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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
 * accompanied this code).
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package org.graalvm.compiler.nodes.memory.address;

import org.graalvm.compiler.core.common.type.AbstractPointerStamp;
import org.graalvm.compiler.core.common.type.IntegerStamp;
import org.graalvm.compiler.core.common.type.PrimitiveStamp;
import org.graalvm.compiler.core.common.type.Stamp;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.Canonicalizable;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.InputType;
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.calc.AddNode;
import org.graalvm.compiler.nodes.calc.BinaryArithmeticNode;

import jdk.vm.ci.meta.JavaKind;

Represents an address that is composed of a base and an offset. The base can be either a JavaKind.Object, a word-sized integer or another pointer. The offset must be a word-sized integer.
/** * Represents an address that is composed of a base and an offset. The base can be either a * {@link JavaKind#Object}, a word-sized integer or another pointer. The offset must be a word-sized * integer. */
@NodeInfo(allowedUsageTypes = InputType.Association) public class OffsetAddressNode extends AddressNode implements Canonicalizable { public static final NodeClass<OffsetAddressNode> TYPE = NodeClass.create(OffsetAddressNode.class); @Input ValueNode base; @Input ValueNode offset; public OffsetAddressNode(ValueNode base, ValueNode offset) { super(TYPE); this.base = base; this.offset = offset; assert base != null && (base.stamp(NodeView.DEFAULT) instanceof AbstractPointerStamp || IntegerStamp.getBits(base.stamp(NodeView.DEFAULT)) == 64) && offset != null && IntegerStamp.getBits(offset.stamp(NodeView.DEFAULT)) == 64 : "both values must have 64 bits"; } public static OffsetAddressNode create(ValueNode base) { ValueNode offset; if (base.stamp(NodeView.DEFAULT) instanceof AbstractPointerStamp) { offset = ConstantNode.forIntegerBits(64, 0); } else { offset = ConstantNode.forIntegerBits(PrimitiveStamp.getBits(base.stamp(NodeView.DEFAULT)), 0); } return new OffsetAddressNode(base, offset); } @Override public ValueNode getBase() { return base; } public void setBase(ValueNode base) { updateUsages(this.base, base); this.base = base; assert base != null && (base.stamp(NodeView.DEFAULT) instanceof AbstractPointerStamp || IntegerStamp.getBits(base.stamp(NodeView.DEFAULT)) == 64); } public ValueNode getOffset() { return offset; } public void setOffset(ValueNode offset) { updateUsages(this.offset, offset); this.offset = offset; assert offset != null && IntegerStamp.getBits(offset.stamp(NodeView.DEFAULT)) == 64; } @Override public Node canonical(CanonicalizerTool tool) { if (base instanceof OffsetAddressNode) { NodeView view = NodeView.from(tool); // Rewrite (&base[offset1])[offset2] to base[offset1 + offset2]. OffsetAddressNode b = (OffsetAddressNode) base; return new OffsetAddressNode(b.getBase(), BinaryArithmeticNode.add(b.getOffset(), this.getOffset(), view)); } else if (base instanceof AddNode) { AddNode add = (AddNode) base; if (add.getY().isConstant()) { return new OffsetAddressNode(add.getX(), new AddNode(add.getY(), getOffset())); } } return this; } @NodeIntrinsic public static native Address address(Object base, long offset); @Override public long getMaxConstantDisplacement() { Stamp curStamp = offset.stamp(NodeView.DEFAULT); if (curStamp instanceof IntegerStamp) { IntegerStamp integerStamp = (IntegerStamp) curStamp; if (integerStamp.lowerBound() >= 0) { return integerStamp.upperBound(); } } return Long.MAX_VALUE; } @Override public ValueNode getIndex() { return null; } }