7054512: Compress class pointers after perm gen removal

Summary: support of compress class pointers in the compilers.
Reviewed-by: kvn, twisti

42 files changed, 812 insertions, 356 deletions

diff --git a/src/share/vm/adlc/archDesc.cpp b/src/share/vm/adlc/archDesc.cpp
index 23cbb1e00..46e526402 100644
--- a/src/share/vm/adlc/archDesc.cpp
+++ b/src/share/vm/adlc/archDesc.cpp
@@ -968,7 +968,8 @@ void ArchDesc::initBaseOpTypes() {
   // Create InstructForm and assign type for each ideal instruction.
   for ( int j = _last_machine_leaf+1; j < _last_opcode; ++j) {
     char         *ident    = (char *)NodeClassNames[j];
-    if(!strcmp(ident, "ConI") || !strcmp(ident, "ConP") || !strcmp(ident, "ConN") ||
+    if(!strcmp(ident, "ConI") || !strcmp(ident, "ConP") ||
+       !strcmp(ident, "ConN") || !strcmp(ident, "ConNKlass") ||
        !strcmp(ident, "ConF") || !strcmp(ident, "ConD") ||
        !strcmp(ident, "ConL") || !strcmp(ident, "Con" ) ||
        !strcmp(ident, "Bool") ) {
diff --git a/src/share/vm/adlc/forms.cpp b/src/share/vm/adlc/forms.cpp
index 70b8bd962..fe1c95de7 100644
--- a/src/share/vm/adlc/forms.cpp
+++ b/src/share/vm/adlc/forms.cpp
@@ -215,6 +215,7 @@ Form::DataType Form::ideal_to_const_type(const char *name) const {
   if (strcmp(name,"ConI")==0) return Form::idealI;
   if (strcmp(name,"ConP")==0) return Form::idealP;
   if (strcmp(name,"ConN")==0) return Form::idealN;
+  if (strcmp(name,"ConNKlass")==0) return Form::idealNKlass;
   if (strcmp(name,"ConL")==0) return Form::idealL;
   if (strcmp(name,"ConF")==0) return Form::idealF;
   if (strcmp(name,"ConD")==0) return Form::idealD;
@@ -257,7 +258,7 @@ Form::DataType Form::is_load_from_memory(const char *opType) const {
   if( strcmp(opType,"LoadI")==0 )  return Form::idealI;
   if( strcmp(opType,"LoadUI2L")==0 )  return Form::idealI;
   if( strcmp(opType,"LoadKlass")==0 )  return Form::idealP;
-  if( strcmp(opType,"LoadNKlass")==0 ) return Form::idealN;
+  if( strcmp(opType,"LoadNKlass")==0 ) return Form::idealNKlass;
   if( strcmp(opType,"LoadL")==0 )  return Form::idealL;
   if( strcmp(opType,"LoadL_unaligned")==0 )  return Form::idealL;
   if( strcmp(opType,"LoadPLocked")==0 )  return Form::idealP;
@@ -280,6 +281,7 @@ Form::DataType Form::is_store_to_memory(const char *opType) const {
   if( strcmp(opType,"StoreL")==0)  return Form::idealL;
   if( strcmp(opType,"StoreP")==0)  return Form::idealP;
   if( strcmp(opType,"StoreN")==0)  return Form::idealN;
+  if( strcmp(opType,"StoreNKlass")==0)  return Form::idealNKlass;
   if( strcmp(opType,"StoreVector")==0 )  return Form::idealV;
   assert( strcmp(opType,"Store") != 0, "Must type Stores" );
   return Form::none;
diff --git a/src/share/vm/adlc/forms.hpp b/src/share/vm/adlc/forms.hpp
index aa13845d3..05871eca1 100644
--- a/src/share/vm/adlc/forms.hpp
+++ b/src/share/vm/adlc/forms.hpp
@@ -173,7 +173,8 @@ public:
     idealC      =  7,  // Char    type
     idealS      =  8,  // String  type
     idealN      =  9,  // Narrow oop types
-    idealV      = 10   // Vector  type
+    idealNKlass = 10,  // Narrow klass types
+    idealV      = 11   // Vector  type
   };
   // Convert ideal name to a DataType, return DataType::none if not a 'ConX'
   Form::DataType  ideal_to_const_type(const char *ideal_type_name) const;
diff --git a/src/share/vm/adlc/formssel.cpp b/src/share/vm/adlc/formssel.cpp
index 539bc3a7b..6ce713f57 100644
--- a/src/share/vm/adlc/formssel.cpp
+++ b/src/share/vm/adlc/formssel.cpp
@@ -746,14 +746,16 @@ int InstructForm::memory_operand(FormDict &globals) const {
 // Expected use is for pointer vs oop determination for LoadP
 bool InstructForm::captures_bottom_type(FormDict &globals) const {
   if( _matrule && _matrule->_rChild &&
-       (!strcmp(_matrule->_rChild->_opType,"CastPP")     ||  // new result type
-        !strcmp(_matrule->_rChild->_opType,"CastX2P")    ||  // new result type
-        !strcmp(_matrule->_rChild->_opType,"DecodeN")    ||
-        !strcmp(_matrule->_rChild->_opType,"EncodeP")    ||
-        !strcmp(_matrule->_rChild->_opType,"LoadN")      ||
-        !strcmp(_matrule->_rChild->_opType,"GetAndSetN") ||
-        !strcmp(_matrule->_rChild->_opType,"LoadNKlass") ||
-        !strcmp(_matrule->_rChild->_opType,"CreateEx")   ||  // type of exception
+       (!strcmp(_matrule->_rChild->_opType,"CastPP")       ||  // new result type
+        !strcmp(_matrule->_rChild->_opType,"CastX2P")      ||  // new result type
+        !strcmp(_matrule->_rChild->_opType,"DecodeN")      ||
+        !strcmp(_matrule->_rChild->_opType,"EncodeP")      ||
+        !strcmp(_matrule->_rChild->_opType,"DecodeNKlass") ||
+        !strcmp(_matrule->_rChild->_opType,"EncodePKlass") ||
+        !strcmp(_matrule->_rChild->_opType,"LoadN")        ||
+        !strcmp(_matrule->_rChild->_opType,"GetAndSetN")   ||
+        !strcmp(_matrule->_rChild->_opType,"LoadNKlass")   ||
+        !strcmp(_matrule->_rChild->_opType,"CreateEx")     ||  // type of exception
         !strcmp(_matrule->_rChild->_opType,"CheckCastPP")) ) return true;
   else if ( is_ideal_load() == Form::idealP )                return true;
   else if ( is_ideal_store() != Form::none  )                return true;
@@ -2452,6 +2454,7 @@ void OperandForm::format_constant(FILE *fp, uint const_index, uint const_type) {
   switch(const_type) {
   case Form::idealI:  fprintf(fp,"st->print(\"#%%d\", _c%d);\n", const_index); break;
   case Form::idealP:  fprintf(fp,"_c%d->dump_on(st);\n",         const_index); break;
+  case Form::idealNKlass:
   case Form::idealN:  fprintf(fp,"_c%d->dump_on(st);\n",         const_index); break;
   case Form::idealL:  fprintf(fp,"st->print(\"#%%lld\", _c%d);\n", const_index); break;
   case Form::idealF:  fprintf(fp,"st->print(\"#%%f\", _c%d);\n", const_index); break;
@@ -3390,7 +3393,7 @@ void MatchNode::output(FILE *fp) {
 
 int MatchNode::needs_ideal_memory_edge(FormDict &globals) const {
   static const char *needs_ideal_memory_list[] = {
-    "StoreI","StoreL","StoreP","StoreN","StoreD","StoreF" ,
+    "StoreI","StoreL","StoreP","StoreN","StoreNKlass","StoreD","StoreF" ,
     "StoreB","StoreC","Store" ,"StoreFP",
     "LoadI", "LoadUI2L", "LoadL", "LoadP" ,"LoadN", "LoadD" ,"LoadF"  ,
     "LoadB" , "LoadUB", "LoadUS" ,"LoadS" ,"Load" ,
@@ -3947,6 +3950,8 @@ int MatchRule::is_expensive() const {
         strcmp(opType,"ConvL2I")==0 ||
         strcmp(opType,"DecodeN")==0 ||
         strcmp(opType,"EncodeP")==0 ||
+        strcmp(opType,"EncodePKlass")==0 ||
+        strcmp(opType,"DecodeNKlass")==0 ||
         strcmp(opType,"RoundDouble")==0 ||
         strcmp(opType,"RoundFloat")==0 ||
         strcmp(opType,"ReverseBytesI")==0 ||
diff --git a/src/share/vm/adlc/output_c.cpp b/src/share/vm/adlc/output_c.cpp
index fe6ba16c8..794d73040 100644
--- a/src/share/vm/adlc/output_c.cpp
+++ b/src/share/vm/adlc/output_c.cpp
@@ -3644,6 +3644,8 @@ static void path_to_constant(FILE *fp, FormDict &globals,
       fprintf(fp, "_leaf->bottom_type()->is_ptr()");
     } else if ( (strcmp(optype,"ConN") == 0) ) {
       fprintf(fp, "_leaf->bottom_type()->is_narrowoop()");
+    } else if ( (strcmp(optype,"ConNKlass") == 0) ) {
+      fprintf(fp, "_leaf->bottom_type()->is_narrowklass()");
     } else if ( (strcmp(optype,"ConF") == 0) ) {
       fprintf(fp, "_leaf->getf()");
     } else if ( (strcmp(optype,"ConD") == 0) ) {
diff --git a/src/share/vm/adlc/output_h.cpp b/src/share/vm/adlc/output_h.cpp
index 8aea92871..e3debf2ea 100644
--- a/src/share/vm/adlc/output_h.cpp
+++ b/src/share/vm/adlc/output_h.cpp
@@ -207,6 +207,10 @@ static void declareConstStorage(FILE *fp, FormDict &globals, OperandForm *oper)
       if (i > 0) fprintf(fp,", ");
       fprintf(fp,"  const TypeNarrowOop *_c%d;\n", i);
     }
+    else if (!strcmp(type, "ConNKlass")) {
+      if (i > 0) fprintf(fp,", ");
+      fprintf(fp,"  const TypeNarrowKlass *_c%d;\n", i);
+    }
     else if (!strcmp(type, "ConL")) {
       if (i > 0) fprintf(fp,", ");
       fprintf(fp,"  jlong          _c%d;\n", i);
@@ -243,6 +247,10 @@ static void declareConstStorage(FILE *fp, FormDict &globals, OperandForm *oper)
         fprintf(fp,"  const TypePtr *_c%d;\n", i);
         i++;
       }
+      else if (!strcmp(comp->base_type(globals), "ConNKlass")) {
+        fprintf(fp,"  const TypePtr *_c%d;\n", i);
+        i++;
+      }
       else if (!strcmp(comp->base_type(globals), "ConL")) {
         fprintf(fp,"  jlong            _c%d;\n", i);
         i++;
@@ -288,11 +296,12 @@ static void defineConstructor(FILE *fp, const char *name, uint num_consts,
       fprintf(fp,is_ideal_bool ? "BoolTest::mask c%d" : "int32 c%d", i);
       break;
     }
-    case Form::idealN : { fprintf(fp,"const TypeNarrowOop *c%d", i); break; }
-    case Form::idealP : { fprintf(fp,"const TypePtr *c%d", i); break; }
-    case Form::idealL : { fprintf(fp,"jlong c%d", i);   break;        }
-    case Form::idealF : { fprintf(fp,"jfloat c%d", i);  break;        }
-    case Form::idealD : { fprintf(fp,"jdouble c%d", i); break;        }
+    case Form::idealN :      { fprintf(fp,"const TypeNarrowOop *c%d", i); break; }
+    case Form::idealNKlass : { fprintf(fp,"const TypeNarrowKlass *c%d", i); break; }
+    case Form::idealP :      { fprintf(fp,"const TypePtr *c%d", i); break; }
+    case Form::idealL :      { fprintf(fp,"jlong c%d", i);   break;        }
+    case Form::idealF :      { fprintf(fp,"jfloat c%d", i);  break;        }
+    case Form::idealD :      { fprintf(fp,"jdouble c%d", i); break;        }
     default:
       assert(!is_ideal_bool, "Non-constant operand lacks component list.");
       break;
@@ -316,6 +325,11 @@ static void defineConstructor(FILE *fp, const char *name, uint num_consts,
         fprintf(fp,"const TypePtr *c%d", i);
         i++;
       }
+      else if (!strcmp(comp->base_type(globals), "ConNKlass")) {
+        if (i > 0) fprintf(fp,", ");
+        fprintf(fp,"const TypePtr *c%d", i);
+        i++;
+      }
       else if (!strcmp(comp->base_type(globals), "ConL")) {
         if (i > 0) fprintf(fp,", ");
         fprintf(fp,"jlong c%d", i);
@@ -380,6 +394,10 @@ static uint dump_spec_constant(FILE *fp, const char *ideal_type, uint i, Operand
     fprintf(fp,"    _c%d->dump_on(st);\n", i);
     ++i;
   }
+  else if (!strcmp(ideal_type, "ConNKlass")) {
+    fprintf(fp,"    _c%d->dump_on(st);\n", i);
+    ++i;
+  }
   else if (!strcmp(ideal_type, "ConL")) {
     fprintf(fp,"    st->print(\"#\" INT64_FORMAT, _c%d);\n", i);
     ++i;
@@ -1239,7 +1257,7 @@ void ArchDesc::declareClasses(FILE *fp) {
       if( type != NULL ) {
         Form::DataType data_type = oper->is_base_constant(_globalNames);
         // Check if we are an ideal pointer type
-        if( data_type == Form::idealP || data_type == Form::idealN ) {
+        if( data_type == Form::idealP || data_type == Form::idealN || data_type == Form::idealNKlass ) {
           // Return the ideal type we already have: <TypePtr *>
           fprintf(fp," return _c0;");
         } else {
@@ -1377,6 +1395,16 @@ void ArchDesc::declareClasses(FILE *fp) {
           fprintf(fp,   " return _c0->get_ptrtype()->reloc();");
           fprintf(fp, " }\n");
         }
+        else if (!strcmp(oper->ideal_type(_globalNames), "ConNKlass")) {
+          // Access the locally stored constant
+          fprintf(fp,"  virtual intptr_t       constant() const {");
+          fprintf(fp,   " return _c0->get_ptrtype()->get_con();");
+          fprintf(fp, " }\n");
+          // Generate query to determine if this pointer is an oop
+          fprintf(fp,"  virtual relocInfo::relocType           constant_reloc() const {");
+          fprintf(fp,   " return _c0->get_ptrtype()->reloc();");
+          fprintf(fp, " }\n");
+        }
         else if (!strcmp(oper->ideal_type(_globalNames), "ConL")) {
           fprintf(fp,"  virtual intptr_t       constant() const {");
           // We don't support addressing modes with > 4Gig offsets.
@@ -1810,6 +1838,7 @@ void ArchDesc::declareClasses(FILE *fp) {
         break;
       case Form::idealP:
       case Form::idealN:
+      case Form::idealNKlass:
         fprintf(fp,"    return  opnd_array(1)->type();\n");
         break;
       case Form::idealD:
diff --git a/src/share/vm/c1/c1_LIRGenerator.cpp b/src/share/vm/c1/c1_LIRGenerator.cpp
index bea8b93ce..cf865f1b5 100644
--- a/src/share/vm/c1/c1_LIRGenerator.cpp
+++ b/src/share/vm/c1/c1_LIRGenerator.cpp
@@ -1286,7 +1286,7 @@ void LIRGenerator::do_getClass(Intrinsic* x) {
   if (x->needs_null_check()) {
     info = state_for(x);
   }
-  __ move(new LIR_Address(rcvr.result(), oopDesc::klass_offset_in_bytes(), UseCompressedKlassPointers ? T_OBJECT : T_ADDRESS), result, info);
+  __ move(new LIR_Address(rcvr.result(), oopDesc::klass_offset_in_bytes(), T_ADDRESS), result, info);
   __ move_wide(new LIR_Address(result, in_bytes(Klass::java_mirror_offset()), T_OBJECT), result);
 }
 
diff --git a/src/share/vm/ci/ciObjectFactory.cpp b/src/share/vm/ci/ciObjectFactory.cpp
index 3427bb8aa..5e1dc49f7 100644
--- a/src/share/vm/ci/ciObjectFactory.cpp
+++ b/src/share/vm/ci/ciObjectFactory.cpp
@@ -146,7 +146,7 @@ void ciObjectFactory::init_shared_objects() {
 
