rockbox/lib/rbcodec/codecs/demac/libdemac/predictor-cf.S

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/*
libdemac - A Monkey's Audio decoder
$Id$
Copyright (C) Dave Chapman 2007
Coldfire predictor copyright (C) 2007 Jens Arnold
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
*/
#include "demac_config.h"
/* NOTE: The following need to be kept in sync with parser.h */
#define YDELAYA 200
#define YDELAYB 168
#define XDELAYA 136
#define XDELAYB 104
#define YADAPTCOEFFSA 72
#define XADAPTCOEFFSA 56
#define YADAPTCOEFFSB 40
#define XADAPTCOEFFSB 20
/* struct predictor_t members: */
#define buf 0 /* int32_t* buf */
#define YlastA 4 /* int32_t YlastA; */
#define XlastA 8 /* int32_t XlastA; */
#define YfilterB 12 /* int32_t YfilterB; */
#define XfilterA 16 /* int32_t XfilterA; */
#define XfilterB 20 /* int32_t XfilterB; */
#define YfilterA 24 /* int32_t YfilterA; */
#define YcoeffsA 28 /* int32_t YcoeffsA[4]; */
#define XcoeffsA 44 /* int32_t XcoeffsA[4]; */
#define YcoeffsB 60 /* int32_t YcoeffsB[5]; */
#define XcoeffsB 80 /* int32_t XcoeffsB[5]; */
#define historybuffer 100 /* int32_t historybuffer[] */
.text
.align 2
.global predictor_decode_stereo
.type predictor_decode_stereo,@function
| void predictor_decode_stereo(struct predictor_t* p,
| int32_t* decoded0,
| int32_t* decoded1,
| int count)
predictor_decode_stereo:
lea.l (-12*4,%sp), %sp
movem.l %d2-%d7/%a2-%a6, (4,%sp)
movem.l (12*4+8,%sp), %a3-%a5 | %a3 = decoded0
| %a4 = decoded1
move.l %a5, (%sp) | (%sp) = count
move.l #0, %macsr | signed integer mode
move.l (12*4+4,%sp), %a6 | %a6 = p
move.l (%a6), %a5 | %a5 = p->buf
.loop:
| ***** PREDICTOR Y *****
| Predictor Y, Filter A
move.l (YlastA,%a6), %d3 | %d3 = p->YlastA
movem.l (YDELAYA-12,%a5), %d0-%d2 | %d0 = p->buf[YDELAYA-3]
| %d1 = p->buf[YDELAYA-2]
| %d2 = p->buf[YDELAYA-1]
move.l %d3, (YDELAYA,%a5) | p->buf[YDELAYA] = %d3
sub.l %d3, %d2
neg.l %d2 | %d2 = %d3 - %d2
move.l %d2, (YDELAYA-4,%a5) | p->buf[YDELAYA-1] = %d2
movem.l (YcoeffsA,%a6), %d4-%d7 | %d4 = p->YcoeffsA[0]
| %d5 = p->YcoeffsA[1]
| %d6 = p->YcoeffsA[2]
| %d7 = p->YcoeffsA[3]
mac.l %d3, %d4, %acc0 | %acc0 = p->buf[YDELAYA] * p->YcoeffsA[0]
