diff options
| -rw-r--r-- | arch/i386/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/i386/lib/string.c | 257 | ||||
| -rw-r--r-- | include/asm-i386/string.h | 243 |
3 files changed, 271 insertions, 231 deletions
diff --git a/arch/i386/lib/Makefile b/arch/i386/lib/Makefile index 22d8ac5815f..4d105fdfe81 100644 --- a/arch/i386/lib/Makefile +++ b/arch/i386/lib/Makefile @@ -4,7 +4,7 @@ lib-y = checksum.o delay.o usercopy.o getuser.o putuser.o memcpy.o strstr.o \ - bitops.o semaphore.o + bitops.o semaphore.o string.o lib-$(CONFIG_X86_USE_3DNOW) += mmx.o diff --git a/arch/i386/lib/string.c b/arch/i386/lib/string.c new file mode 100644 index 00000000000..2c773fefa3d --- /dev/null +++ b/arch/i386/lib/string.c @@ -0,0 +1,257 @@ +/* + * 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 :-) + * + * AK: On P4 and K7 using non string instruction implementations might be faster + * for large memory blocks. But most of them are unlikely to be used on large + * strings. + */ + +#include <linux/string.h> +#include <linux/module.h> + +#ifdef __HAVE_ARCH_STRCPY +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; +} +EXPORT_SYMBOL(strcpy); +#endif + +#ifdef __HAVE_ARCH_STRNCPY +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; +} +EXPORT_SYMBOL(strncpy); +#endif + +#ifdef __HAVE_ARCH_STRCAT +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; +} +EXPORT_SYMBOL(strcat); +#endif + +#ifdef __HAVE_ARCH_STRNCAT +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; +} +EXPORT_SYMBOL(strncat); +#endif + +#ifdef __HAVE_ARCH_STRCMP +int strcmp(const char * cs,const char * ct) +{ + int d0, d1; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strcmp); +#endif + +#ifdef __HAVE_ARCH_STRNCMP +int strncmp(const char * cs,const char * ct,size_t count) +{ + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strncmp); +#endif + +#ifdef __HAVE_ARCH_STRCHR +char *strchr(const char * s, int c) +{ + int d0; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strchr); +#endif + +#ifdef __HAVE_ARCH_STRRCHR +char *strrchr(const char * s, int c) +{ + int d0, d1; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strrchr); +#endif + +#ifdef __HAVE_ARCH_STRLEN +size_t strlen(const char * s) +{ + int d0; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strlen); +#endif + +#ifdef __HAVE_ARCH_MEMCHR +void *memchr(const void *cs,int c,size_t count) +{ + int d0; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(memchr); +#endif + +#ifdef __HAVE_ARCH_MEMSCAN +void *memscan(void * addr, int c, size_t size) +{ + if (!size) + return addr; + asm volatile("repnz; scasb\n\t" + "jnz 1f\n\t" + "dec %%edi\n" + "1:" + : "=D" (addr), "=c" (size) + : "0" (addr), "1" (size), "a" (c) + : "memory"); + return addr; +} +EXPORT_SYMBOL(memscan); +#endif + +#ifdef __HAVE_ARCH_STRNLEN +size_t strnlen(const char *s, size_t count) +{ + int d0; + 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) + :"memory"); + return res; +} +EXPORT_SYMBOL(strnlen); +#endif diff --git a/include/asm-i386/string.h b/include/asm-i386/string.h index b9277361954..a9b64453bdf 100644 --- a/include/asm-i386/string.h +++ b/include/asm-i386/string.h @@ -2,203 +2,35 @@ #define _I386_STRING_H_ #ifdef __KERNEL__ -/* - * 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. - */ +/* Let gcc decide wether to inline or use the out of line functions */ #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; -} +extern char *strcpy(char *dest, const char *src); #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; -} +extern char *strncpy(char *dest, const char *src, size_t count); #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; -} +extern char *strcat(char *dest, const char *src); #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; -} +extern char *strncat(char *dest, const char *src, size_t count); #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) - :"memory"); -return __res; -} +extern int strcmp(const char *cs, const char *ct); #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) - :"memory"); -return __res; -} +extern int strncmp(const char *cs, const char *ct, size_t count); #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) - :"memory"); -return __res; -} +extern char *strchr(const char *s, int c); #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) - :"memory"); -return __res; -} +extern char *strrchr(const char *s, int c); #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) - :"memory"); -return __res; -} +extern size_t strlen(const char *s); static __always_inline void * __memcpy(void * to, const void * from, size_t n) { @@ -207,9 +39,7 @@ __asm__ __volatile__( "rep ; movsl\n\t" "movl %4,%%ecx\n\t" "andl $3,%%ecx\n\t" -#if 1 /* want to pay 2 byte penalty for a chance to skip microcoded rep? */ "jz 1f\n\t" -#endif "rep ; movsb\n\t" "1:" : "=&c" (d0), "=&D" (d1), "=&S" (d2) @@ -328,23 +158,7 @@ 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) - :"memory"); -return __res; -} +extern void *memchr(const void * cs,int c,size_t count); static inline void * __memset_generic(void * s, char c,size_t count) { @@ -386,29 +200,10 @@ 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) - :"memory"); -return __res; -} +extern size_t strnlen(const char * s, size_t count); /* end of additional stuff */ #define __HAVE_ARCH_STRSTR - extern char *strstr(const char *cs, const char *ct); /* @@ -474,19 +269,7 @@ __asm__ __volatile__( \ * 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) - : "memory"); - return addr; -} +extern void *memscan(void * addr, int c, size_t size); #endif /* __KERNEL__ */ |