if (VM.VerifyAssertions) VM.assert (def != null);
if (VM.VerifyAssertions) VM._assert (def != null);
  OPT_Instruction scheduleHeapDefsEarly (OPT_HeapOperand[] op, 					 OPT_Instruction earlyPos, 					 OPT_Instruction me) {    if (op == null) return  earlyPos;        for (int i = 0; i < op.length; ++i) {      OPT_Instruction def = definingInstruction(op[i]);      //  if (me.isImplicitLoad() || me.isImplicitStore())//  	def = _getRealDef(def, me)//  	  ;//        else if (me.isPEI()) //  	def = _getRealExceptionDef(def)      //  ;            if (VM.VerifyAssertions) VM.assert (def != null);      earlyPos = maxDominatorDepth (scheduleEarly (def), earlyPos);          }    return  earlyPos;  }