8012464: NMT: classes should not derive from _ValueObj, use VALUE_OBJ_CLASS_SPEC instead

NMT value objects should use VALUE_OBJ_CLASS_SPEC instead of deriving from _ValueObj

Reviewed-by: coleenp, hseigel, dholmes

hotspot/src/share/vm/services/memBaseline.hpp

@@ -133,7 +133,7 @@ typedef struct _memType2Name {
 
 
 // This class aggregates malloc'd records by memory type
-class MallocMem : public _ValueObj {
+class MallocMem VALUE_OBJ_CLASS_SPEC {
  private:
   MEMFLAGS       _type;
 
@@ -211,7 +211,7 @@ class ArenaMem : public MallocMem {
 };
 
 // This class aggregates virtual memory by its memory type
-class VMMem : public _ValueObj {
+class VMMem VALUE_OBJ_CLASS_SPEC {
  private:
   MEMFLAGS       _type;
 
@@ -296,7 +296,7 @@ class BaselineComparisonReporter;
  * aggregates memory usage by callsites when detail tracking
  * is on.
  */
-class MemBaseline : public _ValueObj {
+class MemBaseline VALUE_OBJ_CLASS_SPEC {
   friend class BaselineReporter;
   friend class BaselineComparisonReporter;
 

hotspot/src/share/vm/services/memPtr.hpp

@@ -89,7 +89,7 @@ class SequenceGenerator : AllStatic {
  * the memory pointer either points to a malloc'd
  * memory block, or a mmap'd memory block
  */
-class MemPointer : public _ValueObj {
+class MemPointer VALUE_OBJ_CLASS_SPEC {
  public:
   MemPointer(): _addr(0) { }
   MemPointer(address addr): _addr(addr) { }

hotspot/src/share/vm/services/memSnapshot.hpp

@@ -308,7 +308,7 @@ class VMRecordIterator : public MemPointerArrayIterator {
   }
 };
 
-class StagingArea : public _ValueObj {
+class StagingArea VALUE_OBJ_CLASS_SPEC {
  private:
   MemPointerArray*   _malloc_data;
   MemPointerArray*   _vm_data;

hotspot/src/share/vm/services/memTrackWorker.hpp

@@ -32,7 +32,7 @@
 // Maximum MAX_GENERATIONS generation data can be tracked.
 #define MAX_GENERATIONS  512
 
-class GenerationData : public _ValueObj {
+class GenerationData VALUE_OBJ_CLASS_SPEC {
  private:
   int           _number_of_classes;
   MemRecorder*  _recorder_list;