| /* |
| * Copyright (c) 2016, 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.hotspot.meta; |
| |
| import org.graalvm.compiler.core.common.spi.JavaConstantFieldProvider; |
| import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig; |
| |
| import jdk.vm.ci.hotspot.HotSpotResolvedJavaField; |
| import jdk.vm.ci.meta.MetaAccessProvider; |
| import jdk.vm.ci.meta.ResolvedJavaField; |
| import jdk.vm.ci.meta.ResolvedJavaType; |
| |
| /** |
| * Implements the default constant folding semantics for Java fields in the HotSpot VM. |
| */ |
| public class HotSpotConstantFieldProvider extends JavaConstantFieldProvider { |
| |
| private final GraalHotSpotVMConfig config; |
| |
| public HotSpotConstantFieldProvider(GraalHotSpotVMConfig config, MetaAccessProvider metaAccess) { |
| super(metaAccess); |
| this.config = config; |
| } |
| |
| @Override |
| protected boolean isStableField(ResolvedJavaField field, ConstantFieldTool<?> tool) { |
| if (!config.foldStableValues) { |
| return false; |
| } |
| if (field.isStatic() && !isStaticFieldConstant(field)) { |
| return false; |
| } |
| |
| if (((HotSpotResolvedJavaField) field).isStable()) { |
| return true; |
| } |
| return super.isStableField(field, tool); |
| } |
| |
| @Override |
| protected boolean isFinalField(ResolvedJavaField field, ConstantFieldTool<?> tool) { |
| if (field.isStatic() && !isStaticFieldConstant(field)) { |
| return false; |
| } |
| |
| return super.isFinalField(field, tool); |
| } |
| |
| private static final String SystemClassName = "Ljava/lang/System;"; |
| |
| protected boolean isStaticFieldConstant(ResolvedJavaField field) { |
| ResolvedJavaType declaringClass = field.getDeclaringClass(); |
| return declaringClass.isInitialized() && !declaringClass.getName().equals(SystemClassName); |
| } |
| } |