mem.h
372 lines
| 11.3 KiB
| text/x-c
|
CLexer
|
r30434 | /** | ||
* Copyright (c) 2016-present, Yann Collet, Facebook, Inc. | ||||
* All rights reserved. | ||||
* | ||||
* This source code is licensed under the BSD-style license found in the | ||||
* LICENSE file in the root directory of this source tree. An additional grant | ||||
* of patent rights can be found in the PATENTS file in the same directory. | ||||
*/ | ||||
#ifndef MEM_H_MODULE | ||||
#define MEM_H_MODULE | ||||
#if defined (__cplusplus) | ||||
extern "C" { | ||||
#endif | ||||
/*-**************************************** | ||||
* Dependencies | ||||
******************************************/ | ||||
#include <stddef.h> /* size_t, ptrdiff_t */ | ||||
#include <string.h> /* memcpy */ | ||||
/*-**************************************** | ||||
* Compiler specifics | ||||
******************************************/ | ||||
#if defined(_MSC_VER) /* Visual Studio */ | ||||
# include <stdlib.h> /* _byteswap_ulong */ | ||||
# include <intrin.h> /* _byteswap_* */ | ||||
#endif | ||||
#if defined(__GNUC__) | ||||
# define MEM_STATIC static __inline __attribute__((unused)) | ||||
#elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) | ||||
# define MEM_STATIC static inline | ||||
#elif defined(_MSC_VER) | ||||
# define MEM_STATIC static __inline | ||||
#else | ||||
# define MEM_STATIC static /* this version may generate warnings for unused static functions; disable the relevant warning */ | ||||
#endif | ||||
/* code only tested on 32 and 64 bits systems */ | ||||
#define MEM_STATIC_ASSERT(c) { enum { XXH_static_assert = 1/(int)(!!(c)) }; } | ||||
MEM_STATIC void MEM_check(void) { MEM_STATIC_ASSERT((sizeof(size_t)==4) || (sizeof(size_t)==8)); } | ||||
/*-************************************************************** | ||||
* Basic Types | ||||
*****************************************************************/ | ||||
#if !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) ) | ||||
# include <stdint.h> | ||||
typedef uint8_t BYTE; | ||||
typedef uint16_t U16; | ||||
typedef int16_t S16; | ||||
typedef uint32_t U32; | ||||
typedef int32_t S32; | ||||
typedef uint64_t U64; | ||||
typedef int64_t S64; | ||||
|
r30822 | typedef intptr_t iPtrDiff; | ||
|
r30434 | #else | ||
|
r30822 | typedef unsigned char BYTE; | ||
|
r30434 | typedef unsigned short U16; | ||
typedef signed short S16; | ||||
typedef unsigned int U32; | ||||
typedef signed int S32; | ||||
typedef unsigned long long U64; | ||||
typedef signed long long S64; | ||||
|
r30822 | typedef ptrdiff_t iPtrDiff; | ||
|
r30434 | #endif | ||
/*-************************************************************** | ||||
* Memory I/O | ||||
*****************************************************************/ | ||||
/* MEM_FORCE_MEMORY_ACCESS : | ||||
* By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. | ||||
* Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. | ||||
* The below switch allow to select different access method for improved performance. | ||||
* Method 0 (default) : use `memcpy()`. Safe and portable. | ||||
* Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). | ||||
* This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. | ||||
* Method 2 : direct access. This method is portable but violate C standard. | ||||
* It can generate buggy code on targets depending on alignment. | ||||
* In some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) | ||||
* See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. | ||||
* Prefer these methods in priority order (0 > 1 > 2) | ||||
*/ | ||||
#ifndef MEM_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */ | ||||
# if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) | ||||
# define MEM_FORCE_MEMORY_ACCESS 2 | ||||
# elif defined(__INTEL_COMPILER) /*|| defined(_MSC_VER)*/ || \ | ||||
(defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) )) | ||||
# define MEM_FORCE_MEMORY_ACCESS 1 | ||||
# endif | ||||
#endif | ||||
MEM_STATIC unsigned MEM_32bits(void) { return sizeof(size_t)==4; } | ||||
MEM_STATIC unsigned MEM_64bits(void) { return sizeof(size_t)==8; } | ||||
