Fix bug with range of shift operations.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/bit_vector.h"
 #include "vm/cpu.h"
 #include "vm/dart_entry.h"
@@ skipping 1215 matching lines @@
     return true;
   }
   switch (op_kind()) {
     case Token::kBIT_AND:
     case Token::kBIT_OR:
     case Token::kBIT_XOR:
       return false;
     case Token::kSHR: {
       // Can't deopt if shift-count is known positive.
       Range* right_range = this->right()->definition()->range();
-      return (right_range == NULL) || right_range->IsNegative();
+      return (right_range == NULL) || !right_range->IsPositive();
     }
     case Token::kSHL: {
       Range* right_range = this->right()->definition()->range();
       if ((right_range != NULL) && is_truncating()) {
         // Can deoptimize if right can be negative.
-        return right_range->IsNegative();
+        return !right_range->IsPositive();
       }
       return true;
     }
     case Token::kMOD: {
       Range* right_range = this->right()->definition()->range();
       return (right_range == NULL) || right_range->Overlaps(0, 0);
     }
     default:
       return overflow_;
   }
@@ skipping 2307 matching lines @@
     case Token::kTRUNCDIV: return 0;
     case Token::kMOD: return 1;
     default: UNIMPLEMENTED(); return -1;
   }
 }
 
 
 #undef __
 
 }  // namespace dart