| /* |
| * Copyright (c) 2013, 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 org.graalvm.compiler.phases.verify; |
| |
| import org.graalvm.compiler.core.common.type.ObjectStamp; |
| import org.graalvm.compiler.nodes.ParameterNode; |
| import org.graalvm.compiler.nodes.StructuredGraph; |
| import org.graalvm.compiler.nodes.ValueNode; |
| import org.graalvm.compiler.nodes.calc.ObjectEqualsNode; |
| import org.graalvm.compiler.nodes.type.StampTool; |
| import org.graalvm.compiler.phases.VerifyPhase; |
| import org.graalvm.compiler.phases.tiers.PhaseContext; |
| |
| import jdk.vm.ci.meta.JavaField; |
| import jdk.vm.ci.meta.JavaKind; |
| import jdk.vm.ci.meta.JavaMethod; |
| import jdk.vm.ci.meta.JavaType; |
| import jdk.vm.ci.meta.MetaAccessProvider; |
| import jdk.vm.ci.meta.ResolvedJavaMethod; |
| import jdk.vm.ci.meta.ResolvedJavaType; |
| import jdk.vm.ci.meta.Signature; |
| |
| /** |
| * For certain types, object identity should not be used for object equality check. This phase |
| * checks the correct usage of the given type. Equality checks with == or != (except null checks) |
| * results in an {@link AssertionError}. |
| */ |
| public class VerifyUsageWithEquals extends VerifyPhase<PhaseContext> { |
| |
| @Override |
| public boolean checkContract() { |
| return false; |
| } |
| |
| /** |
| * The type of values that must not use identity for testing object equality. |
| */ |
| private final Class<?> restrictedClass; |
| |
| public VerifyUsageWithEquals(Class<?> restrictedClass) { |
| this.restrictedClass = restrictedClass; |
| assert !restrictedClass.isInterface() || isTrustedInterface(restrictedClass); |
| } |
| |
| private static final Class<?>[] trustedInterfaceTypes = {JavaType.class, JavaField.class, JavaMethod.class}; |
| |
| private static boolean isTrustedInterface(Class<?> cls) { |
| for (Class<?> trusted : trustedInterfaceTypes) { |
| if (trusted.isAssignableFrom(cls)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Determines whether the type of {@code node} is assignable to the {@link #restrictedClass}. |
| */ |
| private boolean isAssignableToRestrictedType(ValueNode node, MetaAccessProvider metaAccess) { |
| if (node.stamp() instanceof ObjectStamp) { |
| ResolvedJavaType restrictedType = metaAccess.lookupJavaType(restrictedClass); |
| ResolvedJavaType nodeType = StampTool.typeOrNull(node); |
| |
| if (nodeType != null && restrictedType.isAssignableFrom(nodeType)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| private static boolean isNullConstant(ValueNode node) { |
| return node.isConstant() && node.isNullConstant(); |
| } |
| |
| private static boolean isEqualsMethod(ResolvedJavaMethod method) { |
| if (method.getName().equals("equals")) { |
| Signature sig = method.getSignature(); |
| if (sig.getReturnKind() == JavaKind.Boolean) { |
| if (sig.getParameterCount(false) == 1) { |
| ResolvedJavaType ptype = (ResolvedJavaType) sig.getParameterType(0, method.getDeclaringClass()); |
| if (ptype.isJavaLangObject()) { |
| return true; |
| } |
| |
| } |
| } |
| } |
| return false; |
| } |
| |
| private static boolean isThisParameter(ValueNode node) { |
| return node instanceof ParameterNode && ((ParameterNode) node).index() == 0; |
| } |
| |
| /** |
| * Checks whether the type of {@code x} is assignable to the restricted type and that {@code y} |
| * is not a null constant. |
| */ |
| private boolean isIllegalUsage(ResolvedJavaMethod method, ValueNode x, ValueNode y, MetaAccessProvider metaAccess) { |
| if (isAssignableToRestrictedType(x, metaAccess) && !isNullConstant(y)) { |
| if (isEqualsMethod(method) && isThisParameter(x) || isThisParameter(y)) { |
| return false; |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| @Override |
| protected boolean verify(StructuredGraph graph, PhaseContext context) { |
| for (ObjectEqualsNode cn : graph.getNodes().filter(ObjectEqualsNode.class)) { |
| // bail out if we compare an object of type klass with == or != (except null checks) |
| ResolvedJavaMethod method = graph.method(); |
| ResolvedJavaType restrictedType = context.getMetaAccess().lookupJavaType(restrictedClass); |
| |
| if (method.getDeclaringClass().equals(restrictedType)) { |
| // Allow violation in methods of the restricted type itself. |
| } else if (isIllegalUsage(method, cn.getX(), cn.getY(), context.getMetaAccess()) || isIllegalUsage(method, cn.getY(), cn.getX(), context.getMetaAccess())) { |
| throw new VerificationError("Verification of " + restrictedClass.getName() + " usage failed: Comparing " + cn.getX() + " and " + cn.getY() + " in " + method + |
| " must use .equals() for object equality, not '==' or '!='"); |
| } |
| } |
| return true; |
| } |
| } |