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-rw-r--r--dom/canvas/MurmurHash3.cpp415
1 files changed, 415 insertions, 0 deletions
diff --git a/dom/canvas/MurmurHash3.cpp b/dom/canvas/MurmurHash3.cpp
new file mode 100644
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+++ b/dom/canvas/MurmurHash3.cpp
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+//-----------------------------------------------------------------------------
+// MurmurHash3 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+
+// Note - The x86 and x64 versions do _not_ produce the same results, as the
+// algorithms are optimized for their respective platforms. You can still
+// compile and run any of them on any platform, but your performance with the
+// non-native version will be less than optimal.
+
+#include "MurmurHash3.h"
+
+namespace {
+
+//-----------------------------------------------------------------------------
+// Platform-specific functions and macros
+
+// Microsoft Visual Studio
+
+#if defined(_MSC_VER)
+
+# define FORCE_INLINE __forceinline
+
+# define ROTL32(x, y) _rotl(x, y)
+# define ROTL64(x, y) _rotl64(x, y)
+
+# define BIG_CONSTANT(x) (x)
+
+// Other compilers
+
+#else // defined(_MSC_VER)
+
+// We can't do always_inline, becasue -Werror -Wattribute will trigger
+// a "might not be able to inline" warning.
+// #define FORCE_INLINE __attribute__((always_inline))
+# define FORCE_INLINE inline
+
+inline uint32_t rotl32(uint32_t x, int8_t r) {
+ return (x << r) | (x >> (32 - r));
+}
+
+inline uint64_t rotl64(uint64_t x, int8_t r) {
+ return (x << r) | (x >> (64 - r));
+}
+
+# define ROTL32(x, y) rotl32(x, y)
+# define ROTL64(x, y) rotl64(x, y)
+
+# define BIG_CONSTANT(x) (x##LLU)
+
+#endif // !defined(_MSC_VER)
+
+//-----------------------------------------------------------------------------
+// Block read - if your platform needs to do endian-swapping or can only
+// handle aligned reads, do the conversion here
+
+FORCE_INLINE uint32_t getblock(const uint32_t* p, int i) { return p[i]; }
+
+FORCE_INLINE uint64_t getblock(const uint64_t* p, int i) { return p[i]; }
+
+//-----------------------------------------------------------------------------
+// Finalization mix - force all bits of a hash block to avalanche
+
+FORCE_INLINE uint32_t fmix(uint32_t h) {
+ h ^= h >> 16;
+ h *= 0x85ebca6b;
+ h ^= h >> 13;
+ h *= 0xc2b2ae35;
+ h ^= h >> 16;
+
+ return h;
+}
+
+//----------
+
+FORCE_INLINE uint64_t fmix(uint64_t k) {
+ k ^= k >> 33;
+ k *= BIG_CONSTANT(0xff51afd7ed558ccd);
+ k ^= k >> 33;
+ k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);
+ k ^= k >> 33;
+
+ return k;
+}
+
+} // unnamed namespace
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x86_32(const void* key, int len, uint32_t seed, void* out) {
