Erixonich commented on code in PR #7750: URL: https://github.com/apache/ignite-3/pull/7750#discussion_r2918285604
########## modules/platforms/cpp/ignite/common/detail/Murmur3Hash.cpp: ########## @@ -0,0 +1,190 @@ +// Licensed to the Apache Software Foundation (ASF) under one or more +// contributor license agreements. See the NOTICE file distributed with +// this work for additional information regarding copyright ownership. +// The ASF licenses this file to You under the Apache License, Version 2.0 +// (the "License"); you may not use this file except in compliance with +// the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// + +// +// Created by erixon on 2026-03-09. +// + +#include "Murmur3Hash.h" + +//----------------------------------------------------------------------------- +// 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. + + +//----------------------------------------------------------------------------- +// Platform-specific functions and macros + +// Microsoft Visual Studio + +#if defined(_MSC_VER) + +#define FORCE_INLINE __forceinline + +#include <stdlib.h> + +#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) + +#define FORCE_INLINE inline __attribute__((always_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 getblock32 ( const uint32_t * p, int i ) +{ + return p[i]; +} + +FORCE_INLINE uint64_t getblock64 ( const uint64_t * p, int i ) +{ + return p[i]; +} + +//----------------------------------------------------------------------------- +// Finalization mix - force all bits of a hash block to avalanche + +FORCE_INLINE uint32_t fmix32 ( uint32_t h ) +{ + h ^= h >> 16; + h *= 0x85ebca6b; + h ^= h >> 13; + h *= 0xc2b2ae35; + h ^= h >> 16; + + return h; +} + +//---------- + +FORCE_INLINE uint64_t fmix64 ( uint64_t k ) +{ + k ^= k >> 33; + k *= BIG_CONSTANT(0xff51afd7ed558ccd); + k ^= k >> 33; + k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53); + k ^= k >> 33; + + return k; +} + +void MurmurHash3_x64_128 ( const void * key, std::size_t len, + const uint64_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 = getblock64(blocks,i*2+0); + uint64_t k2 = getblock64(blocks,i*2+1); Review Comment: I'm not sure, but x86 allows unaligned access, only issue would be is performance. @isapego WDYT? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
