acrn-kernel/arch/v850/lib/memset.c

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/*
* arch/v850/lib/memset.c -- Memory initialization
*
* Copyright (C) 2001,02,04 NEC Corporation
* Copyright (C) 2001,02,04 Miles Bader <miles@gnu.org>
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*
* Written by Miles Bader <miles@gnu.org>
*/
#include <linux/types.h>
void *memset (void *dst, int val, __kernel_size_t count)
{
if (count) {
register unsigned loop;
register void *ptr asm ("ep") = dst;
/* replicate VAL into a long. */
val &= 0xff;
val |= val << 8;
val |= val << 16;
/* copy initial unaligned bytes. */
if ((long)ptr & 1) {
*(char *)ptr = val;
ptr = (void *)((char *)ptr + 1);
count--;
}
if (count > 2 && ((long)ptr & 2)) {
*(short *)ptr = val;
ptr = (void *)((short *)ptr + 1);
count -= 2;
}
/* 32-byte copying loop. */
for (loop = count / 32; loop; loop--) {
asm ("sst.w %0, 0[ep]; sst.w %0, 4[ep];"
"sst.w %0, 8[ep]; sst.w %0, 12[ep];"
"sst.w %0, 16[ep]; sst.w %0, 20[ep];"
"sst.w %0, 24[ep]; sst.w %0, 28[ep]"
:: "r" (val) : "memory");
ptr += 32;
}
count %= 32;
/* long copying loop. */
for (loop = count / 4; loop; loop--) {
*(long *)ptr = val;
ptr = (void *)((long *)ptr + 1);
}
count %= 4;
/* finish up with any trailing bytes. */
if (count & 2) {
*(short *)ptr = val;
ptr = (void *)((short *)ptr + 1);
}
if (count & 1) {
*(char *)ptr = val;
}
}
return dst;
}