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/*
* 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 strtok,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.
*/
/*
* Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
*
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
/*
* Modified for uClibc by Erik Andersen <andersen@codepoet.org>
* These make no attempt to use nifty things like mmx/3dnow/etc.
* These are not inline, and will therefore not be as fast as
* modifying the headers to use inlines (and cannot therefore
* do tricky things when dealing with const memory). But they
* should (I hope!) be faster than their generic equivalents....
*
* More importantly, these should provide a good example for
* others to follow when adding arch specific optimizations.
* -Erik
*/
#include <string.h>
/* Experimentally off - libc_hidden_proto(strrchr) */
char *strrchr(const char *s, int c)
{
char *retval;
__asm__ __volatile__(
" movb %%cl, %%ch\n"
"1: movb (%1), %%cl\n" /* load char */
" cmpb %%cl, %%ch\n" /* char == c? */
" jne 2f\n"
" movl %1, %0\n"
"2: incl %1\n"
" testb %%cl, %%cl\n" /* char == NUL? */
" jnz 1b\n"
/* "=c": use ecx, not ebx (-fpic uses it). */
: "=a" (retval), "=r" (s), "=c" (c)
: "0" (0), "1" (s), "2" (c)
/* : no clobbers */
);
return retval;
}
libc_hidden_def(strrchr)
#ifdef __UCLIBC_SUSV3_LEGACY__
strong_alias(strrchr,rindex)
#endif
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