constructor(instrumentationData={}, viaIR){
    this.instrumentationData = instrumentationData;

    this.validOpcodes = this._getOpcodes(viaIR);
    this.lastHash = null;
    this.viaIR = viaIR;
    this.pcZeroCounter = 0;
    this.lastPcZeroCount = 0;
  }
Writes data from the VM step to the in-memory
coverage map constructed by the Instrumenter.