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

src/code-stubs.h

 // Copyright 2012 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 240 matching lines @@
 
   virtual int GetCodeKind() { return Code::STUB; }
   virtual int GetStubFlags() { return -1; }
 
  protected:
   // Generates the assembler code for the stub.
   virtual void Generate(MacroAssembler* masm) = 0;
 };
 
 
+enum StubFunctionMode { NOT_JS_FUNCTION_STUB_MODE, JS_FUNCTION_STUB_MODE };
+
 struct CodeStubInterfaceDescriptor {
   CodeStubInterfaceDescriptor()
       : register_param_count_(-1),
         stack_parameter_count_(NULL),
-        extra_expression_stack_count_(0),
+        function_mode_(NOT_JS_FUNCTION_STUB_MODE),
         register_params_(NULL) { }
   int register_param_count_;
   const Register* stack_parameter_count_;
-  int extra_expression_stack_count_;
+  StubFunctionMode function_mode_;
   Register* register_params_;
   Address deoptimization_handler_;
 
   int environment_length() const {
     if (stack_parameter_count_ != NULL) {
       return register_param_count_ + 1;
     }
     return register_param_count_;
   }
 };
@@ skipping 1314 matching lines @@
   void Generate(MacroAssembler* masm);
 
   bool fp_registers_;
 
   DISALLOW_COPY_AND_ASSIGN(StoreArrayLiteralElementStub);
 };
 
 
 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(StubFunctionMode function_mode)
+      : function_mode_(function_mode) {}
 
   virtual bool IsPregenerated() { return true; }
 
   static void GenerateAheadOfTime(Isolate* isolate);
 
  private:
   Major MajorKey() { return StubFailureTrampoline; }
-  int MinorKey() { return extra_expression_stack_count_; }
+  int MinorKey() { return static_cast<int>(function_mode_); }
 
   void Generate(MacroAssembler* masm);
 
-  int extra_expression_stack_count_;
+  StubFunctionMode function_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(StubFailureTrampolineStub);
 };
 
 
 class ProfileEntryHookStub : public PlatformCodeStub {
  public:
   explicit ProfileEntryHookStub() {}
 
   // The profile entry hook function is not allowed to cause a GC.
@@ skipping 20 matching lines @@
 
   // The current function entry hook.
   static FunctionEntryHook entry_hook_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileEntryHookStub);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_