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/*
libdemac - A Monkey's Audio decoder
$Id$
Copyright (C) Dave Chapman 2007
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"
.section ICODE_SECTION_DEMAC_ARM,"ax",%progbits
.align 2
.global predictor_decode_stereo
.type predictor_decode_stereo,%function
/* 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[] */
@ Macro for loading 2 registers, for various ARM versions.
@ Registers must start with an even register, and must be consecutive.
.macro LDR2OFS reg1, reg2, base, offset
#if ARM_ARCH >= 5
ldrd \reg1, [\base, \offset]
#else /* ARM_ARCH < 5 */
#ifdef CPU_ARM7TDMI
add \reg1, \base, \offset
ldmia \reg1, {\reg1, \reg2}
#else
ldr \reg1, [\base, \offset]
ldr \reg2, [\base, \offset+4]
#endif
#endif /* ARM_ARCH */
.endm
@ Macro for storing 2 registers, for various ARM versions.
@ Registers must start with an even register, and must be consecutive.
.macro STR2OFS reg1, reg2, base, offset
#if ARM_ARCH >= 5
strd \reg1, [\base, \offset]
#else
str \reg1, [\base, \offset]
str \reg2, [\base, \offset+4]
#endif
.endm
@ Register usage:
@
@ r0-r11 - scratch
@ r12 - struct predictor_t* p
@ r14 - int32_t* p->buf
@ void predictor_decode_stereo(struct predictor_t* p,
@ int32_t* decoded0,
@ int32_t* decoded1,
@ int count)
predictor_decode_stereo:
stmdb sp!, {r1-r11, lr}
@ r1 (decoded0) is [sp]
@ r2 (decoded1) is [sp, #4]
@ r3 (count) is [sp, #8]
mov r12, r0 @ r12 := p
ldr r14, [r0] @ r14 := p->buf
loop:
@@@@@@@@@@@@@@@@@@@@@@@@@@@ PREDICTOR Y
@ Predictor Y, Filter A
ldr r11, [r12, #YlastA] @ r11 := p->YlastA
add r2, r14, #YDELAYA-12 @ r2 := &p->buf[YDELAYA-3]
ldmia r2, {r2, r3, r10} @ r2 := p->buf[YDELAYA-3]
@ r3 := p->buf[YDELAYA-2]
@ r10 := p->buf[YDELAYA-1]
add r6, r12, #YcoeffsA
ldmia r6, {r6 - r9} @ r6 := p->YcoeffsA[0]
@ r7 := p->YcoeffsA[1]
@ r8 := p->YcoeffsA[2]
@ r9 := p->YcoeffsA[3]
subs r10, r11, r10 @ r10 := r11 - r10
STR2OFS r10, r11, r14, #YDELAYA-4
@ p->buf[YDELAYA-1] = r10
@ p->buf[YDELAYA] = r11
mul r0, r11, r6 @ r0 := p->buf[YDELAYA] * p->YcoeffsA[0]
mla r0, r10, r7, r0 @ r0 += p->buf[YDELAYA-1] * p->YcoeffsA[1]
mla r0, r3, r8, r0 @ r0 += p->buf[YDELAYA-2] * p->YcoeffsA[2]
mla r0, r2, r9, r0 @ r0 += p->buf[YDELAYA-3] * p->YcoeffsA[3]
@ flags were set above, in the subs instruction
mvngt r10, #0
movlt r10, #1 @ r10 := SIGN(r10) (see .c for SIGN macro)
cmp r11, #0
mvngt r11, #0
movlt r11, #1 @ r11 := SIGN(r11) (see .c for SIGN macro)
STR2OFS r10, r11, r14, #YADAPTCOEFFSA-4
@ p->buf[YADAPTCOEFFSA-1] := r10
@ p->buf[YADAPTCOEFFSA] := r11
@ NOTE: r0 now contains predictionA - don't overwrite.
