| /* |
| * Copyright (c) 2014, 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 static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1; |
| |
| import org.graalvm.compiler.core.common.type.ArithmeticOpTable; |
| import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp; |
| import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.Narrow; |
| import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.SignExtend; |
| import org.graalvm.compiler.core.common.type.PrimitiveStamp; |
| import org.graalvm.compiler.graph.NodeClass; |
| 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.ValueNode; |
| import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; |
| |
| /** |
| * The {@code NarrowNode} converts an integer to a narrower integer. |
| */ |
| @NodeInfo(cycles = CYCLES_1) |
| public final class NarrowNode extends IntegerConvertNode<Narrow, SignExtend> { |
| |
| public static final NodeClass<NarrowNode> TYPE = NodeClass.create(NarrowNode.class); |
| |
| public NarrowNode(ValueNode input, int resultBits) { |
| this(input, PrimitiveStamp.getBits(input.stamp()), resultBits); |
| assert 0 < resultBits && resultBits <= PrimitiveStamp.getBits(input.stamp()); |
| } |
| |
| public NarrowNode(ValueNode input, int inputBits, int resultBits) { |
| super(TYPE, ArithmeticOpTable::getNarrow, ArithmeticOpTable::getSignExtend, inputBits, resultBits, input); |
| } |
| |
| public static ValueNode create(ValueNode input, int resultBits) { |
| return create(input, PrimitiveStamp.getBits(input.stamp()), resultBits); |
| } |
| |
| public static ValueNode create(ValueNode input, int inputBits, int resultBits) { |
| IntegerConvertOp<Narrow> signExtend = ArithmeticOpTable.forStamp(input.stamp()).getNarrow(); |
| ValueNode synonym = findSynonym(signExtend, input, inputBits, resultBits, signExtend.foldStamp(inputBits, resultBits, input.stamp())); |
| if (synonym != null) { |
| return synonym; |
| } else { |
| return new NarrowNode(input, inputBits, resultBits); |
| } |
| } |
| |
| @Override |
| public boolean isLossless() { |
| return false; |
| } |
| |
| @Override |
| public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) { |
| ValueNode ret = super.canonical(tool, forValue); |
| if (ret != this) { |
| return ret; |
| } |
| |
| if (forValue instanceof NarrowNode) { |
| // zzzzzzzz yyyyxxxx -(narrow)-> yyyyxxxx -(narrow)-> xxxx |
| // ==> zzzzzzzz yyyyxxxx -(narrow)-> xxxx |
| NarrowNode other = (NarrowNode) forValue; |
| return new NarrowNode(other.getValue(), other.getInputBits(), getResultBits()); |
| } else if (forValue instanceof IntegerConvertNode) { |
| // SignExtendNode or ZeroExtendNode |
| IntegerConvertNode<?, ?> other = (IntegerConvertNode<?, ?>) forValue; |
| if (other.getValue().getUsageCount() == 1 && other.getUsageCount() > 1) { |
| // Do not perform if this will introduce a new live value. |
| // If the original value's usage count is > 1, there is already another user. |
| // If the convert's usage count is <=1, it will be dead code eliminated. |
| return this; |
| } |
| if (getResultBits() == other.getInputBits()) { |
| // xxxx -(extend)-> yyyy xxxx -(narrow)-> xxxx |
| // ==> no-op |
| return other.getValue(); |
| } else if (getResultBits() < other.getInputBits()) { |
| // yyyyxxxx -(extend)-> zzzzzzzz yyyyxxxx -(narrow)-> xxxx |
| // ==> yyyyxxxx -(narrow)-> xxxx |
| return new NarrowNode(other.getValue(), other.getInputBits(), getResultBits()); |
| } else { |
| if (other instanceof SignExtendNode) { |
| // sxxx -(sign-extend)-> ssssssss sssssxxx -(narrow)-> sssssxxx |
| // ==> sxxx -(sign-extend)-> sssssxxx |
| return new SignExtendNode(other.getValue(), other.getInputBits(), getResultBits()); |
| } else if (other instanceof ZeroExtendNode) { |
| // xxxx -(zero-extend)-> 00000000 00000xxx -(narrow)-> 0000xxxx |
| // ==> xxxx -(zero-extend)-> 0000xxxx |
| return new ZeroExtendNode(other.getValue(), other.getInputBits(), getResultBits()); |
| } |
| } |
| } |
| return this; |
| } |
| |
| @Override |
| public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) { |
| nodeValueMap.setResult(this, gen.emitNarrow(nodeValueMap.operand(getValue()), getResultBits())); |
| } |
| } |