First take on custom call generators.

src/stub-cache.h

Index: src/stub-cache.h
diff --git a/src/stub-cache.h b/src/stub-cache.h
index 278b05c678acd52a10bb4c9ff53d7ed958119330..64846c141c27d6a6bd08cca5d93b97a36cc88839 100644
--- a/src/stub-cache.h
+++ b/src/stub-cache.h
@@ -548,7 +548,7 @@ class KeyedStoreStubCompiler: public StubCompiler {
 
 class CallStubCompiler: public StubCompiler {
  public:
-  explicit CallStubCompiler(int argc, InLoopFlag in_loop)
+  CallStubCompiler(int argc, InLoopFlag in_loop)
       : arguments_(argc), in_loop_(in_loop) { }
 
   Object* CompileCallField(JSObject* object,
@@ -569,6 +569,12 @@ class CallStubCompiler: public StubCompiler {
                             JSFunction* function,
                             String* name);
 
+  Object* CompileArrayPushCall(Object* object,
+                               JSObject* holder,
+                               JSFunction* function,
+                               String* name,
+                               CheckType check);
+
  private:
   const ParameterCount arguments_;
   const InLoopFlag in_loop_;
@@ -590,6 +596,14 @@ class ConstructStubCompiler: public StubCompiler {
 };
 
 
+typedef Object* (*CustomCallGenerator)(CallStubCompiler* compiler,
+                                       Object* object,
+                                       JSObject* holder,
+                                       JSFunction* function,
+                                       String* name,
+                                       StubCompiler::CheckType check);
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_STUB_CACHE_H_