@ Predictor Y, Filter B
LDR2OFS r6, r7, r12, #YfilterB @ r6 := p->YfilterB
@ r7 := p->XfilterA
add r2, r14, #YDELAYB-16 @ r2 := &p->buf[YDELAYB-4]
ldmia r2, {r2 - r4, r10} @ r2 := p->buf[YDELAYB-4]
@ r3 := p->buf[YDELAYB-3]
@ r4 := p->buf[YDELAYB-2]
@ r10 := p->buf[YDELAYB-1]
rsb r6, r6, r6, lsl #5 @ r6 := r6 * 32 - r6 ( == r6*31)
sub r11, r7, r6, asr #5 @ r11 (p->buf[YDELAYB]) := r7 - (r6 >> 5)
str r7, [r12, #YfilterB] @ p->YfilterB := r7 (p->XfilterA)
add r5, r12, #YcoeffsB
ldmia r5, {r5 - r9} @ r5 := p->YcoeffsB[0]
@ r6 := p->YcoeffsB[1]
@ r7 := p->YcoeffsB[2]
@ r8 := p->YcoeffsB[3]
@ r9 := p->YcoeffsB[4]
subs r10, r11, r10 @ r10 := r11 - r10
STR2OFS r10, r11, r14, #YDELAYB-4
@ p->buf[YDELAYB-1] = r10
@ p->buf[YDELAYB] = r11
mul r1, r11, r5 @ r1 := p->buf[YDELAYB] * p->YcoeffsB[0]
mla r1, r10, r6, r1 @ r1 += p->buf[YDELAYB-1] * p->YcoeffsB[1]
mla r1, r4, r7, r1 @ r1 += p->buf[YDELAYB-2] * p->YcoeffsB[2]
mla r1, r3, r8, r1 @ r1 += p->buf[YDELAYB-3] * p->YcoeffsB[3]
mla r1, r2, r9, r1 @ r1 += p->buf[YDELAYB-4] * p->YcoeffsB[4]
@ flags were set above, in the subs instruction
mvngt r10, #0
movlt r10, #1 @ r10 := SIGN(r10) (see .c for SIGN macro)
cmp r11, #0
mvngt r11, #0
movlt r11, #1 @ r11 := SIGN(r11) (see .c for SIGN macro)
STR2OFS r10, r11, r14, #YADAPTCOEFFSB-4
@ p->buf[YADAPTCOEFFSB-1] := r10
@ p->buf[YADAPTCOEFFSB] := r11
@ r0 still contains predictionA
@ r1 contains predictionB
@ Finish Predictor Y
ldr r2, [sp] @ r2 := decoded0
add r0, r0, r1, asr #1 @ r0 := r0 + (r1 >> 1)
ldr r4, [r12, #YfilterA] @ r4 := p->YfilterA
ldr r3, [r2] @ r3 := *decoded0
rsb r4, r4, r4, lsl #5 @ r4 := r4 * 32 - r4 ( == r4*31)
add r1, r3, r0, asr #10 @ r1 := r3 + (r0 >> 10)
str r1, [r12, #YlastA] @ p->YlastA := r1
add r1, r1, r4, asr #5 @ r1 := r1 + (r4 >> 5)
str r1, [r12, #YfilterA] @ p->YfilterA := r1
@ r1 contains p->YfilterA
@ r2 contains decoded0
@ r3 contains *decoded0
@ r6, r7, r8, r9, r11 contain p->YcoeffsB[0..4]
@ r5, r10 contain p->buf[YADAPTCOEFFSB-1] and p->buf[YADAPTCOEFFSB]
str r1, [r2], #4 @ *(decoded0++) := r1 (p->YfilterA)
str r2, [sp] @ save decoded0
cmp r3, #0
beq 3f
add r2, r14, #YADAPTCOEFFSB-16
