124 строки
2.4 KiB
ArmAsm
124 строки
2.4 KiB
ArmAsm
/*
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* linux/arch/arm/lib/io-readsb.S
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*
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* Copyright (C) 1995-2000 Russell King
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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.Linsb_align: rsb ip, ip, #4
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cmp ip, r2
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movgt ip, r2
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cmp ip, #2
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ldrb r3, [r0]
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strb r3, [r1], #1
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ldrgeb r3, [r0]
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strgeb r3, [r1], #1
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ldrgtb r3, [r0]
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strgtb r3, [r1], #1
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subs r2, r2, ip
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bne .Linsb_aligned
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ENTRY(__raw_readsb)
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teq r2, #0 @ do we have to check for the zero len?
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reteq lr
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ands ip, r1, #3
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bne .Linsb_align
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.Linsb_aligned: stmfd sp!, {r4 - r6, lr}
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subs r2, r2, #16
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bmi .Linsb_no_16
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.Linsb_16_lp: ldrb r3, [r0]
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ldrb r4, [r0]
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ldrb r5, [r0]
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mov r3, r3, put_byte_0
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ldrb r6, [r0]
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orr r3, r3, r4, put_byte_1
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ldrb r4, [r0]
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orr r3, r3, r5, put_byte_2
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ldrb r5, [r0]
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orr r3, r3, r6, put_byte_3
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ldrb r6, [r0]
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mov r4, r4, put_byte_0
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ldrb ip, [r0]
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orr r4, r4, r5, put_byte_1
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ldrb r5, [r0]
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orr r4, r4, r6, put_byte_2
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ldrb r6, [r0]
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orr r4, r4, ip, put_byte_3
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ldrb ip, [r0]
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mov r5, r5, put_byte_0
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ldrb lr, [r0]
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orr r5, r5, r6, put_byte_1
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ldrb r6, [r0]
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orr r5, r5, ip, put_byte_2
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ldrb ip, [r0]
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orr r5, r5, lr, put_byte_3
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ldrb lr, [r0]
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mov r6, r6, put_byte_0
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orr r6, r6, ip, put_byte_1
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ldrb ip, [r0]
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orr r6, r6, lr, put_byte_2
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orr r6, r6, ip, put_byte_3
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stmia r1!, {r3 - r6}
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subs r2, r2, #16
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bpl .Linsb_16_lp
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tst r2, #15
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ldmeqfd sp!, {r4 - r6, pc}
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.Linsb_no_16: tst r2, #8
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beq .Linsb_no_8
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ldrb r3, [r0]
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ldrb r4, [r0]
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ldrb r5, [r0]
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mov r3, r3, put_byte_0
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ldrb r6, [r0]
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orr r3, r3, r4, put_byte_1
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ldrb r4, [r0]
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orr r3, r3, r5, put_byte_2
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ldrb r5, [r0]
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orr r3, r3, r6, put_byte_3
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ldrb r6, [r0]
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mov r4, r4, put_byte_0
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ldrb ip, [r0]
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orr r4, r4, r5, put_byte_1
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orr r4, r4, r6, put_byte_2
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orr r4, r4, ip, put_byte_3
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stmia r1!, {r3, r4}
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.Linsb_no_8: tst r2, #4
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beq .Linsb_no_4
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ldrb r3, [r0]
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ldrb r4, [r0]
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ldrb r5, [r0]
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ldrb r6, [r0]
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mov r3, r3, put_byte_0
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orr r3, r3, r4, put_byte_1
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orr r3, r3, r5, put_byte_2
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orr r3, r3, r6, put_byte_3
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str r3, [r1], #4
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.Linsb_no_4: ands r2, r2, #3
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ldmeqfd sp!, {r4 - r6, pc}
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cmp r2, #2
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ldrb r3, [r0]
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strb r3, [r1], #1
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ldrgeb r3, [r0]
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strgeb r3, [r1], #1
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ldrgtb r3, [r0]
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strgtb r3, [r1]
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ldmfd sp!, {r4 - r6, pc}
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ENDPROC(__raw_readsb)
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