Merge pull request #3389 from yuriks/cityhash
Common: Replace MurmurHash3 with CityHash64
This commit is contained in:
		| @@ -32,6 +32,8 @@ add_library(common STATIC | ||||
|     break_points.cpp | ||||
|     break_points.h | ||||
|     chunk_file.h | ||||
|     cityhash.cpp | ||||
|     cityhash.h | ||||
|     code_block.h | ||||
|     color.h | ||||
|     common_funcs.h | ||||
| @@ -39,7 +41,6 @@ add_library(common STATIC | ||||
|     common_types.h | ||||
|     file_util.cpp | ||||
|     file_util.h | ||||
|     hash.cpp | ||||
|     hash.h | ||||
|     linear_disk_cache.h | ||||
|     logging/backend.cpp | ||||
|   | ||||
							
								
								
									
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							| @@ -0,0 +1,340 @@ | ||||
| // Copyright (c) 2011 Google, Inc. | ||||
| // | ||||
| // Permission is hereby granted, free of charge, to any person obtaining a copy | ||||
| // of this software and associated documentation files (the "Software"), to deal | ||||
| // in the Software without restriction, including without limitation the rights | ||||
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | ||||
| // copies of the Software, and to permit persons to whom the Software is | ||||
| // furnished to do so, subject to the following conditions: | ||||
| // | ||||
| // The above copyright notice and this permission notice shall be included in | ||||
| // all copies or substantial portions of the Software. | ||||
| // | ||||
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||||
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||||
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | ||||
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | ||||
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | ||||
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | ||||
| // THE SOFTWARE. | ||||
| // | ||||
| // CityHash, by Geoff Pike and Jyrki Alakuijala | ||||
| // | ||||
| // This file provides CityHash64() and related functions. | ||||
| // | ||||
| // It's probably possible to create even faster hash functions by | ||||
| // writing a program that systematically explores some of the space of | ||||
| // possible hash functions, by using SIMD instructions, or by | ||||
| // compromising on hash quality. | ||||
|  | ||||
| #include <algorithm> | ||||
| #include <string.h> // for memcpy and memset | ||||
| #include "cityhash.h" | ||||
| #include "common/swap.h" | ||||
|  | ||||
| // #include "config.h" | ||||
| #ifdef __GNUC__ | ||||
| #define HAVE_BUILTIN_EXPECT 1 | ||||
| #endif | ||||
| #ifdef COMMON_BIG_ENDIAN | ||||
| #define WORDS_BIGENDIAN 1 | ||||
| #endif | ||||
|  | ||||
| using namespace std; | ||||
|  | ||||
| typedef uint8_t uint8; | ||||
| typedef uint32_t uint32; | ||||
| typedef uint64_t uint64; | ||||
|  | ||||
| namespace Common { | ||||
|  | ||||
| static uint64 UNALIGNED_LOAD64(const char* p) { | ||||
|     uint64 result; | ||||
|     memcpy(&result, p, sizeof(result)); | ||||
|     return result; | ||||
| } | ||||
|  | ||||
| static uint32 UNALIGNED_LOAD32(const char* p) { | ||||
|     uint32 result; | ||||
|     memcpy(&result, p, sizeof(result)); | ||||
|     return result; | ||||
| } | ||||
|  | ||||
| #ifdef WORDS_BIGENDIAN | ||||
| #define uint32_in_expected_order(x) (swap32(x)) | ||||
| #define uint64_in_expected_order(x) (swap64(x)) | ||||
| #else | ||||
| #define uint32_in_expected_order(x) (x) | ||||
| #define uint64_in_expected_order(x) (x) | ||||
| #endif | ||||
|  | ||||
| #if !defined(LIKELY) | ||||
| #if HAVE_BUILTIN_EXPECT | ||||
| #define LIKELY(x) (__builtin_expect(!!(x), 1)) | ||||
| #else | ||||
| #define LIKELY(x) (x) | ||||
| #endif | ||||
| #endif | ||||
|  | ||||
| static uint64 Fetch64(const char* p) { | ||||
