Check for phi-uses of arguments object before eliminating dead phi's.

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 224 matching lines @@
   void EliminateRedundantPhis();
   void EliminateUnreachablePhis();
   void Canonicalize();
   void OrderBlocks();
   void AssignDominators();
   void ReplaceCheckedValues();
   void PropagateDeoptimizingMark();
 
   // Returns false if there are phi-uses of the arguments-object
   // which are not supported by the optimizing compiler.
+  bool CheckPhis();
+
+  // Returns false if there are phi-uses of hole values comming
+  // from uninitialized consts.
   bool CollectPhis();
 
   Handle<Code> Compile(CompilationInfo* info);
 
   void set_undefined_constant(HConstant* constant) {
     undefined_constant_.set(constant);
   }
   HConstant* GetConstantUndefined() const { return undefined_constant_.get(); }
   HConstant* GetConstant1();
   HConstant* GetConstantMinus1();
@@ skipping 967 matching lines @@
   const char* filename_;
   HeapStringAllocator string_allocator_;
   StringStream trace_;
   int indent_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_