Mirrors/bx
1
0
Fork 0
mirror of https://github.com/bkaradzic/bx.git synced 2026-02-17 20:52:37 +01:00
Code Issues Packages Projects Releases Wiki Activity

Cleanup.

Browse Source
This commit is contained in:
Branimir Karadžić
2017-01-20 09:31:26 -08:00
parent e98a802f09
commit 393a86a849
2 changed files with 179 additions and 133 deletions
Download Patch File Download Diff File Expand all files Collapse all files

158
include/bx/hash.h
View File

@@ -10,135 +10,37 @@
namespace bx
{
// MurmurHash2 was written by Austin Appleby, and is placed in the public
// domain. The author hereby disclaims copyright to this source code.
#define MURMUR_M 0x5bd1e995
#define MURMUR_R 24
#define mmix(_h, _k) { _k *= MURMUR_M; _k ^= _k >> MURMUR_R; _k *= MURMUR_M; _h *= MURMUR_M; _h ^= _k; }
/// MurmurHash2 was written by Austin Appleby, and is placed in the public
/// domain. The author hereby disclaims copyright to this source code.
///
class HashMurmur2A
{
public:
void begin(uint32_t _seed = 0)
{
m_hash = _seed;
m_tail = 0;
m_count = 0;
m_size = 0;
}
///
void begin(uint32_t _seed = 0);
void add(const void* _data, int _len)
{
if (BX_UNLIKELY(!isAligned(_data, 4) ) )
{
addUnaligned(_data, _len);
return;
}
///
void add(const void* _data, int _len);
addAligned(_data, _len);
}
///
void addAligned(const void* _data, int _len);
void addAligned(const void* _data, int _len)
{
const uint8_t* data = (const uint8_t*)_data;
m_size += _len;
mixTail(data, _len);
while(_len >= 4)
{
uint32_t kk = *(uint32_t*)data;
mmix(m_hash, kk);
data += 4;
_len -= 4;
}
mixTail(data, _len);
}
void addUnaligned(const void* _data, int _len)
{
const uint8_t* data = (const uint8_t*)_data;
m_size += _len;
mixTail(data, _len);
while(_len >= 4)
{
uint32_t kk;
readUnaligned(data, kk);
mmix(m_hash, kk);
data += 4;
_len -= 4;
}
mixTail(data, _len);
}
///
void addUnaligned(const void* _data, int _len);
///
template<typename Ty>
void add(Ty _value)
{
add(&_value, sizeof(Ty) );
}
void add(Ty _value);
uint32_t end()
{
mmix(m_hash, m_tail);
mmix(m_hash, m_size);
m_hash ^= m_hash >> 13;
m_hash *= MURMUR_M;
m_hash ^= m_hash >> 15;
return m_hash;
}
///
uint32_t end();
private:
static void readUnaligned(const void* _data, uint32_t& _out)
{
const uint8_t* data = (const uint8_t*)_data;
if (BX_ENABLED(BX_CPU_ENDIAN_BIG) )
{
_out = 0
| data[0]<<24
| data[1]<<16
| data[2]<<8
| data[3]
;
}
else
{
_out = 0
| data[0]
| data[1]<<8
| data[2]<<16
| data[3]<<24
;
}
}
///
static void readUnaligned(const void* _data, uint32_t& _out);
void mixTail(const uint8_t*& _data, int& _len)
{
while( _len && ((_len<4) || m_count) )
{
m_tail |= (*_data++) << (m_count * 8);
m_count++;
_len--;
if(m_count == 4)
{
mmix(m_hash, m_tail);
m_tail = 0;
m_count = 0;
}
}
}
///
void mixTail(const uint8_t*& _data, int& _len);
uint32_t m_hash;
uint32_t m_tail;
@@ -146,25 +48,15 @@ namespace bx
uint32_t m_size;
};
#undef MURMUR_M
#undef MURMUR_R
#undef mmix
inline uint32_t hashMurmur2A(const void* _data, uint32_t _size)
{
HashMurmur2A murmur;
murmur.begin();
murmur.add(_data, (int)_size);
return murmur.end();
}
///
uint32_t hashMurmur2A(const void* _data, uint32_t _size);
///
template <typename Ty>
inline uint32_t hashMurmur2A(const Ty& _data)
{
BX_STATIC_ASSERT(BX_TYPE_IS_POD(Ty) );
return hashMurmur2A(&_data, sizeof(Ty) );
}
uint32_t hashMurmur2A(const Ty& _data);
} // namespace bx
#include "hash.inl"
#endif // BX_HASH_H_HEADER_GUARD

