81 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
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|  * Copyright (C) 2004 Microtronix Datacom Ltd
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|  *
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  */
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| 
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| #include <linux/types.h>
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| #include <linux/string.h>
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| 
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| void *memmove(void *d, const void *s, size_t count)
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| {
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| 	unsigned long dst, src;
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| 
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| 	if (!count)
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| 		return d;
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| 
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| 	if (d < s) {
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| 		dst = (unsigned long) d;
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| 		src = (unsigned long) s;
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| 
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| 		if ((count < 8) || ((dst ^ src) & 3))
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| 			goto restup;
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| 
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| 		if (dst & 1) {
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| 			*(char *)dst++ = *(char *)src++;
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| 			count--;
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| 		}
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| 		if (dst & 2) {
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| 			*(short *)dst = *(short *)src;
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| 			src += 2;
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| 			dst += 2;
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| 			count -= 2;
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| 		}
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| 		while (count > 3) {
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| 			*(long *)dst = *(long *)src;
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| 			src += 4;
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| 			dst += 4;
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| 			count -= 4;
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| 		}
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| restup:
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| 		while (count--)
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| 			*(char *)dst++ = *(char *)src++;
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| 	} else {
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| 		dst = (unsigned long) d + count;
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| 		src = (unsigned long) s + count;
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| 
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| 		if ((count < 8) || ((dst ^ src) & 3))
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| 			goto restdown;
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| 
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| 		if (dst & 1) {
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| 			src--;
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| 			dst--;
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| 			count--;
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| 			*(char *)dst = *(char *)src;
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| 		}
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| 		if (dst & 2) {
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| 			src -= 2;
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| 			dst -= 2;
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| 			count -= 2;
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| 			*(short *)dst = *(short *)src;
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| 		}
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| 		while (count > 3) {
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| 			src -= 4;
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| 			dst -= 4;
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| 			count -= 4;
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| 			*(long *)dst = *(long *)src;
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| 		}
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| restdown:
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| 		while (count--) {
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| 			src--;
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| 			dst--;
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| 			*(char *)dst = *(char *)src;
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| 		}
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| 	}
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| 
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| 	return d;
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| }
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