/* 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 */ .text .align 2 .global predictor_decode_stereo .type predictor_decode_stereo,@function /* NOTE: The following need to be kept in sync with parser.h */ #define HISTORY_SIZE 512 #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[] */ | void predictor_decode_stereo(struct predictor_t* p, | int32_t* decoded0, | int32_t* decoded1, | int count) predictor_decode_stereo: lea.l (-14*4,%sp), %sp movem.l %d2-%d7/%a2-%a6, (3*4,%sp) movem.l (14*4+8,%sp), %d0-%d2 movem.l %d0-%d2, (%sp) | (%sp) = decoded0 | (4,%sp) = decoded1 | (8,%sp) = count move.l #0, %macsr | signed integer mode move.l (14*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] 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] move.l %d3, (YDELAYA,%a5) | p->buf[YDELAYA] = %d3 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 movclr.l %acc0, %d0 | NOTE: %d0 now contains predictionA - don't overwrite. | 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), %d2/%a0-%a3 | %d2 = p->YcoeffsB[0] | %a0 = p->YcoeffsB[1] | %a1 = p->YcoeffsB[2] | %a2 = p->YcoeffsB[3] | %a3 = p->YcoeffsB[4] mac.l %d3, %d2, %acc0 | %acc0 = p->buf[YDELAYB] * p->YcoeffsB[0] mac.l %d7, %a0, %acc0 | %acc0 += p->buf[YDELAYB-1] * p->YcoeffsB[1] mac.l %d6, %a1, %acc0 | %acc0 += p->buf[YDELAYB-2] * p->YcoeffsB[2] mac.l %d5, %a2, %acc0 | %acc0 += p->buf[YDELAYB-3] * p->YcoeffsB[3] mac.l %d4, %a3, %acc0 | %acc0 += 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 movclr.l %acc0, %d1 | %d0 still contains predictionA | %d1 contains predictionB | Finish Predictor Y move.l (%sp), %a4 | %a4 = decoded0 asr.l #1, %d1 add.l %d1, %d0 | %d0 += (%d1 >> 1) move.l (%a4), %d5 | %d5 = *decoded0 move.l %d5, %d1 | %d1 = %d5 asr.l #8, %d0 asr.l #2, %d0 | %d0 >>= 10 add.l %d0, %d1 | %d1 += %d0 move.l %d1, (YlastA,%a6) | p->YlastA = %d1 move.l (YfilterA,%a6), %d6 | %d6 = p->YfilterA move.l %d6, %d0 lsl.l #5, %d6 sub.l %d0, %d6 | %d6 = 31 * %d6 asr.l #5, %d6 | %d6 >>= 5 add.l %d6, %d1 move.l %d1, (YfilterA,%a6) | p->YfilterA = %d1 | %d1 contains p->YfilterA | %a4 contains decoded0 | %d5 contains *decoded0 | %d2, %a0, %a1, %a2, %a3 contain p->YcoeffsB[0..4] | %d7, %d3 contain p->buf[YADAPTCOEFFSB-1] and p->buf[YADAPTCOEFFSB] move.l %d1, (%a4)+ | *(decoded0++) = %d1 (p->YfilterA) move.l %a4, (%sp) | save decoded0 tst.l %d5 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, %d2 | %d2 = p->YcoeffsB[0] - p->buf[YADAPTCOEFFSB] sub.l %d7, %a0 | %a0 = p->YcoeffsB[1] - p->buf[YADAPTCOEFFSB-1] sub.l %d6, %a1 | %a1 = p->YcoeffsB[2] - p->buf[YADAPTCOEFFSB-2] sub.l %d5, %a2 | %a2 = p->YcoeffsB[3] - p->buf[YADAPTCOEFFSB-3] sub.l %d4, %a3 | %a3 = p->YcoeffsB[4] - p->buf[YADAPTCOEFFSB-4] movem.l %d2/%a0-%a3, (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, %d2 | %d2 = p->YcoeffsB[0] + p->buf[YADAPTCOEFFSB] add.l %d7, %a0 | %a0 = p->YcoeffsB[1] + p->buf[YADAPTCOEFFSB-1] add.l %d6, %a1 | %a1 = p->YcoeffsB[2] + p->buf[YADAPTCOEFFSB-2] add.l %d5, %a2 | %a2 = p->YcoeffsB[3] + p->buf[YADAPTCOEFFSB-3] add.l %d4, %a3 | %a3 = p->YcoeffsB[4] + p->buf[YADAPTCOEFFSB-4] movem.l %d2/%a0-%a3, (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: | ***** PREDICTOR X ***** | Predictor X, Filter A move.l (XlastA,%a6), %d3 | %d3 = p->XlastA movem.l (XDELAYA-12,%a5), %d0-%d2 | %d0 = p->buf[XDELAYA-3] | %d1 = p->buf[XDELAYA-2] | %d2 = p->buf[XDELAYA-1] 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), %a0-%a3 | %a0 = p->XcoeffsA[0] | %a1 = p->XcoeffsA[1] | %a2 = p->XcoeffsA[2] | %a3 = p->XcoeffsA[3] mac.l %d3, %a0, %acc0 | %acc0 = p->buf[XDELAYA] * p->XcoeffsA[0] mac.l %d2, %a1, %acc0 | %acc0 += p->buf[XDELAYA-1] * p->XcoeffsA[1] mac.l %d1, %a2, %acc0 | %acc0 += p->buf[XDELAYA-2] * p->XcoeffsA[2] mac.l %d0, %a3, %acc0 | %acc0 += p->buf[XDELAYA-3] * p->XcoeffsA[3] move.l %d3, (XDELAYA,%a5) | p->buf[XDELAYA] = %d3 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 movclr.l %acc0, %d0 | NOTE: %d0 now contains predictionA - don't overwrite. | 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), %d2/%a0-%a3 | %d2 = p->XcoeffsB[0] | %a0 = p->XcoeffsB[1] | %a1 = p->XcoeffsB[2] | %a2 = p->XcoeffsB[3] | %a3 = p->XcoeffsB[4] mac.l %d3, %d2, %acc0 | %acc0 = p->buf[XDELAYB] * p->XcoeffsB[0] mac.l %d7, %a0, %acc0 | %acc0 += p->buf[XDELAYB-1] * p->XcoeffsB[1] mac.l %d6, %a1, %acc0 | %acc0 += p->buf[XDELAYB-2] * p->XcoeffsB[2] mac.l %d5, %a2, %acc0 | %acc0 += p->buf[XDELAYB-3] * p->XcoeffsB[3] mac.l %d4, %a3, %acc0 | %acc0 += 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 movclr.l %acc0, %d1 | %d0 still contains predictionA | %d1 contains predictionB | Finish Predictor X move.l (4,%sp), %a4 | %a4 = decoded1 asr.l #1, %d1 add.l %d1, %d0 | %d0 += (%d1 >> 1) move.l (%a4), %d5 | %d5 = *decoded1 move.l %d5, %d1 | %d1 = %d5 asr.l #8, %d0 asr.l #2, %d0 | %d0 >>= 10 add.l %d0, %d1 | %d1 += %d0 move.l %d1, (XlastA,%a6) | p->XlastA = %d1 move.l (XfilterA,%a6), %d6 | %d6 = p->XfilterA move.l %d6, %d0 lsl.l #5, %d6 sub.l %d0, %d6 | %d6 = 31 * %d6 asr.l #5, %d6 | %d6 >>= 5 add.l %d6, %d1 move.l %d1, (XfilterA,%a6) | p->XfilterA = %d6 | %d1 contains p->XfilterA | %a4 contains decoded1 | %d5 contains *decoded1 | %d2, %a0, %a1, %a2, %a3 contain p->XcoeffsB[0..4] | %d7, %d3 contain p->buf[XADAPTCOEFFSB-1] and p->buf[XADAPTCOEFFSB] move.l %d1, (%a4)+ | *(decoded1++) = %d1 (p->XfilterA) move.l %a4, (4,%sp) | save decoded1 tst.l %d5 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, %d2 | %d2 = p->XcoeffsB[0] - p->buf[XADAPTCOEFFSB] sub.l %d7, %a0 | %a0 = p->XcoeffsB[1] - p->buf[XADAPTCOEFFSB-1] sub.l %d6, %a1 | %a1 = p->XcoeffsB[2] - p->buf[XADAPTCOEFFSB-2] sub.l %d5, %a2 | %a2 = p->XcoeffsB[3] - p->buf[XADAPTCOEFFSB-3] sub.l %d4, %a3 | %a3 = p->XcoeffsB[4] - p->buf[XADAPTCOEFFSB-4] movem.l %d2/%a0-%a3, (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, %d2 | %d2 = p->XcoeffsB[0] + p->buf[XADAPTCOEFFSB] add.l %d7, %a0 | %a0 = p->XcoeffsB[1] + p->buf[XADAPTCOEFFSB-1] add.l %d6, %a1 | %a1 = p->XcoeffsB[2] + p->buf[XADAPTCOEFFSB-2] add.l %d5, %a2 | %a2 = p->XcoeffsB[3] + p->buf[XADAPTCOEFFSB-3] add.l %d4, %a3 | %a3 = p->XcoeffsB[4] + p->buf[XADAPTCOEFFSB-4] movem.l %d2/%a0-%a3, (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: | ***** COMMON ***** addq.l #4, %a5 | p->buf++ lea.l (historybuffer+HISTORY_SIZE*4,%a6), %a3 | %a3 = &p->historybuffer[HISTORY_SIZE] cmp.l %a3, %a5 bne.s .endofloop | The history buffer is full, we need to do a memmove: lea.l (historybuffer,%a6), %a3 | dest = %a3 (p->historybuffer) | src = %a5 (p->buf) | n = 200 movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes lea.l (40,%a5), %a5 movem.l %d0-%d7/%a0-%a1, (%a3) lea.l (40,%a3), %a3 movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes lea.l (40,%a5), %a5 movem.l %d0-%d7/%a0-%a1, (%a3) lea.l (40,%a3), %a3 movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes lea.l (40,%a5), %a5 movem.l %d0-%d7/%a0-%a1, (%a3) lea.l (40,%a3), %a3 movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes lea.l (40,%a5), %a5 movem.l %d0-%d7/%a0-%a1, (%a3) lea.l (40,%a3), %a3 movem.l (%a5), %d0-%d7/%a0-%a1 | 40 bytes lea.l (40,%a5), %a5 movem.l %d0-%d7/%a0-%a1, (%a3) lea.l (40,%a3), %a3 lea.l (historybuffer,%a6), %a5 | p->buf = &p->historybuffer[0] .endofloop: subq.l #1, (8,%sp) | decrease loop count bne.w .loop move.l %a5, (%a6) | Save value of p->buf movem.l (3*4,%sp), %d2-%d7/%a2-%a6 lea.l (14*4,%sp), %sp rts