Eagerly deoptimize on never-executed code-paths.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
===================================================================
--- src/hydrogen-instructions.h	(revision 8085)
+++ src/hydrogen-instructions.h	(working copy)
@@ -96,6 +96,7 @@
   V(Constant)                                  \
   V(Context)                                   \
   V(DeleteProperty)                            \
+  V(EagerDeoptimize)                           \

[danno, 2011/06/01 10:11:27]

My gut feeling is that  Eager vs. Lazy isn't the right distinction. I think I
would prefer this to be a "SoftDeoptimize" and the other one to be explicitly a
"HardDeoptimize". 

[fschneider, 2011/06/01 11:04:48]

Done.

   V(Deoptimize)                                \
   V(Div)                                       \
   V(EnterInlined)                              \
@@ -845,6 +846,16 @@
 };
 
 
+class HEagerDeoptimize: public HTemplateInstruction<0> {
+ public:
+  virtual Representation RequiredInputRepresentation(int index) const {
+    return Representation::None();
+  }
+
+  DECLARE_CONCRETE_INSTRUCTION(EagerDeoptimize)
+};
+
+
 class HDeoptimize: public HControlInstruction {
  public:
   explicit HDeoptimize(int environment_length)
@@ -857,6 +868,7 @@
 
   virtual int OperandCount() { return values_.length(); }
   virtual HValue* OperandAt(int index) { return values_[index]; }
+  virtual void PrintDataTo(StringStream* stream);
 
   void AddEnvironmentValue(HValue* value) {
     values_.Add(NULL);