rockbox/apps/dsp_cf.S
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

611 lines
31 KiB
ArmAsm

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Thom Johansen
* Portions Copyright (C) 2007 Michael Sevakis
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/****************************************************************************
* void dsp_apply_gain(int count, struct dsp_data *data, int32_t *buf[])
*/
.section .text
.align 2
.global dsp_apply_gain
dsp_apply_gain:
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l 28(%sp), %a0-%a1 | %a0 = data,
| %a1 = buf
move.l 4(%a0), %d1 | %d1 = data->num_channels
move.l 32(%a0), %a0 | %a0 = data->gain (in s8.23)
10: | channel loop |
move.l 24(%sp), %d0 | %d0 = count
move.l -4(%a1, %d1.l*4), %a2 | %a2 = s = buf[ch-1]
move.l %a2, %a3 | %a3 = d = s
move.l (%a2)+, %d2 | %d2 = *s++,
mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1)
subq.l #1, %d0 | --count > 0 ? : effectively n++
ble.b 30f | loop done | no? finish up
20: | loop |
move.l %accext01, %d4 | fetch S(n-1)[7:0]
movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0]
asl.l #8, %d3 | *s++ = (S(n-1)[40:8] << 8) | S(n-1)[7:0]
mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1)
move.b %d4, %d3 |
move.l %d3, (%a3)+ |
subq.l #1, %d0 | --count > 0 ? : effectively n++
bgt.b 20b | loop | yes? do more samples
30: | loop done |
move.l %accext01, %d4 | fetch S(n-1)[7:0]
movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0]
asl.l #8, %d3 | *s = (S(n-1)[40:8] << 8) | S(n-1)[7:0]
move.b %d4, %d3 |
move.l %d3, (%a3) |
subq.l #1, %d1 | next channel
bgt.b 10b | channel loop |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup stack
rts |
.size dsp_apply_gain,.-dsp_apply_gain
/****************************************************************************
* void apply_crossfeed(int count, int32_t *buf[])
*/
.section .text
.align 2
.global apply_crossfeed
apply_crossfeed:
lea.l -44(%sp), %sp |
movem.l %d2-%d7/%a2-%a6, (%sp) | save all regs
movem.l 48(%sp), %d7/%a4 | %d7 = count, %a4 = src
movem.l (%a4), %a4-%a5 | %a4 = src[0], %a5 = src[1]
lea.l crossfeed_data, %a1 | %a1 = &crossfeed_data
move.l (%a1)+, %d6 | %d6 = direct gain
movem.l 12(%a1), %d0-%d3 | fetch filter history samples
move.l 132(%a1), %a0 | fetch delay line address
movem.l (%a1), %a1-%a3 | load filter coefs
lea.l crossfeed_data+136, %a6 | %a6 = delay line wrap limit
bra.b 20f | loop start | go to loop start point
/* Register usage in loop:
* %a0 = delay_p, %a1..%a3 = b0, b1, a1 (filter coefs),
* %a4 = buf[0], %a5 = buf[1],
* %a6 = delay line pointer wrap limit,
* %d0..%d3 = history
* %d4..%d5 = temp.
* %d6 = direct gain,
* %d7 = count
*/
10: | loop |
movclr.l %acc0, %d4 | write outputs
move.l %d4, (%a4)+ | .
movclr.l %acc1, %d5 | .
move.l %d5, (%a5)+ | .
20: | loop start |
mac.l %a2, %d0, (%a0)+, %d0, %acc0 | %acc0 = b1*dl[n - 1], %d0 = dl[n]
mac.l %a1, %d0 , %acc0 | %acc0 += b0*dl[n]
mac.l %a3, %d1, (%a5), %d5, %acc0 | %acc0 += a1*y_r[n - 1], load R
mac.l %a2, %d2, (%a0)+, %d2, %acc1 | %acc1 = b1*dr[n - 1], %d2 = dr[n]
mac.l %a1, %d2 , %acc1 | %acc1 += b0*dr[n]
mac.l %a3, %d3, (%a4), %d4, %acc1 | %acc1 += a1*y_l[n - 1], load L
movem.l %d4-%d5, -8(%a0) | save left & right inputs to delay line
move.l %acc0, %d3 | get filtered delayed left sample (y_l[n])
move.l %acc1, %d1 | get filtered delayed right sample (y_r[n])
mac.l %d6, %d4, %acc0 | %acc0 += gain*x_l[n]
mac.l %d6, %d5, %acc1 | %acc1 += gain*x_r[n]
cmp.l %a6, %a0 | wrap %a0 if passed end
bhs.b 30f | wrap buffer |
.word 0x51fb | tpf.l | trap the buffer wrap
30: | wrap buffer | ...fwd taken branches more costly
lea.l -104(%a0), %a0 | wrap it up
subq.l #1, %d7 | --count > 0 ?
