--- a/src/cpu/x86/vm/c1_MacroAssembler_x86.cpp	Fri Feb 24 18:30:42 2012 -0800
+++ b/src/cpu/x86/vm/c1_MacroAssembler_x86.cpp	Mon Feb 27 13:10:13 2012 +0100
@@ -156,7 +156,7 @@
   assert_different_registers(obj, klass, len);
   if (UseBiasedLocking && !len->is_valid()) {
     assert_different_registers(obj, klass, len, t1, t2);
-    movptr(t1, Address(klass, Klass::prototype_header_offset_in_bytes() + klassOopDesc::klass_part_offset_in_bytes()));
+    movptr(t1, Address(klass, Klass::prototype_header_offset()));
     movptr(Address(obj, oopDesc::mark_offset_in_bytes()), t1);
   } else {
     // This assumes that all prototype bits fit in an int32_t
@@ -389,6 +389,16 @@
 
 
 void C1_MacroAssembler::verified_entry() {
+  if (C1Breakpoint || VerifyFPU || !UseStackBanging) {
+    // Verified Entry first instruction should be 5 bytes long for correct
+    // patching by patch_verified_entry().
+    //
+    // C1Breakpoint and VerifyFPU have one byte first instruction.
+    // Also first instruction will be one byte "push(rbp)" if stack banging
+    // code is not generated (see build_frame() above).
+    // For all these cases generate long instruction first.
+    fat_nop();
+  }
   if (C1Breakpoint)int3();
   // build frame
   verify_FPU(0, "method_entry");