--- a/make/BuildNashorn.gmk	Thu Nov 05 08:15:48 2015 -0800
+++ b/make/BuildNashorn.gmk	Thu Nov 05 13:42:32 2015 -0800
@@ -28,6 +28,7 @@
 
 -include $(SPEC)
 include MakeBase.gmk
+include JarArchive.gmk
 include JavaCompilation.gmk
 include SetupJavaCompilers.gmk
 
@@ -108,7 +109,7 @@
 MANIFEST_ATTRIBUTES := Name: jdk/nashorn/\nImplementation-Title: Oracle Nashorn\nImplementation-Version: $(NASHORN_FULL_VERSION)
 
 # Create nashorn.jar from the final classes dir
-$(eval $(call SetupArchive,BUILD_NASHORN_JAR, \
+$(eval $(call SetupJarArchive, BUILD_NASHORN_JAR, \
     DEPENDENCIES := $(NASGEN_RUN_FILE) \
         $(VERSION_FILE), \
     SRCS := $(NASHORN_CLASSES_DIR), \
@@ -116,7 +117,8 @@
     MANIFEST := $(NASHORN_TOPDIR)/src/jdk.scripting.nashorn/share/classes/META-INF/MANIFEST.MF, \
     EXTRA_MANIFEST_ATTR := $(MANIFEST_ATTRIBUTES), \
     SKIP_METAINF := true, \
-    JAR := $(NASHORN_JAR)))
+    JAR := $(NASHORN_JAR), \
+))
 
 compile: $(NASHORN_RUN_FILE) $(VERSION_FILE)
 all: $(NASHORN_JAR)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/samples/find_underscores.js	Thu Nov 05 13:42:32 2015 -0800
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   - Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *   - Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ *   - Neither the name of Oracle nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// Usage: jjs find_underscores.js -- <directory>
+
+if (arguments.length == 0) {
+    print("Usage: jjs find_underscores.js -- <directory>");
+    exit(1);
+}
+
+// Java types used
+var File = Java.type("java.io.File");
+var Files = Java.type("java.nio.file.Files");
+var StringArray = Java.type("java.lang.String[]");
+var ToolProvider = Java.type("javax.tools.ToolProvider");
+var Tree = Java.type("com.sun.source.tree.Tree");
+var Trees = Java.type("com.sun.source.util.Trees");
+var TreeScanner = Java.type("com.sun.source.util.TreeScanner");
+
+function findUnderscores() {
+    // get the system compiler tool
+    var compiler = ToolProvider.systemJavaCompiler;
+    // get standard file manager
+    var fileMgr = compiler.getStandardFileManager(null, null, null);
+    // Using Java.to convert script array (arguments) to a Java String[]
+    var compUnits = fileMgr.getJavaFileObjects(Java.to(arguments, StringArray));
+    // create a new compilation task
+    var task = compiler.getTask(null, fileMgr, null, null, null, compUnits);
+    var sourcePositions = Trees.instance(task).sourcePositions;
+    // subclass SimpleTreeVisitor - to find underscore variable names
+    var UnderscoreFinder = Java.extend(TreeScanner);
+
+    var visitor = new UnderscoreFinder() {
+        // override to capture information on current compilation unit
+        visitCompilationUnit: function(compUnit, p) {
+            this.compUnit = compUnit;
+            this.lineMap = compUnit.lineMap;
+            this.fileName = compUnit.sourceFile.name;
+
+            return Java.super(visitor).visitCompilationUnit(compUnit, p);
+        },
+
+        // override to check variable name
+        visitVariable: function(node, p) {
+            if (node.name.toString() == "_") {
+                var pos = sourcePositions.getStartPosition(this.compUnit, node);
+                var line = this.lineMap.getLineNumber(pos);
+                var col = this.lineMap.getColumnNumber(pos);
+                print(node + " @ " + this.fileName + ":" + line + ":" + col);
+            }
+
+            return Java.super(visitor).visitVariable(node, p);
+        }
+    }
+
+    for each (var cu in task.parse()) {
+        cu.accept(visitor, null);
+    }
+}
+
+// for each ".java" file in directory (recursively).
+function main(dir) {
+    var totalCount = 0;
+    Files.walk(dir.toPath()).
+      forEach(function(p) {
+          var name = p.toFile().absolutePath;
+          if (name.endsWith(".java")) {
+              findUnderscores(p);
+          }
+      });
+}
+
+main(new File(arguments[0]));