MEM_STATIC unsigned MEM_isLittleEndian(void) | ||||
{ | ||||
const union { U32 u; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ | ||||
return one.c[0]; | ||||
} | ||||
#if defined(MEM_FORCE_MEMORY_ACCESS) && (MEM_FORCE_MEMORY_ACCESS==2) | ||||
/* violates C standard, by lying on structure alignment. | ||||
Only use if no other choice to achieve best performance on target platform */ | ||||
MEM_STATIC U16 MEM_read16(const void* memPtr) { return *(const U16*) memPtr; } | ||||
MEM_STATIC U32 MEM_read32(const void* memPtr) { return *(const U32*) memPtr; } | ||||
MEM_STATIC U64 MEM_read64(const void* memPtr) { return *(const U64*) memPtr; } | ||||
MEM_STATIC U64 MEM_readST(const void* memPtr) { return *(const size_t*) memPtr; } | ||||
MEM_STATIC void MEM_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; } | ||||
MEM_STATIC void MEM_write32(void* memPtr, U32 value) { *(U32*)memPtr = value; } | ||||
MEM_STATIC void MEM_write64(void* memPtr, U64 value) { *(U64*)memPtr = value; } | ||||
#elif defined(MEM_FORCE_MEMORY_ACCESS) && (MEM_FORCE_MEMORY_ACCESS==1) | ||||
/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ | ||||
/* currently only defined for gcc and icc */ | ||||
#if defined(_MSC_VER) || (defined(__INTEL_COMPILER) && defined(WIN32)) | ||||
__pragma( pack(push, 1) ) | ||||
typedef union { U16 u16; U32 u32; U64 u64; size_t st; } unalign; | ||||
__pragma( pack(pop) ) | ||||
#else | ||||
typedef union { U16 u16; U32 u32; U64 u64; size_t st; } __attribute__((packed)) unalign; | ||||
#endif | ||||
MEM_STATIC U16 MEM_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } | ||||
MEM_STATIC U32 MEM_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } | ||||
MEM_STATIC U64 MEM_read64(const void* ptr) { return ((const unalign*)ptr)->u64; } | ||||
MEM_STATIC U64 MEM_readST(const void* ptr) { return ((const unalign*)ptr)->st; } | ||||
MEM_STATIC void MEM_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; } | ||||
MEM_STATIC void MEM_write32(void* memPtr, U32 value) { ((unalign*)memPtr)->u32 = value; } | ||||
MEM_STATIC void MEM_write64(void* memPtr, U64 value) { ((unalign*)memPtr)->u64 = value; } | ||||
#else | ||||
/* default method, safe and standard. | ||||
can sometimes prove slower */ | ||||
MEM_STATIC U16 MEM_read16(const void* memPtr) | ||||
{ | ||||
U16 val; memcpy(&val, memPtr, sizeof(val)); return val; | ||||
} | ||||
MEM_STATIC U32 MEM_read32(const void* memPtr) | ||||
{ | ||||
U32 val; memcpy(&val, memPtr, sizeof(val)); return val; | ||||
} | ||||
MEM_STATIC U64 MEM_read64(const void* memPtr) | ||||
{ | ||||
U64 val; memcpy(&val, memPtr, sizeof(val)); return val; | ||||
} | ||||
MEM_STATIC size_t MEM_readST(const void* memPtr) | ||||
{ | ||||
size_t val; memcpy(&val, memPtr, sizeof(val)); return val; | ||||
} | ||||
MEM_STATIC void MEM_write16(void* memPtr, U16 value) | ||||
{ | ||||
memcpy(memPtr, &value, sizeof(value)); | ||||
} | ||||
MEM_STATIC void MEM_write32(void* memPtr, U32 value) | ||||
{ | ||||
memcpy(memPtr, &value, sizeof(value)); | ||||
} | ||||
MEM_STATIC void MEM_write64(void* memPtr, U64 value) | ||||
{ | ||||
memcpy(memPtr, &value, sizeof(value)); | ||||
} | ||||
#endif /* MEM_FORCE_MEMORY_ACCESS */ | ||||
MEM_STATIC U32 MEM_swap32(U32 in) | ||||
{ | ||||
#if defined(_MSC_VER) /* Visual Studio */ | ||||
return _byteswap_ulong(in); | ||||
#elif defined (__GNUC__) | ||||
return __builtin_bswap32(in); | ||||
#else | ||||
return ((in << 24) & 0xff000000 ) | | ||||
((in << 8) & 0x00ff0000 ) | | ||||
((in >> 8) & 0x0000ff00 ) | | ||||
((in >> 24) & 0x000000ff ); | ||||
#endif | ||||
} | ||||
MEM_STATIC U64 MEM_swap64(U64 in) | ||||
{ | ||||
#if defined(_MSC_VER) /* Visual Studio */ | ||||
return _byteswap_uint64(in); | ||||
#elif defined (__GNUC__) | ||||
return __builtin_bswap64(in); | ||||
#else | ||||
return ((in << 56) & 0xff00000000000000ULL) | | ||||
((in << 40) & 0x00ff000000000000ULL) | | ||||
((in << 24) & 0x0000ff0000000000ULL) | | ||||
((in << 8) & 0x000000ff00000000ULL) | | ||||
((in >> 8) & 0x00000000ff000000ULL) | | ||||
((in >> 24) & 0x0000000000ff0000ULL) | | ||||
