--- old/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/ir/VarNode.java 2020-04-15 18:48:11.000000000 +0530 +++ /dev/null 2020-04-15 18:48:12.000000000 +0530 @@ -1,293 +0,0 @@ -/* - * Copyright (c) 2010, 2013, 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. Oracle designates this - * particular file as subject to the "Classpath" exception as provided - * by Oracle in the LICENSE file that accompanied this code. - * - * 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 jdk.nashorn.internal.ir; - -import jdk.nashorn.internal.ir.annotations.Immutable; -import jdk.nashorn.internal.ir.visitor.NodeVisitor; - -/** - * Node represents a var/let declaration. - */ -@Immutable -public final class VarNode extends Statement implements Assignment { - private static final long serialVersionUID = 1L; - - /** Var name. */ - private final IdentNode name; - - /** Initialization expression. */ - private final Expression init; - - /** Is this a var statement (as opposed to a "var" in a for loop statement) */ - private final int flags; - - /** - * source order id to be used for this node. If this is -1, then we - * the default which is start position of this node. See also the - * method Node::getSourceOrder. - */ - private final int sourceOrder; - - /** Flag for ES6 LET declaration */ - public static final int IS_LET = 1 << 0; - - /** Flag for ES6 CONST declaration */ - public static final int IS_CONST = 1 << 1; - - /** Flag that determines if this is the last function declaration in a function - * This is used to micro optimize the placement of return value assignments for - * a program node */ - public static final int IS_LAST_FUNCTION_DECLARATION = 1 << 2; - - /** - * Constructor - * - * @param lineNumber line number - * @param token token - * @param finish finish - * @param name name of variable - * @param init init node or null if just a declaration - */ - public VarNode(final int lineNumber, final long token, final int finish, final IdentNode name, final Expression init) { - this(lineNumber, token, finish, name, init, 0); - } - - private VarNode(final VarNode varNode, final IdentNode name, final Expression init, final int flags) { - super(varNode); - this.sourceOrder = -1; - this.name = init == null ? name : name.setIsInitializedHere(); - this.init = init; - this.flags = flags; - } - - /** - * Constructor - * - * @param lineNumber line number - * @param token token - * @param finish finish - * @param name name of variable - * @param init init node or null if just a declaration - * @param flags flags - */ - public VarNode(final int lineNumber, final long token, final int finish, final IdentNode name, final Expression init, final int flags) { - this(lineNumber, token, -1, finish, name, init, flags); - } - - /** - * Constructor - * - * @param lineNumber line number - * @param token token - * @param sourceOrder source order - * @param finish finish - * @param name name of variable - * @param init init node or null if just a declaration - * @param flags flags - */ - public VarNode(final int lineNumber, final long token, final int sourceOrder, final int finish, final IdentNode name, final Expression init, final int flags) { - super(lineNumber, token, finish); - this.sourceOrder = sourceOrder; - this.name = init == null ? name : name.setIsInitializedHere(); - this.init = init; - this.flags = flags; - } - - @Override - public int getSourceOrder() { - return sourceOrder == -1? super.getSourceOrder() : sourceOrder; - } - - @Override - public boolean isAssignment() { - return hasInit(); - } - - @Override - public IdentNode getAssignmentDest() { - return isAssignment() ? name : null; - } - - @Override - public VarNode setAssignmentDest(final IdentNode n) { - return setName(n); - } - - @Override - public Expression getAssignmentSource() { - return isAssignment() ? getInit() : null; - } - - /** - * Is this a VAR node block scoped? This returns true for ECMAScript 6 LET and CONST nodes. - * @return true if an ES6 LET or CONST node - */ - public boolean isBlockScoped() { - return getFlag(IS_LET) || getFlag(IS_CONST); - } - - /** - * Is this an ECMAScript 6 LET node? - * @return true if LET node - */ - public boolean isLet() { - return getFlag(IS_LET); - } - - /** - * Is this an ECMAScript 6 CONST node? - * @return true if CONST node - */ - public boolean isConst() { - return getFlag(IS_CONST); - } - - /** - * Return the flags to use for symbols for this declaration. - * @return the symbol flags - */ - public int getSymbolFlags() { - if (isLet()) { - return Symbol.IS_VAR | Symbol.IS_LET; - } else if (isConst()) { - return Symbol.IS_VAR | Symbol.IS_CONST; - } - return Symbol.IS_VAR; - } - - /** - * Does this variable declaration have an init value - * @return true if an init exists, false otherwise - */ - public boolean hasInit() { - return init != null; - } - - /** - * Assist in IR navigation. - * @param visitor IR navigating visitor. - */ - @Override - public Node accept(final NodeVisitor visitor) { - if (visitor.enterVarNode(this)) { - // var is right associative, so visit init before name - final Expression newInit = init == null ? null : (Expression)init.accept(visitor); - final IdentNode newName = (IdentNode)name.accept(visitor); - final VarNode newThis; - if (name != newName || init != newInit) { - newThis = new VarNode(this, newName, newInit, flags); - } else { - newThis = this; - } - return visitor.leaveVarNode(newThis); - } - return this; - } - - @Override - public void toString(final StringBuilder sb, final boolean printType) { - sb.append(tokenType().getName()).append(' '); - name.toString(sb, printType); - - if (init != null) { - sb.append(" = "); - init.toString(sb, printType); - } - } - - /** - * If this is an assignment of the form {@code var x = init;}, get the init part. - * @return the expression to initialize the variable to, null if just a declaration - */ - public Expression getInit() { - return init; - } - - /** - * Reset the initialization expression - * @param init new initialization expression - * @return a node equivalent to this one except for the requested change. - */ - public VarNode setInit(final Expression init) { - if (this.init == init) { - return this; - } - return new VarNode(this, name, init, flags); - } - - /** - * Get the identifier for the variable - * @return IdentNode representing the variable being set or declared - */ - public IdentNode getName() { - return name; - } - - /** - * Reset the identifier for this VarNode - * @param name new IdentNode representing the variable being set or declared - * @return a node equivalent to this one except for the requested change. - */ - public VarNode setName(final IdentNode name) { - if (this.name == name) { - return this; - } - return new VarNode(this, name, init, flags); - } - - private VarNode setFlags(final int flags) { - if (this.flags == flags) { - return this; - } - return new VarNode(this, name, init, flags); - } - - /** - * Check if a flag is set for this var node - * @param flag flag - * @return true if flag is set - */ - public boolean getFlag(final int flag) { - return (flags & flag) == flag; - } - - /** - * Set a flag for this var node - * @param flag flag - * @return new node if flags changed, same otherwise - */ - public VarNode setFlag(final int flag) { - return setFlags(flags | flag); - } - - /** - * Returns true if this is a function declaration. - * @return true if this is a function declaration. - */ - public boolean isFunctionDeclaration() { - return init instanceof FunctionNode && ((FunctionNode)init).isDeclared(); - } -}