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Re: SUBREGs
- To: law at cygnus dot com
- Subject: Re: SUBREGs
- From: "David S. Miller" <davem at dm dot cobaltmicro dot com>
- Date: Tue, 15 Sep 1998 22:45:45 -0700
- CC: amylaar at cygnus dot co dot uk, egcs at cygnus dot com
- References: <4669.905876385@hurl.cygnus.com>
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