--- a/src/share/vm/code/nmethod.hpp	Fri Oct 02 11:26:25 2009 -0700
+++ b/src/share/vm/code/nmethod.hpp	Fri Oct 09 15:18:52 2009 -0700
@@ -125,6 +125,7 @@
 class nmethod : public CodeBlob {
   friend class VMStructs;
   friend class NMethodSweeper;
+  friend class CodeCache;  // non-perm oops
  private:
   // Shared fields for all nmethod's
   static int _zombie_instruction_size;
@@ -132,7 +133,12 @@
   methodOop _method;
   int       _entry_bci;        // != InvocationEntryBci if this nmethod is an on-stack replacement method
 
-  nmethod*  _link;             // To support simple linked-list chaining of nmethods
+  // To support simple linked-list chaining of nmethods:
+  nmethod*  _osr_link;         // from instanceKlass::osr_nmethods_head
+  nmethod*  _scavenge_root_link; // from CodeCache::scavenge_root_nmethods
+
+  static nmethod* volatile _oops_do_mark_nmethods;
+  nmethod*        volatile _oops_do_mark_link;
 
   AbstractCompiler* _compiler; // The compiler which compiled this nmethod
 
@@ -174,6 +180,8 @@
   // used by jvmti to track if an unload event has been posted for this nmethod.
   bool _unload_reported;
 
+  jbyte _scavenge_root_state;
+
   NOT_PRODUCT(bool _has_debug_info; )
 
   // Nmethod Flushing lock (if non-zero, then the nmethod is not removed)
@@ -242,7 +250,6 @@
 
   // helper methods
   void* operator new(size_t size, int nmethod_size);
-  void check_store();
 
   const char* reloc_string_for(u_char* begin, u_char* end);
   void make_not_entrant_or_zombie(int state);
@@ -406,6 +413,24 @@
   int   version() const                           { return flags.version; }
   void  set_version(int v);
 
+  // Non-perm oop support
+  bool  on_scavenge_root_list() const                  { return (_scavenge_root_state & 1) != 0; }
+ protected:
+  enum { npl_on_list = 0x01, npl_marked = 0x10 };
+  void  set_on_scavenge_root_list()                    { _scavenge_root_state = npl_on_list; }
+  void  clear_on_scavenge_root_list()                  { _scavenge_root_state = 0; }
+  // assertion-checking and pruning logic uses the bits of _scavenge_root_state
+#ifndef PRODUCT
+  void  set_scavenge_root_marked()                     { _scavenge_root_state |= npl_marked; }
+  void  clear_scavenge_root_marked()                   { _scavenge_root_state &= ~npl_marked; }
+  bool  scavenge_root_not_marked()                     { return (_scavenge_root_state &~ npl_on_list) == 0; }
+  // N.B. there is no positive marked query, and we only use the not_marked query for asserts.
+#endif //PRODUCT
+  nmethod* scavenge_root_link() const                  { return _scavenge_root_link; }
+  void     set_scavenge_root_link(nmethod *n)          { _scavenge_root_link = n; }
+
+ public:
+
   // Sweeper support
   long  stack_traversal_mark()                    { return _stack_traversal_mark; }
   void  set_stack_traversal_mark(long l)          { _stack_traversal_mark = l; }
@@ -424,8 +449,8 @@
   int   osr_entry_bci() const                     { assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); return _entry_bci; }
   address  osr_entry() const                      { assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); return _osr_entry_point; }
   void  invalidate_osr_method();
-  nmethod* link() const                           { return _link; }
-  void     set_link(nmethod *n)                   { _link = n; }
+  nmethod* osr_link() const                       { return _osr_link; }
+  void     set_osr_link(nmethod *n)               { _osr_link = n; }
 
   // tells whether frames described by this nmethod can be deoptimized
   // note: native wrappers cannot be deoptimized.
@@ -465,7 +490,16 @@
 
   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map,
                                      OopClosure* f);
-  void oops_do(OopClosure* f);
+  virtual void oops_do(OopClosure* f) { oops_do(f, false); }
+  void         oops_do(OopClosure* f, bool do_strong_roots_only);
+  bool detect_scavenge_root_oops();
+  void verify_scavenge_root_oops() PRODUCT_RETURN;
+
+  bool test_set_oops_do_mark();
+  static void oops_do_marking_prologue();
+  static void oops_do_marking_epilogue();
+  static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
+  DEBUG_ONLY(bool test_oops_do_mark() { return _oops_do_mark_link != NULL; })
 
   // ScopeDesc for an instruction
   ScopeDesc* scope_desc_at(address pc);