+++ /dev/null
-/*
- * 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
git.openpandora.org / pandora-kernel.git / blobdiff