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Re: Combine misses commutativity
- From: "Paulo J. Matos" <paulo at matos-sorge dot com>
- To: gcc at gcc dot gnu dot org
- Date: Fri, 10 Feb 2012 17:25:23 +0000 (UTC)
- Subject: Re: Combine misses commutativity
- References: <jh3iab$53r$1@dough.gmane.org>
On Fri, 10 Feb 2012 16:57:48 +0000, Paulo J. Matos wrote:
> However, duplicating the instructions and inverting operand order seems
> to defeat the purpose of '%'. So, what's the catch? Or is it a genuine
> bug?
I just understood my miss understanding above. '%' is part of constraints
which as far as I know is only taken into account by the ira/reload
stuff, etc. Combine doesn't look at it and therefore misses this
information.
Now, is there any way to hint at combine that ior is commutative without
having more permissive predicates?
--
PMatos