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/*
* Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stddef.h>
#include <string.h>
#include <stdint.h>
void *memset(void *dst, int val, size_t count)
{
uint8_t *ptr = dst;
uint64_t *ptr64;
uint64_t fill = (unsigned char)val;
/* Simplify code below by making sure we write at least one byte. */
if (count == 0U) {
return dst;
}
/* Handle the first part, until the pointer becomes 64-bit aligned. */
while (((uintptr_t)ptr & 7U) != 0U) {
*ptr = (uint8_t)val;
ptr++;
if (--count == 0U) {
return dst;
}
}
/* Duplicate the fill byte to the rest of the 64-bit word. */
fill |= fill << 8;
fill |= fill << 16;
fill |= fill << 32;
/* Use 64-bit writes for as long as possible. */
ptr64 = (uint64_t *)ptr;
for (; count >= 8U; count -= 8) {
*ptr64 = fill;
ptr64++;
}
/* Handle the remaining part byte-per-byte. */
ptr = (uint8_t *)ptr64;
while (count-- > 0U) {
*ptr = (uint8_t)val;
ptr++;
}
return dst;
}
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