--- old/src/hotspot/share/opto/callGenerator.cpp	2019-03-14 14:00:02.819847601 +0100
+++ new/src/hotspot/share/opto/callGenerator.cpp	2019-03-14 14:00:02.643846926 +0100
@@ -1136,7 +1136,7 @@
   if (!method()->is_static()) {
     // We need an explicit receiver null_check before checking its type in predicate.
     // We share a map with the caller, so his JVMS gets adjusted.
-    Node* receiver = kit.null_check_receiver_before_call(method());
+    kit.null_check_receiver_before_call(method());
     if (kit.stopped()) {
       return kit.transfer_exceptions_into_jvms();
     }
--- old/src/hotspot/share/opto/graphKit.cpp	2019-03-14 14:00:03.251849259 +0100
+++ new/src/hotspot/share/opto/graphKit.cpp	2019-03-14 14:00:03.095848660 +0100
@@ -1798,10 +1798,6 @@
       // We don't pass value type arguments by reference but instead
       // pass each field of the value type
       ValueTypeNode* vt = arg->isa_ValueType();
-      if (vt == NULL) {
-        // TODO why is that?? Shouldn't we always see a valuetype node here?
-        vt = ValueTypeNode::make_from_oop(this, arg, t->value_klass());
-      }
       vt->pass_fields(this, call, sig_cc, idx);
       // If a value type argument is passed as fields, attach the Method* to the call site
       // to be able to access the extended signature later via attached_method_before_pc().
--- old/src/hotspot/share/opto/graphKit.hpp	2019-03-14 14:00:03.727851085 +0100
+++ new/src/hotspot/share/opto/graphKit.hpp	2019-03-14 14:00:03.563850455 +0100
@@ -37,6 +37,7 @@
 #include "opto/phaseX.hpp"
 #include "opto/subnode.hpp"
 #include "opto/type.hpp"
+#include "opto/valuetypenode.hpp"
 #include "runtime/deoptimization.hpp"
 
 class BarrierSetC2;
@@ -678,7 +679,7 @@
 
   // Do a null check on the receiver as it would happen before the call to
   // callee (with all arguments still on the stack).
-  Node* null_check_receiver_before_call(ciMethod* callee) {
+  Node* null_check_receiver_before_call(ciMethod* callee, bool replace_value = true) {
     assert(!callee->is_static(), "must be a virtual method");
     if (argument(0)->is_ValueType()) {
       return argument(0);
@@ -690,6 +691,16 @@
     inc_sp(nargs);
     Node* n = null_check_receiver();
     dec_sp(nargs);
+    // Scalarize value type receiver
+    const Type* recv_type = gvn().type(n);
+    if (recv_type->is_valuetypeptr() && recv_type->value_klass()->is_scalarizable()) {
+      assert(!recv_type->maybe_null(), "should never be null");
+      ValueTypeNode* vt = ValueTypeNode::make_from_oop(this, n, recv_type->value_klass());
+      if (replace_value) {
+        replace_in_map(n, vt);
+      }
+      n = vt;
+    }
     return n;
   }
 
--- old/src/hotspot/share/opto/library_call.cpp	2019-03-14 14:00:04.259853126 +0100
+++ new/src/hotspot/share/opto/library_call.cpp	2019-03-14 14:00:04.071852404 +0100
@@ -2651,7 +2651,7 @@
       p = gvn().transform(new CastP2XNode(NULL, p));
       p = ConvX2UL(p);
     }
-    if (field != NULL && field->is_flattenable()&& !field->is_flattened()) {
+    if (field != NULL && field->is_flattenable() && !field->is_flattened()) {
       // Load a non-flattened but flattenable value type from memory
       if (value_type->value_klass()->is_scalarizable()) {
         p = ValueTypeNode::make_from_oop(this, p, value_type->value_klass());
--- old/src/hotspot/share/opto/parse.hpp	2019-03-14 14:00:04.795855181 +0100
+++ new/src/hotspot/share/opto/parse.hpp	2019-03-14 14:00:04.627854537 +0100
@@ -529,7 +529,7 @@
   bool static_field_ok_in_clinit(ciField *field, ciMethod *method);
 
   // common code for actually performing the load or store
-  void do_get_xxx(Node* obj, ciField* field, bool is_field);
+  void do_get_xxx(Node* obj, ciField* field);
   void do_put_xxx(Node* obj, ciField* field, bool is_field);
 
   // implementation of object creation bytecodes
--- old/src/hotspot/share/opto/parse1.cpp	2019-03-14 14:00:05.179856655 +0100
+++ new/src/hotspot/share/opto/parse1.cpp	2019-03-14 14:00:05.031856087 +0100
@@ -1198,7 +1198,7 @@
   // If this is an inlined method, we may have to do a receiver null check.
   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
     GraphKit kit(_caller);
-    kit.null_check_receiver_before_call(method());
+    kit.null_check_receiver_before_call(method(), false);
     _caller = kit.transfer_exceptions_into_jvms();
     if (kit.stopped()) {
       _exits.add_exception_states_from(_caller);
--- old/src/hotspot/share/opto/parse3.cpp	2019-03-14 14:00:05.583858204 +0100
+++ new/src/hotspot/share/opto/parse3.cpp	2019-03-14 14:00:05.431857621 +0100
@@ -134,7 +134,7 @@
 
     if (is_get) {
       (void) pop();  // pop receiver before getting
-      do_get_xxx(obj, field, is_field);
+      do_get_xxx(obj, field);
     } else {
       do_put_xxx(obj, field, is_field);
       if (stopped()) {
@@ -146,14 +146,14 @@
     const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
     obj = _gvn.makecon(tip);
     if (is_get) {
-      do_get_xxx(obj, field, is_field);
+      do_get_xxx(obj, field);
     } else {
       do_put_xxx(obj, field, is_field);
     }
   }
 }
 
-void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
+void Parse::do_get_xxx(Node* obj, ciField* field) {
   BasicType bt = field->layout_type();
 
   // Does this field have a constant value?  If so, just push the value.
@@ -211,6 +211,7 @@
         ciObject* val = mirror->field_value(field).as_object();
         if (!val->is_null_object()) {
           type = type->join_speculative(TypePtr::NOTNULL);
+          flattenable = true; // Null-free, treat as flattenable
         }
       }
     }