|     return uint64_in_expected_order(UNALIGNED_LOAD64(p)); | ||||
| } | ||||
|  | ||||
| static uint32 Fetch32(const char* p) { | ||||
|     return uint32_in_expected_order(UNALIGNED_LOAD32(p)); | ||||
| } | ||||
|  | ||||
| // Some primes between 2^63 and 2^64 for various uses. | ||||
| static const uint64 k0 = 0xc3a5c85c97cb3127ULL; | ||||
| static const uint64 k1 = 0xb492b66fbe98f273ULL; | ||||
| static const uint64 k2 = 0x9ae16a3b2f90404fULL; | ||||
|  | ||||
| // Bitwise right rotate.  Normally this will compile to a single | ||||
| // instruction, especially if the shift is a manifest constant. | ||||
| static uint64 Rotate(uint64 val, int shift) { | ||||
|     // Avoid shifting by 64: doing so yields an undefined result. | ||||
|     return shift == 0 ? val : ((val >> shift) | (val << (64 - shift))); | ||||
| } | ||||
|  | ||||
| static uint64 ShiftMix(uint64 val) { | ||||
|     return val ^ (val >> 47); | ||||
| } | ||||
|  | ||||
| static uint64 HashLen16(uint64 u, uint64 v) { | ||||
|     return Hash128to64(uint128(u, v)); | ||||
| } | ||||
|  | ||||
| static uint64 HashLen16(uint64 u, uint64 v, uint64 mul) { | ||||
|     // Murmur-inspired hashing. | ||||
|     uint64 a = (u ^ v) * mul; | ||||
|     a ^= (a >> 47); | ||||
|     uint64 b = (v ^ a) * mul; | ||||
|     b ^= (b >> 47); | ||||
|     b *= mul; | ||||
|     return b; | ||||
| } | ||||
|  | ||||
| static uint64 HashLen0to16(const char* s, size_t len) { | ||||
|     if (len >= 8) { | ||||
|         uint64 mul = k2 + len * 2; | ||||
|         uint64 a = Fetch64(s) + k2; | ||||
|         uint64 b = Fetch64(s + len - 8); | ||||
|         uint64 c = Rotate(b, 37) * mul + a; | ||||
|         uint64 d = (Rotate(a, 25) + b) * mul; | ||||
|         return HashLen16(c, d, mul); | ||||
|     } | ||||
|     if (len >= 4) { | ||||
|         uint64 mul = k2 + len * 2; | ||||
|         uint64 a = Fetch32(s); | ||||
|         return HashLen16(len + (a << 3), Fetch32(s + len - 4), mul); | ||||
|     } | ||||
|     if (len > 0) { | ||||
|         uint8 a = s[0]; | ||||
|         uint8 b = s[len >> 1]; | ||||
|         uint8 c = s[len - 1]; | ||||
|         uint32 y = static_cast<uint32>(a) + (static_cast<uint32>(b) << 8); | ||||
|         uint32 z = static_cast<uint32>(len) + (static_cast<uint32>(c) << 2); | ||||
|         return ShiftMix(y * k2 ^ z * k0) * k2; | ||||
|     } | ||||
|     return k2; | ||||
| } | ||||
|  | ||||
| // This probably works well for 16-byte strings as well, but it may be overkill | ||||
| // in that case. | ||||
| static uint64 HashLen17to32(const char* s, size_t len) { | ||||
|     uint64 mul = k2 + len * 2; | ||||
|     uint64 a = Fetch64(s) * k1; | ||||
|     uint64 b = Fetch64(s + 8); | ||||
|     uint64 c = Fetch64(s + len - 8) * mul; | ||||
|     uint64 d = Fetch64(s + len - 16) * k2; | ||||
|     return HashLen16(Rotate(a + b, 43) + Rotate(c, 30) + d, a + Rotate(b + k2, 18) + c, mul); | ||||
| } | ||||
|  | ||||
| // Return a 16-byte hash for 48 bytes.  Quick and dirty. | ||||
| // Callers do best to use "random-looking" values for a and b. | ||||
| static pair<uint64, uint64> WeakHashLen32WithSeeds(uint64 w, uint64 x, uint64 y, uint64 z, uint64 a, | ||||
|                                                    uint64 b) { | ||||
|     a += w; | ||||
|     b = Rotate(b + a + z, 21); | ||||
|     uint64 c = a; | ||||
|     a += x; | ||||
|     a += y; | ||||
|     b += Rotate(a, 44); | ||||
|     return make_pair(a + z, b + c); | ||||
| } | ||||
|  | ||||
| // Return a 16-byte hash for s[0] ... s[31], a, and b.  Quick and dirty. | ||||
| static pair<uint64, uint64> WeakHashLen32WithSeeds(const char* s, uint64 a, uint64 b) { | ||||
