[Interpreter] Add support for JS calls.

src/x64/interface-descriptors-x64.cc

Index: src/x64/interface-descriptors-x64.cc
diff --git a/src/x64/interface-descriptors-x64.cc b/src/x64/interface-descriptors-x64.cc
index d9f6d05a1e9a2424507d4c48751afbc020dd2ed0..752e2a94182afd4e86c62684d49731e915d0abaf 100644
--- a/src/x64/interface-descriptors-x64.cc
+++ b/src/x64/interface-descriptors-x64.cc
@@ -381,6 +381,17 @@ void MathRoundVariantCallFromOptimizedCodeDescriptor::
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
+
+
+void PushArgsAndCallDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  Register registers[] = {
+      rax,  // argument count (including receiver)
+      rbx,  // address of first argument
+      rdi   // the target callable to be call
+  };
+  data->InitializePlatformSpecific(arraysize(registers), registers);
+}
 }  // namespace internal
 }  // namespace v8