code: public boolean containsInstructionWithOffset(int offset) {
          Iterator<InstructionHandle> i = instructionIterator();
          while (i.hasNext()) {
              if (i.next().getPosition() == offset) {
                  return true;
              }
          }
          return false;
      }
docs: Return whether or not the basic block contains the instruction with the
  given bytecode offset.
  
  @param offset
  the bytecode offset
  @return true if the block contains an instruction with the given offset,
  false if it does not