/*

 * Copyright (c) 2014, 2019, 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

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package org.graalvm.compiler.nodes.calc;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2;

import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2;

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

import org.graalvm.compiler.core.common.type.ArithmeticOpTable.BinaryOp.MulHigh;

import org.graalvm.compiler.graph.NodeClass;

import org.graalvm.compiler.graph.spi.Canonicalizable;

import org.graalvm.compiler.graph.spi.CanonicalizerTool;

import org.graalvm.compiler.lir.gen.ArithmeticLIRGeneratorTool;

import org.graalvm.compiler.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.ConstantNode;

import org.graalvm.compiler.nodes.NodeView;

import org.graalvm.compiler.nodes.ValueNode;

import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;

import jdk.vm.ci.meta.Constant;

import jdk.vm.ci.meta.PrimitiveConstant;

import jdk.vm.ci.meta.Value;

@NodeInfo(shortName = "*H", cycles = CYCLES_2, size = SIZE_2)

public final class IntegerMulHighNode extends BinaryArithmeticNode<MulHigh> implements Canonicalizable.BinaryCommutative<ValueNode> {

    public static final NodeClass<IntegerMulHighNode> TYPE = NodeClass.create(IntegerMulHighNode.class);

    public IntegerMulHighNode(ValueNode x, ValueNode y) {

    }

    @Override

    public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {

        Value a = nodeValueMap.operand(getX());

        Value b = nodeValueMap.operand(getY());

        nodeValueMap.setResult(this, gen.emitMulHigh(a, b));

    }

    @Override

    public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) {

        ValueNode ret = super.canonical(tool, forX, forY);

        if (ret != this) {

            return ret;

        }

        if (forX.isConstant() && !forY.isConstant()) {

            // we try to swap and canonicalize

            ValueNode improvement = canonical(tool, forY, forX);

            if (improvement != this) {

                return improvement;

            }

            // if this fails we only swap

            return new IntegerMulHighNode(forY, forX);

        }

        return canonical(this, forY);

    }

    private static ValueNode canonical(IntegerMulHighNode self, ValueNode forY) {

        if (forY.isConstant()) {

            Constant c = forY.asConstant();

            if (c instanceof PrimitiveConstant && ((PrimitiveConstant) c).getJavaKind().isNumericInteger()) {

                long i = ((PrimitiveConstant) c).asLong();

                if (i == 0 || i == 1) {

                    return ConstantNode.forIntegerStamp(self.stamp(NodeView.DEFAULT), 0);

                }

            }

        }

        return self;

    }

}