((in >> 40) & 0x000000000000ff00ULL) | | ||||
((in >> 56) & 0x00000000000000ffULL); | ||||
#endif | ||||
} | ||||
MEM_STATIC size_t MEM_swapST(size_t in) | ||||
{ | ||||
if (MEM_32bits()) | ||||
return (size_t)MEM_swap32((U32)in); | ||||
else | ||||
return (size_t)MEM_swap64((U64)in); | ||||
} | ||||
/*=== Little endian r/w ===*/ | ||||
MEM_STATIC U16 MEM_readLE16(const void* memPtr) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
return MEM_read16(memPtr); | ||||
else { | ||||
const BYTE* p = (const BYTE*)memPtr; | ||||
return (U16)(p[0] + (p[1]<<8)); | ||||
} | ||||
} | ||||
MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val) | ||||
{ | ||||
if (MEM_isLittleEndian()) { | ||||
MEM_write16(memPtr, val); | ||||
} else { | ||||
BYTE* p = (BYTE*)memPtr; | ||||
p[0] = (BYTE)val; | ||||
p[1] = (BYTE)(val>>8); | ||||
} | ||||
} | ||||
MEM_STATIC U32 MEM_readLE24(const void* memPtr) | ||||
{ | ||||
return MEM_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16); | ||||
} | ||||
MEM_STATIC void MEM_writeLE24(void* memPtr, U32 val) | ||||
{ | ||||
MEM_writeLE16(memPtr, (U16)val); | ||||
((BYTE*)memPtr)[2] = (BYTE)(val>>16); | ||||
} | ||||
MEM_STATIC U32 MEM_readLE32(const void* memPtr) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
return MEM_read32(memPtr); | ||||
else | ||||
return MEM_swap32(MEM_read32(memPtr)); | ||||
} | ||||
MEM_STATIC void MEM_writeLE32(void* memPtr, U32 val32) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
MEM_write32(memPtr, val32); | ||||
else | ||||
MEM_write32(memPtr, MEM_swap32(val32)); | ||||
} | ||||
MEM_STATIC U64 MEM_readLE64(const void* memPtr) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
return MEM_read64(memPtr); | ||||
else | ||||
return MEM_swap64(MEM_read64(memPtr)); | ||||
} | ||||
MEM_STATIC void MEM_writeLE64(void* memPtr, U64 val64) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
MEM_write64(memPtr, val64); | ||||
else | ||||
MEM_write64(memPtr, MEM_swap64(val64)); | ||||
} | ||||
MEM_STATIC size_t MEM_readLEST(const void* memPtr) | ||||
{ | ||||
if (MEM_32bits()) | ||||
return (size_t)MEM_readLE32(memPtr); | ||||
else | ||||
return (size_t)MEM_readLE64(memPtr); | ||||
} | ||||
MEM_STATIC void MEM_writeLEST(void* memPtr, size_t val) | ||||
{ | ||||
if (MEM_32bits()) | ||||
MEM_writeLE32(memPtr, (U32)val); | ||||
else | ||||
MEM_writeLE64(memPtr, (U64)val); | ||||
} | ||||
/*=== Big endian r/w ===*/ | ||||
MEM_STATIC U32 MEM_readBE32(const void* memPtr) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
return MEM_swap32(MEM_read32(memPtr)); | ||||
else | ||||
return MEM_read32(memPtr); | ||||
} | ||||
MEM_STATIC void MEM_writeBE32(void* memPtr, U32 val32) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
MEM_write32(memPtr, MEM_swap32(val32)); | ||||
else | ||||
MEM_write32(memPtr, val32); | ||||
} | ||||
MEM_STATIC U64 MEM_readBE64(const void* memPtr) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
return MEM_swap64(MEM_read64(memPtr)); | ||||
else | ||||
return MEM_read64(memPtr); | ||||
} | ||||
MEM_STATIC void MEM_writeBE64(void* memPtr, U64 val64) | ||||
{ | ||||
if (MEM_isLittleEndian()) | ||||
MEM_write64(memPtr, MEM_swap64(val64)); | ||||
else | ||||
MEM_write64(memPtr, val64); | ||||
} | ||||
MEM_STATIC size_t MEM_readBEST(const void* memPtr) | ||||
{ | ||||
if (MEM_32bits()) | ||||
return (size_t)MEM_readBE32(memPtr); | ||||
else | ||||
return (size_t)MEM_readBE64(memPtr); | ||||
} | ||||
MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val) | ||||
{ | ||||
if (MEM_32bits()) | ||||
MEM_writeBE32(memPtr, (U32)val); | ||||
else | ||||
MEM_writeBE64(memPtr, (U64)val); | ||||
} | ||||
/* function safe only for comparisons */ | ||||
MEM_STATIC U32 MEM_readMINMATCH(const void* memPtr, U32 length) | ||||
{ | ||||
switch (length) | ||||
{ | ||||
default : | ||||
case 4 : return MEM_read32(memPtr); | ||||
case 3 : if (MEM_isLittleEndian()) | ||||
return MEM_read32(memPtr)<<8; | ||||
else | ||||
return MEM_read32(memPtr)>>8; | ||||
} | ||||
} | ||||
#if defined (__cplusplus) | ||||
} | ||||
#endif | ||||
#endif /* MEM_H_MODULE */ | ||||