Improve BLA and LOM tests

8234768: Shenandoah: Streamline enqueueing runtime barriers Reviewed-by: zgu

8234270: [REDO] JDK-8204128 NMT might report incorrect numbers for Compiler area Reviewed-by: stuefe, minqi

8234798: Build failure after atomic changes in JDK-8234563 Reviewed-by: tschatzl, rkennke, zgu

8234619: ZGC: gc/z/TestSmallHeap.java failure with Out Of Memory Reviewed-by: tschatzl, eosterlund

Merge

8234729: Javac should eagerly change code generation for method references to avert IllegalAccessError in future. Reviewed-by: mcimadamore

8221372: Test vmTestbase/nsk/jvmti/GetThreadState/thrstat001/TestDescription.java times out Summary: Update test to get rid of unneeded MethodEntry/MethodExit events Reviewed-by: amenkov, cjplummer

8179320: File.getUsableSpace() returns a negative number on very large file system Reviewed-by: alanb, rriggs, darcy

8234681: Remove UseJVMCIClassLoader logic from JVMCI code Reviewed-by: kvn, iignatyev

8234684: JFR crashes when rotating the JFR output during assertion failure Reviewed-by: egahlin, mseledtsov

8234359: [JVMCI] invalidate_nmethod_mirror shouldn't use a phantom reference Reviewed-by: kvn, eosterlund

8233197: Invert JvmtiExport::post_vm_initialized() and Jfr:on_vm_start() start-up order for correct option parsing Reviewed-by: sspitsyn, egahlin

8234531: Remove CMS code from CLDG and safepoint cleanup Reviewed-by: coleenp, zgu

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