| /* Optimized version of the standard strncmp() function. |
| This file is part of the GNU C Library. |
| Copyright (C) 2000-2016 Free Software Foundation, Inc. |
| Contributed by Dan Pop <Dan.Pop@cern.ch>. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* Return: the result of the comparison |
| |
| Inputs: |
| in0: s1 |
| in1: s2 |
| in2: n |
| |
| Unlike memcmp(), this function is optimized for mismatches within the |
| first few characters. */ |
| |
| #include <sysdep.h> |
| #undef ret |
| |
| #define s1 in0 |
| #define s2 in1 |
| #define n in2 |
| |
| #define val1 r15 |
| #define val2 r16 |
| |
| |
| ENTRY(strncmp) |
| alloc r2 = ar.pfs, 3, 0, 0, 0 |
| mov ret0 = r0 |
| cmp.eq p6, p0 = r0, r0 // set p6 |
| cmp.eq p7, p0 = n, r0 // return immediately if n == 0 |
| (p7) br.cond.spnt .restore_and_exit ;; |
| .loop: |
| ld1 val1 = [s1], 1 |
| ld1 val2 = [s2], 1 |
| adds n = -1, n // n-- |
| ;; |
| cmp.ne.and p6, p0 = val1, r0 |
| cmp.ne.and p6, p0 = val2, r0 |
| cmp.ne.and p6, p0 = n, r0 |
| cmp.eq.and p6, p0 = val1, val2 |
| (p6) br.cond.sptk .loop |
| sub ret0 = val1, val2 |
| .restore_and_exit: |
| br.ret.sptk.many b0 |
| END(strncmp) |
| libc_hidden_builtin_def (strncmp) |