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Re: (subreg:SF (reg:SC)) question - 20020227-1.c failure
- From: "John David Anglin" <dave at hiauly1 dot hia dot nrc dot ca>
- To: jh at suse dot cz (Jan Hubicka)
- Cc: weigand at immd1 dot informatik dot uni-erlangen dot de, jh at suse dot cz, gcc at gcc dot gnu dot org
- Date: Tue, 6 May 2003 21:41:12 -0400 (EDT)
- Subject: Re: (subreg:SF (reg:SC)) question - 20020227-1.c failure
> So you have (subreg:SF reg:SC 0) and nregs_multiple = 1, so you have
> single 64bit register holding the whole SC value. Why do you think you
> can access directly the upper part of it?
Both halves of a 64-bit floating point register are independently
addressable on the PA using loads, stores and copies. The upper
and lower halves of a general register can be accessed independently
using deposit and extract instructions.
The hppa64 port was done originally under the assumption that an
SCmode value could be held in a single 64-bit floating or general
register.
Dave
--
J. David Anglin dave.anglin@nrc-cnrc.gc.ca
National Research Council of Canada (613) 990-0752 (FAX: 952-6602)