8369483: Cleanup dead code in HandleArea

Reviewed-by: fandreuzzi, stefank

Author: jsikstro

src/hotspot/share/runtime/handles.cpp

@@ -97,31 +97,26 @@ DEF_METADATA_HANDLE_FN_NOINLINE(method, Method)
 DEF_METADATA_HANDLE_FN_NOINLINE(constantPool, ConstantPool)
 
 
-static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
+static void chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
   oop* bottom = (oop*) chunk->bottom();
   oop* top    = (oop*) chunk_top;
-  uintx handles_visited = top - bottom;
   assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
-  // during GC phase 3, a handle may be a forward pointer that
-  // is not yet valid, so loosen the assertion
+
   while (bottom < top) {
     f->do_oop(bottom++);
   }
-  return handles_visited;
 }
 
 void HandleArea::oops_do(OopClosure* f) {
-  uintx handles_visited = 0;
   // First handle the current chunk. It is filled to the high water mark.
-  handles_visited += chunk_oops_do(f, _chunk, _hwm);
+  chunk_oops_do(f, _chunk, _hwm);
+
   // Then handle all previous chunks. They are completely filled.
   Chunk* k = _first;
   while(k != _chunk) {
-    handles_visited += chunk_oops_do(f, k, k->top());
+    chunk_oops_do(f, k, k->top());
     k = k->next();
   }
-
-  if (_prev != nullptr) _prev->oops_do(f);
 }
 
 void HandleMark::initialize(Thread* thread) {

src/hotspot/share/runtime/handles.hpp

@@ -184,13 +184,11 @@ class HandleArea: public Arena {
   int _handle_mark_nesting;
   int _no_handle_mark_nesting;
 #endif
-  HandleArea* _prev;          // link to outer (older) area
  public:
   // Constructor
-  HandleArea(MemTag mem_tag, HandleArea* prev) : Arena(mem_tag, Tag::tag_ha, Chunk::tiny_size) {
+  HandleArea(MemTag mem_tag) : Arena(mem_tag, Tag::tag_ha, Chunk::tiny_size) {
     DEBUG_ONLY(_handle_mark_nesting    = 0);
     DEBUG_ONLY(_no_handle_mark_nesting = 0);
-    _prev = prev;
   }
 
   // Handle allocation

src/hotspot/share/runtime/thread.cpp

@@ -74,7 +74,7 @@ Thread::Thread(MemTag mem_tag) {
   set_osthread(nullptr);
   set_resource_area(new (mem_tag) ResourceArea(mem_tag));
   DEBUG_ONLY(_current_resource_mark = nullptr;)
-  set_handle_area(new (mem_tag) HandleArea(mem_tag, nullptr));
+  set_handle_area(new (mem_tag) HandleArea(mem_tag));
   set_metadata_handles(new (mtClass) GrowableArray<Metadata*>(30, mtClass));
   set_last_handle_mark(nullptr);