glibc/sysdeps/sparc/sparc32/memchr.S

143 lines
3.1 KiB
ArmAsm

/* memchr (str, ch, n) -- Return pointer to first occurrence of CH in STR less
than N.
For SPARC v7.
Copyright (C) 1996-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jj@ultra.linux.cz> and
David S. Miller <davem@caip.rutgers.edu>.
This version is developed using the same algorithm as the fast C
version which carries the following introduction:
Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
with help from Dan Sahlin (dan@sics.se) and
commentary by Jim Blandy (jimb@ai.mit.edu);
adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu),
and implemented by Roland McGrath (roland@ai.mit.edu).
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/>. */
#include <sysdep.h>
.text
.align 4
ENTRY(__memchr)
andcc %o1, 0xff, %o1
sll %o1, 8, %g6
andcc %o0, 3, %g0
or %o1, %g6, %g6
sll %g6, 16, %o3
be 10f
or %o3, %g6, %g2
cmp %o2, 0
be 9f
sethi %hi(0x80808080), %o4
ldub [%o0], %g4
cmp %g4, %o1
be 1f
add %o0, 1, %o0
subcc %o2, 1, %o2
be 9f
andcc %o0, 3, %g0
be 4f
or %o4, %lo(0x80808080), %o3
ldub [%o0], %g4
cmp %g4, %o1
be 1f
add %o0, 1, %o0
subcc %o2, 1, %o2
be 9f
andcc %o0, 3, %g0
be 5f
sethi %hi(0x01010101), %o5
ldub [%o0], %g4
cmp %g4, %o1
be 1f
add %o0, 1, %o0
subcc %o2, 1, %o2
bne,a 7f
and %o2, 3, %g1
retl
clr %o0
1: retl
sub %o0, 1, %o0
10: sethi %hi(0x80808080), %o4
or %o4, %lo(0x80808080), %o3
4: sethi %hi(0x01010101), %o5
5: and %o2, 3, %g1
7: andcc %o2, 0xfffffffc, %o2
be 0f
or %o5, %lo(0x01010101), %g6
ld [%o0], %g4
6: xor %g4, %g2, %g5
add %o0, 4, %o0
sub %g5, %g6, %g5
andcc %g5, %o3, %g0
bne 8f
subcc %o2, 4, %o2
bne,a 6b
ld [%o0], %g4
0: cmp %g1, 0
1: be 9f
add %o0, 4, %o0
ldub [%o0 - 4], %g4
cmp %g4, %o1
be 4f
cmp %g1, 1
be 9f
ldub [%o0 - 3], %g4
cmp %g4, %o1
be 3f
cmp %g1, 2
be 9f
ldub [%o0 - 2], %g4
cmp %g4, %o1
be 2f
nop
9: retl
clr %o0
/* Check every byte. */
8: srl %g4, 24, %g5
and %g5, 0xff, %g5
cmp %g5, %o1
be 4f
srl %g4, 16, %g5
and %g5, 0xff, %g5
cmp %g5, %o1
be 3f
srl %g4, 8, %g5
and %g5, 0xff, %g5
cmp %g5, %o1
be 2f
and %g4, 0xff, %g5
cmp %g5, %o1
be 1f
cmp %o2, 0
bne,a 6b
ld [%o0], %g4
b 1b
cmp %g1, 0
1: retl
sub %o0, 1, %o0
2: retl
sub %o0, 2, %o0
3: retl
sub %o0, 3, %o0
4: retl
sub %o0, 4, %o0
END(__memchr)
weak_alias (__memchr, memchr)
libc_hidden_builtin_def (memchr)