Check the depth of the constructed HEnvironment.

src/hydrogen.h

 // Copyright 2011 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 430 matching lines @@
     ASSERT(index < length());
     values_[index] = value;
   }
 
   void PrintTo(StringStream* stream);
   void PrintToStd();
 
  private:
   explicit HEnvironment(const HEnvironment* other);
 
+  void CheckDepth() {
+    // Verify that we are not trying to create an
+    // impossibly deeply nested environment.
+    if (!FLAG_limit_inlining) return;
+
+    static const int kMaxDepth = 4;
+
+    int cnt = 0;
+    for (HEnvironment* env = this;
+         env != NULL && cnt <= kMaxDepth;  // Check cnt to avoid infinite loop.
+         env = env->outer()) {
+      cnt++;
+    }
+
+    CHECK(cnt <= kMaxDepth);
+  }
+
   // True if index is included in the expression stack part of the environment.
   bool HasExpressionAt(int index) const;
 
   void Initialize(int parameter_count, int local_count, int stack_height);
   void Initialize(const HEnvironment* other);
 
   // Map a variable to an environment index.  Parameter indices are shifted
   // by 1 (receiver is parameter index -1 but environment index 0).
   // Stack-allocated local indices are shifted by the number of parameters.
   int IndexFor(Variable* variable) const {
@@ skipping 780 matching lines @@
   const char* filename_;
   HeapStringAllocator string_allocator_;
   StringStream trace_;
   int indent_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_