6990754: Use native memory and reference counting to implement SymbolTable

Summary: move symbols from permgen into C heap and reference count them
Reviewed-by: never, acorn, jmasa, stefank

agent/src/share/classes/sun/jvm/hotspot/CommandProcessor.java

@@ -428,6 +428,36 @@ public class CommandProcessor {
                 }
             }
         },
+        new Command("symbol", "symbol address", false) {
+            public void doit(Tokens t) {
+                if (t.countTokens() != 1) {
+                    usage();
+                } else {
+                    Address a = VM.getVM().getDebugger().parseAddress(t.nextToken());
+                    Symbol.create(a).printValueOn(out);
+                    out.println();
+                }
+            }
+        },
+        new Command("symboltable", "symboltable name", false) {
+            public void doit(Tokens t) {
+                if (t.countTokens() != 1) {
+                    usage();
+                } else {
+                    out.println(SymbolTable.getTheTable().probe(t.nextToken()));
+                }
+            }
+        },
+        new Command("symboldump", "symboldump", false) {
+            public void doit(Tokens t) {
+                SymbolTable.getTheTable().symbolsDo(new SymbolTable.SymbolVisitor() {
+                        public void visit(Symbol sym) {
+                            sym.printValueOn(out);
+                            out.println();
+                        }
+                    });
+            }
+        },
         new Command("flags", "flags [ flag ]", false) {
             public void doit(Tokens t) {
                 int tokens = t.countTokens();
@@ -629,17 +659,6 @@ public class CommandProcessor {
                 }
             }
         },
-        new Command("symbol", "symbol name", false) {
-            public void doit(Tokens t) {
-                if (t.countTokens() != 1) {
-                    usage();
-                } else {
-                    String symbol = t.nextToken();
-                    Address a = lookup(symbol);
-                    out.println(symbol + " = " + a);
-                }
-            }
-        },
         new Command("printstatics", "printstatics [ type ]", false) {
             public void doit(Tokens t) {
                 if (t.countTokens() > 1) {
@@ -1262,6 +1281,9 @@ public class CommandProcessor {
         this.err = err;
         for (int i = 0; i < commandList.length; i++) {
             Command c = commandList[i];
+            if (commands.get(c.name) != null) {
+                throw new InternalError(c.name + " has multiple definitions");
+            }
             commands.put(c.name, c);
         }
         if (debugger.isAttached()) {

agent/src/share/classes/sun/jvm/hotspot/HotSpotTypeDataBase.java

@@ -89,6 +89,37 @@ public class HotSpotTypeDataBase extends BasicTypeDataBase {
     readVMLongConstants();
   }
 
+  public Type lookupType(String cTypeName, boolean throwException) {
+    Type fieldType = super.lookupType(cTypeName, false);
+    if (fieldType == null && cTypeName.startsWith("const ")) {
+      fieldType = (BasicType)lookupType(cTypeName.substring(6), false);
+    }
+    if (fieldType == null && cTypeName.endsWith(" const")) {
+        fieldType = (BasicType)lookupType(cTypeName.substring(0, cTypeName.length() - 6), false);
+    }
+    if (fieldType == null) {
+      if (cTypeName.startsWith("GrowableArray<") && cTypeName.endsWith(">*")) {
+        String ttype = cTypeName.substring("GrowableArray<".length(),
+                                            cTypeName.length() - 2);
+        Type templateType = lookupType(ttype, false);
+        if (templateType == null && typeNameIsPointerType(ttype)) {
+          templateType = recursiveCreateBasicPointerType(ttype);
+        }
+        if (templateType == null) {
+          lookupOrFail(ttype);
+        }
+        fieldType = recursiveCreateBasicPointerType(cTypeName);
+      }
+    }
+    if (fieldType == null && typeNameIsPointerType(cTypeName)) {
+      fieldType = recursiveCreateBasicPointerType(cTypeName);
+    }
+    if (fieldType == null && throwException) {
+      super.lookupType(cTypeName, true);
+    }
+    return fieldType;
+  }
+
   private void readVMTypes() {
     // Get the variables we need in order to traverse the VMTypeEntry[]
     long typeEntryTypeNameOffset;
@@ -250,7 +281,7 @@ public class HotSpotTypeDataBase extends BasicTypeDataBase {
         BasicType containingType = lookupOrFail(typeName);
 
         // The field's Type must already be in the database -- no exceptions
-        BasicType fieldType = lookupOrFail(typeString);
+        BasicType fieldType = (BasicType)lookupType(typeString);
 
         // Create field by type
         createField(containingType, fieldName, fieldType,
@@ -442,10 +473,17 @@ public class HotSpotTypeDataBase extends BasicTypeDataBase {
       workarounds due to incomplete information in the VMStructs
       database. */
   private BasicPointerType recursiveCreateBasicPointerType(String typeName) {
+    BasicPointerType result = (BasicPointerType)super.lookupType(typeName, false);
+    if (result != null) {
+      return result;
+    }
     String targetTypeName = typeName.substring(0, typeName.lastIndexOf('*')).trim();
     Type targetType = null;
     if (typeNameIsPointerType(targetTypeName)) {
+      targetType = lookupType(targetTypeName, false);
+      if (targetType == null) {
         targetType = recursiveCreateBasicPointerType(targetTypeName);
+      }
     } else {
       targetType = lookupType(targetTypeName, false);
       if (targetType == null) {
@@ -466,6 +504,20 @@ public class HotSpotTypeDataBase extends BasicTypeDataBase {
           BasicType basicTargetType = createBasicType(targetTypeName, false, true, true);
           basicTargetType.setSize(1);
           targetType = basicTargetType;
+        } else if (targetTypeName.startsWith("GrowableArray<")) {
+          BasicType basicTargetType = createBasicType(targetTypeName, false, false, false);
+
+          // transfer fields from GenericGrowableArray to template instance
+          BasicType generic = lookupOrFail("GenericGrowableArray");
+          basicTargetType.setSize(generic.getSize());
+          Iterator fields = generic.getFields();
+          while (fields.hasNext()) {
+              Field f = (Field)fields.next();
+              basicTargetType.addField(internalCreateField(basicTargetType, f.getName(),
+                                                           f.getType(), f.isStatic(),
+                                                           f.getOffset(), null));
+          }
+          targetType = basicTargetType;
         } else {
           if (DEBUG) {
             System.err.println("WARNING: missing target type \"" + targetTypeName + "\" for pointer type \"" + typeName + "\"");
@@ -474,7 +526,10 @@ public class HotSpotTypeDataBase extends BasicTypeDataBase {
         }
       }
     }
-    return new BasicPointerType(this, typeName, targetType);
+    result = new BasicPointerType(this, typeName, targetType);
+    result.setSize(UNINITIALIZED_SIZE);
+    addType(result);
+    return result;
   }
 
   private boolean typeNameIsPointerType(String typeName) {

agent/src/share/classes/sun/jvm/hotspot/interpreter/BytecodeLoadConstant.java

@@ -112,7 +112,7 @@ public class BytecodeLoadConstant extends BytecodeWithCPIndex {
   }
 
   // return Symbol (if unresolved) or Klass (if resolved)
-  public Oop getKlass() {
+  public Object getKlass() {
     if (Assert.ASSERTS_ENABLED) {
       Assert.that(isKlassConstant(), "not a klass literal");
     }
@@ -121,11 +121,11 @@ public class BytecodeLoadConstant extends BytecodeWithCPIndex {
     // decide based on the oop type.
     ConstantPool cpool = method().getConstants();
     int cpIndex = index();
-    Oop oop = cpool.getObjAt(cpIndex);
-    if (oop.isKlass()) {
-       return (Klass) oop;
-    } else if (oop.isSymbol()) {
-       return (Symbol) oop;
+    ConstantPool.CPSlot oop = cpool.getSlotAt(cpIndex);
+    if (oop.isOop()) {
+      return (Klass) oop.getOop();
+    } else if (oop.isMetaData()) {
+      return oop.getSymbol();
     } else {
        throw new RuntimeException("should not reach here");
     }
@@ -165,12 +165,12 @@ public class BytecodeLoadConstant extends BytecodeWithCPIndex {
        // tag change from 'unresolved' to 'string' does not happen atomically.
        // We just look at the object at the corresponding index and
        // decide based on the oop type.
-       Oop obj = cpool.getObjAt(cpIndex);
-       if (obj.isSymbol()) {
-          Symbol sym = (Symbol) obj;
+       ConstantPool.CPSlot obj = cpool.getSlotAt(cpIndex);
+       if (obj.isMetaData()) {
+         Symbol sym = obj.getSymbol();
          return "<String \"" + sym.asString() + "\">";
-       } else if (obj.isInstance()) {
-          return "<String \"" + OopUtilities.stringOopToString(obj) + "\">";
+       } else if (obj.isOop()) {
+         return "<String \"" + OopUtilities.stringOopToString(obj.getOop()) + "\">";
        } else {
           throw new RuntimeException("should not reach here");
        }
@@ -178,12 +178,12 @@ public class BytecodeLoadConstant extends BytecodeWithCPIndex {
        // tag change from 'unresolved' to 'klass' does not happen atomically.
        // We just look at the object at the corresponding index and
        // decide based on the oop type.
-       Oop obj = cpool.getObjAt(cpIndex);
-       if (obj.isKlass()) {
-          Klass k = (Klass) obj;
+       ConstantPool.CPSlot obj = cpool.getSlotAt(cpIndex);
+       if (obj.isOop()) {
+         Klass k = (Klass) obj.getOop();
          return "<Class " + k.getName().asString() + "@" + k.getHandle() + ">";
-       } else if (obj.isSymbol()) {
-          Symbol sym = (Symbol) obj;
+       } else if (obj.isMetaData()) {
+         Symbol sym = obj.getSymbol();
          return "<Class " + sym.asString() + ">";
        } else {
           throw new RuntimeException("should not reach here");

agent/src/share/classes/sun/jvm/hotspot/interpreter/BytecodeWithKlass.java

@@ -37,11 +37,11 @@ public class BytecodeWithKlass extends BytecodeWithCPIndex {
   }
 
   public Symbol getClassName() {
-    Oop obj = method().getConstants().getObjAt(index());
-    if (obj instanceof Symbol) {
-       return (Symbol)obj;
+    ConstantPool.CPSlot obj = method().getConstants().getSlotAt(index());
+    if (obj.isMetaData()) {
+      return obj.getSymbol();
     } else {
-       return ((Klass)obj).getName();
+      return ((Klass)obj.getOop()).getName();
     }
   }
 

agent/src/share/classes/sun/jvm/hotspot/memory/DictionaryEntry.java

@@ -63,7 +63,7 @@ public class DictionaryEntry extends sun.jvm.hotspot.utilities.HashtableEntry {
   }
 
   public Klass klass() {
-    return (Klass) literal();
+    return (Klass)VM.getVM().getObjectHeap().newOop(literalValue().addOffsetToAsOopHandle(0));
   }
 
   public DictionaryEntry(Address addr) {

agent/src/share/classes/sun/jvm/hotspot/memory/LoaderConstraintEntry.java

@@ -42,14 +42,14 @@ public class LoaderConstraintEntry extends sun.jvm.hotspot.utilities.HashtableEn
 
   private static synchronized void initialize(TypeDataBase db) {
     Type type = db.lookupType("LoaderConstraintEntry");
-    nameField = type.getOopField("_name");
+    nameField = type.getAddressField("_name");
     numLoadersField = type.getCIntegerField("_num_loaders");
     maxLoadersField = type.getCIntegerField("_max_loaders");
     loadersField = type.getAddressField("_loaders");
   }
 
   // Fields
-  private static sun.jvm.hotspot.types.OopField nameField;
+  private static AddressField nameField;
   private static CIntegerField numLoadersField;
   private static CIntegerField maxLoadersField;
   private static AddressField loadersField;
@@ -57,7 +57,7 @@ public class LoaderConstraintEntry extends sun.jvm.hotspot.utilities.HashtableEn
   // Accessors
 
   public Symbol name() {
-    return (Symbol) VM.getVM().getObjectHeap().newOop(nameField.getValue(addr));
+    return Symbol.create(nameField.getValue(addr));
   }
 
   public int numLoaders() {

agent/src/share/classes/sun/jvm/hotspot/memory/PlaceholderEntry.java

@@ -58,7 +58,7 @@ public class PlaceholderEntry extends sun.jvm.hotspot.utilities.HashtableEntry {
   }
 
   public Symbol klass() {
-    return (Symbol) literal();
+    return Symbol.create(literalValue());
   }
 
   /* covariant return type :-(

agent/src/share/classes/sun/jvm/hotspot/memory/StringTable.java

@@ -70,11 +70,13 @@ public class StringTable extends sun.jvm.hotspot.utilities.Hashtable {
   }
 
   public void stringsDo(StringVisitor visitor) {
+    ObjectHeap oh = VM.getVM().getObjectHeap();
     int numBuckets = tableSize();
     for (int i = 0; i < numBuckets; i++) {
       for (HashtableEntry e = (HashtableEntry) bucket(i); e != null;
            e = (HashtableEntry) e.next()) {
-        visitor.visit((Instance) e.literal());
+        Instance s = (Instance)oh.newOop(e.literalValue().addOffsetToAsOopHandle(0));
+        visitor.visit(s);
       }
     }
   }

agent/src/share/classes/sun/jvm/hotspot/memory/SymbolTable.java

@@ -85,7 +85,7 @@ public class SymbolTable extends sun.jvm.hotspot.utilities.Hashtable {
     long hashValue = hashSymbol(name);
     for (HashtableEntry e = (HashtableEntry) bucket(hashToIndex(hashValue)); e != null; e = (HashtableEntry) e.next()) {
       if (e.hash() == hashValue) {
-         Symbol sym = (Symbol) e.literal();
+         Symbol sym = Symbol.create(e.literalValue());
          if (sym.equals(name)) {
            return sym;
          }
@@ -103,7 +103,7 @@ public class SymbolTable extends sun.jvm.hotspot.utilities.Hashtable {
     for (int i = 0; i < numBuckets; i++) {
       for (HashtableEntry e = (HashtableEntry) bucket(i); e != null;
            e = (HashtableEntry) e.next()) {
-        visitor.visit((Symbol) e.literal());
+        visitor.visit(Symbol.create(e.literalValue()));
       }
     }
   }

agent/src/share/classes/sun/jvm/hotspot/oops/ConstantPool.java

@@ -35,6 +35,38 @@ import sun.jvm.hotspot.utilities.*;
 // as described in the class file
 
 public class ConstantPool extends Oop implements ClassConstants {
+
+  public class CPSlot {
+    private Address ptr;
+
+    CPSlot(Address ptr) {
+      this.ptr = ptr;
+    }
+    CPSlot(Symbol sym) {
+      this.ptr = sym.getAddress().orWithMask(1);
+    }
+
+    public boolean isOop() {
+      return (ptr.minus(null) & 1) == 0;
+    }
+    public boolean isMetaData() {
+      return (ptr.minus(null) & 1) == 1;
+    }
+
+    public Symbol getSymbol() {
+      if (isMetaData()) {
+        return Symbol.create(ptr.xorWithMask(1));
+      }
+      throw new InternalError("not a symbol");
+    }
+    public Oop getOop() {
+      if (isOop()) {
+        return VM.getVM().getObjectHeap().newOop(ptr.addOffsetToAsOopHandle(0));
+      }
+      throw new InternalError("not an oop");
+    }
+  }
+
   // Used for debugging this code
   private static final boolean DEBUG = false;
 
@@ -110,12 +142,17 @@ public class ConstantPool extends Oop implements ClassConstants {
     return new ConstantTag(getTags().getByteAt((int) index));
   }
 
-  public Oop getObjAt(long index){
+  public CPSlot getSlotAt(long index) {
+    return new CPSlot(getHandle().getAddressAt(indexOffset(index)));
+  }
+
+  public Oop getObjAtRaw(long index){
     return getHeap().newOop(getHandle().getOopHandleAt(indexOffset(index)));
   }
 
   public Symbol getSymbolAt(long index) {
-    return (Symbol) getObjAt(index);
+    CPSlot slot = getSlotAt(index);
+    return slot.getSymbol();
   }
 
   public int getIntAt(long index){
@@ -187,7 +224,7 @@ public class ConstantPool extends Oop implements ClassConstants {
   // returns null, if not resolved.
   public Klass getKlassRefAt(int which) {
     if( ! getTagAt(which).isKlass()) return null;
-    return (Klass) getObjAt(which);
+    return (Klass) getObjAtRaw(which);
   }
 
   // returns null, if not resolved.
@@ -477,7 +514,7 @@ public class ConstantPool extends Oop implements ClassConstants {
               case JVM_CONSTANT_Class: {
                   dos.writeByte(cpConstType);
                   // Klass already resolved. ConstantPool constains klassOop.
-                  Klass refKls = (Klass) getObjAt(ci);
+                  Klass refKls = (Klass) getObjAtRaw(ci);
                   String klassName = refKls.getName().asString();
                   Short s = (Short) utf8ToIndex.get(klassName);
                   dos.writeShort(s.shortValue());
@@ -498,7 +535,7 @@ public class ConstantPool extends Oop implements ClassConstants {
 
               case JVM_CONSTANT_String: {
                   dos.writeByte(cpConstType);
-                  String str = OopUtilities.stringOopToString(getObjAt(ci));
+                  String str = OopUtilities.stringOopToString(getObjAtRaw(ci));
                   Short s = (Short) utf8ToIndex.get(str);
                   dos.writeShort(s.shortValue());
                   if (DEBUG) debugMessage("CP[" + ci + "] = string " + s);

agent/src/share/classes/sun/jvm/hotspot/oops/GenerateOopMap.java

@@ -576,7 +576,7 @@ public class GenerateOopMap {
           ConstantPool cp       = method().getConstants();
           int nameAndTypeIdx    = cp.name_and_type_ref_index_at(idx);
           int signatureIdx      = cp.signature_ref_index_at(nameAndTypeIdx);
-          symbolOop signature   = cp.symbol_at(signatureIdx);
+          Symbol* signature     = cp.symbol_at(signatureIdx);
           tty.print("%s", signature.as_C_string());
         */
       }
@@ -616,7 +616,7 @@ public class GenerateOopMap {
           constantPoolOop cp    = method().constants();
           int nameAndTypeIdx    = cp.name_and_type_ref_index_at(idx);
           int signatureIdx      = cp.signature_ref_index_at(nameAndTypeIdx);
-          symbolOop signature   = cp.symbol_at(signatureIdx);
+          Symbol* signature     = cp.symbol_at(signatureIdx);
           tty.print("%s", signature.as_C_string());
         */
       }

agent/src/share/classes/sun/jvm/hotspot/oops/InstanceKlass.java

@@ -82,8 +82,8 @@ public class InstanceKlass extends Klass {
     classLoader          = new OopField(type.getOopField("_class_loader"), Oop.getHeaderSize());
     protectionDomain     = new OopField(type.getOopField("_protection_domain"), Oop.getHeaderSize());
     signers              = new OopField(type.getOopField("_signers"), Oop.getHeaderSize());
-    sourceFileName       = new OopField(type.getOopField("_source_file_name"), Oop.getHeaderSize());
-    sourceDebugExtension = new OopField(type.getOopField("_source_debug_extension"), Oop.getHeaderSize());
+    sourceFileName       = type.getAddressField("_source_file_name");
+    sourceDebugExtension = type.getAddressField("_source_debug_extension");
     innerClasses         = new OopField(type.getOopField("_inner_classes"), Oop.getHeaderSize());
     nonstaticFieldSize   = new CIntField(type.getCIntegerField("_nonstatic_field_size"), Oop.getHeaderSize());
     staticFieldSize      = new CIntField(type.getCIntegerField("_static_field_size"), Oop.getHeaderSize());
@@ -94,7 +94,7 @@ public class InstanceKlass extends Klass {
     vtableLen            = new CIntField(type.getCIntegerField("_vtable_len"), Oop.getHeaderSize());
     itableLen            = new CIntField(type.getCIntegerField("_itable_len"), Oop.getHeaderSize());
     breakpoints          = type.getAddressField("_breakpoints");
-    genericSignature     = new OopField(type.getOopField("_generic_signature"), Oop.getHeaderSize());
+    genericSignature     = type.getAddressField("_generic_signature");
     majorVersion         = new CIntField(type.getCIntegerField("_major_version"), Oop.getHeaderSize());
     minorVersion         = new CIntField(type.getCIntegerField("_minor_version"), Oop.getHeaderSize());
     headerSize           = alignObjectOffset(Oop.getHeaderSize() + type.getSize());
@@ -135,8 +135,8 @@ public class InstanceKlass extends Klass {
   private static OopField  classLoader;
   private static OopField  protectionDomain;
   private static OopField  signers;
-  private static OopField  sourceFileName;
-  private static OopField  sourceDebugExtension;
+  private static AddressField  sourceFileName;
+  private static AddressField  sourceDebugExtension;
   private static OopField  innerClasses;
   private static CIntField nonstaticFieldSize;
   private static CIntField staticFieldSize;
@@ -147,7 +147,7 @@ public class InstanceKlass extends Klass {
   private static CIntField vtableLen;
   private static CIntField itableLen;
   private static AddressField breakpoints;
-  private static OopField  genericSignature;
+  private static AddressField  genericSignature;
   private static CIntField majorVersion;
   private static CIntField minorVersion;
 
@@ -257,8 +257,8 @@ public class InstanceKlass extends Klass {
   public Oop       getClassLoader()         { return                classLoader.getValue(this); }
   public Oop       getProtectionDomain()    { return                protectionDomain.getValue(this); }
   public ObjArray  getSigners()             { return (ObjArray)     signers.getValue(this); }
-  public Symbol    getSourceFileName()      { return (Symbol)       sourceFileName.getValue(this); }
-  public Symbol    getSourceDebugExtension(){ return (Symbol)       sourceDebugExtension.getValue(this); }
+  public Symbol    getSourceFileName()      { return getSymbol(sourceFileName); }
+  public Symbol    getSourceDebugExtension(){ return getSymbol(sourceDebugExtension); }
   public TypeArray getInnerClasses()        { return (TypeArray)    innerClasses.getValue(this); }
   public long      getNonstaticFieldSize()  { return                nonstaticFieldSize.getValue(this); }
   public long      getStaticFieldSize()     { return                staticFieldSize.getValue(this); }
@@ -267,7 +267,7 @@ public class InstanceKlass extends Klass {
   public boolean   getIsMarkedDependent()   { return                isMarkedDependent.getValue(this) != 0; }
   public long      getVtableLen()           { return                vtableLen.getValue(this); }
   public long      getItableLen()           { return                itableLen.getValue(this); }
-  public Symbol    getGenericSignature()    { return (Symbol)       genericSignature.getValue(this); }
+  public Symbol    getGenericSignature()    { return getSymbol(genericSignature); }
   public long      majorVersion()           { return                majorVersion.getValue(this); }
   public long      minorVersion()           { return                minorVersion.getValue(this); }
 
@@ -308,12 +308,12 @@ public class InstanceKlass extends Klass {
           if (ioff != 0) {
              // only look at classes that are already loaded
              // since we are looking for the flags for our self.
-             Oop classInfo = getConstants().getObjAt(ioff);
+             ConstantPool.CPSlot classInfo = getConstants().getSlotAt(ioff);
              Symbol name = null;
-             if (classInfo instanceof Klass) {
-                name = ((Klass) classInfo).getName();
-             } else if (classInfo instanceof Symbol) {
-                name = (Symbol) classInfo;
+             if (classInfo.isOop()) {
+               name = ((Klass) classInfo.getOop()).getName();
+             } else if (classInfo.isMetaData()) {
+               name = classInfo.getSymbol();
              } else {
                 throw new RuntimeException("should not reach here");
              }
@@ -358,12 +358,12 @@ public class InstanceKlass extends Klass {
          // 'ioff' can be zero.
          // refer to JVM spec. section 4.7.5.
          if (ioff != 0) {
-            Oop iclassInfo = getConstants().getObjAt(ioff);
+            ConstantPool.CPSlot iclassInfo = getConstants().getSlotAt(ioff);
             Symbol innerName = null;
-            if (iclassInfo instanceof Klass) {
-               innerName = ((Klass) iclassInfo).getName();
-            } else if (iclassInfo instanceof Symbol) {
-               innerName = (Symbol) iclassInfo;
+            if (iclassInfo.isOop()) {
+              innerName = ((Klass) iclassInfo.getOop()).getName();
+            } else if (iclassInfo.isMetaData()) {
+              innerName = iclassInfo.getSymbol();
             } else {
                throw new RuntimeException("should not reach here");
             }
@@ -387,12 +387,12 @@ public class InstanceKlass extends Klass {
                   }
                }
             } else {
-               Oop oclassInfo = getConstants().getObjAt(ooff);
+               ConstantPool.CPSlot oclassInfo = getConstants().getSlotAt(ooff);
                Symbol outerName = null;
-               if (oclassInfo instanceof Klass) {
-                  outerName = ((Klass) oclassInfo).getName();
-               } else if (oclassInfo instanceof Symbol) {
-                  outerName = (Symbol) oclassInfo;
+               if (oclassInfo.isOop()) {
+                 outerName = ((Klass) oclassInfo.getOop()).getName();
+               } else if (oclassInfo.isMetaData()) {
+                 outerName = oclassInfo.getSymbol();
                } else {
                   throw new RuntimeException("should not reach here");
                }
@@ -450,7 +450,6 @@ public class InstanceKlass extends Klass {
       visitor.doOop(classLoader, true);
       visitor.doOop(protectionDomain, true);
       visitor.doOop(signers, true);
-      visitor.doOop(sourceFileName, true);
       visitor.doOop(innerClasses, true);
       visitor.doCInt(nonstaticFieldSize, true);
       visitor.doCInt(staticFieldSize, true);
@@ -467,7 +466,7 @@ public class InstanceKlass extends Klass {
     for (int index = 0; index < length; index += NEXT_OFFSET) {
       short accessFlags    = fields.getShortAt(index + ACCESS_FLAGS_OFFSET);
       short signatureIndex = fields.getShortAt(index + SIGNATURE_INDEX_OFFSET);
-      FieldType   type   = new FieldType((Symbol) getConstants().getObjAt(signatureIndex));
+      FieldType   type   = new FieldType(getConstants().getSymbolAt(signatureIndex));
       AccessFlags access = new AccessFlags(accessFlags);
       if (access.isStatic()) {
         visitField(visitor, type, index);
@@ -490,7 +489,7 @@ public class InstanceKlass extends Klass {
       short accessFlags    = fields.getShortAt(index + ACCESS_FLAGS_OFFSET);
       short signatureIndex = fields.getShortAt(index + SIGNATURE_INDEX_OFFSET);
 
