io-readsl.S
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/*
* linux/arch/arm/lib/io-readsl.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.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
ENTRY(__raw_readsl)
teq r2, #0 @ do we have to check for the zero len?
moveq pc, lr
ands ip, r1, #3
bne 3f
subs r2, r2, #4
bmi 2f
stmfd sp!, {r4, lr}
1: ldr r3, [r0, #0]
ldr r4, [r0, #0]
ldr ip, [r0, #0]
ldr lr, [r0, #0]
subs r2, r2, #4
stmia r1!, {r3, r4, ip, lr}
bpl 1b
ldmfd sp!, {r4, lr}
2: movs r2, r2, lsl #31
ldrcs r3, [r0, #0]
ldrcs ip, [r0, #0]
stmcsia r1!, {r3, ip}
ldrne r3, [r0, #0]
strne r3, [r1, #0]
mov pc, lr
3: ldr r3, [r0]
cmp ip, #2
mov ip, r3, get_byte_0
strb ip, [r1], #1
bgt 6f
mov ip, r3, get_byte_1
strb ip, [r1], #1
beq 5f
mov ip, r3, get_byte_2
strb ip, [r1], #1
4: subs r2, r2, #1
mov ip, r3, pull #24
ldrne r3, [r0]
orrne ip, ip, r3, push #8
strne ip, [r1], #4
bne 4b
b 8f
5: subs r2, r2, #1
mov ip, r3, pull #16
ldrne r3, [r0]
orrne ip, ip, r3, push #16
strne ip, [r1], #4
bne 5b
b 7f
6: subs r2, r2, #1
mov ip, r3, pull #8
ldrne r3, [r0]
orrne ip, ip, r3, push #24
strne ip, [r1], #4
bne 6b
mov r3, ip, get_byte_2
strb r3, [r1, #2]
7: mov r3, ip, get_byte_1
strb r3, [r1, #1]
8: mov r3, ip, get_byte_0
strb r3, [r1, #0]
mov pc, lr
ENDPROC(__raw_readsl)