ldmia r2, {r2 - r4} @ r2 := p->buf[YADAPTCOEFFSB-4]
@ r3 := p->buf[YADAPTCOEFFSB-3]
@ r4 := p->buf[YADAPTCOEFFSB-2]
blt 1f
@ *decoded0 > 0
sub r5, r5, r11 @ r5 := p->YcoeffsB[0] - p->buf[YADAPTCOEFFSB]
sub r6, r6, r10 @ r6 := p->YcoeffsB[1] - p->buf[YADAPTCOEFFSB-1]
sub r9, r9, r2 @ r9 := p->YcoeffsB[4] - p->buf[YADAPTCOEFFSB-4]
sub r8, r8, r3 @ r8 := p->YcoeffsB[3] - p->buf[YADAPTCOEFFSB-3]
sub r7, r7, r4 @ r7 := p->YcoeffsB[2] - p->buf[YADAPTCOEFFSB-2]
add r0, r12, #YcoeffsB
stmia r0, {r5 - r9} @ Save p->YcoeffsB[]
add r1, r12, #YcoeffsA
ldmia r1, {r2 - r5} @ r2 := p->YcoeffsA[0]
@ r3 := p->YcoeffsA[1]
@ r4 := p->YcoeffsA[2]
@ r5 := p->YcoeffsA[3]
add r6, r14, #YADAPTCOEFFSA-12
ldmia r6, {r6 - r9} @ r6 := p->buf[YADAPTCOEFFSA-3]
@ r7 := p->buf[YADAPTCOEFFSA-2]
@ r8 := p->buf[YADAPTCOEFFSA-1]
@ r9 := p->buf[YADAPTCOEFFSA]
sub r5, r5, r6 @ r5 := p->YcoeffsA[3] - p->buf[YADAPTCOEFFSA-3]
sub r4, r4, r7 @ r4 := p->YcoeffsA[2] - p->buf[YADAPTCOEFFSA-2]
sub r3, r3, r8 @ r3 := p->YcoeffsA[1] - p->buf[YADAPTCOEFFSA-1]
sub r2, r2, r9 @ r2 := p->YcoeffsA[0] - p->buf[YADAPTCOEFFSA]
b 2f
1: @ *decoded0 < 0
add r5, r5, r11 @ r5 := p->YcoeffsB[0] + p->buf[YADAPTCOEFFSB]
add r6, r6, r10 @ r6 := p->YcoeffsB[1] + p->buf[YADAPTCOEFFSB-1]
add r9, r9, r2 @ r9 := p->YcoeffsB[4] + p->buf[YADAPTCOEFFSB-4]
add r8, r8, r3 @ r9 := p->YcoeffsB[3] + p->buf[YADAPTCOEFFSB-3]
add r7, r7, r4 @ r8 := p->YcoeffsB[2] + p->buf[YADAPTCOEFFSB-2]
add r0, r12, #YcoeffsB
stmia r0, {r5 - r9} @ Save p->YcoeffsB[]
add r1, r12, #YcoeffsA
ldmia r1, {r2 - r5} @ r2 := p->YcoeffsA[0]
@ r3 := p->YcoeffsA[1]
@ r4 := p->YcoeffsA[2]
@ r5 := p->YcoeffsA[3]
add r6, r14, #YADAPTCOEFFSA-12
ldmia r6, {r6 - r9} @ r6 := p->buf[YADAPTCOEFFSA-3]
@ r7 := p->buf[YADAPTCOEFFSA-2]
@ r8 := p->buf[YADAPTCOEFFSA-1]
@ r9 := p->buf[YADAPTCOEFFSA]
add r5, r5, r6 @ r5 := p->YcoeffsA[3] + p->buf[YADAPTCOEFFSA-3]
add r4, r4, r7 @ r4 := p->YcoeffsA[2] + p->buf[YADAPTCOEFFSA-2]
add r3, r3, r8 @ r3 := p->YcoeffsA[1] + p->buf[YADAPTCOEFFSA-1]
add r2, r2, r9 @ r2 := p->YcoeffsA[0] + p->buf[YADAPTCOEFFSA]
2:
stmia r1, {r2 - r5} @ Save p->YcoeffsA
3:
