Currently with G1 GC there are two types of archive-able heap regions, the open archive heap region and closed archive heap region. In open archive heap regions, objects within the region can have out-going references to other regions within the java heap. In JDK 10, the constant pool's resolved_references arrays (with resolved string constants) were supported to be cached in the open archive region at CDS dump time and used in subsequent JVM executions without recreating those array objects. The class mirror objects are good candidate for caching at CDS dump time. The mirrors will be stored in the open archive heap regions as the resolved_references arrays.
Support G1 GC, 64-bit (non-Windows). Requires UseCompressedOops and UseCompressedClassPointers.