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/*
* 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>
ENTRY(memset)
movq %rsi,%rax
movq %rdx,%rcx
movq %rdi,%r11
cld /* set fill direction forward */
/*
* if the string is too short, it's really not worth the overhead
* of aligning to word boundaries, etc. So we jump to a plain
* unaligned set.
*/
cmpq $0x0f,%rcx
jle L1
movb %al,%ah /* copy char to all bytes in word */
movl %eax,%edx
sall $16,%eax
orl %edx,%eax
movl %eax,%edx
salq $32,%rax
orq %rdx,%rax
movq %rdi,%rdx /* compute misalignment */
negq %rdx
andq $7,%rdx
movq %rcx,%r8
subq %rdx,%r8
movq %rdx,%rcx /* set until word aligned */
rep
stosb
movq %r8,%rcx
shrq $3,%rcx /* set by words */
rep
stosq
movq %r8,%rcx /* set remainder by bytes */
andq $7,%rcx
L1: rep
stosb
movq %r11,%rax
ret
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