From: Tejas Belagod <tbelagod@arm.com>
To: rdsandiford@googlemail.com
Cc: "gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH][RFC] Bug handling SUBREG (MEM) - MEM having side-effects?
Date: Tue, 27 Nov 2012 10:24:00 -0000 [thread overview]
Message-ID: <50B494E1.7020303@arm.com> (raw)
In-Reply-To: <873907xjsc.fsf@talisman.default>
Richard Sandiford wrote:
>>
>> After the discussions Richard Earnshaw had on IRC with Andrew Pinski, it was
>> felt that it was best to fix the standard predicate
>> 'general_operand' to not allow SUBREG (MEM) with side-effects as it has known
>> issues associated with it - particularly reload not being able to deal with such
>> cases. 'general_operand' currently outlaws cases like paradoxical SUBREG (MEM)
>> on targets with insn scheduling and SUBREG (MEM) with non-zero SUBREG_BYTE. This
>> is another case it should not allow. Here is a patch that tightens
>> general_operands to not allow SUBREG (MEM) with MEM having side-effects.
>>
>> I would like to hear some thoughts on this.
>
> LGTM.
>
> It would be good to get rid of subreg mem operands altogether at some point,
> but that's a little too drastic for stage 3. This patch looks like a strict
> improvement.
>
Thanks for looking at this. Is this OK for 4.7 as well?
Tejas Belagod
ARM.
next prev parent reply other threads:[~2012-11-27 10:24 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-16 14:10 Tejas Belagod
2012-11-18 10:55 ` Richard Sandiford
2012-11-27 10:24 ` Tejas Belagod [this message]
2012-12-10 16:49 ` [PING][PATCH][RFC] " Tejas Belagod
2013-02-22 12:16 ` Tejas Belagod
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