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Re: [PATCH] Make basic asm implicitly clobber memory, pr24414
- From: Bernd Edlinger <bernd dot edlinger at hotmail dot de>
- To: Bernd Schmidt <bschmidt at redhat dot com>, "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Cc: Richard Biener <rguenther at suse dot de>, Jeff Law <law at redhat dot com>
- Date: Wed, 9 Dec 2015 15:09:40 +0000
- Subject: Re: [PATCH] Make basic asm implicitly clobber memory, pr24414
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Hi,
On 09.12.2015 12:06 Bernd Schmidt wrote:
> On 12/09/2015 03:18 AM, Bernd Edlinger wrote:
>> Furthermore there is a documented use for asm(""): The empty
>> assembler string is used to make a function
>> volatile, thus calls can not be optimized away. But I think it is
>> not necessary to make this clobber anything,
>> nor should it be an instruction scheduling barrier, as it used to be
>> in the past.
>
> Making that change seems risky; best not to make assumptions about how
> these are used. In any case,
>
So would you agree on the general direction of the patch,
if I drop the hunk in sched-deps.c ?
Thanks
Bernd.