rt-thread/bsp/gkipc/libraries/drv/gnu_c/memcpy.c

458 lines
16 KiB
C

/*
********************************************************************************
**
** \file ./boot/startup/src/memcpy.c
**
** \version $Id: memcpy.c 7112 2011-08-15 15:24:45Z dkless $
**
** \brief ARM1176 function retargeting.
**
** This files implements an optimized memcpy().
**
** \attention THIS SAMPLE CODE IS PROVIDED AS IS. FUJITSU SEMICONDUCTOR
** ACCEPTS NO RESPONSIBILITY OR LIABILITY FOR ANY ERRORS OR
** OMMISSIONS.
**
** (C) Copyright 2006-2010 by Fujitsu Microelectronics Europe GmbH
**
*****************************************************************************
*/
/********************************************************************
** File: memcpy.c
**
** Copyright (C) 1999-2010 Daniel Vik
**
** This software is provided 'as-is', without any express or implied
** warranty. In no event will the authors be held liable for any
** damages arising from the use of this software.
** Permission is granted to anyone to use this software for any
** purpose, including commercial applications, and to alter it and
** redistribute it freely, subject to the following restrictions:
**
** 1. The origin of this software must not be misrepresented; you
** must not claim that you wrote the original software. If you
** use this software in a product, an acknowledgment in the
** product documentation would be appreciated but is not
** required.
**
** 2. Altered source versions must be plainly marked as such, and
** must not be misrepresented as being the original software.
**
** 3. This notice may not be removed or altered from any source
** distribution.
**
**
** Description: Implementation of the standard library function memcpy.
** This implementation of memcpy() is ANSI-C89 compatible.
**
** The following configuration options can be set:
**
** LITTLE_ENDIAN - Uses processor with little endian
** addressing. Default is big endian.
**
** PRE_INC_PTRS - Use pre increment of pointers.
** Default is post increment of
** pointers.
**
** INDEXED_COPY - Copying data using array indexing.
** Using this option, disables the
** PRE_INC_PTRS option.
**
** MEMCPY_64BIT - Compiles memcpy for 64 bit
** architectures
**
**
** Best Settings:
**
** Intel x86: LITTLE_ENDIAN and INDEXED_COPY
**
*******************************************************************/
/*lint -save -e* */
/********************************************************************
** Configuration definitions.
*******************************************************************/
#define LITTLE_ENDIAN
#define INDEXED_COPY
#define MEMCPY_64BIT
/********************************************************************
** Includes for size_t definition
*******************************************************************/
#include <stddef.h>
#include <stdint.h>
/********************************************************************
** Typedefs
*******************************************************************/
/*lint -save -e751 */
typedef unsigned char UInt8;
typedef unsigned short UInt16;
typedef unsigned int UInt32;
#ifdef _WIN32
typedef unsigned __int64 UInt64;
#else
typedef unsigned long long UInt64;
#endif
#ifdef MEMCPY_64BIT
typedef UInt64 UIntN;
#define TYPE_WIDTH 8L
#else
typedef UInt32 UIntN;
#define TYPE_WIDTH 4L
#endif
/********************************************************************
** Remove definitions when INDEXED_COPY is defined.
*******************************************************************/
#if defined (INDEXED_COPY)
#if defined (PRE_INC_PTRS)
