mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-27 05:00:15 +00:00
62 lines
1.7 KiB
ArmAsm
62 lines
1.7 KiB
ArmAsm
/* 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)
|