Reviewers: Kevin Millikin,

Description:
Fix bug in assigned variables analysis.

Property stores were not visited correctly by the visitor.
I fixed this issue by visiting property stores by visiting
receiver and key directly (and not calling visit on the lhs property
 ast node)


Please review this at http://codereview.chromium.org/903003

SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/

Affected files:
  M     src/data-flow.cc
  A     test/mjsunit/regress/regress-643.js


Index: test/mjsunit/regress/regress-643.js
===================================================================
--- test/mjsunit/regress/regress-643.js (revision 0)
+++ test/mjsunit/regress/regress-643.js (revision 0)
@@ -0,0 +1,37 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Regression test for http://code.google.com/p/v8/issues/detail?id=643.
+
+function f() {
+  var test = {x:1};
+  var a = test;
+  a.x = a = 42;
+  return test.x;
+}
+
+assertEquals(42, f());
Index: src/data-flow.cc
===================================================================
--- src/data-flow.cc    (revision 4112)
+++ src/data-flow.cc    (working copy)
@@ -1360,21 +1360,30 @@
 void AssignedVariablesAnalyzer::VisitAssignment(Assignment* expr) {
   ASSERT(av_.IsEmpty());

-  Visit(expr->target());
+  if (expr->target()->AsProperty() != NULL) {
+    // Visit receiver and key of property store.
+    Visit(expr->target()->AsProperty()->obj());

-  ProcessExpression(expr->value());
+    ProcessExpression(expr->target()->AsProperty()->key());

-  Variable* var = expr->target()->AsVariableProxy()->AsVariable();
-  if (var != NULL) RecordAssignedVar(var);
+    ProcessExpression(expr->value());

-  // If we have a variable as a receiver in a property store, check if
-  // we can mark it as trivial.
-  if (expr->target()->AsProperty() != NULL) {
+    // If we have a variable as a receiver in a property store, check if
+    // we can mark it as trivial.
     MarkIfTrivial(expr->target()->AsProperty()->obj());
+  } else {
+
+    Visit(expr->target());
+
+    ProcessExpression(expr->value());
+
+    Variable* var = expr->target()->AsVariableProxy()->AsVariable();
+    if (var != NULL) RecordAssignedVar(var);
   }
 }


+
 void AssignedVariablesAnalyzer::VisitThrow(Throw* expr) {
   ASSERT(av_.IsEmpty());
   Visit(expr->exception());


--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev

Reply via email to