mac.l %d2, %d5, %acc0 | %acc0 += p->buf[YDELAYA-1] * p->YcoeffsA[1]
mac.l %d1, %d6, %acc0 | %acc0 += p->buf[YDELAYA-2] * p->YcoeffsA[2]
mac.l %d0, %d7, %acc0 | %acc0 += p->buf[YDELAYA-3] * p->YcoeffsA[3]
tst.l %d2
beq.s 1f
spl.b %d2 | pos: 0x??????ff, neg: 0x??????00
extb.l %d2 | pos: 0xffffffff, neg: 0x00000000
or.l #1, %d2 | pos: 0xffffffff, neg: 0x00000001
1: | %d2 = SIGN(%d2)
move.l %d2, (YADAPTCOEFFSA-4,%a5) | p->buf[YADAPTCOEFFSA-1] = %d2
tst.l %d3
beq.s 1f
spl.b %d3
extb.l %d3
or.l #1, %d3
1: | %d3 = SIGN(%d3)
move.l %d3, (YADAPTCOEFFSA,%a5) | p->buf[YADAPTCOEFFSA] = %d3
| Predictor Y, Filter B
movem.l (YfilterB,%a6), %d2-%d3 | %d2 = p->YfilterB
| %d3 = p->XfilterA
move.l %d3, (YfilterB,%a6) | p->YfilterB = %d3
move.l %d2, %d1 | %d1 = %d2
lsl.l #5, %d2 | %d2 = %d2 * 32
sub.l %d1, %d2 | %d2 -= %d1 (== 31 * old_d2)
asr.l #5, %d2 | %d2 >>= 5
sub.l %d2, %d3 | %d3 -= %d2
movem.l (YDELAYB-16,%a5), %d4-%d7 | %d4 = p->buf[YDELAYB-4]
| %d5 = p->buf[YDELAYB-3]
| %d6 = p->buf[YDELAYB-2]
| %d7 = p->buf[YDELAYB-1]
sub.l %d3, %d7
neg.l %d7 | %d7 = %d3 - %d7
move.l %d7, (YDELAYB-4,%a5) | p->buf[YDELAYB-1] = %d7
movem.l (YcoeffsB,%a6), %d1-%d2/%a0-%a2 | %d1 = p->YcoeffsB[0]
| %d2 = p->YcoeffsB[1]
| %a0 = p->YcoeffsB[2]
| %a1 = p->YcoeffsB[3]
| %a2 = p->YcoeffsB[4]
mac.l %d3, %d1, %acc1 | %acc1 = p->buf[YDELAYB] * p->YcoeffsB[0]
mac.l %d7, %d2, %acc1 | %acc1 += p->buf[YDELAYB-1] * p->YcoeffsB[1]
mac.l %d6, %a0, %acc1 | %acc1 += p->buf[YDELAYB-2] * p->YcoeffsB[2]
mac.l %d5, %a1, %acc1 | %acc1 += p->buf[YDELAYB-3] * p->YcoeffsB[3]
mac.l %d4, %a2, %acc1 | %acc1 += p->buf[YDELAYB-4] * p->YcoeffsB[4]
move.l %d3, (YDELAYB, %a5) | p->buf[YDELAYB] = %d3
tst.l %d7
beq.s 1f
spl.b %d7
extb.l %d7
or.l #1, %d7
1: | %d7 = SIGN(%d7)
move.l %d7, (YADAPTCOEFFSB-4,%a5) | p->buf[YADAPTCOEFFSB-1] = %d7
tst.l %d3
beq.s 1f
spl.b %d3
extb.l %d3
or.l #1, %d3
1: | %d3 = SIGN(%d3)
move.l %d3, (YADAPTCOEFFSB, %a5) | p->buf[YADAPTCOEFFSB] = %d3
| %d1, %d2, %a0, %a1, %a2 contain p->YcoeffsB[0..4]
| %d7, %d3 contain p->buf[YADAPTCOEFFSB-1] and p->buf[YADAPTCOEFFSB]
move.l (%a3), %d0 | %d0 = *decoded0
beq.s 3f
movem.l (YADAPTCOEFFSB-16,%a5), %d4-%d6 | %d4 = p->buf[YADAPTCOEFFSB-4]
