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From: Richard Biener <richard.guenther@gmail.com>
To: Bernd Schmidt <bschmidt@redhat.com>
Cc: Michael Matz <matz@suse.de>, Jeff Law <law@redhat.com>,
	GCC Patches <gcc-patches@gcc.gnu.org>,
		Jakub Jelinek <jakub@redhat.com>,
	Sebastian Pop <sebpop@gmail.com>
Subject: Re: Remove noce_mem_write_may_trap_or_fault_p in ifcvt
Date: Wed, 25 Nov 2015 11:53:00 -0000	[thread overview]
Message-ID: <CAFiYyc3jK7pEeVq1rQUX4m=uErByYuhx3qRw3M8gE0HH6w7SEQ@mail.gmail.com> (raw)
In-Reply-To: <56559121.6040208@redhat.com>

On Wed, Nov 25, 2015 at 11:44 AM, Bernd Schmidt <bschmidt@redhat.com> wrote:
> On 11/23/2015 05:05 PM, Michael Matz wrote:
>>
>>
>> It only does so under some conditions, amongst them if it sees a
>> dominating access to the same memory of the same type (load or store) and
>> size.  So it doesn't introduce writes on paths that don't already contain
>> a write, and hence are multi-thread safe.  Or, at least, that's the
>> intention.
>
>
> Does it also ensure there's no memory barrier in between?

I don't think so.  Btw, if you want to add this please add a new gimple
predicate to identify "memory barrier" (any call or asm with a VDEF).

Richard.

>
> Bernd
>

  reply	other threads:[~2015-11-25 11:38 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-06 17:21 Bernd Schmidt
2015-11-06 18:39 ` Jeff Law
2015-11-06 18:44   ` Bernd Schmidt
2015-11-06 19:20     ` Jeff Law
2015-11-06 19:30       ` Bernd Schmidt
2015-11-06 21:09         ` Jeff Law
2015-11-18 19:16           ` Bernd Schmidt
2015-11-18 23:49             ` Jeff Law
2015-11-20 14:09               ` Bernd Schmidt
2015-11-20 18:57                 ` Jeff Law
2015-11-23 16:07                   ` Michael Matz
2015-11-25 10:46                     ` Bernd Schmidt
2015-11-25 11:53                       ` Richard Biener [this message]
2015-11-25 13:18                         ` Michael Matz
2015-11-25 14:52                           ` Richard Biener
2015-11-25 15:02                             ` Jakub Jelinek
2015-11-25 15:18                               ` Michael Matz
2015-11-25 15:49                               ` Bernd Schmidt
2015-11-25 15:55                                 ` Michael Matz
2015-11-26  9:50                                   ` Richard Biener
2015-11-27 10:22                                     ` Bernd Schmidt
2015-11-25 13:18                       ` Michael Matz
2015-11-25 10:36                   ` Bernd Schmidt
2015-11-23 16:03                 ` Michael Matz

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