fasthash: add initial implementation

This commit is contained in:
Danny Robson 2015-05-28 12:17:25 +10:00
parent 78f61af84c
commit 3a4fed804a
4 changed files with 147 additions and 3 deletions

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@ -52,28 +52,29 @@ UTIL_FILES = \
fourcc.hpp \ fourcc.hpp \
guid.cpp \ guid.cpp \
guid.hpp \ guid.hpp \
hash.hpp \
hash.cpp \
hash/adler.cpp \ hash/adler.cpp \
hash/adler.hpp \ hash/adler.hpp \
hash/bsdsum.cpp \ hash/bsdsum.cpp \
hash/bsdsum.hpp \ hash/bsdsum.hpp \
hash.cpp \
hash/crc.cpp \ hash/crc.cpp \
hash/crc.hpp \ hash/crc.hpp \
hash/fasthash.cpp \
hash/fletcher.hpp \ hash/fletcher.hpp \
hash/hmac.cpp \ hash/hmac.cpp \
hash/hmac.hpp \ hash/hmac.hpp \
hash/hotp.cpp \ hash/hotp.cpp \
hash/hotp.hpp \ hash/hotp.hpp \
hash.hpp \
hash/md2.cpp \ hash/md2.cpp \
hash/md2.hpp \ hash/md2.hpp \
hash/md4.cpp \ hash/md4.cpp \
hash/md4.hpp \ hash/md4.hpp \
hash/md5.cpp \ hash/md5.cpp \
hash/md5.hpp \ hash/md5.hpp \
hash/murmur.hpp \
hash/murmur/common.cpp \ hash/murmur/common.cpp \
hash/murmur/common.hpp \ hash/murmur/common.hpp \
hash/murmur.hpp \
hash/murmur/murmur1.cpp \ hash/murmur/murmur1.cpp \
hash/murmur/murmur1.hpp \ hash/murmur/murmur1.hpp \
hash/murmur/murmur2.cpp \ hash/murmur/murmur2.cpp \
@ -292,6 +293,7 @@ TEST_BIN = \
test/fixed \ test/fixed \
test/float \ test/float \
test/hash/murmur \ test/hash/murmur \
test/hash/fasthash \
test/hmac \ test/hmac \
test/hotp \ test/hotp \
test/hton \ test/hton \

70
hash/fasthash.cpp Normal file
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@ -0,0 +1,70 @@
/*
* Licensed 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.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#include "fasthash.hpp"
///////////////////////////////////////////////////////////////////////////////
uint64_t
util::hash::fasthash::mix (uint64_t v)
{
v ^= v >> 23;
v *= 0x2127599bf4325c37;
v ^= v >> 47;
return v;
}
///////////////////////////////////////////////////////////////////////////////
uint64_t
util::hash::fasthash::hash64 (const void *restrict data, size_t len, uint64_t seed)
{
static const uint64_t m = 0x880355f21e6d1965;
uint64_t result = seed ^ (len * m);
auto cursor = reinterpret_cast<const uint64_t*> (data);
auto last = cursor + len / sizeof (*cursor);
for (; cursor < last; ++cursor) {
result ^= mix (*cursor);
result *= m;
}
size_t remain = len % sizeof (*cursor);
if (remain) {
auto tail = reinterpret_cast<const uint8_t*> (cursor);
uint64_t accum = 0;
for (size_t i = 0; i < remain; ++i)
accum ^= uint64_t {tail[i]} << i * 8;
result ^= mix (accum);
result *= m;
}
return mix (result);
}
//-----------------------------------------------------------------------------
uint32_t
util::hash::fasthash::hash32 (const void *restrict data, size_t len, uint32_t seed)
{
uint64_t h = hash64 (data, len, seed);
return h - (h >> 32);
}

33
hash/fasthash.hpp Normal file
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@ -0,0 +1,33 @@
/*
* Licensed 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.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#ifndef __UTIL_HASH_FASTHASH_HPP
#define __UTIL_HASH_FASTHASH_HPP
#include <cstddef>
#include <cstdint>
// Zilong Tan's FastHash, via George Marsaglia's "Xorshift RNGs"
namespace util { namespace hash { namespace fasthash {
uint64_t mix (uint64_t);
uint32_t hash32 (const void *restrict data, size_t len, uint32_t seed);
uint64_t hash64 (const void *restrict data, size_t len, uint64_t seed);
} } }
#endif

39
test/hash/fasthash.cpp Normal file
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@ -0,0 +1,39 @@
#include "hash/fasthash.hpp"
#include "tap.hpp"
#include <cstring>
int
main (void)
{
util::TAP::logger tap;
static const struct {
uint32_t seed32;
uint32_t hash32;
uint64_t seed64;
uint64_t hash64;
const char *str;
} TESTS[] = {
{ 0x00000000, 0x00000000, 0x0000000000000000, 0x0000000000000000, "" },
{ 0x00000001, 0xd30ac4de, 0x0000000000000001, 0x2127599bf4321e79, "" },
{ 0xffffffff, 0xf5c7b4b0, 0xffffffffffffffff, 0x9b4792000001368f, "" },
{ 0xf5c7b4b0, 0x228128b7, 0x9b4792000001368f, 0x67a642098cc81da6, "a" },
{ 0x228128b7, 0x8400568d, 0x67a642098cc81da6, 0xc906440e03ce99a8, "abc" },
{ 0x8400568d, 0x12b4858b, 0x67a642098cc81da6, 0x1a36fbf3d71b0737, "message digest" },
{ 0x12b4858b, 0x730b822e, 0x1a36fbf3d71b0737, 0x7b48e31e3ac40a0f, "abcdefghijklmnopqrstuvwxyz" },
};
bool success32 = true;
bool success64 = true;
for (const auto &t: TESTS) {
success32 = success32 && t.hash32 == util::hash::fasthash::hash32 (t.str, strlen (t.str), t.seed32);
success64 = success64 && t.hash64 == util::hash::fasthash::hash64 (t.str, strlen (t.str), t.seed64);
}
tap.expect (success32, "fasthash32");
tap.expect (success64, "fasthash64");
return tap.status ();
}