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#ifndef _I386_STRING_H_

#define _I386_STRING_H_

#ifdef __KERNEL__

#include <linux/config.h>

/*

 * On a 486 or Pentium, we are better off not using the

 * byte string operations. But on a 386 or a PPro the

 * byte string ops are faster than doing it by hand

 * (MUCH faster on a Pentium).

 */

/*

 * This string-include defines all string functions as inline

 * functions. Use gcc. It also assumes ds=es=data space, this should be

 * normal. Most of the string-functions are rather heavily hand-optimized,

 * see especially strsep,strstr,str[c]spn. They should work, but are not

 * very easy to understand. Everything is done entirely within the register

 * set, making the functions fast and clean. String instructions have been

 * used through-out, making for "slightly" unclear code :-)

 *

 *              NO Copyright (C) 1991, 1992 Linus Torvalds,

 *              consider these trivial functions to be PD.

 */

#define __HAVE_ARCH_STRCPY

static inline char * strcpy(char * dest,const char *src)

{

int d0, d1, d2;

__asm__ __volatile__(

        "1:\tlodsb\n\t"

        "stosb\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b"

        : "=&S" (d0), "=&D" (d1), "=&a" (d2)

        :"0" (src),"1" (dest) : "memory");

return dest;

}

#define __HAVE_ARCH_STRNCPY

static inline char * strncpy(char * dest,const char *src,size_t count)

{

int d0, d1, d2, d3;

__asm__ __volatile__(

        "1:\tdecl %2\n\t"

        "js 2f\n\t"

        "lodsb\n\t"

        "stosb\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b\n\t"

        "rep\n\t"

        "stosb\n"

        "2:"

        : "=&S" (d0), "=&D" (d1), "=&c" (d2), "=&a" (d3)

        :"0" (src),"1" (dest),"2" (count) : "memory");

return dest;

}

#define __HAVE_ARCH_STRCAT

static inline char * strcat(char * dest,const char * src)

{

int d0, d1, d2, d3;

__asm__ __volatile__(

        "repne\n\t"

        "scasb\n\t"

        "decl %1\n"

        "1:\tlodsb\n\t"

        "stosb\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b"

        : "=&S" (d0), "=&D" (d1), "=&a" (d2), "=&c" (d3)

        : "0" (src), "1" (dest), "2" (0), "3" (0xffffffffu):"memory");

return dest;

}

#define __HAVE_ARCH_STRNCAT

static inline char * strncat(char * dest,const char * src,size_t count)

{

int d0, d1, d2, d3;

__asm__ __volatile__(

        "repne\n\t"

        "scasb\n\t"

        "decl %1\n\t"

        "movl %8,%3\n"

        "1:\tdecl %3\n\t"

        "js 2f\n\t"

        "lodsb\n\t"

        "stosb\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b\n"

        "2:\txorl %2,%2\n\t"

        "stosb"

        : "=&S" (d0), "=&D" (d1), "=&a" (d2), "=&c" (d3)

        : "0" (src),"1" (dest),"2" (0),"3" (0xffffffffu), "g" (count)

        : "memory");

return dest;

}

#define __HAVE_ARCH_STRCMP

static inline int strcmp(const char * cs,const char * ct)

{

int d0, d1;

register int __res;

__asm__ __volatile__(

        "1:\tlodsb\n\t"

        "scasb\n\t"

        "jne 2f\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b\n\t"

        "xorl %%eax,%%eax\n\t"

        "jmp 3f\n"

        "2:\tsbbl %%eax,%%eax\n\t"

        "orb $1,%%al\n"

        "3:"

        :"=a" (__res), "=&S" (d0), "=&D" (d1)

                     :"1" (cs),"2" (ct));

return __res;

}

#define __HAVE_ARCH_STRNCMP

static inline int strncmp(const char * cs,const char * ct,size_t count)

{

register int __res;

int d0, d1, d2;

__asm__ __volatile__(

        "1:\tdecl %3\n\t"

        "js 2f\n\t"

        "lodsb\n\t"

        "scasb\n\t"

        "jne 3f\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b\n"

        "2:\txorl %%eax,%%eax\n\t"

        "jmp 4f\n"

        "3:\tsbbl %%eax,%%eax\n\t"

        "orb $1,%%al\n"

        "4:"

                     :"=a" (__res), "=&S" (d0), "=&D" (d1), "=&c" (d2)

                     :"1" (cs),"2" (ct),"3" (count));

return __res;

}

#define __HAVE_ARCH_STRCHR

static inline char * strchr(const char * s, int c)

{

int d0;

register char * __res;

__asm__ __volatile__(

        "movb %%al,%%ah\n"

        "1:\tlodsb\n\t"

        "cmpb %%ah,%%al\n\t"

        "je 2f\n\t"

        "testb %%al,%%al\n\t"

        "jne 1b\n\t"

        "movl $1,%1\n"