-      FieldType   type   = new FieldType((Symbol) getConstants().getObjAt(signatureIndex));
+      FieldType   type   = new FieldType(getConstants().getSymbolAt(signatureIndex));
       AccessFlags access = new AccessFlags(accessFlags);
       if (!access.isStatic()) {
         visitField(visitor, type, index);
@@ -787,7 +786,7 @@ public class InstanceKlass extends Klass {
   private Field newField(int index) {
     TypeArray fields = getFields();
     short signatureIndex = fields.getShortAt(index + SIGNATURE_INDEX_OFFSET);
-    FieldType type = new FieldType((Symbol) getConstants().getObjAt(signatureIndex));
+    FieldType type = new FieldType(getConstants().getSymbolAt(signatureIndex));
     if (type.isOop()) {
      if (VM.getVM().isCompressedOopsEnabled()) {
         return new NarrowOopField(this, index);

agent/src/share/classes/sun/jvm/hotspot/oops/Klass.java

@@ -53,7 +53,7 @@ public class Klass extends Oop implements ClassConstants {
     javaMirror   = new OopField(type.getOopField("_java_mirror"), Oop.getHeaderSize());
     superField   = new OopField(type.getOopField("_super"), Oop.getHeaderSize());
     layoutHelper = new IntField(type.getJIntField("_layout_helper"), Oop.getHeaderSize());
-    name         = new OopField(type.getOopField("_name"), Oop.getHeaderSize());
+    name         = type.getAddressField("_name");
     accessFlags  = new CIntField(type.getCIntegerField("_access_flags"), Oop.getHeaderSize());
     subklass     = new OopField(type.getOopField("_subklass"), Oop.getHeaderSize());
     nextSibling  = new OopField(type.getOopField("_next_sibling"), Oop.getHeaderSize());
@@ -83,18 +83,26 @@ public class Klass extends Oop implements ClassConstants {
   private static OopField  javaMirror;
   private static OopField  superField;
   private static IntField layoutHelper;
-  private static OopField  name;
+  private static AddressField  name;
   private static CIntField accessFlags;
   private static OopField  subklass;
   private static OopField  nextSibling;
   private static CIntField allocCount;
 
+  private Address getValue(AddressField field) {
+    return getHandle().getAddressAt(field.getOffset() + Oop.getHeaderSize());
+  }
+
+  protected Symbol getSymbol(AddressField field) {
+    return Symbol.create(getHandle().getAddressAt(field.getOffset() + Oop.getHeaderSize()));
+  }
+
   // Accessors for declared fields
   public Instance getJavaMirror()       { return (Instance) javaMirror.getValue(this);   }
   public Klass    getSuper()            { return (Klass)    superField.getValue(this);   }
   public Klass    getJavaSuper()        { return null;  }
   public int      getLayoutHelper()     { return (int)           layoutHelper.getValue(this); }
-  public Symbol   getName()             { return (Symbol)   name.getValue(this);         }
+  public Symbol   getName()             { return getSymbol(name); }
   public long     getAccessFlags()      { return            accessFlags.getValue(this);  }
   // Convenience routine
   public AccessFlags getAccessFlagsObj(){ return new AccessFlags(getAccessFlags());      }
@@ -162,7 +170,7 @@ public class Klass extends Oop implements ClassConstants {
       visitor.doOop(javaMirror, true);
       visitor.doOop(superField, true);
       visitor.doInt(layoutHelper, true);
-      visitor.doOop(name, true);
+      // visitor.doOop(name, true);
       visitor.doCInt(accessFlags, true);
       visitor.doOop(subklass, true);
       visitor.doOop(nextSibling, true);

agent/src/share/classes/sun/jvm/hotspot/oops/Method.java

@@ -196,11 +196,11 @@ public class Method extends Oop {
   public Address      getFromCompiledCodeEntryPoint() { return fromCompiledCodeEntryPointField.getValue(this); }
   */
   // Accessors
-  public Symbol  getName()          { return (Symbol) getConstants().getObjAt(getNameIndex());         }
-  public Symbol  getSignature()     { return (Symbol) getConstants().getObjAt(getSignatureIndex());    }
+  public Symbol  getName()          { return getConstants().getSymbolAt(getNameIndex());         }
+  public Symbol  getSignature()     { return getConstants().getSymbolAt(getSignatureIndex());    }
   public Symbol  getGenericSignature() {
      long index = getGenericSignatureIndex();
-     return (index != 0L) ? (Symbol) getConstants().getObjAt(index) : null;
+     return (index != 0L) ? getConstants().getSymbolAt(index) : null;
   }
 
   // Method holder (the Klass holding this method)

agent/src/share/classes/sun/jvm/hotspot/oops/ObjectHeap.java

@@ -47,7 +47,6 @@ public class ObjectHeap {
     DEBUG = System.getProperty("sun.jvm.hotspot.oops.ObjectHeap.DEBUG") != null;
   }
 
-  private OopHandle              symbolKlassHandle;
   private OopHandle              methodKlassHandle;
   private OopHandle              constMethodKlassHandle;
   private OopHandle              methodDataKlassHandle;
@@ -68,7 +67,6 @@ public class ObjectHeap {
   private OopHandle              arrayKlassKlassHandle;
   private OopHandle              compiledICHolderKlassHandle;
 
-  private SymbolKlass            symbolKlassObj;
   private MethodKlass            methodKlassObj;
   private ConstMethodKlass       constMethodKlassObj;
   private MethodDataKlass        methodDataKlassObj;
@@ -93,9 +91,6 @@ public class ObjectHeap {
     // Lookup the roots in the object hierarchy.
     Type universeType = db.lookupType("Universe");
 
-    symbolKlassHandle         = universeType.getOopField("_symbolKlassObj").getValue();
-    symbolKlassObj            = new SymbolKlass(symbolKlassHandle, this);
-
     methodKlassHandle         = universeType.getOopField("_methodKlassObj").getValue();
     methodKlassObj            = new MethodKlass(methodKlassHandle, this);
 
@@ -199,7 +194,6 @@ public class ObjectHeap {
   public long getDoubleSize()  { return doubleSize;  }
 
   // Accessors for well-known system classes (from Universe)
-  public SymbolKlass            getSymbolKlassObj()            { return symbolKlassObj; }
   public MethodKlass            getMethodKlassObj()            { return methodKlassObj; }
   public ConstMethodKlass       getConstMethodKlassObj()       { return constMethodKlassObj; }
   public MethodDataKlass        getMethodDataKlassObj()        { return methodDataKlassObj; }
@@ -337,7 +331,6 @@ public class ObjectHeap {
     // First check if handle is one of the root objects
     if (handle.equals(methodKlassHandle))              return getMethodKlassObj();
     if (handle.equals(constMethodKlassHandle))         return getConstMethodKlassObj();
-    if (handle.equals(symbolKlassHandle))              return getSymbolKlassObj();
     if (handle.equals(constantPoolKlassHandle))        return getConstantPoolKlassObj();
     if (handle.equals(constantPoolCacheKlassHandle))   return getConstantPoolCacheKlassObj();
     if (handle.equals(instanceKlassKlassHandle))       return getInstanceKlassKlassObj();
@@ -363,7 +356,6 @@ public class ObjectHeap {
     if (klass != null) {
       if (klass.equals(methodKlassHandle))              return new Method(handle, this);
       if (klass.equals(constMethodKlassHandle))         return new ConstMethod(handle, this);
-      if (klass.equals(symbolKlassHandle))              return new Symbol(handle, this);
       if (klass.equals(constantPoolKlassHandle))        return new ConstantPool(handle, this);
       if (klass.equals(constantPoolCacheKlassHandle))   return new ConstantPoolCache(handle, this);
       if (!VM.getVM().isCore()) {

agent/src/share/classes/sun/jvm/hotspot/oops/Symbol.java

@@ -34,7 +34,7 @@ import sun.jvm.hotspot.utilities.*;
 // A Symbol is a canonicalized string.
 // All Symbols reside in global symbolTable.
 
-public class Symbol extends Oop {
+public class Symbol extends VMObject {
   static {
     VM.registerVMInitializedObserver(new Observer() {
         public void update(Observable o, Object data) {
@@ -44,9 +44,10 @@ public class Symbol extends Oop {
   }
 
   private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
-    Type type  = db.lookupType("symbolOopDesc");
-    length     = new CIntField(type.getCIntegerField("_length"), 0);
+    Type type  = db.lookupType("Symbol");
+    length     = type.getCIntegerField("_length");
     baseOffset = type.getField("_body").getOffset();
+    idHash = type.getCIntegerField("_identity_hash");
   }
 
   // Format:
@@ -55,8 +56,15 @@ public class Symbol extends Oop {
   //   [length] byte size of uft8 string
   //   ..body..
 
-  Symbol(OopHandle handle, ObjectHeap heap) {
-    super(handle, heap);
+  public static Symbol create(Address addr) {
+    if (addr == null) {
+      return null;
+    }
+    return new Symbol(addr);
+  }
+
+  Symbol(Address addr) {
+    super(addr);
   }
 
   public boolean isSymbol()            { return true; }
@@ -64,15 +72,19 @@ public class Symbol extends Oop {
   private static long baseOffset; // tells where the array part starts
 
   // Fields
-  private static CIntField length;
+  private static CIntegerField length;
 
   // Accessors for declared fields
-  public long   getLength() { return          length.getValue(this); }
+  public long   getLength() { return          length.getValue(this.addr); }
 
   public byte getByteAt(long index) {
-    return getHandle().getJByteAt(baseOffset + index);
+    return addr.getJByteAt(baseOffset + index);
   }
 
+  private static CIntegerField idHash;
+
+  public int identityHash() { return     (int)idHash.getValue(this.addr); }
+
   public boolean equals(byte[] modUTF8Chars) {
     int l = (int) getLength();
     if (l != modUTF8Chars.length) return false;
@@ -98,7 +110,9 @@ public class Symbol extends Oop {
     // Decode the byte array and return the string.
     try {
       return readModifiedUTF8(asByteArray());
-    } catch(IOException e) {
+    } catch(Exception e) {
+      System.err.println(addr);
+      e.printStackTrace();
       return null;
     }
   }
@@ -111,28 +125,13 @@ public class Symbol extends Oop {
     tty.print("#" + asString());
   }
 
-  public long getObjectSize() {
-    return alignObjectSize(baseOffset + getLength());
-  }
-
-  void iterateFields(OopVisitor visitor, boolean doVMFields) {
-    super.iterateFields(visitor, doVMFields);
-    if (doVMFields) {
-      visitor.doCInt(length, true);
-      int length = (int) getLength();
-      for (int index = 0; index < length; index++) {
-        visitor.doByte(new ByteField(new IndexableFieldIdentifier(index), baseOffset + index, false), true);
-      }
-    }
-  }
-
   /** Note: this comparison is used for vtable sorting only; it
       doesn't matter what order it defines, as long as it is a total,
-      time-invariant order Since symbolOops are in permSpace, their
+      time-invariant order Since Symbol* are in C_HEAP, their
       relative order in memory never changes, so use address
       comparison for speed. */
   public int fastCompare(Symbol other) {
-    return (int) getHandle().minus(other.getHandle());
+    return (int) addr.minus(other.addr);
   }
 
   private static String readModifiedUTF8(byte[] buf) throws IOException {

agent/src/share/classes/sun/jvm/hotspot/oops/SymbolKlass.java

-/*
- * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-package sun.jvm.hotspot.oops;
-
-import java.io.*;
-import java.util.*;
-import sun.jvm.hotspot.debugger.*;
-import sun.jvm.hotspot.runtime.*;
-import sun.jvm.hotspot.types.*;
-
-// A SymbolKlass is the klass for all Symbols
-
-public class SymbolKlass extends Klass {
-  static {
-    VM.registerVMInitializedObserver(new Observer() {
-        public void update(Observable o, Object data) {
-          initialize(VM.getVM().getTypeDataBase());
-        }
-      });
-  }
-
-  private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
-    Type type  = db.lookupType("symbolKlass");
-    headerSize = type.getSize() + Oop.getHeaderSize();
-  }
-
-  SymbolKlass(OopHandle handle, ObjectHeap heap) {
-    super(handle, heap);
-  }
-
-  private static long headerSize;
-
-  public long getObjectSize() { return alignObjectSize(headerSize); }
-
-  public void printValueOn(PrintStream tty) {
-    tty.print("SymbolKlass");
-  }
-}

agent/src/share/classes/sun/jvm/hotspot/tools/jcore/ClassWriter.java

@@ -229,7 +229,7 @@ public class ClassWriter implements /* imports */ ClassConstants
                 case JVM_CONSTANT_Class: {
                      dos.writeByte(cpConstType);
                      // Klass already resolved. ConstantPool constains klassOop.
-                     Klass refKls = (Klass) cpool.getObjAt(ci);
+                     Klass refKls = (Klass) cpool.getObjAtRaw(ci);
                      String klassName = refKls.getName().asString();
 
                      Short s = (Short) utf8ToIndex.get(klassName);
@@ -255,7 +255,7 @@ public class ClassWriter implements /* imports */ ClassConstants
 
                 case JVM_CONSTANT_String: {
                      dos.writeByte(cpConstType);
-                     String str = OopUtilities.stringOopToString(cpool.getObjAt(ci));
+                     String str = OopUtilities.stringOopToString(cpool.getObjAtRaw(ci));
                      Short s = (Short) utf8ToIndex.get(str);
                      dos.writeShort(s.shortValue());
                      if (DEBUG) debugMessage("CP[" + ci + "] = string " + s);

agent/src/share/classes/sun/jvm/hotspot/types/Field.java

@@ -56,7 +56,7 @@ import sun.jvm.hotspot.debugger.*;
     </PRE>
 
     FIXME: among other things, this interface is not sufficient to
-    describe fields which are themselves arrays (like symbolOop's
+    describe fields which are themselves arrays (like Symbol's
     jbyte _body[1]).  */
 public interface Field {
   /** Get the name of this field */

agent/src/share/classes/sun/jvm/hotspot/ui/classbrowser/HTMLGenerator.java

@@ -530,7 +530,7 @@ public class HTMLGenerator implements /* imports */ ClassConstants {
 
             case JVM_CONSTANT_Class:
                buf.cell("JVM_CONSTANT_Class");
-               Klass klass = (Klass) cpool.getObjAt(index);
+               Klass klass = (Klass) cpool.getObjAtRaw(index);
                if (klass instanceof InstanceKlass) {
                   buf.cell(genKlassLink((InstanceKlass) klass));
                } else {
@@ -555,7 +555,7 @@ public class HTMLGenerator implements /* imports */ ClassConstants {
             case JVM_CONSTANT_String:
                buf.cell("JVM_CONSTANT_String");
                buf.cell("\"" +
-                 escapeHTMLSpecialChars(OopUtilities.stringOopToString(cpool.getObjAt(index))) + "\"");
+                 escapeHTMLSpecialChars(OopUtilities.stringOopToString(cpool.getObjAtRaw(index))) + "\"");
                break;
 
             case JVM_CONSTANT_Fieldref:
@@ -672,11 +672,11 @@ public class HTMLGenerator implements /* imports */ ClassConstants {
             buf.beginTag("ul");
             for (int exp = 0; exp < exceptions.length; exp++) {
                short cpIndex = (short) exceptions[exp].getClassCPIndex();
-               Oop obj = cpool.getObjAt(cpIndex);
-               if (obj instanceof Symbol) {
-                  buf.li(((Symbol)obj).asString().replace('/', '.'));
+               ConstantPool.CPSlot obj = cpool.getSlotAt(cpIndex);
+               if (obj.isMetaData()) {
+                 buf.li((obj.getSymbol()).asString().replace('/', '.'));
                } else {
-                  buf.li(genKlassLink((InstanceKlass)obj));
+                 buf.li(genKlassLink((InstanceKlass)obj.getOop()));
                }
             }
             buf.endTag("ul");
@@ -756,7 +756,7 @@ public class HTMLGenerator implements /* imports */ ClassConstants {
                              } else if (instr instanceof BytecodeLoadConstant) {
                                 BytecodeLoadConstant ldc = (BytecodeLoadConstant) instr;
                                 if (ldc.isKlassConstant()) {
-                                   Oop oop = ldc.getKlass();
+                                   Object oop = ldc.getKlass();
                                    if (oop instanceof Klass) {
                                       buf.append("<a href='");
                                       buf.append(genKlassHref((InstanceKlass) oop));
@@ -803,13 +803,13 @@ public class HTMLGenerator implements /* imports */ ClassConstants {
                buf.cell(Integer.toString(exceptionTable.getIntAt(e + 1)));
                buf.cell(Integer.toString(exceptionTable.getIntAt(e + 2)));
                short cpIndex = (short) exceptionTable.getIntAt(e + 3);
-               Oop obj = cpIndex == 0? null : cpool.getObjAt(cpIndex);
+               ConstantPool.CPSlot obj = cpIndex == 0? null : cpool.getSlotAt(cpIndex);
                if (obj == null) {
                   buf.cell("Any");
-               } else if (obj instanceof Symbol) {
-                  buf.cell(((Symbol)obj).asString().replace('/', '.'));
+               } else if (obj.isMetaData()) {
+                 buf.cell(obj.getSymbol().asString().replace('/', '.'));
                } else {
-                  buf.cell(genKlassLink((InstanceKlass)obj));
+                 buf.cell(genKlassLink((InstanceKlass)obj.getOop()));
                }
                buf.endTag("tr");
             }

agent/src/share/classes/sun/jvm/hotspot/utilities/Hashtable.java

@@ -40,7 +40,7 @@ public class Hashtable extends BasicHashtable {
 
   private static synchronized void initialize(TypeDataBase db) {
     // just to confirm that type exists
-    Type type = db.lookupType("Hashtable");
+    Type type = db.lookupType("Hashtable<intptr_t>");
   }
 
   // derived class may return Class<? extends HashtableEntry>

agent/src/share/classes/sun/jvm/hotspot/utilities/HashtableEntry.java

@@ -41,16 +41,16 @@ public class HashtableEntry extends BasicHashtableEntry {
   }
 
   private static synchronized void initialize(TypeDataBase db) {
-    Type type = db.lookupType("HashtableEntry");
-    literalField   = type.getOopField("_literal");
+    Type type = db.lookupType("HashtableEntry<intptr_t>");
+    literalField   = type.getAddressField("_literal");
   }
 
   // Fields
-  private static OopField      literalField;
+  private static AddressField      literalField;
 
   // Accessors
-  public Oop literal() {
-    return VM.getVM().getObjectHeap().newOop(literalField.getValue(addr));
+  public Address literalValue() {
+    return literalField.getValue(addr);
   }
 
   public HashtableEntry(Address addr) {

agent/src/share/classes/sun/jvm/hotspot/utilities/HeapHprofBinWriter.java

@@ -740,7 +740,7 @@ public class HeapHprofBinWriter extends AbstractHeapGraphWriter {
         for (Iterator itr = fields.iterator(); itr.hasNext();) {
             Field field = (Field) itr.next();
             Symbol name = symTbl.probe(field.getID().getName());
-            writeObjectID(name);
+            writeSymbolID(name);
             char typeCode = (char) field.getSignature().getByteAt(0);
             int kind = signatureToHprofKind(typeCode);
             out.writeByte((byte)kind);
@@ -852,7 +852,7 @@ public class HeapHprofBinWriter extends AbstractHeapGraphWriter {
     private void writeSymbol(Symbol sym) throws IOException {
         byte[] buf = sym.asString().getBytes("UTF-8");
         writeHeader(HPROF_UTF8, buf.length + OBJ_ID_SIZE);
-        writeObjectID(sym);
+        writeSymbolID(sym);
         out.write(buf);
     }
 
@@ -869,7 +869,7 @@ public class HeapHprofBinWriter extends AbstractHeapGraphWriter {
                         out.writeInt(serialNum);
                         writeObjectID(clazz);
                         out.writeInt(DUMMY_STACK_TRACE_ID);
-                        writeObjectID(k.getName());
+                        writeSymbolID(k.getName());
                         serialNum++;
                     } catch (IOException exp) {
                         throw new RuntimeException(exp);
@@ -901,6 +901,10 @@ public class HeapHprofBinWriter extends AbstractHeapGraphWriter {
         writeObjectID(address);
     }
 
+    private void writeSymbolID(Symbol sym) throws IOException {
+        writeObjectID(getAddressValue(sym.getAddress()));
+    }
+
     private void writeObjectID(long address) throws IOException {
         if (OBJ_ID_SIZE == 4) {
             out.writeInt((int) address);

src/cpu/sparc/vm/sharedRuntime_sparc.cpp

@@ -2541,7 +2541,7 @@ nmethod *SharedRuntime::generate_dtrace_nmethod(
     in_sig_bt[i++] = bt;  // Collect remaining bits of signature
     out_sig_bt[total_c_args++] = bt;
     if( bt == T_OBJECT) {
-      symbolOop s = ss.as_symbol_or_null();
+      Symbol* s = ss.as_symbol_or_null();
       if (s == vmSymbols::java_lang_String()) {
         total_strings++;
         out_sig_bt[total_c_args-1] = T_ADDRESS;

src/cpu/x86/vm/sharedRuntime_x86_32.cpp

@@ -1974,7 +1974,7 @@ nmethod *SharedRuntime::generate_dtrace_nmethod(
     in_sig_bt[i++] = bt;  // Collect remaining bits of signature
     out_sig_bt[total_c_args++] = bt;
     if( bt == T_OBJECT) {
-      symbolOop s = ss.as_symbol_or_null();
+      Symbol* s = ss.as_symbol_or_null();   // symbol is created
       if (s == vmSymbols::java_lang_String()) {
         total_strings++;
         out_sig_bt[total_c_args-1] = T_ADDRESS;

src/cpu/x86/vm/sharedRuntime_x86_64.cpp

@@ -1980,7 +1980,7 @@ nmethod *SharedRuntime::generate_dtrace_nmethod(MacroAssembler *masm,
     in_sig_bt[i++] = bt;  // Collect remaining bits of signature
     out_sig_bt[total_c_args++] = bt;
     if( bt == T_OBJECT) {
-      symbolOop s = ss.as_symbol_or_null();
+      Symbol* s = ss.as_symbol_or_null();   // symbol is created
       if (s == vmSymbols::java_lang_String()) {
         total_strings++;
         out_sig_bt[total_c_args-1] = T_ADDRESS;

src/os/solaris/dtrace/generateJvmOffsets.cpp

@@ -49,7 +49,7 @@
 #include "oops/klass.hpp"
 #include "oops/methodOop.hpp"
 #include "oops/oop.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "runtime/virtualspace.hpp"
 #include "runtime/vmStructs.hpp"
 #include "utilities/accessFlags.hpp"
@@ -215,8 +215,8 @@ int generateJvmOffsets(GEN_variant gen_variant) {
   GEN_VALUE(AccessFlags_NATIVE, JVM_ACC_NATIVE);
   GEN_VALUE(constMethodOopDesc_has_linenumber_table, constMethodOopDesc::_has_linenumber_table);
   GEN_OFFS(AccessFlags, _flags);
-  GEN_OFFS(symbolOopDesc, _length);
-  GEN_OFFS(symbolOopDesc, _body);
+  GEN_OFFS(Symbol, _length);
+  GEN_OFFS(Symbol, _body);
   printf("\n");
 
   GEN_OFFS(methodOopDesc, _constMethod);

src/os/solaris/dtrace/jhelper.d

@@ -114,8 +114,8 @@ dtrace:helper:ustack:
   copyin_offset(OFFSET_HeapBlockHeader_used);
   copyin_offset(OFFSET_oopDesc_metadata);
 
-  copyin_offset(OFFSET_symbolOopDesc_length);
-  copyin_offset(OFFSET_symbolOopDesc_body);
+  copyin_offset(OFFSET_Symbol_length);
+  copyin_offset(OFFSET_Symbol_body);
 
   copyin_offset(OFFSET_methodOopDesc_constMethod);
   copyin_offset(OFFSET_methodOopDesc_constants);
@@ -366,13 +366,13 @@ dtrace:helper:ustack:
       this->nameIndex * sizeof (pointer) + SIZE_constantPoolOopDesc);
 
   this->nameSymbolLength = copyin_uint16(this->nameSymbol +
-      OFFSET_symbolOopDesc_length);
+      OFFSET_Symbol_length);
 
   this->signatureSymbol = copyin_ptr(this->constantPool +
       this->signatureIndex * sizeof (pointer) + SIZE_constantPoolOopDesc);
 
   this->signatureSymbolLength = copyin_uint16(this->signatureSymbol +
-      OFFSET_symbolOopDesc_length);
+      OFFSET_Symbol_length);
 
   this->klassPtr = copyin_ptr(this->constantPool +
       OFFSET_constantPoolOopDesc_pool_holder);
@@ -381,7 +381,7 @@ dtrace:helper:ustack:
       OFFSET_Klass_name + SIZE_oopDesc);
 
   this->klassSymbolLength = copyin_uint16(this->klassSymbol +
-      OFFSET_symbolOopDesc_length);
+      OFFSET_Symbol_length);
 
   /*
    * Enough for three strings, plus the '.', plus the trailing '\0'.
@@ -390,7 +390,7 @@ dtrace:helper:ustack:
       this->nameSymbolLength +
       this->signatureSymbolLength + 2 + 1);
 
-  copyinto(this->klassSymbol + OFFSET_symbolOopDesc_body,
+  copyinto(this->klassSymbol + OFFSET_Symbol_body,
       this->klassSymbolLength, this->result);
 
   /*
@@ -398,11 +398,11 @@ dtrace:helper:ustack:
    */
   this->result[this->klassSymbolLength] = '.';
 
-  copyinto(this->nameSymbol + OFFSET_symbolOopDesc_body,
+  copyinto(this->nameSymbol + OFFSET_Symbol_body,
       this->nameSymbolLength,
       this->result + this->klassSymbolLength + 1);
 
-  copyinto(this->signatureSymbol + OFFSET_symbolOopDesc_body,
+  copyinto(this->signatureSymbol + OFFSET_Symbol_body,
       this->signatureSymbolLength,
       this->result + this->klassSymbolLength +
       this->nameSymbolLength + 1);

src/os/solaris/dtrace/libjvm_db.c

@@ -524,10 +524,10 @@ name_for_methodOop(jvm_agent_t* J, uint64_t methodOopPtr, char * result, size_t
   CHECK_FAIL(err);
   err = read_pointer(J, constantPool + nameIndex * POINTER_SIZE + SIZE_constantPoolOopDesc, &nameSymbol);
   CHECK_FAIL(err);
-  err = ps_pread(J->P, nameSymbol + OFFSET_symbolOopDesc_length, &nameSymbolLength, 2);
+  err = ps_pread(J->P, nameSymbol + OFFSET_Symbol_length, &nameSymbolLength, 2);
   CHECK_FAIL(err);
   nameString = (char*)calloc(nameSymbolLength + 1, 1);
-  err = ps_pread(J->P, nameSymbol + OFFSET_symbolOopDesc_body, nameString, nameSymbolLength);
+  err = ps_pread(J->P, nameSymbol + OFFSET_Symbol_body, nameString, nameSymbolLength);
   CHECK_FAIL(err);
 