| %d5 = p->buf[YADAPTCOEFFSB-3]
| %d6 = p->buf[YADAPTCOEFFSB-2]
bmi.s 1f | flags still valid here
| *decoded0 > 0
sub.l %d3, %d1 | %d1 = p->YcoeffsB[0] - p->buf[YADAPTCOEFFSB]
sub.l %d7, %d2 | %d2 = p->YcoeffsB[1] - p->buf[YADAPTCOEFFSB-1]
sub.l %d6, %a0 | %a0 = p->YcoeffsB[2] - p->buf[YADAPTCOEFFSB-2]
sub.l %d5, %a1 | %a1 = p->YcoeffsB[3] - p->buf[YADAPTCOEFFSB-3]
sub.l %d4, %a2 | %a2 = p->YcoeffsB[4] - p->buf[YADAPTCOEFFSB-4]
movem.l %d1-%d2/%a0-%a2, (YcoeffsB,%a6) | Save p->YcoeffsB[]
movem.l (YcoeffsA,%a6), %d4-%d7 | %d4 = p->YcoeffsA[0]
| %d5 = p->YcoeffsA[1]
| %d6 = p->YcoeffsA[2]
| %d7 = p->YcoeffsA[3]
movem.l (YADAPTCOEFFSA-12,%a5), %d2/%a0-%a2
| %d2 = p->buf[YADAPTCOEFFSA-3]
| %a0 = p->buf[YADAPTCOEFFSA-2]
| %a1 = p->buf[YADAPTCOEFFSA-1]
| %a2 = p->buf[YADAPTCOEFFSA]
sub.l %a2, %d4 | %d4 = p->YcoeffsA[0] - p->buf[YADAPTCOEFFSA]
sub.l %a1, %d5 | %d5 = p->YcoeffsA[1] - p->buf[YADAPTCOEFFSA-1]
sub.l %a0, %d6 | %d6 = p->YcoeffsA[2] - p->buf[YADAPTCOEFFSA-2]
sub.l %d2, %d7 | %d7 = p->YcoeffsA[3] - p->buf[YADAPTCOEFFSA-3]
bra.s 2f
1: | *decoded0 < 0
add.l %d3, %d1 | %d1 = p->YcoeffsB[0] + p->buf[YADAPTCOEFFSB]
add.l %d7, %d2 | %d2 = p->YcoeffsB[1] + p->buf[YADAPTCOEFFSB-1]
add.l %d6, %a0 | %a0 = p->YcoeffsB[2] + p->buf[YADAPTCOEFFSB-2]
add.l %d5, %a1 | %a1 = p->YcoeffsB[3] + p->buf[YADAPTCOEFFSB-3]
add.l %d4, %a2 | %a2 = p->YcoeffsB[4] + p->buf[YADAPTCOEFFSB-4]
movem.l %d1-%d2/%a0-%a2, (YcoeffsB,%a6) | Save p->YcoeffsB[]
movem.l (YcoeffsA,%a6), %d4-%d7 | %d4 = p->YcoeffsA[0]
| %d5 = p->YcoeffsA[1]
| %d6 = p->YcoeffsA[2]
| %d7 = p->YcoeffsA[3]
movem.l (YADAPTCOEFFSA-12,%a5), %d2/%a0-%a2
| %d2 = p->buf[YADAPTCOEFFSA-3]
| %a0 = p->buf[YADAPTCOEFFSA-2]
| %a1 = p->buf[YADAPTCOEFFSA-1]
| %a2 = p->buf[YADAPTCOEFFSA]
add.l %a2, %d4 | %d4 = p->YcoeffsA[0] + p->buf[YADAPTCOEFFSA]
add.l %a1, %d5 | %d5 = p->YcoeffsA[1] + p->buf[YADAPTCOEFFSA-1]
add.l %a0, %d6 | %d6 = p->YcoeffsA[2] + p->buf[YADAPTCOEFFSA-2]
add.l %d2, %d7 | %d7 = p->YcoeffsA[3] + p->buf[YADAPTCOEFFSA-3]
2:
movem.l %d4-%d7, (YcoeffsA,%a6) | Save p->YcoeffsA[]
3:
| Finish Predictor Y
movclr.l %acc0, %d1 | %d1 = predictionA
movclr.l %acc1, %d2 | %d2 = predictionB
asr.l #1, %d2
