[turbofan] Lower JSLoadMessage/JSStoreMessage earlier.

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 64e50d6f76886e7b9e41e23c30edae84f41ad104..ee844e9ee282770c15047c8ab56392eea707f9eb 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -546,24 +546,12 @@ void JSGenericLowering::LowerJSForInPrepare(Node* node) {
 }
 
 void JSGenericLowering::LowerJSLoadMessage(Node* node) {
-  ExternalReference message_address =
-      ExternalReference::address_of_pending_message_obj(isolate());
-  node->RemoveInput(NodeProperties::FirstContextIndex(node));
-  node->InsertInput(zone(), 0, jsgraph()->ExternalConstant(message_address));
-  node->InsertInput(zone(), 1, jsgraph()->IntPtrConstant(0));
-  NodeProperties::ChangeOp(node, machine()->Load(MachineType::AnyTagged()));
+  UNREACHABLE();  // Eliminated in typed lowering.
 }
 
 
 void JSGenericLowering::LowerJSStoreMessage(Node* node) {
-  ExternalReference message_address =
-      ExternalReference::address_of_pending_message_obj(isolate());
-  node->RemoveInput(NodeProperties::FirstContextIndex(node));
-  node->InsertInput(zone(), 0, jsgraph()->ExternalConstant(message_address));
-  node->InsertInput(zone(), 1, jsgraph()->IntPtrConstant(0));
-  StoreRepresentation representation(MachineRepresentation::kTagged,
-                                     kNoWriteBarrier);
-  NodeProperties::ChangeOp(node, machine()->Store(representation));
+  UNREACHABLE();  // Eliminated in typed lowering.
 }
 
 void JSGenericLowering::LowerJSLoadModule(Node* node) {