Re: [boost] Re: N-Dimensional array library submission...

From: Toon Knapen (toon.knapen_at_[hidden])
Date: 2001-12-26 12:32:12

 What problems were you having with gcc-2.95.3?  I am curious because 
> I developed the library using that as my primary compiler (as well as 
> KAI C++).  

My small 'performance test' for instance (in attach. a fresh copy).

> 
> As for performance testing, I havent done much more than what you did 
> above.  As Beman had mentioned, the "abstraction penalty" of the 
> compiler seems to be a significant issue where performance is 
> concerned.  I have had some great preliminary success with KCC, but 
> more investigation of this is necessary.

Can you elaborate on the performance with KCC ? Does the performance of 
the KCC compiled tests indeed indicate that performance is mostly a 
compiler-problem instead of a C++-abstraction problem.

I just saw multi-array is about to be 'reviewed'. I would suggest that 
for multi-array, as this should be the case for any numerics library in 
boost, performance is also evaluated before and during the review.

Although "early optimisation is the root of all evil", performance 
issues _are_ important for the design of numeric-intensive codes and 
thus also are important for acceptance. On the other hand we don't need 
to be too strict : I think it would be sufficient if there is *at least* 
one multi-platform compiler that can produce efficient code for the 
library, it does not have to super-efficient on all of course. If one 
compiler can generate efficient code, it's a deficiency of the other 
compilers that they are not able to generate good code and not a 
deficiency of the library.