@@@@@@@@@@@@@@@@@@@@@@@@@@@ PREDICTOR X
@ Predictor X, Filter A
ldr r11, [r12, #XlastA] @ r11 := p->XlastA
add r2, r14, #XDELAYA-12 @ r2 := &p->buf[XDELAYA-3]
ldmia r2, {r2, r3, r10} @ r2 := p->buf[XDELAYA-3]
@ r3 := p->buf[XDELAYA-2]
@ r10 := p->buf[XDELAYA-1]
add r6, r12, #XcoeffsA
ldmia r6, {r6 - r9} @ r6 := p->XcoeffsA[0]
@ r7 := p->XcoeffsA[1]
@ r8 := p->XcoeffsA[2]
@ r9 := p->XcoeffsA[3]
subs r10, r11, r10 @ r10 := r11 - r10
STR2OFS r10, r11, r14, #XDELAYA-4
@ p->buf[XDELAYA-1] = r10
@ p->buf[XDELAYA] = r11
mul r0, r11, r6 @ r0 := p->buf[XDELAYA] * p->XcoeffsA[0]
mla r0, r10, r7, r0 @ r0 += p->buf[XDELAYA-1] * p->XcoeffsA[1]
mla r0, r3, r8, r0 @ r0 += p->buf[XDELAYA-2] * p->XcoeffsA[2]
mla r0, r2, r9, r0 @ r0 += p->buf[XDELAYA-3] * p->XcoeffsA[3]
@ flags were set above, in the subs instruction
mvngt r10, #0
movlt r10, #1 @ r10 := SIGN(r10) (see .c for SIGN macro)
cmp r11, #0
mvngt r11, #0
movlt r11, #1 @ r11 := SIGN(r11) (see .c for SIGN macro)
STR2OFS r10, r11, r14, #XADAPTCOEFFSA-4
@ p->buf[XADAPTCOEFFSA-1] := r10
@ p->buf[XADAPTCOEFFSA] := r11
@ NOTE: r0 now contains predictionA - don't overwrite.
@ Predictor X, Filter B
LDR2OFS r6, r7, r12, #XfilterB @ r6 := p->XfilterB
@ r7 := p->YfilterA
add r2, r14, #XDELAYB-16 @ r2 := &p->buf[XDELAYB-4]
ldmia r2, {r2 - r4, r10} @ r2 := p->buf[XDELAYB-4]
@ r3 := p->buf[XDELAYB-3]
@ r4 := p->buf[XDELAYB-2]
@ r10 := p->buf[XDELAYB-1]
rsb r6, r6, r6, lsl #5 @ r6 := r2 * 32 - r6 ( == r6*31)
sub r11, r7, r6, asr #5 @ r11 (p->buf[XDELAYB]) := r7 - (r6 >> 5)
str r7, [r12, #XfilterB] @ p->XfilterB := r7 (p->YfilterA)
add r5, r12, #XcoeffsB
ldmia r5, {r5 - r9} @ r5 := p->XcoeffsB[0]
@ r6 := p->XcoeffsB[1]
@ r7 := p->XcoeffsB[2]
@ r8 := p->XcoeffsB[3]
@ r9 := p->XcoeffsB[4]
subs r10, r11, r10 @ r10 := r11 - r10
STR2OFS r10, r11, r14, #XDELAYB-4
@ p->buf[XDELAYB-1] = r10
@ p->buf[XDELAYB] = r11
mul r1, r11, r5 @ r1 := p->buf[XDELAYB] * p->XcoeffsB[0]
mla r1, r10, r6, r1 @ r1 += p->buf[XDELAYB-1] * p->XcoeffsB[1]
mla r1, r4, r7, r1 @ r1 += p->buf[XDELAYB-2] * p->XcoeffsB[2]
mla r1, r3, r8, r1 @ r1 += p->buf[XDELAYB-3] * p->XcoeffsB[3]
