/*
 * Copyright (c) 2009, 2015, 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.nodes.calc;

import org.graalvm.compiler.core.common.calc.Condition;
import org.graalvm.compiler.core.common.type.FloatStamp;
import org.graalvm.compiler.core.common.type.Stamp;
import org.graalvm.compiler.core.common.type.StampFactory;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.NodeCycles;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodeinfo.NodeSize;
import org.graalvm.compiler.nodes.ConstantNode;
import org.graalvm.compiler.nodes.LogicConstantNode;
import org.graalvm.compiler.nodes.LogicNode;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.spi.Lowerable;
import org.graalvm.compiler.nodes.spi.LoweringTool;

import jdk.vm.ci.meta.ConstantReflectionProvider;
import jdk.vm.ci.meta.JavaKind;

Returns -1, 0, or 1 if either x < y, x == y, or x > y. If the comparison is undecided (one of the inputs is NaN), the result is 1 if isUnorderedLess is false and -1 if isUnorderedLess is true.
/** * Returns -1, 0, or 1 if either x &lt; y, x == y, or x &gt; y. If the comparison is undecided (one * of the inputs is NaN), the result is 1 if isUnorderedLess is false and -1 if isUnorderedLess is * true. */
@NodeInfo(cycles = NodeCycles.CYCLES_2, size = NodeSize.SIZE_4) public final class NormalizeCompareNode extends BinaryNode implements Lowerable { public static final NodeClass<NormalizeCompareNode> TYPE = NodeClass.create(NormalizeCompareNode.class); protected final boolean isUnorderedLess; public NormalizeCompareNode(ValueNode x, ValueNode y, boolean isUnorderedLess) { super(TYPE, StampFactory.forKind(JavaKind.Int), x, y); this.isUnorderedLess = isUnorderedLess; } public static ValueNode create(ValueNode x, ValueNode y, boolean isUnorderedLess, ConstantReflectionProvider constantReflection) { LogicNode result = CompareNode.tryConstantFold(Condition.EQ, x, y, constantReflection, false); if (result instanceof LogicConstantNode) { LogicConstantNode logicConstantNode = (LogicConstantNode) result; LogicNode resultLT = CompareNode.tryConstantFold(Condition.LT, x, y, constantReflection, isUnorderedLess); if (resultLT instanceof LogicConstantNode) { LogicConstantNode logicConstantNodeLT = (LogicConstantNode) resultLT; if (logicConstantNodeLT.getValue()) { return ConstantNode.forInt(-1); } else if (logicConstantNode.getValue()) { return ConstantNode.forInt(0); } else { return ConstantNode.forInt(1); } } } return new NormalizeCompareNode(x, y, isUnorderedLess); } @Override public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { // nothing to do return this; } @Override public boolean inferStamp() { return false; } @Override public void lower(LoweringTool tool) { LogicNode equalComp; LogicNode lessComp; if (getX().stamp() instanceof FloatStamp) { equalComp = graph().unique(FloatEqualsNode.create(getX(), getY(), tool.getConstantReflection())); lessComp = graph().unique(FloatLessThanNode.create(getX(), getY(), isUnorderedLess, tool.getConstantReflection())); } else { equalComp = graph().unique(IntegerEqualsNode.create(getX(), getY(), tool.getConstantReflection())); lessComp = graph().unique(IntegerLessThanNode.create(getX(), getY(), tool.getConstantReflection())); } ConditionalNode equalValue = graph().unique(new ConditionalNode(equalComp, ConstantNode.forInt(0, graph()), ConstantNode.forInt(1, graph()))); ConditionalNode value = graph().unique(new ConditionalNode(lessComp, ConstantNode.forInt(-1, graph()), equalValue)); replaceAtUsagesAndDelete(value); } @Override public Stamp foldStamp(Stamp stampX, Stamp stampY) { return stamp(); } }