1 /* 2 * Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package org.graalvm.compiler.nodes.calc; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2; 27 28 import org.graalvm.compiler.core.common.type.IntegerStamp; 29 import org.graalvm.compiler.core.common.type.Stamp; 30 import org.graalvm.compiler.graph.NodeClass; 31 import org.graalvm.compiler.graph.spi.Canonicalizable.BinaryCommutative; 32 import org.graalvm.compiler.graph.spi.CanonicalizerTool; 33 import org.graalvm.compiler.nodeinfo.NodeInfo; 34 import org.graalvm.compiler.nodes.BinaryOpLogicNode; 35 import org.graalvm.compiler.nodes.LogicConstantNode; 36 import org.graalvm.compiler.nodes.ValueNode; 37 38 import jdk.vm.ci.meta.TriState; 39 40 /** 41 * This node will perform a "test" operation on its arguments. Its result is equivalent to the 42 * expression "(x & y) == 0", meaning that it will return true if (and only if) no bit is set in 43 * both x and y. 44 */ 45 @NodeInfo(cycles = CYCLES_2, size = SIZE_2) 46 public final class IntegerTestNode extends BinaryOpLogicNode implements BinaryCommutative<ValueNode> { 47 public static final NodeClass<IntegerTestNode> TYPE = NodeClass.create(IntegerTestNode.class); 48 49 public IntegerTestNode(ValueNode x, ValueNode y) { 50 super(TYPE, x, y); 51 } 52 53 @Override 54 public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { 55 if (forX.isConstant() && forY.isConstant()) { 56 return LogicConstantNode.forBoolean((forX.asJavaConstant().asLong() & forY.asJavaConstant().asLong()) == 0); 57 } 58 if (forX.stamp() instanceof IntegerStamp && forY.stamp() instanceof IntegerStamp) { 59 IntegerStamp xStamp = (IntegerStamp) forX.stamp(); 60 IntegerStamp yStamp = (IntegerStamp) forY.stamp(); 61 if ((xStamp.upMask() & yStamp.upMask()) == 0) { 62 return LogicConstantNode.tautology(); 63 } else if ((xStamp.downMask() & yStamp.downMask()) != 0) { 64 return LogicConstantNode.contradiction(); 65 } 66 } 67 return this; 68 } 69 70 @Override 71 public Stamp getSucceedingStampForX(boolean negated) { 72 Stamp xStampGeneric = this.getX().stamp(); 73 Stamp yStampGeneric = this.getY().stamp(); 74 return getSucceedingStamp(negated, xStampGeneric, yStampGeneric); 75 } 76 77 private static Stamp getSucceedingStamp(boolean negated, Stamp xStampGeneric, Stamp otherStampGeneric) { 78 if (xStampGeneric instanceof IntegerStamp && otherStampGeneric instanceof IntegerStamp) { 79 IntegerStamp xStamp = (IntegerStamp) xStampGeneric; 80 IntegerStamp otherStamp = (IntegerStamp) otherStampGeneric; 81 if (negated) { 82 if (Long.bitCount(otherStamp.upMask()) == 1) { 83 long newDownMask = xStamp.downMask() | otherStamp.upMask(); 84 if (xStamp.downMask() != newDownMask) { 85 return IntegerStamp.stampForMask(xStamp.getBits(), newDownMask, xStamp.upMask()).join(xStamp); 86 } 87 } 88 } else { 89 long restrictedUpMask = ((~otherStamp.downMask()) & xStamp.upMask()); 90 if (xStamp.upMask() != restrictedUpMask) { 91 return IntegerStamp.stampForMask(xStamp.getBits(), xStamp.downMask(), restrictedUpMask).join(xStamp); 92 } 93 } 94 } 95 return null; 96 } 97 98 @Override 99 public Stamp getSucceedingStampForY(boolean negated) { 100 Stamp xStampGeneric = this.getX().stamp(); 101 Stamp yStampGeneric = this.getY().stamp(); 102 return getSucceedingStamp(negated, yStampGeneric, xStampGeneric); 103 } 104 105 @Override 106 public TriState tryFold(Stamp xStampGeneric, Stamp yStampGeneric) { 107 if (xStampGeneric instanceof IntegerStamp && yStampGeneric instanceof IntegerStamp) { 108 IntegerStamp xStamp = (IntegerStamp) xStampGeneric; 109 IntegerStamp yStamp = (IntegerStamp) yStampGeneric; 110 if ((xStamp.upMask() & yStamp.upMask()) == 0) { 111 return TriState.TRUE; 112 } else if ((xStamp.downMask() & yStamp.downMask()) != 0) { 113 return TriState.FALSE; 114 } 115 } 116 return TriState.UNKNOWN; 117 } 118 }