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Re: how to force reloader(?) to respect clobber directive?

From: Jan Hubicka <jh at suse dot cz>
To: Dimmy <diwil at mail dot ru>
Cc: Richard Henderson <rth at redhat dot com>, gcc at gcc dot gnu dot org
Date: Tue, 26 Feb 2002 20:34:16 +0100
Subject: Re: how to force reloader(?) to respect clobber directive?
References: <20020226121343.27800870.diwil@eis.ru> <20020226094456.A28494@redhat.com> <20020226232259.3189ab27.diwil@mail.ru>

> > On Tue, Feb 26, 2002 at 12:13:43PM +0300, Dmitry wrote:
> > > (define_insn "tstsi"
> > >   [(set (cc0) (match_operand:SI 0 "register_operand" "r"))
> > >         (clobber (match_dup 0))]
> > 
> > The constraint must be "+r" in this case.
My guess is that when expanding the insn you overwrite the input operand,
you should not.
In such situations you should probably use match_scratch construct to
get the output operand.

Honza
> > 
> > 
> > r~
> >

Follow-Ups:
- Re: how to force reloader(?) to respect clobber directive?
  - From: Dimmy

References:
- how to force reloader(?) to respect clobber directive?
  - From: Dmitry
- Re: how to force reloader(?) to respect clobber directive?
  - From: Richard Henderson
- Re: how to force reloader(?) to respect clobber directive?
  - From: Dimmy

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