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Re: gcc loop unrolling problem ??

From: Matt Fago <fago at caltech dot edu>
To: Jan Hubicka <hubicka at ucw dot cz>
Cc: gcc at gcc dot gnu dot org
Date: Thu, 12 Feb 2004 07:28:04 -0800
Subject: Re: gcc loop unrolling problem ??

The number of unrollings depends on size of the loop and is bound to 8
maximally.  Your loop has only single instruction so you get maximal
unrolling.  See documentation of --param max-unrolled-insns,
max-unroll-times and friends.

Is this also the case for loops with a constant number of iterations (my loops tend to be in powers of 3)? Should the documentation mention that the default value for max-unroll-times=8?


Thanks,
Matt

Follow-Ups:
- Re: gcc loop unrolling problem ??
  - From: Robert Dewar

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