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From: Eric Botcazou <ebotcazou@adacore.com>
To: Jakub Jelinek <jakub@redhat.com>
Cc: gcc-patches@gcc.gnu.org, Uros Bizjak <ubizjak@gmail.com>
Subject: Re: [PATCH] Avoid extending lifetime of likely spilled hard regs in ifcvt before reload (PR rtl-optimization/56484)
Date: Tue, 05 Mar 2013 17:28:00 -0000	[thread overview]
Message-ID: <3897593.89GmqB5X3k@polaris> (raw)
In-Reply-To: <20130305162646.GJ12913@tucnak.redhat.com>

> Without this patch, ifcvt extends lifetime of %eax hard register,
> which causes reload/LRA ICE later on.  Combiner and other passes try hard
> not to do that, even ifcvt has code for it if x is a hard register a few
> lines below it, but in this case the hard register is SET_SRC (set_b).
> 
> With this patch we just use the pseudo (x) which has been initialized
> from the hard register before the conditional.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
> 
> 2013-03-05  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR rtl-optimization/56484
> 	* ifcvt.c (noce_process_if_block): Before reload if else_bb
> 	is NULL, avoid extending lifetimes of hard registers in
> 	likely to spilled or small register classes.

ifcvt.c tests only small_register_classes_for_mode_p in the other places, so 
do you really need class_likely_spilled_p here?

-- 
Eric Botcazou

  parent reply	other threads:[~2013-03-05 17:28 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-05 16:27 Jakub Jelinek
2013-03-05 17:24 ` Jeff Law
2013-03-05 17:28 ` Eric Botcazou [this message]
2013-03-05 22:03   ` Jakub Jelinek
2013-03-05 22:33     ` Jakub Jelinek

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