io-readsw.S
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/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* 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.
*/
.Lnot_word_aligned:
/*
* Bad alignment will cause a hardware exception, which is as
* good as anything. No need for us to check for proper alignment.
*/
ld.uh r8, r12[0]
sub r10, 1
st.h r11++, r8
/* fall through */
.global __raw_readsw
.type __raw_readsw,@function
__raw_readsw:
cp.w r10, 0
reteq r12
mov r9, 3
tst r11, r9
brne .Lnot_word_aligned
sub r10, 2
brlt 2f
1: ldins.h r8:t, r12[0]
ldins.h r8:b, r12[0]
st.w r11++, r8
sub r10, 2
brge 1b
2: sub r10, -2
reteq r12
ld.uh r8, r12[0]
st.h r11++, r8
retal r12