--- old/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp	2018-09-26 10:01:40.414752605 -0400
+++ new/src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp	2018-09-26 10:01:38.866662529 -0400
@@ -65,7 +65,7 @@
   // test if object header is still the same (i.e. unlocked), and if so, store the
   // displaced header address in the object header - if it is not the same, get the
   // object header instead
-  if (os::is_MP()) MacroAssembler::lock(); // must be immediately before cmpxchg!
+  MacroAssembler::lock(); // must be immediately before cmpxchg!
   cmpxchgptr(disp_hdr, Address(obj, hdr_offset));
   // if the object header was the same, we're done
   if (PrintBiasedLockingStatistics) {
@@ -126,7 +126,7 @@
   // test if object header is pointing to the displaced header, and if so, restore
   // the displaced header in the object - if the object header is not pointing to
   // the displaced header, get the object header instead
-  if (os::is_MP()) MacroAssembler::lock(); // must be immediately before cmpxchg!
+  MacroAssembler::lock(); // must be immediately before cmpxchg!
   cmpxchgptr(hdr, Address(obj, hdr_offset));
   // if the object header was not pointing to the displaced header,
   // we do unlocking via runtime call