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Re: Loop unrolling
- Subject: Re: Loop unrolling
- From: Scott A Crosby <crosby at qwes dot math dot cmu dot edu>
- Date: Wed, 16 Sep 1998 02:28:31 -0400 (EDT)
- cc: egcs at cygnus dot com
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?)
This message is copyright 1998 by Scott A Crosby. Unauthorized
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