   for (int i = T_BOOLEAN; i <= T_CONFLICT; i++) {
     BasicType t = (BasicType)i;
-    if (type2name(t) != NULL && t != T_OBJECT && t != T_ARRAY && t != T_NARROWOOP) {
+    if (type2name(t) != NULL && t != T_OBJECT && t != T_ARRAY && t != T_NARROWOOP && t != T_NARROWKLASS) {
       ciType::_basic_types[t] = new (_arena) ciType(t);
       init_ident_of(ciType::_basic_types[t]);
     }
diff --git a/src/share/vm/classfile/classFileParser.cpp b/src/share/vm/classfile/classFileParser.cpp
index 5dcd87cc3..6b2a2f538 100644
--- a/src/share/vm/classfile/classFileParser.cpp
+++ b/src/share/vm/classfile/classFileParser.cpp
@@ -1008,40 +1008,42 @@ static FieldAllocationType _basic_type_to_atype[2 * (T_CONFLICT + 1)] = {
   BAD_ALLOCATION_TYPE, // 1
   BAD_ALLOCATION_TYPE, // 2
   BAD_ALLOCATION_TYPE, // 3
-  NONSTATIC_BYTE ,     // T_BOOLEAN  =  4,
-  NONSTATIC_SHORT,     // T_CHAR     =  5,
-  NONSTATIC_WORD,      // T_FLOAT    =  6,
-  NONSTATIC_DOUBLE,    // T_DOUBLE   =  7,
-  NONSTATIC_BYTE,      // T_BYTE     =  8,
-  NONSTATIC_SHORT,     // T_SHORT    =  9,
-  NONSTATIC_WORD,      // T_INT      = 10,
-  NONSTATIC_DOUBLE,    // T_LONG     = 11,
-  NONSTATIC_OOP,       // T_OBJECT   = 12,
-  NONSTATIC_OOP,       // T_ARRAY    = 13,
-  BAD_ALLOCATION_TYPE, // T_VOID     = 14,
-  BAD_ALLOCATION_TYPE, // T_ADDRESS  = 15,
-  BAD_ALLOCATION_TYPE, // T_NARROWOOP= 16,
-  BAD_ALLOCATION_TYPE, // T_METADATA = 17,
-  BAD_ALLOCATION_TYPE, // T_CONFLICT = 18,
+  NONSTATIC_BYTE ,     // T_BOOLEAN     =  4,
+  NONSTATIC_SHORT,     // T_CHAR        =  5,
+  NONSTATIC_WORD,      // T_FLOAT       =  6,
+  NONSTATIC_DOUBLE,    // T_DOUBLE      =  7,
+  NONSTATIC_BYTE,      // T_BYTE        =  8,
+  NONSTATIC_SHORT,     // T_SHORT       =  9,
+  NONSTATIC_WORD,      // T_INT         = 10,
+  NONSTATIC_DOUBLE,    // T_LONG        = 11,
+  NONSTATIC_OOP,       // T_OBJECT      = 12,
+  NONSTATIC_OOP,       // T_ARRAY       = 13,
+  BAD_ALLOCATION_TYPE, // T_VOID        = 14,
+  BAD_ALLOCATION_TYPE, // T_ADDRESS     = 15,
+  BAD_ALLOCATION_TYPE, // T_NARROWOOP   = 16,
+  BAD_ALLOCATION_TYPE, // T_METADATA    = 17,
+  BAD_ALLOCATION_TYPE, // T_NARROWKLASS = 18,
+  BAD_ALLOCATION_TYPE, // T_CONFLICT    = 19,
   BAD_ALLOCATION_TYPE, // 0
   BAD_ALLOCATION_TYPE, // 1
   BAD_ALLOCATION_TYPE, // 2
   BAD_ALLOCATION_TYPE, // 3
-  STATIC_BYTE ,        // T_BOOLEAN  =  4,
-  STATIC_SHORT,        // T_CHAR     =  5,
-  STATIC_WORD,          // T_FLOAT    =  6,
-  STATIC_DOUBLE,       // T_DOUBLE   =  7,
-  STATIC_BYTE,         // T_BYTE     =  8,
-  STATIC_SHORT,        // T_SHORT    =  9,
-  STATIC_WORD,         // T_INT      = 10,
-  STATIC_DOUBLE,       // T_LONG     = 11,
-  STATIC_OOP,          // T_OBJECT   = 12,
-  STATIC_OOP,          // T_ARRAY    = 13,
-  BAD_ALLOCATION_TYPE, // T_VOID     = 14,
-  BAD_ALLOCATION_TYPE, // T_ADDRESS  = 15,
-  BAD_ALLOCATION_TYPE, // T_NARROWOOP= 16,
-  BAD_ALLOCATION_TYPE, // T_METADATA = 17,
-  BAD_ALLOCATION_TYPE, // T_CONFLICT = 18,
+  STATIC_BYTE ,        // T_BOOLEAN     =  4,
+  STATIC_SHORT,        // T_CHAR        =  5,
+  STATIC_WORD,         // T_FLOAT       =  6,
+  STATIC_DOUBLE,       // T_DOUBLE      =  7,
+  STATIC_BYTE,         // T_BYTE        =  8,
+  STATIC_SHORT,        // T_SHORT       =  9,
+  STATIC_WORD,         // T_INT         = 10,
+  STATIC_DOUBLE,       // T_LONG        = 11,
+  STATIC_OOP,          // T_OBJECT      = 12,
+  STATIC_OOP,          // T_ARRAY       = 13,
+  BAD_ALLOCATION_TYPE, // T_VOID        = 14,
+  BAD_ALLOCATION_TYPE, // T_ADDRESS     = 15,
+  BAD_ALLOCATION_TYPE, // T_NARROWOOP   = 16,
+  BAD_ALLOCATION_TYPE, // T_METADATA    = 17,
+  BAD_ALLOCATION_TYPE, // T_NARROWKLASS = 18,
+  BAD_ALLOCATION_TYPE, // T_CONFLICT    = 19,
 };
 
 static FieldAllocationType basic_type_to_atype(bool is_static, BasicType type) {
diff --git a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
index 203821d2f..bc103b492 100644
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
+++ b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
@@ -222,7 +222,7 @@ ConcurrentMarkSweepGeneration::ConcurrentMarkSweepGeneration(
   // depends on this property.
   debug_only(
     FreeChunk* junk = NULL;
-    assert(UseCompressedOops ||
+    assert(UseCompressedKlassPointers ||
            junk->prev_addr() == (void*)(oop(junk)->klass_addr()),
            "Offset of FreeChunk::_prev within FreeChunk must match"
            "  that of OopDesc::_klass within OopDesc");
diff --git a/src/share/vm/memory/metaspace.hpp b/src/share/vm/memory/metaspace.hpp
index 077995a09..169a3b71d 100644
--- a/src/share/vm/memory/metaspace.hpp
+++ b/src/share/vm/memory/metaspace.hpp
@@ -135,6 +135,8 @@ class Metaspace : public CHeapObj<mtClass> {
   MetaWord* expand_and_allocate(size_t size,
                                 MetadataType mdtype);
 
+  static bool is_initialized() { return _class_space_list != NULL; }
+
 #ifndef PRODUCT
   bool contains(const void *ptr) const;
   bool contains_class(const void *ptr) const;
diff --git a/src/share/vm/memory/universe.cpp b/src/share/vm/memory/universe.cpp
index b2398259f..6ab3284af 100644
--- a/src/share/vm/memory/universe.cpp
+++ b/src/share/vm/memory/universe.cpp
@@ -151,7 +151,9 @@ size_t          Universe::_heap_used_at_last_gc = 0;
 
 CollectedHeap*  Universe::_collectedHeap = NULL;
 
-NarrowOopStruct Universe::_narrow_oop = { NULL, 0, true };
+NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
+NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
+address Universe::_narrow_ptrs_base;
 
 
 void Universe::basic_type_classes_do(void f(Klass*)) {
@@ -807,7 +809,7 @@ jint Universe::initialize_heap() {
     }
     if ((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) {
       // Can't reserve heap below 32Gb.
-      Universe::set_narrow_oop_base(Universe::heap()->base() - os::vm_page_size());
+      // keep the Universe::narrow_oop_base() set in Universe::reserve_heap()
       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
       if (verbose) {
         tty->print(", Compressed Oops with base: "PTR_FORMAT, Universe::narrow_oop_base());
@@ -838,8 +840,16 @@ jint Universe::initialize_heap() {
       tty->cr();
       tty->cr();
     }
+    if (UseCompressedKlassPointers) {
+      Universe::set_narrow_klass_base(Universe::narrow_oop_base());
+      Universe::set_narrow_klass_shift(MIN2(Universe::narrow_oop_shift(), LogKlassAlignmentInBytes));
+    }
+    Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
   }
-  assert(Universe::narrow_oop_base() == (Universe::heap()->base() - os::vm_page_size()) ||
+  // Universe::narrow_oop_base() is one page below the metaspace
+  // base. The actual metaspace base depends on alignment constraints
+  // so we don't know its exact location here.
+  assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() - os::vm_page_size() - ClassMetaspaceSize) ||
          Universe::narrow_oop_base() == NULL, "invalid value");
   assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
          Universe::narrow_oop_shift() == 0, "invalid value");
@@ -861,7 +871,10 @@ jint Universe::initialize_heap() {
 ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
   // Add in the class metaspace area so the classes in the headers can
   // be compressed the same as instances.
-  size_t total_reserved = align_size_up(heap_size + ClassMetaspaceSize, alignment);
+  // Need to round class space size up because it's below the heap and
+  // the actual alignment depends on its size.
+  size_t metaspace_size = align_size_up(ClassMetaspaceSize, alignment);
+  size_t total_reserved = align_size_up(heap_size + metaspace_size, alignment);
   char* addr = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop);
 
   ReservedHeapSpace total_rs(total_reserved, alignment, UseLargePages, addr);
@@ -895,11 +908,23 @@ ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
     return total_rs;
   }
 
-  // Split the reserved space into main Java heap and a space for classes
-  // so that they can be compressed using the same algorithm as compressed oops
-  ReservedSpace heap_rs = total_rs.first_part(heap_size);
-  ReservedSpace class_rs = total_rs.last_part(heap_size, alignment);
+  // Split the reserved space into main Java heap and a space for
+  // classes so that they can be compressed using the same algorithm
+  // as compressed oops. If compress oops and compress klass ptrs are
+  // used we need the meta space first: if the alignment used for
+  // compressed oops is greater than the one used for compressed klass
+  // ptrs, a metadata space on top of the heap could become
+  // unreachable.
+  ReservedSpace class_rs = total_rs.first_part(metaspace_size);
+  ReservedSpace heap_rs = total_rs.last_part(metaspace_size, alignment);
   Metaspace::initialize_class_space(class_rs);
+
+  if (UseCompressedOops) {
+    // Universe::initialize_heap() will reset this to NULL if unscaled
+    // or zero-based narrow oops are actually used.
+    address base = (address)(total_rs.base() - os::vm_page_size());
+    Universe::set_narrow_oop_base(base);
+  }
   return heap_rs;
 }
 
diff --git a/src/share/vm/memory/universe.hpp b/src/share/vm/memory/universe.hpp
index 818f9d340..12e0acb3c 100644
--- a/src/share/vm/memory/universe.hpp
+++ b/src/share/vm/memory/universe.hpp
@@ -105,16 +105,16 @@ class LatestMethodOopCache : public CommonMethodOopCache {
   Method* get_Method();
 };
 
-// For UseCompressedOops.
-struct NarrowOopStruct {
-  // Base address for oop-within-java-object materialization.
-  // NULL if using wide oops or zero based narrow oops.
+// For UseCompressedOops and UseCompressedKlassPointers.
+struct NarrowPtrStruct {
+  // Base address for oop/klass-within-java-object materialization.
+  // NULL if using wide oops/klasses or zero based narrow oops/klasses.
   address _base;
-  // Number of shift bits for encoding/decoding narrow oops.
-  // 0 if using wide oops or zero based unscaled narrow oops,
-  // LogMinObjAlignmentInBytes otherwise.
+  // Number of shift bits for encoding/decoding narrow ptrs.
+  // 0 if using wide ptrs or zero based unscaled narrow ptrs,
+  // LogMinObjAlignmentInBytes/LogKlassAlignmentInBytes otherwise.
   int     _shift;
-  // Generate code with implicit null checks for narrow oops.
+  // Generate code with implicit null checks for narrow ptrs.
   bool    _use_implicit_null_checks;
 };
 
@@ -206,7 +206,10 @@ class Universe: AllStatic {
   static CollectedHeap* _collectedHeap;
 
   // For UseCompressedOops.
-  static struct NarrowOopStruct _narrow_oop;
+  static struct NarrowPtrStruct _narrow_oop;
+  // For UseCompressedKlassPointers.
+  static struct NarrowPtrStruct _narrow_klass;
+  static address _narrow_ptrs_base;
 
   // array of dummy objects used with +FullGCAlot
   debug_only(static objArrayOop _fullgc_alot_dummy_array;)
@@ -259,8 +262,21 @@ class Universe: AllStatic {
     HeapBasedNarrowOop = 2
   };
   static char*    preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode);
-  static void     set_narrow_oop_base(address base)   { _narrow_oop._base  = base; }
-  static void     set_narrow_oop_use_implicit_null_checks(bool use) { _narrow_oop._use_implicit_null_checks = use; }
+  static char*    preferred_metaspace_base(size_t heap_size, NARROW_OOP_MODE mode);
+  static void     set_narrow_oop_base(address base) {
+    assert(UseCompressedOops, "no compressed oops?");
+    _narrow_oop._base    = base;
+  }
+  static void     set_narrow_klass_base(address base) {
+    assert(UseCompressedKlassPointers, "no compressed klass ptrs?");
+    _narrow_klass._base   = base;
+  }
+  static void     set_narrow_oop_use_implicit_null_checks(bool use) {
+    assert(UseCompressedOops, "no compressed ptrs?");
+    _narrow_oop._use_implicit_null_checks   = use;
+  }
+  static bool     reserve_metaspace_helper(bool with_base = false);
+  static ReservedHeapSpace reserve_heap_metaspace(size_t heap_size, size_t alignment, bool& contiguous);
 
   // Debugging
   static int _verify_count;                           // number of verifies done
@@ -354,14 +370,30 @@ class Universe: AllStatic {
   static CollectedHeap* heap() { return _collectedHeap; }
 
   // For UseCompressedOops
-  static address* narrow_oop_base_addr()              { return &_narrow_oop._base; }
-  static address  narrow_oop_base()                   { return  _narrow_oop._base; }
-  static bool  is_narrow_oop_base(void* addr)         { return (narrow_oop_base() == (address)addr); }
-  static int      narrow_oop_shift()                  { return  _narrow_oop._shift; }
-  static bool     narrow_oop_use_implicit_null_checks()             { return  _narrow_oop._use_implicit_null_checks; }
+  static address  narrow_oop_base()                       { return  _narrow_oop._base; }
+  static bool  is_narrow_oop_base(void* addr)             { return (narrow_oop_base() == (address)addr); }
+  static int      narrow_oop_shift()                      { return  _narrow_oop._shift; }
+  static bool     narrow_oop_use_implicit_null_checks()   { return  _narrow_oop._use_implicit_null_checks; }
+
+  // For UseCompressedKlassPointers
+  static address  narrow_klass_base()                     { return  _narrow_klass._base; }
+  static bool  is_narrow_klass_base(void* addr)           { return (narrow_klass_base() == (address)addr); }
+  static int      narrow_klass_shift()                    { return  _narrow_klass._shift; }
+  static bool     narrow_klass_use_implicit_null_checks() { return  _narrow_klass._use_implicit_null_checks; }
+
+  static address* narrow_ptrs_base_addr()                 { return &_narrow_ptrs_base; }
+  static void     set_narrow_ptrs_base(address a)         { _narrow_ptrs_base = a; }
+  static address  narrow_ptrs_base()                      { return _narrow_ptrs_base; }
 
   // this is set in vm_version on sparc (and then reset in universe afaict)
-  static void     set_narrow_oop_shift(int shift)     { _narrow_oop._shift = shift; }
+  static void     set_narrow_oop_shift(int shift)         {
+    _narrow_oop._shift   = shift;
+  }
+
+  static void     set_narrow_klass_shift(int shift)       {
+    assert(shift == 0 || shift == LogKlassAlignmentInBytes, "invalid shift for klass ptrs");
+    _narrow_klass._shift   = shift;
+  }
 