|     return WeakHashLen32WithSeeds(Fetch64(s), Fetch64(s + 8), Fetch64(s + 16), Fetch64(s + 24), a, | ||||
|                                   b); | ||||
| } | ||||
|  | ||||
| // Return an 8-byte hash for 33 to 64 bytes. | ||||
| static uint64 HashLen33to64(const char* s, size_t len) { | ||||
|     uint64 mul = k2 + len * 2; | ||||
|     uint64 a = Fetch64(s) * k2; | ||||
|     uint64 b = Fetch64(s + 8); | ||||
|     uint64 c = Fetch64(s + len - 24); | ||||
|     uint64 d = Fetch64(s + len - 32); | ||||
|     uint64 e = Fetch64(s + 16) * k2; | ||||
|     uint64 f = Fetch64(s + 24) * 9; | ||||
|     uint64 g = Fetch64(s + len - 8); | ||||
|     uint64 h = Fetch64(s + len - 16) * mul; | ||||
|     uint64 u = Rotate(a + g, 43) + (Rotate(b, 30) + c) * 9; | ||||
|     uint64 v = ((a + g) ^ d) + f + 1; | ||||
|     uint64 w = swap64((u + v) * mul) + h; | ||||
|     uint64 x = Rotate(e + f, 42) + c; | ||||
|     uint64 y = (swap64((v + w) * mul) + g) * mul; | ||||
|     uint64 z = e + f + c; | ||||
|     a = swap64((x + z) * mul + y) + b; | ||||
|     b = ShiftMix((z + a) * mul + d + h) * mul; | ||||
|     return b + x; | ||||
| } | ||||
|  | ||||
| uint64 CityHash64(const char* s, size_t len) { | ||||
|     if (len <= 32) { | ||||
|         if (len <= 16) { | ||||
|             return HashLen0to16(s, len); | ||||
|         } else { | ||||
|             return HashLen17to32(s, len); | ||||
|         } | ||||
|     } else if (len <= 64) { | ||||
|         return HashLen33to64(s, len); | ||||
|     } | ||||
|  | ||||
|     // For strings over 64 bytes we hash the end first, and then as we | ||||
|     // loop we keep 56 bytes of state: v, w, x, y, and z. | ||||
|     uint64 x = Fetch64(s + len - 40); | ||||
|     uint64 y = Fetch64(s + len - 16) + Fetch64(s + len - 56); | ||||
|     uint64 z = HashLen16(Fetch64(s + len - 48) + len, Fetch64(s + len - 24)); | ||||
|     pair<uint64, uint64> v = WeakHashLen32WithSeeds(s + len - 64, len, z); | ||||
|     pair<uint64, uint64> w = WeakHashLen32WithSeeds(s + len - 32, y + k1, x); | ||||
|     x = x * k1 + Fetch64(s); | ||||
|  | ||||
|     // 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 = static_cast<long>(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)); | ||||
| } | ||||
|  | ||||
| } // namespace Common | ||||
							
								
								
									
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							| @@ -0,0 +1,110 @@ | ||||
| // Copyright (c) 2011 Google, Inc. | ||||
| // | ||||
| // Permission is hereby granted, free of charge, to any person obtaining a copy | ||||
| // of this software and associated documentation files (the "Software"), to deal | ||||
| // in the Software without restriction, including without limitation the rights | ||||
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | ||||
| // copies of the Software, and to permit persons to whom the Software is | ||||
| // furnished to do so, subject to the following conditions: | ||||
| // | ||||
| // The above copyright notice and this permission notice shall be included in | ||||
| // all copies or substantial portions of the Software. | ||||
| // | ||||
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||||
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||||
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | ||||
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | ||||
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | ||||
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | ||||
| // THE SOFTWARE. | ||||
| // | ||||
| // CityHash, by Geoff Pike and Jyrki Alakuijala | ||||
| // | ||||
| // http://code.google.com/p/cityhash/ | ||||
| // | ||||
| // This file provides a few functions for hashing strings.  All of them are | ||||