add.l %d2, %d1 | %d1 += (%d2 >> 1)
asr.l #8, %d1
asr.l #2, %d1 | %d1 >>= 10
add.l %d0, %d1 | %d1 += %d0
move.l %d1, (YlastA,%a6) | p->YlastA = %d1
move.l (YfilterA,%a6), %d2 | %d2 = p->YfilterA
move.l %d2, %d0
lsl.l #5, %d2
sub.l %d0, %d2 | %d2 = 31 * %d2
asr.l #5, %d2 | %d2 >>= 5
add.l %d1, %d2
move.l %d2, (YfilterA,%a6) | p->YfilterA = %d2
| *decoded0 stored 2 instructions down, avoiding pipeline stall
| ***** PREDICTOR X *****
| Predictor X, Filter A
move.l (XlastA,%a6), %d3 | %d3 = p->XlastA
move.l %d2, (%a3)+ | *(decoded0++) = %d2 (p->YfilterA)
movem.l (XDELAYA-12,%a5), %d0-%d2 | %d0 = p->buf[XDELAYA-3]
| %d1 = p->buf[XDELAYA-2]
| %d2 = p->buf[XDELAYA-1]
move.l %d3, (XDELAYA,%a5) | p->buf[XDELAYA] = %d3
sub.l %d3, %d2
neg.l %d2 | %d2 = %d3 -%d2
move.l %d2, (XDELAYA-4,%a5) | p->buf[XDELAYA-1] = %d2
movem.l (XcoeffsA,%a6), %d4-%d7 | %d4 = p->XcoeffsA[0]
| %d5 = p->XcoeffsA[1]
| %d6 = p->XcoeffsA[2]
| %d7 = p->XcoeffsA[3]
mac.l %d3, %d4, %acc0 | %acc0 = p->buf[XDELAYA] * p->XcoeffsA[0]
mac.l %d2, %d5, %acc0 | %acc0 += p->buf[XDELAYA-1] * p->XcoeffsA[1]
mac.l %d1, %d6, %acc0 | %acc0 += p->buf[XDELAYA-2] * p->XcoeffsA[2]
mac.l %d0, %d7, %acc0 | %acc0 += p->buf[XDELAYA-3] * p->XcoeffsA[3]
tst.l %d2
beq.s 1f
spl.b %d2 | pos: 0x??????ff, neg: 0x??????00
extb.l %d2 | pos: 0xffffffff, neg: 0x00000000
or.l #1, %d2 | pos: 0xffffffff, neg: 0x00000001
1: | %d2 = SIGN(%d2)
move.l %d2, (XADAPTCOEFFSA-4,%a5) | p->buf[XADAPTCOEFFSA-1] = %d2
tst.l %d3
beq.s 1f
spl.b %d3
extb.l %d3
or.l #1, %d3
1: | %d3 = SIGN(%d3)
move.l %d3, (XADAPTCOEFFSA,%a5) | p->buf[XADAPTCOEFFSA] = %d3
| Predictor X, Filter B
movem.l (XfilterB,%a6), %d2-%d3 | %d2 = p->XfilterB
| %d3 = p->YfilterA
move.l %d3, (XfilterB,%a6) | p->XfilterB = %d3
move.l %d2, %d1 | %d1 = %d2
lsl.l #5, %d2 | %d2 = %d2 * 32
sub.l %d1, %d2 | %d2 -= %d1 (== 31 * old_d2)
asr.l #5, %d2 | %d2 >>= 5
sub.l %d2, %d3 | %d3 -= %d2
movem.l (XDELAYB-16,%a5), %d4-%d7 | %d4 = p->buf[XDELAYB-4]
| %d5 = p->buf[XDELAYB-3]
| %d6 = p->buf[XDELAYB-2]
| %d7 = p->buf[XDELAYB-1]
sub.l %d3, %d7
neg.l %d7 | %d7 = %d3 - %d7
move.l %d7, (XDELAYB-4,%a5) | p->buf[XDELAYB-1] = %d7
movem.l (XcoeffsB,%a6), %d1-%d2/%a0-%a2 | %d1 = p->XcoeffsB[0]
