clear_page.s

linux-2.4.29操作系统的源码

/*
 * Zero a page. 	
 * rdi	page
 */			
	.globl clear_page
	.p2align 4
clear_page:
	xorl   %eax,%eax
	movl   $4096/64,%ecx
	.p2align 4
.Lloop:
	decl	%ecx
#define PUT(x) movq %rax,x*8(%rdi) 
	movq %rax,(%rdi)
	PUT(1)
	PUT(2)
	PUT(3)
	PUT(4)
	PUT(5)
	PUT(6)
	PUT(7)
	leaq	64(%rdi),%rdi
	jnz	.Lloop
	nop
	ret