This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: rs6000: PREFERRED_RELOAD_CLASS


> cc: gcc-patches@gcc.gnu.org
> Date: Fri, 21 Jul 2000 11:49:55 -0400
> From: David Edelsohn <dje@watson.ibm.com>
> 
> 	Won't this preference for DImode in GPRs prevent using FPRs for
> efficiently moving 64-bit objects on 32-bit systems?  There is a question
> about whether one wants to use an FPR if the OS support lazy saving.  Once
> one pays the price for using the FPR, one might as well use it for higher
> memory bandwidth of moves.

We explicitly ban keeping DImode values in FPRs on 32-bit systems,
in HARD_REGNO_MODE_OK.

-- 
- Geoffrey Keating <geoffk@cygnus.com>

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]