VM_Address tgt, int locationMetadata, int mode)
VM_Address tgt, int locationMetadata, int context)
  public final void writeBarrier(VM_Address src, VM_Address slot,                                 VM_Address tgt, int locationMetadata, int mode)     throws VM_PragmaInline {    TraceGenerator.processPointerUpdate(mode == PUTFIELD_WRITE_BARRIER,                                        src, slot, tgt);    VM_Magic.setMemoryAddress(slot, tgt, locationMetadata);  }