   /* To get signature string */
@@ -535,10 +535,10 @@ name_for_methodOop(jvm_agent_t* J, uint64_t methodOopPtr, char * result, size_t
   CHECK_FAIL(err);
   err = read_pointer(J, constantPool + signatureIndex * POINTER_SIZE + SIZE_constantPoolOopDesc, &signatureSymbol);
   CHECK_FAIL(err);
-  err = ps_pread(J->P, signatureSymbol + OFFSET_symbolOopDesc_length, &signatureSymbolLength, 2);
+  err = ps_pread(J->P, signatureSymbol + OFFSET_Symbol_length, &signatureSymbolLength, 2);
   CHECK_FAIL(err);
   signatureString = (char*)calloc(signatureSymbolLength + 1, 1);
-  err = ps_pread(J->P, signatureSymbol + OFFSET_symbolOopDesc_body, signatureString, signatureSymbolLength);
+  err = ps_pread(J->P, signatureSymbol + OFFSET_Symbol_body, signatureString, signatureSymbolLength);
   CHECK_FAIL(err);
 
   /* To get klass string */
@@ -546,10 +546,10 @@ name_for_methodOop(jvm_agent_t* J, uint64_t methodOopPtr, char * result, size_t
   CHECK_FAIL(err);
   err = read_pointer(J, klassPtr + OFFSET_Klass_name + SIZE_oopDesc, &klassSymbol);
   CHECK_FAIL(err);
-  err = ps_pread(J->P, klassSymbol + OFFSET_symbolOopDesc_length, &klassSymbolLength, 2);
+  err = ps_pread(J->P, klassSymbol + OFFSET_Symbol_length, &klassSymbolLength, 2);
   CHECK_FAIL(err);
   klassString = (char*)calloc(klassSymbolLength + 1, 1);
-  err = ps_pread(J->P, klassSymbol + OFFSET_symbolOopDesc_body, klassString, klassSymbolLength);
+  err = ps_pread(J->P, klassSymbol + OFFSET_Symbol_body, klassString, klassSymbolLength);
   CHECK_FAIL(err);
 
   result[0] = '\0';

src/os/solaris/vm/dtraceJSDT_solaris.cpp

@@ -142,7 +142,7 @@ int DTraceJSDT::pd_activate(
     ++strcount;
     for(int prbc = 0; prbc < provider->probe_count; ++prbc) {
       JVM_DTraceProbe* p = &(provider->probes[prbc]);
-      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
+      Symbol* sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
       // function + name + one per argument
       strcount += 2 + ArgumentCount(sig).size();
     }
@@ -178,7 +178,7 @@ int DTraceJSDT::pd_activate(
       stroffs[curstr++] = string_index;
       string_index += strlen(name) + 1;
 
-      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
+      Symbol* sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
       SignatureStream ss(sig);
       for ( ; !ss.at_return_type(); ss.next()) {
         BasicType bt = ss.type();
@@ -227,7 +227,7 @@ int DTraceJSDT::pd_activate(
     uint32_t argscount = 0;
     for(int prbc = 0; prbc < provider->probe_count; ++prbc) {
        JVM_DTraceProbe* p = &(provider->probes[prbc]);
-       symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
+       Symbol* sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
        argscount += ArgumentCount(sig).size();
     }
     secoffs[argoffs_sec] = align_size_up(offset, alignment_for[ARG_OFFSETS]);
@@ -298,7 +298,7 @@ int DTraceJSDT::pd_activate(
       strcpy(str, name);
       str += strlen(name) + 1;
 
-      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
+      Symbol* sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
       SignatureStream ss(sig);
       for ( ; !ss.at_return_type(); ss.next()) {
         BasicType bt = ss.type();
@@ -433,7 +433,7 @@ int DTraceJSDT::pd_activate(
     uint8_t* par = (uint8_t*)(dof + sec->dofs_offset);
     for (int prbc = 0; prbc < provider->probe_count; ++prbc) {
       JVM_DTraceProbe* p = &(provider->probes[prbc]);
-      symbolOop sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
+      Symbol* sig = JNIHandles::resolve_jmethod_id(p->method)->signature();
       uint8_t count = (uint8_t)ArgumentCount(sig).size();
       for (uint8_t i = 0; i < count; ++i) {
         *par++ = i;

src/share/vm/ci/ciClassList.hpp

@@ -60,7 +60,6 @@ class    ciReturnAddress;
 class    ciKlass;
 class     ciInstanceKlass;
 class     ciMethodKlass;
-class     ciSymbolKlass;
 class     ciArrayKlass;
 class       ciObjArrayKlass;
 class       ciTypeArrayKlass;
@@ -112,7 +111,6 @@ friend class ciReturnAddress;          \
 friend class ciKlass;                  \
 friend class ciInstanceKlass;          \
 friend class ciMethodKlass;            \
-friend class ciSymbolKlass;            \
 friend class ciArrayKlass;             \
 friend class ciObjArrayKlass;          \
 friend class ciTypeArrayKlass;         \

src/share/vm/ci/ciEnv.cpp

@@ -68,7 +68,6 @@
 
 ciObject*              ciEnv::_null_object_instance;
 ciMethodKlass*         ciEnv::_method_klass_instance;
-ciSymbolKlass*         ciEnv::_symbol_klass_instance;
 ciKlassKlass*          ciEnv::_klass_klass_instance;
 ciInstanceKlassKlass*  ciEnv::_instance_klass_klass_instance;
 ciTypeArrayKlassKlass* ciEnv::_type_array_klass_klass_instance;
@@ -202,6 +201,7 @@ ciEnv::ciEnv(Arena* arena) {
 
 ciEnv::~ciEnv() {
   CompilerThread* current_thread = CompilerThread::current();
+  _factory->remove_symbols();
   current_thread->set_env(NULL);
 }
 
@@ -234,7 +234,7 @@ void ciEnv::cache_dtrace_flags() {
 
 // ------------------------------------------------------------------
 // helper for lazy exception creation
-ciInstance* ciEnv::get_or_create_exception(jobject& handle, symbolHandle name) {
+ciInstance* ciEnv::get_or_create_exception(jobject& handle, Symbol* name) {
   VM_ENTRY_MARK;
   if (handle == NULL) {
     // Cf. universe.cpp, creation of Universe::_null_ptr_exception_instance.
@@ -261,7 +261,7 @@ ciInstance* ciEnv::ArrayIndexOutOfBoundsException_instance() {
   if (_ArrayIndexOutOfBoundsException_instance == NULL) {
     _ArrayIndexOutOfBoundsException_instance
           = get_or_create_exception(_ArrayIndexOutOfBoundsException_handle,
-          vmSymbolHandles::java_lang_ArrayIndexOutOfBoundsException());
+          vmSymbols::java_lang_ArrayIndexOutOfBoundsException());
   }
   return _ArrayIndexOutOfBoundsException_instance;
 }
@@ -269,7 +269,7 @@ ciInstance* ciEnv::ArrayStoreException_instance() {
   if (_ArrayStoreException_instance == NULL) {
     _ArrayStoreException_instance
           = get_or_create_exception(_ArrayStoreException_handle,
-          vmSymbolHandles::java_lang_ArrayStoreException());
+          vmSymbols::java_lang_ArrayStoreException());
   }
   return _ArrayStoreException_instance;
 }
@@ -277,7 +277,7 @@ ciInstance* ciEnv::ClassCastException_instance() {
   if (_ClassCastException_instance == NULL) {
     _ClassCastException_instance
           = get_or_create_exception(_ClassCastException_handle,
-          vmSymbolHandles::java_lang_ClassCastException());
+          vmSymbols::java_lang_ClassCastException());
   }
   return _ClassCastException_instance;
 }
@@ -377,14 +377,16 @@ ciKlass* ciEnv::get_klass_by_name_impl(ciKlass* accessing_klass,
   EXCEPTION_CONTEXT;
 
   // Now we need to check the SystemDictionary
-  symbolHandle sym(THREAD, name->get_symbolOop());
+  Symbol* sym = name->get_symbol();
   if (sym->byte_at(0) == 'L' &&
     sym->byte_at(sym->utf8_length()-1) == ';') {
     // This is a name from a signature.  Strip off the trimmings.
-    sym = oopFactory::new_symbol_handle(sym->as_utf8()+1,
+    // Call recursive to keep scope of strippedsym.
+    TempNewSymbol strippedsym = SymbolTable::new_symbol(sym->as_utf8()+1,
                     sym->utf8_length()-2,
                     KILL_COMPILE_ON_FATAL_(_unloaded_ciinstance_klass));
-    name = get_object(sym())->as_symbol();
+    ciSymbol* strippedname = get_symbol(strippedsym);
+    return get_klass_by_name_impl(accessing_klass, strippedname, require_local);
   }
 
   // Check for prior unloaded klass.  The SystemDictionary's answers
@@ -430,13 +432,14 @@ ciKlass* ciEnv::get_klass_by_name_impl(ciKlass* accessing_klass,
       (sym->byte_at(1) == '[' || sym->byte_at(1) == 'L')) {
     // We have an unloaded array.
     // Build it on the fly if the element class exists.
-    symbolOop elem_sym = oopFactory::new_symbol(sym->as_utf8()+1,
+    TempNewSymbol elem_sym = SymbolTable::new_symbol(sym->as_utf8()+1,
                                                  sym->utf8_length()-1,
                                                  KILL_COMPILE_ON_FATAL_(fail_type));
+
     // Get element ciKlass recursively.
     ciKlass* elem_klass =
       get_klass_by_name_impl(accessing_klass,
-                             get_object(elem_sym)->as_symbol(),
+                             get_symbol(elem_sym),
                              require_local);
     if (elem_klass != NULL && elem_klass->is_loaded()) {
       // Now make an array for it
@@ -475,7 +478,7 @@ ciKlass* ciEnv::get_klass_by_index_impl(constantPoolHandle cpool,
                                         ciInstanceKlass* accessor) {
   EXCEPTION_CONTEXT;
   KlassHandle klass (THREAD, constantPoolOopDesc::klass_at_if_loaded(cpool, index));
-  symbolHandle klass_name;
+  Symbol* klass_name = NULL;
   if (klass.is_null()) {
     // The klass has not been inserted into the constant pool.
     // Try to look it up by name.
@@ -490,10 +493,10 @@ ciKlass* ciEnv::get_klass_by_index_impl(constantPoolHandle cpool,
         // very recently.
         klass = KlassHandle(THREAD, cpool->resolved_klass_at(index));
       } else if (tag.is_symbol()) {
-        klass_name = symbolHandle(THREAD, cpool->symbol_at(index));
+        klass_name = cpool->symbol_at(index);
       } else {
         assert(cpool->tag_at(index).is_unresolved_klass(), "wrong tag");
-        klass_name = symbolHandle(THREAD, cpool->unresolved_klass_at(index));
+        klass_name = cpool->unresolved_klass_at(index);
       }
     }
   }
@@ -501,7 +504,7 @@ ciKlass* ciEnv::get_klass_by_index_impl(constantPoolHandle cpool,
   if (klass.is_null()) {
     // Not found in constant pool.  Use the name to do the lookup.
     ciKlass* k = get_klass_by_name_impl(accessor,
-                                        get_object(klass_name())->as_symbol(),
+                                        get_symbol(klass_name),
                                         false);
     // Calculate accessibility the hard way.
     if (!k->is_loaded()) {
@@ -519,7 +522,7 @@ ciKlass* ciEnv::get_klass_by_index_impl(constantPoolHandle cpool,
 
   // Check for prior unloaded klass.  The SystemDictionary's answers
   // can vary over time but the compiler needs consistency.
-  ciSymbol* name = get_object(klass()->klass_part()->name())->as_symbol();
+  ciSymbol* name = get_symbol(klass()->klass_part()->name());
   ciKlass* unloaded_klass = check_get_unloaded_klass(accessor, name);
   if (unloaded_klass != NULL) {
     is_accessible = false;
@@ -605,7 +608,7 @@ ciConstant ciEnv::get_constant_by_index_impl(constantPoolHandle cpool,
     return ciConstant(T_OBJECT, ciobj);
   } else if (tag.is_method_type()) {
     // must execute Java code to link this CP entry into cache[i].f1
-    ciSymbol* signature = get_object(cpool->method_type_signature_at(index))->as_symbol();
+    ciSymbol* signature = get_symbol(cpool->method_type_signature_at(index));
     ciObject* ciobj = get_unloaded_method_type_constant(signature);
     return ciConstant(T_OBJECT, ciobj);
   } else if (tag.is_method_handle()) {
@@ -613,8 +616,8 @@ ciConstant ciEnv::get_constant_by_index_impl(constantPoolHandle cpool,
     int ref_kind        = cpool->method_handle_ref_kind_at(index);
     int callee_index    = cpool->method_handle_klass_index_at(index);
     ciKlass* callee     = get_klass_by_index_impl(cpool, callee_index, ignore_will_link, accessor);
-    ciSymbol* name      = get_object(cpool->method_handle_name_ref_at(index))->as_symbol();
-    ciSymbol* signature = get_object(cpool->method_handle_signature_ref_at(index))->as_symbol();
+    ciSymbol* name      = get_symbol(cpool->method_handle_name_ref_at(index));
+    ciSymbol* signature = get_symbol(cpool->method_handle_signature_ref_at(index));
     ciObject* ciobj     = get_unloaded_method_handle_constant(callee, name, signature, ref_kind);
     return ciConstant(T_OBJECT, ciobj);
   } else {
@@ -674,33 +677,31 @@ ciField* ciEnv::get_field_by_index(ciInstanceKlass* accessor,
 // name, signature, and bytecode.
 methodOop ciEnv::lookup_method(instanceKlass*  accessor,
                                instanceKlass*  holder,
-                               symbolOop       name,
-                               symbolOop       sig,
+                               Symbol*       name,
+                               Symbol*       sig,
                                Bytecodes::Code bc) {
   EXCEPTION_CONTEXT;
   KlassHandle h_accessor(THREAD, accessor);
   KlassHandle h_holder(THREAD, holder);
-  symbolHandle h_name(THREAD, name);
-  symbolHandle h_sig(THREAD, sig);
   LinkResolver::check_klass_accessability(h_accessor, h_holder, KILL_COMPILE_ON_FATAL_(NULL));
   methodHandle dest_method;
   switch (bc) {
   case Bytecodes::_invokestatic:
     dest_method =
-      LinkResolver::resolve_static_call_or_null(h_holder, h_name, h_sig, h_accessor);
+      LinkResolver::resolve_static_call_or_null(h_holder, name, sig, h_accessor);
     break;
   case Bytecodes::_invokespecial:
     dest_method =
-      LinkResolver::resolve_special_call_or_null(h_holder, h_name, h_sig, h_accessor);
+      LinkResolver::resolve_special_call_or_null(h_holder, name, sig, h_accessor);
     break;
   case Bytecodes::_invokeinterface:
     dest_method =
-      LinkResolver::linktime_resolve_interface_method_or_null(h_holder, h_name, h_sig,
+      LinkResolver::linktime_resolve_interface_method_or_null(h_holder, name, sig,
                                                               h_accessor, true);
     break;
   case Bytecodes::_invokevirtual:
     dest_method =
-      LinkResolver::linktime_resolve_virtual_method_or_null(h_holder, h_name, h_sig,
+      LinkResolver::linktime_resolve_virtual_method_or_null(h_holder, name, sig,
                                                             h_accessor, true);
     break;
   default: ShouldNotReachHere();
@@ -721,8 +722,8 @@ ciMethod* ciEnv::get_method_by_index_impl(constantPoolHandle cpool,
   ciInstanceKlass* declared_holder = get_instance_klass_for_declared_method_holder(holder);
 
   // Get the method's name and signature.
-  symbolOop name_sym = cpool->name_ref_at(index);
-  symbolOop sig_sym  = cpool->signature_ref_at(index);
+  Symbol* name_sym = cpool->name_ref_at(index);
+  Symbol* sig_sym  = cpool->signature_ref_at(index);
 
   if (holder_is_accessible) { // Our declared holder is loaded.
     instanceKlass* lookup = declared_holder->get_instanceKlass();
@@ -738,8 +739,8 @@ ciMethod* ciEnv::get_method_by_index_impl(constantPoolHandle cpool,
   // lookup.
 
   return get_unloaded_method(declared_holder,
-                             get_object(name_sym)->as_symbol(),
-                             get_object(sig_sym)->as_symbol());
+                             get_symbol(name_sym),
+                             get_symbol(sig_sym));
 }
 
 
@@ -759,7 +760,7 @@ ciMethod* ciEnv::get_fake_invokedynamic_method_impl(constantPoolHandle cpool,
   // compiler, but it is simpler to stop the code path here with an unlinked method.
   if (!is_resolved) {
     ciInstanceKlass* mh_klass = get_object(SystemDictionary::MethodHandle_klass())->as_instance_klass();
-    ciSymbol*        sig_sym  = get_object(cpool->signature_ref_at(index))->as_symbol();
+    ciSymbol*        sig_sym  = get_symbol(cpool->signature_ref_at(index));
     return get_unloaded_method(mh_klass, ciSymbol::invokeExact_name(), sig_sym);
   }
 

src/share/vm/ci/ciEnv.hpp

@@ -79,7 +79,6 @@ private:
   // Distinguished instances of certain ciObjects..
   static ciObject*              _null_object_instance;
   static ciMethodKlass*         _method_klass_instance;
-  static ciSymbolKlass*         _symbol_klass_instance;
   static ciKlassKlass*          _klass_klass_instance;
   static ciInstanceKlassKlass*  _instance_klass_klass_instance;
   static ciTypeArrayKlassKlass* _type_array_klass_klass_instance;
@@ -160,8 +159,8 @@ private:
                                       klassOop resolved_klassOop);
   methodOop  lookup_method(instanceKlass*  accessor,
                            instanceKlass*  holder,
-                           symbolOop       name,
-                           symbolOop       sig,
+                           Symbol*         name,
+                           Symbol*         sig,
                            Bytecodes::Code bc);
 
   // Get a ciObject from the object factory.  Ensures uniqueness
@@ -174,9 +173,18 @@ private:
     }
   }
 
+  ciSymbol* get_symbol(Symbol* o) {
+    if (o == NULL) {
+      ShouldNotReachHere();
+      return NULL;
+    } else {
+      return _factory->get_symbol(o);
+    }
+  }
+
   ciMethod* get_method_from_handle(jobject method);
 
-  ciInstance* get_or_create_exception(jobject& handle, symbolHandle name);
+  ciInstance* get_or_create_exception(jobject& handle, Symbol* name);
 
   // Get a ciMethod representing either an unfound method or
   // a method with an unloaded holder.  Ensures uniqueness of

src/share/vm/ci/ciField.cpp

@@ -79,15 +79,15 @@ ciField::ciField(ciInstanceKlass* klass, int index): _known_to_link_with(NULL) {
   constantPoolHandle cpool(thread, klass->get_instanceKlass()->constants());
 
   // Get the field's name, signature, and type.
-  symbolHandle name  (thread, cpool->name_ref_at(index));
-  _name = ciEnv::current(thread)->get_object(name())->as_symbol();
+  Symbol* name  = cpool->name_ref_at(index);
+  _name = ciEnv::current(thread)->get_symbol(name);
 
   int nt_index = cpool->name_and_type_ref_index_at(index);
   int sig_index = cpool->signature_ref_index_at(nt_index);
-  symbolHandle signature (thread, cpool->symbol_at(sig_index));
-  _signature = ciEnv::current(thread)->get_object(signature())->as_symbol();
+  Symbol* signature = cpool->symbol_at(sig_index);
+  _signature = ciEnv::current(thread)->get_symbol(signature);
 
-  BasicType field_type = FieldType::basic_type(signature());
+  BasicType field_type = FieldType::basic_type(signature);
 
   // If the field is a pointer type, get the klass of the
   // field.
@@ -100,7 +100,7 @@ ciField::ciField(ciInstanceKlass* klass, int index): _known_to_link_with(NULL) {
     _type = ciType::make(field_type);
   }
 
-  _name = (ciSymbol*)ciEnv::current(thread)->get_object(name());
+  _name = (ciSymbol*)ciEnv::current(thread)->get_symbol(name);
 
   // Get the field's declared holder.
   //
@@ -130,7 +130,7 @@ ciField::ciField(ciInstanceKlass* klass, int index): _known_to_link_with(NULL) {
   // Perform the field lookup.
   fieldDescriptor field_desc;
   klassOop canonical_holder =
-    loaded_decl_holder->find_field(name(), signature(), &field_desc);
+    loaded_decl_holder->find_field(name, signature, &field_desc);
   if (canonical_holder == NULL) {
     // Field lookup failed.  Will be detected by will_link.
     _holder = declared_holder;
@@ -150,8 +150,8 @@ ciField::ciField(fieldDescriptor *fd): _known_to_link_with(NULL) {
 
   // Get the field's name, signature, and type.
   ciEnv* env = CURRENT_ENV;
-  _name = env->get_object(fd->name())->as_symbol();
-  _signature = env->get_object(fd->signature())->as_symbol();
+  _name = env->get_symbol(fd->name());
+  _signature = env->get_symbol(fd->signature());
 
   BasicType field_type = fd->field_type();
 

src/share/vm/ci/ciInstanceKlass.cpp

@@ -380,7 +380,7 @@ ciField* ciInstanceKlass::get_field_by_name(ciSymbol* name, ciSymbol* signature,
   VM_ENTRY_MARK;
   instanceKlass* k = get_instanceKlass();
   fieldDescriptor fd;
-  klassOop def = k->find_field(name->get_symbolOop(), signature->get_symbolOop(), is_static, &fd);
+  klassOop def = k->find_field(name->get_symbol(), signature->get_symbol(), is_static, &fd);
   if (def == NULL) {
     return NULL;
   }
@@ -541,8 +541,8 @@ ciInstanceKlass::compute_nonstatic_fields_impl(GrowableArray<ciField*>*
 ciMethod* ciInstanceKlass::find_method(ciSymbol* name, ciSymbol* signature) {
   VM_ENTRY_MARK;
   instanceKlass* k = get_instanceKlass();
-  symbolOop name_sym = name->get_symbolOop();
-  symbolOop sig_sym= signature->get_symbolOop();
+  Symbol* name_sym = name->get_symbol();
+  Symbol* sig_sym= signature->get_symbol();
 
   methodOop m = k->find_method(name_sym, sig_sym);
   if (m == NULL)  return NULL;

src/share/vm/ci/ciKlass.cpp

@@ -39,9 +39,9 @@ ciKlass::ciKlass(KlassHandle h_k) : ciType(h_k) {
   assert(get_oop()->is_klass(), "wrong type");
   Klass* k = get_Klass();
   _layout_helper = k->layout_helper();
-  symbolOop klass_name = k->name();
+  Symbol* klass_name = k->name();
   assert(klass_name != NULL, "wrong ciKlass constructor");
-  _name = CURRENT_ENV->get_object(klass_name)->as_symbol();
+  _name = CURRENT_ENV->get_symbol(klass_name);
 }
 
 // ------------------------------------------------------------------

src/share/vm/ci/ciMethod.cpp

@@ -122,9 +122,9 @@ ciMethod::ciMethod(methodHandle h_m) : ciObject(h_m) {
 
   // generating _signature may allow GC and therefore move m.
   // These fields are always filled in.
-  _name = env->get_object(h_m()->name())->as_symbol();
+  _name = env->get_symbol(h_m()->name());
   _holder = env->get_object(h_m()->method_holder())->as_instance_klass();
-  ciSymbol* sig_symbol = env->get_object(h_m()->signature())->as_symbol();
+  ciSymbol* sig_symbol = env->get_symbol(h_m()->signature());
   _signature = new (env->arena()) ciSignature(_holder, sig_symbol);
   _method_data = NULL;
   // Take a snapshot of these values, so they will be commensurate with the MDO.
@@ -649,8 +649,8 @@ ciMethod* ciMethod::resolve_invoke(ciKlass* caller, ciKlass* exact_receiver) {
    KlassHandle caller_klass (THREAD, caller->get_klassOop());
    KlassHandle h_recv       (THREAD, exact_receiver->get_klassOop());
    KlassHandle h_resolved   (THREAD, holder()->get_klassOop());
-   symbolHandle h_name      (THREAD, name()->get_symbolOop());
-   symbolHandle h_signature (THREAD, signature()->get_symbolOop());
+   Symbol* h_name      = name()->get_symbol();
+   Symbol* h_signature = signature()->get_symbol();
 
    methodHandle m;
    // Only do exact lookup if receiver klass has been linked.  Otherwise,
@@ -702,8 +702,8 @@ int ciMethod::resolve_vtable_index(ciKlass* caller, ciKlass* receiver) {
 
      KlassHandle caller_klass (THREAD, caller->get_klassOop());
      KlassHandle h_recv       (THREAD, receiver->get_klassOop());
-     symbolHandle h_name      (THREAD, name()->get_symbolOop());
-     symbolHandle h_signature (THREAD, signature()->get_symbolOop());
+     Symbol* h_name = name()->get_symbol();
+     Symbol* h_signature = signature()->get_symbol();
 
      vtable_index = LinkResolver::resolve_virtual_vtable_index(h_recv, h_recv, h_name, h_signature, caller_klass);
      if (vtable_index == methodOopDesc::nonvirtual_vtable_index) {

src/share/vm/ci/ciObjArrayKlass.cpp

@@ -110,7 +110,7 @@ ciSymbol* ciObjArrayKlass::construct_array_name(ciSymbol* element_name,
   EXCEPTION_CONTEXT;
   int element_len = element_name->utf8_length();
 
