Define DEBUG for v8_optimized_debug=2

src/utils.h

 // Copyright 2012 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 401 matching lines @@
     ASSERT(length == 0 || (length > 0 && data != NULL));
   }
 
   static Vector<T> New(int length) {
     return Vector<T>(NewArray<T>(length), length);
   }
 
   // Returns a vector using the same backing storage as this one,
   // spanning from and including 'from', to but not including 'to'.
   Vector<T> SubVector(int from, int to) {
-    ASSERT(to <= length_);
-    ASSERT(from < to);
+    SLOW_ASSERT(to <= length_);
+    SLOW_ASSERT(from < to);
     ASSERT(0 <= from);
     return Vector<T>(start() + from, to - from);
   }
 
   // Returns the length of the vector.
   int length() const { return length_; }
 
   // Returns whether or not the vector is empty.
   bool is_empty() const { return length_ == 0; }
 
@@ skipping 701 matching lines @@
 
   // Every compiled stub starts with this id.
   static const int kStubEntryId = 5;
 
   int id_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_UTILS_H_