mirror of
https://github.com/Lime3DS/Lime3DS.git
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651 lines
21 KiB
C++
651 lines
21 KiB
C++
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// Copyright (c) 2011 Google, Inc.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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//
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// CityHash, by Geoff Pike and Jyrki Alakuijala
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//
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// This file provides CityHash64() and related functions.
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//
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// It's probably possible to create even faster hash functions by
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// writing a program that systematically explores some of the space of
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// possible hash functions, by using SIMD instructions, or by
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// compromising on hash quality.
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#include <algorithm>
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#include <string.h> // for memcpy and memset
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#include "cityhash.h"
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#include "common/swap.h"
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// #include "config.h"
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#ifdef __GNUC__
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#define HAVE_BUILTIN_EXPECT 1
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#endif
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#ifdef COMMON_BIG_ENDIAN
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#define WORDS_BIGENDIAN 1
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#endif
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using namespace std;
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static uint64 UNALIGNED_LOAD64(const char* p) {
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uint64 result;
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memcpy(&result, p, sizeof(result));
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return result;
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}
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static uint32 UNALIGNED_LOAD32(const char* p) {
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uint32 result;
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memcpy(&result, p, sizeof(result));
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return result;
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}
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#ifdef _MSC_VER
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#include <stdlib.h>
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#define bswap_32(x) _byteswap_ulong(x)
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#define bswap_64(x) _byteswap_uint64(x)
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#elif defined(__APPLE__)
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// Mac OS X / Darwin features
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#include <libkern/OSByteOrder.h>
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#define bswap_32(x) OSSwapInt32(x)
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#define bswap_64(x) OSSwapInt64(x)
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#elif defined(__sun) || defined(sun)
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#include <sys/byteorder.h>
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#define bswap_32(x) BSWAP_32(x)
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#define bswap_64(x) BSWAP_64(x)
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#elif defined(__FreeBSD__)
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#include <sys/endian.h>
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#define bswap_32(x) bswap32(x)
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#define bswap_64(x) bswap64(x)
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#elif defined(__OpenBSD__)
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#include <sys/types.h>
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#define bswap_32(x) swap32(x)
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#define bswap_64(x) swap64(x)
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#elif defined(__NetBSD__)
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#include <machine/bswap.h>
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#include <sys/types.h>
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#if defined(__BSWAP_RENAME) && !defined(__bswap_32)
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#define bswap_32(x) bswap32(x)
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#define bswap_64(x) bswap64(x)
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#endif
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#else
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#include <byteswap.h>
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#endif
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#ifdef WORDS_BIGENDIAN
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#define uint32_in_expected_order(x) (bswap_32(x))
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#define uint64_in_expected_order(x) (bswap_64(x))
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#else
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#define uint32_in_expected_order(x) (x)
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#define uint64_in_expected_order(x) (x)
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#endif
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#if !defined(LIKELY)
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#if HAVE_BUILTIN_EXPECT
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#define LIKELY(x) (__builtin_expect(!!(x), 1))
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#else
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#define LIKELY(x) (x)
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#endif
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#endif
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static uint64 Fetch64(const char* p) {
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return uint64_in_expected_order(UNALIGNED_LOAD64(p));
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}
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static uint32 Fetch32(const char* p) {
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return uint32_in_expected_order(UNALIGNED_LOAD32(p));
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}
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// Some primes between 2^63 and 2^64 for various uses.
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static const uint64 k0 = 0xc3a5c85c97cb3127ULL;
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static const uint64 k1 = 0xb492b66fbe98f273ULL;
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static const uint64 k2 = 0x9ae16a3b2f90404fULL;
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// Magic numbers for 32-bit hashing. Copied from Murmur3.
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static const uint32 c1 = 0xcc9e2d51;
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static const uint32 c2 = 0x1b873593;
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// A 32-bit to 32-bit integer hash copied from Murmur3.