mla r1, r2, r9, r1 @ r1 += p->buf[XDELAYB-4] * p->XcoeffsB[4]
@ flags were set above, in the subs instruction
mvngt r10, #0
movlt r10, #1 @ r10 := SIGN(r10) (see .c for SIGN macro)
cmp r11, #0
mvngt r11, #0
movlt r11, #1 @ r11 := SIGN(r11) (see .c for SIGN macro)
STR2OFS r10, r11, r14, #XADAPTCOEFFSB-4
@ p->buf[XADAPTCOEFFSB-1] := r10
@ p->buf[XADAPTCOEFFSB] := r11
@ r0 still contains predictionA
@ r1 contains predictionB
@ Finish Predictor X
ldr r2, [sp, #4] @ r2 := decoded1
add r0, r0, r1, asr #1 @ r0 := r0 + (r1 >> 1)
ldr r4, [r12, #XfilterA] @ r4 := p->XfilterA
ldr r3, [r2] @ r3 := *decoded1
rsb r4, r4, r4, lsl #5 @ r4 := r4 * 32 - r4 ( == r4*31)
add r1, r3, r0, asr #10 @ r1 := r3 + (r0 >> 10)
str r1, [r12, #XlastA] @ p->XlastA := r1
add r1, r1, r4, asr #5 @ r1 := r1 + (r4 >> 5)
str r1, [r12, #XfilterA] @ p->XfilterA := r1
@ r1 contains p->XfilterA
@ r2 contains decoded1
@ r3 contains *decoded1
@ r6, r7, r8, r9, r11 contain p->XcoeffsB[0..4]
@ r5, r10 contain p->buf[XADAPTCOEFFSB-1] and p->buf[XADAPTCOEFFSB]
str r1, [r2], #4 @ *(decoded1++) := r1 (p->XfilterA)
str r2, [sp, #4] @ save decoded1
cmp r3, #0
beq 3f
add r2, r14, #XADAPTCOEFFSB-16
ldmia r2, {r2 - r4} @ r2 := p->buf[XADAPTCOEFFSB-4]
@ r3 := p->buf[XADAPTCOEFFSB-3]
@ r4 := p->buf[XADAPTCOEFFSB-2]
blt 1f
@ *decoded1 > 0
sub r5, r5, r11 @ r5 := p->XcoeffsB[0] - p->buf[XADAPTCOEFFSB]
sub r6, r6, r10 @ r6 := p->XcoeffsB[1] - p->buf[XADAPTCOEFFSB-1]
sub r9, r9, r2 @ r9 := p->XcoeffsB[4] - p->buf[XADAPTCOEFFSB-4]
sub r8, r8, r3 @ r8 := p->XcoeffsB[3] - p->buf[XADAPTCOEFFSB-3]
sub r7, r7, r4 @ r7 := p->XcoeffsB[2] - p->buf[XADAPTCOEFFSB-2]
add r0, r12, #XcoeffsB
stmia r0, {r5 - r9} @ Save p->XcoeffsB[]
add r1, r12, #XcoeffsA
ldmia r1, {r2 - r5} @ r2 := p->XcoeffsA[0]
@ r3 := p->XcoeffsA[1]
@ r4 := p->XcoeffsA[2]
@ r5 := p->XcoeffsA[3]
add r6, r14, #XADAPTCOEFFSA-12
ldmia r6, {r6 - r9} @ r6 := p->buf[XADAPTCOEFFSA-3]
@ r7 := p->buf[XADAPTCOEFFSA-2]
@ r8 := p->buf[XADAPTCOEFFSA-1]
@ r9 := p->buf[XADAPTCOEFFSA]
sub r5, r5, r6 @ r5 := p->XcoeffsA[3] - p->buf[XADAPTCOEFFSA-3]
sub r4, r4, r7 @ r4 := p->XcoeffsA[2] - p->buf[XADAPTCOEFFSA-2]
