io-readsb.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.
*/
.text
.Lnot_word_aligned:
1: ld.ub r8, r12[0]
sub r10, 1
st.b r11++, r8
reteq r12
tst r11, r9
brne 1b
/* fall through */
.global __raw_readsb
.type __raw_readsb,@function
__raw_readsb:
cp.w r10, 0
mov r9, 3
reteq r12
tst r11, r9
brne .Lnot_word_aligned
sub r10, 4
brlt 2f
1: ldins.b r8:t, r12[0]
ldins.b r8:u, r12[0]
ldins.b r8:l, r12[0]
ldins.b r8:b, r12[0]
st.w r11++, r8
sub r10, 4
brge 1b
2: sub r10, -4
reteq r12
3: ld.ub r8, r12[0]
sub r10, 1
st.b r11++, r8
brne 3b
retal r12