rockbox/firmware/target/coldfire/memswap128-coldfire.S
Michael Sevakis 600ca577dc Rrrr. Editor shouldn't have left those tabs. Will check settings.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12845 a1c6a512-1295-4272-9138-f99709370657
2007-03-19 22:14:10 +00:00

50 lines
2.4 KiB
ArmAsm

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Michael Sevakis
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/****************************************************************************
* void memswap128(void *buf1, void *buf2, size_t len)
*/
.section .icode, "ax", @progbits
.align 2
.global memswap128
.type memswap128, @function
memswap128:
lea.l -28(%sp), %sp | save registers
movem.l %d2-%d7/%a2, (%sp) |
movem.l 32(%sp), %a0-%a2 | %a0 = buf1
| %a1 = buf2
| %a2 = len
lea.l -15(%a0, %a2.l), %a2 | %a2 = end address - 15
cmp.l %a0, %a2 | end address <= buf1?
bls.b .no_lines | not at least a line? leave
.loop: |
movem.l (%a0), %d0-%d3 | read four longwords from buf1
movem.l (%a1), %d4-%d7 | read four longwords from buf2
movem.l %d4-%d7, (%a0) | write buf2 data to buf1
movem.l %d0-%d3, (%a1) | write buf1 data to buf2
lea.l 16(%a0), %a0 | buf1 += 16
lea.l 16(%a1), %a1 | buf2 += 16
cmp.l %a0, %a2 | %a0 < %d0?
bhi.b .loop | yes? keep exchanging
.no_lines: |
movem.l (%sp), %d2-%d7/%a2 | restore registers
lea.l 28(%sp), %sp |
rts |
.end:
.size memswap128, .end-memswap128