SUBREGs

[David S. Miller]

   Date: Tue, 15 Sep 1998 10:19:45 -0600
   From: Jeffrey A Law <law@cygnus.com>

     In message <199809150945.KAA03265@phal.cygnus.co.uk>you write:
     > Even then, we have to be aware that only an unsigned quantity can
     > be relied on to describe the size of an object that is larger than
     > one half of the address space.

   I don't think we have to worry about such large values being held in
   a SUBREG/REG.  Seriously, do we really forsee a REG/SUBREG with a
   size that approaches 1/8 of the address space for the target?  That's
   a little absurd.

I think the original problem is that you could see a BLKmode SUBREG.

Or similarly, what about paradoxical and MEM subregging?

As an amusing side note, Richard and myself have pondered removing
SUBREGs entirely, and starting from scratch with a new RTL code named
CHMOD :-)

Later,
David S. Miller
davem@dm.cobaltmicro.com