| // high-quality functions in the sense that they pass standard tests such | ||||
| // as Austin Appleby's SMHasher.  They are also fast. | ||||
| // | ||||
| // For 64-bit x86 code, on short strings, we don't know of anything faster than | ||||
| // CityHash64 that is of comparable quality.  We believe our nearest competitor | ||||
| // is Murmur3.  For 64-bit x86 code, CityHash64 is an excellent choice for hash | ||||
| // tables and most other hashing (excluding cryptography). | ||||
| // | ||||
| // For 64-bit x86 code, on long strings, the picture is more complicated. | ||||
| // On many recent Intel CPUs, such as Nehalem, Westmere, Sandy Bridge, etc., | ||||
| // CityHashCrc128 appears to be faster than all competitors of comparable | ||||
| // quality.  CityHash128 is also good but not quite as fast.  We believe our | ||||
| // nearest competitor is Bob Jenkins' Spooky.  We don't have great data for | ||||
| // other 64-bit CPUs, but for long strings we know that Spooky is slightly | ||||
| // faster than CityHash on some relatively recent AMD x86-64 CPUs, for example. | ||||
| // Note that CityHashCrc128 is declared in citycrc.h. | ||||
| // | ||||
| // For 32-bit x86 code, we don't know of anything faster than CityHash32 that | ||||
| // is of comparable quality.  We believe our nearest competitor is Murmur3A. | ||||
| // (On 64-bit CPUs, it is typically faster to use the other CityHash variants.) | ||||
| // | ||||
| // Functions in the CityHash family are not suitable for cryptography. | ||||
| // | ||||
| // Please see CityHash's README file for more details on our performance | ||||
| // measurements and so on. | ||||
| // | ||||
| // WARNING: This code has been only lightly tested on big-endian platforms! | ||||
| // It is known to work well on little-endian platforms that have a small penalty | ||||
| // for unaligned reads, such as current Intel and AMD moderate-to-high-end CPUs. | ||||
| // It should work on all 32-bit and 64-bit platforms that allow unaligned reads; | ||||
| // bug reports are welcome. | ||||
| // | ||||
| // By the way, for some hash functions, given strings a and b, the hash | ||||
| // of a+b is easily derived from the hashes of a and b.  This property | ||||
| // doesn't hold for any hash functions in this file. | ||||
|  | ||||
| #pragma once | ||||
|  | ||||
| #include <utility> | ||||
| #include <stdint.h> | ||||
| #include <stdlib.h> // for size_t. | ||||
|  | ||||
| namespace Common { | ||||
|  | ||||
| typedef std::pair<uint64_t, uint64_t> uint128; | ||||
|  | ||||
| inline uint64_t Uint128Low64(const uint128& x) { | ||||
|     return x.first; | ||||
| } | ||||
| inline uint64_t Uint128High64(const uint128& x) { | ||||
|     return x.second; | ||||
| } | ||||
|  | ||||
| // Hash function for a byte array. | ||||
| uint64_t CityHash64(const char* buf, size_t len); | ||||
|  | ||||
| // Hash function for a byte array.  For convenience, a 64-bit seed is also | ||||
| // hashed into the result. | ||||
| uint64_t CityHash64WithSeed(const char* buf, size_t len, uint64_t seed); | ||||
|  | ||||
| // Hash function for a byte array.  For convenience, two seeds are also | ||||
| // hashed into the result. | ||||
| uint64_t CityHash64WithSeeds(const char* buf, size_t len, uint64_t seed0, uint64_t seed1); | ||||
|  | ||||
| // Hash function for a byte array. | ||||
| uint128 CityHash128(const char* s, size_t len); | ||||
|  | ||||
| // Hash function for a byte array.  For convenience, a 128-bit seed is also | ||||
| // hashed into the result. | ||||
| uint128 CityHash128WithSeed(const char* s, size_t len, uint128 seed); | ||||
|  | ||||
| // Hash 128 input bits down to 64 bits of output. | ||||
| // This is intended to be a reasonably good hash function. | ||||
