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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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package org.graalvm.compiler.hotspot.meta;

import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.POINTER_EQ;

import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.POINTER_NE;

import static org.graalvm.compiler.nodes.ConstantNode.forBoolean;

import static jdk.internal.vm.compiler.word.LocationIdentity.any;

import org.graalvm.compiler.api.replacements.SnippetReflectionProvider;

import org.graalvm.compiler.bytecode.BridgeMethodUtils;

import org.graalvm.compiler.core.common.type.Stamp;

import org.graalvm.compiler.core.common.type.StampFactory;

import org.graalvm.compiler.debug.GraalError;

import org.graalvm.compiler.hotspot.nodes.LoadIndexedPointerNode;

import org.graalvm.compiler.hotspot.nodes.type.KlassPointerStamp;

import org.graalvm.compiler.hotspot.nodes.type.MetaspacePointerStamp;

import org.graalvm.compiler.hotspot.nodes.type.MethodPointerStamp;

import org.graalvm.compiler.hotspot.word.HotSpotOperation;

import org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode;

import org.graalvm.compiler.hotspot.word.PointerCastNode;

import org.graalvm.compiler.nodes.LogicNode;

import org.graalvm.compiler.nodes.NodeView;

import org.graalvm.compiler.nodes.ValueNode;

import org.graalvm.compiler.nodes.calc.ConditionalNode;

import org.graalvm.compiler.nodes.calc.IsNullNode;

import org.graalvm.compiler.nodes.calc.PointerEqualsNode;

import org.graalvm.compiler.nodes.extended.GuardingNode;

import org.graalvm.compiler.nodes.graphbuilderconf.GraphBuilderContext;

import org.graalvm.compiler.nodes.java.LoadIndexedNode;

import org.graalvm.compiler.nodes.memory.HeapAccess.BarrierType;

import org.graalvm.compiler.nodes.memory.ReadNode;

import org.graalvm.compiler.nodes.memory.address.AddressNode;

import org.graalvm.compiler.nodes.type.StampTool;

import org.graalvm.compiler.word.WordOperationPlugin;

import org.graalvm.compiler.word.WordTypes;

import jdk.internal.vm.compiler.word.LocationIdentity;

import jdk.vm.ci.meta.JavaKind;

import jdk.vm.ci.meta.ResolvedJavaMethod;

import jdk.vm.ci.meta.ResolvedJavaType;

/**

 * Extends {@link WordOperationPlugin} to handle {@linkplain HotSpotOperation HotSpot word

 * operations}.

 */

public class HotSpotWordOperationPlugin extends WordOperationPlugin {

    HotSpotWordOperationPlugin(SnippetReflectionProvider snippetReflection, WordTypes wordTypes) {

        super(snippetReflection, wordTypes);

    }

    @Override

    protected LoadIndexedNode createLoadIndexedNode(ValueNode array, ValueNode index, GuardingNode boundsCheck) {

        ResolvedJavaType arrayType = StampTool.typeOrNull(array);

        Stamp componentStamp = wordTypes.getWordStamp(arrayType.getComponentType());

        if (componentStamp instanceof MetaspacePointerStamp) {

            return new LoadIndexedPointerNode(componentStamp, array, index, boundsCheck);

        } else {

            return super.createLoadIndexedNode(array, index, boundsCheck);

        }

    }

    @Override

    public boolean handleInvoke(GraphBuilderContext b, ResolvedJavaMethod method, ValueNode[] args) {

        if (!wordTypes.isWordOperation(method)) {

            return false;

        }

        HotSpotOperation operation = BridgeMethodUtils.getAnnotation(HotSpotOperation.class, method);

        if (operation == null) {

            processWordOperation(b, args, wordTypes.getWordOperation(method, b.getMethod().getDeclaringClass()));

            return true;

        }

        processHotSpotWordOperation(b, method, args, operation);

        return true;

    }

    protected void processHotSpotWordOperation(GraphBuilderContext b, ResolvedJavaMethod method, ValueNode[] args, HotSpotOperation operation) {

        JavaKind returnKind = method.getSignature().getReturnKind();

        switch (operation.opcode()) {

            case POINTER_EQ:

            case POINTER_NE:

                assert args.length == 2;

                HotspotOpcode opcode = operation.opcode();

                ValueNode left = args[0];

                ValueNode right = args[1];

                assert left.stamp(NodeView.DEFAULT) instanceof MetaspacePointerStamp : left + " " + left.stamp(NodeView.DEFAULT);

                assert right.stamp(NodeView.DEFAULT) instanceof MetaspacePointerStamp : right + " " + right.stamp(NodeView.DEFAULT);

                assert opcode == POINTER_EQ || opcode == POINTER_NE;

                PointerEqualsNode comparison = b.add(new PointerEqualsNode(left, right));

                ValueNode eqValue = b.add(forBoolean(opcode == POINTER_EQ));

                ValueNode neValue = b.add(forBoolean(opcode == POINTER_NE));

                b.addPush(returnKind, ConditionalNode.create(comparison, eqValue, neValue, NodeView.DEFAULT));

                break;

            case IS_NULL:

                assert args.length == 1;

                ValueNode pointer = args[0];

                assert pointer.stamp(NodeView.DEFAULT) instanceof MetaspacePointerStamp;

                LogicNode isNull = b.add(IsNullNode.create(pointer));

                b.addPush(returnKind, ConditionalNode.create(isNull, b.add(forBoolean(true)), b.add(forBoolean(false)), NodeView.DEFAULT));

                break;

            case FROM_POINTER:

                assert args.length == 1;

                b.addPush(returnKind, new PointerCastNode(StampFactory.forKind(wordKind), args[0]));

                break;

            case TO_KLASS_POINTER:

                assert args.length == 1;

                b.addPush(returnKind, new PointerCastNode(KlassPointerStamp.klass(), args[0]));

                break;

            case TO_METHOD_POINTER:

                assert args.length == 1;

                b.addPush(returnKind, new PointerCastNode(MethodPointerStamp.method(), args[0]));

                break;

            case READ_KLASS_POINTER:

                assert args.length == 2 || args.length == 3;

                Stamp readStamp = KlassPointerStamp.klass();

                AddressNode address = makeAddress(b, args[0], args[1]);

                LocationIdentity location;

                if (args.length == 2) {

                    location = any();

                } else {

                    assert args[2].isConstant();

                    location = snippetReflection.asObject(LocationIdentity.class, args[2].asJavaConstant());

                }

                ReadNode read = b.add(new ReadNode(address, location, readStamp, BarrierType.NONE));

                b.push(returnKind, read);

                break;

            default:

                throw GraalError.shouldNotReachHere("unknown operation: " + operation.opcode());

        }

    }

}