--- a/src/jdk.scripting.nashorn/share/classes/jdk/internal/dynalink/support/NameCodec.java	Thu Nov 05 08:15:48 2015 -0800
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,207 +0,0 @@
-/*
- * Copyright (c) 2010, 2013, 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.  Oracle designates this
- * particular file as subject to the "Classpath" exception as provided
- * by Oracle in the LICENSE file that accompanied this code.
- *
- * 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.
- */
-
-/*
- * This file is available under and governed by the GNU General Public
- * License version 2 only, as published by the Free Software Foundation.
- * However, the following notice accompanied the original version of this
- * file, and Oracle licenses the original version of this file under the BSD
- * license:
- */
-/*
-   Copyright 2009-2013 Attila Szegedi
-
-   Licensed under both the Apache License, Version 2.0 (the "Apache License")
-   and the BSD License (the "BSD License"), with licensee being free to
-   choose either of the two at their discretion.
-
-   You may not use this file except in compliance with either the Apache
-   License or the BSD License.
-
-   If you choose to use this file in compliance with the Apache License, the
-   following notice applies to you:
-
-       You may obtain a copy of the Apache License at
-
-           http://www.apache.org/licenses/LICENSE-2.0
-
-       Unless required by applicable law or agreed to in writing, software
-       distributed under the License is distributed on an "AS IS" BASIS,
-       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-       implied. See the License for the specific language governing
-       permissions and limitations under the License.
-
-   If you choose to use this file in compliance with the BSD License, the
-   following notice applies to you:
-
-       Redistribution and use in source and binary forms, with or without
-       modification, are permitted provided that the following conditions are
-       met:
-       * Redistributions of source code must retain the above copyright
-         notice, this list of conditions and the following disclaimer.
-       * Redistributions in binary form must reproduce the above copyright
-         notice, this list of conditions and the following disclaimer in the
-         documentation and/or other materials provided with the distribution.
-       * Neither the name of the copyright holder nor the names of
-         contributors may be used to endorse or promote products derived from
-         this software without specific prior written permission.
-
-       THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
-       IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-       TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
-       PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
-       BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-       CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
-       BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
-       WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
-       OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
-       ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-*/
-
-package jdk.internal.dynalink.support;
-
-
-/**
- * Implements the name mangling and demangling as specified by John Rose's
- * <a href="https://blogs.oracle.com/jrose/entry/symbolic_freedom_in_the_vm"
- * target="_blank">"Symbolic Freedom in the VM"</a> article. Normally, you would
- * mangle the names in the call sites as you're generating bytecode, and then
- * demangle them when you receive them in bootstrap methods.
- */
-public final class NameCodec {
-    private static final char ESCAPE_CHAR = '\\';
-    private static final char EMPTY_ESCAPE = '=';
-    private static final String EMPTY_NAME = new String(new char[] { ESCAPE_CHAR, EMPTY_ESCAPE });
-    private static final char EMPTY_CHAR = 0xFEFF;
-
-    private static final int MIN_ENCODING = '$';
-    private static final int MAX_ENCODING = ']';
-    private static final char[] ENCODING = new char[MAX_ENCODING - MIN_ENCODING + 1];
-    private static final int MIN_DECODING = '!';
-    private static final int MAX_DECODING = '}';
-    private static final char[] DECODING = new char[MAX_DECODING - MIN_DECODING + 1];
-
-    static {
-        addEncoding('/', '|');
-        addEncoding('.', ',');
-        addEncoding(';', '?');
-        addEncoding('$', '%');
-        addEncoding('<', '^');
-        addEncoding('>', '_');
-        addEncoding('[', '{');
-        addEncoding(']', '}');
-        addEncoding(':', '!');
-        addEncoding('\\', '-');
-        DECODING[EMPTY_ESCAPE - MIN_DECODING] = EMPTY_CHAR;
-    }
-
-    private NameCodec() {
-    }
-
-    /**
-     * Encodes ("mangles") an unencoded symbolic name.
-     * @param name the symbolic name to mangle
-     * @return the mangled form of the symbolic name.
-     */
-    public static String encode(final String name) {
-        final int l = name.length();
-        if(l == 0) {
-            return EMPTY_NAME;
-        }
-        StringBuilder b = null;
-        int lastEscape = -1;
-        for(int i = 0; i < l; ++i) {
-            final int encodeIndex = name.charAt(i) - MIN_ENCODING;
-            if(encodeIndex >= 0 && encodeIndex < ENCODING.length) {
-                final char e = ENCODING[encodeIndex];
-                if(e != 0) {
-                    if(b == null) {
-                        b = new StringBuilder(name.length() + 3);
-                        if(name.charAt(0) != ESCAPE_CHAR && i > 0) {
-                            b.append(EMPTY_NAME);
-                        }
-                        b.append(name, 0, i);
-                    } else {
-                        b.append(name, lastEscape + 1, i);
-                    }
-                    b.append(ESCAPE_CHAR).append(e);
-                    lastEscape = i;
-                }
-            }
-        }
-        if(b == null) {
-            return name;
-        }
-        assert lastEscape != -1;
-        b.append(name, lastEscape + 1, l);
-        return b.toString();
-    }
-
-    /**
-     * Decodes ("demangles") an encoded symbolic name.
-     * @param name the symbolic name to demangle
-     * @return the demangled form of the symbolic name.
-     */
-    public static String decode(final String name) {
-        if(name.isEmpty() || name.charAt(0) != ESCAPE_CHAR) {
-            return name;
-        }
-        final int l = name.length();
-        if(l == 2 && name.charAt(1) == EMPTY_CHAR) {
-            return "";
-        }
-        final StringBuilder b = new StringBuilder(name.length());
-        int lastEscape = -2;
-        int lastBackslash = -1;
-        for(;;) {
-            final int nextBackslash = name.indexOf(ESCAPE_CHAR, lastBackslash + 1);
-            if(nextBackslash == -1 || nextBackslash == l - 1) {
-                break;
-            }
-            final int decodeIndex = name.charAt(nextBackslash + 1) - MIN_DECODING;
-            if(decodeIndex >= 0 && decodeIndex < DECODING.length) {
-                final char d = DECODING[decodeIndex];
-                if(d == EMPTY_CHAR) {
-                    // "\=" is only valid at the beginning of a mangled string
-                    if(nextBackslash == 0) {
-                        lastEscape = 0;
-                    }
-                } else if(d != 0) {
-                    b.append(name, lastEscape + 2, nextBackslash).append(d);
-                    lastEscape = nextBackslash;
-                }
-            }
-            lastBackslash = nextBackslash;
-        }
-        b.append(name, lastEscape + 2, l);
-        return b.toString();
-    }
-
-    private static void addEncoding(final char from, final char to) {
-        ENCODING[from - MIN_ENCODING] = to;
-        DECODING[to - MIN_DECODING] = from;
-    }
-}

