glibc/sysdeps/sparc/sparc32/memchr.S
2012-02-09 23:18:22 +00:00

146 lines
3.2 KiB
ArmAsm

/* memchr (str, ch, n) -- Return pointer to first occurrence of CH in STR less
than N.
For SPARC v7.
Copyright (C) 1996, 1999, 2000, 2003 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)
#if !__BOUNDED_POINTERS__
weak_alias (__memchr, __ubp_memchr)
#endif
libc_hidden_builtin_def (memchr)