-  symbolOop base_name_sym = element_name->get_symbolOop();
+  Symbol* base_name_sym = element_name->get_symbol();
   char* name;
 
   if (base_name_sym->byte_at(0) == '[' ||

src/share/vm/ci/ciObject.hpp

@@ -268,10 +268,6 @@ public:
     assert(is_type_array_klass(), "bad cast");
     return (ciTypeArrayKlass*)this;
   }
-  ciSymbolKlass*           as_symbol_klass() {
-    assert(is_symbol_klass(), "bad cast");
-    return (ciSymbolKlass*)this;
-  }
   ciKlassKlass*            as_klass_klass() {
     assert(is_klass_klass(), "bad cast");
     return (ciKlassKlass*)this;

src/share/vm/ci/ciObjectFactory.cpp

@@ -38,7 +38,6 @@
 #include "ci/ciObjArrayKlassKlass.hpp"
 #include "ci/ciObjectFactory.hpp"
 #include "ci/ciSymbol.hpp"
-#include "ci/ciSymbolKlass.hpp"
 #include "ci/ciTypeArray.hpp"
 #include "ci/ciTypeArrayKlass.hpp"
 #include "ci/ciTypeArrayKlassKlass.hpp"
@@ -98,6 +97,8 @@ ciObjectFactory::ciObjectFactory(Arena* arena,
   _unloaded_instances = new (arena) GrowableArray<ciInstance*>(arena, 4, 0, NULL);
   _return_addresses =
     new (arena) GrowableArray<ciReturnAddress*>(arena, 8, 0, NULL);
+
+  _symbols = new (arena) GrowableArray<ciSymbol*>(arena, 100, 0, NULL);
 }
 
 // ------------------------------------------------------------------
@@ -127,19 +128,19 @@ void ciObjectFactory::init_shared_objects() {
     // Create the shared symbols, but not in _shared_ci_objects.
     int i;
     for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {
-      symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);
-      assert(vmSymbols::find_sid(sym_handle()) == i, "1-1 mapping");
-      ciSymbol* sym = new (_arena) ciSymbol(sym_handle, (vmSymbols::SID) i);
+      Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);
+      assert(vmSymbols::find_sid(vmsym) == i, "1-1 mapping");
+      ciSymbol* sym = new (_arena) ciSymbol(vmsym, (vmSymbols::SID) i);
       init_ident_of(sym);
       _shared_ci_symbols[i] = sym;
     }
 #ifdef ASSERT
     for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {
-      symbolHandle sym_handle = vmSymbolHandles::symbol_handle_at((vmSymbols::SID) i);
+      Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);
       ciSymbol* sym = vm_symbol_at((vmSymbols::SID) i);
-      assert(sym->get_oop() == sym_handle(), "oop must match");
+      assert(sym->get_symbol() == vmsym, "oop must match");
     }
-    assert(ciSymbol::void_class_signature()->get_oop() == vmSymbols::void_class_signature(), "spot check");
+    assert(ciSymbol::void_class_signature()->get_symbol() == vmSymbols::void_class_signature(), "spot check");
 #endif
   }
 
@@ -157,8 +158,6 @@ void ciObjectFactory::init_shared_objects() {
   init_ident_of(ciEnv::_null_object_instance);
   ciEnv::_method_klass_instance =
     get(Universe::methodKlassObj())->as_method_klass();
-  ciEnv::_symbol_klass_instance =
-    get(Universe::symbolKlassObj())->as_symbol_klass();
   ciEnv::_klass_klass_instance =
     get(Universe::klassKlassObj())->as_klass_klass();
   ciEnv::_instance_klass_klass_instance =
@@ -188,7 +187,7 @@ void ciObjectFactory::init_shared_objects() {
     }
   }
 
-  ciEnv::_unloaded_cisymbol = (ciSymbol*) ciObjectFactory::get(vmSymbols::dummy_symbol_oop());
+  ciEnv::_unloaded_cisymbol = ciObjectFactory::get_symbol(vmSymbols::dummy_symbol());
   // Create dummy instanceKlass and objArrayKlass object and assign them idents
   ciEnv::_unloaded_ciinstance_klass = new (_arena) ciInstanceKlass(ciEnv::_unloaded_cisymbol, NULL, NULL);
   init_ident_of(ciEnv::_unloaded_ciinstance_klass);
@@ -218,6 +217,30 @@ void ciObjectFactory::init_shared_objects() {
   _shared_ci_objects = _ci_objects;
 }
 
+
+ciSymbol* ciObjectFactory::get_symbol(Symbol* key) {
+  vmSymbols::SID sid = vmSymbols::find_sid(key);
+  if (sid != vmSymbols::NO_SID) {
+    // do not pollute the main cache with it
+    return vm_symbol_at(sid);
+  }
+
+  assert(vmSymbols::find_sid(key) == vmSymbols::NO_SID, "");
+  ciSymbol* s = new (arena()) ciSymbol(key, vmSymbols::NO_SID);
+  _symbols->push(s);
+  return s;
+}
+
+// Decrement the refcount when done on symbols referenced by this compilation.
+void ciObjectFactory::remove_symbols() {
+  for (int i = 0; i < _symbols->length(); i++) {
+    ciSymbol* s = _symbols->at(i);
+    s->get_symbol()->decrement_refcount();
+  }
+  // Since _symbols is resource allocated we're not allowed to delete it
+  // but it'll go away just the same.
+}
+
 // ------------------------------------------------------------------
 // ciObjectFactory::get
 //
@@ -255,15 +278,6 @@ ciObject* ciObjectFactory::get(oop key) {
       return bucket->object();
     }
 
-    // Check in the shared symbol area before putting it in the list.
-    if (key->is_symbol()) {
-      vmSymbols::SID sid = vmSymbols::find_sid((symbolOop)key);
-      if (sid != vmSymbols::NO_SID) {
-        // do not pollute the main cache with it
-        return vm_symbol_at(sid);
-      }
-    }
-
     // The ciObject does not yet exist.  Create it and insert it
     // into the cache.
     Handle keyHandle(key);
@@ -297,11 +311,7 @@ ciObject* ciObjectFactory::get(oop key) {
 ciObject* ciObjectFactory::create_new_object(oop o) {
   EXCEPTION_CONTEXT;
 
-  if (o->is_symbol()) {
-    symbolHandle h_o(THREAD, (symbolOop)o);
-    assert(vmSymbols::find_sid(h_o()) == vmSymbols::NO_SID, "");
-    return new (arena()) ciSymbol(h_o, vmSymbols::NO_SID);
-  } else if (o->is_klass()) {
+  if (o->is_klass()) {
     KlassHandle h_k(THREAD, (klassOop)o);
     Klass* k = ((klassOop)o)->klass_part();
     if (k->oop_is_instance()) {
@@ -312,8 +322,6 @@ ciObject* ciObjectFactory::create_new_object(oop o) {
       return new (arena()) ciTypeArrayKlass(h_k);
     } else if (k->oop_is_method()) {
       return new (arena()) ciMethodKlass(h_k);
-    } else if (k->oop_is_symbol()) {
-      return new (arena()) ciSymbolKlass(h_k);
     } else if (k->oop_is_klass()) {
       if (k->oop_is_objArrayKlass()) {
         return new (arena()) ciObjArrayKlassKlass(h_k);
@@ -426,22 +434,20 @@ ciKlass* ciObjectFactory::get_unloaded_klass(ciKlass* accessing_klass,
   // unloaded instanceKlass.  Deal with both.
   if (name->byte_at(0) == '[') {
     // Decompose the name.'
-    jint dimension = 0;
-    symbolOop element_name = NULL;
-    BasicType element_type= FieldType::get_array_info(name->get_symbolOop(),
-                                                      &dimension,
-                                                      &element_name,
-                                                      THREAD);
+    FieldArrayInfo fd;
+    BasicType element_type = FieldType::get_array_info(name->get_symbol(),
+                                                       fd, THREAD);
     if (HAS_PENDING_EXCEPTION) {
       CLEAR_PENDING_EXCEPTION;
       CURRENT_THREAD_ENV->record_out_of_memory_failure();
       return ciEnv::_unloaded_ciobjarrayklass;
     }
+    int dimension = fd.dimension();
     assert(element_type != T_ARRAY, "unsuccessful decomposition");
     ciKlass* element_klass = NULL;
     if (element_type == T_OBJECT) {
       ciEnv *env = CURRENT_THREAD_ENV;
-      ciSymbol* ci_name = env->get_object(element_name)->as_symbol();
+      ciSymbol* ci_name = env->get_symbol(fd.object_key());
       element_klass =
         env->get_klass_by_name(accessing_klass, ci_name, false)->as_instance_klass();
     } else {
@@ -573,6 +579,10 @@ void ciObjectFactory::init_ident_of(ciObject* obj) {
   obj->set_ident(_next_ident++);
 }
 
+void ciObjectFactory::init_ident_of(ciSymbol* obj) {
+  obj->set_ident(_next_ident++);
+}
+
 
 // ------------------------------------------------------------------
 // ciObjectFactory::find

src/share/vm/ci/ciObjectFactory.hpp

@@ -48,6 +48,7 @@ private:
   GrowableArray<ciKlass*>* _unloaded_klasses;
   GrowableArray<ciInstance*>* _unloaded_instances;
   GrowableArray<ciReturnAddress*>* _return_addresses;
+  GrowableArray<ciSymbol*>* _symbols;  // keep list of symbols created
   int                       _next_ident;
 
 public:
@@ -76,6 +77,7 @@ private:
   void insert_non_perm(NonPermObject* &where, oop key, ciObject* obj);
 
   void init_ident_of(ciObject* obj);
+  void init_ident_of(ciSymbol* obj);
 
   Arena* arena() { return _arena; }
 
@@ -88,13 +90,15 @@ public:
 
   static void initialize();
   void init_shared_objects();
+  void remove_symbols();
 
   ciObjectFactory(Arena* arena, int expected_size);
 
-
   // Get the ciObject corresponding to some oop.
   ciObject* get(oop key);
 
+  ciSymbol* get_symbol(Symbol* key);
+
   // Get the ciSymbol corresponding to one of the vmSymbols.
   static ciSymbol* vm_symbol_at(int index);
 

src/share/vm/ci/ciSignature.cpp

@@ -47,7 +47,8 @@ ciSignature::ciSignature(ciKlass* accessing_klass, ciSymbol* symbol) {
 
   int size = 0;
   int count = 0;
-  symbolHandle sh (THREAD, symbol->get_symbolOop());
+  ResourceMark rm(THREAD);
+  Symbol* sh = symbol->get_symbol();
   SignatureStream ss(sh);
   for (; ; ss.next()) {
     // Process one element of the signature
@@ -55,14 +56,14 @@ ciSignature::ciSignature(ciKlass* accessing_klass, ciSymbol* symbol) {
     if (!ss.is_object()) {
       type = ciType::make(ss.type());
     } else {
-      symbolOop name = ss.as_symbol(THREAD);
+      Symbol* name = ss.as_symbol(THREAD);
       if (HAS_PENDING_EXCEPTION) {
         type = ss.is_array() ? (ciType*)ciEnv::unloaded_ciobjarrayklass()
           : (ciType*)ciEnv::unloaded_ciinstance_klass();
         env->record_out_of_memory_failure();
         CLEAR_PENDING_EXCEPTION;
       } else {
-        ciSymbol* klass_name = env->get_object(name)->as_symbol();
+        ciSymbol* klass_name = env->get_symbol(name);
         type = env->get_klass_by_name_impl(_accessing_klass, klass_name, false);
       }
     }

src/share/vm/ci/ciSignature.hpp

@@ -48,7 +48,7 @@ private:
 
   void get_all_klasses();
 
-  symbolOop get_symbolOop() const                { return _symbol->get_symbolOop(); }
+  Symbol* get_symbol() const                     { return _symbol->get_symbol(); }
 
 public:
   ciSymbol* as_symbol() const                    { return _symbol; }

src/share/vm/ci/ciSymbol.cpp

@@ -30,23 +30,27 @@
 // ------------------------------------------------------------------
 // ciSymbol::ciSymbol
 //
-// Preallocated handle variant.  Used with handles from vmSymboHandles.
-ciSymbol::ciSymbol(symbolHandle h_s, vmSymbols::SID sid)
-  : ciObject(h_s), _sid(sid)
+// Preallocated symbol variant.  Used with symbols from vmSymbols.
+ciSymbol::ciSymbol(Symbol* s, vmSymbols::SID sid)
+  : _symbol(s), _sid(sid)
 {
+  assert(_symbol != NULL, "adding null symbol");
+  _symbol->increment_refcount();  // increment ref count
   assert(sid_ok(), "must be in vmSymbols");
 }
 
 // Normal case for non-famous symbols.
-ciSymbol::ciSymbol(symbolOop s)
-  : ciObject(s), _sid(vmSymbols::NO_SID)
+ciSymbol::ciSymbol(Symbol* s)
+  : _symbol(s), _sid(vmSymbols::NO_SID)
 {
+  assert(_symbol != NULL, "adding null symbol");
+  _symbol->increment_refcount();  // increment ref count
   assert(sid_ok(), "must not be in vmSymbols");
 }
 
 // ciSymbol
 //
-// This class represents a symbolOop in the HotSpot virtual
+// This class represents a Symbol* in the HotSpot virtual
 // machine.
 
 // ------------------------------------------------------------------
@@ -55,20 +59,20 @@ ciSymbol::ciSymbol(symbolOop s)
 // The text of the symbol as a null-terminated C string.
 const char* ciSymbol::as_utf8() {
   VM_QUICK_ENTRY_MARK;
-  symbolOop s = get_symbolOop();
+  Symbol* s = get_symbol();
   return s->as_utf8();
 }
 
 // ------------------------------------------------------------------
 // ciSymbol::base
-jbyte* ciSymbol::base() {
-  GUARDED_VM_ENTRY(return get_symbolOop()->base();)
+const jbyte* ciSymbol::base() {
+  GUARDED_VM_ENTRY(return get_symbol()->base();)
 }
 
 // ------------------------------------------------------------------
 // ciSymbol::byte_at
 int ciSymbol::byte_at(int i) {
-  GUARDED_VM_ENTRY(return get_symbolOop()->byte_at(i);)
+  GUARDED_VM_ENTRY(return get_symbol()->byte_at(i);)
 }
 
 // ------------------------------------------------------------------
@@ -76,7 +80,7 @@ int ciSymbol::byte_at(int i) {
 //
 // Tests if the symbol starts with the given prefix.
 bool ciSymbol::starts_with(const char* prefix, int len) const {
-  GUARDED_VM_ENTRY(return get_symbolOop()->starts_with(prefix, len);)
+  GUARDED_VM_ENTRY(return get_symbol()->starts_with(prefix, len);)
 }
 
 // ------------------------------------------------------------------
@@ -84,13 +88,13 @@ bool ciSymbol::starts_with(const char* prefix, int len) const {
 //
 // Determines where the symbol contains the given substring.
 int ciSymbol::index_of_at(int i, const char* str, int len) const {
-  GUARDED_VM_ENTRY(return get_symbolOop()->index_of_at(i, str, len);)
+  GUARDED_VM_ENTRY(return get_symbol()->index_of_at(i, str, len);)
 }
 
 // ------------------------------------------------------------------
 // ciSymbol::utf8_length
 int ciSymbol::utf8_length() {
-  GUARDED_VM_ENTRY(return get_symbolOop()->utf8_length();)
+  GUARDED_VM_ENTRY(return get_symbol()->utf8_length();)
 }
 
 // ------------------------------------------------------------------
@@ -107,7 +111,7 @@ void ciSymbol::print_impl(outputStream* st) {
 //
 // Print the value of this symbol on an outputStream
 void ciSymbol::print_symbol_on(outputStream *st) {
-  GUARDED_VM_ENTRY(get_symbolOop()->print_symbol_on(st);)
+  GUARDED_VM_ENTRY(get_symbol()->print_symbol_on(st);)
 }
 
 // ------------------------------------------------------------------
@@ -116,15 +120,13 @@ void ciSymbol::print_symbol_on(outputStream *st) {
 // Make a ciSymbol from a C string (implementation).
 ciSymbol* ciSymbol::make_impl(const char* s) {
   EXCEPTION_CONTEXT;
-  // For some reason, oopFactory::new_symbol doesn't declare its
-  // char* argument as const.
-  symbolOop sym = oopFactory::new_symbol((char*)s, (int)strlen(s), THREAD);
+  TempNewSymbol sym = SymbolTable::new_symbol(s, THREAD);
   if (HAS_PENDING_EXCEPTION) {
     CLEAR_PENDING_EXCEPTION;
     CURRENT_THREAD_ENV->record_out_of_memory_failure();
     return ciEnv::_unloaded_cisymbol;
   }
-  return CURRENT_THREAD_ENV->get_object(sym)->as_symbol();
+  return CURRENT_THREAD_ENV->get_symbol(sym);
 }
 
 // ------------------------------------------------------------------

src/share/vm/ci/ciSymbol.hpp

@@ -28,15 +28,18 @@
 #include "ci/ciObject.hpp"
 #include "ci/ciObjectFactory.hpp"
 #include "classfile/vmSymbols.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 
 // ciSymbol
 //
-// This class represents a symbolOop in the HotSpot virtual
+// This class represents a Symbol* in the HotSpot virtual
 // machine.
-class ciSymbol : public ciObject {
+class ciSymbol : public ResourceObj {
+  Symbol* _symbol;
+  uint _ident;
+
   CI_PACKAGE_ACCESS
-  // These friends all make direct use of get_symbolOop:
+  // These friends all make direct use of get_symbol:
   friend class ciEnv;
   friend class ciInstanceKlass;
   friend class ciSignature;
@@ -45,24 +48,28 @@ class ciSymbol : public ciObject {
 
 private:
   const vmSymbols::SID _sid;
-  DEBUG_ONLY( bool sid_ok() { return vmSymbols::find_sid(get_symbolOop()) == _sid; } )
+  DEBUG_ONLY( bool sid_ok() { return vmSymbols::find_sid(get_symbol()) == _sid; } )
 
-  ciSymbol(symbolOop s);  // normal case, for symbols not mentioned in vmSymbols
-  ciSymbol(symbolHandle s, vmSymbols::SID sid);   // for use with vmSymbolHandles
+  ciSymbol(Symbol* s);  // normal case, for symbols not mentioned in vmSymbols
+  ciSymbol(Symbol* s, vmSymbols::SID sid);   // for use with vmSymbols
 
-  symbolOop get_symbolOop() const { return (symbolOop)get_oop(); }
+  Symbol* get_symbol() const { return _symbol; }
 
   const char* type_string() { return "ciSymbol"; }
 
   void print_impl(outputStream* st);
 
-  // This is public in symbolOop but private here, because the base can move:
-  jbyte*      base();
+  // This is public in Symbol* but private here, because the base can move:
+  const jbyte* base();
 
   // Make a ciSymbol from a C string (implementation).
   static ciSymbol* make_impl(const char* s);
 
+  void set_ident(uint id) { _ident = id; }
 public:
+  // A number unique to this object.
+  uint ident() { return _ident; }
+
   // The enumeration ID from vmSymbols, or vmSymbols::NO_SID if none.
   vmSymbols::SID sid() const { return _sid; }
 
@@ -79,9 +86,6 @@ public:
   // Determines where the symbol contains the given substring.
   int index_of_at(int i, const char* str, int len) const;
 
-  // What kind of ciObject is this?
-  bool is_symbol() { return true; }
-
   void print_symbol_on(outputStream* st);
   void print_symbol() {
     print_symbol_on(tty);
@@ -96,6 +100,13 @@ public:
   static ciSymbol* name() { return ciObjectFactory::vm_symbol_at(vmSymbols::VM_SYMBOL_ENUM_NAME(name)); }
   VM_SYMBOLS_DO(CI_SYMBOL_DECLARE, CI_SYMBOL_DECLARE)
 #undef CI_SYMBOL_DECLARE
+
+  void print() {
+    _symbol->print();
+  }
+
+  // Are two ciSymbols equal?
+  bool equals(ciSymbol* obj) { return this->_symbol == obj->get_symbol(); }
 };
 
 #endif // SHARE_VM_CI_CISYMBOL_HPP

src/share/vm/ci/ciSymbolKlass.cpp

-/*
- * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#include "precompiled.hpp"
-#include "ci/ciSymbolKlass.hpp"
-#include "ci/ciUtilities.hpp"
-
-// ciSymbolKlass
-//
-// This class represents a klassOop in the HotSpot virtual machine
-// whose Klass part is a symbolKlass.
-
-// ------------------------------------------------------------------
-// ciSymbolKlass::instance
-//
-// Return the distinguished instance of this class
-ciSymbolKlass* ciSymbolKlass::make() {
-  return CURRENT_ENV->_symbol_klass_instance;
-}

src/share/vm/ci/ciSymbolKlass.hpp

-/*
- * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#ifndef SHARE_VM_CI_CISYMBOLKLASS_HPP
-#define SHARE_VM_CI_CISYMBOLKLASS_HPP
-
-#include "ci/ciKlass.hpp"
-#include "ci/ciSymbol.hpp"
-
-// ciSymbolKlass
-//
-// This class represents a klassOop in the HotSpot virtual machine
-// whose Klass part in a symbolKlass.  Although, in the VM
-// Klass hierarchy, symbolKlass is a direct subclass of typeArrayKlass,
-// we do not model this relationship in the ciObject hierarchy -- the
-// subclassing is used to share implementation and is not of note
-// to compiler writers.
-class ciSymbolKlass : public ciKlass {
-  CI_PACKAGE_ACCESS
-
-protected:
-  ciSymbolKlass(KlassHandle h_k)
-    : ciKlass(h_k, ciSymbol::make("unique_symbolKlass")) {
-    assert(get_Klass()->oop_is_symbol(), "wrong type");
-  }
-
-  symbolKlass* get_symbolKlass() { return (symbolKlass*)get_Klass(); }
-
-  const char* type_string() { return "ciSymbolKlass"; }
-
-public:
-  // What kind of ciObject is this?
-  bool is_symbol_klass() { return true; }
-
-  // Return the distinguished ciSymbolKlass instance.
-  static ciSymbolKlass* make();
-};
-
-#endif // SHARE_VM_CI_CISYMBOLKLASS_HPP

src/share/vm/ci/compilerInterface.hpp

@@ -49,7 +49,6 @@
 #include "ci/ciSignature.hpp"
 #include "ci/ciStreams.hpp"
 #include "ci/ciSymbol.hpp"
-#include "ci/ciSymbolKlass.hpp"
 #include "ci/ciTypeArray.hpp"
 #include "ci/ciTypeArrayKlass.hpp"
 #include "ci/ciTypeArrayKlassKlass.hpp"

src/share/vm/classfile/classFileError.cpp

@@ -31,25 +31,25 @@
 
 void ClassFileParser::classfile_parse_error(const char* msg, TRAPS) {
     ResourceMark rm(THREAD);
-    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbolHandles::java_lang_ClassFormatError(),
+    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_ClassFormatError(),
                        msg, _class_name->as_C_string());
 }
 
 void ClassFileParser::classfile_parse_error(const char* msg, int index, TRAPS) {
     ResourceMark rm(THREAD);
-    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbolHandles::java_lang_ClassFormatError(),
+    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_ClassFormatError(),
                        msg, index, _class_name->as_C_string());
 }
 
 void ClassFileParser::classfile_parse_error(const char* msg, const char *name, TRAPS) {
     ResourceMark rm(THREAD);
-    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbolHandles::java_lang_ClassFormatError(),
+    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_ClassFormatError(),
                        msg, name, _class_name->as_C_string());
 }
 
 void ClassFileParser::classfile_parse_error(const char* msg, int index, const char *name, TRAPS) {
     ResourceMark rm(THREAD);
-    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbolHandles::java_lang_ClassFormatError(),
+    Exceptions::fthrow(THREAD_AND_LOCATION, vmSymbols::java_lang_ClassFormatError(),
                        msg, index, name, _class_name->as_C_string());
 }
 
@@ -57,7 +57,7 @@ void StackMapStream::stackmap_format_error(const char* msg, TRAPS) {
   ResourceMark rm(THREAD);
   Exceptions::fthrow(
     THREAD_AND_LOCATION,
-    vmSymbolHandles::java_lang_ClassFormatError(),
+    vmSymbols::java_lang_ClassFormatError(),
     "StackMapTable format error: %s", msg
   );
 }

src/share/vm/classfile/classFileParser.hpp

@@ -32,6 +32,7 @@
 #include "runtime/handles.inline.hpp"
 #include "utilities/accessFlags.hpp"
 
+class TempNewSymbol;
 // Parser for for .class files
 //
 // The bytes describing the class file structure is read from a Stream object
@@ -42,7 +43,7 @@ class ClassFileParser VALUE_OBJ_CLASS_SPEC {
   bool _relax_verify;
   u2   _major_version;
   u2   _minor_version;
-  symbolHandle _class_name;
+  Symbol* _class_name;
   KlassHandle _host_klass;
   GrowableArray<Handle>* _cp_patches; // overrides for CP entries
 
@@ -73,7 +74,7 @@ class ClassFileParser VALUE_OBJ_CLASS_SPEC {
                                   int length,
                                   Handle class_loader,
                                   Handle protection_domain,
-                                  symbolHandle class_name,
+                                  Symbol* class_name,
                                   TRAPS);
 
