linux-vybrid_public/arch/arm64/lib/memset.S

/*
 * Copyright (C) 2013 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/linkage.h>
#include <asm/assembler.h>

/*
 * Fill in the buffer with character c (alignment handled by the hardware)
 *
 * Parameters:
 *	x0 - buf
 *	x1 - c
 *	x2 - n
 * Returns:
 *	x0 - buf
 */
ENTRY(memset)
	mov	x4, x0
	and	w1, w1, #0xff
	orr	w1, w1, w1, lsl #8
	orr	w1, w1, w1, lsl #16
	orr	x1, x1, x1, lsl #32
	subs	x2, x2, #8
	b.mi	2f
1:	str	x1, [x4], #8
	subs	x2, x2, #8
	b.pl	1b
2:	adds	x2, x2, #4
	b.mi	3f
	sub	x2, x2, #4
	str	w1, [x4], #4
3:	adds	x2, x2, #2
	b.mi	4f
	sub	x2, x2, #2
	strh	w1, [x4], #2
4:	adds	x2, x2, #1
	b.mi	5f
	strb	w1, [x4]
5:	ret
ENDPROC(memset)