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+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Rhino code, released
+ * May 6, 1999.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1997-1999
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Norris Boyd
+ * Roger Lawrence
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License Version 2 or later (the "GPL"), in which
+ * case the provisions of the GPL are applicable instead of those above. If
+ * you wish to allow use of your version of this file only under the terms of
+ * the GPL and not to allow others to use your version of this file under the
+ * MPL, indicate your decision by deleting the provisions above and replacing
+ * them with the notice and other provisions required by the GPL. If you do
+ * not delete the provisions above, a recipient may use your version of this
+ * file under either the MPL or the GPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+
+package org.mozilla.javascript.optimizer;
+
+import org.mozilla.javascript.*;
+import java.util.Hashtable;
+
+/**
+ * This class performs node transforms to prepare for optimization.
+ *
+ * @see NodeTransformer
+ * @author Norris Boyd
+ */
+
+class OptTransformer extends NodeTransformer {
+
+ OptTransformer(Hashtable possibleDirectCalls, ObjArray directCallTargets)
+ {
+ this.possibleDirectCalls = possibleDirectCalls;
+ this.directCallTargets = directCallTargets;
+ }
+
+ protected void visitNew(Node node, ScriptOrFnNode tree) {
+ detectDirectCall(node, tree);
+ super.visitNew(node, tree);
+ }
+
+ protected void visitCall(Node node, ScriptOrFnNode tree) {
+ detectDirectCall(node, tree);
+ super.visitCall(node, tree);
+ }
+
+ private void detectDirectCall(Node node, ScriptOrFnNode tree)
+ {
+ if (tree.getType() == Token.FUNCTION) {
+ Node left = node.getFirstChild();
+
+ // count the arguments
+ int argCount = 0;
+ Node arg = left.getNext();
+ while (arg != null) {
+ arg = arg.getNext();
+ argCount++;
+ }
+
+ if (argCount == 0) {
+ OptFunctionNode.get(tree).itsContainsCalls0 = true;
+ }
+
+ /*
+ * Optimize a call site by converting call("a", b, c) into :
+ *
+ * FunctionObjectFor"a" <-- instance variable init'd by constructor
+ *
+ * // this is a DIRECTCALL node
+ * fn = GetProp(tmp = GetBase("a"), "a");
+ * if (fn == FunctionObjectFor"a")
+ * fn.call(tmp, b, c)
+ * else
+ * ScriptRuntime.Call(fn, tmp, b, c)
+ */
+ if (possibleDirectCalls != null) {
+ String targetName = null;
+ if (left.getType() == Token.NAME) {
+ targetName = left.getString();
+ } else if (left.getType() == Token.GETPROP) {
+ targetName = left.getFirstChild().getNext().getString();
+ } else if (left.getType() == Token.GETPROPNOWARN) {
+ throw Kit.codeBug();
+ }
+ if (targetName != null) {
+ OptFunctionNode ofn;
+ ofn = (OptFunctionNode)possibleDirectCalls.get(targetName);
+ if (ofn != null
+ && argCount == ofn.fnode.getParamCount()
+ && !ofn.fnode.requiresActivation())
+ {
+ // Refuse to directCall any function with more
+ // than 32 parameters - prevent code explosion
+ // for wacky test cases
+ if (argCount <= 32) {
+ node.putProp(Node.DIRECTCALL_PROP, ofn);
+ if (!ofn.isTargetOfDirectCall()) {
+ int index = directCallTargets.size();
+ directCallTargets.add(ofn);
+ ofn.setDirectTargetIndex(index);
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+
+ private Hashtable possibleDirectCalls;
+ private ObjArray directCallTargets;
+}