This is the mail archive of the
cgen@sources.redhat.com
mailing list for the CGEN project.
Re: [RFA:] Fix lsb? bug with insn fields beyond base insn size.
- From: Hans-Peter Nilsson <hans-peter dot nilsson at axis dot com>
- To: dje at transmeta dot com
- Cc: hans-peter dot nilsson at axis dot com, cgen at sources dot redhat dot com
- Date: Mon, 24 Jun 2002 17:24:12 +0200
- Subject: Re: [RFA:] Fix lsb? bug with insn fields beyond base insn size.
> From: Doug Evans <dje@transmeta.com>
> Date: Wed, 19 Jun 2002 11:05:18 -0700 (PDT)
> Hans-Peter Nilsson writes:
> > This is a partial fix for what seems like a central problem:
> > bitfields are expressed as (start length) but whether "start" is
> > highest or lowest bit-number depends on "lsb0?".
> One alternative is to do the canonicalization at .cpu reading time,
> but that can also lead to confusion (causing people to revisit
> the issue again).
I'm mostly worried about bugs similar to those I found, with the
*internal* representation different for different "lsb?".
Though having the "external" (.cpu) representation different is
supposedly confusing more people than not (assuming that CGEN
attracts a larger audience than the current. ;-)
brgds, H-P