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Re: LRA Vs match_scratch
- From: Claudiu Zissulescu <claziss at gmail dot com>
- To: Segher Boessenkool <segher at kernel dot crashing dot org>
- Cc: gcc at gcc dot gnu dot org
- Date: Sun, 16 Sep 2018 14:21:35 +0300
- Subject: Re: LRA Vs match_scratch
- References: <CAL0iMy2GaGMx6MKRn3tada=pzwL48OG5pYme1-CQex2PVZ_Ppw@mail.gmail.com> <20180911150047.GG23155@gate.crashing.org>
Hi Segher,
Sorry for the late reply...
Good to know that. I also observed some problems how we define
register classes for ARC. Please allow me to clean it a bit, and then
come back to you with this problem, if it is still there.
Thank you,
Claudiu
On Tue, Sep 11, 2018 at 6:00 PM Segher Boessenkool
<segher@kernel.crashing.org> wrote:
>
> Hi Claudiu,
>
> On Tue, Sep 04, 2018 at 11:11:44AM +0200, Claudiu Zissulescu wrote:
> > I am trying to get LRA fully working for ARC, but I've got an issue.
> > Whenever, LRA analyses an instruction having (clobber
> > (match_scratch:SI 3 "=X, ...)) in its pattern I hit the assert in
> > lra-constraints.c:4101, and it seems it has to do with the scratch's
> > 'X' constraint.
> > Do I miss something? Is there any limitation between LRA and scratch
> > operands having in their alternative 'X' constraint?
>
> There are other targets with =X in an alternative for a clobber match_scratch,
> like rs6000, and that does work fine with LRA. It doesn't hit that assert,
> anyway ;-)
>
> Do you have some debug output to show what is going on here?
>
>
> Segher