Loop unrolling

[Scott A Crosby]

On Wed, 3 Jun 1998, Nathan Myers wrote:

> This is absolutely correct.  The performance of programs that use STL
> facilities, and similar libraries like Blitz++, is utterly dependent on 
> the compiler crushing out "abstraction overhead", which often means 
> empty loops.  
> 
> It is impossible in general for the programmer to ensure that empty loops 
> are not generated, because with templates there is no one place in the source
> where all such knowledge is available.
> 
> Perhaps in C code such loops cannot be eliminated without some political
> wrangling, but there can be no such excuse for g++. 

I hate to bring up a 3 month-old horse, but has anyone added in such
functionality to remove empty loops, unconditionally? (Or, could a
complete newbie GCC/EGCS hacker add it in himself and submit a patch?)

Scott


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