   // Reserve Java heap and determine CompressedOops mode
   static ReservedSpace reserve_heap(size_t heap_size, size_t alignment);
diff --git a/src/share/vm/oops/instanceOop.hpp b/src/share/vm/oops/instanceOop.hpp
index c608598c1..9ebb9d472 100644
--- a/src/share/vm/oops/instanceOop.hpp
+++ b/src/share/vm/oops/instanceOop.hpp
@@ -37,7 +37,9 @@ class instanceOopDesc : public oopDesc {
 
   // If compressed, the offset of the fields of the instance may not be aligned.
   static int base_offset_in_bytes() {
-    return UseCompressedKlassPointers ?
+    // offset computation code breaks if UseCompressedKlassPointers
+    // only is true
+    return (UseCompressedOops && UseCompressedKlassPointers) ?
              klass_gap_offset_in_bytes() :
              sizeof(instanceOopDesc);
   }
diff --git a/src/share/vm/oops/oop.inline.hpp b/src/share/vm/oops/oop.inline.hpp
index a9b532c7e..c09761747 100644
--- a/src/share/vm/oops/oop.inline.hpp
+++ b/src/share/vm/oops/oop.inline.hpp
@@ -185,8 +185,8 @@ inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
 inline bool check_obj_alignment(oop obj) {
   return (intptr_t)obj % MinObjAlignmentInBytes == 0;
 }
-inline bool check_obj_alignment(Klass* obj) {
-  return (intptr_t)obj % MinObjAlignmentInBytes == 0;
+inline bool check_klass_alignment(Klass* obj) {
+  return (intptr_t)obj % KlassAlignmentInBytes == 0;
 }
 
 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
@@ -228,9 +228,9 @@ inline oop oopDesc::decode_heap_oop(oop v)  { return v; }
 
 inline narrowOop oopDesc::encode_klass_not_null(Klass* v) {
   assert(!is_null(v), "oop value can never be zero");
-  assert(check_obj_alignment(v), "Address not aligned");
-  address base = Universe::narrow_oop_base();
-  int    shift = Universe::narrow_oop_shift();
+  assert(check_klass_alignment(v), "Address not aligned");
+  address base = Universe::narrow_klass_base();
+  int    shift = Universe::narrow_klass_shift();
   uint64_t  pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
   assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
   uint64_t result = pd >> shift;
@@ -245,10 +245,10 @@ inline narrowOop oopDesc::encode_klass(Klass* v) {
 
 inline Klass* oopDesc::decode_klass_not_null(narrowOop v) {
   assert(!is_null(v), "narrow oop value can never be zero");
-  address base = Universe::narrow_oop_base();
-  int    shift = Universe::narrow_oop_shift();
+  address base = Universe::narrow_klass_base();
+  int    shift = Universe::narrow_klass_shift();
   Klass* result = (Klass*)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
-  assert(check_obj_alignment(result), err_msg("address not aligned: " PTR_FORMAT, (void*) result));
+  assert(check_klass_alignment(result), err_msg("address not aligned: " PTR_FORMAT, (void*) result));
   return result;
 }
 
diff --git a/src/share/vm/opto/cfgnode.cpp b/src/share/vm/opto/cfgnode.cpp
index a85cd34c7..24d51afd2 100644
--- a/src/share/vm/opto/cfgnode.cpp
+++ b/src/share/vm/opto/cfgnode.cpp
@@ -1386,7 +1386,7 @@ static Node* split_flow_path(PhaseGVN *phase, PhiNode *phi) {
     Node *n = phi->in(i);
     if( !n ) return NULL;
     if( phase->type(n) == Type::TOP ) return NULL;
-    if( n->Opcode() == Op_ConP || n->Opcode() == Op_ConN )
+    if( n->Opcode() == Op_ConP || n->Opcode() == Op_ConN || n->Opcode() == Op_ConNKlass )
       break;
   }
   if( i >= phi->req() )         // Only split for constants
@@ -1875,17 +1875,19 @@ Node *PhiNode::Ideal(PhaseGVN *phase, bool can_reshape) {
   }
 
 #ifdef _LP64
-  // Push DecodeN down through phi.
+  // Push DecodeN/DecodeNKlass down through phi.
   // The rest of phi graph will transform by split EncodeP node though phis up.
-  if (UseCompressedOops && can_reshape && progress == NULL) {
+  if ((UseCompressedOops || UseCompressedKlassPointers) && can_reshape && progress == NULL) {
     bool may_push = true;
     bool has_decodeN = false;
+    bool is_decodeN = false;
     for (uint i=1; i<req(); ++i) {// For all paths in
       Node *ii = in(i);
-      if (ii->is_DecodeN() && ii->bottom_type() == bottom_type()) {
+      if (ii->is_DecodeNarrowPtr() && ii->bottom_type() == bottom_type()) {
         // Do optimization if a non dead path exist.
         if (ii->in(1)->bottom_type() != Type::TOP) {
           has_decodeN = true;
+          is_decodeN = ii->is_DecodeN();
         }
       } else if (!ii->is_Phi()) {
         may_push = false;
@@ -1895,13 +1897,18 @@ Node *PhiNode::Ideal(PhaseGVN *phase, bool can_reshape) {
     if (has_decodeN && may_push) {
       PhaseIterGVN *igvn = phase->is_IterGVN();
       // Make narrow type for new phi.
-      const Type* narrow_t = TypeNarrowOop::make(this->bottom_type()->is_ptr());
+      const Type* narrow_t;
+      if (is_decodeN) {
+        narrow_t = TypeNarrowOop::make(this->bottom_type()->is_ptr());
+      } else {
+        narrow_t = TypeNarrowKlass::make(this->bottom_type()->is_ptr());
+      }
       PhiNode* new_phi = new (phase->C) PhiNode(r, narrow_t);
       uint orig_cnt = req();
       for (uint i=1; i<req(); ++i) {// For all paths in
         Node *ii = in(i);
         Node* new_ii = NULL;
-        if (ii->is_DecodeN()) {
+        if (ii->is_DecodeNarrowPtr()) {
           assert(ii->bottom_type() == bottom_type(), "sanity");
           new_ii = ii->in(1);
         } else {
@@ -1909,14 +1916,22 @@ Node *PhiNode::Ideal(PhaseGVN *phase, bool can_reshape) {
           if (ii->as_Phi() == this) {
             new_ii = new_phi;
           } else {
-            new_ii = new (phase->C) EncodePNode(ii, narrow_t);
+            if (is_decodeN) {
+              new_ii = new (phase->C) EncodePNode(ii, narrow_t);
+            } else {
+              new_ii = new (phase->C) EncodePKlassNode(ii, narrow_t);
+            }
             igvn->register_new_node_with_optimizer(new_ii);
           }
         }
         new_phi->set_req(i, new_ii);
       }
       igvn->register_new_node_with_optimizer(new_phi, this);
-      progress = new (phase->C) DecodeNNode(new_phi, bottom_type());
+      if (is_decodeN) {
+        progress = new (phase->C) DecodeNNode(new_phi, bottom_type());
+      } else {
+        progress = new (phase->C) DecodeNKlassNode(new_phi, bottom_type());
+      }
     }
   }
 #endif
diff --git a/src/share/vm/opto/classes.hpp b/src/share/vm/opto/classes.hpp
index ea5ea33f4..c80c97460 100644
--- a/src/share/vm/opto/classes.hpp
+++ b/src/share/vm/opto/classes.hpp
@@ -91,6 +91,7 @@ macro(GetAndSetP)
 macro(GetAndSetN)
 macro(Con)
 macro(ConN)
+macro(ConNKlass)
 macro(ConD)
 macro(ConF)
 macro(ConI)
@@ -118,6 +119,7 @@ macro(CountTrailingZerosI)
 macro(CountTrailingZerosL)
 macro(CreateEx)
 macro(DecodeN)
+macro(DecodeNKlass)
 macro(DivD)
 macro(DivF)
 macro(DivI)
@@ -126,6 +128,7 @@ macro(DivMod)
 macro(DivModI)
 macro(DivModL)
 macro(EncodeP)
+macro(EncodePKlass)
 macro(ExpD)
 macro(FastLock)
 macro(FastUnlock)
@@ -233,6 +236,7 @@ macro(StoreI)
 macro(StoreL)
 macro(StoreP)
 macro(StoreN)
+macro(StoreNKlass)
 macro(StrComp)
 macro(StrEquals)
 macro(StrIndexOf)
diff --git a/src/share/vm/opto/compile.cpp b/src/share/vm/opto/compile.cpp
index cefd4674c..997687805 100644
--- a/src/share/vm/opto/compile.cpp
+++ b/src/share/vm/opto/compile.cpp
@@ -2239,6 +2239,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
           nop != Op_CreateEx &&
           nop != Op_CheckCastPP &&
           nop != Op_DecodeN &&
+          nop != Op_DecodeNKlass &&
           !n->is_Mem() ) {
         Node *x = n->clone();
         call->set_req( TypeFunc::Parms, x );
@@ -2287,6 +2288,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
   case Op_GetAndSetN:
   case Op_StoreP:
   case Op_StoreN:
+  case Op_StoreNKlass:
   case Op_LoadB:
   case Op_LoadUB:
   case Op_LoadUS:
@@ -2321,7 +2323,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
             "Base pointers must match" );
 #ifdef _LP64
-    if (UseCompressedOops &&
+    if ((UseCompressedOops || UseCompressedKlassPointers) &&
         addp->Opcode() == Op_ConP &&
         addp == n->in(AddPNode::Base) &&
         n->in(AddPNode::Offset)->is_Con()) {
@@ -2330,16 +2332,18 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
       // instructions (4) then load 64-bits constant (7).
       // Do this transformation here since IGVN will convert ConN back to ConP.
       const Type* t = addp->bottom_type();
-      if (t->isa_oopptr()) {
+      if (t->isa_oopptr() || t->isa_klassptr()) {
         Node* nn = NULL;
 
+        int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
+
         // Look for existing ConN node of the same exact type.
         Compile* C = Compile::current();
         Node* r  = C->root();
         uint cnt = r->outcnt();
         for (uint i = 0; i < cnt; i++) {
           Node* m = r->raw_out(i);
-          if (m!= NULL && m->Opcode() == Op_ConN &&
+          if (m!= NULL && m->Opcode() == op &&
               m->bottom_type()->make_ptr() == t) {
             nn = m;
             break;
@@ -2348,7 +2352,11 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
         if (nn != NULL) {
           // Decode a narrow oop to match address
           // [R12 + narrow_oop_reg<<3 + offset]
-          nn = new (C) DecodeNNode(nn, t);
+          if (t->isa_oopptr()) {
+            nn = new (C) DecodeNNode(nn, t);
+          } else {
+            nn = new (C) DecodeNKlassNode(nn, t);
+          }
           n->set_req(AddPNode::Base, nn);
           n->set_req(AddPNode::Address, nn);
           if (addp->outcnt() == 0) {
@@ -2403,22 +2411,24 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
   case Op_CmpP:
     // Do this transformation here to preserve CmpPNode::sub() and
     // other TypePtr related Ideal optimizations (for example, ptr nullness).
-    if (n->in(1)->is_DecodeN() || n->in(2)->is_DecodeN()) {
+    if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
       Node* in1 = n->in(1);
       Node* in2 = n->in(2);
-      if (!in1->is_DecodeN()) {
+      if (!in1->is_DecodeNarrowPtr()) {
         in2 = in1;
         in1 = n->in(2);
       }
-      assert(in1->is_DecodeN(), "sanity");
+      assert(in1->is_DecodeNarrowPtr(), "sanity");
 
       Compile* C = Compile::current();
       Node* new_in2 = NULL;
-      if (in2->is_DecodeN()) {
+      if (in2->is_DecodeNarrowPtr()) {
+        assert(in2->Opcode() == in1->Opcode(), "must be same node type");
         new_in2 = in2->in(1);
       } else if (in2->Opcode() == Op_ConP) {
         const Type* t = in2->bottom_type();
         if (t == TypePtr::NULL_PTR) {
+          assert(in1->is_DecodeN(), "compare klass to null?");
           // Don't convert CmpP null check into CmpN if compressed
           // oops implicit null check is not generated.
           // This will allow to generate normal oop implicit null check.
@@ -2463,6 +2473,8 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
           //
         } else if (t->isa_oopptr()) {
           new_in2 = ConNode::make(C, t->make_narrowoop());
+        } else if (t->isa_klassptr()) {
+          new_in2 = ConNode::make(C, t->make_narrowklass());
         }
       }
       if (new_in2 != NULL) {
@@ -2479,23 +2491,28 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
     break;
 
   case Op_DecodeN:
-    assert(!n->in(1)->is_EncodeP(), "should be optimized out");
+  case Op_DecodeNKlass:
+    assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
     // DecodeN could be pinned when it can't be fold into
     // an address expression, see the code for Op_CastPP above.
-    assert(n->in(0) == NULL || !Matcher::narrow_oop_use_complex_address(), "no control");
+    assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
     break;
 
-  case Op_EncodeP: {
+  case Op_EncodeP:
+  case Op_EncodePKlass: {
     Node* in1 = n->in(1);
-    if (in1->is_DecodeN()) {
+    if (in1->is_DecodeNarrowPtr()) {
       n->subsume_by(in1->in(1));
     } else if (in1->Opcode() == Op_ConP) {
       Compile* C = Compile::current();
       const Type* t = in1->bottom_type();
       if (t == TypePtr::NULL_PTR) {
+        assert(t->isa_oopptr(), "null klass?");
         n->subsume_by(ConNode::make(C, TypeNarrowOop::NULL_PTR));
       } else if (t->isa_oopptr()) {
         n->subsume_by(ConNode::make(C, t->make_narrowoop()));
+      } else if (t->isa_klassptr()) {
+        n->subsume_by(ConNode::make(C, t->make_narrowklass()));
       }
     }
     if (in1->outcnt() == 0) {
@@ -2529,7 +2546,7 @@ static void final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc ) {
   }
 
   case Op_Phi:
-    if (n->as_Phi()->bottom_type()->isa_narrowoop()) {
+    if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
       // The EncodeP optimization may create Phi with the same edges
       // for all paths. It is not handled well by Register Allocator.
       Node* unique_in = n->in(1);
@@ -2692,12 +2709,13 @@ static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Re
   }
 
   // Skip next transformation if compressed oops are not used.
-  if (!UseCompressedOops || !Matcher::gen_narrow_oop_implicit_null_checks())
+  if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
+      (!UseCompressedOops && !UseCompressedKlassPointers))
     return;
 
