Too many cycles in complex multiplication

Dear team,

I am working with the ADSP-SC584 evaluation board and want to analyse the number of cycles of a complex multiplication. I am using CCES 2.12.0.

The number of cycles are 49174 of the complex multiplication. When looking at the assembly code I noticed that the body of the loop needs 11 cycles and the loopcounter is only a 1/4 of the size of my loop.

On another DSP (ADSP-21489) the same code needs a loop with 4 steps and in total only 32786 Cycles. The loopcounter is 1/2 of the size (8191).
I have no idea why the loopcounters the number of cycles in the loop are different. The SHARC architecturesof the DSPs are looking the same for me regarding SIMD performance and bus-architecture.

I have activated the optimization and SIMD in the properties for Core1, so that is not the problem here.

That is a part of the assembly code of the ADSP-21489 and there you can see that the loop only needs 4 cycles do perform the 4 multiplications and the additions are done in the first 2 cycles in parallel. Thats what I was expecting from the SC584 as well.

Why is that not the case for the SC-584? Do I have to enable other properties in my settings or in my code to boost my performance and to lower the cycle number?

Thanks for your advice and help
Philipp

Audio Signal Processors

Audio Products

software

adsp-21489

adsp-sc584

performance

CCES 2.12.0

dsp&processors

SHARC Audio Processors/SoCs

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