| %d2 = p->XcoeffsB[1]
| %a0 = p->XcoeffsB[2]
| %a1 = p->XcoeffsB[3]
| %a2 = p->XcoeffsB[4]
mac.l %d3, %d1, %acc1 | %acc1 = p->buf[XDELAYB] * p->XcoeffsB[0]
mac.l %d7, %d2, %acc1 | %acc1 += p->buf[XDELAYB-1] * p->XcoeffsB[1]
mac.l %d6, %a0, %acc1 | %acc1 += p->buf[XDELAYB-2] * p->XcoeffsB[2]
mac.l %d5, %a1, %acc1 | %acc1 += p->buf[XDELAYB-3] * p->XcoeffsB[3]
mac.l %d4, %a2, %acc1 | %acc1 += p->buf[XDELAYB-4] * p->XcoeffsB[4]
move.l %d3, (XDELAYB, %a5) | p->buf[XDELAYB] = %d3
tst.l %d7
beq.s 1f
spl.b %d7
extb.l %d7
or.l #1, %d7
1: | %d7 = SIGN(%d7)
move.l %d7, (XADAPTCOEFFSB-4,%a5) | p->buf[XADAPTCOEFFSB-1] = %d7
tst.l %d3
beq.s 1f
spl.b %d3
extb.l %d3
or.l #1, %d3
1: | %d3 = SIGN(%d3)
move.l %d3, (XADAPTCOEFFSB, %a5) | p->buf[XADAPTCOEFFSB] = %d3
| %d1, %d2, %a0, %a1, %a2 contain p->XcoeffsB[0..4]
| %d7, %d3 contain p->buf[XADAPTCOEFFSB-1] and p->buf[XADAPTCOEFFSB]
move.l (%a4), %d0 | %d0 = *decoded1
beq.s 3f
movem.l (XADAPTCOEFFSB-16,%a5), %d4-%d6 | %d4 = p->buf[XADAPTCOEFFSB-4]
| %d5 = p->buf[XADAPTCOEFFSB-3]
| %d6 = p->buf[XADAPTCOEFFSB-2]
bmi.s 1f | flags still valid here
| *decoded1 > 0
sub.l %d3, %d1 | %d1 = p->XcoeffsB[0] - p->buf[XADAPTCOEFFSB]
sub.l %d7, %d2 | %d2 = p->XcoeffsB[1] - p->buf[XADAPTCOEFFSB-1]
sub.l %d6, %a0 | %a0 = p->XcoeffsB[2] - p->buf[XADAPTCOEFFSB-2]
sub.l %d5, %a1 | %a1 = p->XcoeffsB[3] - p->buf[XADAPTCOEFFSB-3]
sub.l %d4, %a2 | %a2 = p->XcoeffsB[4] - p->buf[XADAPTCOEFFSB-4]
movem.l %d1-%d2/%a0-%a2, (XcoeffsB,%a6) | Save p->XcoeffsB[]
movem.l (XcoeffsA,%a6), %d4-%d7 | %d4 = p->XcoeffsA[0]
| %d5 = p->XcoeffsA[1]
| %d6 = p->XcoeffsA[2]
| %d7 = p->XcoeffsA[3]
movem.l (XADAPTCOEFFSA-12,%a5), %d2/%a0-%a2
| %d2 = p->buf[XADAPTCOEFFSA-3]
| %a0 = p->buf[XADAPTCOEFFSA-2]
| %a1 = p->buf[XADAPTCOEFFSA-1]
| %a2 = p->buf[XADAPTCOEFFSA]
sub.l %a2, %d4 | %d4 = p->XcoeffsA[0] - p->buf[XADAPTCOEFFSA]
sub.l %a1, %d5 | %d5 = p->XcoeffsA[1] - p->buf[XADAPTCOEFFSA-1]
sub.l %a0, %d6 | %d6 = p->XcoeffsA[2] - p->buf[XADAPTCOEFFSA-2]
sub.l %d2, %d7 | %d7 = p->XcoeffsA[3] - p->buf[XADAPTCOEFFSA-3]
bra.s 2f
1: | *decoded1 < 0
add.l %d3, %d1 | %d1 = p->XcoeffsB[0] + p->buf[XADAPTCOEFFSB]
