escapeSummary = analyzer.simpleEscapeAnalysis(ir);
  void initialize(OPT_IR ir) {    this.ir = ir;    relocated = new HashSet();    if (ir.IRStage == OPT_IR.HIR) {      OPT_SimpleEscape analyzer = new OPT_SimpleEscape();      escapeSummary = analyzer.simpleEscapeAnalysis(ir);    }    // Note: the following unfactors the CFG    new OPT_DominatorsPhase(true).perform(ir);    OPT_Dominators.computeApproxPostdominators(ir);    dominator = ir.HIRInfo.dominatorTree;    if (DEBUG) VM.sysWrite (""+dominator.toString()+"\n");    int instructions = ir.numberInstructions();    ssad = ir.HIRInfo.SSADictionary;        OPT_DefUse.computeDU(ir);    ssad.recomputeArrayDU();    // also number implicit heap phis    OPT_BasicBlockEnumeration e = ir.getBasicBlocks();    while (e.hasMoreElements()) {      OPT_BasicBlock b = e.next();      Enumeration pe = ssad.getHeapPhiInstructions(b);      while (pe.hasMoreElements()) {        OPT_Instruction inst = (OPT_Instruction)pe.nextElement();        inst.scratch = instructions++;        inst.scratchObject = null;      }    }    state = new int[instructions];    origBlock = new OPT_BasicBlock[instructions];    block = new OPT_BasicBlock[instructions];    earlyPos = new OPT_Instruction[instructions];    e = ir.getBasicBlocks();    while (e.hasMoreElements()) {      OPT_BasicBlock b = e.next();      Enumeration ie = ssad.getAllInstructions(b);      while (ie.hasMoreElements()) {        OPT_Instruction inst = (OPT_Instruction)ie.nextElement();        setBlock(inst, b);        setOrigBlock(inst, b);        setState(inst, initial);      }    }    if (ir.IRStage == OPT_IR.HIR) {      e = ir.getBasicBlocks();      while (e.hasMoreElements()) {        OPT_BasicBlock b = e.next();                if (ir.options.FREQ_FOCUS_EFFORT && b.getInfrequent()) continue;        Enumeration ie = ssad.getAllInstructions(b);        while (ie.hasMoreElements()) {          OPT_Instruction inst = (OPT_Instruction)ie.nextElement();          while (simplify (inst, b));        }      }      ssad.recomputeArrayDU();    }  }