ir.HIRInfo.dominatorsAreComputed = false;
  final public void perform(OPT_IR ir) {    this.ir = ir;    translateFromSSA(ir);	 // reset ir.SSADictionary 	 ir.HIRInfo.SSADictionary = null;	 // reset ssa options	 ir.actualSSAOptions = null;    branchOpts.perform(ir, true);  }