b6cbf7203b
This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
124 lines
3.8 KiB
ArmAsm
124 lines
3.8 KiB
ArmAsm
/* $NetBSD: bcmp.S,v 1.9 2009/12/14 01:07:42 matt Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1991, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Ralph Campbell.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <mips/asm.h>
|
|
#define _LOCORE /* XXX not really, just assembly-code source */
|
|
#include <machine/endian.h> /* LWLO/LWHI, SWLO/SWHI */
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
#if 0
|
|
RCSID("from: @(#)bcmp.s 8.1 (Berkeley) 6/4/93")
|
|
#else
|
|
RCSID("$NetBSD: bcmp.S,v 1.9 2009/12/14 01:07:42 matt Exp $")
|
|
#endif
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
/* bcmp(s1, s2, n) */
|
|
|
|
|
|
LEAF(bcmp)
|
|
.set noreorder
|
|
blt a2, 16, small # is it worth any trouble?
|
|
xor v0, a0, a1 # compare low two bits of addresses
|
|
and v0, v0, 3
|
|
PTR_SUBU a3, zero, a1 # compute # bytes to word align address
|
|
bne v0, zero, unaligned # not possible to align addresses
|
|
and a3, a3, 3
|
|
|
|
beq a3, zero, 1f
|
|
PTR_SUBU a2, a2, a3 # subtract from remaining count
|
|
move v0, v1 # init v0,v1 so unmodified bytes match
|
|
LWHI v0, 0(a0) # read 1, 2, or 3 bytes
|
|
LWHI v1, 0(a1)
|
|
PTR_ADDU a1, a1, a3
|
|
bne v0, v1, nomatch
|
|
PTR_ADDU a0, a0, a3
|
|
1:
|
|
and a3, a2, ~3 # compute number of whole words left
|
|
PTR_SUBU a2, a2, a3 # which has to be >= (16-3) & ~3
|
|
PTR_ADDU a3, a3, a0 # compute ending address
|
|
2:
|
|
lw v0, 0(a0) # compare words
|
|
lw v1, 0(a1)
|
|
PTR_ADDU a0, a0, 4
|
|
bne v0, v1, nomatch
|
|
PTR_ADDU a1, a1, 4
|
|
bne a0, a3, 2b
|
|
nop
|
|
b small # finish remainder
|
|
nop
|
|
unaligned:
|
|
beq a3, zero, 2f
|
|
PTR_SUBU a2, a2, a3 # subtract from remaining count
|
|
PTR_ADDU a3, a3, a0 # compute ending address
|
|
1:
|
|
lbu v0, 0(a0) # compare bytes until a1 word aligned
|
|
lbu v1, 0(a1)
|
|
PTR_ADDU a0, a0, 1
|
|
bne v0, v1, nomatch
|
|
PTR_ADDU a1, a1, 1
|
|
bne a0, a3, 1b
|
|
nop
|
|
2:
|
|
and a3, a2, ~3 # compute number of whole words left
|
|
PTR_SUBU a2, a2, a3 # which has to be >= (16-3) & ~3
|
|
PTR_ADDU a3, a3, a0 # compute ending address
|
|
3:
|
|
LWHI v0, 0(a0) # compare words a0 unaligned, a1 aligned
|
|
LWLO v0, 3(a0)
|
|
lw v1, 0(a1)
|
|
PTR_ADDU a0, a0, 4
|
|
bne v0, v1, nomatch
|
|
PTR_ADDU a1, a1, 4
|
|
bne a0, a3, 3b
|
|
nop
|
|
small:
|
|
ble a2, zero, match
|
|
PTR_ADDU a3, a2, a0 # compute ending address
|
|
1:
|
|
lbu v0, 0(a0)
|
|
lbu v1, 0(a1)
|
|
PTR_ADDU a0, a0, 1
|
|
bne v0, v1, nomatch
|
|
PTR_ADDU a1, a1, 1
|
|
bne a0, a3, 1b
|
|
nop
|
|
match:
|
|
j ra
|
|
move v0, zero
|
|
nomatch:
|
|
j ra
|
|
li v0, 1
|
|
.set reorder
|
|
END(bcmp)
|