-  // Go over safepoints nodes to skip DecodeN nodes for debug edges.
+  // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
   // It could be done for an uncommon traps or any safepoints/calls
-  // if the DecodeN node is referenced only in a debug info.
+  // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
   while (sfpt.size() > 0) {
     n = sfpt.pop();
     JVMState *jvms = n->as_SafePoint()->jvms();
@@ -2708,7 +2726,7 @@ static void final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Re
                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
     for (int j = start; j < end; j++) {
       Node* in = n->in(j);
-      if (in->is_DecodeN()) {
+      if (in->is_DecodeNarrowPtr()) {
         bool safe_to_skip = true;
         if (!is_uncommon ) {
           // Is it safe to skip?
diff --git a/src/share/vm/opto/connode.cpp b/src/share/vm/opto/connode.cpp
index a2da3ee46..3ba08ae5c 100644
--- a/src/share/vm/opto/connode.cpp
+++ b/src/share/vm/opto/connode.cpp
@@ -45,16 +45,17 @@ uint ConNode::hash() const {
 //------------------------------make-------------------------------------------
 ConNode *ConNode::make( Compile* C, const Type *t ) {
   switch( t->basic_type() ) {
-  case T_INT:       return new (C) ConINode( t->is_int() );
-  case T_LONG:      return new (C) ConLNode( t->is_long() );
-  case T_FLOAT:     return new (C) ConFNode( t->is_float_constant() );
-  case T_DOUBLE:    return new (C) ConDNode( t->is_double_constant() );
-  case T_VOID:      return new (C) ConNode ( Type::TOP );
-  case T_OBJECT:    return new (C) ConPNode( t->is_ptr() );
-  case T_ARRAY:     return new (C) ConPNode( t->is_aryptr() );
-  case T_ADDRESS:   return new (C) ConPNode( t->is_ptr() );
-  case T_NARROWOOP: return new (C) ConNNode( t->is_narrowoop() );
-  case T_METADATA:  return new (C) ConPNode( t->is_ptr() );
+  case T_INT:         return new (C) ConINode( t->is_int() );
+  case T_LONG:        return new (C) ConLNode( t->is_long() );
+  case T_FLOAT:       return new (C) ConFNode( t->is_float_constant() );
+  case T_DOUBLE:      return new (C) ConDNode( t->is_double_constant() );
+  case T_VOID:        return new (C) ConNode ( Type::TOP );
+  case T_OBJECT:      return new (C) ConPNode( t->is_ptr() );
+  case T_ARRAY:       return new (C) ConPNode( t->is_aryptr() );
+  case T_ADDRESS:     return new (C) ConPNode( t->is_ptr() );
+  case T_NARROWOOP:   return new (C) ConNNode( t->is_narrowoop() );
+  case T_NARROWKLASS: return new (C) ConNKlassNode( t->is_narrowklass() );
+  case T_METADATA:    return new (C) ConPNode( t->is_ptr() );
     // Expected cases:  TypePtr::NULL_PTR, any is_rawptr()
     // Also seen: AnyPtr(TopPTR *+top); from command line:
     //   r -XX:+PrintOpto -XX:CIStart=285 -XX:+CompileTheWorld -XX:CompileTheWorldStartAt=660
@@ -447,7 +448,7 @@ Node *ConstraintCastNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
 // If not converting int->oop, throw away cast after constant propagation
 Node *CastPPNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
   const Type *t = ccp->type(in(1));
-  if (!t->isa_oop_ptr() || (in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks())) {
+  if (!t->isa_oop_ptr() || ((in(1)->is_DecodeN()) && Matcher::gen_narrow_oop_implicit_null_checks())) {
     return NULL; // do not transform raw pointers or narrow oops
   }
   return ConstraintCastNode::Ideal_DU_postCCP(ccp);
@@ -607,15 +608,56 @@ const Type *EncodePNode::Value( PhaseTransform *phase ) const {
   if (t == Type::TOP) return Type::TOP;
   if (t == TypePtr::NULL_PTR) return TypeNarrowOop::NULL_PTR;
 
-  assert(t->isa_oop_ptr() || UseCompressedKlassPointers && t->isa_klassptr(), "only oopptr here");
+  assert(t->isa_oop_ptr(), "only oopptr here");
   return t->make_narrowoop();
 }
 
 
-Node *EncodePNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
+Node *EncodeNarrowPtrNode::Ideal_DU_postCCP( PhaseCCP *ccp ) {
   return MemNode::Ideal_common_DU_postCCP(ccp, this, in(1));
 }
 
+Node* DecodeNKlassNode::Identity(PhaseTransform* phase) {
+  const Type *t = phase->type( in(1) );
+  if( t == Type::TOP ) return in(1);
+
+  if (in(1)->is_EncodePKlass()) {
+    // (DecodeNKlass (EncodePKlass p)) -> p
+    return in(1)->in(1);
+  }
+  return this;
+}
+
+const Type *DecodeNKlassNode::Value( PhaseTransform *phase ) const {
+  const Type *t = phase->type( in(1) );
+  if (t == Type::TOP) return Type::TOP;
+  assert(t != TypeNarrowKlass::NULL_PTR, "null klass?");
+
+  assert(t->isa_narrowklass(), "only narrow klass ptr here");
+  return t->make_ptr();
+}
+
+Node* EncodePKlassNode::Identity(PhaseTransform* phase) {
+  const Type *t = phase->type( in(1) );
+  if( t == Type::TOP ) return in(1);
+
+  if (in(1)->is_DecodeNKlass()) {
+    // (EncodePKlass (DecodeNKlass p)) -> p
+    return in(1)->in(1);
+  }
+  return this;
+}
+
+const Type *EncodePKlassNode::Value( PhaseTransform *phase ) const {
+  const Type *t = phase->type( in(1) );
+  if (t == Type::TOP) return Type::TOP;
+  assert (t != TypePtr::NULL_PTR, "null klass?");
+
+  assert(UseCompressedKlassPointers && t->isa_klassptr(), "only klass ptr here");
+  return t->make_narrowklass();
+}
+
+
 //=============================================================================
 //------------------------------Identity---------------------------------------
 Node *Conv2BNode::Identity( PhaseTransform *phase ) {
diff --git a/src/share/vm/opto/connode.hpp b/src/share/vm/opto/connode.hpp
index 2f8c79aac..d7a856ade 100644
--- a/src/share/vm/opto/connode.hpp
+++ b/src/share/vm/opto/connode.hpp
@@ -88,6 +88,14 @@ public:
   virtual int Opcode() const;
 };
 
+//------------------------------ConNKlassNode---------------------------------
+// Simple narrow klass constants
+class ConNKlassNode : public ConNode {
+public:
+  ConNKlassNode( const TypeNarrowKlass *t ) : ConNode(t) {}
+  virtual int Opcode() const;
+};
+
 
 //------------------------------ConLNode---------------------------------------
 // Simple long constants
@@ -270,42 +278,91 @@ public:
 };
 
 
+//------------------------------EncodeNarrowPtr--------------------------------
+class EncodeNarrowPtrNode : public TypeNode {
+ protected:
+  EncodeNarrowPtrNode(Node* value, const Type* type):
+    TypeNode(type, 2) {
+    init_class_id(Class_EncodeNarrowPtr);
+    init_req(0, NULL);
+    init_req(1, value);
+  }
+ public:
+  virtual uint  ideal_reg() const { return Op_RegN; }
+  virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
+};
+
 //------------------------------EncodeP--------------------------------
 // Encodes an oop pointers into its compressed form
 // Takes an extra argument which is the real heap base as a long which
 // may be useful for code generation in the backend.
-class EncodePNode : public TypeNode {
+class EncodePNode : public EncodeNarrowPtrNode {
  public:
   EncodePNode(Node* value, const Type* type):
-    TypeNode(type, 2) {
+    EncodeNarrowPtrNode(value, type) {
     init_class_id(Class_EncodeP);
-    init_req(0, NULL);
-    init_req(1, value);
   }
   virtual int Opcode() const;
   virtual Node *Identity( PhaseTransform *phase );
   virtual const Type *Value( PhaseTransform *phase ) const;
-  virtual uint  ideal_reg() const { return Op_RegN; }
+};
 
-  virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
+//------------------------------EncodePKlass--------------------------------
+// Encodes a klass pointer into its compressed form
+// Takes an extra argument which is the real heap base as a long which
+// may be useful for code generation in the backend.
+class EncodePKlassNode : public EncodeNarrowPtrNode {
+ public:
+  EncodePKlassNode(Node* value, const Type* type):
+    EncodeNarrowPtrNode(value, type) {
+    init_class_id(Class_EncodePKlass);
+  }
+  virtual int Opcode() const;
+  virtual Node *Identity( PhaseTransform *phase );
+  virtual const Type *Value( PhaseTransform *phase ) const;
+};
+
+//------------------------------DecodeNarrowPtr--------------------------------
+class DecodeNarrowPtrNode : public TypeNode {
+ protected:
+  DecodeNarrowPtrNode(Node* value, const Type* type):
+    TypeNode(type, 2) {
+    init_class_id(Class_DecodeNarrowPtr);
+    init_req(0, NULL);
+    init_req(1, value);
+  }
+ public:
+  virtual uint  ideal_reg() const { return Op_RegP; }
 };
 
 //------------------------------DecodeN--------------------------------
 // Converts a narrow oop into a real oop ptr.
 // Takes an extra argument which is the real heap base as a long which
 // may be useful for code generation in the backend.
-class DecodeNNode : public TypeNode {
+class DecodeNNode : public DecodeNarrowPtrNode {
  public:
   DecodeNNode(Node* value, const Type* type):
-    TypeNode(type, 2) {
+    DecodeNarrowPtrNode(value, type) {
     init_class_id(Class_DecodeN);
-    init_req(0, NULL);
-    init_req(1, value);
   }
   virtual int Opcode() const;
+  virtual const Type *Value( PhaseTransform *phase ) const;
   virtual Node *Identity( PhaseTransform *phase );
+};
+
+//------------------------------DecodeNKlass--------------------------------
+// Converts a narrow klass pointer into a real klass ptr.
+// Takes an extra argument which is the real heap base as a long which
+// may be useful for code generation in the backend.
+class DecodeNKlassNode : public DecodeNarrowPtrNode {
+ public:
+  DecodeNKlassNode(Node* value, const Type* type):
+    DecodeNarrowPtrNode(value, type) {
+    init_class_id(Class_DecodeNKlass);
+  }
+  virtual int Opcode() const;
   virtual const Type *Value( PhaseTransform *phase ) const;
-  virtual uint  ideal_reg() const { return Op_RegP; }
+  virtual Node *Identity( PhaseTransform *phase );
 };
 
 //------------------------------Conv2BNode-------------------------------------
diff --git a/src/share/vm/opto/escape.cpp b/src/share/vm/opto/escape.cpp
index 85d40b0d3..9fd318050 100644
--- a/src/share/vm/opto/escape.cpp
+++ b/src/share/vm/opto/escape.cpp
@@ -368,7 +368,9 @@ void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *de
     case Op_CastPP:
     case Op_CheckCastPP:
     case Op_EncodeP:
-    case Op_DecodeN: {
+    case Op_DecodeN:
+    case Op_EncodePKlass:
+    case Op_DecodeNKlass: {
       add_local_var_and_edge(n, PointsToNode::NoEscape,
                              n->in(1), delayed_worklist);
       break;
@@ -381,7 +383,8 @@ void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *de
       break;
     }
     case Op_ConP:
-    case Op_ConN: {
+    case Op_ConN:
+    case Op_ConNKlass: {
       // assume all oop constants globally escape except for null
       PointsToNode::EscapeState es;
       if (igvn->type(n) == TypePtr::NULL_PTR ||
@@ -458,6 +461,7 @@ void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *de
     }
     case Op_StoreP:
     case Op_StoreN:
+    case Op_StoreNKlass:
     case Op_StorePConditional:
     case Op_CompareAndSwapP:
     case Op_CompareAndSwapN: {
@@ -465,7 +469,7 @@ void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *de
       const Type *adr_type = igvn->type(adr);
       adr_type = adr_type->make_ptr();
       if (adr_type->isa_oopptr() ||
-          (opcode == Op_StoreP || opcode == Op_StoreN) &&
+          (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
                         (adr_type == TypeRawPtr::NOTNULL &&
                          adr->in(AddPNode::Address)->is_Proj() &&
                          adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
@@ -572,7 +576,9 @@ void ConnectionGraph::add_final_edges(Node *n) {
     case Op_CastPP:
     case Op_CheckCastPP:
     case Op_EncodeP:
-    case Op_DecodeN: {
+    case Op_DecodeN:
+    case Op_EncodePKlass:
+    case Op_DecodeNKlass: {
       add_local_var_and_edge(n, PointsToNode::NoEscape,
                              n->in(1), NULL);
       break;
@@ -646,6 +652,7 @@ void ConnectionGraph::add_final_edges(Node *n) {
     }
     case Op_StoreP:
     case Op_StoreN:
+    case Op_StoreNKlass:
     case Op_StorePConditional:
     case Op_CompareAndSwapP:
     case Op_CompareAndSwapN:
@@ -661,7 +668,7 @@ void ConnectionGraph::add_final_edges(Node *n) {
       const Type *adr_type = _igvn->type(adr);
       adr_type = adr_type->make_ptr();
       if (adr_type->isa_oopptr() ||
-          (opcode == Op_StoreP || opcode == Op_StoreN) &&
+          (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
                         (adr_type == TypeRawPtr::NOTNULL &&
                          adr->in(AddPNode::Address)->is_Proj() &&
                          adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
@@ -2088,7 +2095,7 @@ Node* ConnectionGraph::get_addp_base(Node *addp) {
     Node* uncast_base = base->uncast();
     int opcode = uncast_base->Opcode();
     assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
-           opcode == Op_CastX2P || uncast_base->is_DecodeN() ||
+           opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
            (uncast_base->is_Mem() && uncast_base->bottom_type() == TypeRawPtr::NOTNULL) ||
            (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity");
   }
@@ -2837,8 +2844,8 @@ void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist)
         alloc_worklist.append_if_missing(use);
       } else if (use->is_Phi() ||
                  use->is_CheckCastPP() ||
-                 use->is_EncodeP() ||
-                 use->is_DecodeN() ||
+                 use->is_EncodeNarrowPtr() ||
+                 use->is_DecodeNarrowPtr() ||
                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
         alloc_worklist.append_if_missing(use);
 #ifdef ASSERT
diff --git a/src/share/vm/opto/lcm.cpp b/src/share/vm/opto/lcm.cpp
index 4cca9c580..24a6a3182 100644
--- a/src/share/vm/opto/lcm.cpp
+++ b/src/share/vm/opto/lcm.cpp
@@ -164,6 +164,7 @@ void Block::implicit_null_check(PhaseCFG *cfg, Node *proj, Node *val, int allowe
     case Op_StoreL:
     case Op_StoreP:
     case Op_StoreN:
+    case Op_StoreNKlass:
       was_store = true;         // Memory op is a store op
       // Stores will have their address in slot 2 (memory in slot 1).
       // If the value being nul-checked is in another slot, it means we
diff --git a/src/share/vm/opto/library_call.cpp b/src/share/vm/opto/library_call.cpp
index 4ba7e127e..e733365dd 100644
--- a/src/share/vm/opto/library_call.cpp
+++ b/src/share/vm/opto/library_call.cpp
@@ -4383,7 +4383,7 @@ void LibraryCallKit::copy_to_clone(Node* obj, Node* alloc_obj, Node* obj_size, b
   // 12 - 64-bit VM, compressed klass
   // 16 - 64-bit VM, normal klass
   if (base_off % BytesPerLong != 0) {
-    assert(UseCompressedOops, "");
+    assert(UseCompressedKlassPointers, "");
     if (is_array) {
       // Exclude length to copy by 8 bytes words.
       base_off += sizeof(int);
diff --git a/src/share/vm/opto/live.cpp b/src/share/vm/opto/live.cpp
index cdeed3b1f..5da418915 100644
--- a/src/share/vm/opto/live.cpp
+++ b/src/share/vm/opto/live.cpp
@@ -331,6 +331,7 @@ void PhaseChaitin::verify_base_ptrs( ResourceArea *a ) const {
 #ifdef _LP64
                       UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_CastPP ||
                       UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_DecodeN ||
+                      UseCompressedKlassPointers && check->as_Mach()->ideal_Opcode() == Op_DecodeNKlass ||
 #endif
                       check->as_Mach()->ideal_Opcode() == Op_LoadP ||
                       check->as_Mach()->ideal_Opcode() == Op_LoadKlass)) {
diff --git a/src/share/vm/opto/loopTransform.cpp b/src/share/vm/opto/loopTransform.cpp
index 207ccbbb0..f145079a1 100644
--- a/src/share/vm/opto/loopTransform.cpp
+++ b/src/share/vm/opto/loopTransform.cpp
@@ -2413,7 +2413,7 @@ bool PhaseIdealLoop::match_fill_loop(IdealLoopTree* lpt, Node*& store, Node*& st
         break;
       }
       int opc = n->Opcode();
-      if (opc == Op_StoreP || opc == Op_StoreN || opc == Op_StoreCM) {
+      if (opc == Op_StoreP || opc == Op_StoreN || opc == Op_StoreNKlass || opc == Op_StoreCM) {
         msg = "oop fills not handled";
         break;
       }
diff --git a/src/share/vm/opto/loopopts.cpp b/src/share/vm/opto/loopopts.cpp
index 5c49a0444..9c8114734 100644
--- a/src/share/vm/opto/loopopts.cpp
+++ b/src/share/vm/opto/loopopts.cpp
@@ -550,7 +550,7 @@ Node *PhaseIdealLoop::conditional_move( Node *region ) {
     // This will likely Split-If, a higher-payoff operation.
     for (DUIterator_Fast kmax, k = phi->fast_outs(kmax); k < kmax; k++) {
       Node* use = phi->fast_out(k);
-      if (use->is_Cmp() || use->is_DecodeN() || use->is_EncodeP())
+      if (use->is_Cmp() || use->is_DecodeNarrowPtr() || use->is_EncodeNarrowPtr())
         cost += ConditionalMoveLimit;
       // Is there a use inside the loop?
       // Note: check only basic types since CMoveP is pinned.
@@ -1006,7 +1006,7 @@ void PhaseIdealLoop::split_if_with_blocks_post( Node *n ) {
             // to fold a StoreP and an AddP together (as part of an
             // address expression) and the AddP and StoreP have
             // different controls.
-            if( !x->is_Load() && !x->is_DecodeN() ) _igvn._worklist.yank(x);
+            if (!x->is_Load() && !x->is_DecodeNarrowPtr()) _igvn._worklist.yank(x);
           }
           _igvn.remove_dead_node(n);
         }
diff --git a/src/share/vm/opto/machnode.cpp b/src/share/vm/opto/machnode.cpp
index 2a5d96369..30970102d 100644
--- a/src/share/vm/opto/machnode.cpp
+++ b/src/share/vm/opto/machnode.cpp
@@ -265,7 +265,8 @@ const Node* MachNode::get_base_and_disp(intptr_t &offset, const TypePtr* &adr_ty
     // See if it adds up to a base + offset.
     if (index != NULL) {
       const Type* t_index = index->bottom_type();
-      if (t_index->isa_narrowoop()) { // EncodeN, LoadN, LoadConN, LoadNKlass.
+      if (t_index->isa_narrowoop() || t_index->isa_narrowklass()) { // EncodeN, LoadN, LoadConN, LoadNKlass,
+                                                                    // EncodeNKlass, LoadConNklass.
         // Memory references through narrow oops have a
         // funny base so grab the type from the index:
         // [R12 + narrow_oop_reg<<3 + offset]
@@ -352,6 +353,10 @@ const class TypePtr *MachNode::adr_type() const {
     // 32-bit unscaled narrow oop can be the base of any address expression
     t = t->make_ptr();
   }
+  if (UseCompressedKlassPointers && Universe::narrow_klass_shift() == 0) {
+    // 32-bit unscaled narrow oop can be the base of any address expression
+    t = t->make_ptr();
+  }
   if (t->isa_intptr_t() && offset != 0 && offset != Type::OffsetBot) {
     // We cannot assert that the offset does not look oop-ish here.
     // Depending on the heap layout the cardmark base could land
diff --git a/src/share/vm/opto/macro.cpp b/src/share/vm/opto/macro.cpp
index 90f1f0299..16987d974 100644
--- a/src/share/vm/opto/macro.cpp
+++ b/src/share/vm/opto/macro.cpp
@@ -2125,7 +2125,7 @@ void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
       Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
       klass_node = transform_later( LoadKlassNode::make(_igvn, mem, k_adr, _igvn.type(k_adr)->is_ptr()) );
 #ifdef _LP64
-      if (UseCompressedOops && klass_node->is_DecodeN()) {
+      if (UseCompressedKlassPointers && klass_node->is_DecodeNKlass()) {
         assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity");
         klass_node->in(1)->init_req(0, ctrl);
       } else
diff --git a/src/share/vm/opto/matcher.cpp b/src/share/vm/opto/matcher.cpp
index 8ee42d13d..53924d0c9 100644
--- a/src/share/vm/opto/matcher.cpp
+++ b/src/share/vm/opto/matcher.cpp
@@ -1058,7 +1058,7 @@ Node *Matcher::xform( Node *n, int max_stack ) {
         Node *m = n->in(i);          // Get input
         int op = m->Opcode();
         assert((op == Op_BoxLock) == jvms->is_monitor_use(i), "boxes only at monitor sites");
-        if( op == Op_ConI || op == Op_ConP || op == Op_ConN ||
+        if( op == Op_ConI || op == Op_ConP || op == Op_ConN || op == Op_ConNKlass ||
             op == Op_ConF || op == Op_ConD || op == Op_ConL
             // || op == Op_BoxLock  // %%%% enable this and remove (+++) in chaitin.cpp
             ) {
@@ -1450,7 +1450,8 @@ static bool match_into_reg( const Node *n, Node *m, Node *control, int i, bool s
       if (j == max_scan)        // No post-domination before scan end?
         return true;            // Then break the match tree up
     }
-    if (m->is_DecodeN() && Matcher::narrow_oop_use_complex_address()) {
+    if ((m->is_DecodeN() && Matcher::narrow_oop_use_complex_address()) ||
+        (m->is_DecodeNKlass() && Matcher::narrow_klass_use_complex_address())) {
       // These are commonly used in address expressions and can
       // efficiently fold into them on X64 in some cases.
       return false;
@@ -1574,14 +1575,14 @@ Node *Matcher::Label_Root( const Node *n, State *svec, Node *control, const Node
 // program.  The register allocator is free to split uses later to
 // split live ranges.
 MachNode* Matcher::find_shared_node(Node* leaf, uint rule) {
-  if (!leaf->is_Con() && !leaf->is_DecodeN()) return NULL;
+  if (!leaf->is_Con() && !leaf->is_DecodeNarrowPtr()) return NULL;
 
