public void addLiveOut(int regV) {
    if (liveOut == null) {
      liveOut = SetFactory.makeLivenessSet(parent.getRegCount());
    }

    liveOut.add(regV);
  }
Adds {@code regV} to the live-out list for this block. This is called by the liveness analyzer.

@param regV register that is live-out for this block.
android/android_framework/dex-maker/src/main/java/com/android/dx/ssa/SsaBasicBlock.java