--- a/src/cpu/x86/vm/c1_LIRGenerator_x86.cpp	Thu Oct 01 12:22:20 2015 +0200
+++ b/src/cpu/x86/vm/c1_LIRGenerator_x86.cpp	Thu Oct 01 12:58:23 2015 +0200
@@ -306,8 +306,9 @@
   if (obj_store && UseShenandoahGC) {
     if (! val->is_register()) {
       assert(val->is_constant(), "expect constant");
+    } else {
+      val = shenandoah_read_barrier(val, NULL, true);
     }
-    val = shenandoah_read_barrier(val, NULL, true);
   }
 
   // emit array address setup early so it schedules better

--- a/src/share/vm/c1/c1_LIRGenerator.cpp	Thu Oct 01 12:22:20 2015 +0200
+++ b/src/share/vm/c1/c1_LIRGenerator.cpp	Thu Oct 01 12:58:23 2015 +0200
@@ -1435,7 +1435,6 @@
     case BarrierSet::ShenandoahBarrierSet:
       G1SATBCardTableModRef_pre_barrier(addr_opr, pre_val, do_load, patch, info);
       break;
-
 #endif // INCLUDE_ALL_GCS
     case BarrierSet::CardTableForRS:
     case BarrierSet::CardTableExtension:
@@ -1739,13 +1738,12 @@
 
   obj = shenandoah_write_barrier(obj, info, x->needs_null_check());
   LIR_Opr val = value.result();
-  if (is_oop) {
+  if (is_oop && UseShenandoahGC) {
     if (! val->is_register()) {
-      LIR_Opr tmp = new_register(T_OBJECT);
-      __ move(val, tmp);
-      val = tmp;
+      assert(val->is_constant(), "expect constant");
+    } else {
+      val = shenandoah_read_barrier(val, NULL, true);
     }
-    val = shenandoah_read_barrier(val, NULL, true);
   }
 
   LIR_Address* address;
@@ -1819,6 +1817,7 @@
                   x->is_static() ?  "static" : "field", x->printable_bci());
   }
 #endif
+
   LIR_Opr obj = object.result();
   bool stress_deopt = StressLoopInvariantCodeMotion && info && info->deoptimize_on_exception();
   if (x->needs_null_check() &&