This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] Fix PR optimization/13653
- From: Eric Botcazou <ebotcazou at libertysurf dot fr>
- To: law at redhat dot com
- Cc: Richard Kenner <kenner at vlsi1 dot ultra dot nyu dot edu>,gcc-patches at gcc dot gnu dot org
- Date: Tue, 1 Jun 2004 08:32:02 +0200
- Subject: Re: [PATCH] Fix PR optimization/13653
- References: <10405262228.AA09440@vlsi1.ultra.nyu.edu> <200405271030.00262.ebotcazou@libertysurf.fr> <1086044813.3963.75.camel@speedy>
> Presumably the object we care about has TREE_READONLY set?
Yes (I already copy-pasted it in a previous message in this thread).
> But it's value varies from one iteration to the next (seems to me that
> if the value does not vary, then it could not have been a GIV).
It's a variable created at each loop iteration in an inlined constructor.
> Right. And presumably that's what's happening in this case -- ie, we
> have a reg which is set by the initialization in a loop and we're
> somehow determining that the initialization sequence looks like a GIV.
> And we're doing this even though we've set TREE_READONLY on the
> object. Right?
Yes, RTX_UNCHANGING_P is not taken into account when determining if a reg is
a GIV.
--
Eric Botcazou