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/*! \file memset.c
\brief memset function
\author Markus L. Noga <markus@noga.de>
*/
/*
* The contents of this file are subject to the Mozilla Public License
* Version 1.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* The Original Code is legOS code, released October 17, 1999.
*
* The Initial Developer of the Original Code is Markus L. Noga.
* Portions created by Markus L. Noga are Copyright (C) 1999
* Markus L. Noga. All Rights Reserved.
*
* Contributor(s): Markus L. Noga <markus@noga.de>
*/
typedef unsigned size_t; // data type for memory sizes
///////////////////////////////////////////////////////////////////////////////
//
// Functions
//
///////////////////////////////////////////////////////////////////////////////
//! fill memory block with a byte value.
/*! \param s start
\param c byte fill value
\param n number of bytes to fill
*/
void *memset(void* s,int c,size_t n) {
void *res;
__asm__ __volatile__(
" add.w %1,%0\n"
"0:cmp.w %1,%0\n"
" beq 1f\n"
" mov.b %2l,@-%0\n"
" bra 0b\n"
"1:"
: "=&r" (res) // output
: "r" (s), "r" (c), "0" (n) // input
: "cc","memory" // clobbered (final)
);
return res;
}
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