--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jvmci/jdk.vm.ci.meta/src/jdk/vm/ci/meta/ConstantReflectionProvider.java	Thu Oct 08 17:28:41 2015 -0700
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2012, 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.
+ *
+ * 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.vm.ci.meta;
+
+import java.lang.invoke.MethodHandle;
+
+/**
+ * Reflection operations on values represented as {@linkplain JavaConstant constants}. All methods
+ * in this interface require the VM to access the actual object encapsulated in
+ * {@link JavaKind#Object object} constants. This access is not always possible, depending on kind
+ * of VM and the state that the VM is in. Therefore, all methods can return {@code null} at any
+ * time, to indicate that the result is not available at this point. The caller is responsible to
+ * check for {@code null} results and handle them properly, e.g., not perform an optimization.
+ */
+public interface ConstantReflectionProvider {
+
+    /**
+     * Compares two constants for equality. The equality relationship is symmetric. Returns
+     * {@link Boolean#TRUE true} if the two constants represent the same run time value,
+     * {@link Boolean#FALSE false} if they are different. Returns {@code null} if the constants
+     * cannot be compared at this point.
+     */
+    Boolean constantEquals(Constant x, Constant y);
+
+    /**
+     * Returns the length of the array constant. Returns {@code null} if the constant is not an
+     * array, or if the array length is not available at this point.
+     */
+    Integer readArrayLength(JavaConstant array);
+
+    /**
+     * Reads a value from the given array at the given index. Returns {@code null} if the constant
+     * is not an array, if the index is out of bounds, or if the value is not available at this
+     * point.
+     */
+    JavaConstant readArrayElement(JavaConstant array, int index);
+
+    /**
+     * Reads a value from the given array at the given index if it is a stable array. Returns
+     * {@code null} if the constant is not a stable array, if it is a default value, if the index is
+     * out of bounds, or if the value is not available at this point.
+     */
+    JavaConstant readConstantArrayElement(JavaConstant array, int index);
+
+    /**
+     * Reads a value from the given array at the given offset if it is a stable array. The offset
+     * will be decoded relative to the platform addressing into an index into the array. Returns
+     * {@code null} if the constant is not a stable array, if it is a default value, if the offset
+     * is out of bounds, or if the value is not available at this point.
+     */
+    JavaConstant readConstantArrayElementForOffset(JavaConstant array, long offset);
+
+    /**
+     * Gets the constant value of this field. Note that a {@code static final} field may not be
+     * considered constant if its declaring class is not yet initialized or if it is a well known
+     * field that can be updated via other means (e.g., {@link System#setOut(java.io.PrintStream)}).
+     *
+     * @param receiver object from which this field's value is to be read. This value is ignored if
+     *            this field is static.
+     * @return the constant value of this field or {@code null} if this field is not considered
+     *         constant by the runtime
+     */
+    JavaConstant readConstantFieldValue(JavaField field, JavaConstant receiver);
+
+    /**
+     * Gets the current value of this field for a given object, if available.
+     *
+     * There is no guarantee that the same value will be returned by this method for a field unless
+     * the field is considered to be {@linkplain #readConstantFieldValue(JavaField, JavaConstant)
+     * constant} by the runtime.
+     *
+     * @param receiver object from which this field's value is to be read. This value is ignored if
+     *            this field is static.
+     * @return the value of this field or {@code null} if the value is not available (e.g., because
+     *         the field holder is not yet initialized).
+     */
+    JavaConstant readFieldValue(JavaField field, JavaConstant receiver);
+
+    /**
+     * Gets the current value of this field for a given object, if available. Like
+     * {@link #readFieldValue(JavaField, JavaConstant)} but treats array fields as stable.
+     *
+     * There is no guarantee that the same value will be returned by this method for a field unless
+     * the field is considered to be {@linkplain #readConstantFieldValue(JavaField, JavaConstant)
+     * constant} by the runtime.
+     *
+     * @param receiver object from which this field's value is to be read. This value is ignored if
+     *            this field is static.
+     * @param isDefaultStable if {@code true}, default values are considered stable
+     * @return the value of this field or {@code null} if the value is not available (e.g., because
+     *         the field holder is not yet initialized).
+     */
+    JavaConstant readStableFieldValue(JavaField field, JavaConstant receiver, boolean isDefaultStable);
+
+    /**
+     * Converts the given {@link JavaKind#isPrimitive() primitive} constant to a boxed
+     * {@link JavaKind#Object object} constant, according to the Java boxing rules. Returns
+     * {@code null} if the source is is not a primitive constant, or the boxed value is not
+     * available at this point.
+     */
+    JavaConstant boxPrimitive(JavaConstant source);
+
+    /**
+     * Converts the given {@link JavaKind#Object object} constant to a
+     * {@link JavaKind#isPrimitive() primitive} constant, according to the Java unboxing rules.
+     * Returns {@code null} if the source is is not an object constant that can be unboxed, or the
+     * unboxed value is not available at this point.
+     */
+    JavaConstant unboxPrimitive(JavaConstant source);
+
+    /**
+     * Gets a string as a {@link JavaConstant}.
+     */
+    JavaConstant forString(String value);
+
+    /**
+     * Boxes a raw object as a {@link JavaConstant}. May return {@code null} if the object can not
+     * be transferred from the compiler VM to the runtime VM.
+     */
+    JavaConstant forObject(Object value);
+
+    /**
+     * Returns the {@link ResolvedJavaType} for a {@link Class} object (or any other object regarded
+     * as a class by the VM) encapsulated in the given constant. Returns {@code null} if the
+     * constant does not encapsulate a class, or if the type is not available at this point.
+     */
+    ResolvedJavaType asJavaType(Constant constant);
+
+    /**
+     * Gets access to the internals of {@link MethodHandle}.
+     */
+    MethodHandleAccessProvider getMethodHandleAccess();
+
+    /**
+     * Gets raw memory access.
+     */
+    MemoryAccessProvider getMemoryAccessProvider();
+}