add.l %d7, %d2 | %d2 = p->XcoeffsB[1] + p->buf[XADAPTCOEFFSB-1]
add.l %d6, %a0 | %a0 = p->XcoeffsB[2] + p->buf[XADAPTCOEFFSB-2]
add.l %d5, %a1 | %a1 = p->XcoeffsB[3] + p->buf[XADAPTCOEFFSB-3]
add.l %d4, %a2 | %a2 = p->XcoeffsB[4] + p->buf[XADAPTCOEFFSB-4]
movem.l %d1-%d2/%a0-%a2, (XcoeffsB,%a6) | Save p->XcoeffsB[]
movem.l (XcoeffsA,%a6), %d4-%d7 | %d4 = p->XcoeffsA[0]
| %d5 = p->XcoeffsA[1]
| %d6 = p->XcoeffsA[2]
| %d7 = p->XcoeffsA[3]
movem.l (XADAPTCOEFFSA-12,%a5), %d2/%a0-%a2
| %d2 = p->buf[XADAPTCOEFFSA-3]
| %a0 = p->buf[XADAPTCOEFFSA-2]
| %a1 = p->buf[XADAPTCOEFFSA-1]
| %a2 = p->buf[XADAPTCOEFFSA]
add.l %a2, %d4 | %d4 = p->XcoeffsA[0] + p->buf[XADAPTCOEFFSA]
add.l %a1, %d5 | %d5 = p->XcoeffsA[1] + p->buf[XADAPTCOEFFSA-1]
add.l %a0, %d6 | %d6 = p->XcoeffsA[2] + p->buf[XADAPTCOEFFSA-2]
add.l %d2, %d7 | %d7 = p->XcoeffsA[3] + p->buf[XADAPTCOEFFSA-3]
2:
movem.l %d4-%d7, (XcoeffsA,%a6) | Save p->XcoeffsA[]
3:
| Finish Predictor X
movclr.l %acc0, %d1 | %d1 = predictionA
movclr.l %acc1, %d2 | %d2 = predictionB
asr.l #1, %d2
add.l %d2, %d1 | %d1 += (%d2 >> 1)
asr.l #8, %d1
asr.l #2, %d1 | %d1 >>= 10
add.l %d0, %d1 | %d1 += %d0
move.l %d1, (XlastA,%a6) | p->XlastA = %d1
move.l (XfilterA,%a6), %d2 | %d2 = p->XfilterA
move.l %d2, %d0
lsl.l #5, %d2
sub.l %d0, %d2 | %d2 = 31 * %d2
asr.l #5, %d2 | %d6 >>= 2
add.l %d1, %d2
move.l %d2, (XfilterA,%a6) | p->XfilterA = %d2
| *decoded1 stored 3 instructions down, avoiding pipeline stall
| ***** COMMON *****
addq.l #4, %a5 | p->buf++
lea.l (historybuffer+PREDICTOR_HISTORY_SIZE*4,%a6), %a2
| %a2 = &p->historybuffer[PREDICTOR_HISTORY_SIZE]
move.l %d2, (%a4)+ | *(decoded1++) = %d2 (p->XfilterA)
cmp.l %a2, %a5
beq.s .move_hist | History buffer is full, we need to do a memmove
subq.l #1, (%sp) | decrease loop count
bne.w .loop
.done:
move.l %a5, (%a6) | Save value of p->buf
movem.l (4,%sp), %d2-%d7/%a2-%a6
lea.l (12*4,%sp), %sp
rts
.move_hist:
lea.l (historybuffer,%a6), %a2
| dest = %a2 (p->historybuffer)
| src = %a5 (p->buf)
| n = 200
movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes
movem.l %d0-%d7/%a0-%a1, (%a2)
movem.l (40,%a5), %d0-%d7/%a0-%a1 | 40 bytes
movem.l %d0-%d7/%a0-%a1, (40,%a2)
