Merged: Don't call FastNewFunctionContextStub if context is bigger than kMaxRegularHeapObjectSize.

src/compiler/js-generic-lowering.cc

Index: src/compiler/js-generic-lowering.cc
diff --git a/src/compiler/js-generic-lowering.cc b/src/compiler/js-generic-lowering.cc
index 69526cd7eae8d43227c820e3842c05c01c7377e2..812d3e7bcee0d1d5843f450ea5b8b45f5a3a4b8b 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -444,9 +444,13 @@ void JSGenericLowering::LowerJSCreateFunctionContext(Node* node) {
   int const slot_count = OpParameter<int>(node->op());
   CallDescriptor::Flags flags = FrameStateFlagForCall(node);
 
-  Callable callable = CodeFactory::FastNewFunctionContext(isolate());
-  node->InsertInput(zone(), 1, jsgraph()->Int32Constant(slot_count));
-  ReplaceWithStubCall(node, callable, flags);
+  if (slot_count <= FastNewFunctionContextStub::kMaximumSlots) {
+    Callable callable = CodeFactory::FastNewFunctionContext(isolate());
+    node->InsertInput(zone(), 1, jsgraph()->Int32Constant(slot_count));
+    ReplaceWithStubCall(node, callable, flags);
+  } else {
+    ReplaceWithRuntimeCall(node, Runtime::kNewFunctionContext);
+  }
 }