rockbox/firmware/common/memset16.c
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

77 lines
2.2 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Jens Arnold
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <string.h>
#define LBLOCKSIZE (sizeof(long)/2)
#define UNALIGNED(X) ((long)X & (sizeof(long) - 1))
#define TOO_SMALL(LEN) ((LEN) < LBLOCKSIZE)
void memset16(void *dst, int val, size_t len)
{
#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
unsigned short *p = (unsigned short *)dst;
while (len--)
*p++ = val;
#else
unsigned short *p = (unsigned short *)dst;
unsigned int i;
unsigned long buffer;
unsigned long *aligned_addr;
if (!TOO_SMALL(len) && !UNALIGNED(dst))
{
aligned_addr = (unsigned long *)dst;
val &= 0xffff;
if (LBLOCKSIZE == 2)
{
buffer = (val << 16) | val;
}
else
{
buffer = 0;
for (i = 0; i < LBLOCKSIZE; i++)
buffer = (buffer << 16) | val;
}
while (len >= LBLOCKSIZE*4)
{
*aligned_addr++ = buffer;
*aligned_addr++ = buffer;
*aligned_addr++ = buffer;
*aligned_addr++ = buffer;
len -= 4*LBLOCKSIZE;
}
while (len >= LBLOCKSIZE)
{
*aligned_addr++ = buffer;
len -= LBLOCKSIZE;
}
p = (unsigned short *)aligned_addr;
}
while (len--)
*p++ = val;
#endif /* not PREFER_SIZE_OVER_SPEED */
}