Mercurial > hg > truffle
view graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/phases/LoadJavaMirrorWithKlassPhase.java @ 15018:db4254246f9a
Remove Constant.forObject and Constant.asObject to improve compiler/VM separation
author | Christian Wimmer <christian.wimmer@oracle.com> |
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date | Mon, 07 Apr 2014 16:09:17 -0700 |
parents | f2b300c6e621 |
children | 2c0cfbf454b5 |
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/* * Copyright (c) 2013, 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 com.oracle.graal.hotspot.phases; import static com.oracle.graal.api.meta.LocationIdentity.*; import static com.oracle.graal.nodes.ConstantNode.*; import com.oracle.graal.api.meta.*; import com.oracle.graal.hotspot.meta.*; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.extended.*; import com.oracle.graal.nodes.type.*; import com.oracle.graal.phases.*; import com.oracle.graal.phases.common.*; import com.oracle.graal.phases.tiers.*; /** * For AOT compilation we aren't allowed to use a {@link Class} reference ({@code javaMirror}) * directly. Instead the {@link Class} reference should be obtained from the {@code Klass} object. * The reason for this is, that in Class Data Sharing (CDS) a {@code Klass} object is mapped to a * fixed address in memory, but the {@code javaMirror} is not (which lives in the Java heap). * * Lowering can introduce new {@link ConstantNode}s containing a {@link Class} reference, thus this * phase must be applied after {@link LoweringPhase}. * * @see AheadOfTimeVerificationPhase */ public class LoadJavaMirrorWithKlassPhase extends BasePhase<PhaseContext> { private final int classMirrorOffset; public LoadJavaMirrorWithKlassPhase(int classMirrorOffset) { this.classMirrorOffset = classMirrorOffset; } private FloatingReadNode getClassConstantReplacement(StructuredGraph graph, PhaseContext context, Constant constant) { if (constant.getKind() == Kind.Object && HotSpotObjectConstant.asObject(constant) instanceof Class<?>) { MetaAccessProvider metaAccess = context.getMetaAccess(); ResolvedJavaType type = metaAccess.lookupJavaType((Class<?>) HotSpotObjectConstant.asObject(constant)); assert type instanceof HotSpotResolvedObjectType; Constant klass = ((HotSpotResolvedObjectType) type).klass(); ConstantNode klassNode = ConstantNode.forConstant(klass, metaAccess, graph); Stamp stamp = StampFactory.exactNonNull(metaAccess.lookupJavaType(Class.class)); LocationNode location = ConstantLocationNode.create(FINAL_LOCATION, Kind.Object, classMirrorOffset, graph); FloatingReadNode freadNode = graph.unique(new FloatingReadNode(klassNode, location, null, stamp)); return freadNode; } return null; } @Override protected void run(StructuredGraph graph, PhaseContext context) { for (ConstantNode node : getConstantNodes(graph)) { Constant constant = node.asConstant(); FloatingReadNode freadNode = getClassConstantReplacement(graph, context, constant); if (freadNode != null) { node.replace(graph, freadNode); } } } }