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 * 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.
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package org.graalvm.compiler.hotspot.replacements;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1;

import org.graalvm.compiler.core.common.GraalOptions;
import org.graalvm.compiler.core.common.type.StampFactory;
import org.graalvm.compiler.core.common.type.TypeReference;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.Canonicalizable;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.hotspot.word.KlassPointer;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.ConstantNode;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.calc.ConvertNode;
import org.graalvm.compiler.nodes.calc.FloatingNode;
import org.graalvm.compiler.nodes.extended.HubGetClassNodeInterface;
import org.graalvm.compiler.nodes.spi.Lowerable;

import jdk.vm.ci.meta.Constant;
import jdk.vm.ci.meta.ConstantReflectionProvider;
import jdk.vm.ci.meta.JavaConstant;
import jdk.vm.ci.meta.MetaAccessProvider;
import jdk.vm.ci.meta.ResolvedJavaType;

Read Klass::_java_mirror and incorporate non-null type information into stamp. This is also used by ClassGetHubNode to eliminate chains of klass._java_mirror._klass.
/** * Read {@code Klass::_java_mirror} and incorporate non-null type information into stamp. This is * also used by {@link ClassGetHubNode} to eliminate chains of {@code klass._java_mirror._klass}. */
@NodeInfo(cycles = CYCLES_1, size = SIZE_1) public final class HubGetClassNode extends FloatingNode implements Lowerable, Canonicalizable, ConvertNode, HubGetClassNodeInterface { public static final NodeClass<HubGetClassNode> TYPE = NodeClass.create(HubGetClassNode.class); @Input protected ValueNode hub; public HubGetClassNode(@InjectedNodeParameter MetaAccessProvider metaAccess, ValueNode hub) { super(TYPE, StampFactory.objectNonNull(TypeReference.createWithoutAssumptions(metaAccess.lookupJavaType(Class.class)))); this.hub = hub; } @Override public ValueNode getHub() { return hub; } @Override public Node canonical(CanonicalizerTool tool) { if (tool.allUsagesAvailable() && hasNoUsages()) { return null; } else { MetaAccessProvider metaAccess = tool.getMetaAccess(); if (metaAccess != null && hub.isConstant() && !GraalOptions.ImmutableCode.getValue(tool.getOptions())) { ResolvedJavaType exactType = tool.getConstantReflection().asJavaType(hub.asConstant()); if (exactType != null) { return ConstantNode.forConstant(tool.getConstantReflection().asJavaClass(exactType), metaAccess); } } return this; } } @NodeIntrinsic public static native Class<?> readClass(KlassPointer hub); @Override public ValueNode getValue() { return hub; } @Override public Constant convert(Constant c, ConstantReflectionProvider constantReflection) { if (JavaConstant.NULL_POINTER.equals(c)) { return c; } return constantReflection.asJavaClass(constantReflection.asJavaType(c)); } @Override public Constant reverse(Constant c, ConstantReflectionProvider constantReflection) { if (JavaConstant.NULL_POINTER.equals(c)) { return c; } ResolvedJavaType type = constantReflection.asJavaType(c); if (type.isPrimitive()) { return JavaConstant.NULL_POINTER; } else { return constantReflection.asObjectHub(type); } }
Any concrete Klass* has a corresponding Class.
/** * Any concrete Klass* has a corresponding {@link java.lang.Class}. */
@Override public boolean isLossless() { return true; } @Override public boolean mayNullCheckSkipConversion() { return true; } }