historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/roms/skiboot/libc/string/memset.c
2024-01-16 11:20:27 -06:00

54 lines
1.3 KiB
C

/******************************************************************************
* Copyright (c) 2004, 2008 IBM Corporation
* All rights reserved.
* This program and the accompanying materials
* are made available under the terms of the BSD License
* which accompanies this distribution, and is available at
* http://www.opensource.org/licenses/bsd-license.php
*
* Contributors:
* IBM Corporation - initial implementation
*****************************************************************************/
#define CACHE_LINE_SIZE 128
#include <stddef.h>
void *memset(void *dest, int c, size_t size);
void *memset(void *dest, int c, size_t size)
{
unsigned char *d = (unsigned char *)dest;
unsigned long big_c = 0;
#if defined(__powerpc__) || defined(__powerpc64__)
if (size > CACHE_LINE_SIZE && c==0) {
while ((unsigned long long)d % CACHE_LINE_SIZE) {
*d++ = (unsigned char)c;
size--;
}
while (size >= CACHE_LINE_SIZE) {
asm volatile ("dcbz 0,%0\n" : : "r"(d) : "memory");
d+= CACHE_LINE_SIZE;
size-= CACHE_LINE_SIZE;
}
}
#endif
if (c) {
big_c = c;
big_c |= (big_c << 8) | big_c;
big_c |= (big_c << 16) | big_c;
big_c |= (big_c << 32) | big_c;
}
while (size >= 8 && c == 0) {
*((unsigned long *)d) = big_c;
d+=8;
size-=8;
}
while (size-- > 0) {
*d++ = (unsigned char)c;
}
return dest;
}