--- /dev/null	2020-01-02 04:43:18.583999853 +0000
+++ new/src/share/classes/jdk/jfr/internal/ASMToolkit.java	2020-01-30 06:26:01.570799763 +0000
@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2016, 2018, 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.jfr.internal;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintWriter;
+import java.util.List;
+
+import jdk.internal.org.objectweb.asm.ClassReader;
+import jdk.internal.org.objectweb.asm.MethodVisitor;
+import jdk.internal.org.objectweb.asm.Opcodes;
+import jdk.internal.org.objectweb.asm.Type;
+import jdk.internal.org.objectweb.asm.commons.Method;
+import jdk.internal.org.objectweb.asm.util.TraceClassVisitor;
+import jdk.jfr.ValueDescriptor;
+import jdk.jfr.internal.EventInstrumentation.FieldInfo;
+
+final class ASMToolkit {
+    private static Type TYPE_STRING = Type.getType(String.class);
+    private static Type Type_THREAD = Type.getType(Thread.class);
+    private static Type TYPE_CLASS = Type.getType(Class.class);
+
+    public static void invokeSpecial(MethodVisitor methodVisitor, String className, Method m) {
+        methodVisitor.visitMethodInsn(Opcodes.INVOKESPECIAL, className, m.getName(), m.getDescriptor(), false);
+    }
+
+    public static void invokeStatic(MethodVisitor methodVisitor, String className, Method m) {
+        methodVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, className, m.getName(), m.getDescriptor(), false);
+    }
+
+    public static void invokeVirtual(MethodVisitor methodVisitor, String className, Method m) {
+        methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, className, m.getName(), m.getDescriptor(), false);
+    }
+
+
+    public static Type toType(ValueDescriptor v) {
+        String typeName = v.getTypeName();
+
+        switch (typeName) {
+        case "byte":
+            return Type.BYTE_TYPE;
+        case "short":
+            return Type.SHORT_TYPE;
+        case "int":
+            return Type.INT_TYPE;
+        case "long":
+            return Type.LONG_TYPE;
+        case "double":
+            return Type.DOUBLE_TYPE;
+        case "float":
+            return Type.FLOAT_TYPE;
+        case "char":
+            return Type.CHAR_TYPE;
+        case "boolean":
+            return Type.BOOLEAN_TYPE;
+        case "java.lang.String":
+            return TYPE_STRING;
+        case "java.lang.Thread":
+            return Type_THREAD;
+        case "java.lang.Class":
+            return TYPE_CLASS;
+        }
+        // Add support for SettingControl?
+       throw new Error("Not a valid type " + v.getTypeName());
+    }
+
+    /**
+     * Converts "int" into "I" and "java.lang.String" into "Ljava/lang/String;"
+     *
+     * @param typeName
+     *            type
+     *
+     * @return descriptor
+     */
+    public static String getDescriptor(String typeName) {
+        if ("int".equals(typeName)) {
+            return "I";
+        }
+        if ("long".equals(typeName)) {
+            return "J";
+        }
+        if ("boolean".equals(typeName)) {
+            return "Z";
+        }
+        if ("float".equals(typeName)) {
+            return "F";
+        }
+        if ("double".equals(typeName)) {
+            return "D";
+        }
+        if ("short".equals(typeName)) {
+            return "S";
+        }
+        if ("char".equals(typeName)) {
+            return "C";
+        }
+        if ("byte".equals(typeName)) {
+            return "B";
+        }
+        String internal = getInternalName(typeName);
+        return Type.getObjectType(internal).getDescriptor();
+    }
+
+    /**
+     * Converts java.lang.String into java/lang/String
+     *
+     * @param className
+     *
+     * @return internal name
+     */
+    public static String getInternalName(String className) {
+        return className.replace(".", "/");
+    }
+
+    public static Method makeWriteMethod(List<FieldInfo> fields) {
+        StringBuilder sb = new StringBuilder();
+        sb.append("(");
+        for (FieldInfo v : fields) {
+            if (!v.fieldName.equals(EventInstrumentation.FIELD_EVENT_THREAD) && !v.fieldName.equals(EventInstrumentation.FIELD_STACK_TRACE)) {
+                sb.append(v.fieldDescriptor);
+            }
+        }
+        sb.append(")V");
+        return new Method("write", sb.toString());
+    }
+
+    public static void logASM(String className, byte[] bytes) {
+        Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.INFO, "Generated bytecode for class " + className);
+        Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.TRACE, () -> {
+            ClassReader cr = new ClassReader(bytes);
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            PrintWriter w = new PrintWriter(baos);
+            w.println("Bytecode:");
+            cr.accept(new TraceClassVisitor(w), 0);
+            return baos.toString();
+        });
+    }
+
+}