#undef PRE_INC_PTRS
#endif /*PRE_INC_PTRS*/
#endif /*INDEXED_COPY*/
/********************************************************************
** Definitions for pre and post increment of pointers.
*******************************************************************/
#if defined (PRE_INC_PTRS)
#define START_VAL(x) (x)--
#define INC_VAL(x) *++(x)
#define CAST_TO_U8(p, o) ((UInt8*)p + o + TYPE_WIDTH)
#define WHILE_DEST_BREAK (TYPE_WIDTH - 1)
#define PRE_LOOP_ADJUST - (TYPE_WIDTH - 1)
#define PRE_SWITCH_ADJUST + 1
#else /*PRE_INC_PTRS*/
#define START_VAL(x)
#define INC_VAL(x) *(x)++
#define CAST_TO_U8(p, o) ((UInt8*)p + o)
#define WHILE_DEST_BREAK 0
#define PRE_LOOP_ADJUST
#define PRE_SWITCH_ADJUST
#endif /*PRE_INC_PTRS*/
/********************************************************************
** Definitions for endians
*******************************************************************/
#if defined (LITTLE_ENDIAN)
#define SHL >>
#define SHR <<
#else /* LITTLE_ENDIAN */
#define SHL <<
#define SHR >>
#endif /* LITTLE_ENDIAN */
/********************************************************************
** Macros for copying words of different alignment.
** Uses incremening pointers.
*******************************************************************/
#define CP_INCR() { \
INC_VAL(dstN) = INC_VAL(srcN); \
}
#define CP_INCR_SH(shl, shr) { \
dstWord = srcWord SHL shl; \
srcWord = INC_VAL(srcN); \
dstWord |= srcWord SHR shr; \
INC_VAL(dstN) = dstWord; \
}
/********************************************************************
** Macros for copying words of different alignment.
** Uses array indexes.
*******************************************************************/
#define CP_INDEX(idx) { \
dstN[idx] = srcN[idx]; \
}
#define CP_INDEX_SH(x, shl, shr) { \
dstWord = srcWord SHL shl; \
srcWord = srcN[x]; \
dstWord |= srcWord SHR shr; \
dstN[x] = dstWord; \
}
/********************************************************************
** Macros for copying words of different alignment.
** Uses incremening pointers or array indexes depending on
** configuration.
*******************************************************************/
#if defined (INDEXED_COPY)
#define CP(idx) CP_INDEX(idx)
#define CP_SH(idx, shl, shr) CP_INDEX_SH(idx, shl, shr)
#define INC_INDEX(p, o) ((p) += (o))
#else /* INDEXED_COPY */
#define CP(idx) CP_INCR()
#define CP_SH(idx, shl, shr) CP_INCR_SH(shl, shr)
#define INC_INDEX(p, o)
#endif /* INDEXED_COPY */
#define COPY_REMAINING(count) { \
START_VAL(dst8); \
START_VAL(src8); \
\
switch (count) { \
case 7: INC_VAL(dst8) = INC_VAL(src8); \
case 6: INC_VAL(dst8) = INC_VAL(src8); \
case 5: INC_VAL(dst8) = INC_VAL(src8); \
case 4: INC_VAL(dst8) = INC_VAL(src8); \
case 3: INC_VAL(dst8) = INC_VAL(src8); \
case 2: INC_VAL(dst8) = INC_VAL(src8); \
case 1: INC_VAL(dst8) = INC_VAL(src8); \
case 0: \
default: break; \
} \
}
#define COPY_NO_SHIFT() { \
UIntN* dstN = (UIntN*)(dst8 PRE_LOOP_ADJUST); \
UIntN* srcN = (UIntN*)(src8 PRE_LOOP_ADJUST); \
size_t length = count / TYPE_WIDTH; \
\
while (length & 7) { \
CP_INCR(); \
length--; \
} \
\
length /= 8; \
\
while (length--) { \
CP(0); \
CP(1); \
CP(2); \
CP(3); \
CP(4); \
CP(5); \
CP(6); \
CP(7); \
\
INC_INDEX(dstN, 8); \
INC_INDEX(srcN, 8); \
} \
\
src8 = CAST_TO_U8(srcN, 0); \
dst8 = CAST_TO_U8(dstN, 0); \
\
COPY_REMAINING(count & (TYPE_WIDTH - 1)); \
\
return dest; \
}
#define COPY_SHIFT(shift) { \
UIntN* dstN = (UIntN*)(intptr_t)((((UIntN)(intptr_t)dst8) PRE_LOOP_ADJUST) & \
~(TYPE_WIDTH - 1)); \
UIntN* srcN = (UIntN*)(intptr_t)((((UIntN)(intptr_t)src8) PRE_LOOP_ADJUST) & \
~(TYPE_WIDTH - 1)); \
size_t length = count / TYPE_WIDTH; \
UIntN srcWord = INC_VAL(srcN); \
UIntN dstWord; \
\
while (length & 7) { \
CP_INCR_SH(8 * shift, 8 * (TYPE_WIDTH - shift)); \
length--; \
} \
\
length /= 8; \
\
while (length--) { \
CP_SH(0, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(1, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(2, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(3, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(4, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(5, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(6, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