movem.l (80,%a5), %d0-%d7/%a0-%a1 | 40 bytes
movem.l %d0-%d7/%a0-%a1, (80,%a2)
movem.l (120,%a5), %d0-%d7/%a0-%a1 | 40 bytes
movem.l %d0-%d7/%a0-%a1, (120,%a2)
movem.l (160,%a5), %d0-%d7/%a0-%a1 | 40 bytes
movem.l %d0-%d7/%a0-%a1, (160,%a2)
move.l %a2, %a5 | p->buf = &p->historybuffer[0]
subq.l #1, (%sp) | decrease loop count
bne.w .loop
bra.s .done
.size predictor_decode_stereo, .-predictor_decode_stereo
.global predictor_decode_mono
.type predictor_decode_mono,@function
| void predictor_decode_mono(struct predictor_t* p,
| int32_t* decoded0,
| int count)
predictor_decode_mono:
lea.l (-11*4,%sp), %sp
movem.l %d2-%d7/%a2-%a6, (%sp)
move.l #0, %macsr | signed integer mode
move.l (11*4+4,%sp), %a6 | %a6 = p
move.l (11*4+8,%sp), %a4 | %a4 = decoded0
move.l (11*4+12,%sp), %d7 | %d7 = count
move.l (%a6), %a5 | %a5 = p->buf
move.l (YlastA,%a6), %d3 | %d3 = p->YlastA
.loopm:
| ***** PREDICTOR *****
movem.l (YDELAYA-12,%a5), %d0-%d2 | %d0 = p->buf[YDELAYA-3]
| %d1 = p->buf[YDELAYA-2]
| %d2 = p->buf[YDELAYA-1]
move.l %d3, (YDELAYA,%a5) | p->buf[YDELAYA] = %d3
sub.l %d3, %d2
neg.l %d2 | %d2 = %d3 - %d2
move.l %d2, (YDELAYA-4,%a5) | p->buf[YDELAYA-1] = %d2
movem.l (YcoeffsA,%a6), %a0-%a3 | %a0 = p->YcoeffsA[0]
| %a1 = p->YcoeffsA[1]
| %a2 = p->YcoeffsA[2]
| %a3 = p->YcoeffsA[3]
mac.l %d3, %a0, %acc0 | %acc0 = p->buf[YDELAYA] * p->YcoeffsA[0]
mac.l %d2, %a1, %acc0 | %acc0 += p->buf[YDELAYA-1] * p->YcoeffsA[1]
mac.l %d1, %a2, %acc0 | %acc0 += p->buf[YDELAYA-2] * p->YcoeffsA[2]
mac.l %d0, %a3, %acc0 | %acc0 += p->buf[YDELAYA-3] * p->YcoeffsA[3]
tst.l %d2
beq.s 1f
spl.b %d2 | pos: 0x??????ff, neg: 0x??????00
extb.l %d2 | pos: 0xffffffff, neg: 0x00000000
or.l #1, %d2 | pos: 0xffffffff, neg: 0x00000001
1: | %d2 = SIGN(%d2)
move.l %d2, (YADAPTCOEFFSA-4,%a5) | p->buf[YADAPTCOEFFSA-1] = %d2
tst.l %d3
beq.s 1f
spl.b %d3
extb.l %d3
or.l #1, %d3
1: | %d3 = SIGN(%d3)
move.l %d3, (YADAPTCOEFFSA,%a5) | p->buf[YADAPTCOEFFSA] = %d3
move.l (%a4), %d0 | %d0 = *decoded0
beq.s 3f
movem.l (YADAPTCOEFFSA-12,%a5),%d4-%d5 | %d4 = p->buf[YADAPTCOEFFSA-3]
| %d5 = p->buf[YADAPTCOEFFSA-2]
bmi.s 1f | flags still valid here
| *decoded0 > 0
sub.l %d3, %a0 | %a0 = p->YcoeffsA[0] - p->buf[YADAPTCOEFFSA]
