From 174a30454c7ad08c21d63ab5c43f23a129609d98 Mon Sep 17 00:00:00 2001
From: msridhar1 <msridhar1@f5eafffb-2e1d-0410-98e4-8ec43c5233c4>
Date: Wed, 8 Feb 2012 15:32:15 +0000
Subject: [PATCH] Started to update the closure extractor to work with Rhino
 1.7.3.

git-svn-id: https://wala.svn.sourceforge.net/svnroot/wala/trunk@4438 f5eafffb-2e1d-0410-98e4-8ec43c5233c4
---
 .../extraction/ClosureExtractor.java          | 24 ++++++++------
 .../extraction/ForInBodyExtractionPolicy.java | 32 ++++++++++++++++---
 2 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ClosureExtractor.java b/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ClosureExtractor.java
index 341b66e5e..49baf5c28 100644
--- a/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ClosureExtractor.java
+++ b/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ClosureExtractor.java
@@ -172,6 +172,8 @@ import com.ibm.wala.util.debug.UnimplementedError;
  *
  */
 public class ClosureExtractor extends CAstRewriterExt {
+  private static final boolean RHINO_1_7_2 = false;
+  
   private LinkedList<ExtractionPolicy> policies = new LinkedList<ExtractionPolicy>();
   private final ExtractionPolicyFactory policyFactory;
   
@@ -388,6 +390,8 @@ public class ClosureExtractor extends CAstRewriterExt {
   }
 
   private int anonymous_counter = 0;
+  
+  @SuppressWarnings("unused")
   private List<CAstNode> extractRegion(CAstNode root, CAstControlFlowMap cfg, ExtractionPos context, Map<Pair<CAstNode, NoKey>, CAstNode> nodeMap) {
     CAstEntity entity = getCurrentEntity();
 
@@ -412,26 +416,28 @@ public class ClosureExtractor extends CAstRewriterExt {
      */
     ArrayList<CAstNode> prologue = new ArrayList<CAstNode>();
     ArrayList<CAstNode> fun_body_stmts = new ArrayList<CAstNode>();
-    CAstNode self_ref = makeVarRef(name);
-    CAstNode self_assign = Ast.makeNode(ASSIGN, self_ref, makeVarRef(name));
-    addFlow(self_ref, JavaScriptTypes.ReferenceError, CAstControlFlowMap.EXCEPTION_TO_EXIT, entity.getControlFlow());
-    fun_body_stmts.add(self_assign);
+    if(RHINO_1_7_2) {
+      CAstNode self_ref = makeVarRef(name);
+      CAstNode self_assign = Ast.makeNode(ASSIGN, self_ref, makeVarRef(name));
+      addFlow(self_ref, JavaScriptTypes.ReferenceError, CAstControlFlowMap.EXCEPTION_TO_EXIT, entity.getControlFlow());
+      fun_body_stmts.add(self_assign);
+    }
 
     // if we are extracting a block, unwrap it
     if(extractingBlock) {
       CAstNode block = root.getChild(context.getStart());
       for(int i=0;i<block.getChildCount();++i)
         fun_body_stmts.add(block.getChild(i));
-      if(mayCompleteNormally(block))
+      if(RHINO_1_7_2 && mayCompleteNormally(block))
         fun_body_stmts.add(markSynthetic(Ast.makeNode(RETURN)));
     } else {
       if(context.getRegion() instanceof TwoLevelExtractionRegion) {
         CAstNode start = root.getChild(context.getStart());
         TwoLevelExtractionRegion tler = (TwoLevelExtractionRegion)context.getRegion();
-        if(start.getKind() != CAstNode.BLOCK_EXPR)
-          throw new IllegalArgumentException("Invalid two-level extraction region.");
         if(tler.getEndInner() != -1)
           throw new UnimplementedError("Two-level extraction not fully implemented.");
+        if(start.getKind() != CAstNode.BLOCK_EXPR)
+          throw new IllegalArgumentException("Invalid two-level extraction region.");
         int i;
         for(i=0;i<tler.getStartInner();++i)
           prologue.add(copyNodes(start.getChild(i), cfg, context, nodeMap));
@@ -449,11 +455,11 @@ public class ClosureExtractor extends CAstRewriterExt {
           fun_body_stmts.add(root.getChild(context.getStart()));
         }
       }
-      if(mayCompleteNormally(root.getChild(context.getEnd()-1)))
+      if(RHINO_1_7_2 && mayCompleteNormally(root.getChild(context.getEnd()-1)))
         fun_body_stmts.add(markSynthetic(Ast.makeNode(RETURN)));
     }
     CAstNode inner_block = Ast.makeNode(BLOCK_STMT, fun_body_stmts.toArray(new CAstNode[0]));
-    CAstNode fun_body = Ast.makeNode(BLOCK_STMT, inner_block);
+    CAstNode fun_body = RHINO_1_7_2 ? Ast.makeNode(BLOCK_STMT, inner_block) : inner_block;
 
