1 | /* Optimized version of the standard strcmp() function. |
2 | This file is part of the GNU C Library. |
3 | Copyright (C) 2000-2022 Free Software Foundation, Inc. |
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 | /* Return: the result of the comparison |
20 | |
21 | Inputs: |
22 | in0: s1 |
23 | in1: s2 |
24 | |
25 | Unlike memcmp(), this function is optimized for mismatches within the |
26 | first few characters. */ |
27 | |
28 | #include <sysdep.h> |
29 | #undef ret |
30 | |
31 | #define s1 in0 |
32 | #define s2 in1 |
33 | |
34 | #define val1 r15 |
35 | #define val2 r16 |
36 | |
37 | |
38 | ENTRY(strcmp) |
39 | alloc r2 = ar.pfs, 2, 0, 0, 0 |
40 | .loop: |
41 | ld1 val1 = [s1], 1 |
42 | ld1 val2 = [s2], 1 |
43 | cmp.eq p6, p0 = r0, r0 // set p6 |
44 | ;; |
45 | cmp.ne.and p6, p0 = val1, r0 |
46 | cmp.ne.and p6, p0 = val2, r0 |
47 | cmp.eq.and p6, p0 = val1, val2 |
48 | (p6) br.cond.sptk .loop |
49 | sub ret0 = val1, val2 |
50 | br.ret.sptk.many b0 |
51 | END(strcmp) |
52 | libc_hidden_builtin_def (strcmp) |
53 | |