   // See if this Con has already been reduced using this rule.
   if (_shared_nodes.Size() <= leaf->_idx) return NULL;
   MachNode* last = (MachNode*)_shared_nodes.at(leaf->_idx);
   if (last != NULL && rule == last->rule()) {
     // Don't expect control change for DecodeN
-    if (leaf->is_DecodeN())
+    if (leaf->is_DecodeNarrowPtr())
       return last;
     // Get the new space root.
     Node* xroot = new_node(C->root());
@@ -1671,12 +1672,12 @@ MachNode *Matcher::ReduceInst( State *s, int rule, Node *&mem ) {
       // DecodeN node consumed by an address may have different type
       // then its input. Don't compare types for such case.
       if (m->adr_type() != mach_at &&
-          (m->in(MemNode::Address)->is_DecodeN() ||
+          (m->in(MemNode::Address)->is_DecodeNarrowPtr() ||
            m->in(MemNode::Address)->is_AddP() &&
-           m->in(MemNode::Address)->in(AddPNode::Address)->is_DecodeN() ||
+           m->in(MemNode::Address)->in(AddPNode::Address)->is_DecodeNarrowPtr() ||
            m->in(MemNode::Address)->is_AddP() &&
            m->in(MemNode::Address)->in(AddPNode::Address)->is_AddP() &&
-           m->in(MemNode::Address)->in(AddPNode::Address)->in(AddPNode::Address)->is_DecodeN())) {
+           m->in(MemNode::Address)->in(AddPNode::Address)->in(AddPNode::Address)->is_DecodeNarrowPtr())) {
         mach_at = m->adr_type();
       }
       if (m->adr_type() != mach_at) {
@@ -1721,7 +1722,7 @@ MachNode *Matcher::ReduceInst( State *s, int rule, Node *&mem ) {
     guarantee(_proj_list.size() == num_proj, "no allocation during spill generation");
   }
 
-  if (leaf->is_Con() || leaf->is_DecodeN()) {
+  if (leaf->is_Con() || leaf->is_DecodeNarrowPtr()) {
     // Record the con for sharing
     _shared_nodes.map(leaf->_idx, ex);
   }
@@ -2038,7 +2039,7 @@ void Matcher::find_shared( Node *n ) {
           continue; // for(int i = ...)
         }
 
-        if( mop == Op_AddP && m->in(AddPNode::Base)->Opcode() == Op_DecodeN ) {
+        if( mop == Op_AddP && m->in(AddPNode::Base)->is_DecodeNarrowPtr()) {
           // Bases used in addresses must be shared but since
           // they are shared through a DecodeN they may appear
           // to have a single use so force sharing here.
@@ -2277,7 +2278,7 @@ void Matcher::validate_null_checks( ) {
     if (has_new_node(val)) {
       Node* new_val = new_node(val);
       if (is_decoden) {
-        assert(val->is_DecodeN() && val->in(0) == NULL, "sanity");
+        assert(val->is_DecodeNarrowPtr() && val->in(0) == NULL, "sanity");
         // Note: new_val may have a control edge if
         // the original ideal node DecodeN was matched before
         // it was unpinned in Matcher::collect_null_checks().
diff --git a/src/share/vm/opto/matcher.hpp b/src/share/vm/opto/matcher.hpp
index 1936ba97a..280b8ad88 100644
--- a/src/share/vm/opto/matcher.hpp
+++ b/src/share/vm/opto/matcher.hpp
@@ -380,6 +380,7 @@ public:
   static const bool clone_shift_expressions;
 
   static bool narrow_oop_use_complex_address();
+  static bool narrow_klass_use_complex_address();
 
   // Generate implicit null check for narrow oops if it can fold
   // into address expression (x64).
diff --git a/src/share/vm/opto/memnode.cpp b/src/share/vm/opto/memnode.cpp
index 657d33105..30e3d2bbf 100644
--- a/src/share/vm/opto/memnode.cpp
+++ b/src/share/vm/opto/memnode.cpp
@@ -714,10 +714,12 @@ Node *MemNode::Ideal_common_DU_postCCP( PhaseCCP *ccp, Node* n, Node* adr ) {
         continue;
 
       case Op_DecodeN:         // No change to NULL-ness, so peek thru
+      case Op_DecodeNKlass:
         adr = adr->in(1);
         continue;
 
       case Op_EncodeP:
+      case Op_EncodePKlass:
         // EncodeP node's control edge could be set by this method
         // when EncodeP node depends on CastPP node.
         //
@@ -794,6 +796,7 @@ Node *MemNode::Ideal_common_DU_postCCP( PhaseCCP *ccp, Node* n, Node* adr ) {
       case Op_LoadNKlass:       // Loading from within a klass
       case Op_ConP:             // Loading from a klass
       case Op_ConN:             // Loading from a klass
+      case Op_ConNKlass:        // Loading from a klass
       case Op_CreateEx:         // Sucking up the guts of an exception oop
       case Op_Con:              // Reading from TLS
       case Op_CMoveP:           // CMoveP is pinned
@@ -900,7 +903,7 @@ Node *LoadNode::make( PhaseGVN& gvn, Node *ctl, Node *mem, Node *adr, const Type
     } else
 #endif
     {
-      assert(!adr->bottom_type()->is_ptr_to_narrowoop(), "should have got back a narrow oop");
+      assert(!adr->bottom_type()->is_ptr_to_narrowoop() && !adr->bottom_type()->is_ptr_to_narrowklass(), "should have got back a narrow oop");
       return new (C) LoadPNode(ctl, mem, adr, adr_type, rt->is_oopptr());
     }
   }
@@ -1894,13 +1897,13 @@ Node *LoadKlassNode::make( PhaseGVN& gvn, Node *mem, Node *adr, const TypePtr* a
   const TypePtr *adr_type = adr->bottom_type()->isa_ptr();
   assert(adr_type != NULL, "expecting TypeKlassPtr");
 #ifdef _LP64
-  if (adr_type->is_ptr_to_narrowoop()) {
+  if (adr_type->is_ptr_to_narrowklass()) {
     assert(UseCompressedKlassPointers, "no compressed klasses");
-    Node* load_klass = gvn.transform(new (C) LoadNKlassNode(ctl, mem, adr, at, tk->make_narrowoop()));
-    return new (C) DecodeNNode(load_klass, load_klass->bottom_type()->make_ptr());
+    Node* load_klass = gvn.transform(new (C) LoadNKlassNode(ctl, mem, adr, at, tk->make_narrowklass()));
+    return new (C) DecodeNKlassNode(load_klass, load_klass->bottom_type()->make_ptr());
   }
 #endif
-  assert(!adr_type->is_ptr_to_narrowoop(), "should have got back a narrow oop");
+  assert(!adr_type->is_ptr_to_narrowklass() && !adr_type->is_ptr_to_narrowoop(), "should have got back a narrow oop");
   return new (C) LoadKlassNode(ctl, mem, adr, at, tk);
 }
 
@@ -2110,7 +2113,7 @@ const Type *LoadNKlassNode::Value( PhaseTransform *phase ) const {
   if (t == Type::TOP)
     return t;
 
-  return t->make_narrowoop();
+  return t->make_narrowklass();
 }
 
 //------------------------------Identity---------------------------------------
@@ -2121,9 +2124,10 @@ Node* LoadNKlassNode::Identity( PhaseTransform *phase ) {
 
   const Type *t = phase->type( x );
   if( t == Type::TOP ) return x;
-  if( t->isa_narrowoop()) return x;
+  if( t->isa_narrowklass()) return x;
+  assert (!t->isa_narrowoop(), "no narrow oop here");
 
-  return phase->transform(new (phase->C) EncodePNode(x, t->make_narrowoop()));
+  return phase->transform(new (phase->C) EncodePKlassNode(x, t->make_narrowklass()));
 }
 
 //------------------------------Value-----------------------------------------
@@ -2228,12 +2232,15 @@ StoreNode* StoreNode::make( PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, cons
   case T_ADDRESS:
   case T_OBJECT:
 #ifdef _LP64
-    if (adr->bottom_type()->is_ptr_to_narrowoop() ||
-        (UseCompressedKlassPointers && val->bottom_type()->isa_klassptr() &&
-         adr->bottom_type()->isa_rawptr())) {
+    if (adr->bottom_type()->is_ptr_to_narrowoop()) {
       val = gvn.transform(new (C) EncodePNode(val, val->bottom_type()->make_narrowoop()));
       return new (C) StoreNNode(ctl, mem, adr, adr_type, val);
-    } else
+    } else if (adr->bottom_type()->is_ptr_to_narrowklass() ||
+               (UseCompressedKlassPointers && val->bottom_type()->isa_klassptr() &&
+                adr->bottom_type()->isa_rawptr())) {
+      val = gvn.transform(new (C) EncodePKlassNode(val, val->bottom_type()->make_narrowklass()));
+      return new (C) StoreNKlassNode(ctl, mem, adr, adr_type, val);
+    }
 #endif
     {
       return new (C) StorePNode(ctl, mem, adr, adr_type, val);
diff --git a/src/share/vm/opto/memnode.hpp b/src/share/vm/opto/memnode.hpp
index 6f722f938..8f0189570 100644
--- a/src/share/vm/opto/memnode.hpp
+++ b/src/share/vm/opto/memnode.hpp
@@ -437,12 +437,12 @@ public:
 // Load a narrow Klass from an object.
 class LoadNKlassNode : public LoadNNode {
 public:
-  LoadNKlassNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowOop *tk )
+  LoadNKlassNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk )
     : LoadNNode(c,mem,adr,at,tk) {}
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return Op_RegN; }
-  virtual int store_Opcode() const { return Op_StoreN; }
-  virtual BasicType memory_type() const { return T_NARROWOOP; }
+  virtual int store_Opcode() const { return Op_StoreNKlass; }
+  virtual BasicType memory_type() const { return T_NARROWKLASS; }
 
   virtual const Type *Value( PhaseTransform *phase ) const;
   virtual Node *Identity( PhaseTransform *phase );
@@ -593,6 +593,15 @@ public:
   virtual BasicType memory_type() const { return T_NARROWOOP; }
 };
 
+//------------------------------StoreNKlassNode--------------------------------------
+// Store narrow klass to memory
+class StoreNKlassNode : public StoreNNode {
+public:
+  StoreNKlassNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNNode(c,mem,adr,at,val) {}
+  virtual int Opcode() const;
+  virtual BasicType memory_type() const { return T_NARROWKLASS; }
+};
+
 //------------------------------StoreCMNode-----------------------------------
 // Store card-mark byte to memory for CM
 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
diff --git a/src/share/vm/opto/node.hpp b/src/share/vm/opto/node.hpp
index a6033c68b..f746f2e42 100644
--- a/src/share/vm/opto/node.hpp
+++ b/src/share/vm/opto/node.hpp
@@ -62,8 +62,12 @@ class ConstraintCastNode;
 class ConNode;
 class CountedLoopNode;
 class CountedLoopEndNode;
+class DecodeNarrowPtrNode;
 class DecodeNNode;
+class DecodeNKlassNode;
+class EncodeNarrowPtrNode;
 class EncodePNode;
+class EncodePKlassNode;
 class FastLockNode;
 class FastUnlockNode;
 class IfNode;
@@ -585,8 +589,12 @@ public:
       DEFINE_CLASS_ID(CheckCastPP, Type, 2)
       DEFINE_CLASS_ID(CMove, Type, 3)
       DEFINE_CLASS_ID(SafePointScalarObject, Type, 4)
-      DEFINE_CLASS_ID(DecodeN, Type, 5)
-      DEFINE_CLASS_ID(EncodeP, Type, 6)
+      DEFINE_CLASS_ID(DecodeNarrowPtr, Type, 5)
+        DEFINE_CLASS_ID(DecodeN, DecodeNarrowPtr, 0)
+        DEFINE_CLASS_ID(DecodeNKlass, DecodeNarrowPtr, 1)
+      DEFINE_CLASS_ID(EncodeNarrowPtr, Type, 6)
+        DEFINE_CLASS_ID(EncodeP, EncodeNarrowPtr, 0)
+        DEFINE_CLASS_ID(EncodePKlass, EncodeNarrowPtr, 1)
 
