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 e91b241579b0389aee2f373b262e80c0aefd7102..50705b6650bcafd8c30732fcc0a992f0e822929d 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -259,15 +259,17 @@ class PlatformCodeStub : public CodeStub {
 };
 
 
+enum StubFunctionMode { NOT_JS_FUNCTION_MODE, JS_FUNCTION_MODE };

[danno, 2013/04/02 10:39:44]

How about NOT_JS_FUNCTION_STUB_MODE and JS_FUNCTION_STUB_MODE? Makes it a bit
clear and less ambiguous in the global namespace.

[mvstanton, 2013/04/02 11:27:25]

Done.

+
 struct CodeStubInterfaceDescriptor {
   CodeStubInterfaceDescriptor()
       : register_param_count_(-1),
         stack_parameter_count_(NULL),
-        extra_expression_stack_count_(0),
+        function_mode_(NOT_JS_FUNCTION_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_;
 
@@ -1570,10 +1572,8 @@ 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(StubFunctionMode function_mode)
+      : function_mode_(function_mode) {}
 
   virtual bool IsPregenerated() { return true; }
 
@@ -1581,11 +1581,11 @@ class StubFailureTrampolineStub : public PlatformCodeStub {
 
  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);
 };