private BitSet getPreds(SsaBasicBlock block) {
    if (postdom) {
      return block.getSuccessors();
    } else {
      return block.getPredecessors();
    }
  }
Constructs a fully-initialized instance. (This method exists so as to avoid calling a large
amount of code in the constructor.)

@param meth {@code non-null;} method to process
@param domInfos {@code non-null;} the raw dominator info
@param postdom true for postdom information, false for normal dom info
android/android_framework/dex-maker/src/main/java/com/android/dx/ssa/Dominators.java