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static uint32 fmix(uint32 h) {
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h ^= h >> 16;
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h *= 0x85ebca6b;
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h ^= h >> 13;
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h *= 0xc2b2ae35;
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h ^= h >> 16;
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return h;
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}
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static uint32 Rotate32(uint32 val, int shift) {
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// Avoid shifting by 32: doing so yields an undefined result.
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return shift == 0 ? val : ((val >> shift) | (val << (32 - shift)));
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}
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#undef PERMUTE3
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#define PERMUTE3(a, b, c) \
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do { \
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std::swap(a, b); \
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std::swap(a, c); \
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} while (0)
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static uint32 Mur(uint32 a, uint32 h) {
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// Helper from Murmur3 for combining two 32-bit values.
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a *= c1;
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a = Rotate32(a, 17);
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a *= c2;
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h ^= a;
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h = Rotate32(h, 19);
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return h * 5 + 0xe6546b64;
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}
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static uint32 Hash32Len13to24(const char* s, size_t len) {
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uint32 a = Fetch32(s - 4 + (len >> 1));
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uint32 b = Fetch32(s + 4);
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uint32 c = Fetch32(s + len - 8);
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uint32 d = Fetch32(s + (len >> 1));
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uint32 e = Fetch32(s);
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uint32 f = Fetch32(s + len - 4);
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uint32 h = len;
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return fmix(Mur(f, Mur(e, Mur(d, Mur(c, Mur(b, Mur(a, h)))))));
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}
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static uint32 Hash32Len0to4(const char* s, size_t len) {
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uint32 b = 0;
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uint32 c = 9;
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for (size_t i = 0; i < len; i++) {
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signed char v = s[i];
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b = b * c1 + v;
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c ^= b;
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}
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return fmix(Mur(b, Mur(len, c)));
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}
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static uint32 Hash32Len5to12(const char* s, size_t len) {
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uint32 a = len, b = len * 5, c = 9, d = b;
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a += Fetch32(s);
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b += Fetch32(s + len - 4);
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c += Fetch32(s + ((len >> 1) & 4));
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return fmix(Mur(c, Mur(b, Mur(a, d))));
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}
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uint32 CityHash32(const char* s, size_t len) {
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if (len <= 24) {
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return len <= 12 ? (len <= 4 ? Hash32Len0to4(s, len) : Hash32Len5to12(s, len))
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: Hash32Len13to24(s, len);
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}
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// len > 24
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uint32 h = len, g = c1 * len, f = g;
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uint32 a0 = Rotate32(Fetch32(s + len - 4) * c1, 17) * c2;
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uint32 a1 = Rotate32(Fetch32(s + len - 8) * c1, 17) * c2;
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uint32 a2 = Rotate32(Fetch32(s + len - 16) * c1, 17) * c2;
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uint32 a3 = Rotate32(Fetch32(s + len - 12) * c1, 17) * c2;
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uint32 a4 = Rotate32(Fetch32(s + len - 20) * c1, 17) * c2;
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h ^= a0;
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h = Rotate32(h, 19);
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h = h * 5 + 0xe6546b64;
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h ^= a2;
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h = Rotate32(h, 19);
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h = h * 5 + 0xe6546b64;
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g ^= a1;
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g = Rotate32(g, 19);
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g = g * 5 + 0xe6546b64;
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g ^= a3;
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g = Rotate32(g, 19);
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g = g * 5 + 0xe6546b64;
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f += a4;
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f = Rotate32(f, 19);
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f = f * 5 + 0xe6546b64;
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size_t iters = (len - 1) / 20;
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do {
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uint32 a0 = Rotate32(Fetch32(s) * c1, 17) * c2;
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uint32 a1 = Fetch32(s + 4);
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uint32 a2 = Rotate32(Fetch32(s + 8) * c1, 17) * c2;
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uint32 a3 = Rotate32(Fetch32(s + 12) * c1, 17) * c2;
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uint32 a4 = Fetch32(s + 16);
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h ^= a0;
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h = Rotate32(h, 18);
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h = h * 5 + 0xe6546b64;
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f += a1;
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f = Rotate32(f, 19);
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f = f * c1;
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g += a2;
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g = Rotate32(g, 18);
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g = g * 5 + 0xe6546b64;
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h ^= a3 + a1;
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h = Rotate32(h, 19);
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h = h * 5 + 0xe6546b64;
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g ^= a4;
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g = bswap_32(g) * 5;
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h += a4 * 5;
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h = bswap_32(h);
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f += a0;
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PERMUTE3(f, h, g);
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s += 20;
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} while (--iters != 0);
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g = Rotate32(g, 11) * c1;
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g = Rotate32(g, 17) * c1;
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f = Rotate32(f, 11) * c1;
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f = Rotate32(f, 17) * c1;
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h = Rotate32(h + g, 19);
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h = h * 5 + 0xe6546b64;
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h = Rotate32(h, 17) * c1;
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h = Rotate32(h + f, 19);
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h = h * 5 + 0xe6546b64;
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h = Rotate32(h, 17) * c1;
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return h;
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}
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// Bitwise right rotate. Normally this will compile to a single
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// instruction, especially if the shift is a manifest constant.
