[stubs] ApiCallbackDescriptor cleanup - make it independent on the number of JS parameters.

src/fast-accessor-assembler.cc

Index: src/fast-accessor-assembler.cc
diff --git a/src/fast-accessor-assembler.cc b/src/fast-accessor-assembler.cc
index ebaab9a529de17f8d1a479e92cb97a2dae9913c0..a9cde70a5345c1d34c7be9269819000576d30819 100644
--- a/src/fast-accessor-assembler.cc
+++ b/src/fast-accessor-assembler.cc
@@ -179,27 +179,35 @@ FastAccessorAssembler::ValueId FastAccessorAssembler::Call(
                              ExternalReference::DIRECT_API_CALL, isolate());
 
   // Create & call API callback via stub.
-  CallApiCallbackStub stub(isolate(), 1, true, true);
-  DCHECK_EQ(5, stub.GetCallInterfaceDescriptor().GetParameterCount());
-  DCHECK_EQ(1, stub.GetCallInterfaceDescriptor().GetStackParameterCount());
+  const int kJSParameterCount = 1;
+  CallApiCallbackStub stub(isolate(), kJSParameterCount, true, true);
+  CallInterfaceDescriptor descriptor = stub.GetCallInterfaceDescriptor();
+  DCHECK_EQ(4, descriptor.GetParameterCount());
+  DCHECK_EQ(0, descriptor.GetStackParameterCount());
   // TODO(vogelheim): There is currently no clean way to retrieve the context
   //     parameter for a stub and the implementation details are hidden in
   //     compiler/*. The context_paramter is computed as:
   //       Linkage::GetJSCallContextParamIndex(descriptor->JSParameterCount())
-  const int context_parameter = 3;
-  Node* call = assembler_->CallStub(
-      stub.GetCallInterfaceDescriptor(),
-      assembler_->HeapConstant(stub.GetCode()),
-      assembler_->Parameter(context_parameter),
-
-      // Stub/register parameters:
-      assembler_->UndefinedConstant(), /* callee (there's no JSFunction) */
-      assembler_->UndefinedConstant(), /* call_data (undefined) */
-      assembler_->Parameter(0), /* receiver (same as holder in this case) */
-      assembler_->ExternalConstant(callback), /* API callback function */
-
-      // JS arguments, on stack:
-      FromId(arg));
+  const int kContextParameter = 3;
+  Node* context = assembler_->Parameter(kContextParameter);
+  Node* target = assembler_->HeapConstant(stub.GetCode());
+
+  int param_count = descriptor.GetParameterCount();
+  Node** args = zone()->NewArray<Node*>(param_count + 1 + kJSParameterCount);
+  // Stub/register parameters:
+  args[0] = assembler_->UndefinedConstant();  // callee (there's no JSFunction)
+  args[1] = assembler_->UndefinedConstant();  // call_data (undefined)
+  args[2] = assembler_->Parameter(0);  // receiver (same as holder in this case)
+  args[3] = assembler_->ExternalConstant(callback);  // API callback function
+
+  // JS arguments, on stack:
+  args[4] = FromId(arg);
+
+  // Context.
+  args[5] = context;
+
+  Node* call =
+      assembler_->CallStubN(descriptor, kJSParameterCount, target, args);
 
   return FromRaw(call);
 }