diff options
Diffstat (limited to 'sysdeps/i386/i486/bits')
| -rw-r--r-- | sysdeps/i386/i486/bits/string.h | 853 |
1 files changed, 853 insertions, 0 deletions
diff --git a/sysdeps/i386/i486/bits/string.h b/sysdeps/i386/i486/bits/string.h new file mode 100644 index 0000000000..f141bd50e1 --- /dev/null +++ b/sysdeps/i386/i486/bits/string.h @@ -0,0 +1,853 @@ +/* Optimized, inlined string functions. i486 version. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#ifndef _STRING_H +#error "Never use <bits/string.h> directly; include <string.h> instead." +#endif + +/* We only provide optimizations for the GNU CC. */ +#if defined __GNUC__ && __GNUC__ >= 2 + +#ifdef __cplusplus +# define __STRING_INLINE inline +#else +# define __STRING_INLINE extern __inline +#endif + + +/* Copy N bytes of SRC to DEST. */ +#define memcpy(dest, src, n) \ + (__extension__ (__builtin_constant_p (n) \ + ? __memcpy_c (dest, src, n) \ + : __memcpy_g (dest, src, n))) +#define __memcpy_c(dest, src, n) \ + (((n) % 4 == 0) \ + ? __memcpy_by4 (dest, src, n) \ + : (((n) % 2 == 0) \ + ? __memcpy_by2 (dest, src, n) \ + : __memcpy_g (dest, src, n))) + +__STRING_INLINE void * +__memcpy_by4 (void *__dest, __const void *__src, size_t __n) +{ + register void *__tmp = __dest; + register int __dummy1, __dummy2; + __asm__ __volatile__ + ("1:\n\t" + "movl (%2),%0\n\t" + "leal 4(%2),%2\n\t" + "movl %0,(%1)\n\t" + "leal 4(%1),%1\n\t" + "decl %3\n\t" + "jnz 1b" + : "=r" (__dummy1), "=r" (__tmp), "=r" (__src), "=r" (__dummy2) + : "1" (__tmp), "2" (__src), "3" (__n / 4) + : "memory", "cc"); + return __dest; +} + +__STRING_INLINE void * +__memcpy_by2 (void *__dest, __const void *__src, size_t __n) +{ + register void *__tmp = __dest; + register int __dummy1, __dummy2; + __asm__ __volatile__ + ("shrl $1,%3\n\t" + "jz 2f\n" /* only a word */ + "1:\n\t" + "movl (%2),%0\n\t" + "leal 4(%2),%2\n\t" + "movl %0,(%1)\n\t" + "leal 4(%1),%1\n\t" + "decl %3\n\t" + "jnz 1b\n" + "2:\n\t" + "movw (%2),%w0\n\t" + "movw %w0,(%1)" + : "=q" (__dummy1), "=r" (__tmp), "=r" (__src), "=r" (__dummy2) + : "1" (__tmp), "2" (__src), "3" (__n / 2) + : "memory", "cc"); + return __dest; +} + +__STRING_INLINE void * +__memcpy_g (void *__dest, __const void *__src, size_t __n) +{ + register void *__tmp = __dest; + __asm__ __volatile__ + ("cld\n\t" + "shrl $1,%%ecx\n\t" + "jnc 1f\n\t" + "movsb\n" + "1:\n\t" + "shrl $1,%%ecx\n\t" + "jnc 2f\n\t" + "movsw\n" + "2:\n\t" + "rep; movsl" + : /* no output */ + : "c" (__n), "D" (__tmp),"S" (__src) + : "cx", "di", "si", "memory", "cc"); + return __dest; +} + + +/* Copy N bytes of SRC to DEST, guaranteeing + correct behavior for overlapping strings. */ +__STRING_INLINE void * +memmove (void *__dest, __const void *__src, size_t __n) +{ + register void *__tmp = __dest; + if (__dest < __src) + __asm__ __volatile__ + ("cld\n\t" + "rep; movsb" + : /* no output */ + : "c" (__n), "S" (__src), "D" (__tmp) + : "cx", "si", "di"); + else + __asm__ __volatile__ + ("std\n\t" + "rep; movsb\n\t" + "cld" + : /* no output */ + : "c" (__n), "S" (__n - 1 + (__const char *) __src), + "D" (__n - 1 + (char *) __tmp) + : "cx", "si", "di", "memory"); + return __dest; +} + + +/* Compare N bytes of S1 and S2. */ +#ifndef __PIC__ +/* gcc has problems to spill registers when using PIC. */ +__STRING_INLINE int +memcmp (__const void *__s1, __const void *__s2, size_t __n) +{ + register int __res; + __asm__ __volatile__ + ("cld\n\t" + "repe; cmpsb\n\t" + "je 1f\n\t" + "sbbl %0,%0\n\t" + "orb $1,%b0\n" + "1:" + : "=a" (__res) + : "0" (0), "S" (__s1), "D" (__s2), "c" (__n) + : "si", "di", "cx", "cc"); + return __res; +} +#endif + + +/* Set N bytes of S to C. */ +#define memset(s, c, n) \ + (__extension__ (__builtin_constant_p (c) \ + ? (__builtin_constant_p (n) \ + ? __memset_cc (s, c, n) \ + : __memset_cg (s, c, n)) \ + : (__builtin_constant_p (n) \ + ? __memset_gc (s, c, n) \ + : __memset_gg (s, c, n)))) +#define __memset_cc(s, c, n) \ + (((n) % 4 == 0) \ + ? __memset_cc_by4 (s, c, n) \ + : (((n) % 2== 0) \ + ? __memset_cc_by2 (s, c, n) \ + : __memset_cg (s, c, n))) +#define __memset_gc(s, c, n) \ + (((n) % 4== 0) \ + ? __memset_gc_by4 (s, c, n) \ + : (((n) % 2 == 0) \ + ? __memset_gc_by2 (s, c, n) \ + : __memset_gg (s, c, n))) + +__STRING_INLINE void * +__memset_cc_by4 (void *__s, int __c, size_t __n) +{ + register char *__tmp = __s; + register int __dummy; + __asm__ __volatile__ + ("1:\n\t" + "movl %2,(%0)\n\t" + "leal 4(%0),%0\n\t" + "decl %1\n\t" + "jnz 1b" + : "=r" (__tmp), "=r" (__dummy) + : "q" (0x01010101UL * (unsigned char) __c), "0" (__tmp), "1" (__n / 4) + : "memory", "cc"); + return __s; +} + +__STRING_INLINE void * +__memset_cc_by2 (void *__s, char __c, size_t __n) +{ + register void *__tmp = __s; + register int __dummy; + __asm__ __volatile__ + ("shrl $1,%1\n\t" /* may be divisible also by 4 */ + "jz 2f\n" + "1:\n\t" + "movl %2,(%0)\n\t" + "leal 4(%0),%0\n\t" + "decl %1\n\t" + "jnz 1b\n" + "2:\n\t" + "movw %w2,(%0)" + : "=r" (__tmp), "=r" (__dummy) + : "q" (0x01010101UL * (unsigned char) __c), "0" (__tmp), "1" (__n / 2) + : "memory", "cc"); + return __s; +} + +__STRING_INLINE void * +__memset_gc_by4 (void *__s, char __c, size_t __n) +{ + register void *__tmp = __s; + register int __dummy; + __asm__ __volatile__ + ("movb %b0,%h0\n" + "pushw %w0\n\t" + "shll $16,%0\n\t" + "popw %w0\n" + "1:\n\t" + "movl %0,(%1)\n\t" + "addl $4,%1\n\t" + "decl %2\n\t" + "jnz 1b\n" + : "=q" (__c), "=r" (__tmp), "=r" (__dummy) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) + : "memory", "cc"); + return __s; +} + +__STRING_INLINE void * +__memset_gc_by2 (void *__s, char __c, size_t __n) +{ + register void *__tmp = __s; + register int __dummy1, __dummy2; + __asm__ __volatile__ + ("movb %b0,%h0\n\t" + "shrl $1,%2\n\t" /* may be divisible also by 4 */ + "jz 2f\n\t" + "pushw %w0\n\t" + "shll $16,%0\n\t" + "popw %w0\n" + "1:\n\t" + "movl %0,(%1)\n\t" + "leal 4(%1),%1\n\t" + "decl %2\n\t" + "jnz 1b\n" + "2:\n\t" + "movw %w0,(%1)" + : "=q" (__dummy1), "=r" (__tmp), "=r" (__dummy2) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 2) + : "memory", "cc"); + return __s; +} + +__STRING_INLINE void * +__memset_cg (void *__s, char __c, size_t __n) +{ + register void *__tmp = __s; + __asm__ __volatile__ + ("shrl $1,%%ecx\n\t" + "rep; stosw\n\t" + "jnc 1f\n\t" + "movb %%al,(%%edi)\n" + "1:" + : /* no output */ + : "c" (__n),"D" (__tmp), "a" (0x0101U * (unsigned char) __c) + : "cx", "di", "memory", "cc"); + return __s; +} + +__STRING_INLINE void * +__memset_gg (void *__s, char __c, size_t __n) +{ + register void *__tmp = __s; + __asm__ __volatile__ + ("movb %%al,%%ah\n\t" + "shrl $1,%%ecx\n\t" + "rep; stosw\n\t" + "jnc 1f\n\t" + "movb %%al,(%%edi)\n" + "1:" + : /* no output */ + : "c" (__n), "D" (__tmp), "a" (__c) + : "cx", "di", "memory", "cc"); + return __s; +} + + +/* Search N bytes of S for C. */ +__STRING_INLINE void * +memchr (__const void *__s, int __c, size_t __n) +{ + register void *__res; + if (__n == 0) + return NULL; + __asm__ __volatile__ + ("cld\n\t" + "repne; scasb\n\t" + "je 1f\n\t" + "movl $1,%0\n" + "1:\n\t" + "decl %0" + : "=D" (__res) + : "a" (__c), "D" (__s), "c" (__n) + : "cx", "cc"); + return __res; +} + + +/* Return the length of S. */ +__STRING_INLINE size_t +strlen (__const char *__str) +{ + register char __dummy; + register __const char *__tmp = __str; + __asm__ __volatile__ + ("1:\n\t" + "movb (%0),%1\n\t" + "leal 1(%0),%0\n\t" + "testb %1,%1\n\t" + "jne 1b" + : "=r" (__tmp), "=q" (__dummy) + : "0" (__str) + : "memory", "cc" ); + return __tmp - __str - 1; +} + + +/* Copy SRC to DEST. */ +__STRING_INLINE char * +strcpy (char *__dest, __const char *__src) +{ + register char *__tmp = __dest; + register char __dummy; + __asm__ __volatile__ + ( + "1:\n\t" + "movb (%0),%2\n\t" + "incl %0\n\t" + "movb %2,(%1)\n\t" + "incl %1\n\t" + "testb %2,%2\n\t" + "jne 1b" + : "=r" (__src), "=r" (__tmp), "=q" (__dummy) + : "0" (__src), "1" (__tmp) + : "memory", "cc"); + return __dest; +} + + +/* Copy no more than N characters of SRC to DEST. */ +__STRING_INLINE char * +strncpy (char *__dest, __const char *__src, size_t __n) +{ + register char *__tmp = __dest; + register char __dummy; + if (__n > 0) + __asm__ __volatile__ + ("1:\n\t" + "movb (%0),%2\n\t" + "incl %0\n\t" + "movb %2,(%1)\n\t" + "incl %1\n\t" + "decl %3\n\t" + "je 3f\n\t" + "testb %2,%2\n\t" + "jne 1b\n\t" + "2:\n\t" + "movb %2,(%1)\n\t" + "incl %1\n\t" + "decl %3\n\t" + "jne 2b\n\t" + "3:" + : "=r" (__src), "=r" (__tmp), "=q" (__dummy), "=r" (__n) + : "0" (__src), "1" (__tmp), "3" (__n) + : "memory", "cc"); + + return __dest; +} + + +/* Append SRC onto DEST. */ +__STRING_INLINE char * +strcat (char *__dest, __const char *__src) +{ + register char *__tmp = __dest - 1; + register char __dummy; + __asm__ __volatile__ + ( + "1:\n\t" + "incl %1\n\t" + "cmpb $0,(%1)\n\t" + "jne 1b\n" + "2:\n\t" + "movb (%2),%b0\n\t" + "incl %2\n\t" + "movb %b0,(%1)\n\t" + "incl %1\n\t" + "testb %b0,%b0\n\t" + "jne 2b\n" + : "=q" (__dummy), "=r" (__tmp), "=r" (__src) + : "1" (__tmp), "2" (__src) + : "memory", "cc"); + return __dest; +} + + +/* Append no more than N characters from SRC onto DEST. */ +__STRING_INLINE char * +strncat (char *__dest, __const char *__src, size_t __n) +{ + register char *__tmp = __dest - 1; + register char __dummy; + __asm__ __volatile__ + ( + "1:\n\t" + "incl %1\n\t" + "cmpb $0,(%1)\n\t" + "jne 1b\n" + "2:\n\t" + "decl %3\n\t" + "js 3f\n\t" + "movb (%2),%b0\n\t" + "leal 1(%2),%2\n\t" + "movb %b0,(%1)\n\t" + "leal 1(%1),%1\n\t" + "testb %b0,%b0\n\t" + "jne 2b\n" + "3:\n\t" + "movb $0,(%1)\n\t" + : "=q" (__dummy), "=r" (__tmp), "=r" (__src), "=r" (__n) + : "1" (__tmp), "2" (__src), "3" (__n) + : "memory", "cc"); + return __dest; +} + + +/* Compare S1 and S2. */ +__STRING_INLINE int +strcmp (__const char *__s1, __const char *__s2) +{ + register int __res; + __asm__ __volatile__ + ("1:\n\t" + "movb (%1),%b0\n\t" + "leal 1(%1),%1\n\t" + "cmpb %b0,(%2)\n\t" + "jne 2f\n\t" + "leal 1(%2),%2\n\t" + "testb %b0,%b0\n\t" + "jne 1b\n\t" + "xorl %0,%0\n\t" + "jmp 3f\n" + "2:\n\t" + "movl $1,%0\n\t" + "jb 3f\n\t" + "negl %0\n" + "3:" + : "=q" (__res), "=r" (__s1), "=r" (__s2) + : "1" (__s1), "2" (__s2) + : "cc"); + return __res; +} + + +/* Compare N characters of S1 and S2. */ +__STRING_INLINE int +strncmp (__const char *__s1, __const char *__s2, size_t __n) +{ + register int __res; + __asm__ __volatile__ + ("1:\n\t" + "decl %3\n\t" + "js 2f\n\t" + "movb (%1),%b0\n\t" + "incl %1\n\t" + "cmpb %b0,(%2)\n\t" + "jne 3f\n\t" + "incl %2\n\t" + "testb %b0,%b0\n\t" + "jne 1b\n" + "2:\n\t" + "xorl %0,%0\n\t" + "jmp 4f\n" + "3:\n\t" + "movl $1,%0\n\t" + "jb 4f\n\t" + "negl %0\n" + "4:" + : "=q" (__res), "=r" (__s1), "=r" (__s2), "=r" (__n) + : "1" (__s1), "2" (__s2), "3" (__n) + : "cc"); + return __res; +} + + +/* Find the first occurrence of C in S. */ +#define strchr(s, c) \ + (__extension__ (__builtin_constant_p (c) \ + ? __strchr_c (s, ((c) & 0xff) << 8) \ + : __strchr_g (s, c))) + +__STRING_INLINE char * +__strchr_g (__const char *__s, int __c) +{ + register char *__res; + __asm__ __volatile__ + ("movb %%al,%%ah\n" + "1:\n\t" + "movb (%0),%%al\n\t" + "cmpb %%ah,%%al\n\t" + "je 2f\n\t" + "leal 1(%0),%0\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n\t" + "xorl %0,%0\n" + "2:" + : "=r" (__res) + : "a" (__c), "0" (__s) + : "ax", "cc"); + return __res; +} + +__STRING_INLINE char * +__strchr_c (__const char *__s, int __c) +{ + register char *__res; + __asm__ __volatile__ + ("1:\n\t" + "movb (%0),%%al\n\t" + "cmpb %%ah,%%al\n\t" + "je 2f\n\t" + "leal 1(%0),%0\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n\t" + "xorl %0,%0\n" + "2:" + : "=r" (__res) + : "a" (__c), "0" (__s) + : "ax", "cc"); + return __res; +} + + +/* Find the last occurrence of C in S. */ +#define strrchr(s, c) \ + (__extension__ (__builtin_constant_p (c) \ + ? __strrchr_c (s, ((c) & 0xff) << 8) \ + : __strrchr_g (s, c))) + +__STRING_INLINE char * +__strrchr_g (__const char *__s, int __c) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" + "movb %%al,%%ah\n" + "1:\n\t" + "lodsb\n\t" + "cmpb %%ah,%%al\n\t" + "jne 2f\n\t" + "leal -1(%%esi),%0\n" + "2:\n\t" + "testb %%al,%%al\n\t" + "jne 1b" + : "=d" (__res) + : "0" (0), "S" (__s),"a" (__c) + : "ax", "si", "cc"); + return __res; +} + +__STRING_INLINE char * +__strrchr_c (__const char *__s, int __c) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" + "1:\n\t" + "lodsb\n\t" + "cmpb %%ah,%%al\n\t" + "jne 2f\n\t" + "leal -1(%%esi),%0\n" + "2:\n\t" + "testb %%al,%%al\n\t" + "jne 1b" + : "=d" (__res) + : "0" (0), "S" (__s),"a" (__c) + : "ax", "si", "cc"); + return __res; +} + + +/* Return the length of the initial segment of S which + consists entirely of characters not in REJECT. */ +#ifdef __PIC__ +__STRING_INLINE size_t +strcspn (__const char *__s, __const char *__reject) +{ + register char *__res; + __asm__ __volatile__ + ("push %%ebx\n\t" + "cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%ebx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%ebx,%%ecx\n\t" + "repne; scasb\n\t" + "jne 1b\n" + "2:\n\t" + "popl %%ebx" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__reject) + : "ax", "cx", "di", "cc"); + return (__res - 1) - __s; +} +#else +__STRING_INLINE size_t +strcspn (__const char *__s, __const char *__reject) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%edx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%edx,%%ecx\n\t" + "repne; scasb\n\t" + "jne 1b\n" + "2:" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__reject) + : "ax", "cx", "dx", "di", "cc"); + return (__res - 1) - __s; +} +#endif + + +/* Return the length of the initial segment of S which + consists entirely of characters in ACCEPT. */ +#ifdef __PIC__ +__STRING_INLINE size_t +strspn (__const char *__s, __const char *__accept) +{ + register char *__res; + __asm__ __volatile__ + ("pushl %%ebx\n\t" + "cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%ebx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%ebx,%%ecx\n\t" + "repne; scasb\n\t" + "je 1b\n" + "2:\n\t" + "popl %%ebx" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__accept) + : "ax", "cx", "di", "cc"); + return (__res - 1) - __s; +} +#else +__STRING_INLINE size_t +strspn (__const char *__s, __const char *__accept) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%edx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%edx,%%ecx\n\t" + "repne; scasb\n\t" + "je 