   // Field parsing
@@ -209,21 +210,21 @@ class ClassFileParser VALUE_OBJ_CLASS_SPEC {
   }
 
   void throwIllegalSignature(
-      const char* type, symbolHandle name, symbolHandle sig, TRAPS);
+      const char* type, Symbol* name, Symbol* sig, TRAPS);
 
   bool is_supported_version(u2 major, u2 minor);
   bool has_illegal_visibility(jint flags);
 
   void verify_constantvalue(int constantvalue_index, int signature_index, constantPoolHandle cp, TRAPS);
   void verify_legal_utf8(const unsigned char* buffer, int length, TRAPS);
-  void verify_legal_class_name(symbolHandle name, TRAPS);
-  void verify_legal_field_name(symbolHandle name, TRAPS);
-  void verify_legal_method_name(symbolHandle name, TRAPS);
-  void verify_legal_field_signature(symbolHandle fieldname, symbolHandle signature, TRAPS);
-  int  verify_legal_method_signature(symbolHandle methodname, symbolHandle signature, TRAPS);
+  void verify_legal_class_name(Symbol* name, TRAPS);
+  void verify_legal_field_name(Symbol* name, TRAPS);
+  void verify_legal_method_name(Symbol* name, TRAPS);
+  void verify_legal_field_signature(Symbol* fieldname, Symbol* signature, TRAPS);
+  int  verify_legal_method_signature(Symbol* methodname, Symbol* signature, TRAPS);
   void verify_legal_class_modifiers(jint flags, TRAPS);
   void verify_legal_field_modifiers(jint flags, bool is_interface, TRAPS);
-  void verify_legal_method_modifiers(jint flags, bool is_interface, symbolHandle name, TRAPS);
+  void verify_legal_method_modifiers(jint flags, bool is_interface, Symbol* name, TRAPS);
   bool verify_unqualified_name(char* name, unsigned int length, int type);
   char* skip_over_field_name(char* name, bool slash_ok, unsigned int length);
   char* skip_over_field_signature(char* signature, bool void_ok, unsigned int length, TRAPS);
@@ -272,21 +273,21 @@ class ClassFileParser VALUE_OBJ_CLASS_SPEC {
   //
   // "parsed_name" is updated by this method, and is the name found
   // while parsing the stream.
-  instanceKlassHandle parseClassFile(symbolHandle name,
+  instanceKlassHandle parseClassFile(Symbol* name,
                                      Handle class_loader,
                                      Handle protection_domain,
-                                     symbolHandle& parsed_name,
+                                     TempNewSymbol& parsed_name,
                                      bool verify,
                                      TRAPS) {
     KlassHandle no_host_klass;
     return parseClassFile(name, class_loader, protection_domain, no_host_klass, NULL, parsed_name, verify, THREAD);
   }
-  instanceKlassHandle parseClassFile(symbolHandle name,
+  instanceKlassHandle parseClassFile(Symbol* name,
                                      Handle class_loader,
                                      Handle protection_domain,
                                      KlassHandle host_klass,
                                      GrowableArray<Handle>* cp_patches,
-                                     symbolHandle& parsed_name,
+                                     TempNewSymbol& parsed_name,
                                      bool verify,
                                      TRAPS);
 

src/share/vm/classfile/classLoader.cpp

@@ -41,7 +41,7 @@
 #include "oops/instanceKlass.hpp"
 #include "oops/instanceRefKlass.hpp"
 #include "oops/oop.inline.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "prims/jvm_misc.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/compilationPolicy.hpp"
@@ -752,11 +752,7 @@ void PackageHashtable::copy_table(char** top, char* end,
     }
   }
   if (*top + n + sizeof(intptr_t) >= end) {
-    warning("\nThe shared miscellaneous data space is not large "
-            "enough to \npreload requested classes.  Use "
-            "-XX:SharedMiscDataSize= to increase \nthe initial "
-            "size of the miscellaneous data space.\n");
-    exit(2);
+    report_out_of_shared_space(SharedMiscData);
   }
 
   // Copy the table data (the strings) to the shared space.
@@ -875,9 +871,9 @@ objArrayOop ClassLoader::get_system_packages(TRAPS) {
 }
 
 
-instanceKlassHandle ClassLoader::load_classfile(symbolHandle h_name, TRAPS) {
+instanceKlassHandle ClassLoader::load_classfile(Symbol* h_name, TRAPS) {
   ResourceMark rm(THREAD);
-  EventMark m("loading class " INTPTR_FORMAT, (address)h_name());
+  EventMark m("loading class " INTPTR_FORMAT, (address)h_name);
   ThreadProfilerMark tpm(ThreadProfilerMark::classLoaderRegion);
 
   stringStream st;
@@ -912,7 +908,7 @@ instanceKlassHandle ClassLoader::load_classfile(symbolHandle h_name, TRAPS) {
     ClassFileParser parser(stream);
     Handle class_loader;
     Handle protection_domain;
-    symbolHandle parsed_name;
+    TempNewSymbol parsed_name = NULL;
     instanceKlassHandle result = parser.parseClassFile(h_name,
                                                        class_loader,
                                                        protection_domain,
@@ -1308,7 +1304,7 @@ void ClassLoader::compile_the_world_in(char* name, Handle loader, TRAPS) {
       if (_compile_the_world_counter > CompileTheWorldStopAt) return;
 
       // Construct name without extension
-      symbolHandle sym = oopFactory::new_symbol_handle(buffer, CHECK);
+      TempNewSymbol sym = SymbolTable::new_symbol(buffer, CHECK);
       // Use loader to load and initialize class
       klassOop ik = SystemDictionary::resolve_or_null(sym, loader, Handle(), THREAD);
       instanceKlassHandle k (THREAD, ik);

src/share/vm/classfile/classLoader.hpp

@@ -280,7 +280,7 @@ class ClassLoader: AllStatic {
   }
 
   // Load individual .class file
-  static instanceKlassHandle load_classfile(symbolHandle h_name, TRAPS);
+  static instanceKlassHandle load_classfile(Symbol* h_name, TRAPS);
 
   // If the specified package has been loaded by the system, then returns
   // the name of the directory or ZIP file that the package was loaded from.

src/share/vm/classfile/dictionary.cpp

@@ -36,7 +36,7 @@ int               Dictionary::_current_class_index =    0;
 
 
 Dictionary::Dictionary(int table_size)
-  : TwoOopHashtable(table_size, sizeof(DictionaryEntry)) {
+  : TwoOopHashtable<klassOop>(table_size, sizeof(DictionaryEntry)) {
   _current_class_index = 0;
   _current_class_entry = NULL;
 };
@@ -45,7 +45,7 @@ Dictionary::Dictionary(int table_size)
 
 Dictionary::Dictionary(int table_size, HashtableBucket* t,
                        int number_of_entries)
-  : TwoOopHashtable(table_size, sizeof(DictionaryEntry), t, number_of_entries) {
+  : TwoOopHashtable<klassOop>(table_size, sizeof(DictionaryEntry), t, number_of_entries) {
   _current_class_index = 0;
   _current_class_entry = NULL;
 };
@@ -54,7 +54,7 @@ Dictionary::Dictionary(int table_size, HashtableBucket* t,
 DictionaryEntry* Dictionary::new_entry(unsigned int hash, klassOop klass,
                                        oop loader) {
   DictionaryEntry* entry;
-  entry = (DictionaryEntry*)Hashtable::new_entry(hash, klass);
+  entry = (DictionaryEntry*)Hashtable<klassOop>::new_entry(hash, klass);
   entry->set_loader(loader);
   entry->set_pd_set(NULL);
   return entry;
@@ -62,7 +62,7 @@ DictionaryEntry* Dictionary::new_entry(unsigned int hash, klassOop klass,
 
 
 DictionaryEntry* Dictionary::new_entry() {
-  DictionaryEntry* entry = (DictionaryEntry*)Hashtable::new_entry(0L, NULL);
+  DictionaryEntry* entry = (DictionaryEntry*)Hashtable<klassOop>::new_entry(0L, NULL);
   entry->set_loader(NULL);
   entry->set_pd_set(NULL);
   return entry;
@@ -76,7 +76,7 @@ void Dictionary::free_entry(DictionaryEntry* entry) {
     entry->set_pd_set(to_delete->next());
     delete to_delete;
   }
-  Hashtable::free_entry(entry);
+  Hashtable<klassOop>::free_entry(entry);
 }
 
 
@@ -298,7 +298,7 @@ void Dictionary::always_strong_classes_do(OopClosure* blk) {
     for (DictionaryEntry *probe = bucket(index);
                           probe != NULL;
                           probe = probe->next()) {
-      oop e = probe->klass();
+      klassOop e = probe->klass();
       oop class_loader = probe->loader();
       if (is_strongly_reachable(class_loader, e)) {
         blk->do_oop((oop*)probe->klass_addr());
@@ -421,11 +421,11 @@ klassOop Dictionary::try_get_next_class() {
 // also cast to volatile;  we do this to ensure store order is maintained
 // by the compilers.
 
-void Dictionary::add_klass(symbolHandle class_name, Handle class_loader,
+void Dictionary::add_klass(Symbol* class_name, Handle class_loader,
                            KlassHandle obj) {
   assert_locked_or_safepoint(SystemDictionary_lock);
   assert(obj() != NULL, "adding NULL obj");
-  assert(Klass::cast(obj())->name() == class_name(), "sanity check on name");
+  assert(Klass::cast(obj())->name() == class_name, "sanity check on name");
 
   unsigned int hash = compute_hash(class_name, class_loader);
   int index = hash_to_index(hash);
@@ -444,15 +444,14 @@ void Dictionary::add_klass(symbolHandle class_name, Handle class_loader,
 // Callers should be aware that an entry could be added just after
 // _buckets[index] is read here, so the caller will not see the new entry.
 DictionaryEntry* Dictionary::get_entry(int index, unsigned int hash,
-                                       symbolHandle class_name,
+                                       Symbol* class_name,
                                        Handle class_loader) {
-  symbolOop name_ = class_name();
-  oop loader_ = class_loader();
+  oop loader = class_loader();
   debug_only(_lookup_count++);
   for (DictionaryEntry* entry = bucket(index);
                         entry != NULL;
                         entry = entry->next()) {
-    if (entry->hash() == hash && entry->equals(name_, loader_)) {
+    if (entry->hash() == hash && entry->equals(class_name, loader)) {
       return entry;
     }
     debug_only(_lookup_length++);
@@ -461,7 +460,7 @@ DictionaryEntry* Dictionary::get_entry(int index, unsigned int hash,
 }
 
 
-klassOop Dictionary::find(int index, unsigned int hash, symbolHandle name,
+klassOop Dictionary::find(int index, unsigned int hash, Symbol* name,
                           Handle loader, Handle protection_domain, TRAPS) {
   DictionaryEntry* entry = get_entry(index, hash, name, loader);
   if (entry != NULL && entry->is_valid_protection_domain(protection_domain)) {
@@ -473,7 +472,7 @@ klassOop Dictionary::find(int index, unsigned int hash, symbolHandle name,
 
 
 klassOop Dictionary::find_class(int index, unsigned int hash,
-                                symbolHandle name, Handle loader) {
+                                Symbol* name, Handle loader) {
   assert_locked_or_safepoint(SystemDictionary_lock);
   assert (index == index_for(name, loader), "incorrect index?");
 
@@ -486,7 +485,7 @@ klassOop Dictionary::find_class(int index, unsigned int hash,
 // that table is static.
 
 klassOop Dictionary::find_shared_class(int index, unsigned int hash,
-                                       symbolHandle name) {
+                                       Symbol* name) {
   assert (index == index_for(name, Handle()), "incorrect index?");
 
   DictionaryEntry* entry = get_entry(index, hash, name, Handle());
@@ -498,7 +497,7 @@ void Dictionary::add_protection_domain(int index, unsigned int hash,
                                        instanceKlassHandle klass,
                                        Handle loader, Handle protection_domain,
                                        TRAPS) {
-  symbolHandle klass_name(THREAD, klass->name());
+  Symbol*  klass_name = klass->name();
   DictionaryEntry* entry = get_entry(index, hash, klass_name, loader);
 
   assert(entry != NULL,"entry must be present, we just created it");
@@ -513,7 +512,7 @@ void Dictionary::add_protection_domain(int index, unsigned int hash,
 
 
 bool Dictionary::is_valid_protection_domain(int index, unsigned int hash,
-                                            symbolHandle name,
+                                            Symbol* name,
                                             Handle loader,
                                             Handle protection_domain) {
   DictionaryEntry* entry = get_entry(index, hash, name, loader);
@@ -545,7 +544,7 @@ void Dictionary::reorder_dictionary() {
     DictionaryEntry* p = master_list;
     master_list = master_list->next();
     p->set_next(NULL);
-    symbolHandle class_name (thread, instanceKlass::cast((klassOop)(p->klass()))->name());
+    Symbol* class_name = instanceKlass::cast((klassOop)(p->klass()))->name();
     unsigned int hash = compute_hash(class_name, Handle(thread, p->loader()));
     int index = hash_to_index(hash);
     p->set_hash(hash);
@@ -555,22 +554,22 @@ void Dictionary::reorder_dictionary() {
 }
 
 SymbolPropertyTable::SymbolPropertyTable(int table_size)
-  : Hashtable(table_size, sizeof(SymbolPropertyEntry))
+  : Hashtable<Symbol*>(table_size, sizeof(SymbolPropertyEntry))
 {
 }
 SymbolPropertyTable::SymbolPropertyTable(int table_size, HashtableBucket* t,
                                          int number_of_entries)
-  : Hashtable(table_size, sizeof(SymbolPropertyEntry), t, number_of_entries)
+  : Hashtable<Symbol*>(table_size, sizeof(SymbolPropertyEntry), t, number_of_entries)
 {
 }
 
 
 SymbolPropertyEntry* SymbolPropertyTable::find_entry(int index, unsigned int hash,
-                                                     symbolHandle sym,
+                                                     Symbol* sym,
                                                      intptr_t sym_mode) {
   assert(index == index_for(sym, sym_mode), "incorrect index?");
   for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) {
-    if (p->hash() == hash && p->symbol() == sym() && p->symbol_mode() == sym_mode) {
+    if (p->hash() == hash && p->symbol() == sym && p->symbol_mode() == sym_mode) {
       return p;
     }
   }
@@ -579,13 +578,13 @@ SymbolPropertyEntry* SymbolPropertyTable::find_entry(int index, unsigned int has
 
 
 SymbolPropertyEntry* SymbolPropertyTable::add_entry(int index, unsigned int hash,
-                                                    symbolHandle sym, intptr_t sym_mode) {
+                                                    Symbol* sym, intptr_t sym_mode) {
   assert_locked_or_safepoint(SystemDictionary_lock);
   assert(index == index_for(sym, sym_mode), "incorrect index?");
   assert(find_entry(index, hash, sym, sym_mode) == NULL, "no double entry");
 
-  SymbolPropertyEntry* p = new_entry(hash, sym(), sym_mode);
-  Hashtable::add_entry(index, p);
+  SymbolPropertyEntry* p = new_entry(hash, sym, sym_mode);
+  Hashtable<Symbol*>::add_entry(index, p);
   return p;
 }
 
@@ -593,7 +592,6 @@ SymbolPropertyEntry* SymbolPropertyTable::add_entry(int index, unsigned int hash
 void SymbolPropertyTable::oops_do(OopClosure* f) {
   for (int index = 0; index < table_size(); index++) {
     for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) {
-      f->do_oop((oop*) p->symbol_addr());
       if (p->property_oop() != NULL) {
         f->do_oop(p->property_oop_addr());
       }

src/share/vm/classfile/dictionary.hpp

@@ -36,7 +36,7 @@ class DictionaryEntry;
 // The data structure for the system dictionary (and the shared system
 // dictionary).
 
-class Dictionary : public TwoOopHashtable {
+class Dictionary : public TwoOopHashtable<klassOop> {
   friend class VMStructs;
 private:
   // current iteration index.
@@ -45,19 +45,19 @@ private:
   static DictionaryEntry*       _current_class_entry;
 
   DictionaryEntry* get_entry(int index, unsigned int hash,
-                             symbolHandle name, Handle loader);
+                             Symbol* name, Handle loader);
 
   DictionaryEntry* bucket(int i) {
-    return (DictionaryEntry*)Hashtable::bucket(i);
+    return (DictionaryEntry*)Hashtable<klassOop>::bucket(i);
   }
 
   // The following method is not MT-safe and must be done under lock.
   DictionaryEntry** bucket_addr(int i) {
-    return (DictionaryEntry**)Hashtable::bucket_addr(i);
+    return (DictionaryEntry**)Hashtable<klassOop>::bucket_addr(i);
   }
 
   void add_entry(int index, DictionaryEntry* new_entry) {
-    Hashtable::add_entry(index, (HashtableEntry*)new_entry);
+    Hashtable<klassOop>::add_entry(index, (HashtableEntry<oop>*)new_entry);
   }
 
 
@@ -71,12 +71,12 @@ public:
 
   void free_entry(DictionaryEntry* entry);
 
-  void add_klass(symbolHandle class_name, Handle class_loader,KlassHandle obj);
+  void add_klass(Symbol* class_name, Handle class_loader,KlassHandle obj);
 
   klassOop find_class(int index, unsigned int hash,
-                      symbolHandle name, Handle loader);
+                      Symbol* name, Handle loader);
 
-  klassOop find_shared_class(int index, unsigned int hash, symbolHandle name);
+  klassOop find_shared_class(int index, unsigned int hash, Symbol* name);
 
   // Compiler support
   klassOop try_get_next_class();
@@ -95,7 +95,7 @@ public:
 
   // Classes loaded by the bootstrap loader are always strongly reachable.
   // If we're not doing class unloading, all classes are strongly reachable.
-  static bool is_strongly_reachable(oop class_loader, oop klass) {
+  static bool is_strongly_reachable(oop class_loader, klassOop klass) {
     assert (klass != NULL, "should have non-null klass");
     return (class_loader == NULL || !ClassUnloading);
   }
@@ -105,10 +105,10 @@ public:
   bool do_unloading(BoolObjectClosure* is_alive);
 
   // Protection domains
-  klassOop find(int index, unsigned int hash, symbolHandle name,
+  klassOop find(int index, unsigned int hash, Symbol* name,
                 Handle loader, Handle protection_domain, TRAPS);
   bool is_valid_protection_domain(int index, unsigned int hash,
-                                  symbolHandle name, Handle class_loader,
+                                  Symbol* name, Handle class_loader,
                                   Handle protection_domain);
   void add_protection_domain(int index, unsigned int hash,
                              instanceKlassHandle klass, Handle loader,
@@ -147,7 +147,7 @@ class ProtectionDomainEntry :public CHeapObj {
 // An entry in the system dictionary, this describes a class as
 // { klassOop, loader, protection_domain }.
 
-class DictionaryEntry : public HashtableEntry {
+class DictionaryEntry : public HashtableEntry<klassOop> {
   friend class VMStructs;
  private:
   // Contains the set of approved protection domains that can access
@@ -166,11 +166,11 @@ class DictionaryEntry : public HashtableEntry {
   klassOop* klass_addr() { return (klassOop*)literal_addr(); }
 
   DictionaryEntry* next() const {
-    return (DictionaryEntry*)HashtableEntry::next();
+    return (DictionaryEntry*)HashtableEntry<klassOop>::next();
   }
 
   DictionaryEntry** next_addr() {
-    return (DictionaryEntry**)HashtableEntry::next_addr();
+    return (DictionaryEntry**)HashtableEntry<klassOop>::next_addr();
   }
 
   oop loader() const { return _loader; }
@@ -209,7 +209,7 @@ class DictionaryEntry : public HashtableEntry {
     }
   }
 
-  bool equals(symbolOop class_name, oop class_loader) const {
+  bool equals(Symbol* class_name, oop class_loader) const {
     klassOop klass = (klassOop)literal();
     return (instanceKlass::cast(klass)->name() == class_name &&
             _loader == class_loader);
@@ -226,9 +226,9 @@ class DictionaryEntry : public HashtableEntry {
   }
 };
 
-// Entry in a SymbolPropertyTable, mapping a single symbolOop
+// Entry in a SymbolPropertyTable, mapping a single Symbol*
 // to a managed and an unmanaged pointer.
-class SymbolPropertyEntry : public HashtableEntry {
+class SymbolPropertyEntry : public HashtableEntry<Symbol*> {
   friend class VMStructs;
  private:
   intptr_t _symbol_mode;  // secondary key
@@ -236,7 +236,7 @@ class SymbolPropertyEntry : public HashtableEntry {
   address _property_data;
 
  public:
-  symbolOop symbol() const          { return (symbolOop) literal(); }
+  Symbol* symbol() const            { return literal(); }
 
   intptr_t symbol_mode() const      { return _symbol_mode; }
   void set_symbol_mode(intptr_t m)  { _symbol_mode = m; }
@@ -248,14 +248,13 @@ class SymbolPropertyEntry : public HashtableEntry {
   void set_property_data(address p) { _property_data = p; }
 
   SymbolPropertyEntry* next() const {
-    return (SymbolPropertyEntry*)HashtableEntry::next();
+    return (SymbolPropertyEntry*)HashtableEntry<Symbol*>::next();
   }
 
   SymbolPropertyEntry** next_addr() {
-    return (SymbolPropertyEntry**)HashtableEntry::next_addr();
+    return (SymbolPropertyEntry**)HashtableEntry<Symbol*>::next_addr();
   }
 
-  oop* symbol_addr()                { return literal_addr(); }
   oop* property_oop_addr()          { return &_property_oop; }
 
   void print_on(outputStream* st) const {
@@ -279,16 +278,16 @@ class SymbolPropertyEntry : public HashtableEntry {
 // A system-internal mapping of symbols to pointers, both managed
 // and unmanaged.  Used to record the auto-generation of each method
 // MethodHandle.invoke(S)T, for all signatures (S)T.
-class SymbolPropertyTable : public Hashtable {
+class SymbolPropertyTable : public Hashtable<Symbol*> {
   friend class VMStructs;
 private:
   SymbolPropertyEntry* bucket(int i) {
-    return (SymbolPropertyEntry*) Hashtable::bucket(i);
+    return (SymbolPropertyEntry*) Hashtable<Symbol*>::bucket(i);
   }
 
   // The following method is not MT-safe and must be done under lock.
   SymbolPropertyEntry** bucket_addr(int i) {
-    return (SymbolPropertyEntry**) Hashtable::bucket_addr(i);
+    return (SymbolPropertyEntry**) Hashtable<Symbol*>::bucket_addr(i);
   }
 
   void add_entry(int index, SymbolPropertyEntry* new_entry) {
@@ -298,8 +297,10 @@ private:
     ShouldNotReachHere();
   }
 
-  SymbolPropertyEntry* new_entry(unsigned int hash, symbolOop symbol, intptr_t symbol_mode) {
-    SymbolPropertyEntry* entry = (SymbolPropertyEntry*) Hashtable::new_entry(hash, symbol);
+  SymbolPropertyEntry* new_entry(unsigned int hash, Symbol* symbol, intptr_t symbol_mode) {
+    SymbolPropertyEntry* entry = (SymbolPropertyEntry*) Hashtable<Symbol*>::new_entry(hash, symbol);
+    // Hashtable with Symbol* literal must increment and decrement refcount.
+    symbol->increment_refcount();
     entry->set_symbol_mode(symbol_mode);
     entry->set_property_oop(NULL);
     entry->set_property_data(NULL);
@@ -311,23 +312,25 @@ public:
   SymbolPropertyTable(int table_size, HashtableBucket* t, int number_of_entries);
 
   void free_entry(SymbolPropertyEntry* entry) {
-    Hashtable::free_entry(entry);
+    // decrement Symbol refcount here because hashtable doesn't.
+    entry->literal()->decrement_refcount();
+    Hashtable<Symbol*>::free_entry(entry);
   }
 
-  unsigned int compute_hash(symbolHandle sym, intptr_t symbol_mode) {
+  unsigned int compute_hash(Symbol* sym, intptr_t symbol_mode) {
     // Use the regular identity_hash.
-    return Hashtable::compute_hash(sym) ^ symbol_mode;
+    return Hashtable<Symbol*>::compute_hash(sym) ^ symbol_mode;
   }
 
-  int index_for(symbolHandle name, intptr_t symbol_mode) {
+  int index_for(Symbol* name, intptr_t symbol_mode) {
     return hash_to_index(compute_hash(name, symbol_mode));
   }
 
   // need not be locked; no state change
-  SymbolPropertyEntry* find_entry(int index, unsigned int hash, symbolHandle name, intptr_t name_mode);
+  SymbolPropertyEntry* find_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode);
 
   // must be done under SystemDictionary_lock
-  SymbolPropertyEntry* add_entry(int index, unsigned int hash, symbolHandle name, intptr_t name_mode);
+  SymbolPropertyEntry* add_entry(int index, unsigned int hash, Symbol* name, intptr_t name_mode);
 
   // GC support
   void oops_do(OopClosure* f);
@@ -343,6 +346,4 @@ public:
 #endif
   void verify();
 };
-
-
 #endif // SHARE_VM_CLASSFILE_DICTIONARY_HPP

src/share/vm/classfile/javaAssertions.cpp

@@ -93,7 +93,7 @@ void JavaAssertions::addOption(const char* name, bool enable) {
 }
 
 oop JavaAssertions::createAssertionStatusDirectives(TRAPS) {
-  symbolHandle asd_sym = vmSymbolHandles::java_lang_AssertionStatusDirectives();
+  Symbol* asd_sym = vmSymbols::java_lang_AssertionStatusDirectives();
   klassOop k = SystemDictionary::resolve_or_fail(asd_sym, true, CHECK_NULL);
   instanceKlassHandle asd_klass (THREAD, k);
   asd_klass->initialize(CHECK_NULL);

src/share/vm/classfile/javaClasses.cpp

@@ -36,7 +36,7 @@
 #include "oops/klass.hpp"
 #include "oops/klassOop.hpp"
 #include "oops/methodOop.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "oops/typeArrayOop.hpp"
 #include "runtime/fieldDescriptor.hpp"
 #include "runtime/handles.inline.hpp"
@@ -57,7 +57,7 @@
 #endif
 
 static bool find_field(instanceKlass* ik,
-                       symbolOop name_symbol, symbolOop signature_symbol,
+                       Symbol* name_symbol, Symbol* signature_symbol,
                        fieldDescriptor* fd,
                        bool allow_super = false) {
   if (allow_super)
@@ -69,7 +69,7 @@ static bool find_field(instanceKlass* ik,
 // Helpful routine for computing field offsets at run time rather than hardcoding them
 static void
 compute_offset(int &dest_offset,
-               klassOop klass_oop, symbolOop name_symbol, symbolOop signature_symbol,
+               klassOop klass_oop, Symbol* name_symbol, Symbol* signature_symbol,
                bool allow_super = false) {
   fieldDescriptor fd;
   instanceKlass* ik = instanceKlass::cast(klass_oop);
@@ -84,7 +84,7 @@ compute_offset(int &dest_offset,
 // Same as above but for "optional" offsets that might not be present in certain JDK versions
 static void
 compute_optional_offset(int& dest_offset,
-                        klassOop klass_oop, symbolOop name_symbol, symbolOop signature_symbol,
+                        klassOop klass_oop, Symbol* name_symbol, Symbol* signature_symbol,
                         bool allow_super = false) {
   fieldDescriptor fd;
   instanceKlass* ik = instanceKlass::cast(klass_oop);
@@ -164,7 +164,7 @@ oop java_lang_String::create_oop_from_str(const char* utf8_str, TRAPS) {
   return h_obj();
 }
 
-Handle java_lang_String::create_from_symbol(symbolHandle symbol, TRAPS) {
+Handle java_lang_String::create_from_symbol(Symbol* symbol, TRAPS) {
   int length = UTF8::unicode_length((char*)symbol->bytes(), symbol->utf8_length());
   Handle h_obj = basic_create(length, false, CHECK_NH);
   if (length > 0) {
@@ -278,17 +278,17 @@ jchar* java_lang_String::as_unicode_string(oop java_string, int& length) {
   return result;
 }
 
-symbolHandle java_lang_String::as_symbol(Handle java_string, TRAPS) {
+Symbol* java_lang_String::as_symbol(Handle java_string, TRAPS) {
   oop          obj    = java_string();
   typeArrayOop value  = java_lang_String::value(obj);
   int          offset = java_lang_String::offset(obj);
   int          length = java_lang_String::length(obj);
   jchar* base = (length == 0) ? NULL : value->char_at_addr(offset);
-  symbolOop sym = SymbolTable::lookup_unicode(base, length, THREAD);
-  return symbolHandle(THREAD, sym);
+  Symbol* sym = SymbolTable::lookup_unicode(base, length, THREAD);
+  return sym;
 }
 
