| /* |
| * 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> |
| |
| #undef memcpy |
| void *memcpy(void * to, const void * from, size_t n) |
| { |
| int d0, d1, d2; |
| __asm__ __volatile__( |
| " rep; movsl\n" |
| " movl %4, %%ecx\n" |
| " andl $3, %%ecx\n" |
| /* jz is optional. avoids "rep; movsb" with ecx == 0, |
| * but adds a branch, which is currently (2008) faster */ |
| " jz 1f\n" |
| " rep; movsb\n" |
| "1:\n" |
| : "=&c" (d0), "=&D" (d1), "=&S" (d2) |
| : "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from) |
| : "memory" |
| ); |
| return to; |
| } |
| libc_hidden_def(memcpy) |