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Date: Mon, 22 Nov 2021 14:40:16 +0800
From: Jojo R <rjiejie@linux.alibaba.com>
To: GCC Development <gcc@gcc.gnu.org>, Peter Bergner
 <bergner@linux.ibm.com>
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Subject: Re: How to describe
 =?utf-8?Q?=E2=80=98earlyclobber=E2=80=99_?=explicitly for specific
 source operand ?
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=E2=80=94 Jojo
=E5=9C=A8 2021=E5=B9=B411=E6=9C=8820=E6=97=A5 +0800 AM6:11=EF=BC=8CPeter =
Bergner <bergner=40linux.ibm.com>=EF=BC=8C=E5=86=99=E9=81=93=EF=BC=9A
> On 11/19/21 1:28 AM, Jojo R via Gcc wrote:
> > We know gcc supply earlyclobber function to avoid register overlap,
> >
> > but it can not describe explicitly for specific source operand, is it=
 right =3F
>
> You add the early clobber to the OUTPUT operand(s) that can clobber any=
 of the
> input source operands. You don't mark the source operands that could be=
 clobbered.
Yes, so we need to enhance the early clobber to cover this scene =3F
>
> Peter