     DEFINE_CLASS_ID(Proj,  Node, 3)
       DEFINE_CLASS_ID(CatchProj, Proj, 0)
@@ -706,8 +714,12 @@ public:
   DEFINE_CLASS_QUERY(Cmp)
   DEFINE_CLASS_QUERY(CountedLoop)
   DEFINE_CLASS_QUERY(CountedLoopEnd)
+  DEFINE_CLASS_QUERY(DecodeNarrowPtr)
   DEFINE_CLASS_QUERY(DecodeN)
+  DEFINE_CLASS_QUERY(DecodeNKlass)
+  DEFINE_CLASS_QUERY(EncodeNarrowPtr)
   DEFINE_CLASS_QUERY(EncodeP)
+  DEFINE_CLASS_QUERY(EncodePKlass)
   DEFINE_CLASS_QUERY(FastLock)
   DEFINE_CLASS_QUERY(FastUnlock)
   DEFINE_CLASS_QUERY(If)
diff --git a/src/share/vm/opto/parse2.cpp b/src/share/vm/opto/parse2.cpp
index 0373ebfc9..af91156da 100644
--- a/src/share/vm/opto/parse2.cpp
+++ b/src/share/vm/opto/parse2.cpp
@@ -1239,7 +1239,7 @@ void Parse::adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
 
 static Node* extract_obj_from_klass_load(PhaseGVN* gvn, Node* n) {
   Node* ldk;
-  if (n->is_DecodeN()) {
+  if (n->is_DecodeNKlass()) {
     if (n->in(1)->Opcode() != Op_LoadNKlass) {
       return NULL;
     } else {
diff --git a/src/share/vm/opto/subnode.cpp b/src/share/vm/opto/subnode.cpp
index 81d698526..cbfe77751 100644
--- a/src/share/vm/opto/subnode.cpp
+++ b/src/share/vm/opto/subnode.cpp
@@ -789,7 +789,7 @@ Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
 
   // Now check for LoadKlass on left.
   Node* ldk1 = in(1);
-  if (ldk1->is_DecodeN()) {
+  if (ldk1->is_DecodeNKlass()) {
     ldk1 = ldk1->in(1);
     if (ldk1->Opcode() != Op_LoadNKlass )
       return NULL;
@@ -814,7 +814,7 @@ Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
 
   // Check for a LoadKlass from primary supertype array.
   // Any nested loadklass from loadklass+con must be from the p.s. array.
-  if (ldk2->is_DecodeN()) {
+  if (ldk2->is_DecodeNKlass()) {
     // Keep ldk2 as DecodeN since it could be used in CmpP below.
     if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
       return NULL;
diff --git a/src/share/vm/opto/type.cpp b/src/share/vm/opto/type.cpp
index 0a82b2f6a..f982799f6 100644
--- a/src/share/vm/opto/type.cpp
+++ b/src/share/vm/opto/type.cpp
@@ -57,6 +57,7 @@ Type::TypeInfo Type::_type_info[Type::lastype] = {
   { Bad,             T_LONG,       "long:",         false, Op_RegL,              relocInfo::none          },  // Long
   { Half,            T_VOID,       "half",          false, 0,                    relocInfo::none          },  // Half
   { Bad,             T_NARROWOOP,  "narrowoop:",    false, Op_RegN,              relocInfo::none          },  // NarrowOop
+  { Bad,             T_NARROWKLASS,"narrowklass:",  false, Op_RegN,              relocInfo::none          },  // NarrowKlass
   { Bad,             T_ILLEGAL,    "tuple:",        false, Node::NotAMachineReg, relocInfo::none          },  // Tuple
   { Bad,             T_ARRAY,      "array:",        false, Node::NotAMachineReg, relocInfo::none          },  // Array
 
@@ -332,6 +333,8 @@ void Type::Initialize_shared(Compile* current) {
   TypeNarrowOop::NULL_PTR = TypeNarrowOop::make( TypePtr::NULL_PTR );
   TypeNarrowOop::BOTTOM   = TypeNarrowOop::make( TypeInstPtr::BOTTOM );
 
+  TypeNarrowKlass::NULL_PTR = TypeNarrowKlass::make( TypePtr::NULL_PTR );
+
   mreg2type[Op_Node] = Type::BOTTOM;
   mreg2type[Op_Set ] = 0;
   mreg2type[Op_RegN] = TypeNarrowOop::BOTTOM;
@@ -395,34 +398,36 @@ void Type::Initialize_shared(Compile* current) {
   longpair[1] = TypeLong::LONG;
   TypeTuple::LONG_PAIR = TypeTuple::make(2, longpair);
 
-  _const_basic_type[T_NARROWOOP] = TypeNarrowOop::BOTTOM;
-  _const_basic_type[T_BOOLEAN] = TypeInt::BOOL;
-  _const_basic_type[T_CHAR]    = TypeInt::CHAR;
-  _const_basic_type[T_BYTE]    = TypeInt::BYTE;
-  _const_basic_type[T_SHORT]   = TypeInt::SHORT;
-  _const_basic_type[T_INT]     = TypeInt::INT;
-  _const_basic_type[T_LONG]    = TypeLong::LONG;
-  _const_basic_type[T_FLOAT]   = Type::FLOAT;
-  _const_basic_type[T_DOUBLE]  = Type::DOUBLE;
-  _const_basic_type[T_OBJECT]  = TypeInstPtr::BOTTOM;
-  _const_basic_type[T_ARRAY]   = TypeInstPtr::BOTTOM; // there is no separate bottom for arrays
-  _const_basic_type[T_VOID]    = TypePtr::NULL_PTR;   // reflection represents void this way
-  _const_basic_type[T_ADDRESS] = TypeRawPtr::BOTTOM;  // both interpreter return addresses & random raw ptrs
-  _const_basic_type[T_CONFLICT]= Type::BOTTOM;        // why not?
-
-  _zero_type[T_NARROWOOP] = TypeNarrowOop::NULL_PTR;
-  _zero_type[T_BOOLEAN] = TypeInt::ZERO;     // false == 0
-  _zero_type[T_CHAR]    = TypeInt::ZERO;     // '\0' == 0
-  _zero_type[T_BYTE]    = TypeInt::ZERO;     // 0x00 == 0
-  _zero_type[T_SHORT]   = TypeInt::ZERO;     // 0x0000 == 0
-  _zero_type[T_INT]     = TypeInt::ZERO;
-  _zero_type[T_LONG]    = TypeLong::ZERO;
-  _zero_type[T_FLOAT]   = TypeF::ZERO;
-  _zero_type[T_DOUBLE]  = TypeD::ZERO;
-  _zero_type[T_OBJECT]  = TypePtr::NULL_PTR;
-  _zero_type[T_ARRAY]   = TypePtr::NULL_PTR; // null array is null oop
-  _zero_type[T_ADDRESS] = TypePtr::NULL_PTR; // raw pointers use the same null
-  _zero_type[T_VOID]    = Type::TOP;         // the only void value is no value at all
+  _const_basic_type[T_NARROWOOP]   = TypeNarrowOop::BOTTOM;
+  _const_basic_type[T_NARROWKLASS] = Type::BOTTOM;
+  _const_basic_type[T_BOOLEAN]     = TypeInt::BOOL;
+  _const_basic_type[T_CHAR]        = TypeInt::CHAR;
+  _const_basic_type[T_BYTE]        = TypeInt::BYTE;
+  _const_basic_type[T_SHORT]       = TypeInt::SHORT;
+  _const_basic_type[T_INT]         = TypeInt::INT;
+  _const_basic_type[T_LONG]        = TypeLong::LONG;
+  _const_basic_type[T_FLOAT]       = Type::FLOAT;
+  _const_basic_type[T_DOUBLE]      = Type::DOUBLE;
+  _const_basic_type[T_OBJECT]      = TypeInstPtr::BOTTOM;
+  _const_basic_type[T_ARRAY]       = TypeInstPtr::BOTTOM; // there is no separate bottom for arrays
+  _const_basic_type[T_VOID]        = TypePtr::NULL_PTR;   // reflection represents void this way
+  _const_basic_type[T_ADDRESS]     = TypeRawPtr::BOTTOM;  // both interpreter return addresses & random raw ptrs
+  _const_basic_type[T_CONFLICT]    = Type::BOTTOM;        // why not?
+
+  _zero_type[T_NARROWOOP]   = TypeNarrowOop::NULL_PTR;
+  _zero_type[T_NARROWKLASS] = TypeNarrowKlass::NULL_PTR;
+  _zero_type[T_BOOLEAN]     = TypeInt::ZERO;     // false == 0
+  _zero_type[T_CHAR]        = TypeInt::ZERO;     // '\0' == 0
+  _zero_type[T_BYTE]        = TypeInt::ZERO;     // 0x00 == 0
+  _zero_type[T_SHORT]       = TypeInt::ZERO;     // 0x0000 == 0
+  _zero_type[T_INT]         = TypeInt::ZERO;
+  _zero_type[T_LONG]        = TypeLong::ZERO;
+  _zero_type[T_FLOAT]       = TypeF::ZERO;
+  _zero_type[T_DOUBLE]      = TypeD::ZERO;
+  _zero_type[T_OBJECT]      = TypePtr::NULL_PTR;
+  _zero_type[T_ARRAY]       = TypePtr::NULL_PTR; // null array is null oop
+  _zero_type[T_ADDRESS]     = TypePtr::NULL_PTR; // raw pointers use the same null
+  _zero_type[T_VOID]        = Type::TOP;         // the only void value is no value at all
 
   // get_zero_type() should not happen for T_CONFLICT
   _zero_type[T_CONFLICT]= NULL;
@@ -563,9 +568,14 @@ const Type *Type::meet( const Type *t ) const {
     const Type* result = make_ptr()->meet(t->make_ptr());
     return result->make_narrowoop();
   }
+  if (isa_narrowklass() && t->isa_narrowklass()) {
+    const Type* result = make_ptr()->meet(t->make_ptr());
+    return result->make_narrowklass();
+  }
 
   const Type *mt = xmeet(t);
   if (isa_narrowoop() || t->isa_narrowoop()) return mt;
+  if (isa_narrowklass() || t->isa_narrowklass()) return mt;
 #ifdef ASSERT
   assert( mt == t->xmeet(this), "meet not commutative" );
   const Type* dual_join = mt->_dual;
@@ -635,6 +645,9 @@ const Type *Type::xmeet( const Type *t ) const {
   case NarrowOop:
     return t->xmeet(this);
 
+  case NarrowKlass:
+    return t->xmeet(this);
+
   case Bad:                     // Type check
   default:                      // Bogus type not in lattice
     typerr(t);
@@ -693,6 +706,7 @@ const Type::TYPES Type::dual_type[Type::lastype] = {
   Bad,          // Long - handled in v-call
   Half,         // Half
   Bad,          // NarrowOop - handled in v-call
+  Bad,          // NarrowKlass - handled in v-call
 
   Bad,          // Tuple - handled in v-call
   Bad,          // Array - handled in v-call
@@ -756,6 +770,8 @@ void Type::dump_on(outputStream *st) const {
   dump2(d,1, st);
   if (is_ptr_to_narrowoop()) {
     st->print(" [narrow]");
+  } else if (is_ptr_to_narrowklass()) {
+    st->print(" [narrowklass]");
   }
 }
 #endif
@@ -838,6 +854,7 @@ const Type *TypeF::xmeet( const Type *t ) const {
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
+  case NarrowKlass:
   case Int:
   case Long:
   case DoubleTop:
@@ -955,6 +972,7 @@ const Type *TypeD::xmeet( const Type *t ) const {
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
+  case NarrowKlass:
   case Int:
   case Long:
   case FloatTop:
@@ -1109,6 +1127,7 @@ const Type *TypeInt::xmeet( const Type *t ) const {
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
+  case NarrowKlass:
   case Long:
   case FloatTop:
   case FloatCon:
@@ -1366,6 +1385,7 @@ const Type *TypeLong::xmeet( const Type *t ) const {
   case MetadataPtr:
   case KlassPtr:
   case NarrowOop:
+  case NarrowKlass:
   case Int:
   case FloatTop:
   case FloatCon:
@@ -2096,6 +2116,7 @@ const Type *TypePtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
@@ -2350,17 +2371,18 @@ TypeOopPtr::TypeOopPtr( TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int
     _const_oop(o), _klass(k),
     _klass_is_exact(xk),
     _is_ptr_to_narrowoop(false),
+    _is_ptr_to_narrowklass(false),
     _instance_id(instance_id) {
 #ifdef _LP64
-  if (UseCompressedOops && _offset != 0) {
+  if (_offset != 0) {
     if (_offset == oopDesc::klass_offset_in_bytes()) {
-      _is_ptr_to_narrowoop = UseCompressedKlassPointers;
+      _is_ptr_to_narrowklass = UseCompressedKlassPointers;
     } else if (klass() == NULL) {
       // Array with unknown body type
       assert(this->isa_aryptr(), "only arrays without klass");
-      _is_ptr_to_narrowoop = true;
+      _is_ptr_to_narrowoop = UseCompressedOops;
     } else if (this->isa_aryptr()) {
-      _is_ptr_to_narrowoop = (klass()->is_obj_array_klass() &&
+      _is_ptr_to_narrowoop = (UseCompressedOops && klass()->is_obj_array_klass() &&
                              _offset != arrayOopDesc::length_offset_in_bytes());
     } else if (klass()->is_instance_klass()) {
       ciInstanceKlass* ik = klass()->as_instance_klass();
@@ -2369,7 +2391,7 @@ TypeOopPtr::TypeOopPtr( TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int
         // Perm objects don't use compressed references
       } else if (_offset == OffsetBot || _offset == OffsetTop) {
         // unsafe access
-        _is_ptr_to_narrowoop = true;
+        _is_ptr_to_narrowoop = UseCompressedOops;
       } else { // exclude unsafe ops
         assert(this->isa_instptr(), "must be an instance ptr.");
 
@@ -2387,22 +2409,22 @@ TypeOopPtr::TypeOopPtr( TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int
           ciField* field = k->get_field_by_offset(_offset, true);
           assert(field != NULL, "missing field");
           BasicType basic_elem_type = field->layout_type();
-          _is_ptr_to_narrowoop = (basic_elem_type == T_OBJECT ||
-                                  basic_elem_type == T_ARRAY);
+          _is_ptr_to_narrowoop = UseCompressedOops && (basic_elem_type == T_OBJECT ||
+                                                       basic_elem_type == T_ARRAY);
         } else {
           // Instance fields which contains a compressed oop references.
           field = ik->get_field_by_offset(_offset, false);
           if (field != NULL) {
             BasicType basic_elem_type = field->layout_type();
-            _is_ptr_to_narrowoop = (basic_elem_type == T_OBJECT ||
-                                    basic_elem_type == T_ARRAY);
+            _is_ptr_to_narrowoop = UseCompressedOops && (basic_elem_type == T_OBJECT ||
+                                                         basic_elem_type == T_ARRAY);
           } else if (klass()->equals(ciEnv::current()->Object_klass())) {
             // Compile::find_alias_type() cast exactness on all types to verify
             // that it does not affect alias type.
-            _is_ptr_to_narrowoop = true;
+            _is_ptr_to_narrowoop = UseCompressedOops;
           } else {
             // Type for the copy start in LibraryCallKit::inline_native_clone().
-            _is_ptr_to_narrowoop = true;
+            _is_ptr_to_narrowoop = UseCompressedOops;
           }
         }
       }
@@ -2475,6 +2497,7 @@ const Type *TypeOopPtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
@@ -2925,6 +2948,7 @@ const Type *TypeInstPtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
@@ -3353,6 +3377,7 @@ static jint max_array_length(BasicType etype) {
     case T_NARROWOOP:
       etype = T_OBJECT;
       break;
+    case T_NARROWKLASS:
     case T_CONFLICT:
     case T_ILLEGAL:
     case T_VOID:
@@ -3425,6 +3450,7 @@ const Type *TypeAryPtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
@@ -3671,23 +3697,27 @@ const TypePtr *TypeAryPtr::add_offset( intptr_t offset ) const {
 
