public RegisterSpecSet getStarts(int index) {
    RegisterSpecSet result = getStarts0(index);

    return (result != null) ? result : emptySet;
  }
Gets the register set associated with the start of the block with the given index. This returns
an empty set with the appropriate max size if no set was associated with the block in question.

@param index {@code >= 0;} the block index
@return {@code non-null;} the associated register set
android/android_framework/dex-maker/src/main/java/com/android/dx/ssa/LocalVariableInfo.java