message: Print out field information in the show method
  Summary: Simple. We didn't print out field information for IRFieldInstructions.
diff: @@ -875,6 +875,9 @@ std::string show(const IRInstruction* insn) {
  if (insn->has_methods()) {
  ss << " "
  << show(static_cast<const IRMethodInstruction*>(insn)->get_method());
  + } else if (insn->has_fields()) {
  + ss << " "
  + << show(static_cast<const IRFieldInstruction*>(insn)->field());
  }
  if (opcode::has_range(insn->opcode())) {
  ss << " range base: " << insn->range_base() << ", "
  