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Compiler.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/Compiler.java	Thu Nov 05 13:42:32 2015 -0800
@@ -49,7 +49,6 @@
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Consumer;
 import java.util.logging.Level;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.nashorn.internal.codegen.types.Type;
 import jdk.nashorn.internal.ir.Expression;
 import jdk.nashorn.internal.ir.FunctionNode;
@@ -66,6 +65,7 @@
 import jdk.nashorn.internal.runtime.ScriptObject;
 import jdk.nashorn.internal.runtime.ScriptRuntime;
 import jdk.nashorn.internal.runtime.Source;
+import jdk.nashorn.internal.runtime.linker.NameCodec;
 import jdk.nashorn.internal.runtime.logging.DebugLogger;
 import jdk.nashorn.internal.runtime.logging.Loggable;
 import jdk.nashorn.internal.runtime.logging.Logger;

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/MethodEmitter.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/MethodEmitter.java	Thu Nov 05 13:42:32 2015 -0800
@@ -69,6 +69,7 @@
 import static jdk.nashorn.internal.codegen.CompilerConstants.staticField;
 import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup;
 import static jdk.nashorn.internal.codegen.ObjectClassGenerator.PRIMITIVE_FIELD_TYPE;
+import static jdk.nashorn.internal.runtime.linker.NameCodec.EMPTY_NAME;
 import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_OPTIMISTIC;
 import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_PROGRAM_POINT_SHIFT;
 
@@ -79,7 +80,6 @@
 import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Map;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.internal.org.objectweb.asm.Handle;
 import jdk.internal.org.objectweb.asm.MethodVisitor;
 import jdk.nashorn.internal.codegen.ClassEmitter.Flag;
@@ -107,6 +107,7 @@
 import jdk.nashorn.internal.runtime.ScriptRuntime;
 import jdk.nashorn.internal.runtime.UnwarrantedOptimismException;
 import jdk.nashorn.internal.runtime.linker.Bootstrap;
+import jdk.nashorn.internal.runtime.linker.NameCodec;
 import jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor;
 import jdk.nashorn.internal.runtime.logging.DebugLogger;
 import jdk.nashorn.internal.runtime.options.Options;
@@ -125,8 +126,6 @@
  * including bytecode stack contents
  */
 public class MethodEmitter {
-    private static final String EMPTY_NAME = NameCodec.encode("");
-
     /** The ASM MethodVisitor we are plugged into */
     private final MethodVisitor method;
 

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/types/Type.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/types/Type.java	Thu Nov 05 13:42:32 2015 -0800
@@ -53,7 +53,6 @@
 import java.io.IOException;
 import java.io.Serializable;
 import java.lang.invoke.CallSite;
-import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
 import java.util.Collections;
@@ -246,7 +245,7 @@
      * @return Nashorn type
      */
     @SuppressWarnings("fallthrough")
-    static Type typeFor(final jdk.internal.org.objectweb.asm.Type itype) {
+    private static Type typeFor(final jdk.internal.org.objectweb.asm.Type itype) {
         switch (itype.getSort()) {
         case jdk.internal.org.objectweb.asm.Type.BOOLEAN:
             return BOOLEAN;
@@ -260,11 +259,13 @@
             if (Context.isStructureClass(itype.getClassName())) {
                 return SCRIPT_OBJECT;
             }
-            try {
-                return Type.typeFor(Class.forName(itype.getClassName()));
-            } catch(final ClassNotFoundException e) {
-                throw new AssertionError(e);
-            }
+            return cacheByName.computeIfAbsent(itype.getClassName(), (name) -> {
+                try {
+                    return Type.typeFor(Class.forName(name));
+                } catch(final ClassNotFoundException e) {
+                    throw new AssertionError(e);
+                }
+            });
         case jdk.internal.org.objectweb.asm.Type.VOID:
             return null;
         case jdk.internal.org.objectweb.asm.Type.ARRAY:
@@ -785,19 +786,10 @@
      * @return the Type representing this class
      */
     public static Type typeFor(final Class<?> clazz) {
-        final Type type = cache.get(clazz);
-        if(type != null) {
-            return type;
-        }
-        assert !clazz.isPrimitive() || clazz == void.class;
-        final Type newType;
-        if (clazz.isArray()) {
-            newType = new ArrayType(clazz);
-        } else {
-            newType = new ObjectType(clazz);
-        }
-        final Type existingType = cache.putIfAbsent(clazz, newType);
-        return existingType == null ? newType : existingType;
+        return cache.computeIfAbsent(clazz, (keyClass) -> {
+            assert !keyClass.isPrimitive() || keyClass == void.class;
+            return keyClass.isArray() ? new ArrayType(keyClass) : new ObjectType(keyClass);
+        });
     }
 
     @Override
@@ -902,6 +894,7 @@
 
     /** Mappings between java classes and their Type singletons */
     private static final ConcurrentMap<Class<?>, Type> cache = new ConcurrentHashMap<>();
+    private static final ConcurrentMap<String, Type> cacheByName = new ConcurrentHashMap<>();
 
     /**
      * This is the boolean singleton, used for all boolean types

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/debug/ASTWriter.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/debug/ASTWriter.java	Thu Nov 05 13:42:32 2015 -0800
@@ -55,6 +55,16 @@
  * see the flags --print-ast and --print-ast-lower
  */
 public final class ASTWriter {
+    private static final ClassValue<Field[]> accessibleFields = new ClassValue<Field[]>() {
+        @Override
+        protected Field[] computeValue(final Class<?> type) {
+            final Field[] fields = type.getDeclaredFields();
+            for(final Field f: fields) {
+                f.setAccessible(true);
+            }
+            return fields;
+        }
+    };
     /** Root node from which to start the traversal */
     private final Node root;
 
@@ -258,9 +268,8 @@
 
         while (iter.hasNext()) {
             final Class<?> c = iter.next();
-            for (final Field f : c.getDeclaredFields()) {
+            for (final Field f : accessibleFields.get(c)) {
                 try {
-                    f.setAccessible(true);
                     final Object child = f.get(node);
                     if (child == null) {
                         continue;