bgt.b 10b | loop | yes? do more
movclr.l %acc0, %d4 | write last outputs
move.l %d4, (%a4) | .
movclr.l %acc1, %d5 | .
move.l %d5, (%a5) | .
lea.l crossfeed_data+16, %a1 | save data back to struct
movem.l %d0-%d3, (%a1) | ...history
move.l %a0, 120(%a1) | ...delay_p
movem.l (%sp), %d2-%d7/%a2-%a6 | restore all regs
lea.l 44(%sp), %sp |
rts |
.size apply_crossfeed,.-apply_crossfeed
/****************************************************************************
* int dsp_downsample(int count, struct dsp_data *data,
* in32_t *src[], int32_t *dst[])
*/
.section .text
.align 2
.global dsp_downsample
dsp_downsample:
lea.l -40(%sp), %sp | save non-clobberables
movem.l %d2-%d7/%a2-%a5, (%sp) |
movem.l 44(%sp), %d2/%a0-%a2 | %d2 = count
| %a0 = data
| %a1 = src
| %a2 = dst
movem.l 4(%a0), %d3-%d4 | %d3 = ch = data->num_channels
| %d4 = delta = data->resample_data.delta
moveq.l #16, %d7 | %d7 = shift
10: | channel loop |
move.l 12(%a0), %d5 | %d5 = phase = data->resample_data.phase
move.l -4(%a1, %d3.l*4), %a3 | %a3 = s = src[ch-1]
move.l -4(%a2, %d3.l*4), %a4 | %a4 = d = dst[ch-1]
lea.l 12(%a0, %d3.l*4), %a5 | %a5 = &data->resample_data.ast_sample[ch-1]
move.l (%a5), %d0 | %d0 = last = data->resample_data.last_sample[ch-1]
move.l -4(%a3, %d2.l*4), (%a5) | data->resample_data.last_sample[ch-1] = s[count-1]
move.l %d5, %d6 | %d6 = pos = phase >> 16
lsr.l %d7, %d6 |
cmp.l %d2, %d6 | past end of samples?
bge.b 40f | skip resample loop| yes? skip loop
tst.l %d6 | need last sample of prev. frame?
bne.b 20f | resample loop | no? start main loop
move.l (%a3, %d6.l*4), %d1 | %d1 = s[pos]
bra.b 30f | resample start last | start with last (last in %d0)
20: | resample loop |
lea.l -4(%a3, %d6.l*4), %a5 | load s[pos-1] and s[pos]
movem.l (%a5), %d0-%d1 |
30: | resample start last |
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
move.l %d0, %acc0 | %acc0 = previous sample
move.l %d5, %d0 | frac = (phase << 16) >> 1
lsl.l %d7, %d0 |
lsr.l #1, %d0 |
mac.l %d0, %d1, %acc0 | %acc0 += frac * diff
add.l %d4, %d5 | phase += delta
move.l %d5, %d6 | pos = phase >> 16
lsr.l %d7, %d6 |
movclr.l %acc0, %d0 |
move.l %d0, (%a4)+ | *d++ = %d0
cmp.l %d2, %d6 | pos < count?
blt.b 20b | resample loop | yes? continue resampling
40: | skip resample loop |
subq.l #1, %d3 | ch > 0?