        "2:\tmovl %1,%0\n\t"

        "decl %0"

        :"=a" (__res), "=&S" (d0) : "1" (s),"0" (c));

return __res;

}

#define __HAVE_ARCH_STRRCHR

static inline char * strrchr(const char * s, int c)

{

int d0, d1;

register char * __res;

__asm__ __volatile__(

        "movb %%al,%%ah\n"

        "1:\tlodsb\n\t"

        "cmpb %%ah,%%al\n\t"

        "jne 2f\n\t"

        "leal -1(%%esi),%0\n"

        "2:\ttestb %%al,%%al\n\t"

        "jne 1b"

        :"=g" (__res), "=&S" (d0), "=&a" (d1) :"0" (0),"1" (s),"2" (c));

return __res;

}

#define __HAVE_ARCH_STRLEN

static inline size_t strlen(const char * s)

{

int d0;

register int __res;

__asm__ __volatile__(

        "repne\n\t"

        "scasb\n\t"

        "notl %0\n\t"

        "decl %0"

        :"=c" (__res), "=&D" (d0) :"1" (s),"a" (0), "0" (0xffffffffu));

return __res;

}

static inline void * __memcpy(void * to, const void * from, size_t n)

{

int d0, d1, d2;

__asm__ __volatile__(

        "rep ; movsl\n\t"

        "testb $2,%b4\n\t"

        "je 1f\n\t"

        "movsw\n"

        "1:\ttestb $1,%b4\n\t"

        "je 2f\n\t"

        "movsb\n"

        "2:"

        : "=&c" (d0), "=&D" (d1), "=&S" (d2)

        :"0" (n/4), "q" (n),"1" ((long) to),"2" ((long) from)

        : "memory");

return (to);

}

/*

 * This looks horribly ugly, but the compiler can optimize it totally,

 * as the count is constant.

 */

static inline void * __constant_memcpy(void * to, const void * from, size_t n)

{

        if (n <= 128)

                return __builtin_memcpy(to, from, n);

#define COMMON(x) \

__asm__ __volatile__( \

        "rep ; movsl" \

        x \

        : "=&c" (d0), "=&D" (d1), "=&S" (d2) \

        : "0" (n/4),"1" ((long) to),"2" ((long) from) \

        : "memory");

{

        int d0, d1, d2;

        switch (n % 4) {

                case 0: COMMON(""); return to;

                case 1: COMMON("\n\tmovsb"); return to;

                case 2: COMMON("\n\tmovsw"); return to;

                default: COMMON("\n\tmovsw\n\tmovsb"); return to;

        }

}

#undef COMMON

}

#define __HAVE_ARCH_MEMCPY

#ifdef CONFIG_X86_USE_3DNOW

#include <asm/mmx.h>

/*

 *      This CPU favours 3DNow strongly (eg AMD Athlon)

 */

static inline void * __constant_memcpy3d(void * to, const void * from, size_t len)

{

        if (len < 512)

                return __constant_memcpy(to, from, len);

        return _mmx_memcpy(to, from, len);

}

static __inline__ void *__memcpy3d(void *to, const void *from, size_t len)

{

        if (len < 512)

                return __memcpy(to, from, len);

        return _mmx_memcpy(to, from, len);

}

#define memcpy(t, f, n) \

(__builtin_constant_p(n) ? \

 __constant_memcpy3d((t),(f),(n)) : \

 __memcpy3d((t),(f),(n)))

#else

/*

 *      No 3D Now!

 */

#define memcpy(t, f, n) \

(__builtin_constant_p(n) ? \

 __constant_memcpy((t),(f),(n)) : \

 __memcpy((t),(f),(n)))

#endif

/*

 * struct_cpy(x,y), copy structure *x into (matching structure) *y.

 *

 * We get link-time errors if the structure sizes do not match.

 * There is no runtime overhead, it's all optimized away at

 * compile time.

 */

extern void __struct_cpy_bug (void);

#define struct_cpy(x,y)                         \

({                                              \

        if (sizeof(*(x)) != sizeof(*(y)))       \

                __struct_cpy_bug;               \

        memcpy(x, y, sizeof(*(x)));             \

})

#define __HAVE_ARCH_MEMMOVE

static inline void * memmove(void * dest,const void * src, size_t n)

{

int d0, d1, d2;

if (dest<src)

__asm__ __volatile__(

        "rep\n\t"

        "movsb"

        : "=&c" (d0), "=&S" (d1), "=&D" (d2)

        :"0" (n),"1" (src),"2" (dest)

        : "memory");

else

__asm__ __volatile__(

        "std\n\t"

        "rep\n\t"

        "movsb\n\t"

        "cld"

        : "=&c" (d0), "=&S" (d1), "=&D" (d2)

        :"0" (n),

         "1" (n-1+(const char *)src),

         "2" (n-1+(char *)dest)

        :"memory");

return dest;