-symbolOop java_lang_String::as_symbol_or_null(oop java_string) {
+Symbol* java_lang_String::as_symbol_or_null(oop java_string) {
   typeArrayOop value  = java_lang_String::value(java_string);
   int          offset = java_lang_String::offset(java_string);
   int          length = java_lang_String::length(java_string);
@@ -437,7 +437,7 @@ klassOop java_lang_Class::as_klassOop(oop java_class) {
 
 void java_lang_Class::print_signature(oop java_class, outputStream* st) {
   assert(java_lang_Class::is_instance(java_class), "must be a Class object");
-  symbolOop name = NULL;
+  Symbol* name = NULL;
   bool is_instance = false;
   if (is_primitive(java_class)) {
     name = vmSymbols::type_signature(primitive_type(java_class));
@@ -455,25 +455,32 @@ void java_lang_Class::print_signature(oop java_class, outputStream* st) {
   if (is_instance)  st->print(";");
 }
 
-symbolOop java_lang_Class::as_signature(oop java_class, bool intern_if_not_found, TRAPS) {
+Symbol* java_lang_Class::as_signature(oop java_class, bool intern_if_not_found, TRAPS) {
   assert(java_lang_Class::is_instance(java_class), "must be a Class object");
-  symbolOop name = NULL;
+  Symbol* name;
   if (is_primitive(java_class)) {
-    return vmSymbols::type_signature(primitive_type(java_class));
+    name = vmSymbols::type_signature(primitive_type(java_class));
+    // Because this can create a new symbol, the caller has to decrement
+    // the refcount, so make adjustment here and below for symbols returned
+    // that are not created or incremented due to a successful lookup.
+    name->increment_refcount();
   } else {
     klassOop k = as_klassOop(java_class);
     if (!Klass::cast(k)->oop_is_instance()) {
-      return Klass::cast(k)->name();
+      name = Klass::cast(k)->name();
+      name->increment_refcount();
     } else {
       ResourceMark rm;
       const char* sigstr = Klass::cast(k)->signature_name();
       int         siglen = (int) strlen(sigstr);
-      if (!intern_if_not_found)
-        return SymbolTable::probe(sigstr, siglen);
-      else
-        return oopFactory::new_symbol(sigstr, siglen, THREAD);
+      if (!intern_if_not_found) {
+        name = SymbolTable::probe(sigstr, siglen);
+      } else {
+        name = SymbolTable::new_symbol(sigstr, siglen, THREAD);
       }
     }
+  }
+  return name;
 }
 
 
@@ -1022,8 +1029,8 @@ void java_lang_Throwable::print_to_stream(Handle stream, const char* str) {
       JavaCalls::call_virtual(&result,
                               stream,
                               KlassHandle(THREAD, stream->klass()),
-                              vmSymbolHandles::println_name(),
-                              vmSymbolHandles::char_array_void_signature(),
+                              vmSymbols::println_name(),
+                              vmSymbols::char_array_void_signature(),
                               arg,
                               THREAD);
     }
@@ -1077,8 +1084,8 @@ void java_lang_Throwable::print_stack_trace(oop throwable, outputStream* st) {
       JavaCalls::call_virtual(&result,
                               h_throwable,
                               KlassHandle(THREAD, h_throwable->klass()),
-                              vmSymbolHandles::getCause_name(),
-                              vmSymbolHandles::void_throwable_signature(),
+                              vmSymbols::getCause_name(),
+                              vmSymbols::void_throwable_signature(),
                               THREAD);
       // Ignore any exceptions. we are in the middle of exception handling. Same as classic VM.
       if (HAS_PENDING_EXCEPTION) {
@@ -1516,7 +1523,7 @@ oop java_lang_StackTraceElement::create(methodHandle method, int bci, TRAPS) {
   oop methodname = StringTable::intern(method->name(), CHECK_0);
   java_lang_StackTraceElement::set_methodName(element(), methodname);
   // Fill in source file name
-  symbolOop source = instanceKlass::cast(method->method_holder())->source_file_name();
+  Symbol* source = instanceKlass::cast(method->method_holder())->source_file_name();
   oop filename = StringTable::intern(source, CHECK_0);
   java_lang_StackTraceElement::set_fileName(element(), filename);
   // File in source line number
@@ -1732,7 +1739,7 @@ void java_lang_reflect_Constructor::compute_offsets() {
 
 Handle java_lang_reflect_Constructor::create(TRAPS) {
   assert(Universe::is_fully_initialized(), "Need to find another solution to the reflection problem");
-  symbolHandle name = vmSymbolHandles::java_lang_reflect_Constructor();
+  Symbol* name = vmSymbols::java_lang_reflect_Constructor();
   klassOop k = SystemDictionary::resolve_or_fail(name, true, CHECK_NH);
   instanceKlassHandle klass (THREAD, k);
   // Ensure it is initialized
@@ -1854,7 +1861,7 @@ void java_lang_reflect_Field::compute_offsets() {
 
 Handle java_lang_reflect_Field::create(TRAPS) {
   assert(Universe::is_fully_initialized(), "Need to find another solution to the reflection problem");
-  symbolHandle name = vmSymbolHandles::java_lang_reflect_Field();
+  Symbol* name = vmSymbols::java_lang_reflect_Field();
   klassOop k = SystemDictionary::resolve_or_fail(name, true, CHECK_NH);
   instanceKlassHandle klass (THREAD, k);
   // Ensure it is initialized
@@ -2422,16 +2429,19 @@ void java_dyn_MethodType::print_signature(oop mt, outputStream* st) {
   java_lang_Class::print_signature(rtype(mt), st);
 }
 
-symbolOop java_dyn_MethodType::as_signature(oop mt, bool intern_if_not_found, TRAPS) {
+Symbol* java_dyn_MethodType::as_signature(oop mt, bool intern_if_not_found, TRAPS) {
   ResourceMark rm;
   stringStream buffer(128);
   print_signature(mt, &buffer);
   const char* sigstr =       buffer.base();
   int         siglen = (int) buffer.size();
-  if (!intern_if_not_found)
-    return SymbolTable::probe(sigstr, siglen);
-  else
-    return oopFactory::new_symbol(sigstr, siglen, THREAD);
+  Symbol *name;
+  if (!intern_if_not_found) {
+    name = SymbolTable::probe(sigstr, siglen);
+  } else {
+    name = SymbolTable::new_symbol(sigstr, siglen, THREAD);
+  }
+  return name;
 }
 
 oop java_dyn_MethodType::rtype(oop mt) {
@@ -2908,13 +2918,12 @@ void JavaClasses::compute_offsets() {
 bool JavaClasses::check_offset(const char *klass_name, int hardcoded_offset, const char *field_name, const char* field_sig) {
   EXCEPTION_MARK;
   fieldDescriptor fd;
-  symbolHandle klass_sym = oopFactory::new_symbol_handle(klass_name, CATCH);
+  TempNewSymbol klass_sym = SymbolTable::new_symbol(klass_name, CATCH);
   klassOop k = SystemDictionary::resolve_or_fail(klass_sym, true, CATCH);
   instanceKlassHandle h_klass (THREAD, k);
-  //instanceKlassHandle h_klass(klass);
-  symbolHandle f_name = oopFactory::new_symbol_handle(field_name, CATCH);
-  symbolHandle f_sig  = oopFactory::new_symbol_handle(field_sig, CATCH);
-  if (!h_klass->find_local_field(f_name(), f_sig(), &fd)) {
+  TempNewSymbol f_name = SymbolTable::new_symbol(field_name, CATCH);
+  TempNewSymbol f_sig  = SymbolTable::new_symbol(field_sig, CATCH);
+  if (!h_klass->find_local_field(f_name, f_sig, &fd)) {
     tty->print_cr("Nonstatic field %s.%s not found", klass_name, field_name);
     return false;
   }
@@ -2935,12 +2944,12 @@ bool JavaClasses::check_offset(const char *klass_name, int hardcoded_offset, con
 bool JavaClasses::check_static_offset(const char *klass_name, int hardcoded_offset, const char *field_name, const char* field_sig) {
   EXCEPTION_MARK;
   fieldDescriptor fd;
-  symbolHandle klass_sym = oopFactory::new_symbol_handle(klass_name, CATCH);
+  TempNewSymbol klass_sym = SymbolTable::new_symbol(klass_name, CATCH);
   klassOop k = SystemDictionary::resolve_or_fail(klass_sym, true, CATCH);
   instanceKlassHandle h_klass (THREAD, k);
-  symbolHandle f_name = oopFactory::new_symbol_handle(field_name, CATCH);
-  symbolHandle f_sig  = oopFactory::new_symbol_handle(field_sig, CATCH);
-  if (!h_klass->find_local_field(f_name(), f_sig(), &fd)) {
+  TempNewSymbol f_name = SymbolTable::new_symbol(field_name, CATCH);
+  TempNewSymbol f_sig  = SymbolTable::new_symbol(field_sig, CATCH);
+  if (!h_klass->find_local_field(f_name, f_sig, &fd)) {
     tty->print_cr("Static field %s.%s not found", klass_name, field_name);
     return false;
   }
@@ -2960,12 +2969,12 @@ bool JavaClasses::check_static_offset(const char *klass_name, int hardcoded_offs
 bool JavaClasses::check_constant(const char *klass_name, int hardcoded_constant, const char *field_name, const char* field_sig) {
   EXCEPTION_MARK;
   fieldDescriptor fd;
-  symbolHandle klass_sym = oopFactory::new_symbol_handle(klass_name, CATCH);
+  TempNewSymbol klass_sym = SymbolTable::new_symbol(klass_name, CATCH);
   klassOop k = SystemDictionary::resolve_or_fail(klass_sym, true, CATCH);
   instanceKlassHandle h_klass (THREAD, k);
-  symbolHandle f_name = oopFactory::new_symbol_handle(field_name, CATCH);
-  symbolHandle f_sig  = oopFactory::new_symbol_handle(field_sig, CATCH);
-  if (!h_klass->find_local_field(f_name(), f_sig(), &fd)) {
+  TempNewSymbol f_name = SymbolTable::new_symbol(field_name, CATCH);
+  TempNewSymbol f_sig  = SymbolTable::new_symbol(field_sig, CATCH);
+  if (!h_klass->find_local_field(f_name, f_sig, &fd)) {
     tty->print_cr("Static field %s.%s not found", klass_name, field_name);
     return false;
   }

src/share/vm/classfile/javaClasses.hpp

@@ -78,7 +78,7 @@ class java_lang_String : AllStatic {
   static oop    create_oop_from_unicode(jchar* unicode, int len, TRAPS);
   static Handle create_from_str(const char* utf8_str, TRAPS);
   static oop    create_oop_from_str(const char* utf8_str, TRAPS);
-  static Handle create_from_symbol(symbolHandle symbol, TRAPS);
+  static Handle create_from_symbol(Symbol* symbol, TRAPS);
   static Handle create_from_platform_dependent_str(const char* str, TRAPS);
   static Handle char_converter(Handle java_string, jchar from_char, jchar to_char, TRAPS);
 
@@ -116,8 +116,8 @@ class java_lang_String : AllStatic {
   static Handle internalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '.', '/', THREAD); }
 
   // Conversion
-  static symbolHandle as_symbol(Handle java_string, TRAPS);
-  static symbolOop as_symbol_or_null(oop java_string);
+  static Symbol* as_symbol(Handle java_string, TRAPS);
+  static Symbol* as_symbol_or_null(oop java_string);
 
   // Testers
   static bool is_instance(oop obj) {
@@ -167,7 +167,7 @@ class java_lang_Class : AllStatic {
     (*reference_klass) = KlassHandle(refk_oop);
     return result;
   }
-  static symbolOop as_signature(oop java_class, bool intern_if_not_found, TRAPS);
+  static Symbol* as_signature(oop java_class, bool intern_if_not_found, TRAPS);
   static void print_signature(oop java_class, outputStream *st);
   // Testing
   static bool is_instance(oop obj) {
@@ -1039,7 +1039,7 @@ class java_dyn_MethodType: AllStatic {
   static oop            ptype(oop mt, int index);
   static int            ptype_count(oop mt);
 
-  static symbolOop      as_signature(oop mt, bool intern_if_not_found, TRAPS);
+  static Symbol*        as_signature(oop mt, bool intern_if_not_found, TRAPS);
   static void           print_signature(oop mt, outputStream* st);
 
   static bool is_instance(oop obj) {

src/share/vm/classfile/loaderConstraints.cpp

@@ -31,28 +31,33 @@
 #include "utilities/hashtable.inline.hpp"
 
 LoaderConstraintTable::LoaderConstraintTable(int nof_buckets)
-  : Hashtable(nof_buckets, sizeof(LoaderConstraintEntry)) {};
+  : Hashtable<klassOop>(nof_buckets, sizeof(LoaderConstraintEntry)) {};
 
 
 LoaderConstraintEntry* LoaderConstraintTable::new_entry(
-                                 unsigned int hash, symbolOop name,
+                                 unsigned int hash, Symbol* name,
                                  klassOop klass, int num_loaders,
                                  int max_loaders) {
   LoaderConstraintEntry* entry;
-  entry = (LoaderConstraintEntry*)Hashtable::new_entry(hash, klass);
+  entry = (LoaderConstraintEntry*)Hashtable<klassOop>::new_entry(hash, klass);
   entry->set_name(name);
   entry->set_num_loaders(num_loaders);
   entry->set_max_loaders(max_loaders);
   return entry;
 }
 
+void LoaderConstraintTable::free_entry(LoaderConstraintEntry *entry) {
+  // decrement name refcount before freeing
+  entry->name()->decrement_refcount();
+  Hashtable<klassOop>::free_entry(entry);
+}
+
 
 void LoaderConstraintTable::oops_do(OopClosure* f) {
   for (int index = 0; index < table_size(); index++) {
     for (LoaderConstraintEntry* probe = bucket(index);
                                 probe != NULL;
                                 probe = probe->next()) {
-      f->do_oop((oop*)(probe->name_addr()));
       if (probe->klass() != NULL) {
         f->do_oop((oop*)probe->klass_addr());
       }
@@ -65,27 +70,13 @@ void LoaderConstraintTable::oops_do(OopClosure* f) {
   }
 }
 
-// We must keep the symbolOop used in the name alive.  We'll use the
-// loaders to decide if a particular entry can be purged.
-void LoaderConstraintTable::always_strong_classes_do(OopClosure* blk) {
-  // We must keep the symbolOop used in the name alive.
-  for (int cindex = 0; cindex < table_size(); cindex++) {
-    for (LoaderConstraintEntry* lc_probe = bucket(cindex);
-                                lc_probe != NULL;
-                                lc_probe = lc_probe->next()) {
-      assert (lc_probe->name() != NULL,  "corrupted loader constraint table");
-      blk->do_oop((oop*)lc_probe->name_addr());
-    }
-  }
-}
-
 
 // The loaderConstraintTable must always be accessed with the
 // SystemDictionary lock held. This is true even for readers as
 // entries in the table could be being dynamically resized.
 
 LoaderConstraintEntry** LoaderConstraintTable::find_loader_constraint(
-                                    symbolHandle name, Handle loader) {
+                                    Symbol* name, Handle loader) {
 
   unsigned int hash = compute_hash(name);
   int index = hash_to_index(hash);
@@ -93,7 +84,7 @@ LoaderConstraintEntry** LoaderConstraintTable::find_loader_constraint(
   while (*pp) {
     LoaderConstraintEntry* p = *pp;
     if (p->hash() == hash) {
-      if (p->name() == name()) {
+      if (p->name() == name) {
         for (int i = p->num_loaders() - 1; i >= 0; i--) {
           if (p->loader(i) == loader()) {
             return pp;
@@ -177,7 +168,6 @@ void LoaderConstraintTable::purge_loader_constraints(BoolObjectClosure* is_alive
         free_entry(probe);
       } else {
 #ifdef ASSERT
-        assert(is_alive->do_object_b(probe->name()), "name should be live");
         if (probe->klass() != NULL) {
           assert(is_alive->do_object_b(probe->klass()), "klass should be live");
         }
@@ -194,7 +184,7 @@ void LoaderConstraintTable::purge_loader_constraints(BoolObjectClosure* is_alive
   }
 }
 
-bool LoaderConstraintTable::add_entry(symbolHandle class_name,
+bool LoaderConstraintTable::add_entry(Symbol* class_name,
                                       klassOop klass1, Handle class_loader1,
                                       klassOop klass2, Handle class_loader2) {
   int failure_code = 0; // encode different reasons for failing
@@ -233,7 +223,7 @@ bool LoaderConstraintTable::add_entry(symbolHandle class_name,
         unsigned int hash = compute_hash(class_name);
         int index = hash_to_index(hash);
         LoaderConstraintEntry* p;
-        p = new_entry(hash, class_name(), klass, 2, 2);
+        p = new_entry(hash, class_name, klass, 2, 2);
         p->set_loaders(NEW_C_HEAP_ARRAY(oop, 2));
         p->set_loader(0, class_loader1());
         p->set_loader(1, class_loader2());
@@ -244,7 +234,7 @@ bool LoaderConstraintTable::add_entry(symbolHandle class_name,
           ResourceMark rm;
           tty->print("[Adding new constraint for name: %s, loader[0]: %s,"
                      " loader[1]: %s ]\n",
-                     class_name()->as_C_string(),
+                     class_name->as_C_string(),
                      SystemDictionary::loader_name(class_loader1()),
                      SystemDictionary::loader_name(class_loader2())
                      );
@@ -257,7 +247,7 @@ bool LoaderConstraintTable::add_entry(symbolHandle class_name,
             ResourceMark rm;
             tty->print("[Setting class object in existing constraint for"
                        " name: %s and loader %s ]\n",
-                       class_name()->as_C_string(),
+                       class_name->as_C_string(),
                        SystemDictionary::loader_name(class_loader1())
                        );
           }
@@ -288,7 +278,7 @@ bool LoaderConstraintTable::add_entry(symbolHandle class_name,
     }
     tty->print("[Failed to add constraint for name: %s, loader[0]: %s,"
                " loader[1]: %s, Reason: %s ]\n",
-               class_name()->as_C_string(),
+               class_name->as_C_string(),
                SystemDictionary::loader_name(class_loader1()),
                SystemDictionary::loader_name(class_loader2()),
                reason
@@ -303,14 +293,14 @@ bool LoaderConstraintTable::add_entry(symbolHandle class_name,
 // violated
 bool LoaderConstraintTable::check_or_update(instanceKlassHandle k,
                                                    Handle loader,
-                                                   symbolHandle name) {
+                                                   Symbol* name) {
   LoaderConstraintEntry* p = *(find_loader_constraint(name, loader));
   if (p && p->klass() != NULL && p->klass() != k()) {
     if (TraceLoaderConstraints) {
       ResourceMark rm;
       tty->print("[Constraint check failed for name %s, loader %s: "
                  "the presented class object differs from that stored ]\n",
-                 name()->as_C_string(),
+                 name->as_C_string(),
                  SystemDictionary::loader_name(loader()));
     }
     return false;
@@ -321,7 +311,7 @@ bool LoaderConstraintTable::check_or_update(instanceKlassHandle k,
         ResourceMark rm;
         tty->print("[Updating constraint for name %s, loader %s, "
                    "by setting class object ]\n",
-                   name()->as_C_string(),
+                   name->as_C_string(),
                    SystemDictionary::loader_name(loader()));
       }
     }
@@ -329,7 +319,7 @@ bool LoaderConstraintTable::check_or_update(instanceKlassHandle k,
   }
 }
 
-klassOop LoaderConstraintTable::find_constrained_klass(symbolHandle name,
+klassOop LoaderConstraintTable::find_constrained_klass(Symbol* name,
                                                        Handle loader) {
   LoaderConstraintEntry *p = *(find_loader_constraint(name, loader));
   if (p != NULL && p->klass() != NULL)
@@ -442,11 +432,10 @@ void LoaderConstraintTable::verify(Dictionary* dictionary,
     for (LoaderConstraintEntry* probe = bucket(cindex);
                                 probe != NULL;
                                 probe = probe->next()) {
-      guarantee(probe->name()->is_symbol(), "should be symbol");
       if (probe->klass() != NULL) {
         instanceKlass* ik = instanceKlass::cast(probe->klass());
         guarantee(ik->name() == probe->name(), "name should match");
-        symbolHandle name (thread, ik->name());
+        Symbol* name = ik->name();
         Handle loader(thread, ik->class_loader());
         unsigned int d_hash = dictionary->compute_hash(name, loader);
         int d_index = dictionary->hash_to_index(d_hash);

src/share/vm/classfile/loaderConstraints.hpp

@@ -31,7 +31,7 @@
 
 class LoaderConstraintEntry;
 
-class LoaderConstraintTable : public Hashtable {
+class LoaderConstraintTable : public Hashtable<klassOop> {
   friend class VMStructs;
 private:
 
@@ -40,39 +40,39 @@ private:
     _nof_buckets            = 1009                     // number of buckets in hash table
   };
 
-  LoaderConstraintEntry** find_loader_constraint(symbolHandle name,
+  LoaderConstraintEntry** find_loader_constraint(Symbol* name,
                                                  Handle loader);
 
 public:
 
   LoaderConstraintTable(int nof_buckets);
 
-  LoaderConstraintEntry* new_entry(unsigned int hash, symbolOop name,
+  LoaderConstraintEntry* new_entry(unsigned int hash, Symbol* name,
                                    klassOop klass, int num_loaders,
                                    int max_loaders);
+  void free_entry(LoaderConstraintEntry *entry);
 
   LoaderConstraintEntry* bucket(int i) {
-    return (LoaderConstraintEntry*)Hashtable::bucket(i);
+    return (LoaderConstraintEntry*)Hashtable<klassOop>::bucket(i);
   }
 
   LoaderConstraintEntry** bucket_addr(int i) {
-    return (LoaderConstraintEntry**)Hashtable::bucket_addr(i);
+    return (LoaderConstraintEntry**)Hashtable<klassOop>::bucket_addr(i);
   }
 
   // GC support
   void oops_do(OopClosure* f);
-  void always_strong_classes_do(OopClosure* blk);
 
   // Check class loader constraints
-  bool add_entry(symbolHandle name, klassOop klass1, Handle loader1,
+  bool add_entry(Symbol* name, klassOop klass1, Handle loader1,
                                     klassOop klass2, Handle loader2);
 
   // Note:  The main entry point for this module is via SystemDictionary.
-  // SystemDictionary::check_signature_loaders(symbolHandle signature,
+  // SystemDictionary::check_signature_loaders(Symbol* signature,
   //                                           Handle loader1, Handle loader2,
   //                                           bool is_method, TRAPS)
 
-  klassOop find_constrained_klass(symbolHandle name, Handle loader);
+  klassOop find_constrained_klass(Symbol* name, Handle loader);
 
   // Class loader constraints
 
@@ -83,7 +83,7 @@ public:
                                 LoaderConstraintEntry** pp2, klassOop klass);
 
   bool check_or_update(instanceKlassHandle k, Handle loader,
-                              symbolHandle name);
+                              Symbol* name);
 
 
   void purge_loader_constraints(BoolObjectClosure* is_alive);
@@ -94,34 +94,36 @@ public:
 #endif
 };
 
-class LoaderConstraintEntry : public HashtableEntry {
+class LoaderConstraintEntry : public HashtableEntry<klassOop> {
   friend class VMStructs;
 private:
-  symbolOop              _name;                   // class name
+  Symbol*                _name;                   // class name
   int                    _num_loaders;
   int                    _max_loaders;
   oop*                   _loaders;                // initiating loaders
 
 public:
 
-  klassOop klass() { return (klassOop)literal(); }
-  klassOop* klass_addr() { return (klassOop*)literal_addr(); }
+  klassOop klass() { return literal(); }
+  klassOop* klass_addr() { return literal_addr(); }
   void set_klass(klassOop k) { set_literal(k); }
 
   LoaderConstraintEntry* next() {
-    return (LoaderConstraintEntry*)HashtableEntry::next();
+    return (LoaderConstraintEntry*)HashtableEntry<klassOop>::next();
   }
 
   LoaderConstraintEntry** next_addr() {
-    return (LoaderConstraintEntry**)HashtableEntry::next_addr();
+    return (LoaderConstraintEntry**)HashtableEntry<klassOop>::next_addr();
   }
   void set_next(LoaderConstraintEntry* next) {
-    HashtableEntry::set_next(next);
+    HashtableEntry<klassOop>::set_next(next);
   }
 
-  symbolOop name() { return _name; }
-  symbolOop* name_addr() { return &_name; }
-  void set_name(symbolOop name) { _name = name; }
+  Symbol* name() { return _name; }
+  void set_name(Symbol* name) {
+    _name = name;
+    if (name != NULL) name->increment_refcount();
+  }
 
   int num_loaders() { return _num_loaders; }
   void set_num_loaders(int i) { _num_loaders = i; }

src/share/vm/classfile/placeholders.cpp

@@ -31,10 +31,12 @@
 
 // Placeholder methods
 
-PlaceholderEntry* PlaceholderTable::new_entry(int hash, symbolOop name,
+PlaceholderEntry* PlaceholderTable::new_entry(int hash, Symbol* name,
                                               oop loader, bool havesupername,
-                                              symbolOop supername) {
-  PlaceholderEntry* entry = (PlaceholderEntry*)Hashtable::new_entry(hash, name);
+                                              Symbol* supername) {
+  PlaceholderEntry* entry = (PlaceholderEntry*)Hashtable<Symbol*>::new_entry(hash, name);
+  // Hashtable with Symbol* literal must increment and decrement refcount.
+  name->increment_refcount();
   entry->set_loader(loader);
   entry->set_havesupername(havesupername);
   entry->set_supername(supername);
@@ -46,33 +48,40 @@ PlaceholderEntry* PlaceholderTable::new_entry(int hash, symbolOop name,
   return entry;
 }
 
+void PlaceholderTable::free_entry(PlaceholderEntry* entry) {
+  // decrement Symbol refcount here because Hashtable doesn't.
+  entry->literal()->decrement_refcount();
+  if (entry->supername() != NULL) entry->supername()->decrement_refcount();
+  Hashtable<Symbol*>::free_entry(entry);
+}
+
 
