[tremor] ARM ASM performance gains, EVC vs. GCC

[Nicolas Pitre]

On Fri, 4 Oct 2002, marc dukette wrote:

> I have also been looking at replacing Nicholas' original port with Tremor in
> the PocketDivx project, which uses EVC as well.  While I cannot compare the
> performance between tremor compiled with eVC vs GCC I can tell you that some
> of the optimizations made for GCC with tremor have had the reverse effect
> under EVC and that currently when compiled with EVC Tremor does not perform
> nearly as well as Nicholas' original port.  

This is interesting to say the least.  Current Tremor from CVS shouldn't be 
worse than my original port (which isn't fully compliant with the Vorbis 
spec btw).

At least, if you replace "#ifdef __i386__" with "#if 1" in misc.h then the 
generated code should be about the same as with my old version for the most 
CPU intensive part.

Is there anyone able to convince EVC to produce assembly output with mdct.c?  
I'd be interested to see that.

<p>Nicolas

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