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/*
 *  linux/arch/arm/lib/memset.S
 *
 *  Copyright (C) 1995-2000 Russell King
 *
 * 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.
 *
 *  ASM optimised string functions
 */
#include <linux/linkage.h>
#include <asm/assembler.h>

        .text
        .align  5
        .word   0

1:      subs    r2, r2, #4              @ 1 do we have enough
        blt     5f                      @ 1 bytes to align with?
        cmp     r3, #2                  @ 1
        strltb  r1, [r0], #1            @ 1
        strleb  r1, [r0], #1            @ 1
        strb    r1, [r0], #1            @ 1
        add     r2, r2, r3              @ 1 (r2 = r2 - (4 - r3))
/*
 * The pointer is now aligned and the length is adjusted.  Try doing the
 * memzero again.
 */

ENTRY(memset)
        ands    r3, r0, #3              @ 1 unaligned?
        bne     1b                      @ 1
/*
 * we know that the pointer in r0 is aligned to a word boundary.
 */
        orr     r1, r1, r1, lsl #8
        orr     r1, r1, r1, lsl #16
        mov     r3, r1
        cmp     r2, #16
        blt     4f
/*
 * We need an extra register for this loop - save the return address and
 * use the LR
 */
        str     lr, [sp, #-4]!
        mov     ip, r1
        mov     lr, r1

2:      subs    r2, r2, #64
        stmgeia r0!, {r1, r3, ip, lr}   @ 64 bytes at a time.
        stmgeia r0!, {r1, r3, ip, lr}
        stmgeia r0!, {r1, r3, ip, lr}
        stmgeia r0!, {r1, r3, ip, lr}
        bgt     2b
        LOADREGS(eqfd, sp!, {pc})       @ Now <64 bytes to go.
/*
 * No need to correct the count; we're only testing bits from now on
 */
        tst     r2, #32
        stmneia r0!, {r1, r3, ip, lr}
        stmneia r0!, {r1, r3, ip, lr}
        tst     r2, #16
        stmneia r0!, {r1, r3, ip, lr}
        ldr     lr, [sp], #4

4:      tst     r2, #8
        stmneia r0!, {r1, r3}
        tst     r2, #4
        strne   r1, [r0], #4
/*
 * When we get here, we've got less than 4 bytes to zero.  We
 * may have an unaligned pointer as well.
 */
5:      tst     r2, #2
        strneb  r1, [r0], #1
        strneb  r1, [r0], #1
        tst     r2, #1
        strneb  r1, [r0], #1
        RETINSTR(mov,pc,lr)