Reduce size of LIR instruction by one word and remove dead code.

src/x64/lithium-x64.h

Index: src/x64/lithium-x64.h
===================================================================
--- src/x64/lithium-x64.h	(revision 11356)
+++ src/x64/lithium-x64.h	(working copy)
@@ -204,8 +204,7 @@
   LInstruction()
       :  environment_(NULL),
          hydrogen_value_(NULL),
-         is_call_(false),
-         is_save_doubles_(false) { }
+         is_call_(false) { }
 
   virtual ~LInstruction() { }
 
@@ -248,22 +247,12 @@
   void set_hydrogen_value(HValue* value) { hydrogen_value_ = value; }
   HValue* hydrogen_value() const { return hydrogen_value_; }
 
-  void set_deoptimization_environment(LEnvironment* env) {
-    deoptimization_environment_.set(env);
-  }
-  LEnvironment* deoptimization_environment() const {
-    return deoptimization_environment_.get();
-  }
-  bool HasDeoptimizationEnvironment() const {
-    return deoptimization_environment_.is_set();
-  }
-
   void MarkAsCall() { is_call_ = true; }
-  void MarkAsSaveDoubles() { is_save_doubles_ = true; }
 
+  virtual void SetDeferredLazyDeoptimizationEnvironment(LEnvironment* env) { }
+
   // Interface to the register allocator and iterators.
   bool IsMarkedAsCall() const { return is_call_; }
-  bool IsMarkedAsSaveDoubles() const { return is_save_doubles_; }
 
   virtual bool HasResult() const = 0;
   virtual LOperand* result() = 0;
@@ -284,9 +273,7 @@
   LEnvironment* environment_;
   SetOncePointer<LPointerMap> pointer_map_;
   HValue* hydrogen_value_;
-  SetOncePointer<LEnvironment> deoptimization_environment_;
   bool is_call_;
-  bool is_save_doubles_;
 };
 
 
@@ -831,6 +818,15 @@
   DECLARE_HYDROGEN_ACCESSOR(InstanceOfKnownGlobal)
 
   Handle<JSFunction> function() const { return hydrogen()->function(); }
+  LEnvironment* GetDeferredLazyDeoptimizationEnvironment() {
+    return lazy_deopt_env_;
+  }
+  virtual void SetDeferredLazyDeoptimizationEnvironment(LEnvironment* env) {
+    lazy_deopt_env_ = env;
+  }
+
+ private:
+  LEnvironment* lazy_deopt_env_;
 };
 
 
@@ -2350,12 +2346,7 @@
       LInstruction* instr,
       HInstruction* hinstr,
       CanDeoptimize can_deoptimize = CANNOT_DEOPTIMIZE_EAGERLY);
-  LInstruction* MarkAsSaveDoubles(LInstruction* instr);
 
-  LInstruction* SetInstructionPendingDeoptimizationEnvironment(
-      LInstruction* instr, int ast_id);
-  void ClearInstructionPendingDeoptimizationEnvironment();
-
   LEnvironment* CreateEnvironment(HEnvironment* hydrogen_env,
                                   int* argument_index_accumulator);