Deoptimizer support for hydrogen stubs that accept a variable number of arguments.

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 151a51ca31d03c123035dfc7a3c789b4a358eae9..e6a987e78e5c295ee286a6a3dcccbac7bd0c3542 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -263,11 +263,11 @@ struct CodeStubInterfaceDescriptor {
   CodeStubInterfaceDescriptor()
       : register_param_count_(-1),
         stack_parameter_count_(NULL),
-        extra_expression_stack_count_(0),
+        acting_as_js_function_(false),
         register_params_(NULL) { }
   int register_param_count_;
   const Register* stack_parameter_count_;
-  int extra_expression_stack_count_;
+  bool acting_as_js_function_;
   Register* register_params_;
   Address deoptimization_handler_;
 
@@ -1570,10 +1570,8 @@ class StoreArrayLiteralElementStub : public PlatformCodeStub {
 
 class StubFailureTrampolineStub : public PlatformCodeStub {
  public:
-  static const int kMaxExtraExpressionStackCount = 1;
-
-  explicit StubFailureTrampolineStub(int extra_expression_stack_count)
-      : extra_expression_stack_count_(extra_expression_stack_count) {}
+  explicit StubFailureTrampolineStub(bool acting_as_js_function)
+      : acting_as_js_function_(acting_as_js_function) {}
 
   virtual bool IsPregenerated() { return true; }
 
@@ -1581,11 +1579,11 @@ class StubFailureTrampolineStub : public PlatformCodeStub {
 
  private:
   Major MajorKey() { return StubFailureTrampoline; }
-  int MinorKey() { return extra_expression_stack_count_; }
+  int MinorKey() { return acting_as_js_function_; }
 
   void Generate(MacroAssembler* masm);
 
-  int extra_expression_stack_count_;
+  bool acting_as_js_function_;
 
   DISALLOW_COPY_AND_ASSIGN(StubFailureTrampolineStub);
 };