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/*
* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2007 John Williams
*
* Reasonably optimised generic C-code for memset on Microblaze
* This is generic C code to do efficient, alignment-aware memcpy.
*
* It is based on demo code originally Copyright 2001 by Intel Corp, taken from
* http://www.embedded.com/showArticle.jhtml?articleID=19205567
*
* Attempts were made, unsuccessfully, to contact the original
* author of this code (Michael Morrow, Intel). Below is the original
* copyright notice.
*
* This software has been developed by Intel Corporation.
* Intel specifically disclaims all warranties, express or
* implied, and all liability, including consequential and
* other indirect damages, for the use of this program, including
* liability for infringement of any proprietary rights,
* and including the warranties of merchantability and fitness
* for a particular purpose. Intel does not assume any
* responsibility for and errors which may appear in this program
* not any responsibility to update it.
*/
#include <linux/export.h>
#include <linux/types.h>
#include <linux/stddef.h>
#include <linux/compiler.h>
#include <linux/string.h>
#ifdef CONFIG_OPT_LIB_FUNCTION
void *memset(void *v_src, int c, __kernel_size_t n)
{
char *src = v_src;
uint32_t *i_src;
uint32_t w32 = 0;
/* Truncate c to 8 bits */
c = (c & 0xFF);
if (unlikely(c)) {
/* Make a repeating word out of it */
w32 = c;
w32 |= w32 << 8;
w32 |= w32 << 16;
}
if (likely(n >= 4)) {
/* Align the destination to a word boundary */
/* This is done in an endian independent manner */
switch ((unsigned) src & 3) {
case 1:
*src++ = c;
--n;
fallthrough;
case 2:
*src++ = c;
--n;
fallthrough;
case 3:
*src++ = c;
--n;
}
i_src = (void *)src;
/* Do as many full-word copies as we can */
for (; n >= 4; n -= 4)
*i_src++ = w32;
src = (void *)i_src;
}
/* Simple, byte oriented memset or the rest of count. */
switch (n) {
case 3:
*src++ = c;
fallthrough;
case 2:
*src++ = c;
fallthrough;
case 1:
*src++ = c;
break;
default:
break;
}
return v_src;
}
EXPORT_SYMBOL(memset);
#endif /* CONFIG_OPT_LIB_FUNCTION */
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