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static uint64 Rotate(uint64 val, int shift) {
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// Avoid shifting by 64: doing so yields an undefined result.
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return shift == 0 ? val : ((val >> shift) | (val << (64 - shift)));
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}
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static uint64 ShiftMix(uint64 val) {
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return val ^ (val >> 47);
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}
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static uint64 HashLen16(uint64 u, uint64 v) {
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return Hash128to64(uint128(u, v));
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}
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static uint64 HashLen16(uint64 u, uint64 v, uint64 mul) {
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// Murmur-inspired hashing.
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uint64 a = (u ^ v) * mul;
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a ^= (a >> 47);
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uint64 b = (v ^ a) * mul;
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b ^= (b >> 47);
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b *= mul;
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return b;
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}
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static uint64 HashLen0to16(const char* s, size_t len) {
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if (len >= 8) {
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uint64 mul = k2 + len * 2;
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uint64 a = Fetch64(s) + k2;
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uint64 b = Fetch64(s + len - 8);
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uint64 c = Rotate(b, 37) * mul + a;
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uint64 d = (Rotate(a, 25) + b) * mul;
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return HashLen16(c, d, mul);
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}
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if (len >= 4) {
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uint64 mul = k2 + len * 2;
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uint64 a = Fetch32(s);
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return HashLen16(len + (a << 3), Fetch32(s + len - 4), mul);
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}
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if (len > 0) {
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uint8 a = s[0];
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uint8 b = s[len >> 1];
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uint8 c = s[len - 1];
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uint32 y = static_cast<uint32>(a) + (static_cast<uint32>(b) << 8);
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uint32 z = len + (static_cast<uint32>(c) << 2);
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return ShiftMix(y * k2 ^ z * k0) * k2;
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}
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return k2;
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}
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// This probably works well for 16-byte strings as well, but it may be overkill
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// in that case.
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static uint64 HashLen17to32(const char* s, size_t len) {
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uint64 mul = k2 + len * 2;
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uint64 a = Fetch64(s) * k1;
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uint64 b = Fetch64(s + 8);
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uint64 c = Fetch64(s + len - 8) * mul;
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uint64 d = Fetch64(s + len - 16) * k2;
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return HashLen16(Rotate(a + b, 43) + Rotate(c, 30) + d, a + Rotate(b + k2, 18) + c, mul);
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}
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// Return a 16-byte hash for 48 bytes. Quick and dirty.
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// Callers do best to use "random-looking" values for a and b.
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static pair<uint64, uint64> WeakHashLen32WithSeeds(uint64 w, uint64 x, uint64 y, uint64 z, uint64 a,
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uint64 b) {
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a += w;
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b = Rotate(b + a + z, 21);
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uint64 c = a;
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a += x;
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a += y;
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b += Rotate(a, 44);
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return make_pair(a + z, b + c);
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}
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// Return a 16-byte hash for s[0] ... s[31], a, and b. Quick and dirty.