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/debug/NashornTextifier.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/debug/NashornTextifier.java	Thu Nov 05 13:42:32 2015 -0800
@@ -39,7 +39,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.internal.org.objectweb.asm.Attribute;
 import jdk.internal.org.objectweb.asm.Handle;
 import jdk.internal.org.objectweb.asm.Label;
@@ -50,6 +49,7 @@
 import jdk.internal.org.objectweb.asm.util.TraceSignatureVisitor;
 import jdk.nashorn.internal.runtime.ScriptEnvironment;
 import jdk.nashorn.internal.runtime.linker.Bootstrap;
+import jdk.nashorn.internal.runtime.linker.NameCodec;
 import jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor;
 
 /**

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/parser/Parser.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/parser/Parser.java	Thu Nov 05 13:42:32 2015 -0800
@@ -68,8 +68,6 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
-
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.nashorn.internal.codegen.CompilerConstants;
 import jdk.nashorn.internal.codegen.Namespace;
 import jdk.nashorn.internal.ir.AccessNode;
@@ -121,6 +119,7 @@
 import jdk.nashorn.internal.runtime.ScriptingFunctions;
 import jdk.nashorn.internal.runtime.Source;
 import jdk.nashorn.internal.runtime.Timing;
+import jdk.nashorn.internal.runtime.linker.NameCodec;
 import jdk.nashorn.internal.runtime.logging.DebugLogger;
 import jdk.nashorn.internal.runtime.logging.Loggable;
 import jdk.nashorn.internal.runtime.logging.Logger;

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/Context.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/Context.java	Thu Nov 05 13:42:32 2015 -0800
@@ -64,13 +64,14 @@
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.atomic.LongAdder;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
 import java.util.logging.Level;
-import javax.script.ScriptContext;
 import javax.script.ScriptEngine;
 import jdk.internal.org.objectweb.asm.ClassReader;
 import jdk.internal.org.objectweb.asm.ClassWriter;
@@ -525,6 +526,7 @@
 
     private static final ClassLoader myLoader = Context.class.getClassLoader();
     private static final StructureLoader sharedLoader;
+    private static final ConcurrentMap<String, Class<?>> structureClasses = new ConcurrentHashMap<>();
 
     /*package-private*/ @SuppressWarnings("static-method")
     ClassLoader getSharedLoader() {
@@ -1056,7 +1058,13 @@
         if (System.getSecurityManager() != null && !StructureLoader.isStructureClass(fullName)) {
             throw new ClassNotFoundException(fullName);
         }
-        return (Class<? extends ScriptObject>)Class.forName(fullName, true, sharedLoader);
+        return (Class<? extends ScriptObject>)structureClasses.computeIfAbsent(fullName, (name) -> {
+            try {
+                return Class.forName(name, true, sharedLoader);
+            } catch (final ClassNotFoundException e) {
+                throw new AssertionError(e);
+            }
+        });
     }
 
     /**

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/RecompilableScriptFunctionData.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/RecompilableScriptFunctionData.java	Thu Nov 05 13:42:32 2015 -0800
@@ -44,7 +44,6 @@
 import java.util.concurrent.LinkedBlockingDeque;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.nashorn.internal.codegen.Compiler;
 import jdk.nashorn.internal.codegen.Compiler.CompilationPhases;
 import jdk.nashorn.internal.codegen.CompilerConstants;
@@ -67,6 +66,7 @@
 import jdk.nashorn.internal.parser.Parser;
 import jdk.nashorn.internal.parser.Token;
 import jdk.nashorn.internal.parser.TokenType;
+import jdk.nashorn.internal.runtime.linker.NameCodec;
 import jdk.nashorn.internal.runtime.logging.DebugLogger;
 import jdk.nashorn.internal.runtime.logging.Loggable;
 import jdk.nashorn.internal.runtime.logging.Logger;