}

#define memcmp __builtin_memcmp

#define __HAVE_ARCH_MEMCHR

static inline void * memchr(const void * cs,int c,size_t count)

{

int d0;

register void * __res;

if (!count)

        return NULL;

__asm__ __volatile__(

        "repne\n\t"

        "scasb\n\t"

        "je 1f\n\t"

        "movl $1,%0\n"

        "1:\tdecl %0"

        :"=D" (__res), "=&c" (d0) : "a" (c),"0" (cs),"1" (count));

return __res;

}

static inline void * __memset_generic(void * s, char c,size_t count)

{

int d0, d1;

__asm__ __volatile__(

        "rep\n\t"

        "stosb"

        : "=&c" (d0), "=&D" (d1)

        :"a" (c),"1" (s),"0" (count)

        :"memory");

return s;

}

/* we might want to write optimized versions of these later */

#define __constant_count_memset(s,c,count) __memset_generic((s),(c),(count))

/*

 * memset(x,0,y) is a reasonably common thing to do, so we want to fill

 * things 32 bits at a time even when we don't know the size of the

 * area at compile-time..

 */

static inline void * __constant_c_memset(void * s, unsigned long c, size_t count)

{

int d0, d1;

__asm__ __volatile__(

        "rep ; stosl\n\t"

        "testb $2,%b3\n\t"

        "je 1f\n\t"

        "stosw\n"

        "1:\ttestb $1,%b3\n\t"

        "je 2f\n\t"

        "stosb\n"

        "2:"

        : "=&c" (d0), "=&D" (d1)

        :"a" (c), "q" (count), "0" (count/4), "1" ((long) s)

        :"memory");

return (s);    

}

/* Added by Gertjan van Wingerde to make minix and sysv module work */

#define __HAVE_ARCH_STRNLEN

static inline size_t strnlen(const char * s, size_t count)

{

int d0;

register int __res;

__asm__ __volatile__(

        "movl %2,%0\n\t"

        "jmp 2f\n"

        "1:\tcmpb $0,(%0)\n\t"

        "je 3f\n\t"

        "incl %0\n"

        "2:\tdecl %1\n\t"

        "cmpl $-1,%1\n\t"

        "jne 1b\n"

        "3:\tsubl %2,%0"

        :"=a" (__res), "=&d" (d0)

        :"c" (s),"1" (count));

return __res;

}

/* end of additional stuff */

#define __HAVE_ARCH_STRSTR

extern char *strstr(const char *cs, const char *ct);

/*

 * This looks horribly ugly, but the compiler can optimize it totally,

 * as we by now know that both pattern and count is constant..

 */

static inline void * __constant_c_and_count_memset(void * s, unsigned long pattern, size_t count)

{

        switch (count) {

                case 0:

                        return s;

                case 1:

                        *(unsigned char *)s = pattern;

                        return s;

                case 2:

                        *(unsigned short *)s = pattern;

                        return s;

                case 3:

                        *(unsigned short *)s = pattern;

                        *(2+(unsigned char *)s) = pattern;

                        return s;

                case 4:

                        *(unsigned long *)s = pattern;

                        return s;

        }

#define COMMON(x) \

__asm__  __volatile__( \

        "rep ; stosl" \

        x \

        : "=&c" (d0), "=&D" (d1) \

        : "a" (pattern),"0" (count/4),"1" ((long) s) \

        : "memory")

{

        int d0, d1;

        switch (count % 4) {

                case 0: COMMON(""); return s;

                case 1: COMMON("\n\tstosb"); return s;

                case 2: COMMON("\n\tstosw"); return s;

                default: COMMON("\n\tstosw\n\tstosb"); return s;

        }

}

#undef COMMON

}

#define __constant_c_x_memset(s, c, count) \

(__builtin_constant_p(count) ? \

 __constant_c_and_count_memset((s),(c),(count)) : \

 __constant_c_memset((s),(c),(count)))

#define __memset(s, c, count) \

(__builtin_constant_p(count) ? \

 __constant_count_memset((s),(c),(count)) : \

 __memset_generic((s),(c),(count)))

#define __HAVE_ARCH_MEMSET

#define memset(s, c, count) \

(__builtin_constant_p(c) ? \

 __constant_c_x_memset((s),(0x01010101UL*(unsigned char)(c)),(count)) : \

 __memset((s),(c),(count)))

/*

 * find the first occurrence of byte 'c', or 1 past the area if none

 */

#define __HAVE_ARCH_MEMSCAN

static inline void * memscan(void * addr, int c, size_t size)

{

        if (!size)

                return addr;

        __asm__("repnz; scasb\n\t"

                "jnz 1f\n\t"

                "dec %%edi\n"

                "1:"

                : "=D" (addr), "=c" (size)

                : "0" (addr), "1" (size), "a" (c));

        return addr;

}

#endif /* __KERNEL__ */

#endif