1b\n" + "2:" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__accept) + : "ax", "cx", "dx", "di", "cc"); + return (__res - 1) - __s; +} +#endif + + +/* Find the first occurrence in S of any character in ACCEPT. */ +#ifdef __PIC__ +__STRING_INLINE char * +strpbrk (__const char *__s, __const char *__accept) +{ + register char *__res; + __asm__ __volatile__ + ("pushl %%ebx\n\t" + "cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%ebx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%ebx,%%ecx\n\t" + "repne; scasb\n\t" + "jne 1b\n\t" + "decl %0\n\t" + "jmp 3f\n" + "2:\n\t" + "xorl %0,%0\n" + "3:\n\t" + "popl %%ebx" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__accept) + : "ax", "cx", "di", "cc"); + return __res; +} +#else +__STRING_INLINE char * +strpbrk (__const char *__s, __const char *__accept) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" + "movl %%ecx,%%edx\n" + "1:\n\t" + "lodsb\n\t" + "testb %%al,%%al\n\t" + "je 2f\n\t" + "movl %4,%%edi\n\t" + "movl %%edx,%%ecx\n\t" + "repne; scasb\n\t" + "jne 1b\n\t" + "decl %0\n\t" + "jmp 3f\n" + "2:\n\t" + "xorl %0,%0\n" + "3:" + : "=S" (__res) + : "a" (0), "c" (0xffffffff), "0" (__s), "g" (__accept) + : "ax", "cx", "dx", "di", "cc"); + return __res; +} +#endif + + +/* Find the first occurrence of NEEDLE in HAYSTACK. */ +#ifdef __PIC__ +__STRING_INLINE char * +strstr (__const char *__haystack, __const char *__needle) +{ + register char *__res; + __asm__ __volatile__ + ("pushl %%ebx\n\t" + "cld\n\t" \ + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" /* NOTE! This also sets Z if searchstring='' */ + "movl %%ecx,%%ebx\n" + "1:\n\t" + "movl %4,%%edi\n\t" + "movl %%esi,%%eax\n\t" + "movl %%ebx,%%ecx\n\t" + "repe; cmpsb\n\t" + "je 2f\n\t" /* also works for empty string, see above */ + "xchgl %%eax,%%esi\n\t" + "incl %%esi\n\t" + "cmpb $0,-1(%%eax)\n\t" + "jne 1b\n\t" + "xorl %%eax,%%eax\n\t" + "2:\n\t" + "popl %%ebx" + : "=a" (__res) + : "0" (0), "c" (0xffffffff), "S" (__haystack), "g" (__needle) + : "cx", "di", "si", "cc"); + return __res; +} +#else +__STRING_INLINE char * +strstr (__const char *__haystack, __const char *__needle) +{ + register char *__res; + __asm__ __volatile__ + ("cld\n\t" \ + "movl %4,%%edi\n\t" + "repne; scasb\n\t" + "notl %%ecx\n\t" + "decl %%ecx\n\t" /* NOTE! This also sets Z if searchstring='' */ + "movl %%ecx,%%edx\n" + "1:\n\t" + "movl %4,%%edi\n\t" + "movl %%esi,%%eax\n\t" + "movl %%edx,%%ecx\n\t" + "repe; cmpsb\n\t" + "je 2f\n\t" /* also works for empty string, see above */ + "xchgl %%eax,%%esi\n\t" + "incl %%esi\n\t" + "cmpb $0,-1(%%eax)\n\t" + "jne 1b\n\t" + "xorl %%eax,%%eax\n\t" + "2:" + : "=a" (__res) + : "0" (0), "c" (0xffffffff), "S" (__haystack), "g" (__needle) + : "cx", "dx", "di", "si", "cc"); + return __res; +} +#endif + + +#undef __STRING_INLINE + +#endif /* GNU CC */ |