[Bug rtl-optimization/54133] regrename introduces additional dependencies

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54133

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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--- Comment #6 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-08-02 07:21:50 UTC ---
> In experiment, if I disable r0/r1 from renaming, most regressions observed in
> CSiBE are gone.
> 
> So how should this be fixed? Thanks.

The choice of the renaming register can be parameterized at the class level,
but I'm not sure this would work here.  You could also try to add some
additional heuristics for this choice, as it seems to be clearly
counter-productive here.