sub.l %d2, %a1 | %a1 = p->YcoeffsA[1] - p->buf[YADAPTCOEFFSA-1]
sub.l %d5, %a2 | %a2 = p->YcoeffsA[2] - p->buf[YADAPTCOEFFSA-2]
sub.l %d4, %a3 | %a3 = p->YcoeffsA[3] - p->buf[YADAPTCOEFFSA-3]
bra.s 2f
1: | *decoded0 < 0
add.l %d3, %a0 | %a0 = p->YcoeffsA[0] - p->buf[YADAPTCOEFFSA]
add.l %d2, %a1 | %a1 = p->YcoeffsA[1] - p->buf[YADAPTCOEFFSA-1]
add.l %d5, %a2 | %a2 = p->YcoeffsA[2] - p->buf[YADAPTCOEFFSA-2]
add.l %d4, %a3 | %a3 = p->YcoeffsA[3] - p->buf[YADAPTCOEFFSA-3]
2:
movem.l %a0-%a3, (YcoeffsA,%a6) | save p->YcoeffsA[]
3:
| Finish Predictor
movclr.l %acc0, %d3 | %d3 = predictionA
asr.l #8, %d3
asr.l #2, %d3 | %d3 >>= 10
add.l %d0, %d3 | %d3 += %d0
move.l (YfilterA,%a6), %d2 | %d2 = p->YfilterA
move.l %d2, %d0
lsl.l #5, %d2
sub.l %d0, %d2 | %d2 = 31 * %d2
asr.l #5, %d2 | %d2 >>= 5
add.l %d3, %d2
move.l %d2, (YfilterA,%a6) | p->YfilterA = %d2
| *decoded0 stored 3 instructions down, avoiding pipeline stall
| ***** COMMON *****
addq.l #4, %a5 | p->buf++
lea.l (historybuffer+PREDICTOR_HISTORY_SIZE*4,%a6), %a3
| %a3 = &p->historybuffer[PREDICTOR_HISTORY_SIZE]
move.l %d2, (%a4)+ | *(decoded0++) = %d2 (p->YfilterA)
cmp.l %a3, %a5
beq.s .move_histm | History buffer is full, we need to do a memmove
subq.l #1, %d7 | decrease loop count
bne.w .loopm
move.l %d3, (YlastA,%a6) | %d3 = p->YlastA
.donem:
move.l %a5, (%a6) | Save value of p->buf
movem.l (%sp), %d2-%d7/%a2-%a6
lea.l (11*4,%sp), %sp
rts
.move_histm:
move.l %d3, (YlastA,%a6) | %d3 = p->YlastA
lea.l (historybuffer,%a6), %a3
| dest = %a3 (p->historybuffer)
| src = %a5 (p->buf)
| n = 200
movem.l (%a5), %d0-%d6/%a0-%a2 | 40 bytes
movem.l %d0-%d6/%a0-%a2, (%a3)
movem.l (40,%a5), %d0-%d6/%a0-%a2 | 40 bytes
movem.l %d0-%d6/%a0-%a2, (40,%a3)
movem.l (80,%a5), %d0-%d6/%a0-%a2 | 40 bytes
movem.l %d0-%d6/%a0-%a2, (80,%a3)
movem.l (120,%a5), %d0-%d6/%a0-%a2 | 40 bytes
movem.l %d0-%d6/%a0-%a2, (120,%a3)
movem.l (160,%a5), %d0-%d6/%a0-%a2 | 40 bytes
movem.l %d0-%d6/%a0-%a2, (160,%a3)
move.l %a3, %a5 | p->buf = &p->historybuffer[0]
move.l (YlastA,%a6), %d3 | %d3 = p->YlastA
subq.l #1, %d7 | decrease loop count
bne.w .loopm
bra.s .donem
.size predictor_decode_mono, .-predictor_decode_mono