1 | /* Highly optimized version for ix86, x>=6. |
2 | Copyright (C) 1999-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <sysdep.h> |
20 | #include "asm-syntax.h" |
21 | |
22 | #define PARMS 4 /* no space for saved regs */ |
23 | #define STR1 PARMS |
24 | #define STR2 STR1+4 |
25 | |
26 | .text |
27 | ENTRY (strcmp) |
28 | |
29 | movl STR1(%esp), %ecx |
30 | movl STR2(%esp), %edx |
31 | |
32 | L(oop): movb (%ecx), %al |
33 | cmpb (%edx), %al |
34 | jne L(neq) |
35 | incl %ecx |
36 | incl %edx |
37 | testb %al, %al |
38 | jnz L(oop) |
39 | |
40 | xorl %eax, %eax |
41 | /* when strings are equal, pointers rest one beyond |
42 | the end of the NUL terminators. */ |
43 | ret |
44 | |
45 | L(neq): movl $1, %eax |
46 | movl $-1, %ecx |
47 | cmovbl %ecx, %eax |
48 | |
49 | ret |
50 | END (strcmp) |
51 | libc_hidden_builtin_def (strcmp) |
52 | |