154
include/bx/hash.inl Normal file
View File

@@ -0,0 +1,154 @@
/*
* Copyright 2010-2017 Branimir Karadzic. All rights reserved.
* License: https://github.com/bkaradzic/bx#license-bsd-2-clause
*/
#ifndef BX_HASH_H_HEADER_GUARD
# error "Must be included from bx/hash.h!"
#endif // BX_HASH_H_HEADER_GUARD
namespace bx
{
#define MURMUR_M 0x5bd1e995
#define MURMUR_R 24
#define mmix(_h, _k) { _k *= MURMUR_M; _k ^= _k >> MURMUR_R; _k *= MURMUR_M; _h *= MURMUR_M; _h ^= _k; }
inline void HashMurmur2A::begin(uint32_t _seed)
{
m_hash = _seed;
m_tail = 0;
m_count = 0;
m_size = 0;
}
inline void HashMurmur2A::add(const void* _data, int _len)
{
if (BX_UNLIKELY(!isAligned(_data, 4) ) )
{
addUnaligned(_data, _len);
return;
}
addAligned(_data, _len);
}
inline void HashMurmur2A::addAligned(const void* _data, int _len)
{
const uint8_t* data = (const uint8_t*)_data;
m_size += _len;
mixTail(data, _len);
while(_len >= 4)
{
uint32_t kk = *(uint32_t*)data;
mmix(m_hash, kk);
data += 4;
_len -= 4;
}
mixTail(data, _len);
}
inline void HashMurmur2A::addUnaligned(const void* _data, int _len)
{
const uint8_t* data = (const uint8_t*)_data;
m_size += _len;
mixTail(data, _len);
while(_len >= 4)
{
uint32_t kk;
readUnaligned(data, kk);
mmix(m_hash, kk);
data += 4;
_len -= 4;
}
mixTail(data, _len);
}
template<typename Ty>
inline void HashMurmur2A::add(Ty _value)
{
add(&_value, sizeof(Ty) );
}
inline uint32_t HashMurmur2A::end()
{
mmix(m_hash, m_tail);
mmix(m_hash, m_size);
m_hash ^= m_hash >> 13;
m_hash *= MURMUR_M;
m_hash ^= m_hash >> 15;
return m_hash;
}
inline void HashMurmur2A::readUnaligned(const void* _data, uint32_t& _out)
{
const uint8_t* data = (const uint8_t*)_data;
if (BX_ENABLED(BX_CPU_ENDIAN_BIG) )
{
_out = 0
| data[0]<<24
| data[1]<<16
| data[2]<<8
| data[3]
;
}
else
{
_out = 0
| data[0]
| data[1]<<8
| data[2]<<16
| data[3]<<24
;
}
}
inline void HashMurmur2A::mixTail(const uint8_t*& _data, int& _len)
{
while( _len && ((_len<4) || m_count) )
{
m_tail |= (*_data++) << (m_count * 8);
m_count++;
_len--;
if(m_count == 4)
{
mmix(m_hash, m_tail);
m_tail = 0;
m_count = 0;
}
}
}
#undef MURMUR_M
#undef MURMUR_R
#undef mmix
inline uint32_t hashMurmur2A(const void* _data, uint32_t _size)
{
HashMurmur2A murmur;
murmur.begin();
murmur.add(_data, (int)_size);
return murmur.end();
}
template <typename Ty>
inline uint32_t hashMurmur2A(const Ty& _data)
{
BX_STATIC_ASSERT(BX_TYPE_IS_POD(Ty) );
return hashMurmur2A(&_data, sizeof(Ty) );
}
} // namespace bx