leveldb/port/port_posix.h
costan ea175e28f8 Implement support for Intel crc32 instruction (SSE 4.2)
This change authored by vadimskipin and submitted via:

    https://github.com/google/leveldb/pull/309

Changes made to support iOS builds and other architectures
without support for SSE 4.2.

db_bench reports original crc32 speed at:

    crc32c : 3.610 micros/op; 1082.0 MB/s (4K per op)

with this change performance has increased to:

    crc32c : 0.843 micros/op; 4633.6 MB/s (4K per op)

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148694935
2017-02-28 14:08:46 -08:00

157 lines
4.1 KiB
C++

// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
//
// See port_example.h for documentation for the following types/functions.
#ifndef STORAGE_LEVELDB_PORT_PORT_POSIX_H_
#define STORAGE_LEVELDB_PORT_PORT_POSIX_H_
#undef PLATFORM_IS_LITTLE_ENDIAN
#if defined(OS_MACOSX)
#include <machine/endian.h>
#if defined(__DARWIN_LITTLE_ENDIAN) && defined(__DARWIN_BYTE_ORDER)
#define PLATFORM_IS_LITTLE_ENDIAN \
(__DARWIN_BYTE_ORDER == __DARWIN_LITTLE_ENDIAN)
#endif
#elif defined(OS_SOLARIS)
#include <sys/isa_defs.h>
#ifdef _LITTLE_ENDIAN
#define PLATFORM_IS_LITTLE_ENDIAN true
#else
#define PLATFORM_IS_LITTLE_ENDIAN false
#endif
#elif defined(OS_FREEBSD) || defined(OS_OPENBSD) ||\
defined(OS_NETBSD) || defined(OS_DRAGONFLYBSD)
#include <sys/types.h>
#include <sys/endian.h>
#define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
#elif defined(OS_HPUX)
#define PLATFORM_IS_LITTLE_ENDIAN false
#elif defined(OS_ANDROID)
// Due to a bug in the NDK x86 <sys/endian.h> definition,
// _BYTE_ORDER must be used instead of __BYTE_ORDER on Android.
// See http://code.google.com/p/android/issues/detail?id=39824
#include <endian.h>
#define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
#else
#include <endian.h>
#endif
#include <pthread.h>
#ifdef SNAPPY
#include <snappy.h>
#endif
#include <stdint.h>
#include <string>
#include "port/atomic_pointer.h"
#ifndef PLATFORM_IS_LITTLE_ENDIAN
#define PLATFORM_IS_LITTLE_ENDIAN (__BYTE_ORDER == __LITTLE_ENDIAN)
#endif
#if defined(OS_MACOSX) || defined(OS_SOLARIS) || defined(OS_FREEBSD) ||\
defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD) ||\
defined(OS_ANDROID) || defined(OS_HPUX) || defined(CYGWIN)
// Use fread/fwrite/fflush on platforms without _unlocked variants
#define fread_unlocked fread
#define fwrite_unlocked fwrite
#define fflush_unlocked fflush
#endif
#if defined(OS_MACOSX) || defined(OS_FREEBSD) ||\
defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD)
// Use fsync() on platforms without fdatasync()
#define fdatasync fsync
#endif
#if defined(OS_ANDROID) && __ANDROID_API__ < 9
// fdatasync() was only introduced in API level 9 on Android. Use fsync()
// when targetting older platforms.
#define fdatasync fsync
#endif
namespace leveldb {
namespace port {
static const bool kLittleEndian = PLATFORM_IS_LITTLE_ENDIAN;
#undef PLATFORM_IS_LITTLE_ENDIAN
class CondVar;
class Mutex {
public:
Mutex();
~Mutex();
void Lock();
void Unlock();
void AssertHeld() { }
private:
friend class CondVar;
pthread_mutex_t mu_;
// No copying
Mutex(const Mutex&);
void operator=(const Mutex&);
};
class CondVar {
public:
explicit CondVar(Mutex* mu);
~CondVar();
void Wait();
void Signal();
void SignalAll();
private:
pthread_cond_t cv_;
Mutex* mu_;
};
typedef pthread_once_t OnceType;
#define LEVELDB_ONCE_INIT PTHREAD_ONCE_INIT
extern void InitOnce(OnceType* once, void (*initializer)());
inline bool Snappy_Compress(const char* input, size_t length,
::std::string* output) {
#ifdef SNAPPY
output->resize(snappy::MaxCompressedLength(length));
size_t outlen;
snappy::RawCompress(input, length, &(*output)[0], &outlen);
output->resize(outlen);
return true;
#endif
return false;
}
inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
size_t* result) {
#ifdef SNAPPY
return snappy::GetUncompressedLength(input, length, result);
#else
return false;
#endif
}
inline bool Snappy_Uncompress(const char* input, size_t length,
char* output) {
#ifdef SNAPPY
return snappy::RawUncompress(input, length, output);
#else
return false;
#endif
}
inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
return false;
}
uint32_t AcceleratedCRC32C(uint32_t crc, const char* buf, size_t size);
} // namespace port
} // namespace leveldb
#endif // STORAGE_LEVELDB_PORT_PORT_POSIX_H_