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ARM DSP: Add assembly custom sound channel processing. 13% to 14% faster than currently-used default C code on ARMv4.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25949 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Michael Sevakis 2010-05-11 12:37:49 +00:00
parent 68da06f3dc
commit 565a863dd5
2 changed files with 77 additions and 9 deletions
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85
apps/dsp_arm.S
View file

@ -22,10 +22,6 @@
/****************************************************************************
* void channels_process_sound_chan_mono(int count, int32_t *buf[])
*
* NOTE: The following code processes two samples at once. When count is odd,
* there is an additional obsolete sample processed, which will not be
* used by the calling functions.
*/
.section .icode, "ax", %progbits
.align 2
@ -63,13 +59,84 @@ channels_process_sound_chan_mono:
@
ldmfd sp!, { r4, pc } @
.size channels_process_sound_chan_mono, \
.-channels_process_sound_chan_mono
.-channels_process_sound_chan_mono
/****************************************************************************
* void channels_process_sound_chan_custom(int count, int32_t *buf[])
*/
.section .icode, "ax", %progbits
.align 2
.global channels_process_sound_chan_custom
.type channels_process_sound_chan_custom, %function
channels_process_sound_chan_custom:
stmfd sp!, { r4-r10, lr }
ldr r3, =dsp_sw_gain
ldr r4, =dsp_sw_cross
ldmia r1, { r1, r2 } @ r1 = buf[0], r2 = buf[1]
ldr r3, [r3] @ r3 = dsp_sw_gain
ldr r4, [r4] @ r4 = dsp_sw_cross
subs r0, r0, #1
beq .custom_single_sample @ Zero? Only one sample!
.custom_loop:
ldmia r1, { r5, r6 } @ r5 = Li0, r6 = Li1
ldmia r2, { r7, r8 } @ r7 = Ri0, r8 = Ri1
subs r0, r0, #2
smull r9, r10, r5, r3 @ Lc0 = Li0*gain
smull r12, r14, r7, r3 @ Rc0 = Ri0*gain
smlal r9, r10, r7, r4 @ Lc0 += Ri0*cross
smlal r12, r14, r5, r4 @ Rc0 += Li0*cross
mov r9, r9, lsr #31 @ Convert to s0.31
mov r12, r12, lsr #31
orr r5, r9, r10, asl #1
orr r7, r12, r14, asl #1
smull r9, r10, r6, r3 @ Lc1 = Li1*gain
smull r12, r14, r8, r3 @ Rc1 = Ri1*gain
smlal r9, r10, r8, r4 @ Lc1 += Ri1*cross
smlal r12, r14, r6, r4 @ Rc1 += Li1*cross
mov r9, r9, lsr #31 @ Convert to s0.31
mov r12, r12, lsr #31
orr r6, r9, r10, asl #1
orr r8, r12, r14, asl #1
stmia r1!, { r5, r6 } @ Store Lc0, Lc1
stmia r2!, { r7, r8 } @ Store Rc0, Rc1
bgt .custom_loop
ldmltfd sp!, { r4-r10, pc } @ < 0? even count
.custom_single_sample:
ldr r5, [r1] @ handle odd sample
ldr r7, [r2]
smull r9, r10, r5, r3 @ Lc0 = Li0*gain
smull r12, r14, r7, r3 @ Rc0 = Ri0*gain
smlal r9, r10, r7, r4 @ Lc0 += Ri0*cross
smlal r12, r14, r5, r4 @ Rc0 += Li0*cross
mov r9, r9, lsr #31 @ Convert to s0.31
mov r12, r12, lsr #31
orr r5, r9, r10, asl #1
orr r7, r12, r14, asl #1
str r5, [r1] @ Store Lc0
str r7, [r2] @ Store Rc0
ldmfd sp!, { r4-r10, pc }
.size channels_process_sound_chan_custom, \
.-channels_process_sound_chan_custom
/****************************************************************************
* void channels_process_sound_chan_karaoke(int count, int32_t *buf[])
* NOTE: The following code processes two samples at once. When count is odd,
* there is an additional obsolete sample processed, which will not be
* used by the calling functions.
*/
.section .icode, "ax", %progbits
.align 2

1
apps/dsp_asm.h
View file

@ -30,6 +30,7 @@
#define DSP_HAVE_ASM_RESAMPLING
#define DSP_HAVE_ASM_CROSSFEED
#define DSP_HAVE_ASM_SOUND_CHAN_MONO
#define DSP_HAVE_ASM_SOUND_CHAN_CUSTOM
#define DSP_HAVE_ASM_SOUND_CHAN_KARAOKE
#define DSP_HAVE_ASM_SAMPLE_OUTPUT_MONO
#define DSP_HAVE_ASM_SAMPLE_OUTPUT_STEREO