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/Bootstrap.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/Bootstrap.java	Thu Nov 05 13:42:32 2015 -0800
@@ -45,7 +45,6 @@
 import jdk.internal.dynalink.linker.LinkerServices;
 import jdk.internal.dynalink.linker.MethodTypeConversionStrategy;
 import jdk.internal.dynalink.linker.support.TypeUtilities;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.nashorn.api.scripting.JSObject;
 import jdk.nashorn.internal.codegen.CompilerConstants.Call;
 import jdk.nashorn.internal.lookup.MethodHandleFactory;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/NameCodec.java	Thu Nov 05 13:42:32 2015 -0800
@@ -0,0 +1,432 @@
+/*
+ * Copyright (c) 2010, 2013, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 jdk.nashorn.internal.runtime.linker;
+
+/**
+ * <p>
+ * Implements the name mangling and demangling as specified by John Rose's
+ * <a href="https://blogs.oracle.com/jrose/entry/symbolic_freedom_in_the_vm"
+ * target="_blank">"Symbolic Freedom in the VM"</a> article. Normally, you would
+ * mangle the names in the call sites as you're generating bytecode, and then
+ * demangle them when you receive them in bootstrap methods.
+ * </p>
+ * <p>
+ * This code is derived from sun.invoke.util.BytecodeName. Apart from subsetting that
+ * class, we don't want to create dependency between non-exported package from java.base
+ * to nashorn module.
+ * </p>
+ *
+ * <h3>Comment from BytecodeName class reproduced here:</h3>
+ *
+ * Includes universal mangling rules for the JVM.
+ *
+ * <h3>Avoiding Dangerous Characters </h3>
+ *
+ * <p>
+ * The JVM defines a very small set of characters which are illegal
+ * in name spellings.  We will slightly extend and regularize this set
+ * into a group of <cite>dangerous characters</cite>.
+ * These characters will then be replaced, in mangled names, by escape sequences.
+ * In addition, accidental escape sequences must be further escaped.
+ * Finally, a special prefix will be applied if and only if
+ * the mangling would otherwise fail to begin with the escape character.
+ * This happens to cover the corner case of the null string,
+ * and also clearly marks symbols which need demangling.
+ * </p>
+ * <p>
+ * Dangerous characters are the union of all characters forbidden
+ * or otherwise restricted by the JVM specification,
+ * plus their mates, if they are brackets
+ * (<code><big><b>[</b></big></code> and <code><big><b>]</b></big></code>,
+ * <code><big><b>&lt;</b></big></code> and <code><big><b>&gt;</b></big></code>),
+ * plus, arbitrarily, the colon character <code><big><b>:</b></big></code>.
+ * There is no distinction between type, method, and field names.
+ * This makes it easier to convert between mangled names of different
+ * types, since they do not need to be decoded (demangled).
+ * </p>
+ * <p>
+ * The escape character is backslash <code><big><b>\</b></big></code>
+ * (also known as reverse solidus).
+ * This character is, until now, unheard of in bytecode names,
+ * but traditional in the proposed role.
+ *
+ * </p>
+ * <h3> Replacement Characters </h3>
+ *
+ *
+ * <p>
+ * Every escape sequence is two characters
+ * (in fact, two UTF8 bytes) beginning with
+ * the escape character and followed by a
+ * <cite>replacement character</cite>.
+ * (Since the replacement character is never a backslash,
+ * iterated manglings do not double in size.)
+ * </p>
+ * <p>
+ * Each dangerous character has some rough visual similarity
+ * to its corresponding replacement character.
+ * This makes mangled symbols easier to recognize by sight.
+ * </p>
+ * <p>
+ * The dangerous characters are
+ * <code><big><b>/</b></big></code> (forward slash, used to delimit package components),
+ * <code><big><b>.</b></big></code> (dot, also a package delimiter),
+ * <code><big><b>;</b></big></code> (semicolon, used in signatures),
+ * <code><big><b>$</b></big></code> (dollar, used in inner classes and synthetic members),
+ * <code><big><b>&lt;</b></big></code> (left angle),
+ * <code><big><b>&gt;</b></big></code> (right angle),
+ * <code><big><b>[</b></big></code> (left square bracket, used in array types),
+ * <code><big><b>]</b></big></code> (right square bracket, reserved in this scheme for language use),
+ * and <code><big><b>:</b></big></code> (colon, reserved in this scheme for language use).
+ * Their replacements are, respectively,
+ * <code><big><b>|</b></big></code> (vertical bar),
+ * <code><big><b>,</b></big></code> (comma),
+ * <code><big><b>?</b></big></code> (question mark),
+ * <code><big><b>%</b></big></code> (percent),
+ * <code><big><b>^</b></big></code> (caret),
+ * <code><big><b>_</b></big></code> (underscore), and
+ * <code><big><b>{</b></big></code> (left curly bracket),
+ * <code><big><b>}</b></big></code> (right curly bracket),
+ * <code><big><b>!</b></big></code> (exclamation mark).
+ * In addition, the replacement character for the escape character itself is
+ * <code><big><b>-</b></big></code> (hyphen),
+ * and the replacement character for the null prefix is
+ * <code><big><b>=</b></big></code> (equal sign).
+ * </p>
+ * <p>
+ * An escape character <code><big><b>\</b></big></code>
+ * followed by any of these replacement characters
+ * is an escape sequence, and there are no other escape sequences.
+ * An equal sign is only part of an escape sequence
+ * if it is the second character in the whole string, following a backslash.
+ * Two consecutive backslashes do <em>not</em> form an escape sequence.
+ * </p>
+ * <p>
+ * Each escape sequence replaces a so-called <cite>original character</cite>
+ * which is either one of the dangerous characters or the escape character.
+ * A null prefix replaces an initial null string, not a character.
+ * </p>
+ * <p>
+ * All this implies that escape sequences cannot overlap and may be
+ * determined all at once for a whole string.  Note that a spelling
+ * string can contain <cite>accidental escapes</cite>, apparent escape
+ * sequences which must not be interpreted as manglings.
+ * These are disabled by replacing their leading backslash with an
+ * escape sequence (<code><big><b>\-</b></big></code>).  To mangle a string, three logical steps
+ * are required, though they may be carried out in one pass:
+ * </p>
+ * <ol>
+ *   <li>In each accidental escape, replace the backslash with an escape sequence
+ * (<code><big><b>\-</b></big></code>).</li>
+ *   <li>Replace each dangerous character with an escape sequence
+ * (<code><big><b>\|</b></big></code> for <code><big><b>/</b></big></code>, etc.).</li>
+ *   <li>If the first two steps introduced any change, <em>and</em>
+ * if the string does not already begin with a backslash, prepend a null prefix (<code><big><b>\=</b></big></code>).</li>
+ * </ol>
+ *
+ * To demangle a mangled string that begins with an escape,
+ * remove any null prefix, and then replace (in parallel)
+ * each escape sequence by its original character.
+ * <p>Spelling strings which contain accidental
+ * escapes <em>must</em> have them replaced, even if those
+ * strings do not contain dangerous characters.
+ * This restriction means that mangling a string always
+ * requires a scan of the string for escapes.
+ * But then, a scan would be required anyway,
+ * to check for dangerous characters.
+ *
+ * </p>
+ * <h3> Nice Properties </h3>
+ *
+ * <p>
+ * If a bytecode name does not contain any escape sequence,
+ * demangling is a no-op:  The string demangles to itself.
+ * Such a string is called <cite>self-mangling</cite>.
+ * Almost all strings are self-mangling.
+ * In practice, to demangle almost any name &ldquo;found in nature&rdquo;,
+ * simply verify that it does not begin with a backslash.
+ * </p>
+ * <p>
+ * Mangling is a one-to-one function, while demangling
+ * is a many-to-one function.
+ * A mangled string is defined as <cite>validly mangled</cite> if
+ * it is in fact the unique mangling of its spelling string.
+ * Three examples of invalidly mangled strings are <code><big><b>\=foo</b></big></code>,
+ * <code><big><b>\-bar</b></big></code>, and <code><big><b>baz\!</b></big></code>, which demangle to <code><big><b>foo</b></big></code>, <code><big><b>\bar</b></big></code>, and
+ * <code><big><b>baz\!</b></big></code>, but then remangle to <code><big><b>foo</b></big></code>, <code><big><b>\bar</b></big></code>, and <code><big><b>\=baz\-!</b></big></code>.
+ * If a language back-end or runtime is using mangled names,
+ * it should never present an invalidly mangled bytecode
+ * name to the JVM.  If the runtime encounters one,
+ * it should also report an error, since such an occurrence
+ * probably indicates a bug in name encoding which
+ * will lead to errors in linkage.
+ * However, this note does not propose that the JVM verifier
+ * detect invalidly mangled names.
+ * </p>
+ * <p>
+ * As a result of these rules, it is a simple matter to
+ * compute validly mangled substrings and concatenations
