src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp

*** 138,14 ***
    }
  }
  
  
  void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
-   assert_different_registers(obj, klass, len);
    Register tmp_encode_klass = LP64_ONLY(rscratch1) NOT_LP64(noreg);
!   // This assumes that all prototype bits fit in an int32_t
!   movptr(Address(obj, oopDesc::mark_offset_in_bytes ()), (int32_t)(intptr_t)markWord::prototype().value());
  #ifdef _LP64
    if (UseCompressedClassPointers) { // Take care not to kill klass
      movptr(t1, klass);
      encode_klass_not_null(t1, tmp_encode_klass);
      movl(Address(obj, oopDesc::klass_offset_in_bytes()), t1);
--- 138,14 ---
    }
  }
  
  
  void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
    Register tmp_encode_klass = LP64_ONLY(rscratch1) NOT_LP64(noreg);
!   assert_different_registers(obj, klass, len, t1, t2);
!   movptr(t1, Address(klass, Klass::prototype_header_offset()));
+   movptr(Address(obj, oopDesc::mark_offset_in_bytes()), t1);
  #ifdef _LP64
    if (UseCompressedClassPointers) { // Take care not to kill klass
      movptr(t1, klass);
      encode_klass_not_null(t1, tmp_encode_klass);
      movl(Address(obj, oopDesc::klass_offset_in_bytes()), t1);