+ 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;
+
+ //----------
+ // body
+
+ const uint32_t* blocks = (const uint32_t*)(data + nblocks * 4);
+
+ for (int i = -nblocks; i; i++) {
+ uint32_t k1 = getblock(blocks, i);
+
+ k1 *= c1;
+ k1 = ROTL32(k1, 15);
+ k1 *= c2;
+
+ h1 ^= k1;
+ h1 = ROTL32(h1, 13);
+ h1 = h1 * 5 + 0xe6546b64;
+ }
+
+ //----------
+ // tail
+
+ const uint8_t* tail = (const uint8_t*)(data + nblocks * 4);
+
+ uint32_t k1 = 0;
+
+ switch (len & 3) {
+ case 3:
+ k1 ^= tail[2] << 16;
+ case 2:
+ k1 ^= tail[1] << 8;
+ case 1:
+ k1 ^= tail[0];
+ k1 *= c1;
+ k1 = ROTL32(k1, 15);
+ k1 *= c2;
+ h1 ^= k1;
+ }
+
+ //----------
+ // finalization
+
+ h1 ^= len;
+
+ h1 = fmix(h1);
+
+ *(uint32_t*)out = h1;
+}
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x86_128(const void* key, const int len, uint32_t seed,
+ void* out) {
+ const uint8_t* data = (const uint8_t*)key;
+ const int nblocks = len / 16;
+
+ uint32_t h1 = seed;
+ uint32_t h2 = seed;
+ uint32_t h3 = seed;
+ uint32_t h4 = seed;
+
+ const uint32_t c1 = 0x239b961b;
+ const uint32_t c2 = 0xab0e9789;
+ const uint32_t c3 = 0x38b34ae5;
+ const uint32_t c4 = 0xa1e38b93;
+
+ //----------
+ // body
+
+ const uint32_t* blocks = (const uint32_t*)(data + nblocks * 16);
+
+ for (int i = -nblocks; i; i++) {
+ uint32_t k1 = getblock(blocks, i * 4 + 0);
+ uint32_t k2 = getblock(blocks, i * 4 + 1);
+ uint32_t k3 = getblock(blocks, i * 4 + 2);
+ uint32_t k4 = getblock(blocks, i * 4 + 3);
+
+ k1 *= c1;
+ k1 = ROTL32(k1, 15);
+ k1 *= c2;
+ h1 ^= k1;
+
+ h1 = ROTL32(h1, 19);
+ h1 += h2;
+ h1 = h1 * 5 + 0x561ccd1b;
+
+ k2 *= c2;
+ k2 = ROTL32(k2, 16);
+ k2 *= c3;
+ h2 ^= k2;
+
+ h2 = ROTL32(h2, 17);
+ h2 += h3;
+ h2 = h2 * 5 + 0x0bcaa747;
+
+ k3 *= c3;
+ k3 = ROTL32(k3, 17);
+ k3 *= c4;
+ h3 ^= k3;
+
+ h3 = ROTL32(h3, 15);
+ h3 += h4;
+ h3 = h3 * 5 + 0x96cd1c35;
+
+ k4 *= c4;
+ k4 = ROTL32(k4, 18);
+ k4 *= c1;
+ h4 ^= k4;
+
+ h4 = ROTL32(h4, 13);
+ h4 += h1;
+ h4 = h4 * 5 + 0x32ac3b17;
+ }
+
+ //----------
+ // tail
+
+ const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);
+
+ uint32_t k1 = 0;
+ uint32_t k2 = 0;
+ uint32_t k3 = 0;
+ uint32_t k4 = 0;
+
+ switch (len & 15) {
+ case 15:
+ k4 ^= tail[14] << 16;
+ case 14:
+ k4 ^= tail[13] << 8;
+ case 13:
+ k4 ^= tail[12] << 0;
+ k4 *= c4;
+ k4 = ROTL32(k4, 18);
+ k4 *= c1;
+ h4 ^= k4;
+
+ case 12:
+ k3 ^= tail[11] << 24;
+ case 11:
+ k3 ^= tail[10] << 16;
+ case 10:
+ k3 ^= tail[9] << 8;
+ case 9:
+ k3 ^= tail[8] << 0;
+ k3 *= c3;
+ k3 = ROTL32(k3, 17);
+ k3 *= c4;
+ h3 ^= k3;
+
+ case 8:
+ k2 ^= tail[7] << 24;
+ case 7:
+ k2 ^= tail[6] << 16;
+ case 6:
+ k2 ^= tail[5] << 8;
+ case 5:
+ k2 ^= tail[4] << 0;
+ k2 *= c2;
+ k2 = ROTL32(k2, 16);
+ k2 *= c3;
+ h2 ^= k2;
+
+ case 4:
+ k1 ^= tail[3] << 24;
+ case 3:
+ k1 ^= tail[2] << 16;
+ case 2:
+ k1 ^= tail[1] << 8;
+ case 1:
+ k1 ^= tail[0] << 0;
+ k1 *= c1;
+ k1 = ROTL32(k1, 15);
+ k1 *= c2;
+ h1 ^= k1;
+ }
+
+ //----------
+ // finalization
+
+ h1 ^= len;
+ h2 ^= len;
+ h3 ^= len;
+ h4 ^= len;
+
+ h1 += h2;
+ h1 += h3;
+ h1 += h4;
+ h2 += h1;
+ h3 += h1;
+ h4 += h1;
+
+ h1 = fmix(h1);
+ h2 = fmix(h2);
+ h3 = fmix(h3);
+ h4 = fmix(h4);
+
+ h1 += h2;
+ h1 += h3;
+ h1 += h4;
+ h2 += h1;
+ h3 += h1;
+ h4 += h1;
+
+ ((uint32_t*)out)[0] = h1;
+ ((uint32_t*)out)[1] = h2;
+ ((uint32_t*)out)[2] = h3;
+ ((uint32_t*)out)[3] = h4;
+}
+
+//-----------------------------------------------------------------------------
+
+void MurmurHash3_x64_128(const void* key, const int len, const uint32_t seed,
+ void* out) {
+ const uint8_t* data = (const uint8_t*)key;
+ const int nblocks = len / 16;
+
+ uint64_t h1 = seed;
+ uint64_t h2 = seed;
+
+ const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
+ const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);
+
+ //----------
+ // body
+
+ const uint64_t* blocks = (const uint64_t*)(data);
+
+ for (int i = 0; i < nblocks; i++) {
+ uint64_t k1 = getblock(blocks, i * 2 + 0);
+ uint64_t k2 = getblock(blocks, i * 2 + 1);
+
+ k1 *= c1;
+ k1 = ROTL64(k1, 31);
+ k1 *= c2;
+ h1 ^= k1;
+
+ h1 = ROTL64(h1, 27);
+ h1 += h2;
+ h1 = h1 * 5 + 0x52dce729;
+
+ k2 *= c2;
+ k2 = ROTL64(k2, 33);
+ k2 *= c1;
+ h2 ^= k2;
+
+ h2 = ROTL64(h2, 31);
+ h2 += h1;
+ h2 = h2 * 5 + 0x38495ab5;
+ }
+
+ //----------
+ // tail
+
+ const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);
+
+ uint64_t k1 = 0;
+ uint64_t k2 = 0;
+
+ switch (len & 15) {
+ case 15:
+ k2 ^= uint64_t(tail[14]) << 48;
+ case 14:
+ k2 ^= uint64_t(tail[13]) << 40;
+ case 13:
+ k2 ^= uint64_t(tail[12]) << 32;
+ case 12:
+ k2 ^= uint64_t(tail[11]) << 24;
+ case 11:
+ k2 ^= uint64_t(tail[10]) << 16;
+ case 10:
+ k2 ^= uint64_t(tail[9]) << 8;
+ case 9:
+ k2 ^= uint64_t(tail[8]) << 0;
+ k2 *= c2;
+ k2 = ROTL64(k2, 33);
+ k2 *= c1;
+ h2 ^= k2;
+
+ case 8:
+ k1 ^= uint64_t(tail[7]) << 56;
+ case 7:
+ k1 ^= uint64_t(tail[6]) << 48;
+ case 6:
+ k1 ^= uint64_t(tail[5]) << 40;
+ case 5:
+ k1 ^= uint64_t(tail[4]) << 32;
+ case 4:
+ k1 ^= uint64_t(tail[3]) << 24;
+ case 3:
+ k1 ^= uint64_t(tail[2]) << 16;
+ case 2:
+ k1 ^= uint64_t(tail[1]) << 8;
+ case 1:
+ k1 ^= uint64_t(tail[0]) << 0;
+ k1 *= c1;
+ k1 = ROTL64(k1, 31);
+ k1 *= c2;
+ h1 ^= k1;
+ }
+
+ //----------
+ // finalization
+
+ h1 ^= len;
+ h2 ^= len;
+
+ h1 += h2;
+ h2 += h1;
+
+ h1 = fmix(h1);
+ h2 = fmix(h2);
+
+ h1 += h2;
+ h2 += h1;
+
+ ((uint64_t*)out)[0] = h1;
+ ((uint64_t*)out)[1] = h2;
+}
+
+//-----------------------------------------------------------------------------
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-28 15:49:10 +0000