 // Placeholder objects represent classes currently being loaded.
 // All threads examining the placeholder table must hold the
 // SystemDictionary_lock, so we don't need special precautions
 // on store ordering here.
 void PlaceholderTable::add_entry(int index, unsigned int hash,
-                                 symbolHandle class_name, Handle class_loader,
-                                 bool havesupername, symbolHandle supername){
+                                 Symbol* class_name, Handle class_loader,
+                                 bool havesupername, Symbol* supername){
   assert_locked_or_safepoint(SystemDictionary_lock);
-  assert(!class_name.is_null(), "adding NULL obj");
+  assert(class_name != NULL, "adding NULL obj");
 
   // Both readers and writers are locked so it's safe to just
   // create the placeholder and insert it in the list without a membar.
-  PlaceholderEntry* entry = new_entry(hash, class_name(), class_loader(), havesupername, supername());
+  PlaceholderEntry* entry = new_entry(hash, class_name, class_loader(), havesupername, supername);
   add_entry(index, entry);
 }
 
 
 // Remove a placeholder object.
 void PlaceholderTable::remove_entry(int index, unsigned int hash,
-                                    symbolHandle class_name,
+                                    Symbol* class_name,
                                     Handle class_loader) {
   assert_locked_or_safepoint(SystemDictionary_lock);
   PlaceholderEntry** p = bucket_addr(index);
   while (*p) {
     PlaceholderEntry *probe = *p;
-    if (probe->hash() == hash && probe->equals(class_name(), class_loader())) {
+    if (probe->hash() == hash && probe->equals(class_name, class_loader())) {
       // Delete entry
       *p = probe->next();
       free_entry(probe);
@@ -83,29 +92,28 @@ void PlaceholderTable::remove_entry(int index, unsigned int hash,
 }
 
 PlaceholderEntry* PlaceholderTable::get_entry(int index, unsigned int hash,
-                                       symbolHandle class_name,
+                                       Symbol* class_name,
                                        Handle class_loader) {
   assert_locked_or_safepoint(SystemDictionary_lock);
 
-  symbolOop class_name_ = class_name();
   oop class_loader_ = class_loader();
 
   for (PlaceholderEntry *place_probe = bucket(index);
                          place_probe != NULL;
                          place_probe = place_probe->next()) {
     if (place_probe->hash() == hash &&
-        place_probe->equals(class_name_, class_loader_)) {
+        place_probe->equals(class_name, class_loader_)) {
       return place_probe;
     }
   }
   return NULL;
 }
 
-symbolOop PlaceholderTable::find_entry(int index, unsigned int hash,
-                                       symbolHandle class_name,
+Symbol* PlaceholderTable::find_entry(int index, unsigned int hash,
+                                       Symbol* class_name,
                                        Handle class_loader) {
   PlaceholderEntry* probe = get_entry(index, hash, class_name, class_loader);
-  return (probe? probe->klass(): symbolOop(NULL));
+  return (probe? probe->klassname(): (Symbol*)NULL);
 }
 
   // find_and_add returns probe pointer - old or new
@@ -113,7 +121,7 @@ symbolOop PlaceholderTable::find_entry(int index, unsigned int hash,
   // If entry exists, reuse entry
   // For both, push SeenThread for classloadAction
   // if havesupername: this is used for circularity for instanceklass loading
-PlaceholderEntry* PlaceholderTable::find_and_add(int index, unsigned int hash, symbolHandle name, Handle loader, classloadAction action, symbolHandle supername, Thread* thread) {
+PlaceholderEntry* PlaceholderTable::find_and_add(int index, unsigned int hash, Symbol* name, Handle loader, classloadAction action, Symbol* supername, Thread* thread) {
   PlaceholderEntry* probe = get_entry(index, hash, name, loader);
   if (probe == NULL) {
     // Nothing found, add place holder
@@ -122,7 +130,7 @@ PlaceholderEntry* PlaceholderTable::find_and_add(int index, unsigned int hash, s
   } else {
     if (action == LOAD_SUPER) {
       probe->set_havesupername(true);
-      probe->set_supername(supername());
+      probe->set_supername(supername);
     }
   }
   if (probe) probe->add_seen_thread(thread, action);
@@ -145,7 +153,7 @@ PlaceholderEntry* PlaceholderTable::find_and_add(int index, unsigned int hash, s
 // Therefore - must always check SD first
 // Ignores the case where entry is not found
 void PlaceholderTable::find_and_remove(int index, unsigned int hash,
-                       symbolHandle name, Handle loader, Thread* thread) {
+                       Symbol* name, Handle loader, Thread* thread) {
     assert_locked_or_safepoint(SystemDictionary_lock);
     PlaceholderEntry *probe = get_entry(index, hash, name, loader);
     if (probe != NULL) {
@@ -158,7 +166,7 @@ void PlaceholderTable::find_and_remove(int index, unsigned int hash,
   }
 
 PlaceholderTable::PlaceholderTable(int table_size)
-    : TwoOopHashtable(table_size, sizeof(PlaceholderEntry)) {
+    : TwoOopHashtable<Symbol*>(table_size, sizeof(PlaceholderEntry)) {
 }
 
 
@@ -174,26 +182,22 @@ void PlaceholderTable::oops_do(OopClosure* f) {
 
 
 void PlaceholderEntry::oops_do(OopClosure* blk) {
-  assert(klass() != NULL, "should have a non-null klass");
-  blk->do_oop((oop*)klass_addr());
+  assert(klassname() != NULL, "should have a non-null klass");
   if (_loader != NULL) {
     blk->do_oop(loader_addr());
   }
-  if (_supername != NULL) {
-    blk->do_oop((oop*)supername_addr());
-  }
   if (_instanceKlass != NULL) {
     blk->do_oop((oop*)instanceKlass_addr());
   }
 }
 
 // do all entries in the placeholder table
-void PlaceholderTable::entries_do(void f(symbolOop, oop)) {
+void PlaceholderTable::entries_do(void f(Symbol*, oop)) {
   for (int index = 0; index < table_size(); index++) {
     for (PlaceholderEntry* probe = bucket(index);
                            probe != NULL;
                            probe = probe->next()) {
-      f(probe->klass(), probe->loader());
+      f(probe->klassname(), probe->loader());
     }
   }
 }
@@ -202,7 +206,7 @@ void PlaceholderTable::entries_do(void f(symbolOop, oop)) {
 #ifndef PRODUCT
 // Note, doesn't append a cr
 void PlaceholderEntry::print() const {
-  klass()->print_value();
+  klassname()->print_value();
   if (loader() != NULL) {
     tty->print(", loader ");
     loader()->print_value();
@@ -238,7 +242,6 @@ void PlaceholderEntry::verify() const {
   guarantee(instanceKlass() == NULL
             || Klass::cast(instanceKlass())->oop_is_instance(),
             "checking type of instanceKlass result");
-  klass()->verify();
 }
 
 void PlaceholderTable::verify() {

src/share/vm/classfile/placeholders.hpp

@@ -34,35 +34,36 @@ class PlaceholderEntry;
 // being loaded, as well as arrays of primitives.
 //
 
-class PlaceholderTable : public TwoOopHashtable {
+class PlaceholderTable : public TwoOopHashtable<Symbol*> {
   friend class VMStructs;
 
 public:
   PlaceholderTable(int table_size);
 
-  PlaceholderEntry* new_entry(int hash, symbolOop name, oop loader, bool havesupername, symbolOop supername);
+  PlaceholderEntry* new_entry(int hash, Symbol* name, oop loader, bool havesupername, Symbol* supername);
+  void free_entry(PlaceholderEntry* entry);
 
   PlaceholderEntry* bucket(int i) {
-    return (PlaceholderEntry*)Hashtable::bucket(i);
+    return (PlaceholderEntry*)Hashtable<Symbol*>::bucket(i);
   }
 
   PlaceholderEntry** bucket_addr(int i) {
-    return (PlaceholderEntry**)Hashtable::bucket_addr(i);
+    return (PlaceholderEntry**)Hashtable<Symbol*>::bucket_addr(i);
   }
 
   void add_entry(int index, PlaceholderEntry* new_entry) {
-    Hashtable::add_entry(index, (HashtableEntry*)new_entry);
+    Hashtable<Symbol*>::add_entry(index, (HashtableEntry<Symbol*>*)new_entry);
   }
 
-  void add_entry(int index, unsigned int hash, symbolHandle name,
-                Handle loader, bool havesupername, symbolHandle supername);
+  void add_entry(int index, unsigned int hash, Symbol* name,
+                Handle loader, bool havesupername, Symbol* supername);
 
-// This returns a symbolOop to match type for SystemDictionary
-  symbolOop find_entry(int index, unsigned int hash,
-                       symbolHandle name, Handle loader);
+  // This returns a Symbol* to match type for SystemDictionary
+  Symbol* find_entry(int index, unsigned int hash,
+                       Symbol* name, Handle loader);
 
   PlaceholderEntry* get_entry(int index, unsigned int hash,
-                       symbolHandle name, Handle loader);
+                       Symbol* name, Handle loader);
 
 // caller to create a placeholder entry must enumerate an action
 // caller claims ownership of that action
@@ -84,22 +85,22 @@ public:
   // If no entry exists, add a placeholder entry and push SeenThread
   // If entry exists, reuse entry and push SeenThread for classloadAction
   PlaceholderEntry* find_and_add(int index, unsigned int hash,
-                                 symbolHandle name, Handle loader,
-                                 classloadAction action, symbolHandle supername,
+                                 Symbol* name, Handle loader,
+                                 classloadAction action, Symbol* supername,
                                  Thread* thread);
 
   void remove_entry(int index, unsigned int hash,
-                    symbolHandle name, Handle loader);
+                    Symbol* name, Handle loader);
 
 // Remove placeholder information
   void find_and_remove(int index, unsigned int hash,
-                       symbolHandle name, Handle loader, Thread* thread);
+                       Symbol* name, Handle loader, Thread* thread);
 
   // GC support.
   void oops_do(OopClosure* f);
 
   // JVMTI support
-  void entries_do(void f(symbolOop, oop));
+  void entries_do(void f(Symbol*, oop));
 
 #ifndef PRODUCT
   void print();
@@ -151,14 +152,14 @@ public:
 // on store ordering here.
 // The system dictionary is the only user of this class.
 
-class PlaceholderEntry : public HashtableEntry {
+class PlaceholderEntry : public HashtableEntry<Symbol*> {
   friend class VMStructs;
 
 
  private:
   oop               _loader;        // initiating loader
   bool              _havesupername; // distinguish between null supername, and unknown
-  symbolOop         _supername;
+  Symbol*           _supername;
   Thread*           _definer;       // owner of define token
   klassOop          _instanceKlass; // instanceKlass from successful define
   SeenThread*       _superThreadQ;  // doubly-linked queue of Threads loading a superclass for this class
@@ -173,8 +174,7 @@ class PlaceholderEntry : public HashtableEntry {
 
  public:
   // Simple accessors, used only by SystemDictionary
-  symbolOop          klass()               const { return (symbolOop)literal(); }
-  symbolOop*         klass_addr()          { return (symbolOop*)literal_addr(); }
+  Symbol*            klassname()           const { return literal(); }
 
   oop                loader()              const { return _loader; }
   void               set_loader(oop loader) { _loader = loader; }
@@ -183,9 +183,11 @@ class PlaceholderEntry : public HashtableEntry {
   bool               havesupername()       const { return _havesupername; }
   void               set_havesupername(bool havesupername) { _havesupername = havesupername; }
 
-  symbolOop          supername()           const { return _supername; }
-  void               set_supername(symbolOop supername) { _supername = supername; }
-  symbolOop*         supername_addr()      { return &_supername; }
+  Symbol*            supername()           const { return _supername; }
+  void               set_supername(Symbol* supername) {
+    _supername = supername;
+    if (_supername != NULL) _supername->increment_refcount();
+  }
 
   Thread*            definer()             const {return _definer; }
   void               set_definer(Thread* definer) { _definer = definer; }
@@ -204,17 +206,17 @@ class PlaceholderEntry : public HashtableEntry {
   void               set_defineThreadQ(SeenThread* SeenThread) { _defineThreadQ = SeenThread; }
 
   PlaceholderEntry* next() const {
-    return (PlaceholderEntry*)HashtableEntry::next();
+    return (PlaceholderEntry*)HashtableEntry<Symbol*>::next();
   }
 
   PlaceholderEntry** next_addr() {
-    return (PlaceholderEntry**)HashtableEntry::next_addr();
+    return (PlaceholderEntry**)HashtableEntry<Symbol*>::next_addr();
   }
 
   // Test for equality
   // Entries are unique for class/classloader name pair
-  bool equals(symbolOop class_name, oop class_loader) const {
-    return (klass() == class_name && loader() == class_loader);
+  bool equals(Symbol* class_name, oop class_loader) const {
+    return (klassname() == class_name && loader() == class_loader);
   }
 
   SeenThread* actionToQueue(PlaceholderTable::classloadAction action) {

src/share/vm/classfile/resolutionErrors.cpp

@@ -32,12 +32,12 @@
 
 // add new entry to the table
 void ResolutionErrorTable::add_entry(int index, unsigned int hash,
-                                     constantPoolHandle pool, int cp_index, symbolHandle error)
+                                     constantPoolHandle pool, int cp_index, Symbol* error)
 {
   assert_locked_or_safepoint(SystemDictionary_lock);
-  assert(!pool.is_null() && !error.is_null(), "adding NULL obj");
+  assert(!pool.is_null() && error != NULL, "adding NULL obj");
 
-  ResolutionErrorEntry* entry = new_entry(hash, pool(), cp_index, error());
+  ResolutionErrorEntry* entry = new_entry(hash, pool(), cp_index, error);
   add_entry(index, entry);
 }
 
@@ -57,20 +57,35 @@ ResolutionErrorEntry* ResolutionErrorTable::find_entry(int index, unsigned int h
   return NULL;
 }
 
+void ResolutionErrorEntry::set_error(Symbol* e) {
+  assert(e == NULL || _error == NULL, "cannot reset error");
+  _error = e;
+  if (_error != NULL) _error->increment_refcount();
+}
+
 // create new error entry
 ResolutionErrorEntry* ResolutionErrorTable::new_entry(int hash, constantPoolOop pool,
-                                                      int cp_index, symbolOop error)
+                                                      int cp_index, Symbol* error)
 {
-  ResolutionErrorEntry* entry = (ResolutionErrorEntry*)Hashtable::new_entry(hash, pool);
+  ResolutionErrorEntry* entry = (ResolutionErrorEntry*)Hashtable<constantPoolOop>::new_entry(hash, pool);
   entry->set_cp_index(cp_index);
+  NOT_PRODUCT(entry->set_error(NULL);)
   entry->set_error(error);
 
   return entry;
 }
 
+void ResolutionErrorTable::free_entry(ResolutionErrorEntry *entry) {
+  // decrement error refcount
+  assert(entry->error() != NULL, "error should be set");
+  entry->error()->decrement_refcount();
+  Hashtable<constantPoolOop>::free_entry(entry);
+}
+
+
 // create resolution error table
 ResolutionErrorTable::ResolutionErrorTable(int table_size)
-    : Hashtable(table_size, sizeof(ResolutionErrorEntry)) {
+    : Hashtable<constantPoolOop>(table_size, sizeof(ResolutionErrorEntry)) {
 }
 
 // GC support
@@ -80,7 +95,7 @@ void ResolutionErrorTable::oops_do(OopClosure* f) {
                            probe != NULL;
                            probe = probe->next()) {
       assert(probe->pool() != (constantPoolOop)NULL, "resolution error table is corrupt");
-      assert(probe->error() != (symbolOop)NULL, "resolution error table is corrupt");
+      assert(probe->error() != (Symbol*)NULL, "resolution error table is corrupt");
       probe->oops_do(f);
     }
   }
@@ -89,20 +104,6 @@ void ResolutionErrorTable::oops_do(OopClosure* f) {
 // GC support
 void ResolutionErrorEntry::oops_do(OopClosure* blk) {
   blk->do_oop((oop*)pool_addr());
-  blk->do_oop((oop*)error_addr());
-}
-
-// We must keep the symbolOop used in the error alive. The constantPoolOop will
-// decide when the entry can be purged.
-void ResolutionErrorTable::always_strong_classes_do(OopClosure* blk) {
-  for (int i = 0; i < table_size(); i++) {
-    for (ResolutionErrorEntry* probe = bucket(i);
-                           probe != NULL;
-                           probe = probe->next()) {
-      assert(probe->error() != (symbolOop)NULL, "resolution error table is corrupt");
-      blk->do_oop((oop*)probe->error_addr());
-    }
-  }
 }
 
 // Remove unloaded entries from the table

src/share/vm/classfile/resolutionErrors.hpp

@@ -33,27 +33,28 @@ class ResolutionErrorEntry;
 // ResolutionError objects are used to record errors encountered during
 // constant pool resolution (JVMS 5.4.3).
 
-class ResolutionErrorTable : public Hashtable {
+class ResolutionErrorTable : public Hashtable<constantPoolOop> {
 
 public:
   ResolutionErrorTable(int table_size);
 
-  ResolutionErrorEntry* new_entry(int hash, constantPoolOop pool, int cp_index, symbolOop error);
+  ResolutionErrorEntry* new_entry(int hash, constantPoolOop pool, int cp_index, Symbol* error);
+  void free_entry(ResolutionErrorEntry *entry);
 
   ResolutionErrorEntry* bucket(int i) {
-    return (ResolutionErrorEntry*)Hashtable::bucket(i);
+    return (ResolutionErrorEntry*)Hashtable<constantPoolOop>::bucket(i);
   }
 
   ResolutionErrorEntry** bucket_addr(int i) {
-    return (ResolutionErrorEntry**)Hashtable::bucket_addr(i);
+    return (ResolutionErrorEntry**)Hashtable<constantPoolOop>::bucket_addr(i);
   }
 
   void add_entry(int index, ResolutionErrorEntry* new_entry) {
-    Hashtable::add_entry(index, (HashtableEntry*)new_entry);
+    Hashtable<constantPoolOop>::add_entry(index, (HashtableEntry<constantPoolOop>*)new_entry);
   }
 
   void add_entry(int index, unsigned int hash,
-                 constantPoolHandle pool, int which, symbolHandle error);
+                 constantPoolHandle pool, int which, Symbol* error);
 
 
   // find error given the constant pool and constant pool index
@@ -68,18 +69,15 @@ public:
   // purges unloaded entries from the table
   void purge_resolution_errors(BoolObjectClosure* is_alive);
 
-  // this table keeps symbolOops alive
-  void always_strong_classes_do(OopClosure* blk);
-
   // GC support.
   void oops_do(OopClosure* f);
 };
 
 
-class ResolutionErrorEntry : public HashtableEntry {
+class ResolutionErrorEntry : public HashtableEntry<constantPoolOop> {
  private:
   int               _cp_index;
-  symbolOop         _error;
+  Symbol*           _error;
 
  public:
   constantPoolOop    pool() const               { return (constantPoolOop)literal(); }
@@ -88,16 +86,15 @@ class ResolutionErrorEntry : public HashtableEntry {
   int                cp_index() const           { return _cp_index; }
   void               set_cp_index(int cp_index) { _cp_index = cp_index; }
 
-  symbolOop          error() const              { return _error; }
-  void               set_error(symbolOop e)     { _error = e; }
-  symbolOop*         error_addr()               { return &_error; }
+  Symbol*            error() const              { return _error; }
+  void               set_error(Symbol* e);
 
   ResolutionErrorEntry* next() const {
-    return (ResolutionErrorEntry*)HashtableEntry::next();
+    return (ResolutionErrorEntry*)HashtableEntry<constantPoolOop>::next();
   }
 
   ResolutionErrorEntry** next_addr() {
-    return (ResolutionErrorEntry**)HashtableEntry::next_addr();
+    return (ResolutionErrorEntry**)HashtableEntry<constantPoolOop>::next_addr();
   }
 
   // GC support

src/share/vm/classfile/stackMapFrame.cpp

@@ -27,7 +27,7 @@
 #include "classfile/verifier.hpp"
 #include "memory/resourceArea.hpp"
 #include "oops/oop.inline.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "runtime/handles.inline.hpp"
 #include "utilities/globalDefinitions.hpp"
 
@@ -90,8 +90,7 @@ void StackMapFrame::initialize_object(
 
 VerificationType StackMapFrame::set_locals_from_arg(
     const methodHandle m, VerificationType thisKlass, TRAPS) {
-  symbolHandle signature(THREAD, m->signature());
-  SignatureStream ss(signature);
+  SignatureStream ss(m->signature());
   int init_local_num = 0;
   if (!m->is_static()) {
     init_local_num++;
@@ -118,8 +117,14 @@ VerificationType StackMapFrame::set_locals_from_arg(
     case T_OBJECT:
     case T_ARRAY:
     {
-      symbolOop sig = ss.as_symbol(CHECK_(VerificationType::bogus_type()));
-      return VerificationType::reference_type(symbolHandle(THREAD, sig));
+      Symbol* sig = ss.as_symbol(CHECK_(VerificationType::bogus_type()));
+      // Create another symbol to save as signature stream unreferences
+      // this symbol.
+      Symbol* sig_copy =
+        verifier()->create_temporary_symbol(sig, 0, sig->utf8_length(),
+                                 CHECK_(VerificationType::bogus_type()));
+      assert(sig_copy == sig, "symbols don't match");
+      return VerificationType::reference_type(sig_copy);
     }
     case T_INT:     return VerificationType::integer_type();
     case T_BYTE:    return VerificationType::byte_type();
@@ -157,7 +162,7 @@ bool StackMapFrame::is_assignable_to(
     VerificationType* from, VerificationType* to, int32_t len, TRAPS) const {
   for (int32_t i = 0; i < len; i++) {
     bool subtype = to[i].is_assignable_from(
-      from[i], verifier()->current_class(), THREAD);
+      from[i], verifier(), THREAD);
     if (!subtype) {
       return false;
     }
@@ -187,7 +192,7 @@ VerificationType StackMapFrame::pop_stack_ex(VerificationType type, TRAPS) {
   }
   VerificationType top = _stack[--_stack_size];
   bool subtype = type.is_assignable_from(
-    top, verifier()->current_class(), CHECK_(VerificationType::bogus_type()));
+    top, verifier(), CHECK_(VerificationType::bogus_type()));
   if (!subtype) {
     verifier()->verify_error(_offset, "Bad type on operand stack");
     return VerificationType::bogus_type();
@@ -203,7 +208,7 @@ VerificationType StackMapFrame::get_local(
     return VerificationType::bogus_type();
   }
   bool subtype = type.is_assignable_from(_locals[index],
-    verifier()->current_class(), CHECK_(VerificationType::bogus_type()));
+    verifier(), CHECK_(VerificationType::bogus_type()));
   if (!subtype) {
     verifier()->verify_error(_offset, "Bad local variable type");
     return VerificationType::bogus_type();
@@ -221,9 +226,9 @@ void StackMapFrame::get_local_2(
     return;
   }
   bool subtype1 = type1.is_assignable_from(
-    _locals[index], verifier()->current_class(), CHECK);
+    _locals[index], verifier(), CHECK);
   bool subtype2 = type2.is_assignable_from(
-    _locals[index+1], verifier()->current_class(), CHECK);
+    _locals[index+1], verifier(), CHECK);
   if (!subtype1 || !subtype2) {
     verifier()->verify_error(_offset, "Bad local variable type");
     return;

src/share/vm/classfile/stackMapFrame.hpp

@@ -177,8 +177,7 @@ class StackMapFrame : public ResourceObj {
     if (_stack_size != 0) {
       VerificationType top = _stack[_stack_size - 1];
       bool subtype = type.is_assignable_from(
-        top, verifier()->current_class(),
-        CHECK_(VerificationType::bogus_type()));
+        top, verifier(), CHECK_(VerificationType::bogus_type()));
       if (subtype) {
         _stack_size --;
         NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); )
@@ -194,11 +193,9 @@ class StackMapFrame : public ResourceObj {
     assert(type2.is_long() || type2.is_double(), "must be long/double_2");
     if (_stack_size >= 2) {
       VerificationType top1 = _stack[_stack_size - 1];
-      bool subtype1 = type1.is_assignable_from(
-        top1, verifier()->current_class(), CHECK);
+      bool subtype1 = type1.is_assignable_from(top1, verifier(), CHECK);
       VerificationType top2 = _stack[_stack_size - 2];
-      bool subtype2 = type2.is_assignable_from(
-        top2, verifier()->current_class(), CHECK);
+      bool subtype2 = type2.is_assignable_from(top2, verifier(), CHECK);
       if (subtype1 && subtype2) {
         _stack_size -= 2;
         NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); )

src/share/vm/classfile/stackMapTable.cpp

@@ -184,8 +184,7 @@ VerificationType StackMapReader::parse_verification_type(u1* flags, TRAPS) {
       _stream->stackmap_format_error("bad class index", THREAD);
       return VerificationType::bogus_type();
     }
-    return VerificationType::reference_type(
-      symbolHandle(THREAD, _cp->klass_name_at(class_index)));
+    return VerificationType::reference_type(_cp->klass_name_at(class_index));
   }
   if (tag == ITEM_UninitializedThis) {
     if (flags != NULL) {

src/share/vm/classfile/symbolTable.cpp

@@ -31,7 +31,6 @@
 #include "memory/gcLocker.inline.hpp"
 #include "oops/oop.inline.hpp"
 #include "oops/oop.inline2.hpp"
-#include "oops/symbolKlass.hpp"
 #include "runtime/mutexLocker.hpp"
 #include "utilities/hashtable.inline.hpp"
 
@@ -39,14 +38,97 @@
 
 SymbolTable* SymbolTable::_the_table = NULL;
 
+Symbol* SymbolTable::allocate_symbol(const u1* name, int len, TRAPS) {
+  // Don't allow symbols to be created which cannot fit in a Symbol*.
+  if (len > Symbol::max_length()) {
+    THROW_MSG_0(vmSymbols::java_lang_InternalError(),
+                "name is too long to represent");
+  }
+  Symbol* sym = new (len) Symbol(name, len);
+  assert(sym != NULL, "new should call vm_exit_out_of_memory if C_HEAP is exhausted");
+  return sym;
+}
+
+bool SymbolTable::allocate_symbols(int names_count, const u1** names,
+                                   int* lengths, Symbol** syms, TRAPS) {
+  for (int i = 0; i< names_count; i++) {
+    if (lengths[i] > Symbol::max_length()) {
+      THROW_MSG_0(vmSymbols::java_lang_InternalError(),
+                  "name is too long to represent");
+    }
+  }
+
+  for (int i = 0; i< names_count; i++) {
+    int len = lengths[i];
+    syms[i] = new (len) Symbol(names[i], len);
+    assert(syms[i] != NULL, "new should call vm_exit_out_of_memory if "
+                            "C_HEAP is exhausted");
+  }
+  return true;
+}
+
+// Call function for all symbols in the symbol table.
+void SymbolTable::symbols_do(SymbolClosure *cl) {
+  const int n = the_table()->table_size();
+  for (int i = 0; i < n; i++) {
+    for (HashtableEntry<Symbol*>* p = the_table()->bucket(i);
+         p != NULL;
+         p = p->next()) {
+      cl->do_symbol(p->literal_addr());
+    }
+  }
+}
+
+int SymbolTable::symbols_removed = 0;
+int SymbolTable::symbols_counted = 0;
+
+// Remove unreferenced symbols from the symbol table
+// This is done late during GC.  This doesn't use the hash table unlink because
+// it assumes that the literals are oops.
+void SymbolTable::unlink() {
+  int removed = 0;
+  int total = 0;
+  int memory_total = 0;
+  for (int i = 0; i < the_table()->table_size(); ++i) {
+    for (HashtableEntry<Symbol*>** p = the_table()->bucket_addr(i); *p != NULL; ) {
+      HashtableEntry<Symbol*>* entry = *p;
+      if (entry->is_shared()) {
+        break;
+      }
+      Symbol* s = entry->literal();
+      memory_total += s->object_size();
+      total++;
+      assert(s != NULL, "just checking");
+      // If reference count is zero, remove.
+      if (s->refcount() == 0) {
+        delete s;
+        removed++;
+        *p = entry->next();
+        the_table()->free_entry(entry);
+      } else {
+        p = entry->next_addr();
+      }
+    }
+  }
+  symbols_removed += removed;
+  symbols_counted += total;
+  if (PrintGCDetails) {
+    gclog_or_tty->print(" [Symbols=%d size=%dK] ", total,
+                        (memory_total*HeapWordSize)/1024);
+  }
+}
+
+
 // Lookup a symbol in a bucket.
 
