e1dd10ddfb
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12843 a1c6a512-1295-4272-9138-f99709370657
44 lines
2.1 KiB
ArmAsm
44 lines
2.1 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:
|
|
@ r0 = buf1
|
|
@ r1 = buf2
|
|
@ r2 = len
|
|
movs r2, r2, lsr #4 @ bytes => lines, len == 0?
|
|
moveq pc, lr @ not at least a line? leave
|
|
stmdb sp!, { r4-r10, lr } @ save registers and return address
|
|
.loop: @
|
|
ldmia r0, { r3-r6 } @ read four longwords from buf1
|
|
ldmia r1, { r7-r10 } @ read four longwords from buf2
|
|
stmia r0!, { r7-r10 } @ write buf2 data to buf1, buf1 += 16
|
|
stmia r1!, { r3-r6 } @ write buf1 data to buf2, buf2 += 16
|
|
subs r2, r2, #1 @ len -= 1, len > 0 ?
|
|
bhi .loop @ yes? keep exchanging
|
|
ldmia sp!, { r4-r10, pc } @ restore registers and return
|
|
.end:
|
|
.size memswap128, .end-memswap128
|
|
|