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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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 jdk.nashorn.internal.codegen;

import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.FIRST_PROGRAM_POINT;
import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.MAX_PROGRAM_POINT_VALUE;

import java.util.HashSet;
import java.util.Set;
import jdk.nashorn.internal.IntDeque;
import jdk.nashorn.internal.ir.AccessNode;
import jdk.nashorn.internal.ir.BinaryNode;
import jdk.nashorn.internal.ir.CallNode;
import jdk.nashorn.internal.ir.Expression;
import jdk.nashorn.internal.ir.FunctionNode;
import jdk.nashorn.internal.ir.IdentNode;
import jdk.nashorn.internal.ir.IndexNode;
import jdk.nashorn.internal.ir.Node;
import jdk.nashorn.internal.ir.Optimistic;
import jdk.nashorn.internal.ir.UnaryNode;
import jdk.nashorn.internal.ir.VarNode;
import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor;

Find program points in the code that are needed for optimistic assumptions
/** * Find program points in the code that are needed for optimistic assumptions */
class ProgramPoints extends SimpleNodeVisitor { private final IntDeque nextProgramPoint = new IntDeque(); private final Set<Node> noProgramPoint = new HashSet<>(); private int next() { final int next = nextProgramPoint.getAndIncrement(); if(next > MAX_PROGRAM_POINT_VALUE) { throw new AssertionError("Function has more than " + MAX_PROGRAM_POINT_VALUE + " program points"); } return next; } @Override public boolean enterFunctionNode(final FunctionNode functionNode) { nextProgramPoint.push(FIRST_PROGRAM_POINT); return true; } @Override public Node leaveFunctionNode(final FunctionNode functionNode) { nextProgramPoint.pop(); return functionNode; } private Expression setProgramPoint(final Optimistic optimistic) { if (noProgramPoint.contains(optimistic)) { return (Expression)optimistic; } return (Expression)(optimistic.canBeOptimistic() ? optimistic.setProgramPoint(next()) : optimistic); } @Override public boolean enterVarNode(final VarNode varNode) { noProgramPoint.add(varNode.getName()); return true; } @Override public boolean enterIdentNode(final IdentNode identNode) { if (identNode.isInternal()) { noProgramPoint.add(identNode); } return true; } @Override public Node leaveIdentNode(final IdentNode identNode) { if(identNode.isPropertyName()) { return identNode; } return setProgramPoint(identNode); } @Override public Node leaveCallNode(final CallNode callNode) { return setProgramPoint(callNode); } @Override public Node leaveAccessNode(final AccessNode accessNode) { return setProgramPoint(accessNode); } @Override public Node leaveIndexNode(final IndexNode indexNode) { return setProgramPoint(indexNode); } @Override public Node leaveBinaryNode(final BinaryNode binaryNode) { return setProgramPoint(binaryNode); } @Override public Node leaveUnaryNode(final UnaryNode unaryNode) { return setProgramPoint(unaryNode); } }