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Re: recog.c apply_change_group ret zero if num_changes is 0.
- From: Jan Hubicka <jh at suse dot cz>
- To: Joern Rennecke <joern dot rennecke at superh dot com>
- Cc: Graham Stott <graham dot stott at btinternet dot com>, gcc at gcc dot gnu dot org
- Date: Mon, 15 Jul 2002 16:48:57 +0200
- Subject: Re: recog.c apply_change_group ret zero if num_changes is 0.
- References: <3D32AC38.A53585A6@superh.com>
> > * recog.c (apply_change_group): Return zero if no changes.
>
> Don't do that. That is not only in contradiction to the
> function's description, it'll break a lot of optimizations
> too, ones that test if a - possibly empty - set of required
> changes works before installing another change.
As an alternative it may make sense to make number of changes available
to the caller. For instance GCSE pass did contain code that sometimes
makes no changes, but believe it did and causes re-iteration of
algorithm.
Honza
>
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