[turbofan] Add NewUnmappedArgumentsElements and NewRestParametersArguments.

src/compiler/simplified-operator.h

Index: src/compiler/simplified-operator.h
diff --git a/src/compiler/simplified-operator.h b/src/compiler/simplified-operator.h
index 833a0554f588b11dc3af3f85c16223fa61c32d1e..4c331136ca408ac9d2a6cf3e38c1a82c957aa85d 100644
--- a/src/compiler/simplified-operator.h
+++ b/src/compiler/simplified-operator.h
@@ -186,6 +186,8 @@ V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, NumberOperationHint);
 NumberOperationHint NumberOperationHintOf(const Operator* op)
     WARN_UNUSED_RESULT;
 
+int ParameterCountOf(const Operator* op) WARN_UNUSED_RESULT;
+
 PretenureFlag PretenureFlagOf(const Operator* op) WARN_UNUSED_RESULT;
 
 UnicodeEncoding UnicodeEncodingOf(const Operator*) WARN_UNUSED_RESULT;
@@ -355,6 +357,12 @@ class V8_EXPORT_PRIVATE SimplifiedOperatorBuilder final
   const Operator* ObjectIsString();
   const Operator* ObjectIsUndetectable();
 
+  // new-rest-parameter-elements
+  const Operator* NewRestParameterElements(int parameter_count);
+
+  // new-unmapped-arguments-elements
+  const Operator* NewUnmappedArgumentsElements(int parameter_count);
+
   // array-buffer-was-neutered buffer
   const Operator* ArrayBufferWasNeutered();