Optimize calls to object literal properties that are initialized with a funct...

src/hydrogen.cc

Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc	(revision 7281)
+++ src/hydrogen.cc	(working copy)
@@ -2904,7 +2904,8 @@
                                                 expr->constant_properties(),
                                                 expr->fast_elements(),
                                                 expr->literal_index(),
-                                                expr->depth()));
+                                                expr->depth(),
+                                                expr->has_function()));
   // The object is expected in the bailout environment during computation
   // of the property values and is the value of the entire expression.
   PushAndAdd(literal);
@@ -2945,7 +2946,19 @@
       default: UNREACHABLE();
     }
   }
-  ast_context()->ReturnValue(Pop());
+
+  if (expr->has_function()) {
+    // Return the result of the transformation to fast properties
+    // instead of the original since this operation changes the map
+    // of the object. This makes sure that the original object won't
+    // be used by other optimized code before it is transformed
+    // (e.g. because of code motion).
+    HToFastProperties* result = new HToFastProperties(Pop());
+    AddInstruction(result);
+    ast_context()->ReturnValue(result);
+  } else {
+    ast_context()->ReturnValue(Pop());
+  }
 }