bgt.b 10b | channel loop | yes? process next channel
lsl.l %d7, %d2 | wrap phase to start of next frame
sub.l %d2, %d5 | data->resample_data.phase =
move.l %d5, 12(%a0) | ... phase - (count << 16)
move.l %a4, %d0 | return d - d[0]
sub.l (%a2), %d0 |
asr.l #2, %d0 | convert bytes->samples
movem.l (%sp), %d2-%d7/%a2-%a5 | restore non-clobberables
lea.l 40(%sp), %sp | cleanup stack
rts | buh-bye
.size dsp_downsample,.-dsp_downsample
/****************************************************************************
* int dsp_upsample(int count, struct dsp_data *dsp,
* int32_t *src[], int32_t *dst[])
*/
.section .text
.align 2
.global dsp_upsample
dsp_upsample:
lea.l -40(%sp), %sp | save non-clobberables
movem.l %d2-%d7/%a2-%a5, (%sp) |
movem.l 44(%sp), %d2/%a0-%a2 | %d2 = count
| %a0 = data
| %a1 = src
| %a2 = dst
movem.l 4(%a0), %d3-%d4 | %d3 = ch = channels
| %d4 = delta = data->resample_data.delta
swap %d4 | swap delta to high word to use...
| ...carries to increment position
10: | channel loop |
move.l 12(%a0), %d5 | %d5 = phase = data->resample_data.phase
move.l -4(%a1, %d3.l*4), %a3 | %a3 = s = src[ch-1]
lea.l 12(%a0, %d3.l*4), %a4 | %a4 = &data->resample_data.last_sample[ch-1]
lea.l -4(%a3, %d2.l*4), %a5 | %a5 = src_end = &src[count-1]
move.l (%a4), %d0 | %d0 = last = data->resample_data.last_sample[ch-1]
move.l (%a5), (%a4) | data->resample_data.last_sample[ch-1] = s[count-1]
move.l -4(%a2, %d3.l*4), %a4 | %a4 = d = dst[ch-1]
move.l (%a3)+, %d1 | fetch first sample - might throw this...
| ...away later but we'll be preincremented
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[0] - last
swap %d5 | swap phase to high word to use
| carries to increment position
move.l %d5, %d7 | %d7 = pos = phase >> 16
clr.w %d5 |
eor.l %d5, %d7 | pos == 0?
beq.b 40f | loop start | yes? start loop
cmp.l %d2, %d7 | past end of samples?
bge.b 50f | skip resample loop| yes? go to next channel and collect info
lea.l (%a3, %d7.l*4), %a3 | %a3 = s = &s[pos+1]
movem.l -8(%a3), %d0-%d1 | %d0 = s[pos-1], %d1 = s[pos]
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
bra.b 40f | loop start |
20: | next sample loop |
move.l %d6, %d0 | move previous sample to %d0
move.l (%a3)+, %d1 | fetch next sample
move.l %d1, %d6 | save sample value
sub.l %d0, %d1 | %d1 = diff = s[pos] - s[pos-1]
30: | same sample loop |
movclr.l %acc0, %d7 | %d7 = result
move.l %d7, (%a4)+ | *d++ = %d7
40: | loop start |
lsr.l #1, %d5 | make phase into frac
move.l %d0, %acc0 | %acc0 = s[pos-1]
mac.l %d1, %d5, %acc0 | %acc0 = diff * frac
lsl.l #1, %d5 | restore frac to phase
add.l %d4, %d5 | phase += delta
bcc.b 30b | same sample loop | load next values?
cmp.l %a5, %a3 | src <= src_end?
bls.b 20b | next sample loop | yes? continue resampling
movclr.l %acc0, %d7 | %d7 = result
move.l %d7, (%a4)+ | *d++ = %d7
50: | skip resample loop |
subq.l #1, %d3 | ch > 0?
bgt.b 10b | channel loop | yes? process next channel
swap %d5 | wrap phase to start of next frame
move.l %d5, 12(%a0) | ...and save in data->resample_data.phase
move.l %a4, %d0 | return d - d[0]
sub.l (%a2), %d0 |
movem.l (%sp), %d2-%d7/%a2-%a5 | restore non-clobberables
asr.l #2, %d0 | convert bytes->samples
lea.l 40(%sp), %sp | cleanup stack
rts | buh-bye
.size dsp_upsample,.-dsp_upsample
/****************************************************************************
* void channels_process_sound_chan_mono(int count, int32_t *buf[])
*
* Mix left and right channels 50/50 into a center channel.