-symbolOop SymbolTable::lookup(int index, const char* name,
+Symbol* SymbolTable::lookup(int index, const char* name,
                               int len, unsigned int hash) {
-  for (HashtableEntry* e = bucket(index); e != NULL; e = e->next()) {
+  for (HashtableEntry<Symbol*>* e = bucket(index); e != NULL; e = e->next()) {
     if (e->hash() == hash) {
-      symbolOop sym = symbolOop(e->literal());
+      Symbol* sym = e->literal();
       if (sym->equals(name, len)) {
+        // something is referencing this symbol now.
+        sym->increment_refcount();
         return sym;
       }
     }
@@ -62,11 +144,11 @@ symbolOop SymbolTable::lookup(int index, const char* name,
 // entries in the symbol table during normal execution (only during
 // safepoints).
 
-symbolOop SymbolTable::lookup(const char* name, int len, TRAPS) {
+Symbol* SymbolTable::lookup(const char* name, int len, TRAPS) {
   unsigned int hashValue = hash_symbol(name, len);
   int index = the_table()->hash_to_index(hashValue);
 
-  symbolOop s = the_table()->lookup(index, name, len, hashValue);
+  Symbol* s = the_table()->lookup(index, name, len, hashValue);
 
   // Found
   if (s != NULL) return s;
@@ -75,7 +157,7 @@ symbolOop SymbolTable::lookup(const char* name, int len, TRAPS) {
   return the_table()->basic_add(index, (u1*)name, len, hashValue, CHECK_NULL);
 }
 
-symbolOop SymbolTable::lookup(symbolHandle sym, int begin, int end, TRAPS) {
+Symbol* SymbolTable::lookup(const Symbol* sym, int begin, int end, TRAPS) {
   char* buffer;
   int index, len;
   unsigned int hashValue;
@@ -87,7 +169,7 @@ symbolOop SymbolTable::lookup(symbolHandle sym, int begin, int end, TRAPS) {
     len = end - begin;
     hashValue = hash_symbol(name, len);
     index = the_table()->hash_to_index(hashValue);
-    symbolOop s = the_table()->lookup(index, name, len, hashValue);
+    Symbol* s = the_table()->lookup(index, name, len, hashValue);
 
     // Found
     if (s != NULL) return s;
@@ -111,18 +193,19 @@ symbolOop SymbolTable::lookup(symbolHandle sym, int begin, int end, TRAPS) {
   return the_table()->basic_add(index, (u1*)buffer, len, hashValue, CHECK_NULL);
 }
 
-symbolOop SymbolTable::lookup_only(const char* name, int len,
+Symbol* SymbolTable::lookup_only(const char* name, int len,
                                    unsigned int& hash) {
   hash = hash_symbol(name, len);
   int index = the_table()->hash_to_index(hash);
 
-  return the_table()->lookup(index, name, len, hash);
+  Symbol* s = the_table()->lookup(index, name, len, hash);
+  return s;
 }
 
 // Suggestion: Push unicode-based lookup all the way into the hashing
 // and probing logic, so there is no need for convert_to_utf8 until
-// an actual new symbolOop is created.
-symbolOop SymbolTable::lookup_unicode(const jchar* name, int utf16_length, TRAPS) {
+// an actual new Symbol* is created.
+Symbol* SymbolTable::lookup_unicode(const jchar* name, int utf16_length, TRAPS) {
   int utf8_length = UNICODE::utf8_length((jchar*) name, utf16_length);
   char stack_buf[128];
   if (utf8_length < (int) sizeof(stack_buf)) {
@@ -137,7 +220,7 @@ symbolOop SymbolTable::lookup_unicode(const jchar* name, int utf16_length, TRAPS
   }
 }
 
-symbolOop SymbolTable::lookup_only_unicode(const jchar* name, int utf16_length,
+Symbol* SymbolTable::lookup_only_unicode(const jchar* name, int utf16_length,
                                            unsigned int& hash) {
   int utf8_length = UNICODE::utf8_length((jchar*) name, utf16_length);
   char stack_buf[128];
@@ -163,25 +246,23 @@ void SymbolTable::add(constantPoolHandle cp, int names_count,
     // do it the hard way
     for (int i=0; i<names_count; i++) {
       int index = table->hash_to_index(hashValues[i]);
-      symbolOop sym = table->basic_add(index, (u1*)names[i], lengths[i],
+      Symbol* sym = table->basic_add(index, (u1*)names[i], lengths[i],
                                        hashValues[i], CHECK);
       cp->symbol_at_put(cp_indices[i], sym);
     }
   }
 }
 
-symbolOop SymbolTable::basic_add(int index, u1 *name, int len,
+Symbol* SymbolTable::basic_add(int index, u1 *name, int len,
                                  unsigned int hashValue, TRAPS) {
   assert(!Universe::heap()->is_in_reserved(name) || GC_locker::is_active(),
          "proposed name of symbol must be stable");
 
   // We assume that lookup() has been called already, that it failed,
   // and symbol was not found.  We create the symbol here.
-  symbolKlass* sk  = (symbolKlass*) Universe::symbolKlassObj()->klass_part();
-  symbolOop s_oop = sk->allocate_symbol(name, len, CHECK_NULL);
-  symbolHandle sym (THREAD, s_oop);
+  Symbol* sym = allocate_symbol(name, len, CHECK_NULL);
 
-  // Allocation must be done before grapping the SymbolTable_lock lock
+  // Allocation must be done before grabbing the SymbolTable_lock lock
   MutexLocker ml(SymbolTable_lock, THREAD);
 
   assert(sym->equals((char*)name, len), "symbol must be properly initialized");
@@ -189,51 +270,51 @@ symbolOop SymbolTable::basic_add(int index, u1 *name, int len,
   // Since look-up was done lock-free, we need to check if another
   // thread beat us in the race to insert the symbol.
 
-  symbolOop test = lookup(index, (char*)name, len, hashValue);
+  Symbol* test = lookup(index, (char*)name, len, hashValue);
   if (test != NULL) {
     // A race occurred and another thread introduced the symbol, this one
     // will be dropped and collected.
+    delete sym;
+    assert(test->refcount() != 0, "lookup should have incremented the count");
     return test;
   }
 
-  HashtableEntry* entry = new_entry(hashValue, sym());
+  HashtableEntry<Symbol*>* entry = new_entry(hashValue, sym);
+  sym->increment_refcount();
   add_entry(index, entry);
-  return sym();
+  return sym;
 }
 
 bool SymbolTable::basic_add(constantPoolHandle cp, int names_count,
                             const char** names, int* lengths,
                             int* cp_indices, unsigned int* hashValues,
                             TRAPS) {
-  symbolKlass* sk  = (symbolKlass*) Universe::symbolKlassObj()->klass_part();
-  symbolOop sym_oops[symbol_alloc_batch_size];
-  bool allocated = sk->allocate_symbols(names_count, names, lengths,
-                                        sym_oops, CHECK_false);
+  Symbol* syms[symbol_alloc_batch_size];
+  bool allocated = allocate_symbols(names_count, (const u1**)names, lengths,
+                                    syms, CHECK_false);
   if (!allocated) {
     return false;
   }
-  symbolHandle syms[symbol_alloc_batch_size];
-  int i;
-  for (i=0; i<names_count; i++) {
-    syms[i] = symbolHandle(THREAD, sym_oops[i]);
-  }
 
   // Allocation must be done before grabbing the SymbolTable_lock lock
   MutexLocker ml(SymbolTable_lock, THREAD);
 
-  for (i=0; i<names_count; i++) {
+  for (int i=0; i<names_count; i++) {
     assert(syms[i]->equals(names[i], lengths[i]), "symbol must be properly initialized");
     // Since look-up was done lock-free, we need to check if another
     // thread beat us in the race to insert the symbol.
     int index = hash_to_index(hashValues[i]);
-    symbolOop test = lookup(index, names[i], lengths[i], hashValues[i]);
+    Symbol* test = lookup(index, names[i], lengths[i], hashValues[i]);
     if (test != NULL) {
       // A race occurred and another thread introduced the symbol, this one
       // will be dropped and collected. Use test instead.
       cp->symbol_at_put(cp_indices[i], test);
+      assert(test->refcount() != 0, "lookup should have incremented the count");
+      delete syms[i];
     } else {
-      symbolOop sym = syms[i]();
-      HashtableEntry* entry = new_entry(hashValues[i], sym);
+      Symbol* sym = syms[i];
+      HashtableEntry<Symbol*>* entry = new_entry(hashValues[i], sym);
+      sym->increment_refcount();  // increment refcount in external hashtable
       add_entry(index, entry);
       cp->symbol_at_put(cp_indices[i], sym);
     }
@@ -245,12 +326,10 @@ bool SymbolTable::basic_add(constantPoolHandle cp, int names_count,
 
 void SymbolTable::verify() {
   for (int i = 0; i < the_table()->table_size(); ++i) {
-    HashtableEntry* p = the_table()->bucket(i);
+    HashtableEntry<Symbol*>* p = the_table()->bucket(i);
     for ( ; p != NULL; p = p->next()) {
-      symbolOop s = symbolOop(p->literal());
+      Symbol* s = (Symbol*)(p->literal());
       guarantee(s != NULL, "symbol is NULL");
-      s->verify();
-      guarantee(s->is_perm(), "symbol not in permspace");
       unsigned int h = hash_symbol((char*)s->bytes(), s->utf8_length());
       guarantee(p->hash() == h, "broken hash in symbol table entry");
       guarantee(the_table()->hash_to_index(h) == i,
@@ -279,10 +358,14 @@ void SymbolTable::print_histogram() {
   int total = 0;
   int max_symbols = 0;
   int out_of_range = 0;
+  int memory_total = 0;
+  int count = 0;
   for (i = 0; i < the_table()->table_size(); i++) {
-    HashtableEntry* p = the_table()->bucket(i);
+    HashtableEntry<Symbol*>* p = the_table()->bucket(i);
     for ( ; p != NULL; p = p->next()) {
-      int counter = symbolOop(p->literal())->utf8_length();
+      memory_total += p->literal()->object_size();
+      count++;
+      int counter = p->literal()->utf8_length();
       total += counter;
       if (counter < results_length) {
         results[counter]++;
@@ -293,6 +376,17 @@ void SymbolTable::print_histogram() {
     }
   }
   tty->print_cr("Symbol Table:");
+  tty->print_cr("Total number of symbols  %5d", count);
+  tty->print_cr("Total size in memory     %5dK",
+          (memory_total*HeapWordSize)/1024);
+  tty->print_cr("Total counted            %5d", symbols_counted);
+  tty->print_cr("Total removed            %5d", symbols_removed);
+  if (symbols_counted > 0) {
+    tty->print_cr("Percent removed          %3.2f",
+          ((float)symbols_removed/(float)symbols_counted)* 100);
+  }
+  tty->print_cr("Reference counts         %5d", Symbol::_total_count);
+  tty->print_cr("Histogram of symbol length:");
   tty->print_cr("%8s %5d", "Total  ", total);
   tty->print_cr("%8s %5d", "Maximum", max_symbols);
   tty->print_cr("%8s %3.2f", "Average",
@@ -304,6 +398,7 @@ void SymbolTable::print_histogram() {
       tty->print_cr("%6d %10d", i, results[i]);
     }
   }
+  if (Verbose) {
     int line_length = 70;
     tty->print_cr("%s %30s", " Length", "Number chains that length");
     for (i = 0; i < results_length; i++) {
@@ -318,10 +413,28 @@ void SymbolTable::print_histogram() {
         tty->cr();
       }
     }
+  }
   tty->print_cr(" %s %d: %d\n", "Number chains longer than",
                     results_length, out_of_range);
 }
 
+void SymbolTable::print() {
+  for (int i = 0; i < the_table()->table_size(); ++i) {
+    HashtableEntry<Symbol*>** p = the_table()->bucket_addr(i);
+    HashtableEntry<Symbol*>* entry = the_table()->bucket(i);
+    if (entry != NULL) {
+      while (entry != NULL) {
+        tty->print(PTR_FORMAT " ", entry->literal());
+        entry->literal()->print();
+        tty->print(" %d", entry->literal()->refcount());
+        p = entry->next_addr();
+        entry = (HashtableEntry<Symbol*>*)HashtableEntry<Symbol*>::make_ptr(*p);
+      }
+      tty->cr();
+    }
+  }
+}
+
 #endif // PRODUCT
 
 // --------------------------------------------------------------------------
@@ -396,7 +509,7 @@ StringTable* StringTable::_the_table = NULL;
 
 oop StringTable::lookup(int index, jchar* name,
                         int len, unsigned int hash) {
-  for (HashtableEntry* l = bucket(index); l != NULL; l = l->next()) {
+  for (HashtableEntry<oop>* l = bucket(index); l != NULL; l = l->next()) {
     if (l->hash() == hash) {
       if (java_lang_String::equals(l->literal(), name, len)) {
         return l->literal();
@@ -436,13 +549,13 @@ oop StringTable::basic_add(int index, Handle string_or_null, jchar* name,
     return test;
   }
 
-  HashtableEntry* entry = new_entry(hashValue, string());
+  HashtableEntry<oop>* entry = new_entry(hashValue, string());
   add_entry(index, entry);
   return string();
 }
 
 
-oop StringTable::lookup(symbolOop symbol) {
+oop StringTable::lookup(Symbol* symbol) {
   ResourceMark rm;
   int length;
   jchar* chars = symbol->as_unicode(length);
@@ -466,7 +579,7 @@ oop StringTable::intern(Handle string_or_null, jchar* name,
                                 hashValue, CHECK_NULL);
 }
 
-oop StringTable::intern(symbolOop symbol, TRAPS) {
+oop StringTable::intern(Symbol* symbol, TRAPS) {
   if (symbol == NULL) return NULL;
   ResourceMark rm(THREAD);
   int length;
@@ -500,9 +613,50 @@ oop StringTable::intern(const char* utf8_string, TRAPS) {
   return result;
 }
 
+void StringTable::unlink(BoolObjectClosure* is_alive) {
+  // Readers of the table are unlocked, so we should only be removing
+  // entries at a safepoint.
+  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
+  for (int i = 0; i < the_table()->table_size(); ++i) {
+    for (HashtableEntry<oop>** p = the_table()->bucket_addr(i); *p != NULL; ) {
+      HashtableEntry<oop>* entry = *p;
+      if (entry->is_shared()) {
+        break;
+      }
+      assert(entry->literal() != NULL, "just checking");
+      if (is_alive->do_object_b(entry->literal())) {
+        p = entry->next_addr();
+      } else {
+        *p = entry->next();
+        the_table()->free_entry(entry);
+      }
+    }
+  }
+}
+
+void StringTable::oops_do(OopClosure* f) {
+  for (int i = 0; i < the_table()->table_size(); ++i) {
+    HashtableEntry<oop>** p = the_table()->bucket_addr(i);
+    HashtableEntry<oop>* entry = the_table()->bucket(i);
+    while (entry != NULL) {
+      f->do_oop((oop*)entry->literal_addr());
+
+      // Did the closure remove the literal from the table?
+      if (entry->literal() == NULL) {
+        assert(!entry->is_shared(), "immutable hashtable entry?");
+        *p = entry->next();
+        the_table()->free_entry(entry);
+      } else {
+        p = entry->next_addr();
+      }
+      entry = (HashtableEntry<oop>*)HashtableEntry<oop>::make_ptr(*p);
+    }
+  }
+}
+
 void StringTable::verify() {
   for (int i = 0; i < the_table()->table_size(); ++i) {
-    HashtableEntry* p = the_table()->bucket(i);
+    HashtableEntry<oop>* p = the_table()->bucket(i);
     for ( ; p != NULL; p = p->next()) {
       oop s = p->literal();
       guarantee(s != NULL, "interned string is NULL");

src/share/vm/classfile/verificationType.cpp

@@ -25,6 +25,7 @@
 #include "precompiled.hpp"
 #include "classfile/symbolTable.hpp"
 #include "classfile/verificationType.hpp"
+#include "classfile/verifier.hpp"
 
 VerificationType VerificationType::from_tag(u1 tag) {
   switch (tag) {
@@ -41,7 +42,8 @@ VerificationType VerificationType::from_tag(u1 tag) {
 }
 
 bool VerificationType::is_reference_assignable_from(
-    const VerificationType& from, instanceKlassHandle context, TRAPS) const {
+    const VerificationType& from, ClassVerifier* context, TRAPS) const {
+  instanceKlassHandle klass = context->current_class();
   if (from.is_null()) {
     // null is assignable to any reference
     return true;
@@ -56,8 +58,8 @@ bool VerificationType::is_reference_assignable_from(
       return true;
     }
     klassOop obj = SystemDictionary::resolve_or_fail(
-        name_handle(), Handle(THREAD, context->class_loader()),
-        Handle(THREAD, context->protection_domain()), true, CHECK_false);
+        name(), Handle(THREAD, klass->class_loader()),
+        Handle(THREAD, klass->protection_domain()), true, CHECK_false);
     KlassHandle this_class(THREAD, obj);
 
     if (this_class->is_interface()) {
@@ -66,13 +68,13 @@ bool VerificationType::is_reference_assignable_from(
       return true;
     } else if (from.is_object()) {
       klassOop from_class = SystemDictionary::resolve_or_fail(
-          from.name_handle(), Handle(THREAD, context->class_loader()),
-          Handle(THREAD, context->protection_domain()), true, CHECK_false);
+          from.name(), Handle(THREAD, klass->class_loader()),
+          Handle(THREAD, klass->protection_domain()), true, CHECK_false);
       return instanceKlass::cast(from_class)->is_subclass_of(this_class());
     }
   } else if (is_array() && from.is_array()) {
-    VerificationType comp_this = get_component(CHECK_false);
-    VerificationType comp_from = from.get_component(CHECK_false);
+    VerificationType comp_this = get_component(context, CHECK_false);
+    VerificationType comp_from = from.get_component(context, CHECK_false);
     if (!comp_this.is_bogus() && !comp_from.is_bogus()) {
       return comp_this.is_assignable_from(comp_from, context, CHECK_false);
     }
@@ -80,9 +82,9 @@ bool VerificationType::is_reference_assignable_from(
   return false;
 }
 
-VerificationType VerificationType::get_component(TRAPS) const {
+VerificationType VerificationType::get_component(ClassVerifier *context, TRAPS) const {
   assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array");
-  symbolOop component;
+  Symbol* component;
   switch (name()->byte_at(1)) {
     case 'Z': return VerificationType(Boolean);
     case 'B': return VerificationType(Byte);
@@ -93,12 +95,12 @@ VerificationType VerificationType::get_component(TRAPS) const {
     case 'F': return VerificationType(Float);
     case 'D': return VerificationType(Double);
     case '[':
-      component = SymbolTable::lookup(
+      component = context->create_temporary_symbol(
         name(), 1, name()->utf8_length(),
         CHECK_(VerificationType::bogus_type()));
       return VerificationType::reference_type(component);
     case 'L':
-      component = SymbolTable::lookup(
+      component = context->create_temporary_symbol(
         name(), 2, name()->utf8_length() - 1,
         CHECK_(VerificationType::bogus_type()));
       return VerificationType::reference_type(component);

src/share/vm/classfile/verificationType.hpp

@@ -29,7 +29,7 @@
 #include "memory/allocation.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/oop.inline.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "runtime/handles.hpp"
 #include "runtime/signature.hpp"
 
@@ -47,6 +47,8 @@ enum {
   ITEM_Bogus = (uint)-1
 };
 
+class ClassVerifier;
+
 class VerificationType VALUE_OBJ_CLASS_SPEC {
   private:
     // Least significant bits of _handle are always 0, so we use these as
@@ -56,7 +58,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
     // will catch this and we'll have to add a descriminator tag to this
     // structure.
     union {
-      symbolOop* _handle;
+      Symbol*   _sym;
       uintptr_t _data;
     } _u;
 
@@ -73,7 +75,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
       TypeMask           = 0x00000003,
 
       // Topmost types encoding
-      Reference          = 0x0,        // _handle contains the name
+      Reference          = 0x0,        // _sym contains the name
       Primitive          = 0x1,        // see below for primitive list
       Uninitialized      = 0x2,        // 0x00ffff00 contains bci
       TypeQuery          = 0x3,        // Meta-types used for category testing
@@ -85,7 +87,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
       Category2_2ndFlag  = 0x04,       // Second word of a two-word value
 
       // special reference values
-      Null               = 0x00000000, // A reference with a 0 handle is null
+      Null               = 0x00000000, // A reference with a 0 sym is null
 
       // Primitives categories (the second byte determines the category)
       Category1          = (Category1Flag     << 1 * BitsPerByte) | Primitive,
@@ -152,17 +154,14 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
   static VerificationType category2_2nd_check()
     { return VerificationType(Category2_2ndQuery); }
 
-  // For reference types, store the actual oop* handle
-  static VerificationType reference_type(symbolHandle sh) {
-      assert(((uintptr_t)sh.raw_value() & 0x3) == 0, "Oops must be aligned");
+  // For reference types, store the actual Symbol
+  static VerificationType reference_type(Symbol* sh) {
+      assert(((uintptr_t)sh & 0x3) == 0, "Oops must be aligned");
       // If the above assert fails in the future because oop* isn't aligned,
       // then this type encoding system will have to change to have a tag value
       // to descriminate between oops and primitives.
-      return VerificationType((uintptr_t)((symbolOop*)sh.raw_value()));
+      return VerificationType((uintptr_t)sh);
   }
-  static VerificationType reference_type(symbolOop s, TRAPS)
-    { return reference_type(symbolHandle(THREAD, s)); }
-
   static VerificationType uninitialized_type(u2 bci)
     { return VerificationType(bci << 1 * BitsPerByte | Uninitialized); }
   static VerificationType uninitialized_this_type()
@@ -242,13 +241,9 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
     return ((_u._data & BciMask) >> 1 * BitsPerByte);
   }
 
-  symbolHandle name_handle() const {
-    assert(is_reference() && !is_null(), "Must be a non-null reference");
-    return symbolHandle(_u._handle, true);
-  }
-  symbolOop name() const {
+  Symbol* name() const {
     assert(is_reference() && !is_null(), "Must be a non-null reference");
-    return *(_u._handle);
+    return _u._sym;
   }
 
   bool equals(const VerificationType& t) const {
@@ -269,7 +264,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
   // is assignable to another.  Returns true if one can assign 'from' to
   // this.
   bool is_assignable_from(
-      const VerificationType& from, instanceKlassHandle context, TRAPS) const {
+      const VerificationType& from, ClassVerifier* context, TRAPS) const {
     if (equals(from) || is_bogus()) {
       return true;
     } else {
@@ -298,7 +293,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
     }
   }
 
-  VerificationType get_component(TRAPS) const;
+  VerificationType get_component(ClassVerifier* context, TRAPS) const;
 
   int dimensions() const {
     assert(is_array(), "Must be an array");
@@ -312,7 +307,7 @@ class VerificationType VALUE_OBJ_CLASS_SPEC {
  private:
 
   bool is_reference_assignable_from(
-    const VerificationType&, instanceKlassHandle, TRAPS) const;
+    const VerificationType&, ClassVerifier*, TRAPS) const;
 };
 
 #endif // SHARE_VM_CLASSFILE_VERIFICATIONTYPE_HPP

src/share/vm/code/compiledIC.cpp

@@ -34,7 +34,7 @@
 #include "memory/oopFactory.hpp"
 #include "oops/methodOop.hpp"
 #include "oops/oop.inline.hpp"
-#include "oops/symbolOop.hpp"
+#include "oops/symbol.hpp"
 #include "runtime/icache.hpp"
 #include "runtime/sharedRuntime.hpp"
 #include "runtime/stubRoutines.hpp"

src/share/vm/code/dependencies.cpp

@@ -628,8 +628,8 @@ class ClassHierarchyWalker {
 
  private:
   // optional method descriptor to check for:
-  symbolOop _name;
-  symbolOop _signature;
+  Symbol* _name;
+  Symbol* _signature;
 
   // special classes which are not allowed to be witnesses:
   klassOop  _participants[PARTICIPANT_LIMIT+1];

src/share/vm/compiler/compileLog.hpp

@@ -63,7 +63,7 @@ class CompileLog : public xmlStream {
   stringStream* context()                        { return &_context; }
 
   void          name(ciSymbol* s);               // name='s'
-  void          name(symbolHandle s)             { xmlStream::name(s); }
+  void          name(Symbol* s)                  { xmlStream::name(s); }
 
   // Output an object description, return obj->ident().
   int           identify(ciObject* obj);

src/share/vm/compiler/compilerOracle.hpp

@@ -31,8 +31,6 @@
 // CompilerOracle is an interface for turning on and off compilation
 // for some methods
 
-class symbolHandle;
-
 class CompilerOracle : AllStatic {
  private:
   static bool _quiet;