Sharing hard registers

[Jan Hubicka]

>    From: Jan Hubicka <jh@suse.cz>
>    Date: Fri, 14 Jun 2002 11:59:16 +0200
>    
>    Pseudo registers are always shared.
> 
> I thought reload rewrites individual pseudo REG rtx expressions as it
> performs spills/reloads, and therefore each pseudo instance must be
> unique and not shared.

Hmm, it does not..  It is even documented in gccint.texi:

   * Each pseudo-register has only a single `reg' object to represent
     it, and therefore only a single machine mode.

Many parts of compiler rely on this fact.

Honza