8147844: new method j.l.Runtime.onSpinWait() and the corresponding x86 hotspot instrinsic Summary: adds c1 & c2 x86 intrinsics for j.l.Runtime.onSpinWait() that utilize the PAUSE instruction Reviewed-by: iveresov, kvn Contributed-by: Ivan Krylov <ivan@azul.com>, Yuri Gaevsky <ygaevsky@azul.com>

8132718: Add tests which check that when humongous classloader object becomes unreachable it and all classes that were loaded in it should be collected Reviewed-by: jmasa, dfazunen

8153764: Add auxiliary method that generates class by class prototype to gc testlibrary Reviewed-by: dfazunen, iignatyev

8152949: Jigsaw crash when Klass in _fixup_module_field_list is unloaded Summary: During start up anonymous classes must be kept alive until after their mirror's module field is patched with java.base Reviewed-by: coleenp, hseigel Contributed-by: per.liden@oracle.com, stefan.karlsson@oracle.com

8154752: Cleanup initialization of G1Policy Reviewed-by: ehelin, tschatzl

8154745: Move default G1 pause time target setup to argument parsing Reviewed-by: ehelin, sjohanss

8154452: Deferred cleanups after split of G1CollectorPolicy code Reviewed-by: ehelin, sjohanss

8154467: Cleanup initialization of GCPolicyCounters Reviewed-by: ehelin, sjohanss

8053885: test/runtime/memory/RunUnitTestsConcurrently.java fails on solaris with largepage options Reviewed-by: jmasa, pliden

8154457: runtime/SharedArchiveFile/SharedStrings Shared string table stats missing Summary: Added more information when print out message reporting disabling the shared strings at CDS dump time. Reviewed-by: lfoltan, hseigel, mseledtsov, gtriantafill