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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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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 java.nio.ByteBuffer;

import org.graalvm.compiler.core.common.type.IntegerStamp;
import org.graalvm.compiler.core.common.type.Stamp;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.Canonicalizable.BinaryCommutative;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.BinaryOpLogicNode;
import org.graalvm.compiler.nodes.LogicConstantNode;
import org.graalvm.compiler.nodes.LogicNode;
import org.graalvm.compiler.nodes.NodeView;
import org.graalvm.compiler.nodes.ValueNode;

import jdk.vm.ci.meta.TriState;

This node will perform a "test" operation on its arguments. Its result is equivalent to the expression "(x & y) == 0", meaning that it will return true if (and only if) no bit is set in both x and y.
/** * This node will perform a "test" operation on its arguments. Its result is equivalent to the * expression "(x & y) == 0", meaning that it will return true if (and only if) no bit is set in * both x and y. */
@NodeInfo(cycles = CYCLES_2, size = SIZE_2) public final class IntegerTestNode extends BinaryOpLogicNode implements BinaryCommutative<ValueNode> { public static final NodeClass<IntegerTestNode> TYPE = NodeClass.create(IntegerTestNode.class); public IntegerTestNode(ValueNode x, ValueNode y) { super(TYPE, x, y); } public static LogicNode create(ValueNode x, ValueNode y, NodeView view) { LogicNode value = canonical(x, y, view); if (value != null) { return value; } return new IntegerTestNode(x, y); } private static LogicNode canonical(ValueNode forX, ValueNode forY, NodeView view) { if (forX.isConstant() && forY.isConstant()) { if (forX.isJavaConstant() && forY.isJavaConstant()) { return LogicConstantNode.forBoolean((forX.asJavaConstant().asLong() & forY.asJavaConstant().asLong()) == 0); } if (forX.isSerializableConstant() && forY.isSerializableConstant()) { int bufSize = Math.min(forX.asSerializableConstant().getSerializedSize(), forX.asSerializableConstant().getSerializedSize()); ByteBuffer xBuf = ByteBuffer.allocate(bufSize); ByteBuffer yBuf = ByteBuffer.allocate(bufSize); forX.asSerializableConstant().serialize(xBuf); forY.asSerializableConstant().serialize(yBuf); return serializableToConst(xBuf, yBuf, bufSize); } } if (forX.stamp(view) instanceof IntegerStamp && forY.stamp(view) instanceof IntegerStamp) { IntegerStamp xStamp = (IntegerStamp) forX.stamp(view); IntegerStamp yStamp = (IntegerStamp) forY.stamp(view); if ((xStamp.upMask() & yStamp.upMask()) == 0) { return LogicConstantNode.tautology(); } else if ((xStamp.downMask() & yStamp.downMask()) != 0) { return LogicConstantNode.contradiction(); } } return null; } @Override public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { ValueNode value = canonical(forX, forY, NodeView.from(tool)); return value != null ? value : this; } private static LogicNode serializableToConst(ByteBuffer xBuf, ByteBuffer yBuf, int bufSize) { for (int i = 0; i < bufSize; i++) { if ((xBuf.get(i) & yBuf.get(i)) != 0) { return LogicConstantNode.contradiction(); } } return LogicConstantNode.tautology(); } @Override public Stamp getSucceedingStampForX(boolean negated, Stamp xStamp, Stamp yStamp) { return getSucceedingStamp(negated, xStamp, yStamp); } private static Stamp getSucceedingStamp(boolean negated, Stamp xStampGeneric, Stamp otherStampGeneric) { if (xStampGeneric instanceof IntegerStamp && otherStampGeneric instanceof IntegerStamp) { IntegerStamp xStamp = (IntegerStamp) xStampGeneric; IntegerStamp otherStamp = (IntegerStamp) otherStampGeneric; if (negated) { if (Long.bitCount(otherStamp.upMask()) == 1) { long newDownMask = xStamp.downMask() | otherStamp.upMask(); if (xStamp.downMask() != newDownMask) { return IntegerStamp.stampForMask(xStamp.getBits(), newDownMask, xStamp.upMask()).join(xStamp); } } } else { long restrictedUpMask = ((~otherStamp.downMask()) & xStamp.upMask()); if (xStamp.upMask() != restrictedUpMask) { return IntegerStamp.stampForMask(xStamp.getBits(), xStamp.downMask(), restrictedUpMask).join(xStamp); } } } return null; } @Override public Stamp getSucceedingStampForY(boolean negated, Stamp xStamp, Stamp yStamp) { return getSucceedingStamp(negated, yStamp, xStamp); } @Override public TriState tryFold(Stamp xStampGeneric, Stamp yStampGeneric) { if (xStampGeneric instanceof IntegerStamp && yStampGeneric instanceof IntegerStamp) { IntegerStamp xStamp = (IntegerStamp) xStampGeneric; IntegerStamp yStamp = (IntegerStamp) yStampGeneric; if ((xStamp.upMask() & yStamp.upMask()) == 0) { return TriState.TRUE; } else if ((xStamp.downMask() & yStamp.downMask()) != 0) { return TriState.FALSE; } } return TriState.UNKNOWN; } }