8) && (defined(_WIN32) || (defined(MI_OS_USE_MMAP) && !defined(MAP_ALIGNED)))
static volatile _Atomic(intptr_t) aligned_base;
static volatile _Atomic(uintptr_t) aligned_base;
// Return a 4MiB aligned address that is probably available
static void* mi_os_get_aligned_hint(size_t try_alignment, size_t size) {
if (try_alignment == 0 || try_alignment > MI_SEGMENT_SIZE) return NULL;
if ((size%MI_SEGMENT_SIZE) != 0) return NULL;
intptr_t hint = mi_atomic_add(&aligned_base, size);
uintptr_t hint = mi_atomic_add(&aligned_base, size);
if (hint == 0 || hint > ((intptr_t)30<<40)) { // try to wrap around after 30TiB (area after 32TiB is used for huge OS pages)
intptr_t init = ((intptr_t)4 << 40); // start at 4TiB area
uintptr_t init = ((uintptr_t)4 << 40); // start at 4TiB area
#if (MI_SECURE>0 || MI_DEBUG==0) // security: randomize start of aligned allocations unless in debug mode
uintptr_t r = _mi_heap_random_next(mi_get_default_heap());
init = init + (MI_SEGMENT_SIZE * ((r>>17) & 0xFFFFF)); // (randomly 20 bits)*4MiB == 0 to 4TiB
#endif
mi_atomic_cas_strong(mi_atomic_cast(uintptr_t, &aligned_base), init, hint + size);
mi_atomic_cas_strong(&aligned_base, init, hint + size);
hint = mi_atomic_add(&aligned_base, size); // this may still give 0 or > 30TiB but that is ok, it is a hint after all
}
if (hint%try_alignment != 0) return NULL;