69 lines
1.3 KiB
ArmAsm
69 lines
1.3 KiB
ArmAsm
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/* memxor.S */
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/*
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This file is part of the Crypto-avr-lib/microcrypt-lib.
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Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
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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 as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* File: memxor.S
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* Author: Daniel Otte
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* Date: 2008-08-07
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* License: GPLv3 or later
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* Description: memxor, XORing one block into another
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*
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*/
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/*
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* void memxor(void* dest, const void* src, uint16_t n);
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*/
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/*
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* param dest is passed in r24:r25
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* param src is passed in r22:r23
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* param n is passed in r20:r21
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*/
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.global memxor
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memxor:
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movw r30, r24
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movw r26, r22
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movw r24, r20
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tst r24
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brne 1f
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tst r25
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breq 2f
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1:
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ld r20, X+
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ld r21, Z
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eor r20, r21
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st Z+, r20
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sbiw r24, 1
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brne 1b
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2:
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ret
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