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static pair<uint64, uint64> WeakHashLen32WithSeeds(const char* s, uint64 a, uint64 b) {
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return WeakHashLen32WithSeeds(Fetch64(s), Fetch64(s + 8), Fetch64(s + 16), Fetch64(s + 24), a,
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b);
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}
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// Return an 8-byte hash for 33 to 64 bytes.
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static uint64 HashLen33to64(const char* s, size_t len) {
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uint64 mul = k2 + len * 2;
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uint64 a = Fetch64(s) * k2;
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uint64 b = Fetch64(s + 8);
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uint64 c = Fetch64(s + len - 24);
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uint64 d = Fetch64(s + len - 32);
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uint64 e = Fetch64(s + 16) * k2;
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uint64 f = Fetch64(s + 24) * 9;
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uint64 g = Fetch64(s + len - 8);
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uint64 h = Fetch64(s + len - 16) * mul;
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uint64 u = Rotate(a + g, 43) + (Rotate(b, 30) + c) * 9;
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uint64 v = ((a + g) ^ d) + f + 1;
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uint64 w = bswap_64((u + v) * mul) + h;
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uint64 x = Rotate(e + f, 42) + c;
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uint64 y = (bswap_64((v + w) * mul) + g) * mul;
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uint64 z = e + f + c;
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a = bswap_64((x + z) * mul + y) + b;
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b = ShiftMix((z + a) * mul + d + h) * mul;
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return b + x;
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}
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uint64 CityHash64(const char* s, size_t len) {
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if (len <= 32) {
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if (len <= 16) {
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return HashLen0to16(s, len);
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} else {
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return HashLen17to32(s, len);
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}
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} else if (len <= 64) {
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return HashLen33to64(s, len);
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}
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// For strings over 64 bytes we hash the end first, and then as we
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// loop we keep 56 bytes of state: v, w, x, y, and z.
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uint64 x = Fetch64(s + len - 40);
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uint64 y = Fetch64(s + len - 16) + Fetch64(s + len - 56);
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uint64 z = HashLen16(Fetch64(s + len - 48) + len, Fetch64(s + len - 24));
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pair<uint64, uint64> v = WeakHashLen32WithSeeds(s + len - 64, len, z);
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pair<uint64, uint64> w = WeakHashLen32WithSeeds(s + len - 32, y + k1, x);
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x = x * k1 + Fetch64(s);
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|
|
||
|
// Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
|
||
|
len = (len - 1) & ~static_cast<size_t>(63);
|
||
|
do {
|
||
|
x = Rotate(x + y + v.first + Fetch64(s + 8), 37) * k1;
|
||
|
y = Rotate(y + v.second + Fetch64(s + 48), 42) * k1;
|
||
|
x ^= w.second;
|
||
|
y += v.first + Fetch64(s + 40);
|
||
|
z = Rotate(z + w.first, 33) * k1;
|
||
|
v = WeakHashLen32WithSeeds(s, v.second * k1, x + w.first);
|
||
|
w = WeakHashLen32WithSeeds(s + 32, z + w.second, y + Fetch64(s + 16));
|
||
|
std::swap(z, x);
|
||
|
s += 64;
|
||
|
len -= 64;
|
||
|
} while (len != 0);
|
||
|
return HashLen16(HashLen16(v.first, w.first) + ShiftMix(y) * k1 + z,
|
||
|
HashLen16(v.second, w.second) + x);
|
||
|
}
|
||
|
|
||
|
uint64 CityHash64WithSeed(const char* s, size_t len, uint64 seed) {
|
||
|
return CityHash64WithSeeds(s, len, k2, seed);
|
||
|
}
|
||
|
|
||
|
uint64 CityHash64WithSeeds(const char* s, size_t len, uint64 seed0, uint64 seed1) {
|
||
|
return HashLen16(CityHash64(s, len) - seed0, seed1);
|
||
|
}
|
||
|
|
||
|
// A subroutine for CityHash128(). Returns a decent 128-bit hash for strings
|
||
|
// of any length representable in signed long. Based on City and Murmur.
