diff options
Diffstat (limited to 'trunk/infrastructure/rhino1_7R1/src/org/mozilla/javascript/optimizer/Optimizer.java')
| -rw-r--r-- | trunk/infrastructure/rhino1_7R1/src/org/mozilla/javascript/optimizer/Optimizer.java | 510 |
1 files changed, 510 insertions, 0 deletions
diff --git a/trunk/infrastructure/rhino1_7R1/src/org/mozilla/javascript/optimizer/Optimizer.java b/trunk/infrastructure/rhino1_7R1/src/org/mozilla/javascript/optimizer/Optimizer.java new file mode 100644 index 0000000..575c7e7 --- /dev/null +++ b/trunk/infrastructure/rhino1_7R1/src/org/mozilla/javascript/optimizer/Optimizer.java @@ -0,0 +1,510 @@ +/* ***** 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.*; + +class Optimizer +{ + + static final int NoType = 0; + static final int NumberType = 1; + static final int AnyType = 3; + + // It is assumed that (NumberType | AnyType) == AnyType + + void optimize(ScriptOrFnNode scriptOrFn) + { + // run on one function at a time for now + int functionCount = scriptOrFn.getFunctionCount(); + for (int i = 0; i != functionCount; ++i) { + OptFunctionNode f = OptFunctionNode.get(scriptOrFn, i); + optimizeFunction(f); + } + } + + private void optimizeFunction(OptFunctionNode theFunction) + { + if (theFunction.fnode.requiresActivation()) return; + + inDirectCallFunction = theFunction.isTargetOfDirectCall(); + this.theFunction = theFunction; + + ObjArray statementsArray = new ObjArray(); + buildStatementList_r(theFunction.fnode, statementsArray); + Node[] theStatementNodes = new Node[statementsArray.size()]; + statementsArray.toArray(theStatementNodes); + + Block.runFlowAnalyzes(theFunction, theStatementNodes); + + if (!theFunction.fnode.requiresActivation()) { + /* + * Now that we know which local vars are in fact always + * Numbers, we re-write the tree to take advantage of + * that. Any arithmetic or assignment op involving just + * Number typed vars is marked so that the codegen will + * generate non-object code. + */ + parameterUsedInNumberContext = false; + for (int i = 0; i < theStatementNodes.length; i++) { + rewriteForNumberVariables(theStatementNodes[i]); + } + theFunction.setParameterNumberContext(parameterUsedInNumberContext); + } + + } + + +/* + Each directCall parameter is passed as a pair of values - an object + and a double. The value passed depends on the type of value available at + the call site. If a double is available, the object in java/lang/Void.TYPE + is passed as the object value, and if an object value is available, then + 0.0 is passed as the double value. + + The receiving routine always tests the object value before proceeding. + If the parameter is being accessed in a 'Number Context' then the code + sequence is : + if ("parameter_objectValue" == java/lang/Void.TYPE) + ...fine..., use the parameter_doubleValue + else + toNumber(parameter_objectValue) + + and if the parameter is being referenced in an Object context, the code is + if ("parameter_objectValue" == java/lang/Void.TYPE) + new Double(parameter_doubleValue) + else + ...fine..., use the parameter_objectValue + + If the receiving code never uses the doubleValue, it is converted on + entry to a Double instead. +*/ + + +/* + We're referencing a node in a Number context (i.e. we'd prefer it + was a double value). If the node is a parameter in a directCall + function, mark it as being referenced in this context. +*/ + private void markDCPNumberContext(Node n) + { + if (inDirectCallFunction && n.getType() == Token.GETVAR) { + int varIndex = theFunction.getVarIndex(n); + if (theFunction.isParameter(varIndex)) { + parameterUsedInNumberContext = true; + } + } + } + + private boolean convertParameter(Node n) + { + if (inDirectCallFunction && n.getType() == Token.GETVAR) { + int varIndex = theFunction.getVarIndex(n); + if (theFunction.isParameter(varIndex)) { + n.removeProp(Node.ISNUMBER_PROP); + return true; + } + } + return false; + } + + private int rewriteForNumberVariables(Node n) + { + switch (n.getType()) { + case Token.EXPR_VOID : { + Node child = n.getFirstChild(); + int type = rewriteForNumberVariables(child); + if (type == NumberType) + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NoType; + } + case