This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Indirect memory addresses vs. lra
On Thu, Aug 08, 2019 at 01:57:41PM -0600, Jeff Law wrote:
Yea, it's certainly designed with the more mainstream architectures in
mind. THe double-indirect case that's being talked about here is well
out of the mainstream and not a feature of anything LRA has targetted to
date. So I'm not surprised it's not working.
My suggestion would be to ignore the double-indirect aspect of the
architecture right now, get the port working, then come back and try to
make double-indirect addressing modes work.
This sounds like sensible advice. However I wonder if this issue is
related to the other major outstanding problem I have, viz: the large
number of test failures which report "Unable to find a register to
spill" - So far, nobody has been able to explain how to solve that
issue and even the people who appear to be more knowlegeable have
expressed suprise that it is even happening at all.
Even if it should turn out not to be related, the message I've been
receiving in this thread is lra should not be expected to work for
non "mainstream" backends. So perhaps there is another, yet to be
discovered, restriction which prevents my backend from ever working?
On the other hand, given my lack of experience with gcc, it could be
that lra is working perfectly, and I have simply done something
incorrectly. But the uncertainty voiced in this thread means that it
is hard to be sure that I'm not trying to do something which is
currently unsupported.
J'
--
Avoid eavesdropping. Send strong encrypted email.
PGP Public key ID: 1024D/2DE827B3
fingerprint = 8797 A26D 0854 2EAB 0285 A290 8A67 719C 2DE8 27B3
See http://sks-keyservers.net or any PGP keyserver for public key.