*/
.section .text
.align 2
.global channels_process_sound_chan_mono
channels_process_sound_chan_mono:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l #0x40000000, %d3 | %d3 = 0.5
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc0 |
subq.l #1, %d0 |
ble.s 20f | loop done |
10: | loop |
movclr.l %acc0, %d4 | L = R = l/2 + r/2
mac.l %d1, %d3, (%a0)+, %d1, %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc0 |
move.l %d4, (%a2)+ | output to original buffer
move.l %d4, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d4 | output last sample
move.l %d4, (%a2) |
move.l %d4, (%a3) |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_mono, \
.-channels_process_sound_chan_mono
/****************************************************************************
* void channels_process_sound_chan_custom(int count, int32_t *buf[])
*
* Apply stereo width (narrowing/expanding) effect.
*/
.section .text
.align 2
.global channels_process_sound_chan_custom
channels_process_sound_chan_custom:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -28(%sp), %sp | save registers
movem.l %d2-%d6/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l dsp_sw_gain, %d3 | load straight (mid) gain
move.l dsp_sw_cross, %d4 | load cross (side) gain
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross
mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross
mac.l %d2, %d4 , %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc1 |
subq.l #1, %d0 |
ble.b 20f | loop done |
10: | loop |
movclr.l %acc0, %d5 |
movclr.l %acc1, %d6 |
mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross
mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross
mac.l %d2, %d4 , %acc0 |
mac.l %d2, %d3, (%a1)+, %d2, %acc1 |
move.l %d5, (%a2)+ |
move.l %d6, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d5 | output last sample
movclr.l %acc1, %d6 |
move.l %d5, (%a2) |
move.l %d6, (%a3) |
movem.l (%sp), %d2-%d6/%a2-%a3 | restore registers
lea.l 28(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_custom, \
.-channels_process_sound_chan_custom
/****************************************************************************
* void channels_process_sound_chan_karaoke(int count, int32_t *buf[])
*
* Separate channels into side channels.
*/
.section .text
.align 2
.global channels_process_sound_chan_karaoke
channels_process_sound_chan_karaoke:
movem.l 4(%sp), %d0/%a0 | %d0 = count, %a0 = buf
lea.l -20(%sp), %sp | save registers
movem.l %d2-%d4/%a2-%a3, (%sp) |
movem.l (%a0), %a0-%a1 | get channel src pointers
move.l %a0, %a2 | use separate dst pointers since read
move.l %a1, %a3 | pointers run one ahead of write
move.l #0x40000000, %d3 | %d3 = 0.5
move.l (%a0)+, %d1 | prime the input registers
move.l (%a1)+, %d2 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2
msac.l %d2, %d3, (%a1)+, %d2, %acc0 |
subq.l #1, %d0 |
ble.b 20f | loop done |
10: | loop |
movclr.l %acc0, %d4 |
mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2
msac.l %d2, %d3, (%a1)+, %d2, %acc0 |
move.l %d4, (%a2)+ |
neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2
move.l %d4, (%a3)+ |
subq.l #1, %d0 |
bgt.s 10b | loop |
20: | loop done |
movclr.l %acc0, %d4 | output last sample
move.l %d4, (%a2) |
neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2
move.l %d4, (%a3) |
movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers
lea.l 20(%sp), %sp | cleanup
rts |
.size channels_process_sound_chan_karaoke, \
.-channels_process_sound_chan_karaoke
/****************************************************************************
* void sample_output_stereo(int count, struct dsp_data *data,
* int32_t *src[], int16_t *dst)
*
* Framework based on the ubiquitous Rockbox line transfer logic for
* Coldfire CPUs.
*
* Does emac clamping and scaling (which proved faster than the usual
* checks and branches - even single test clamping) and writes using
* line burst transfers. Also better than writing a single L-R pair per
* loop but a good deal more code.
*
* Attemping bursting during reads is rather futile since the source and
* destination alignments rarely agree and too much complication will
* slow us up. The parallel loads seem to do a bit better at least until
* a pcm buffer can always give line aligned chunk and then aligning the
* dest can then imply the source is aligned if the source buffers are.
* For now longword alignment is assumed of both the source and dest.