+ * of validly mangled strings, and (with a little care)
+ * these correspond to corresponding operations on their
+ * spelling strings.
+ * </p>
+ * <ul>
+ *   <li>Any prefix of a validly mangled string is also validly mangled,
+ * although a null prefix may need to be removed.</li>
+ *   <li>Any suffix of a validly mangled string is also validly mangled,
+ * although a null prefix may need to be added.</li>
+ *   <li>Two validly mangled strings, when concatenated,
+ * are also validly mangled, although any null prefix
+ * must be removed from the second string,
+ * and a trailing backslash on the first string may need escaping,
+ * if it would participate in an accidental escape when followed
+ * by the first character of the second string.</li>
+ * </ul>
+ * <p>If languages that include non-Java symbol spellings use this
+ * mangling convention, they will enjoy the following advantages:
+ * </p>
+ * <ul>
+ *   <li>They can interoperate via symbols they share in common.</li>
+ *   <li>Low-level tools, such as backtrace printers, will have readable displays.</li>
+ *   <li>Future JVM and language extensions can safely use the dangerous characters
+ * for structuring symbols, but will never interfere with valid spellings.</li>
+ *   <li>Runtimes and compilers can use standard libraries for mangling and demangling.</li>
+ *   <li>Occasional transliterations and name composition will be simple and regular,
+ * for classes, methods, and fields.</li>
+ *   <li>Bytecode names will continue to be compact.
+ * When mangled, spellings will at most double in length, either in
+ * UTF8 or UTF16 format, and most will not change at all.</li>
+ * </ul>
+ *
+ *
+ * <h3> Suggestions for Human Readable Presentations </h3>
+ *
+ *
+ * <p>
+ * For human readable displays of symbols,
+ * it will be better to present a string-like quoted
+ * representation of the spelling, because JVM users
+ * are generally familiar with such tokens.
+ * We suggest using single or double quotes before and after
+ * mangled symbols which are not valid Java identifiers,
+ * with quotes, backslashes, and non-printing characters
+ * escaped as if for literals in the Java language.
+ * </p>
+ * <p>
+ * For example, an HTML-like spelling
+ * <code><big><b>&lt;pre&gt;</b></big></code> mangles to
+ * <code><big><b>\^pre\_</b></big></code> and could
+ * display more cleanly as
+ * <code><big><b>'&lt;pre&gt;'</b></big></code>,
+ * with the quotes included.
+ * Such string-like conventions are <em>not</em> suitable
+ * for mangled bytecode names, in part because
+ * dangerous characters must be eliminated, rather
+ * than just quoted.  Otherwise internally structured
+ * strings like package prefixes and method signatures
+ * could not be reliably parsed.
+ * </p>
+ * <p>
+ * In such human-readable displays, invalidly mangled
+ * names should <em>not</em> be demangled and quoted,
+ * for this would be misleading.  Likewise, JVM symbols
+ * which contain dangerous characters (like dots in field
+ * names or brackets in method names) should not be
+ * simply quoted.  The bytecode names
+ * <code><big><b>\=phase\,1</b></big></code> and
+ * <code><big><b>phase.1</b></big></code> are distinct,
+ * and in demangled displays they should be presented as
+ * <code><big><b>'phase.1'</b></big></code> and something like
+ * <code><big><b>'phase'.1</b></big></code>, respectively.
+ * </p>
+ */
+public final class NameCodec {
+    private NameCodec() {
+    }
+
+    private static final char ESCAPE_C = '\\';
+    // empty escape sequence to avoid a null name or illegal prefix
+    private static final char NULL_ESCAPE_C = '=';
+    private static final String NULL_ESCAPE = ESCAPE_C+""+NULL_ESCAPE_C;
+
+    /**
+     * Canonical encoding for the empty name.
+     */
+    public static final String EMPTY_NAME =  new String(new char[] { ESCAPE_C, NULL_ESCAPE_C });
+
+    /**
+     * Encodes ("mangles") an unencoded symbolic name.
+     * @param name the symbolic name to mangle
+     * @return the mangled form of the symbolic name.
+     */
+    public static String encode(final String name) {
+        String bn = mangle(name);
+        assert((Object)bn == name || looksMangled(bn)) : bn;
+        assert(name.equals(decode(bn))) : name;
+        return bn;
+    }
+
+    /**
+     * Decodes ("demangles") an encoded symbolic name.
+     * @param name the symbolic name to demangle
+     * @return the demangled form of the symbolic name.
+     */
+    public static String decode(final String name) {
+        String sn = name;
+        if (!sn.isEmpty() && looksMangled(name)) {
+            sn = demangle(name);
+            assert(name.equals(mangle(sn))) : name+" => "+sn+" => "+mangle(sn);
+        }
+        return sn;
+    }
+
+    private static boolean looksMangled(String s) {
+        return s.charAt(0) == ESCAPE_C;
+    }
+
+    private static String mangle(String s) {
+        if (s.length() == 0)
+            return NULL_ESCAPE;
+
+        // build this lazily, when we first need an escape:
+        StringBuilder sb = null;
+
+        for (int i = 0, slen = s.length(); i < slen; i++) {
+            char c = s.charAt(i);
+
+            boolean needEscape = false;
+            if (c == ESCAPE_C) {
+                if (i+1 < slen) {
+                    char c1 = s.charAt(i+1);
+                    if ((i == 0 && c1 == NULL_ESCAPE_C)
+                        || c1 != originalOfReplacement(c1)) {
+                        // an accidental escape
+                        needEscape = true;
+                    }
+                }
+            } else {
+                needEscape = isDangerous(c);
+            }
+
+            if (!needEscape) {
+                if (sb != null)  sb.append(c);
+                continue;
+            }
+
+            // build sb if this is the first escape
+            if (sb == null) {
+                sb = new StringBuilder(s.length()+10);
+                // mangled names must begin with a backslash:
+                if (s.charAt(0) != ESCAPE_C && i > 0)
+                    sb.append(NULL_ESCAPE);
+                // append the string so far, which is unremarkable:
+                sb.append(s, 0, i);
+            }
+
+            // rewrite \ to \-, / to \|, etc.
+            sb.append(ESCAPE_C);
+            sb.append(replacementOf(c));
+        }
+
+        if (sb != null)   return sb.toString();
+
+        return s;
+    }
+
+    private static String demangle(String s) {
+        // build this lazily, when we first meet an escape:
+        StringBuilder sb = null;
+
+        int stringStart = 0;
+        if (s.startsWith(NULL_ESCAPE))
+            stringStart = 2;
+
+        for (int i = stringStart, slen = s.length(); i < slen; i++) {
+            char c = s.charAt(i);
+
+            if (c == ESCAPE_C && i+1 < slen) {
+                // might be an escape sequence
+                char rc = s.charAt(i+1);
+                char oc = originalOfReplacement(rc);
+                if (oc != rc) {
+                    // build sb if this is the first escape
+                    if (sb == null) {
+                        sb = new StringBuilder(s.length());
+                        // append the string so far, which is unremarkable:
+                        sb.append(s, stringStart, i);
+                    }
+                    ++i;  // skip both characters
+                    c = oc;
+                }
+            }
+
+            if (sb != null)
+                sb.append(c);
+        }
+
+        if (sb != null)   return sb.toString();
+
+        return s.substring(stringStart);
+    }
+
+    private static final String DANGEROUS_CHARS   = "\\/.;:$[]<>"; // \\ must be first
+    private static final String REPLACEMENT_CHARS =  "-|,?!%{}^_";
+    private static final int DANGEROUS_CHAR_FIRST_INDEX = 1; // index after \\
+
+    private static final long[] SPECIAL_BITMAP = new long[2];  // 128 bits
+    static {
+        String SPECIAL = DANGEROUS_CHARS + REPLACEMENT_CHARS;
+        for (char c : SPECIAL.toCharArray()) {
+            SPECIAL_BITMAP[c >>> 6] |= 1L << c;
+        }
+    }
+
+    private static boolean isSpecial(char c) {
+        if ((c >>> 6) < SPECIAL_BITMAP.length)
+            return ((SPECIAL_BITMAP[c >>> 6] >> c) & 1) != 0;
+        else
+            return false;
+    }
+
+    private static char replacementOf(char c) {
+        if (!isSpecial(c))  return c;
+        int i = DANGEROUS_CHARS.indexOf(c);
+        if (i < 0)  return c;
+        return REPLACEMENT_CHARS.charAt(i);
+    }
+
+    private static char originalOfReplacement(char c) {
+        if (!isSpecial(c))  return c;
+        int i = REPLACEMENT_CHARS.indexOf(c);
+        if (i < 0)  return c;
+        return DANGEROUS_CHARS.charAt(i);
+    }
+
+    private static boolean isDangerous(char c) {
+        if (!isSpecial(c))  return false;
+        return (DANGEROUS_CHARS.indexOf(c) >= DANGEROUS_CHAR_FIRST_INDEX);
+    }
+}

