RE: [PATCH] SBC encoder scale factors calculation optimized with __builtin_clz

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The attached patch contains optimization for scale factors calculation

which

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provides additional SBC encoder speedup.

For non-gcc compilers, CLZ function is implemented with a very simple

and

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slow straightforward code (but it is still faster than current git code

even

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if used instead of __builtin_clz). Something better could be done like:
http://groups.google.com/group/comp.sys.arm/msg/5ae56e3a95a2345e?hl=en
But I'm not sure about license/copyright of the code at this link and

decided

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not to touch it. Anyway, I don't think that gcc implementation of
__builtin_clz for the CPU cores which do not support CLZ instruction is

any

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worse.

personally I don't really care about non-gcc compilers. I think that
some of the BlueZ source might not even compile without gcc.

Anyway, patch has been applied. Thanks.

The testing results are not positive. It is better to revoke the patch.
http://net.cs.uni-tuebingen.de/html/nexgenvoip/
http://net.cs.uni-tuebingen.de/html/nexgenvoip/html/encoder.bluez.03.wav


Greetings

 Christian