| Current Path : /usr/src/lib/libc/amd64/string/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libc/amd64/string/bzero.S |
/*
* Written by J.T. Conklin <jtc@NetBSD.org>.
* Public domain.
* Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD: release/9.1.0/lib/libc/amd64/string/bzero.S 217106 2011-01-07 16:08:40Z kib $");
#if 0
RCSID("$NetBSD: bzero.S,v 1.2 2003/07/26 19:24:38 salo Exp $")
#endif
ENTRY(bzero)
cld /* set fill direction forward */
xorq %rax,%rax /* 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.
*/
cmpq $16,%rsi
jb L1
movq %rdi,%rcx /* compute misalignment */
negq %rcx
andq $7,%rcx
subq %rcx,%rsi
rep /* zero until word aligned */
stosb
movq %rsi,%rcx /* zero by words */
shrq $3,%rcx
andq $7,%rsi
rep
stosq
L1: movq %rsi,%rcx /* zero remainder by bytes */
rep
stosb
ret
END(bzero)
.section .note.GNU-stack,"",%progbits