|
||
|
static uint128 CityMurmur(const char* s, size_t len, uint128 seed) {
|
||
|
uint64 a = Uint128Low64(seed);
|
||
|
uint64 b = Uint128High64(seed);
|
||
|
uint64 c = 0;
|
||
|
uint64 d = 0;
|
||
|
signed long l = len - 16;
|
||
|
if (l <= 0) { // len <= 16
|
||
|
a = ShiftMix(a * k1) * k1;
|
||
|
c = b * k1 + HashLen0to16(s, len);
|
||
|
d = ShiftMix(a + (len >= 8 ? Fetch64(s) : c));
|
||
|
} else { // len > 16
|
||
|
c = HashLen16(Fetch64(s + len - 8) + k1, a);
|
||
|
d = HashLen16(b + len, c + Fetch64(s + len - 16));
|
||
|
a += d;
|
||
|
do {
|
||
|
a ^= ShiftMix(Fetch64(s) * k1) * k1;
|
||
|
a *= k1;
|
||
|
b ^= a;
|
||
|
c ^= ShiftMix(Fetch64(s + 8) * k1) * k1;
|
||
|
c *= k1;
|
||
|
d ^= c;
|
||
|
s += 16;
|
||
|
l -= 16;
|
||
|
} while (l > 0);
|
||
|
}
|
||
|
a = HashLen16(a, c);
|
||
|
b = HashLen16(d, b);
|
||
|
return uint128(a ^ b, HashLen16(b, a));
|
||
|
}
|
||
|
|
||
|
uint128 CityHash128WithSeed(const char* s, size_t len, uint128 seed) {
|
||
|
if (len < 128) {
|
||
|
return CityMurmur(s, len, seed);
|
||
|
}
|
||
|
|
||
|
// We expect len >= 128 to be the common case. Keep 56 bytes of state:
|
||
|
// v, w, x, y, and z.
|
||
|
pair<uint64, uint64> v, w;
|
||
|
uint64 x = Uint128Low64(seed);
|
||
|
uint64 y = Uint128High64(seed);
|
||
|
uint64 z = len * k1;
|
||
|
v.first = Rotate(y ^ k1, 49) * k1 + Fetch64(s);
|
||
|
v.second = Rotate(v.first, 42) * k1 + Fetch64(s + 8);
|
||
|
w.first = Rotate(y + z, 35) * k1 + x;
|
||
|
w.second = Rotate(x + Fetch64(s + 88), 53) * k1;
|
||
|
|
||
|
// This is the same inner loop as CityHash64(), manually unrolled.
|
||
|
do {
|
||
|
x = Rotate(x + y + v.first + Fetch64(s + 8), 37) * k1;
|
||
|
y = Rotate(y + v.second + Fetch64(s + 48), 42) * k1;
|
||
|
x ^= w.second;
|
||
|
y += v.first + Fetch64(s + 40);
|
||
|
z = Rotate(z + w.first, 33) * k1;
|
||
|
v = WeakHashLen32WithSeeds(s, v.second * k1, x + w.first);
|
||
|
w = WeakHashLen32WithSeeds(s + 32, z + w.second, y + Fetch64(s + 16));
|
||
|
std::swap(z, x);
|
||
|
s += 64;
|
||
|
x = Rotate(x + y + v.first + Fetch64(s + 8), 37) * k1;
|
||
|
y = Rotate(y + v.second + Fetch64(s + 48), 42) * k1;
|
||
|
x ^= w.second;
|
||
|
y += v.first + Fetch64(s + 40);
|
||
|
z = Rotate(z + w.first, 33) * k1;
|
||
|
v = WeakHashLen32WithSeeds(s, v.second * k1, x + w.first);
|
||
|
w = WeakHashLen32WithSeeds(s + 32, z + w.second, y + Fetch64(s + 16));
|
||
|
std::swap(z, x);
|
||
|
s += 64;
|
||
|
len -= 128;
|
||
|
} while (LIKELY(len >= 128));
|
||
|
x += Rotate(v.first + z, 49) * k0;
|
||
|
y = y * k0 + Rotate(w.second, 37);
|
||
|
z = z * k0 + Rotate(w.first, 27);
|
||
|
w.first *= 9;
|
||
|
v.first *= k0;
|
||
|
// If 0 < len < 128, hash up to 4 chunks of 32 bytes each from the end of s.