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/NashornCallSiteDescriptor.java	Thu Nov 05 08:15:48 2015 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/NashornCallSiteDescriptor.java	Thu Nov 05 13:42:32 2015 -0800
@@ -28,17 +28,22 @@
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodHandles.Lookup;
 import java.lang.invoke.MethodType;
+import java.lang.ref.Reference;
+import java.lang.ref.WeakReference;
 import java.security.AccessControlContext;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import java.util.Collections;
+import java.util.Map;
+import java.util.WeakHashMap;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
+import java.util.stream.Stream;
 import jdk.internal.dynalink.CallSiteDescriptor;
 import jdk.internal.dynalink.CompositeOperation;
 import jdk.internal.dynalink.NamedOperation;
 import jdk.internal.dynalink.Operation;
 import jdk.internal.dynalink.StandardOperation;
-import jdk.internal.dynalink.support.NameCodec;
 import jdk.nashorn.internal.ir.debug.NashornTextifier;
 import jdk.nashorn.internal.runtime.AccessControlContextFactory;
 import jdk.nashorn.internal.runtime.ScriptRuntime;
@@ -158,6 +163,11 @@
     private static final AccessControlContext GET_LOOKUP_PERMISSION_CONTEXT =
             AccessControlContextFactory.createAccessControlContext(CallSiteDescriptor.GET_LOOKUP_PERMISSION_NAME);
 
