--- /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
#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)
{
"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)
#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)
{
/* 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);
/*
* 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__ */
projects / linux-platform-drivers-x86.git / commitdiff