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/* $OpenBSD: bzero.S,v 1.2 1996/09/27 06:47:45 mickey Exp $ */
/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
*/
#include <machine/asm.h>
ENTRY(bzero)
pushl %edi
movl 8(%esp),%edi
movl 12(%esp),%edx
cld /* set fill direction forward */
xorl %eax,%eax /* set fill data to 0 */
/*
* if the string is too short, it's really not worth the overhead
* of aligning to word boundries, etc. So we jump to a plain
* unaligned set.
*/
cmpl $16,%edx
jb L1
movl %edi,%ecx /* compute misalignment */
negl %ecx
andl $3,%ecx
subl %ecx,%edx
rep /* zero until word aligned */
stosb
movl %edx,%ecx /* zero by words */
shrl $2,%ecx
andl $3,%edx
rep
stosl
L1: movl %edx,%ecx /* zero remainder by bytes */
rep
stosb
popl %edi
ret
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