sub r3, r3, r8 @ r3 := p->XcoeffsA[1] - p->buf[XADAPTCOEFFSA-1]
sub r2, r2, r9 @ r2 := p->XcoeffsA[0] - p->buf[XADAPTCOEFFSA]
b 2f
1: @ *decoded1 < 0
add r5, r5, r11 @ r5 := p->XcoeffsB[0] + p->buf[XADAPTCOEFFSB]
add r6, r6, r10 @ r6 := p->XcoeffsB[1] + p->buf[XADAPTCOEFFSB-1]
add r9, r9, r2 @ r9 := p->XcoeffsB[4] + p->buf[XADAPTCOEFFSB-4]
add r8, r8, r3 @ r8 := p->XcoeffsB[3] + p->buf[XADAPTCOEFFSB-3]
add r7, r7, r4 @ r7 := p->XcoeffsB[2] + p->buf[XADAPTCOEFFSB-2]
add r0, r12, #XcoeffsB
stmia r0, {r5 - r9} @ Save p->XcoeffsB[]
add r1, r12, #XcoeffsA
ldmia r1, {r2 - r5} @ r2 := p->XcoeffsA[0]
@ r3 := p->XcoeffsA[1]
@ r4 := p->XcoeffsA[2]
@ r5 := p->XcoeffsA[3]
add r6, r14, #XADAPTCOEFFSA-12
ldmia r6, {r6 - r9} @ r6 := p->buf[XADAPTCOEFFSA-3]
@ r7 := p->buf[XADAPTCOEFFSA-2]
@ r8 := p->buf[XADAPTCOEFFSA-1]
@ r9 := p->buf[XADAPTCOEFFSA]
add r5, r5, r6 @ r5 := p->XcoeffsA[3] + p->buf[XADAPTCOEFFSA-3]
add r4, r4, r7 @ r4 := p->XcoeffsA[2] + p->buf[XADAPTCOEFFSA-2]
add r3, r3, r8 @ r3 := p->XcoeffsA[1] + p->buf[XADAPTCOEFFSA-1]
add r2, r2, r9 @ r2 := p->XcoeffsA[0] + p->buf[XADAPTCOEFFSA]
2:
stmia r1, {r2 - r5} @ Save p->XcoeffsA
3:
@@@@@@@@@@@@@@@@@@@@@@@@@@@ COMMON
add r14, r14, #4 @ p->buf++
add r11, r12, #historybuffer @ r11 := &p->historybuffer[0]
sub r10, r14, #PREDICTOR_HISTORY_SIZE*4
@ r10 := p->buf - PREDICTOR_HISTORY_SIZE
ldr r0, [sp, #8]
cmp r10, r11
beq move_hist @ The history buffer is full, we need to do a memmove
@ Check loop count
subs r0, r0, #1
strne r0, [sp, #8]
bne loop
done:
str r14, [r12] @ Save value of p->buf
add sp, sp, #12 @ Don't bother restoring r1-r3
ldmia sp!, {r4 - r11, pc}
move_hist:
@ dest = r11 (p->historybuffer)
@ src = r14 (p->buf)
@ n = 200
ldmia r14!, {r0-r9} @ 40 bytes
stmia r11!, {r0-r9}
ldmia r14!, {r0-r9} @ 40 bytes
stmia r11!, {r0-r9}
ldmia r14!, {r0-r9} @ 40 bytes
stmia r11!, {r0-r9}
ldmia r14!, {r0-r9} @ 40 bytes
stmia r11!, {r0-r9}
ldmia r14!, {r0-r9} @ 40 bytes
stmia r11!, {r0-r9}
ldr r0, [sp, #8]
add r14, r12, #historybuffer @ p->buf = &p->historybuffer[0]
@ Check loop count
subs r0, r0, #1
strne r0, [sp, #8]
bne loop
b done
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