More small optimizations for x86-64 strlen.
[glibc.git] / string / strcpy.c
blobc736a60762b72e605afdc3bb9f18d0de7cb4e4fb
1 /* Copyright (C) 1991, 1997, 2000, 2003 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
19 #include <stddef.h>
20 #include <string.h>
21 #include <memcopy.h>
22 #include <bp-checks.h>
24 #undef strcpy
26 /* Copy SRC to DEST. */
27 char *
28 strcpy (dest, src)
29 char *dest;
30 const char *src;
32 reg_char c;
33 char *__unbounded s = (char *__unbounded) CHECK_BOUNDS_LOW (src);
34 const ptrdiff_t off = CHECK_BOUNDS_LOW (dest) - s - 1;
35 size_t n;
39 c = *s++;
40 s[off] = c;
42 while (c != '\0');
44 n = s - src;
45 (void) CHECK_BOUNDS_HIGH (src + n);
46 (void) CHECK_BOUNDS_HIGH (dest + n);
48 return dest;
50 libc_hidden_builtin_def (strcpy)