| inline uint64_t Hash128to64(const uint128& x) { | ||||
|     // Murmur-inspired hashing. | ||||
|     const uint64_t kMul = 0x9ddfea08eb382d69ULL; | ||||
|     uint64_t a = (Uint128Low64(x) ^ Uint128High64(x)) * kMul; | ||||
|     a ^= (a >> 47); | ||||
|     uint64_t b = (Uint128High64(x) ^ a) * kMul; | ||||
|     b ^= (b >> 47); | ||||
|     b *= kMul; | ||||
|     return b; | ||||
| } | ||||
|  | ||||
| } // namespace Common | ||||
| @@ -1,141 +0,0 @@ | ||||
| // Copyright 2015 Citra Emulator Project | ||||
| // Licensed under GPLv2 or any later version | ||||
| // Refer to the license.txt file included. | ||||
|  | ||||
| #if defined(_MSC_VER) | ||||
| #include <stdlib.h> | ||||
| #endif | ||||
| #include "common/common_funcs.h" | ||||
| #include "common/common_types.h" | ||||
| #include "common/hash.h" | ||||
|  | ||||
| namespace Common { | ||||
|  | ||||
| // MurmurHash3 was written by Austin Appleby, and is placed in the public | ||||
| // domain. The author hereby disclaims copyright to this source code. | ||||
|  | ||||
| // Block read - if your platform needs to do endian-swapping or can only handle aligned reads, do | ||||
| // the conversion here | ||||
| static FORCE_INLINE u64 getblock64(const u64* p, size_t i) { | ||||
|     return p[i]; | ||||
| } | ||||
|  | ||||
| // Finalization mix - force all bits of a hash block to avalanche | ||||
| static FORCE_INLINE u64 fmix64(u64 k) { | ||||
|     k ^= k >> 33; | ||||
|     k *= 0xff51afd7ed558ccdllu; | ||||
|     k ^= k >> 33; | ||||
|     k *= 0xc4ceb9fe1a85ec53llu; | ||||
|     k ^= k >> 33; | ||||
|  | ||||
|     return k; | ||||
| } | ||||
|  | ||||
| // This is the 128-bit variant of the MurmurHash3 hash function that is targeted for 64-bit | ||||
| // platforms (MurmurHash3_x64_128). It was taken from: | ||||
| // https://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp | ||||
| void MurmurHash3_128(const void* key, size_t len, u32 seed, void* out) { | ||||
|     const u8* data = (const u8*)key; | ||||
|     const size_t nblocks = len / 16; | ||||
|  | ||||
|     u64 h1 = seed; | ||||
|     u64 h2 = seed; | ||||
|  | ||||
|     const u64 c1 = 0x87c37b91114253d5llu; | ||||
|     const u64 c2 = 0x4cf5ad432745937fllu; | ||||
|  | ||||
|     // Body | ||||
|  | ||||
|     const u64* blocks = (const u64*)(data); | ||||
|  | ||||
|     for (size_t i = 0; i < nblocks; i++) { | ||||
|         u64 k1 = getblock64(blocks, i * 2 + 0); | ||||
|         u64 k2 = getblock64(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 u8* tail = (const u8*)(data + nblocks * 16); | ||||
|  | ||||
|     u64 k1 = 0; | ||||
|     u64 k2 = 0; | ||||
|  | ||||
|     switch (len & 15) { | ||||
|     case 15: | ||||
|         k2 ^= ((u64)tail[14]) << 48; | ||||
|     case 14: | ||||
|         k2 ^= ((u64)tail[13]) << 40; | ||||
|     case 13: | ||||
|         k2 ^= ((u64)tail[12]) << 32; | ||||
|     case 12: | ||||
|         k2 ^= ((u64)tail[11]) << 24; | ||||
|     case 11: | ||||
|         k2 ^= ((u64)tail[10]) << 16; | ||||
|     case 10: | ||||
|         k2 ^= ((u64)tail[9]) << 8; | ||||
|     case 9: | ||||
|         k2 ^= ((u64)tail[8]) << 0; | ||||
|         k2 *= c2; | ||||
|         k2 = _rotl64(k2, 33); | ||||
|         k2 *= c1; | ||||
|         h2 ^= k2; | ||||
|  | ||||
|     case 8: | ||||
|         k1 ^= ((u64)tail[7]) << 56; | ||||
|     case 7: | ||||
|         k1 ^= ((u64)tail[6]) << 48; | ||||
|     case 6: | ||||
|         k1 ^= ((u64)tail[5]) << 40; | ||||
|     case 5: | ||||
|         k1 ^= ((u64)tail[4]) << 32; | ||||
|     case 4: | ||||
|         k1 ^= ((u64)tail[3]) << 24; | ||||
|     case 3: | ||||
|         k1 ^= ((u64)tail[2]) << 16; | ||||
|     case 2: | ||||
