hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.word/src/org/graalvm/word/PointerUtils.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.word/src/org/graalvm/word/PointerUtils.java Mon Jun 19 16:31:43 2017 -0700
@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2015, 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 org.graalvm.word;
+
+/**
+ * Utility methods on Pointers.
+ */
+public final class PointerUtils {
+
+ private PointerUtils() {
+ // This is a class of static methods, so no need for any instances.
+ }
+
+ /**
+ * The value of a null Pointer.
+ *
+ * @return A null Pointer value.
+ */
+ @SuppressWarnings("unchecked")
+ public static <T extends PointerBase> T nullPointer() {
+ return (T) WordFactory.zero();
+ }
+
+ /**
+ * Predicate to check for the null Pointer value.
+ *
+ * @return Whether that Pointer is the null Pointer.
+ */
+ public static boolean isNull(ComparableWord that) {
+ return that.equal(nullPointer());
+ }
+
+ /**
+ * Predicate to check for a non-null Pointer value.
+ *
+ * @return Whether that Pointer is not the null Pointer.
+ */
+ public static boolean isNonNull(ComparableWord that) {
+ return that.notEqual(nullPointer());
+ }
+
+ /**
+ * Round a Pointer down to the nearest smaller multiple.
+ *
+ * @param that The Pointer to be rounded up.
+ * @param multiple The multiple to which that Pointer should be decreased.
+ * @return That Pointer, but rounded down.
+ */
+ public static Pointer roundDown(PointerBase that, Unsigned multiple) {
+ return (Pointer) UnsignedUtils.roundDown((Unsigned) that, multiple);
+ }
+
+ /**
+ * Round a Pointer up to the nearest larger multiple.
+ *
+ * @param that The Pointer to be rounded up.
+ * @param multiple The multiple to which that Pointer should be increased.
+ * @return That Pointer, but rounded up.
+ */
+ public static Pointer roundUp(PointerBase that, Unsigned multiple) {
+ return (Pointer) UnsignedUtils.roundUp((Unsigned) that, multiple);
+ }
+
+ /**
+ * Check that a Pointer is an even multiple.
+ *
+ * @param that The Pointer to be verified as a multiple.
+ * @param multiple The multiple against which the Pointer should be verified.
+ * @return true if that Pointer is a multiple, false otherwise.
+ */
+ public static boolean isAMultiple(PointerBase that, Unsigned multiple) {
+ return that.equal(PointerUtils.roundDown(that, multiple));
+ }
+
+ /**
+ * Return the distance between two Pointers.
+ *
+ * @param pointer1 A first Pointer.
+ * @param pointer2 A second Pointer.
+ * @return The distance in bytes between the two Pointers.
+ */
+ public static Unsigned absoluteDifference(PointerBase pointer1, PointerBase pointer2) {
+ Pointer p1 = (Pointer) pointer1;
+ Pointer p2 = (Pointer) pointer2;
+ final Unsigned result;
+ if (p1.aboveOrEqual(p2)) {
+ result = p1.subtract(p2);
+ } else {
+ result = p2.subtract(p1);
+ }
+ return result;
+ }
+
+ /**
+ * The minimum of two Pointers.
+ *
+ * @param x A Pointer.
+ * @param y Another Pointer.
+ * @return The whichever Pointer is smaller.
+ */
+ public static <T extends PointerBase> T min(T x, T y) {
+ return (((Pointer) x).belowOrEqual((Pointer) y)) ? x : y;
+ }
+
+ /**
+ * The maximum of two Pointers.
+ *
+ * @param x A Pointer.
+ * @param y Another Pointer.
+ * @return The whichever Pointer is larger.
+ */
+ public static <T extends PointerBase> T max(T x, T y) {
+ return (((Pointer) x).aboveOrEqual((Pointer) y)) ? x : y;
+ }
+}