Token.NUMBER : + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + + case Token.GETVAR : + { + int varIndex = theFunction.getVarIndex(n); + if (inDirectCallFunction + && theFunction.isParameter(varIndex)) + { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + else if (theFunction.isNumberVar(varIndex)) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + return NoType; + } + + case Token.INC : + case Token.DEC : { + Node child = n.getFirstChild(); + // "child" will be GETVAR or GETPROP or GETELEM + if (child.getType() == Token.GETVAR) { + if (rewriteForNumberVariables(child) == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + markDCPNumberContext(child); + return NumberType; + } + return NoType; + } + else if (child.getType() == Token.GETELEM) { + return rewriteForNumberVariables(child); + } + return NoType; + } + case Token.SETVAR : { + Node lChild = n.getFirstChild(); + Node rChild = lChild.getNext(); + int rType = rewriteForNumberVariables(rChild); + int varIndex = theFunction.getVarIndex(n); + if (inDirectCallFunction + && theFunction.isParameter(varIndex)) + { + if (rType == NumberType) { + if (!convertParameter(rChild)) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + markDCPNumberContext(rChild); + return NoType; + } + else + return rType; + } + else if (theFunction.isNumberVar(varIndex)) { + if (rType != NumberType) { + n.removeChild(rChild); + n.addChildToBack( + new Node(Token.TO_DOUBLE, rChild)); + } + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + markDCPNumberContext(rChild); + return NumberType; + } + else { + if (rType == NumberType) { + if (!convertParameter(rChild)) { + n.removeChild(rChild); + n.addChildToBack( + new Node(Token.TO_OBJECT, rChild)); + } + } + return NoType; + } + } + case Token.LE : + case Token.LT : + case Token.GE : + case Token.GT : { + Node lChild = n.getFirstChild(); + Node rChild = lChild.getNext(); + int lType = rewriteForNumberVariables(lChild); + int rType = rewriteForNumberVariables(rChild); + markDCPNumberContext(lChild); + markDCPNumberContext(rChild); + + if (convertParameter(lChild)) { + if (convertParameter(rChild)) { + return NoType; + } else if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.RIGHT); + } + } + else if (convertParameter(rChild)) { + if (lType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.LEFT); + } + } + else { + if (lType == NumberType) { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + } + else { + n.putIntProp(Node.ISNUMBER_PROP, Node.LEFT); + } + } + else { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.RIGHT); + } + } + } + // we actually build a boolean value + return NoType; + } + + case Token.ADD : { + Node lChild = n.getFirstChild(); + Node rChild = lChild.getNext(); + int lType = rewriteForNumberVariables(lChild); + int rType = rewriteForNumberVariables(rChild); + + + if (convertParameter(lChild)) { + if (convertParameter(rChild)) { + return NoType; + } + else { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.RIGHT); + } + } + } + else { + if (convertParameter(rChild)) { + if (lType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.LEFT); + } + } + else { + if (lType == NumberType) { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + else { + n.putIntProp(Node.ISNUMBER_PROP, Node.LEFT); + } + } + else { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, + Node.RIGHT); + } + } + } + } + return NoType; + } + + case Token.BITXOR : + case Token.BITOR : + case Token.BITAND : + case Token.RSH : + case Token.LSH : + case Token.SUB : + case Token.MUL : + case Token.DIV : + case Token.MOD : { + Node lChild = n.getFirstChild(); + Node rChild = lChild.getNext(); + int lType = rewriteForNumberVariables(lChild); + int rType = rewriteForNumberVariables(rChild); + markDCPNumberContext(lChild); + markDCPNumberContext(rChild); + if (lType == NumberType) { + if (rType == NumberType) { + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + else { + if (!convertParameter(rChild)) { + n.removeChild(rChild); + n.addChildToBack( + new Node(Token.TO_DOUBLE, rChild)); + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + } + return NumberType; + } + } + else { + if (rType == NumberType) { + if (!convertParameter(lChild)) { + n.removeChild(lChild); + n.addChildToFront( + new Node(Token.TO_DOUBLE, lChild)); + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + } + return NumberType; + } + else { + if (!convertParameter(lChild)) { + n.removeChild(lChild); + n.addChildToFront( + new Node(Token.TO_DOUBLE, lChild)); + } + if (!convertParameter(rChild)) { + n.removeChild(rChild); + n.addChildToBack( + new Node(Token.TO_DOUBLE, rChild)); + } + n.putIntProp(Node.ISNUMBER_PROP, Node.BOTH); + return NumberType; + } + } + } + case Token.SETELEM : + case Token.SETELEM_OP : { + Node arrayBase = n.getFirstChild(); + Node arrayIndex = arrayBase.getNext(); + Node rValue = arrayIndex.getNext(); + int baseType = rewriteForNumberVariables(arrayBase); + if (baseType == NumberType) {// can never happen ??? + if (!convertParameter(arrayBase)) { + n.removeChild(arrayBase); + n.addChildToFront( + new Node(Token.TO_OBJECT, arrayBase)); + } + } + int indexType = rewriteForNumberVariables(arrayIndex); + if (indexType == NumberType) { + // setting the ISNUMBER_PROP signals the codegen + // to use the OptRuntime.setObjectIndex that takes + // a double index + n.putIntProp(Node.ISNUMBER_PROP, Node.LEFT); + markDCPNumberContext(arrayIndex); + } + int rValueType = rewriteForNumberVariables(rValue); + if (rValueType == NumberType) { + if (!convertParameter(rValue)) { + n.removeChild(rValue); + n.addChildToBack( + new Node(Token.TO_OBJECT, rValue)); + } + } + return NoType; + } + case Token.GETELEM : { + Node arrayBase = n.getFirstChild(); + Node arrayIndex = arrayBase.getNext(); + int baseType = rewriteForNumberVariables(arrayBase); + if (baseType == NumberType) {// can never happen ??? + if (!convertParameter(arrayBase)) { + n.removeChild(arrayBase); + n.addChildToFront( + new Node(Token.TO_OBJECT, arrayBase)); + } + } + int indexType = rewriteForNumberVariables(arrayIndex); + if (indexType == NumberType) { + if (!convertParameter(arrayIndex)) { + // setting the ISNUMBER_PROP signals the codegen + // to use the OptRuntime.getObjectIndex that takes + // a double index + n.putIntProp(Node.ISNUMBER_PROP, Node.RIGHT); + } + } + return NoType; + } + case Token.CALL : + { + Node child = n.getFirstChild(); // the function node + if (child.getType() == Token.GETELEM) { + // Optimization of x[0]() is not supported + // so bypass GETELEM optimization that + // rewriteForNumberVariables would trigger + rewriteAsObjectChildren(child, child.getFirstChild()); + } else { + rewriteForNumberVariables(child); + } + child = child.getNext(); // the first arg + + OptFunctionNode target + = (OptFunctionNode)n.getProp(Node.DIRECTCALL_PROP); + if (target != null) { +/* + we leave each child as a Number if it can be. The codegen will + handle moving the pairs of parameters. +*/ + while (child != null) { + int type = rewriteForNumberVariables(child); + if (type == NumberType) { + markDCPNumberContext(child); + } + child = child.getNext(); + } + } else { + rewriteAsObjectChildren(n, child); + } + return NoType; + } + default : { + rewriteAsObjectChildren(n, n.getFirstChild()); + return NoType; + } + } + } + + private void rewriteAsObjectChildren(Node n, Node child) + { + // Force optimized children to be objects + while (child != null) { + Node nextChild = child.getNext(); + int type = rewriteForNumberVariables(child); + if (type == NumberType) { + if (!convertParameter(child)) { + n.removeChild(child); + Node nuChild = new Node(Token.TO_OBJECT, child); + if (nextChild == null) + n.addChildToBack(nuChild); + else + n.addChildBefore(nuChild, nextChild); + } + } + child = nextChild; + } + } + + private static void buildStatementList_r(Node node, ObjArray statements) + { + int type = node.getType(); + if (type == Token.BLOCK + || type == Token.LOCAL_BLOCK + || type == Token.LOOP + || type == Token.FUNCTION) + { + Node child = node.getFirstChild(); + while (child != null) { + buildStatementList_r(child, statements); + child = child.getNext(); + } + } else { + statements.add(node); + } + } + + private boolean inDirectCallFunction; + OptFunctionNode theFunction; + private boolean parameterUsedInNumberContext; +} |