*
*/
.section .text
.align 2
.global sample_output_stereo
sample_output_stereo:
lea.l -48(%sp), %sp | save registers
move.l %macsr, %d1 | do it now as at many lines will
movem.l %d1-%d7/%a2-%a6, (%sp) | be the far more common condition
move.l #0x80, %macsr | put emac unit in signed int mode
movem.l 52(%sp), %a0-%a2/%a4 |
lea.l (%a4, %a0.l*4), %a0 | %a0 = end address
move.l (%a1), %d1 | %a1 = multiplier: (1 << (16 - scale))
sub.l #16, %d1 |
neg.l %d1 |
moveq.l #1, %d0 |
asl.l %d1, %d0 |
move.l %d0, %a1 |
move.l #0x8000, %a6 | %a6 = rounding term
movem.l (%a2), %a2-%a3 | get L/R channel pointers
moveq.l #28, %d0 | %d0 = second line bound
add.l %a4, %d0 |
and.l #0xfffffff0, %d0 |
cmp.l %a0, %d0 | at least a full line?
bhi.w 40f | long loop 1 start | no? do as trailing longwords
sub.l #16, %d0 | %d1 = first line bound
cmp.l %a4, %d0 | any leading longwords?
bls.b 20f | line loop start | no? start line loop
10: | long loop 0 |
move.l (%a2)+, %d1 | read longword from L and R
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
mac.l %d1, %a1, (%a3)+, %d2, %acc0 | shift L to high word
mac.l %d2, %a1, %acc1 | shift R to high word
movclr.l %acc0, %d1 | get possibly saturated results
movclr.l %acc1, %d2 |
swap %d2 | move R to low word
move.w %d2, %d1 | interleave MS 16 bits of each
move.l %d1, (%a4)+ | ...and write both
cmp.l %a4, %d0 |
bhi.b 10b | long loop 0 |
20: | line loop start |
lea.l -12(%a0), %a5 | %a5 = at or just before last line bound
30: | line loop |
move.l (%a3)+, %d4 | get next 4 R samples and scale
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d4, %a1, (%a3)+, %d5, %acc0 | with saturation
mac.l %d5, %a1, (%a3)+, %d6, %acc1 |
mac.l %d6, %a1, (%a3)+, %d7, %acc2 |
mac.l %d7, %a1, (%a2)+, %d0, %acc3 |
lea.l 16(%a4), %a4 | increment dest here, mitigate stalls
movclr.l %acc0, %d4 | obtain R results
movclr.l %acc1, %d5 |
movclr.l %acc2, %d6 |
movclr.l %acc3, %d7 |
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d0, %a1, (%a2)+, %d1, %acc0 | get next 4 L samples and scale
mac.l %d1, %a1, (%a2)+, %d2, %acc1 | with saturation
mac.l %d2, %a1, (%a2)+, %d3, %acc2 |
mac.l %d3, %a1 , %acc3 |
swap %d4 | a) interleave most significant...
swap %d5 |
swap %d6 |
swap %d7 |
movclr.l %acc0, %d0 | obtain L results
movclr.l %acc1, %d1 |
movclr.l %acc2, %d2 |
movclr.l %acc3, %d3 |
move.w %d4, %d0 | a) ... 16 bits of L and R
move.w %d5, %d1 |
move.w %d6, %d2 |
move.w %d7, %d3 |
movem.l %d0-%d3, -16(%a4) | write four stereo samples
cmp.l %a4, %a5 |
bhi.b 30b | line loop |
40: | long loop 1 start |
cmp.l %a4, %a0 | any longwords left?
bls.b 60f | output end | no? stop
50: | long loop 1 |
move.l (%a2)+, %d1 | handle trailing longwords
move.l %a6, %acc0 |
move.l %acc0, %acc1 |
mac.l %d1, %a1, (%a3)+, %d2, %acc0 | the same way as leading ones
mac.l %d2, %a1, %acc1 |
movclr.l %acc0, %d1 |
movclr.l %acc1, %d2 |
swap %d2 |
move.w %d2, %d1 |
move.l %d1, (%a4)+ |
cmp.l %a4, %a0 |
bhi.b 50b | long loop 1
60: | output end |
movem.l (%sp), %d1-%d7/%a2-%a6 | restore registers
move.l %d1, %macsr |
lea.l 48(%sp), %sp | cleanup
rts |
.size sample_output_stereo, .-sample_output_stereo
/****************************************************************************
* void sample_output_mono(int count, struct dsp_data *data,
* int32_t *src[], int16_t *dst)
*
* Same treatment as sample_output_stereo but for one channel.
