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bit_rev is too slow when fft

Started by Xuchen Yao August 15, 2007
Hi,

Using C67x DSP library, whenever we perform FFT, like DSPF_sp_cfftr2_dit()
or DSPF_sp_icfftr2_dif(), we must use bit_rev(). But bit_rev() is not in the
DSP library, what I get is only C code written in "TMS320C67x DSP Library
Programmer's Reference Guide". After some profiling, I found it extremely
slow. Do we have ASM code for this function? Thank you.

Xuchen
See DSPF_sp_bitrev_cplx()

--- Xuchen Yao wrote:

> Hi,
>
> Using C67x DSP library, whenever we perform FFT,
> like DSPF_sp_cfftr2_dit()
> or DSPF_sp_icfftr2_dif(), we must use bit_rev(). But
> bit_rev() is not in the
> DSP library, what I get is only C code written in
> "TMS320C67x DSP Library
> Programmer's Reference Guide". After some profiling,
> I found it extremely
> slow. Do we have ASM code for this function? Thank
> you.
>
> Xuchen

____________________________________________________________________________________
Park yourself in front of a world of choices in alternative vehicles. Visit the Yahoo! Auto Green Center.
http://autos.yahoo.com/green_center/
Yes, that works! Thank you very much.

Xuchen

________________________________________
From: c... [mailto:c...] On Behalf Of Andrew
Elder
Sent: Thursday, August 16, 2007 12:12 AM
To: Xuchen Yao; c...
Subject: Re: [c6x] bit_rev is too slow when fft
See DSPF_sp_bitrev_cplx()

--- Xuchen Yao wrote:

> Hi,
>
> Using C67x DSP library, whenever we perform FFT,
> like DSPF_sp_cfftr2_dit()
> or DSPF_sp_icfftr2_dif(), we must use bit_rev(). But
> bit_rev() is not in the
> DSP library, what I get is only C code written in
> "TMS320C67x DSP Library
> Programmer's Reference Guide". After some profiling,
> I found it extremely
> slow. Do we have ASM code for this function? Thank
> you.
>
> Xuchen

__________________________________________________________
Park yourself in front of a world of choices in alternative vehicles. Visit
the Yahoo! Auto Green Center.
http://autos.yahoo.com/green_center/