optIterator = new VM_OptGCMapIterator(registerLocations);
if (VM.BuildForOptCompiler) { optIterator = new VM_OptGCMapIterator(registerLocations); } else { optIterator = null; }
  public VM_GCMapIteratorGroup() {     registerLocations         = WordArray.create(VM_Constants.NUM_GPRS);        baselineIterator = new VM_BaselineGCMapIterator(registerLocations);    //-#if RVM_WITH_OPT_COMPILER    optIterator = new VM_OptGCMapIterator(registerLocations);    //-#endif    jniIterator = new VM_JNIGCMapIterator(registerLocations);    hardwareTrapIterator      = new VM_HardwareTrapGCMapIterator(registerLocations);  }