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Re: i386 define_asm_attributes question

From: Jan Hubicka <hubicka at ucw dot cz>
To: "H.J. Lu" <hjl dot tools at gmail dot com>
Cc: Steven Bosscher <stevenb dot gcc at gmail dot com>, Jan Hubicha <jh at suse dot cz>, Uros Bizjak <ubizjak at gmail dot com>, GCC Mailing List <gcc at gcc dot gnu dot org>
Date: Tue, 8 May 2012 01:28:30 +0200
Subject: Re: i386 define_asm_attributes question
References: <CABu31nN5-K0NiZU9RyAbY-pFsQzPxQLhwa1D16i7PJ7yPrBF-w@mail.gmail.com> <CAMe9rOp9X=-3+EY8Q6MGju1ynVcWXhhwo6RAVqAPwVnnXHikWA@mail.gmail.com>

 >
> > Index: config/i386/i386.md
> > ===================================================================
> > --- config/i386/i386.md (revision 187257)
> > +++ config/i386/i386.md (working copy)
> > @@ -661,7 +661,7 @@
> >
> > ?;; Describe a user's asm statement.
> > ?(define_asm_attributes
> > - ?[(set_attr "length" "128")
> > + ?[(set_attr "length" "16")
> > ? ?(set_attr "type" "multi")])
> >
> > ?(define_code_iterator plusminus [plus minus])
> 
> I checked with our people.  The maximum insn length on Intel
> processor is 15byte.

The idea here was originally to prevent LOOP instruction to get out of bounds.
ASM statement even if they are single line may be arbitrary long and thus can
run out of the limits.
We don't produce length instructions anymore, where did you run into problem
with this setting?

Honza
> 
> -- 
> H.J.

Follow-Ups:
- Re: i386 define_asm_attributes question
  - From: Andrew Pinski
- Re: i386 define_asm_attributes question
  - From: Steven Bosscher

References:
- i386 define_asm_attributes question
  - From: Steven Bosscher
- Re: i386 define_asm_attributes question
  - From: H.J. Lu

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