|
||
|
for (size_t tail_done = 0; tail_done < len;) {
|
||
|
tail_done += 32;
|
||
|
y = Rotate(x + y, 42) * k0 + v.second;
|
||
|
w.first += Fetch64(s + len - tail_done + 16);
|
||
|
x = x * k0 + w.first;
|
||
|
z += w.second + Fetch64(s + len - tail_done);
|
||
|
w.second += v.first;
|
||
|
v = WeakHashLen32WithSeeds(s + len - tail_done, v.first + z, v.second);
|
||
|
v.first *= k0;
|
||
|
}
|
||
|
// At this point our 56 bytes of state should contain more than
|
||
|
// enough information for a strong 128-bit hash. We use two
|
||
|
// different 56-byte-to-8-byte hashes to get a 16-byte final result.
|
||
|
x = HashLen16(x, v.first);
|
||
|
y = HashLen16(y + z, w.first);
|
||
|
return uint128(HashLen16(x + v.second, w.second) + y, HashLen16(x + w.second, y + v.second));
|
||
|
}
|
||
|
|
||
|
uint128 CityHash128(const char* s, size_t len) {
|
||
|
return len >= 16
|
||
|
? CityHash128WithSeed(s + 16, len - 16, uint128(Fetch64(s), Fetch64(s + 8) + k0))
|
||
|
: CityHash128WithSeed(s, len, uint128(k0, k1));
|
||
|
}
|
||
|
|
||
|
#ifdef __SSE4_2__
|
||
|
#include <citycrc.h>
|
||
|
#include <nmmintrin.h>
|
||
|
|
||
|
// Requires len >= 240.
|
||
|
static void CityHashCrc256Long(const char* s, size_t len, uint32 seed, uint64* result) {
|
||
|
uint64 a = Fetch64(s + 56) + k0;
|
||
|
uint64 b = Fetch64(s + 96) + k0;
|
||
|
uint64 c = result[0] = HashLen16(b, len);
|
||
|
uint64 d = result[1] = Fetch64(s + 120) * k0 + len;
|
||
|
uint64 e = Fetch64(s + 184) + seed;
|
||
|
uint64 f = 0;
|
||
|
uint64 g = 0;
|
||
|
uint64 h = c + d;
|
||
|
uint64 x = seed;
|
||
|
uint64 y = 0;
|
||
|
uint64 z = 0;
|
||
|
|
||
|
// 240 bytes of input per iter.
