hg: valhalla/valhalla: Summary: Add verifier checks for when a reference can and cannot be a value type

[harold.seigel at oracle.com]

Changeset: 1fbbc0ba4434
Author:    hseigel
Date:      2018-06-01 08:32 -0400
URL:       http://hg.openjdk.java.net/valhalla/valhalla/rev/1fbbc0ba4434

Summary: Add verifier checks for when a reference can and cannot be a value type
Reviewed-by: acorn

! src/hotspot/share/classfile/verifier.cpp
! test/hotspot/jtreg/runtime/valhalla/valuetypes/verifier/VerifierValueTypes.java
! test/hotspot/jtreg/runtime/valhalla/valuetypes/verifier/verifierTests.jcod