hg: ppc-aix-port/jdk7u/hotspot: opto: explicit specification of rematerialization in ad file.

[goetz.lindenmaier at sap.com]

Changeset: e476a85349be
Author:    Goetz
Date:      2012-11-29 13:43 +0100
URL:       http://hg.openjdk.java.net/ppc-aix-port/jdk7u/hotspot/rev/e476a85349be

opto: explicit specification of rematerialization in ad file.

Introduce attributes "ins_cannot_rematerialize" and
"ins_should_rematerialize" to adl which allows/forbids
rematerialization.
If ins_cannot_rematerialize is set, the instruction will never
rematerialize.
If ins_should_rematerialize is set, adlc generates a rule for
the node that allows rematerialization.
See also MachNode::rematerialize().

This fixes a problem with rematerialization on PPC: constants
are rematerialized in a way that extends the live range of the
MachConstantBaseNode. This causes the assertion 'edge_from_to' in
Scheduling::verify_good_schedule() to fire.

! src/share/vm/adlc/formssel.cpp
! src/share/vm/adlc/output_h.cpp