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merge from dev (bitmap split)

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daan 2020-09-08 10:33:30 -07:00
commit a948724340
18 changed files with 334 additions and 251 deletions
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104
include/mimalloc-internal.h
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@ -109,7 +109,6 @@ void _mi_page_reclaim(mi_heap_t* heap, mi_page_t* page); // callback fro
size_t _mi_bin_size(uint8_t bin); // for stats
uint8_t _mi_bin(size_t size); // for stats
uint8_t _mi_bsr(uintptr_t x); // bit-scan-right, used on BSD in "os.c"
// "heap.c"
void _mi_heap_destroy_pages(mi_heap_t* heap);
@ -859,5 +858,108 @@ static inline uintptr_t _mi_thread_id(void) mi_attr_noexcept {
}
#endif
// -----------------------------------------------------------------------
// Count bits: trailing or leading zeros (with MI_INTPTR_BITS on all zero)
// -----------------------------------------------------------------------
#if defined(__GNUC__)
#include <limits.h> // LONG_MAX
#define MI_HAVE_FAST_BITSCAN
static inline size_t mi_clz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
#if (INTPTR_MAX == LONG_MAX)
return __builtin_clzl(x);
#else
return __builtin_clzll(x);
#endif
}
static inline size_t mi_ctz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
#if (INTPTR_MAX == LONG_MAX)
return __builtin_ctzl(x);
#else
return __builtin_ctzll(x);
#endif
}
#elif defined(_MSC_VER)
#include <limits.h> // LONG_MAX
#define MI_HAVE_FAST_BITSCAN
static inline size_t mi_clz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
unsigned long idx;
#if (INTPTR_MAX == LONG_MAX)
_BitScanReverse(&idx, x);
#else
_BitScanReverse64(&idx, x);
#endif
return ((MI_INTPTR_BITS - 1) - idx);
}
static inline size_t mi_ctz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
unsigned long idx;
#if (INTPTR_MAX == LONG_MAX)
_BitScanForward(&idx, x);
#else
_BitScanForward64(&idx, x);
#endif
return idx;
}
#else
static inline size_t mi_ctz32(uint32_t x) {
// de Bruijn multiplication, see <http://supertech.csail.mit.edu/papers/debruijn.pdf>
static const unsigned char debruijn[32] = {
0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9
};
if (x==0) return 32;
return debruijn[((x & -(int32_t)x) * 0x077CB531UL) >> 27];
}
static inline size_t mi_clz32(uint32_t x) {
// de Bruijn multiplication, see <http://supertech.csail.mit.edu/papers/debruijn.pdf>
static const uint8_t debruijn[32] = {
31, 22, 30, 21, 18, 10, 29, 2, 20, 17, 15, 13, 9, 6, 28, 1,
23, 19, 11, 3, 16, 14, 7, 24, 12, 4, 8, 25, 5, 26, 27, 0
};
if (x==0) return 32;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
return debruijn[(uint32_t)(x * 0x07C4ACDDUL) >> 27];
}
static inline size_t mi_clz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
#if (MI_INTPTR_BITS <= 32)
return mi_clz32((uint32_t)x);
#else
size_t count = mi_clz32((uint32_t)(x >> 32));
if (count < 32) return count;
return (32 + mi_clz32((uint32_t)x));
#endif
}
static inline size_t mi_ctz(uintptr_t x) {
if (x==0) return MI_INTPTR_BITS;
#if (MI_INTPTR_BITS <= 32)
return mi_ctz32((uint32_t)x);
#else
size_t count = mi_ctz32((uint32_t)x);
if (count < 32) return count;
return (32 + mi_ctz32((uint32_t)(x>>32)));
#endif
}
#endif
// "bit scan reverse": Return index of the highest bit (or MI_INTPTR_BITS if `x` is zero)
static inline size_t mi_bsr(uintptr_t x) {
return (x==0 ? MI_INTPTR_BITS : MI_INTPTR_BITS - 1 - mi_clz(x));
}
#endif