From: Michael Matz <matz@suse.de>
To: Bernd Schmidt <bschmidt@redhat.com>
Cc: 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 13:18:00 -0000 [thread overview]
Message-ID: <alpine.LSU.2.20.1511251412400.11029@wotan.suse.de> (raw)
In-Reply-To: <56559121.6040208@redhat.com>
Hi,
On Wed, 25 Nov 2015, Bernd Schmidt 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?
Yes. Whenever it sees any unknown call (including mem barriers) it
forgets all known mem accesses (and hence can't mark accesses further down
as not trapping).
Ciao,
Michael.
next prev parent reply other threads:[~2015-11-25 13:17 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
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 [this message]
2015-11-25 10:36 ` Bernd Schmidt
2015-11-23 16:03 ` Michael Matz
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