diff options
Diffstat (limited to 'intern/cycles/util/util_murmurhash.cpp')
-rw-r--r-- | intern/cycles/util/util_murmurhash.cpp | 134 |
1 files changed, 67 insertions, 67 deletions
diff --git a/intern/cycles/util/util_murmurhash.cpp b/intern/cycles/util/util_murmurhash.cpp index 68df8fa1a84..5d728769fe9 100644 --- a/intern/cycles/util/util_murmurhash.cpp +++ b/intern/cycles/util/util_murmurhash.cpp @@ -27,15 +27,15 @@ #include "util/util_murmurhash.h" #if defined(_MSC_VER) -# define ROTL32(x,y) _rotl(x,y) -# define ROTL64(x,y) _rotl64(x,y) +# define ROTL32(x, y) _rotl(x, y) +# define ROTL64(x, y) _rotl64(x, y) # define BIG_CONSTANT(x) (x) #else ccl_device_inline uint32_t rotl32(uint32_t x, int8_t r) { - return (x << r) | (x >> (32 - r)); + return (x << r) | (x >> (32 - r)); } -# define ROTL32(x,y) rotl32(x,y) +# define ROTL32(x, y) rotl32(x, y) # define BIG_CONSTANT(x) (x##LLU) #endif @@ -45,82 +45,82 @@ CCL_NAMESPACE_BEGIN * handle aligned reads, do the conversion here. */ ccl_device_inline uint32_t mm_hash_getblock32(const uint32_t *p, int i) { - return p[i]; + return p[i]; } /* Finalization mix - force all bits of a hash block to avalanche */ -ccl_device_inline uint32_t mm_hash_fmix32 ( uint32_t h ) +ccl_device_inline uint32_t mm_hash_fmix32(uint32_t h) { - h ^= h >> 16; - h *= 0x85ebca6b; - h ^= h >> 13; - h *= 0xc2b2ae35; - h ^= h >> 16; - return h; + h ^= h >> 16; + h *= 0x85ebca6b; + h ^= h >> 13; + h *= 0xc2b2ae35; + h ^= h >> 16; + return h; } uint32_t util_murmur_hash3(const void *key, int len, uint32_t seed) { - const uint8_t * data = (const uint8_t*)key; - const int nblocks = len / 4; - - uint32_t h1 = seed; - - const uint32_t c1 = 0xcc9e2d51; - const uint32_t c2 = 0x1b873593; - - const uint32_t * blocks = (const uint32_t *)(data + nblocks*4); - - for(int i = -nblocks; i; i++) { - uint32_t k1 = mm_hash_getblock32(blocks,i); - - k1 *= c1; - k1 = ROTL32(k1,15); - k1 *= c2; - - h1 ^= k1; - h1 = ROTL32(h1,13); - h1 = h1 * 5 + 0xe6546b64; - } - - const uint8_t *tail = (const uint8_t*)(data + nblocks*4); - - uint32_t k1 = 0; - - switch(len & 3) { - case 3: - k1 ^= tail[2] << 16; - ATTR_FALLTHROUGH; - case 2: - k1 ^= tail[1] << 8; - ATTR_FALLTHROUGH; - case 1: - k1 ^= tail[0]; - k1 *= c1; - k1 = ROTL32(k1,15); - k1 *= c2; - h1 ^= k1; - } - - h1 ^= len; - h1 = mm_hash_fmix32(h1); - return h1; + const uint8_t *data = (const uint8_t *)key; + const int nblocks = len / 4; + + uint32_t h1 = seed; + + const uint32_t c1 = 0xcc9e2d51; + const uint32_t c2 = 0x1b873593; + + const uint32_t *blocks = (const uint32_t *)(data + nblocks * 4); + + for (int i = -nblocks; i; i++) { + uint32_t k1 = mm_hash_getblock32(blocks, i); + + k1 *= c1; + k1 = ROTL32(k1, 15); + k1 *= c2; + + h1 ^= k1; + h1 = ROTL32(h1, 13); + h1 = h1 * 5 + 0xe6546b64; + } + + const uint8_t *tail = (const uint8_t *)(data + nblocks * 4); + + uint32_t k1 = 0; + + switch (len & 3) { + case 3: + k1 ^= tail[2] << 16; + ATTR_FALLTHROUGH; + case 2: + k1 ^= tail[1] << 8; + ATTR_FALLTHROUGH; + case 1: + k1 ^= tail[0]; + k1 *= c1; + k1 = ROTL32(k1, 15); + k1 *= c2; + h1 ^= k1; + } + + h1 ^= len; + h1 = mm_hash_fmix32(h1); + return h1; } /* This is taken from the cryptomatte specification 1.0 */ float util_hash_to_float(uint32_t hash) { - uint32_t mantissa = hash & (( 1 << 23) - 1); - uint32_t exponent = (hash >> 23) & ((1 << 8) - 1); - exponent = max(exponent, (uint32_t) 1); - exponent = min(exponent, (uint32_t) 254); - exponent = exponent << 23; - uint32_t sign = (hash >> 31); - sign = sign << 31; - uint32_t float_bits = sign | exponent | mantissa; - float f; - memcpy(&f, &float_bits, sizeof(uint32_t)); - return f; + uint32_t mantissa = hash & ((1 << 23) - 1); + uint32_t exponent = (hash >> 23) & ((1 << 8) - 1); + exponent = max(exponent, (uint32_t)1); + exponent = min(exponent, (uint32_t)254); + exponent = exponent << 23; + uint32_t sign = (hash >> 31); + sign = sign << 31; + uint32_t float_bits = sign | exponent | mantissa; + float f; + memcpy(&f, &float_bits, sizeof(uint32_t)); + return f; } CCL_NAMESPACE_END |