------- Comment #8 from rakdver at kam dot mff dot cuni dot cz 2010-01-30
09:47 -------
Subject: Re: [4.3/4.4/4.5 regression] extra
spills due to RTL LICM
> (Looking at Zdenek:) Would something like this in a more polished and actually
> verified&tested form be a good idea?
I think this could cause us to move the invariant addresses out of the loop
unnecessarily. Note that moving "const(`g'+0x8)" out of the loop is only a
good idea because it is used elsewhere -- if it were only used as the address,
moving it out adds an unnecessary assignment. This could be handled by the
patch by ignoring the address invariants in find_invariants_to_move.
Otherwise, the idea looks fine to me (assuming that there are reasons why this
is not done by fwprop),
Zdenek
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39837