CP_SH(7, 8 * shift, 8 * (TYPE_WIDTH - shift)); \
\
INC_INDEX(dstN, 8); \
INC_INDEX(srcN, 8); \
} \
\
src8 = CAST_TO_U8(srcN, (shift - TYPE_WIDTH)); \
dst8 = CAST_TO_U8(dstN, 0); \
\
COPY_REMAINING(count & (TYPE_WIDTH - 1)); \
\
return dest; \
}
/********************************************************************
**
** void *memcpy(void *dest, const void *src, size_t count)
**
** Args: dest - pointer to destination buffer
** src - pointer to source buffer
** count - number of bytes to copy
**
** Return: A pointer to destination buffer
**
** Purpose: Copies count bytes from src to dest.
** No overlap check is performed.
**
*******************************************************************/
#if 0//use libc 's api to improve performance.
void *memcpy(void *dest, const void *src, size_t count)
{
UInt8* dst8 = (UInt8*)dest;
UInt8* src8 = (UInt8*)src;
if (count < 8) {
COPY_REMAINING(count);
return dest;
}
START_VAL(dst8);
START_VAL(src8);
while (((UIntN)(intptr_t)dst8 & (TYPE_WIDTH - 1)) != WHILE_DEST_BREAK) {
INC_VAL(dst8) = INC_VAL(src8);
count--;
}
switch ((((UIntN)(intptr_t)src8) PRE_SWITCH_ADJUST) & (TYPE_WIDTH - 1)) {
case 0: COPY_NO_SHIFT();
case 1: COPY_SHIFT(1);
case 2: COPY_SHIFT(2);
case 3: COPY_SHIFT(3);
#if TYPE_WIDTH >= 4
case 4: COPY_SHIFT(4);
case 5: COPY_SHIFT(5);
case 6: COPY_SHIFT(6);
case 7: COPY_SHIFT(7);
#endif
}
return 0;
}
/**
* memset - Fill a region of memory with the given value
* @s: Pointer to the start of the area.
* @c: The byte to fill the area with
* @count: The size of the area.
*
* Do not use memset() to access IO space, use memset_io() instead.
*/
void * memset(void * s,int c,size_t count)
{
unsigned long *sl = (unsigned long *) s;
unsigned long cl = 0;
char *s8;
int i;
/* do it one word at a time (32 bits or 64 bits) while possible */
if ( ((unsigned long)s & (sizeof(*sl) - 1)) == 0) {
for (i = 0; i < sizeof(*sl); i++) {
cl <<= 8;
cl |= c & 0xff;
}
while (count >= sizeof(*sl)) {
*sl++ = cl;
count -= sizeof(*sl);
}
}
/* fill 8 bits at a time */
s8 = (char *)sl;
while (count--)
*s8++ = c;
return s;
}
/**
* memmove - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
*
* Unlike memcpy(), memmove() copes with overlapping areas.
*/
void * memmove(void * dest,const void *src,size_t count)
{
char *tmp, *s;
if (src == dest)
return dest;
if (dest <= src) {
tmp = (char *) dest;
s = (char *) src;
while (count--)
*tmp++ = *s++;
}
else {
tmp = (char *) dest + count;
s = (char *) src + count;
while (count--)
*--tmp = *--s;
}
return dest;
}
/**
* memcmp - Compare two areas of memory
* @cs: One area of memory
* @ct: Another area of memory
* @count: The size of the area.
*/
int memcmp(const void * cs,const void * ct,size_t count)
{
const unsigned char *su1, *su2;
int res = 0;
for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
if ((res = *su1 - *su2) != 0)
break;
return res;
}
#endif
/*lint -restore */