| /* |
| * 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 memmove |
| /*#define memmove TESTING*/ |
| void *memmove(void *dest, const void *src, size_t n) |
| { |
| int eax, ecx, esi, edi; |
| __asm__ __volatile__( |
| " movl %%eax, %%edi\n" |
| " cmpl %%esi, %%eax\n" |
| " je 2f\n" /* (optional) src == dest -> NOP */ |
| " jb 1f\n" /* src > dest -> simple copy */ |
| " leal -1(%%esi,%%ecx), %%esi\n" |
| " leal -1(%%eax,%%ecx), %%edi\n" |
| " std\n" |
| "1: rep; movsb\n" |
| " cld\n" |
| "2:\n" |
| : "=&c" (ecx), "=&S" (esi), "=&a" (eax), "=&D" (edi) |
| : "0" (n), "1" (src), "2" (dest) |
| : "memory" |
| ); |
| return (void*)eax; |
| } |
| #ifndef memmove |
| libc_hidden_def(memmove) |
| #else |
| /* Uncomment TESTING, gcc -D_GNU_SOURCE -m32 -Os memmove.c -o memmove |
| * and run ./memmove |
| */ |
| int main() |
| { |
| static char str[] = "abcdef.123"; |
| memmove(str + 1, str, 5); |
| printf(strcmp(str, "aabcde.123") == 0 ? "ok\n" : "BAD!\n"); |
| memmove(str, str + 1, 5); |
| printf(strcmp(str, "abcdee.123") == 0 ? "ok\n" : "BAD!\n"); |
| } |
| #endif |