*/
.section .text
.align 2
.global sample_output_mono
sample_output_mono:
lea.l -32(%sp), %sp | save registers
move.l %macsr, %d1 | do it now as at many lines will
movem.l %d1-%d5/%a2-%a4, (%sp) | be the far more common condition
move.l #0x80, %macsr | put emac unit in signed int mode
movem.l 36(%sp), %a0-%a3 |
lea.l (%a3, %a0.l*4), %a0 | %a0 = end address
move.l (%a1), %d1 | %d5 = multiplier: (1 << (16 - scale))
sub.l #16, %d1 |
neg.l %d1 |
moveq.l #1, %d5 |
asl.l %d1, %d5 |
move.l #0x8000, %a4 | %a4 = rounding term
movem.l (%a2), %a2 | get source channel pointer
moveq.l #28, %d0 | %d0 = second line bound
add.l %a3, %d0 |
and.l #0xfffffff0, %d0 |
cmp.l %a0, %d0 | at least a full line?
bhi.w 40f | long loop 1 start | no? do as trailing longwords
sub.l #16, %d0 | %d1 = first line bound
cmp.l %a3, %d0 | any leading longwords?
bls.b 20f | line loop start | no? start line loop
10: | long loop 0 |
move.l (%a2)+, %d1 | read longword from L and R
move.l %a4, %acc0 |
mac.l %d1, %d5, %acc0 | shift L to high word
movclr.l %acc0, %d1 | get possibly saturated results
move.l %d1, %d2 |
swap %d2 | move R to low word
move.w %d2, %d1 | duplicate single channel into
move.l %d1, (%a3)+ | L and R
cmp.l %a3, %d0 |
bhi.b 10b | long loop 0 |
20: | line loop start |
lea.l -12(%a0), %a1 | %a1 = at or just before last line bound
30: | line loop |
move.l (%a2)+, %d0 | get next 4 L samples and scale
move.l %a4, %acc0 |
move.l %acc0, %acc1 |
move.l %acc1, %acc2 |
move.l %acc2, %acc3 |
mac.l %d0, %d5, (%a2)+, %d1, %acc0 | with saturation
mac.l %d1, %d5, (%a2)+, %d2, %acc1 |
mac.l %d2, %d5, (%a2)+, %d3, %acc2 |
mac.l %d3, %d5 , %acc3 |
lea.l 16(%a3), %a3 | increment dest here, mitigate stalls
movclr.l %acc0, %d0 | obtain results
movclr.l %acc1, %d1 |
movclr.l %acc2, %d2 |
movclr.l %acc3, %d3 |
move.l %d0, %d4 | duplicate single channel
swap %d4 | into L and R
move.w %d4, %d0 |
move.l %d1, %d4 |
swap %d4 |
move.w %d4, %d1 |
move.l %d2, %d4 |
swap %d4 |
move.w %d4, %d2 |
move.l %d3, %d4 |
swap %d4 |
move.w %d4, %d3 |
movem.l %d0-%d3, -16(%a3) | write four stereo samples
cmp.l %a3, %a1 |
bhi.b 30b | line loop |
40: | long loop 1 start |
cmp.l %a3, %a0 | any longwords left?
bls.b 60f | output end | no? stop
50: | loop loop 1 |
move.l (%a2)+, %d1 | handle trailing longwords
move.l %a4, %acc0 |
mac.l %d1, %d5, %acc0 | the same way as leading ones
movclr.l %acc0, %d1 |
move.l %d1, %d2 |
swap %d2 |
move.w %d2, %d1 |
move.l %d1, (%a3)+ |
cmp.l %a3, %a0 |
bhi.b 50b | long loop 1 |
60: | output end |
movem.l (%sp), %d1-%d5/%a2-%a4 | restore registers
move.l %d1, %macsr |
lea.l 32(%sp), %sp | cleanup
rts |
.size sample_output_mono, .-sample_output_mono