Fix a bug in smi loop analysis....

src/data-flow.cc

 // 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
@@ skipping 1040 matching lines @@
   // The loop must have all necessary parts.
   if (stmt->init() == NULL || stmt->cond() == NULL || stmt->next() == NULL) {
     return NULL;
   }
   // The initialization statement has to be a simple assignment.
   Assignment* init = stmt->init()->StatementAsSimpleAssignment();
   if (init == NULL) return NULL;
 
   // We only deal with local variables.
   Variable* loop_var = init->target()->AsVariableProxy()->AsVariable();
-  if (!loop_var->IsStackAllocated()) return NULL;
+  if (loop_var == NULL || !loop_var->IsStackAllocated()) return NULL;
 
   // The initial value has to be a smi.
   Literal* init_lit = init->value()->AsLiteral();
   if (init_lit == NULL || !init_lit->handle()->IsSmi()) return NULL;
   int init_value = Smi::cast(*init_lit->handle())->value();
 
   // The condition must be a compare of variable with <, <=, >, or >=.
   CompareOperation* cond = stmt->cond()->AsCompareOperation();
   if (cond == NULL) return NULL;
   if (cond->op() != Token::LT
@@ skipping 759 matching lines @@
   for (int i = postorder->length() - 1; i >= 0; i--) {
     postorder->at(i)->PrintText();
   }
 }
 
 
 #endif  // defined(DEBUG)
 
 
 } }  // namespace v8::internal