     /*
      * Now we rewrite the body and construct a Rewrite object.
diff --git a/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ForInBodyExtractionPolicy.java b/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ForInBodyExtractionPolicy.java
index 35c91ebc1..66a439086 100644
--- a/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ForInBodyExtractionPolicy.java
+++ b/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/extraction/ForInBodyExtractionPolicy.java
@@ -13,7 +13,9 @@ package com.ibm.wala.cast.js.ipa.callgraph.correlations.extraction;
 
 import static com.ibm.wala.cast.tree.CAstNode.ASSIGN;
 import static com.ibm.wala.cast.tree.CAstNode.BLOCK_STMT;
+import static com.ibm.wala.cast.tree.CAstNode.DECL_STMT;
 import static com.ibm.wala.cast.tree.CAstNode.EACH_ELEMENT_GET;
+import static com.ibm.wala.cast.tree.CAstNode.LABEL_STMT;
 import static com.ibm.wala.cast.tree.CAstNode.VAR;
 
 import java.util.Collections;
@@ -21,7 +23,11 @@ import java.util.List;
 
 import com.ibm.wala.cast.tree.CAstEntity;
 import com.ibm.wala.cast.tree.CAstNode;
-import com.ibm.wala.cast.tree.pattern.*;
+import com.ibm.wala.cast.tree.pattern.Alt;
+import com.ibm.wala.cast.tree.pattern.AnyNode;
+import com.ibm.wala.cast.tree.pattern.NodeOfKind;
+import com.ibm.wala.cast.tree.pattern.SomeConstant;
+import com.ibm.wala.cast.tree.pattern.SubtreeOfKind;
 
 /**
  * A policy telling a {@link ClosureExtractor} to extract the body of every for-in loop.
@@ -47,7 +53,27 @@ public class ForInBodyExtractionPolicy extends ExtractionPolicy {
   @Override
   public List<ExtractionRegion> extract(CAstNode node) {
     SomeConstant loopVar = new SomeConstant();
-    /* matches the following pattern:
+    
+    /* 
+     * matches Rhino 1.7.3 encoding of for-in loop bodies:
+     * 
+     *   BLOCK_STMT
+     *     decl/assign of loop variable
+     *     <loopBody>
+     */
+    if(new NodeOfKind(BLOCK_STMT,
+        new Alt(new NodeOfKind(DECL_STMT,
+                               loopVar,
+                               new SubtreeOfKind(EACH_ELEMENT_GET)),
+                new NodeOfKind(ASSIGN,
+                               new NodeOfKind(VAR, loopVar),
+                               new SubtreeOfKind(EACH_ELEMENT_GET))),
+        new AnyNode(),
+        new SubtreeOfKind(LABEL_STMT)).matches(node)) {
+      return Collections.singletonList(new ExtractionRegion(1, 2, Collections.singletonList((String)loopVar.getLastMatch())));
+    }
+    
+    /* matches Rhino < 1.7.3 encoding of for-in loop bodies:
      * 
      *   BLOCK_STMT
      *     ASSIGN
@@ -55,8 +81,6 @@ public class ForInBodyExtractionPolicy extends ExtractionPolicy {
      *       EACH_ELEMENT_GET
      *         VAR <forin_tmp>
      *     <loopBody>
-     *     
-     * TODO: this is too brittle; what if future versions of Rhino encode for-in loops differently?
      */
     if(new NodeOfKind(BLOCK_STMT,
         new NodeOfKind(ASSIGN,