+    @SuppressWarnings("unchecked")
+    private static final Map<String, Reference<NamedOperation>>[] NAMED_OPERATIONS =
+            Stream.generate(() -> Collections.synchronizedMap(new WeakHashMap<>()))
+            .limit(OPERATIONS.length).toArray(Map[]::new);
+
     private final int flags;
 
     /**
@@ -218,19 +228,36 @@
      */
     public static NashornCallSiteDescriptor get(final MethodHandles.Lookup lookup, final String name,
             final MethodType methodType, final int flags) {
-        final Operation baseOp = OPERATIONS[flags & OPERATION_MASK];
+        final int opIndex = flags & OPERATION_MASK;
+        final Operation baseOp = OPERATIONS[opIndex];
         final String decodedName = NameCodec.decode(name);
-        // TODO: introduce caching of NamedOperation
-        final Operation op = decodedName.isEmpty() ? baseOp : new NamedOperation(baseOp, decodedName);
+        final Operation op = decodedName.isEmpty() ? baseOp : getNamedOperation(decodedName, opIndex, baseOp);
         return get(lookup, op, methodType, flags);
     }
 
+    private static NamedOperation getNamedOperation(final String name, final int opIndex, final Operation baseOp) {
+        final Map<String, Reference<NamedOperation>> namedOps = NAMED_OPERATIONS[opIndex];
+        final Reference<NamedOperation> ref = namedOps.get(name);
+        if (ref != null) {
+            final NamedOperation existing = ref.get();
+            if (existing != null) {
+                return existing;
+            }
+        }
+        final NamedOperation newOp = new NamedOperation(baseOp, name);
+        namedOps.put(name, new WeakReference<>(newOp));
+        return newOp;
+    }
+
     private static NashornCallSiteDescriptor get(final MethodHandles.Lookup lookup, final Operation operation, final MethodType methodType, final int flags) {
         final NashornCallSiteDescriptor csd = new NashornCallSiteDescriptor(lookup, operation, methodType, flags);
         // Many of these call site descriptors are identical (e.g. every getter for a property color will be
-        // "GET_PROPERTY:color(Object)Object", so it makes sense canonicalizing them.
-        final ConcurrentMap<NashornCallSiteDescriptor, NashornCallSiteDescriptor> classCanonicals = canonicals.get(lookup.lookupClass());
-        final NashornCallSiteDescriptor canonical = classCanonicals.putIfAbsent(csd, csd);
+        // "GET_PROPERTY:color(Object)Object", so it makes sense canonicalizing them. Make an exception for
+        // optimistic call site descriptors, as they also carry a program point making them unique.
+        if (csd.isOptimistic()) {
+            return csd;
+        }
+        final NashornCallSiteDescriptor canonical = canonicals.get(lookup.lookupClass()).putIfAbsent(csd, csd);
         return canonical != null ? canonical : csd;
     }
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/src/jdk/nashorn/internal/runtime/linker/test/NameCodecTest.java	Thu Nov 05 13:42:32 2015 -0800
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2015, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 jdk.nashorn.internal.runtime.linker.test;
+
+import static org.testng.Assert.assertEquals;
+
+import jdk.nashorn.internal.runtime.linker.NameCodec;
+import org.testng.annotations.Test;
+
+/**
+ * Test for jdk.nashorn.intenal.runtime.linker.NameCodec.java. This test is
+ * derived from BytecodeNameTest.java from (older) mlvm code @
+ * http://hg.openjdk.java.net/mlvm/mlvm/file/tip/netbeans/meth/test/sun/invoke/util/BytecodeNameTest.java
+ *
+ * @bug 8141285: NameCode should pass tests from BytecodeNameTest.java
+ */
+public class NameCodecTest {
+
+    static String[][] SAMPLES = {
+        // mangled, source
+        {"foo", "foo"},
+        {"ba\\r", "ba\\r"},
+        {"\\=ba\\-%z", "ba\\%z"},
+        {"\\=ba\\--z", "ba\\-z"},
+        {"=\\=", "=\\="},
+        {"\\==\\|\\=", "=/\\="},
+        {"\\|\\=", "/\\="},
+        {"\\=ba\\!", "ba:"},
+        {"\\|", "/"},
+        {"\\", "\\"},
+        {"\\\\%", "\\$"},
+        {"\\\\", "\\\\"},
+        {"\\=", ""}
+
+    };
+
+    static final String DANGEROUS_CHARS = "\\/.;:$[]<>";
+    static final String REPLACEMENT_CHARS = "-|,?!%{}^_";
+
+    static String[][] canonicalSamples() {
+        int ndc = DANGEROUS_CHARS.length();
+        String[][] res = new String[2 * ndc][];
+        for (int i = 0; i < ndc; i++) {
+            char dc = DANGEROUS_CHARS.charAt(i);
+            char rc = REPLACEMENT_CHARS.charAt(i);
+            if (dc == '\\') {
+                res[2 * i + 0] = new String[]{"\\-%", "\\%"};
+            } else {
+                res[2 * i + 0] = new String[]{"\\" + rc, "" + dc};
+            }
+            res[2 * i + 1] = new String[]{"" + rc, "" + rc};
+        }
+        return res;
+    }
+
+    @Test
+    public void testEncode() {
+        System.out.println("testEncode");
+        testEncode(SAMPLES);
+        testEncode(canonicalSamples());
+    }
+
+    private void testEncode(String[][] samples) {
+        for (String[] sample : samples) {
+            String s = sample[1];
+            String expResult = sample[0];
+            String result = NameCodec.encode(s);
+            if (!result.equals(expResult)) {
+                System.out.println(s + " => " + result + " != " + expResult);
+            }
+            assertEquals(expResult, result);
+        }
+    }
+
+    @Test
+    public void testDecode() {
+        System.out.println("testDecode");
+        testDecode(SAMPLES);
+        testDecode(canonicalSamples());
+    }
+
+    private void testDecode(String[][] samples) {
+        for (String[] sample : samples) {
+            String s = sample[0];
+            String expResult = sample[1];
+            String result = NameCodec.decode(s);
+            assertEquals(expResult, result);
+        }
+    }
+}