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Diffstat (limited to 'include/asm-i386/string.h')
| -rw-r--r-- | include/asm-i386/string.h | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/include/asm-i386/string.h b/include/asm-i386/string.h new file mode 100644 index 00000000000..1679983d053 --- /dev/null +++ b/include/asm-i386/string.h @@ -0,0 +1,449 @@ +#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. + */ + +/* AK: in fact I bet it would be better to move this stuff all out of line. + */ + +#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 + +#define __HAVE_ARCH_MEMMOVE +void *memmove(void * dest,const void * src, size_t n); + +#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 |