|
||
|
size_t iters = len / 240;
|
||
|
len -= iters * 240;
|
||
|
do {
|
||
|
#undef CHUNK
|
||
|
#define CHUNK(r) \
|
||
|
PERMUTE3(x, z, y); \
|
||
|
b += Fetch64(s); \
|
||
|
c += Fetch64(s + 8); \
|
||
|
d += Fetch64(s + 16); \
|
||
|
e += Fetch64(s + 24); \
|
||
|
f += Fetch64(s + 32); \
|
||
|
a += b; \
|
||
|
h += f; \
|
||
|
b += c; \
|
||
|
f += d; \
|
||
|
g += e; \
|
||
|
e += z; \
|
||
|
g += x; \
|
||
|
z = _mm_crc32_u64(z, b + g); \
|
||
|
y = _mm_crc32_u64(y, e + h); \
|
||
|
x = _mm_crc32_u64(x, f + a); \
|
||
|
e = Rotate(e, r); \
|
||
|
c += e; \
|
||
|
s += 40
|
||
|
|
||
|
CHUNK(0);
|
||
|
PERMUTE3(a, h, c);
|
||
|
CHUNK(33);
|
||
|
PERMUTE3(a, h, f);
|
||
|
CHUNK(0);
|
||
|
PERMUTE3(b, h, f);
|
||
|
CHUNK(42);
|
||
|
PERMUTE3(b, h, d);
|
||
|
CHUNK(0);
|
||
|
PERMUTE3(b, h, e);
|
||
|
CHUNK(33);
|
||
|
PERMUTE3(a, h, e);
|
||
|
} while (--iters > 0);
|
||
|
|
||
|
while (len >= 40) {
|
||
|
CHUNK(29);
|
||
|
e ^= Rotate(a, 20);
|
||
|
h += Rotate(b, 30);
|
||
|
g ^= Rotate(c, 40);
|
||
|
f += Rotate(d, 34);
|
||
|
PERMUTE3(c, h, g);
|
||
|
len -= 40;
|
||
|
}
|
||
|
if (len > 0) {
|
||
|
s = s + len - 40;
|
||
|
CHUNK(33);
|
||
|
e ^= Rotate(a, 43);
|
||
|
h += Rotate(b, 42);
|
||
|
g ^= Rotate(c, 41);
|
||
|
f += Rotate(d, 40);
|
||
|
}
|
||
|
result[0] ^= h;
|
||
|
result[1] ^= g;
|
||
|
g += h;
|
||
|
a = HashLen16(a, g + z);
|
||
|
x += y << 32;
|
||
|
b += x;
|
||
|
c = HashLen16(c, z) + h;
|
||
|
d = HashLen16(d, e + result[0]);
|
||
|
g += e;
|
||
|
h += HashLen16(x, f);
|
||
|
e = HashLen16(a, d) + g;
|
||
|
z = HashLen16(b, c) + a;
|
||
|
y = HashLen16(g, h) + c;
|
||
|
result[0] = e + z + y + x;
|
||
|
a = ShiftMix((a + y) * k0) * k0 + b;
|
||
|
result[1] += a + result[0];
|
||
|
a = ShiftMix(a * k0) * k0 + c;
|
||
|
result[2] = a + result[1];
|
||
|
a = ShiftMix((a + e) * k0) * k0;
|
||
|
result[3] = a + result[2];
|
||
|
}
|
||
|
|
||
|
// Requires len < 240.
|
||
|
static void CityHashCrc256Short(const char* s, size_t len, uint64* result) {
|
||
|
char buf[240];
|
||
|
memcpy(buf, s, len);
|
||
|
memset(buf + len, 0, 240 - len);
|
||
|
CityHashCrc256Long(buf, 240, ~static_cast<uint32>(len), result);
|
||
|
}
|
||
|
|
||
|
void CityHashCrc256(const char* s, size_t len, uint64* result) {
|
||
|
if (LIKELY(len >= 240)) {
|
||
|
CityHashCrc256Long(s, len, 0, result);
|
||
|
} else {
|
||
|
CityHashCrc256Short(s, len, result);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
uint128 CityHashCrc128WithSeed(const char* s, size_t len, uint128 seed) {
|
||
|
if (len <= 900) {
|
||
|
return CityHash128WithSeed(s, len, seed);
|
||
|
} else {
|
||
|
uint64 result[4];
|
||
|
CityHashCrc256(s, len, result);
|
||
|
uint64 u = Uint128High64(seed) + result[0];
|
||
|
uint64 v = Uint128Low64(seed) + result[1];
|
||
|
return uint128(HashLen16(u, v + result[2]), HashLen16(Rotate(v, 32), u * k0 + result[3]));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
uint128 CityHashCrc128(const char* s, size_t len) {
|
||
|
if (len <= 900) {
|
||
|
return CityHash128(s, len);
|
||
|
} else {
|
||
|
uint64 result[4];
|
||
|
CityHashCrc256(s, len, result);
|
||
|
return uint128(result[2], result[3]);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#endif
|