Sorry - you're right with the armlet forum.
I know exactly where the app spends its time - the 2 functions that are of
importance eat about 75% of the time. (Profiled at the desktop, but must be
true - at least roughly - for the HH, too.) Both functions are modified by
the optimization.
I know about the things you write, but I am not able to judge the quality of
the translation, resp. it would take many-many hours until I could collect
some relevant results. (In the past I discovered this way some wrong
"optimizations" done by CW, but it is a painfull proces.) Anyway, I supposed
that the compiler should do that job for me - if not with the best possible
result, then at least with some result.
With best regards
Jan Slodicka
----- Original Message -----
From: "Ron Nicholson" <[EMAIL PROTECTED]>
> Why don't you ask in the PalmOS Armlet forum? The subject might
> already have been discussed there.
> http://www.escribe.com/computing/poaf/index.html
>
> On Thu, 26 Jun 2003 09:51:06, Jan Slodicka writes:
> >I checked it now. I picked up a random function and counted # of asm
> >instructions. It is really so that the optimized code was shorter by some
> >14%. I just wonder why this does not show up in the final product speed.
> >(My experience from the past says that speed optimization always brings
> >measurable improvements.)
>
> Optimization of the wrong thing can make apps slower. If the
> random function you counted did not constitute a large portion
> of where your application spends its time, then the # of instructions
> won't make any measurable difference. You first need to profile
> where your app spends its time. Even if you reduce instruction
> count in the right places, this won't help if the CPU is spending
> most of it's time elsewhere, such as fetching data or instructions
> from memory when your cache hit rate is too low, etc. Some compiler
> optimizations (loop unrolling, etc.) can actually make cache
> thrashing worse. Again, you have to profile your application,
> look at where it spends its time, and what its working set and
> access patterns look like compared to the size of the caches,
> etc. before choosing where and how to optimize.
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