 
 //=============================================================================
-const TypeNarrowOop *TypeNarrowOop::BOTTOM;
-const TypeNarrowOop *TypeNarrowOop::NULL_PTR;
-
-
-const TypeNarrowOop* TypeNarrowOop::make(const TypePtr* type) {
-  return (const TypeNarrowOop*)(new TypeNarrowOop(type))->hashcons();
-}
 
 //------------------------------hash-------------------------------------------
 // Type-specific hashing function.
-int TypeNarrowOop::hash(void) const {
+int TypeNarrowPtr::hash(void) const {
   return _ptrtype->hash() + 7;
 }
 
+bool TypeNarrowPtr::singleton(void) const {    // TRUE if type is a singleton
+  return _ptrtype->singleton();
+}
+
+bool TypeNarrowPtr::empty(void) const {
+  return _ptrtype->empty();
+}
+
+intptr_t TypeNarrowPtr::get_con() const {
+  return _ptrtype->get_con();
+}
 
-bool TypeNarrowOop::eq( const Type *t ) const {
-  const TypeNarrowOop* tc = t->isa_narrowoop();
+bool TypeNarrowPtr::eq( const Type *t ) const {
+  const TypeNarrowPtr* tc = isa_same_narrowptr(t);
   if (tc != NULL) {
     if (_ptrtype->base() != tc->_ptrtype->base()) {
       return false;
@@ -3697,22 +3727,46 @@ bool TypeNarrowOop::eq( const Type *t ) const {
   return false;
 }
 
-bool TypeNarrowOop::singleton(void) const {    // TRUE if type is a singleton
-  return _ptrtype->singleton();
+const Type *TypeNarrowPtr::xdual() const {    // Compute dual right now.
+  const TypePtr* odual = _ptrtype->dual()->is_ptr();
+  return make_same_narrowptr(odual);
 }
 
-bool TypeNarrowOop::empty(void) const {
-  return _ptrtype->empty();
+
+const Type *TypeNarrowPtr::filter( const Type *kills ) const {
+  if (isa_same_narrowptr(kills)) {
+    const Type* ft =_ptrtype->filter(is_same_narrowptr(kills)->_ptrtype);
+    if (ft->empty())
+      return Type::TOP;           // Canonical empty value
+    if (ft->isa_ptr()) {
+      return make_hash_same_narrowptr(ft->isa_ptr());
+    }
+    return ft;
+  } else if (kills->isa_ptr()) {
+    const Type* ft = _ptrtype->join(kills);
+    if (ft->empty())
+      return Type::TOP;           // Canonical empty value
+    return ft;
+  } else {
+    return Type::TOP;
+  }
 }
 
 //------------------------------xmeet------------------------------------------
 // Compute the MEET of two types.  It returns a new Type object.
-const Type *TypeNarrowOop::xmeet( const Type *t ) const {
+const Type *TypeNarrowPtr::xmeet( const Type *t ) const {
   // Perform a fast test for common case; meeting the same types together.
   if( this == t ) return this;  // Meeting same type-rep?
 
+  if (t->base() == base()) {
+    const Type* result = _ptrtype->xmeet(t->make_ptr());
+    if (result->isa_ptr()) {
+      return make_hash_same_narrowptr(result->is_ptr());
+    }
+    return result;
+  }
 
-  // Current "this->_base" is OopPtr
+  // Current "this->_base" is NarrowKlass or NarrowOop
   switch (t->base()) {          // switch on original type
 
   case Int:                     // Mixing ints & oops happens when javac
@@ -3730,20 +3784,14 @@ const Type *TypeNarrowOop::xmeet( const Type *t ) const {
   case AryPtr:
   case MetadataPtr:
   case KlassPtr:
+  case NarrowOop:
+  case NarrowKlass:
 
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
     return this;
 
-  case NarrowOop: {
-    const Type* result = _ptrtype->xmeet(t->make_ptr());
-    if (result->isa_ptr()) {
-      return TypeNarrowOop::make(result->is_ptr());
-    }
-    return result;
-  }
-
   default:                      // All else is a mistake
     typerr(t);
 
@@ -3752,42 +3800,40 @@ const Type *TypeNarrowOop::xmeet( const Type *t ) const {
   return this;
 }
 
-const Type *TypeNarrowOop::xdual() const {    // Compute dual right now.
-  const TypePtr* odual = _ptrtype->dual()->is_ptr();
-  return new TypeNarrowOop(odual);
+#ifndef PRODUCT
+void TypeNarrowPtr::dump2( Dict & d, uint depth, outputStream *st ) const {
+  _ptrtype->dump2(d, depth, st);
 }
+#endif
 
-const Type *TypeNarrowOop::filter( const Type *kills ) const {
-  if (kills->isa_narrowoop()) {
-    const Type* ft =_ptrtype->filter(kills->is_narrowoop()->_ptrtype);
-    if (ft->empty())
-      return Type::TOP;           // Canonical empty value
-    if (ft->isa_ptr()) {
-      return make(ft->isa_ptr());
-    }
-    return ft;
-  } else if (kills->isa_ptr()) {
-    const Type* ft = _ptrtype->join(kills);
-    if (ft->empty())
-      return Type::TOP;           // Canonical empty value
-    return ft;
-  } else {
-    return Type::TOP;
-  }
-}
+const TypeNarrowOop *TypeNarrowOop::BOTTOM;
+const TypeNarrowOop *TypeNarrowOop::NULL_PTR;
 
 
-intptr_t TypeNarrowOop::get_con() const {
-  return _ptrtype->get_con();
+const TypeNarrowOop* TypeNarrowOop::make(const TypePtr* type) {
+  return (const TypeNarrowOop*)(new TypeNarrowOop(type))->hashcons();
 }
 
+
 #ifndef PRODUCT
 void TypeNarrowOop::dump2( Dict & d, uint depth, outputStream *st ) const {
   st->print("narrowoop: ");
-  _ptrtype->dump2(d, depth, st);
+  TypeNarrowPtr::dump2(d, depth, st);
 }
 #endif
 
+const TypeNarrowKlass *TypeNarrowKlass::NULL_PTR;
+
+const TypeNarrowKlass* TypeNarrowKlass::make(const TypePtr* type) {
+  return (const TypeNarrowKlass*)(new TypeNarrowKlass(type))->hashcons();
+}
+
+#ifndef PRODUCT
+void TypeNarrowKlass::dump2( Dict & d, uint depth, outputStream *st ) const {
+  st->print("narrowklass: ");
+  TypeNarrowPtr::dump2(d, depth, st);
+}
+#endif
 
 
 //------------------------------eq---------------------------------------------
@@ -3878,6 +3924,7 @@ const Type *TypeMetadataPtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
@@ -4169,6 +4216,7 @@ const Type    *TypeKlassPtr::xmeet( const Type *t ) const {
   case DoubleCon:
   case DoubleBot:
   case NarrowOop:
+  case NarrowKlass:
   case Bottom:                  // Ye Olde Default
     return Type::BOTTOM;
   case Top:
diff --git a/src/share/vm/opto/type.hpp b/src/share/vm/opto/type.hpp
index 666c78f5c..39bbf0306 100644
--- a/src/share/vm/opto/type.hpp
+++ b/src/share/vm/opto/type.hpp
@@ -48,7 +48,9 @@ class   TypeD;
 class   TypeF;
 class   TypeInt;
 class   TypeLong;
-class   TypeNarrowOop;
+class   TypeNarrowPtr;
+class     TypeNarrowOop;
+class     TypeNarrowKlass;
 class   TypeAry;
 class   TypeTuple;
 class   TypeVect;
@@ -81,6 +83,7 @@ public:
     Long,                       // Long integer range (lo-hi)
     Half,                       // Placeholder half of doubleword
     NarrowOop,                  // Compressed oop pointer
+    NarrowKlass,                // Compressed klass pointer
 
     Tuple,                      // Method signature or object layout
     Array,                      // Array types
@@ -229,6 +232,7 @@ public:
   // Returns true if this pointer points at memory which contains a
   // compressed oop references.
   bool is_ptr_to_narrowoop() const;
+  bool is_ptr_to_narrowklass() const;
 
   // Convenience access
   float getf() const;
@@ -252,6 +256,8 @@ public:
   const TypeRawPtr *is_rawptr() const;           // Asserts is rawptr
   const TypeNarrowOop  *is_narrowoop() const;    // Java-style GC'd pointer
   const TypeNarrowOop  *isa_narrowoop() const;   // Returns NULL if not oop ptr type
+  const TypeNarrowKlass *is_narrowklass() const; // compressed klass pointer
+  const TypeNarrowKlass *isa_narrowklass() const;// Returns NULL if not oop ptr type
   const TypeOopPtr   *isa_oopptr() const;        // Returns NULL if not oop ptr type
   const TypeOopPtr   *is_oopptr() const;         // Java-style GC'd pointer
   const TypeInstPtr  *isa_instptr() const;       // Returns NULL if not InstPtr
@@ -278,6 +284,10 @@ public:
   // of this pointer type.
   const TypeNarrowOop* make_narrowoop() const;
 
+  // Returns this compressed klass pointer or the equivalent
+  // compressed version of this pointer type.
+  const TypeNarrowKlass* make_narrowklass() const;
+
   // Special test for register pressure heuristic
   bool is_floatingpoint() const;        // True if Float or Double base type
 
@@ -670,7 +680,7 @@ class TypeVectY : public TypeVect {
 // Otherwise the _base will indicate which subset of pointers is affected,
 // and the class will be inherited from.
 class TypePtr : public Type {
-  friend class TypeNarrowOop;
+  friend class TypeNarrowPtr;
 public:
   enum PTR { TopPTR, AnyNull, Constant, Null, NotNull, BotPTR, lastPTR };
 protected:
@@ -781,6 +791,7 @@ protected:
   // Does the type exclude subclasses of the klass?  (Inexact == polymorphic.)
   bool          _klass_is_exact;
   bool          _is_ptr_to_narrowoop;
+  bool          _is_ptr_to_narrowklass;
 
   // If not InstanceTop or InstanceBot, indicates that this is
   // a particular instance of this type which is distinct.
@@ -825,6 +836,7 @@ public:
   // Returns true if this pointer points at memory which contains a
   // compressed oop references.
   bool is_ptr_to_narrowoop_nv() const { return _is_ptr_to_narrowoop; }
+  bool is_ptr_to_narrowklass_nv() const { return _is_ptr_to_narrowklass; }
 
   bool is_known_instance()       const { return _instance_id > 0; }
   int  instance_id()             const { return _instance_id; }
@@ -1122,22 +1134,21 @@ public:
 #endif
 };
 
-//------------------------------TypeNarrowOop----------------------------------
-// A compressed reference to some kind of Oop.  This type wraps around
-// a preexisting TypeOopPtr and forwards most of it's operations to
-// the underlying type.  It's only real purpose is to track the
-// oopness of the compressed oop value when we expose the conversion
-// between the normal and the compressed form.
-class TypeNarrowOop : public Type {
+class TypeNarrowPtr : public Type {
 protected:
   const TypePtr* _ptrtype; // Could be TypePtr::NULL_PTR
 
-  TypeNarrowOop( const TypePtr* ptrtype): Type(NarrowOop),
-    _ptrtype(ptrtype) {
+  TypeNarrowPtr(TYPES t, const TypePtr* ptrtype): _ptrtype(ptrtype),
+                                                  Type(t) {
     assert(ptrtype->offset() == 0 ||
            ptrtype->offset() == OffsetBot ||
            ptrtype->offset() == OffsetTop, "no real offsets");
   }
+
+  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const = 0;
+  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const = 0;
+  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const = 0;
+  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const = 0;
 public:
   virtual bool eq( const Type *t ) const;
   virtual int  hash() const;             // Type specific hashing
@@ -1153,17 +1164,51 @@ public:
 
   virtual bool empty(void) const;        // TRUE if type is vacuous
 
+  // returns the equivalent ptr type for this compressed pointer
+  const TypePtr *get_ptrtype() const {
+    return _ptrtype;
+  }
+
+#ifndef PRODUCT
+  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
+#endif
+};
+
+//------------------------------TypeNarrowOop----------------------------------
+// A compressed reference to some kind of Oop.  This type wraps around
+// a preexisting TypeOopPtr and forwards most of it's operations to
+// the underlying type.  It's only real purpose is to track the
+// oopness of the compressed oop value when we expose the conversion
+// between the normal and the compressed form.
+class TypeNarrowOop : public TypeNarrowPtr {
+protected:
+  TypeNarrowOop( const TypePtr* ptrtype): TypeNarrowPtr(NarrowOop, ptrtype) {
+  }
+
+  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const {
+    return t->isa_narrowoop();
+  }
+
+  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const {
+    return t->is_narrowoop();
+  }
+
+  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const {
+    return new TypeNarrowOop(t);
+  }
+
+  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const {
+    return (const TypeNarrowPtr*)((new TypeNarrowOop(t))->hashcons());
+  }
+
+public:
+
   static const TypeNarrowOop *make( const TypePtr* type);
 
   static const TypeNarrowOop* make_from_constant(ciObject* con, bool require_constant = false) {
     return make(TypeOopPtr::make_from_constant(con, require_constant));
   }
 
-  // returns the equivalent ptr type for this compressed pointer
-  const TypePtr *get_ptrtype() const {
-    return _ptrtype;
-  }
-
   static const TypeNarrowOop *BOTTOM;
   static const TypeNarrowOop *NULL_PTR;
 
@@ -1172,6 +1217,42 @@ public:
 #endif
 };
 
+//------------------------------TypeNarrowKlass----------------------------------
+// A compressed reference to klass pointer.  This type wraps around a
+// preexisting TypeKlassPtr and forwards most of it's operations to
+// the underlying type.
+class TypeNarrowKlass : public TypeNarrowPtr {
+protected:
+  TypeNarrowKlass( const TypePtr* ptrtype): TypeNarrowPtr(NarrowKlass, ptrtype) {
+  }
+
+  virtual const TypeNarrowPtr *isa_same_narrowptr(const Type *t) const {
+    return t->isa_narrowklass();
+  }
+
+  virtual const TypeNarrowPtr *is_same_narrowptr(const Type *t) const {
+    return t->is_narrowklass();
+  }
+
+  virtual const TypeNarrowPtr *make_same_narrowptr(const TypePtr *t) const {
+    return new TypeNarrowKlass(t);
+  }
+
+  virtual const TypeNarrowPtr *make_hash_same_narrowptr(const TypePtr *t) const {
+    return (const TypeNarrowPtr*)((new TypeNarrowKlass(t))->hashcons());
+  }
+
+public:
+  static const TypeNarrowKlass *make( const TypePtr* type);
+
+  // static const TypeNarrowKlass *BOTTOM;
+  static const TypeNarrowKlass *NULL_PTR;
+
+#ifndef PRODUCT
+  virtual void dump2( Dict &d, uint depth, outputStream *st ) const;
+#endif
+};
+
 //------------------------------TypeFunc---------------------------------------
 // Class of Array Types
 class TypeFunc : public Type {
@@ -1221,6 +1302,14 @@ inline bool Type::is_ptr_to_narrowoop() const {
 #endif
 }
 
+inline bool Type::is_ptr_to_narrowklass() const {
+#ifdef _LP64
+  return (isa_oopptr() != NULL && is_oopptr()->is_ptr_to_narrowklass_nv());
+#else
+  return false;
+#endif
+}
+
 inline float Type::getf() const {
   assert( _base == FloatCon, "Not a FloatCon" );
   return ((TypeF*)this)->_f;
@@ -1346,6 +1435,15 @@ inline const TypeNarrowOop *Type::isa_narrowoop() const {
   return (_base == NarrowOop) ? (TypeNarrowOop*)this : NULL;
 }
 
+inline const TypeNarrowKlass *Type::is_narrowklass() const {
+  assert(_base == NarrowKlass, "Not a narrow oop" ) ;
+  return (TypeNarrowKlass*)this;
+}
+
+inline const TypeNarrowKlass *Type::isa_narrowklass() const {
+  return (_base == NarrowKlass) ? (TypeNarrowKlass*)this : NULL;
+}
+
 inline const TypeMetadataPtr *Type::is_metadataptr() const {
   // MetadataPtr is the first and CPCachePtr the last
   assert(_base == MetadataPtr, "Not a metadata pointer" ) ;
@@ -1367,7 +1465,8 @@ inline const TypeKlassPtr *Type::is_klassptr() const {
 
 inline const TypePtr* Type::make_ptr() const {
   return (_base == NarrowOop) ? is_narrowoop()->get_ptrtype() :
-                                (isa_ptr() ? is_ptr() : NULL);
+    ((_base == NarrowKlass) ? is_narrowklass()->get_ptrtype() :
+     (isa_ptr() ? is_ptr() : NULL));
 }
 
 inline const TypeOopPtr* Type::make_oopptr() const {
@@ -1379,6 +1478,11 @@ inline const TypeNarrowOop* Type::make_narrowoop() const {
                                 (isa_ptr() ? TypeNarrowOop::make(is_ptr()) : NULL);
 }
 