|         k1 ^= ((u64)tail[1]) << 8; | ||||
|     case 1: | ||||
|         k1 ^= ((u64)tail[0]) << 0; | ||||
|         k1 *= c1; | ||||
|         k1 = _rotl64(k1, 31); | ||||
|         k1 *= c2; | ||||
|         h1 ^= k1; | ||||
|     }; | ||||
|  | ||||
|     // Finalization | ||||
|  | ||||
|     h1 ^= len; | ||||
|     h2 ^= len; | ||||
|  | ||||
|     h1 += h2; | ||||
|     h2 += h1; | ||||
|  | ||||
|     h1 = fmix64(h1); | ||||
|     h2 = fmix64(h2); | ||||
|  | ||||
|     h1 += h2; | ||||
|     h2 += h1; | ||||
|  | ||||
|     ((u64*)out)[0] = h1; | ||||
|     ((u64*)out)[1] = h2; | ||||
| } | ||||
|  | ||||
| } // namespace Common | ||||
| @@ -5,12 +5,11 @@ | ||||
| #pragma once | ||||
|  | ||||
| #include <cstddef> | ||||
| #include "common/cityhash.h" | ||||
| #include "common/common_types.h" | ||||
|  | ||||
| namespace Common { | ||||
|  | ||||
| void MurmurHash3_128(const void* key, size_t len, u32 seed, void* out); | ||||
|  | ||||
| /** | ||||
|  * Computes a 64-bit hash over the specified block of data | ||||
|  * @param data Block of data to compute hash over | ||||
| @@ -18,9 +17,20 @@ void MurmurHash3_128(const void* key, size_t len, u32 seed, void* out); | ||||
|  * @returns 64-bit hash value that was computed over the data block | ||||
|  */ | ||||
| static inline u64 ComputeHash64(const void* data, size_t len) { | ||||
|     u64 res[2]; | ||||
|     MurmurHash3_128(data, len, 0, res); | ||||
|     return res[0]; | ||||
|     return CityHash64(static_cast<const char*>(data), len); | ||||
| } | ||||
|  | ||||
| /** | ||||
|  * Computes a 64-bit hash of a struct. In addition to being POD (trivially copyable and having | ||||
|  * standard layout), it is also critical that either the struct includes no padding, or that any | ||||
|  * padding is initialized to a known value by memsetting the struct to 0 before filling it in. | ||||
|  */ | ||||
| template <typename T> | ||||
| static inline u64 ComputeStructHash64(const T& data) { | ||||
|     static_assert( | ||||
|         std::is_trivially_copyable<T>::value && std::is_standard_layout<T>::value, | ||||
|         "Type passed to ComputeStructHash64 must be trivially copyable and standard layout"); | ||||
|     return ComputeHash64(&data, sizeof(data)); | ||||
| } | ||||
|  | ||||
| } // namespace Common | ||||
|   | ||||
| @@ -65,6 +65,7 @@ PicaShaderConfig PicaShaderConfig::BuildFromRegs(const Pica::Regs& regs) { | ||||
|     PicaShaderConfig res; | ||||
|  | ||||
|     auto& state = res.state; | ||||
|     // Memset structure to zero padding bits, so that they will be deterministic when hashing | ||||
|     std::memset(&state, 0, sizeof(PicaShaderConfig::State)); | ||||
|  | ||||
|     state.scissor_test_mode = regs.rasterizer.scissor_test.mode; | ||||
|   | ||||
| @@ -131,10 +131,6 @@ union PicaShaderConfig { | ||||
|  | ||||
|     } state; | ||||
| }; | ||||
| #if (__GNUC__ >= 5) || defined(__clang__) || defined(_MSC_VER) | ||||
| static_assert(std::is_trivially_copyable<PicaShaderConfig::State>::value, | ||||
|               "PicaShaderConfig::State must be trivially copyable"); | ||||
| #endif | ||||
|  | ||||
| /** | ||||
|  * Generates the GLSL vertex shader program source code for the current Pica state | ||||
| @@ -156,7 +152,7 @@ namespace std { | ||||
| template <> | ||||
| struct hash<GLShader::PicaShaderConfig> { | ||||
|     size_t operator()(const GLShader::PicaShaderConfig& k) const { | ||||
|         return Common::ComputeHash64(&k.state, sizeof(GLShader::PicaShaderConfig::State)); | ||||
|         return Common::ComputeStructHash64(k.state); | ||||
|     } | ||||
| }; | ||||
| } // namespace std | ||||
|   | ||||
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