------- Comment #3 from sje at cup dot hp dot com 2009-02-24 00:01 -------
More work is needed then just setting flag_branch_target_optimize{,2}, we need
to define TARGET_BRANCH_TARGET_REGISTER_CLASS (return BR_REGS) and
TARGET_BRANCH_TARGET_REGISTER_CALLEE_SAVED (return 1) but even then it doesn't
seem to help. I think bt-load wants to move the load of the branch register up
but is constrained because we load it from a general register and we load the
general register just before loading the branch register. Unless bt-load tries
to move the load of the general register up it cannot move the load of the
branch register up and I don't think it will try to move the load of the
general register up because that is not what it is designed to do.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30688