+inline const TypeNarrowKlass* Type::make_narrowklass() const {
+  return (_base == NarrowKlass) ? is_narrowklass() :
+                                (isa_ptr() ? TypeNarrowKlass::make(is_ptr()) : NULL);
+}
+
 inline bool Type::is_floatingpoint() const {
   if( (_base == FloatCon)  || (_base == FloatBot) ||
       (_base == DoubleCon) || (_base == DoubleBot) )
diff --git a/src/share/vm/runtime/arguments.cpp b/src/share/vm/runtime/arguments.cpp
index f514f02c5..e0b4f9332 100644
--- a/src/share/vm/runtime/arguments.cpp
+++ b/src/share/vm/runtime/arguments.cpp
@@ -1423,10 +1423,9 @@ void Arguments::set_ergonomics_flags() {
     FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
   } else {
     // Turn on UseCompressedKlassPointers too
-    // The compiler is broken for this so turn it on when the compiler is fixed.
-    // if (FLAG_IS_DEFAULT(UseCompressedKlassPointers)) {
-    //   FLAG_SET_ERGO(bool, UseCompressedKlassPointers, true);
-    // }
+    if (FLAG_IS_DEFAULT(UseCompressedKlassPointers)) {
+      FLAG_SET_ERGO(bool, UseCompressedKlassPointers, true);
+    }
     // Set the ClassMetaspaceSize to something that will not need to be
     // expanded, since it cannot be expanded.
     if (UseCompressedKlassPointers && FLAG_IS_DEFAULT(ClassMetaspaceSize)) {
diff --git a/src/share/vm/runtime/stubRoutines.cpp b/src/share/vm/runtime/stubRoutines.cpp
index 4900eaeaf..071a3471a 100644
--- a/src/share/vm/runtime/stubRoutines.cpp
+++ b/src/share/vm/runtime/stubRoutines.cpp
@@ -421,6 +421,7 @@ address StubRoutines::select_fill_function(BasicType t, bool aligned, const char
   case T_ARRAY:
   case T_OBJECT:
   case T_NARROWOOP:
+  case T_NARROWKLASS:
   case T_ADDRESS:
     // Currently unsupported
     return NULL;
diff --git a/src/share/vm/runtime/vmStructs.cpp b/src/share/vm/runtime/vmStructs.cpp
index bc0435a57..a20ec675b 100644
--- a/src/share/vm/runtime/vmStructs.cpp
+++ b/src/share/vm/runtime/vmStructs.cpp
@@ -454,6 +454,8 @@ typedef TwoOopHashtable<Symbol*, mtClass>     SymbolTwoOopHashtable;
      static_field(Universe,                    _narrow_oop._base,                             address)                               \
      static_field(Universe,                    _narrow_oop._shift,                            int)                                   \
      static_field(Universe,                    _narrow_oop._use_implicit_null_checks,         bool)                                  \
+     static_field(Universe,                    _narrow_klass._base,                           address)                               \
+     static_field(Universe,                    _narrow_klass._shift,                          int)                                   \
                                                                                                                                      \
   /**********************************************************************************/                                               \
   /* Generation and Space hierarchies                                               */                                               \
@@ -1727,6 +1729,8 @@ typedef TwoOopHashtable<Symbol*, mtClass>     SymbolTwoOopHashtable;
   declare_c2_type(CMoveNNode, CMoveNode)                                  \
   declare_c2_type(EncodePNode, TypeNode)                                  \
   declare_c2_type(DecodeNNode, TypeNode)                                  \
+  declare_c2_type(EncodePKlassNode, TypeNode)                             \
+  declare_c2_type(DecodeNKlassNode, TypeNode)                             \
   declare_c2_type(ConstraintCastNode, TypeNode)                           \
   declare_c2_type(CastIINode, ConstraintCastNode)                         \
   declare_c2_type(CastPPNode, ConstraintCastNode)                         \
@@ -1823,6 +1827,7 @@ typedef TwoOopHashtable<Symbol*, mtClass>     SymbolTwoOopHashtable;
   declare_c2_type(StoreDNode, StoreNode)                                  \
   declare_c2_type(StorePNode, StoreNode)                                  \
   declare_c2_type(StoreNNode, StoreNode)                                  \
+  declare_c2_type(StoreNKlassNode, StoreNode)                             \
   declare_c2_type(StoreCMNode, StoreNode)                                 \
   declare_c2_type(LoadPLockedNode, LoadPNode)                             \
   declare_c2_type(SCMemProjNode, ProjNode)                                \
diff --git a/src/share/vm/utilities/globalDefinitions.cpp b/src/share/vm/utilities/globalDefinitions.cpp
index cfec229ee..778fd500e 100644
--- a/src/share/vm/utilities/globalDefinitions.cpp
+++ b/src/share/vm/utilities/globalDefinitions.cpp
@@ -111,11 +111,12 @@ void basic_types_init() {
       case T_DOUBLE:
       case T_LONG:
       case T_OBJECT:
-      case T_ADDRESS:   // random raw pointer
-      case T_METADATA:  // metadata pointer
-      case T_NARROWOOP: // compressed pointer
-      case T_CONFLICT:  // might as well support a bottom type
-      case T_VOID:      // padding or other unaddressed word
+      case T_ADDRESS:     // random raw pointer
+      case T_METADATA:    // metadata pointer
+      case T_NARROWOOP:   // compressed pointer
+      case T_NARROWKLASS: // compressed klass pointer
+      case T_CONFLICT:    // might as well support a bottom type
+      case T_VOID:        // padding or other unaddressed word
         // layout type must map to itself
         assert(vt == ft, "");
         break;
@@ -179,7 +180,7 @@ void basic_types_init() {
 
 
 // Map BasicType to signature character
-char type2char_tab[T_CONFLICT+1]={ 0, 0, 0, 0, 'Z', 'C', 'F', 'D', 'B', 'S', 'I', 'J', 'L', '[', 'V', 0, 0, 0, 0};
+char type2char_tab[T_CONFLICT+1]={ 0, 0, 0, 0, 'Z', 'C', 'F', 'D', 'B', 'S', 'I', 'J', 'L', '[', 'V', 0, 0, 0, 0, 0};
 
 // Map BasicType to Java type name
 const char* type2name_tab[T_CONFLICT+1] = {
@@ -198,6 +199,7 @@ const char* type2name_tab[T_CONFLICT+1] = {
   "*address*",
   "*narrowoop*",
   "*metadata*",
+  "*narrowklass*",
   "*conflict*"
 };
 
@@ -213,7 +215,7 @@ BasicType name2type(const char* name) {
 
 
 // Map BasicType to size in words
-int type2size[T_CONFLICT+1]={ -1, 0, 0, 0, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 0, 1, 1, 1, -1};
+int type2size[T_CONFLICT+1]={ -1, 0, 0, 0, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 0, 1, 1, 1, 1, -1};
 
 BasicType type2field[T_CONFLICT+1] = {
   (BasicType)0,            // 0,
@@ -234,7 +236,8 @@ BasicType type2field[T_CONFLICT+1] = {
   T_ADDRESS,               // T_ADDRESS  = 15,
   T_NARROWOOP,             // T_NARROWOOP= 16,
   T_METADATA,              // T_METADATA = 17,
-  T_CONFLICT               // T_CONFLICT = 18,
+  T_NARROWKLASS,           // T_NARROWKLASS = 18,
+  T_CONFLICT               // T_CONFLICT = 19,
 };
 
 
@@ -257,30 +260,32 @@ BasicType type2wfield[T_CONFLICT+1] = {
   T_ADDRESS, // T_ADDRESS  = 15,
   T_NARROWOOP, // T_NARROWOOP  = 16,
   T_METADATA,  // T_METADATA   = 17,
-  T_CONFLICT // T_CONFLICT = 18,
+  T_NARROWKLASS, // T_NARROWKLASS  = 18,
+  T_CONFLICT // T_CONFLICT = 19,
 };
 
 
 int _type2aelembytes[T_CONFLICT+1] = {
-  0,                      // 0
-  0,                      // 1
-  0,                      // 2
-  0,                      // 3
-  T_BOOLEAN_aelem_bytes,  // T_BOOLEAN  =  4,
-  T_CHAR_aelem_bytes,     // T_CHAR     =  5,
-  T_FLOAT_aelem_bytes,    // T_FLOAT    =  6,
-  T_DOUBLE_aelem_bytes,   // T_DOUBLE   =  7,
-  T_BYTE_aelem_bytes,     // T_BYTE     =  8,
-  T_SHORT_aelem_bytes,    // T_SHORT    =  9,
-  T_INT_aelem_bytes,      // T_INT      = 10,
-  T_LONG_aelem_bytes,     // T_LONG     = 11,
-  T_OBJECT_aelem_bytes,   // T_OBJECT   = 12,
-  T_ARRAY_aelem_bytes,    // T_ARRAY    = 13,
-  0,                      // T_VOID     = 14,
-  T_OBJECT_aelem_bytes,   // T_ADDRESS  = 15,
-  T_NARROWOOP_aelem_bytes,// T_NARROWOOP= 16,
-  T_OBJECT_aelem_bytes,   // T_METADATA = 17,
-  0                       // T_CONFLICT = 18,
+  0,                         // 0
+  0,                         // 1
+  0,                         // 2
+  0,                         // 3
+  T_BOOLEAN_aelem_bytes,     // T_BOOLEAN  =  4,
+  T_CHAR_aelem_bytes,        // T_CHAR     =  5,
+  T_FLOAT_aelem_bytes,       // T_FLOAT    =  6,
+  T_DOUBLE_aelem_bytes,      // T_DOUBLE   =  7,
+  T_BYTE_aelem_bytes,        // T_BYTE     =  8,
+  T_SHORT_aelem_bytes,       // T_SHORT    =  9,
+  T_INT_aelem_bytes,         // T_INT      = 10,
+  T_LONG_aelem_bytes,        // T_LONG     = 11,
+  T_OBJECT_aelem_bytes,      // T_OBJECT   = 12,
+  T_ARRAY_aelem_bytes,       // T_ARRAY    = 13,
+  0,                         // T_VOID     = 14,
+  T_OBJECT_aelem_bytes,      // T_ADDRESS  = 15,
+  T_NARROWOOP_aelem_bytes,   // T_NARROWOOP= 16,
+  T_OBJECT_aelem_bytes,      // T_METADATA = 17,
+  T_NARROWKLASS_aelem_bytes, // T_NARROWKLASS= 18,
+  0                          // T_CONFLICT = 19,
 };
 
 #ifdef ASSERT
diff --git a/src/share/vm/utilities/globalDefinitions.hpp b/src/share/vm/utilities/globalDefinitions.hpp
index 9909dd8eb..0c8ad4af8 100644
--- a/src/share/vm/utilities/globalDefinitions.hpp
+++ b/src/share/vm/utilities/globalDefinitions.hpp
@@ -347,6 +347,14 @@ extern int MinObjAlignmentInBytesMask;
 extern int LogMinObjAlignment;
 extern int LogMinObjAlignmentInBytes;
 
+const int LogKlassAlignmentInBytes = 3;
+const int LogKlassAlignment        = LogKlassAlignmentInBytes - LogHeapWordSize;
+const int KlassAlignmentInBytes    = 1 << LogKlassAlignmentInBytes;
+const int KlassAlignment           = KlassAlignmentInBytes / HeapWordSize;
+
+// Klass encoding metaspace max size
+const uint64_t KlassEncodingMetaspaceMax = (uint64_t(max_juint) + 1) << LogKlassAlignmentInBytes;
+
 // Machine dependent stuff
 
 #ifdef TARGET_ARCH_x86
@@ -481,22 +489,23 @@ void basic_types_init(); // cannot define here; uses assert
 
 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 enum BasicType {
-  T_BOOLEAN  =  4,
-  T_CHAR     =  5,
-  T_FLOAT    =  6,
-  T_DOUBLE   =  7,
-  T_BYTE     =  8,
-  T_SHORT    =  9,
-  T_INT      = 10,
-  T_LONG     = 11,
-  T_OBJECT   = 12,
-  T_ARRAY    = 13,
-  T_VOID     = 14,
-  T_ADDRESS  = 15,
-  T_NARROWOOP= 16,
-  T_METADATA = 17,
-  T_CONFLICT = 18, // for stack value type with conflicting contents
-  T_ILLEGAL  = 99
+  T_BOOLEAN     =  4,
+  T_CHAR        =  5,
+  T_FLOAT       =  6,
+  T_DOUBLE      =  7,
+  T_BYTE        =  8,
+  T_SHORT       =  9,
+  T_INT         = 10,
+  T_LONG        = 11,
+  T_OBJECT      = 12,
+  T_ARRAY       = 13,
+  T_VOID        = 14,
+  T_ADDRESS     = 15,
+  T_NARROWOOP   = 16,
+  T_METADATA    = 17,
+  T_NARROWKLASS = 18,
+  T_CONFLICT    = 19, // for stack value type with conflicting contents
+  T_ILLEGAL     = 99
 };
 
 inline bool is_java_primitive(BasicType t) {
@@ -544,18 +553,19 @@ extern size_t lcm(size_t a, size_t b);
 
 // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/runtime/BasicType.java
 enum BasicTypeSize {
-  T_BOOLEAN_size = 1,
-  T_CHAR_size    = 1,
-  T_FLOAT_size   = 1,
-  T_DOUBLE_size  = 2,
-  T_BYTE_size    = 1,
-  T_SHORT_size   = 1,
-  T_INT_size     = 1,
-  T_LONG_size    = 2,
-  T_OBJECT_size  = 1,
-  T_ARRAY_size   = 1,
-  T_NARROWOOP_size = 1,
-  T_VOID_size    = 0
+  T_BOOLEAN_size     = 1,
+  T_CHAR_size        = 1,
+  T_FLOAT_size       = 1,
+  T_DOUBLE_size      = 2,
+  T_BYTE_size        = 1,
+  T_SHORT_size       = 1,
+  T_INT_size         = 1,
+  T_LONG_size        = 2,
+  T_OBJECT_size      = 1,
+  T_ARRAY_size       = 1,
+  T_NARROWOOP_size   = 1,
+  T_NARROWKLASS_size = 1,
+  T_VOID_size        = 0
 };
 
 
@@ -567,23 +577,24 @@ extern BasicType type2wfield[T_CONFLICT+1];
 
 // size in bytes
 enum ArrayElementSize {
-  T_BOOLEAN_aelem_bytes = 1,
-  T_CHAR_aelem_bytes    = 2,
-  T_FLOAT_aelem_bytes   = 4,
-  T_DOUBLE_aelem_bytes  = 8,
-  T_BYTE_aelem_bytes    = 1,
-  T_SHORT_aelem_bytes   = 2,
-  T_INT_aelem_bytes     = 4,
-  T_LONG_aelem_bytes    = 8,
+  T_BOOLEAN_aelem_bytes     = 1,
+  T_CHAR_aelem_bytes        = 2,
+  T_FLOAT_aelem_bytes       = 4,
+  T_DOUBLE_aelem_bytes      = 8,
+  T_BYTE_aelem_bytes        = 1,
+  T_SHORT_aelem_bytes       = 2,
+  T_INT_aelem_bytes         = 4,
+  T_LONG_aelem_bytes        = 8,
 #ifdef _LP64
-  T_OBJECT_aelem_bytes  = 8,
-  T_ARRAY_aelem_bytes   = 8,
+  T_OBJECT_aelem_bytes      = 8,
+  T_ARRAY_aelem_bytes       = 8,
 #else
-  T_OBJECT_aelem_bytes  = 4,
-  T_ARRAY_aelem_bytes   = 4,
+  T_OBJECT_aelem_bytes      = 4,
+  T_ARRAY_aelem_bytes       = 4,
 #endif
-  T_NARROWOOP_aelem_bytes = 4,
-  T_VOID_aelem_bytes    = 0
+  T_NARROWOOP_aelem_bytes   = 4,
+  T_NARROWKLASS_aelem_bytes = 4,
+  T_VOID_aelem_bytes        = 0
 };
 
 extern int _type2aelembytes[T_CONFLICT+1]; // maps a BasicType to nof bytes used by its array element