C++ AsmPrinter::PrintAsmMemoryOperand方法代码示例

//.........这里部分代码省略.........
        PrintSpecial(MI, OS, Val.c_str());
        LastEmitted = StrEnd+1;
        break;
      }

      const char *IDStart = LastEmitted;
      const char *IDEnd = IDStart;
      while (*IDEnd >= '0' && *IDEnd <= '9') ++IDEnd;

      unsigned Val;
      if (StringRef(IDStart, IDEnd-IDStart).getAsInteger(10, Val))
        report_fatal_error("Bad $ operand number in inline asm string: '" +
                           Twine(AsmStr) + "'");
      LastEmitted = IDEnd;

      char Modifier[2] = { 0, 0 };

      if (HasCurlyBraces) {
        // If we have curly braces, check for a modifier character.  This
        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
        if (*LastEmitted == ':') {
          ++LastEmitted;    // Consume ':' character.
          if (*LastEmitted == 0)
            report_fatal_error("Bad ${:} expression in inline asm string: '" +
                               Twine(AsmStr) + "'");

          Modifier[0] = *LastEmitted;
          ++LastEmitted;    // Consume modifier character.
        }

        if (*LastEmitted != '}')
          report_fatal_error("Bad ${} expression in inline asm string: '" +
                             Twine(AsmStr) + "'");
        ++LastEmitted;    // Consume '}' character.
      }

      if (Val >= NumOperands-1)
        report_fatal_error("Invalid $ operand number in inline asm string: '" +
                           Twine(AsmStr) + "'");

      // Okay, we finally have a value number.  Ask the target to print this
      // operand!
      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
        unsigned OpNo = InlineAsm::MIOp_FirstOperand;

        bool Error = false;

        // Scan to find the machine operand number for the operand.
        for (; Val; --Val) {
          if (OpNo >= MI->getNumOperands()) break;
          unsigned OpFlags = MI->getOperand(OpNo).getImm();
          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
        }

	// We may have a location metadata attached to the end of the
	// instruction, and at no point should see metadata at any
	// other point while processing. It's an error if so.
        if (OpNo >= MI->getNumOperands() ||
	    MI->getOperand(OpNo).isMetadata()) {
          Error = true;
        } else {
          unsigned OpFlags = MI->getOperand(OpNo).getImm();
          ++OpNo;  // Skip over the ID number.

          if (Modifier[0] == 'l')  // labels are target independent
            // FIXME: What if the operand isn't an MBB, report error?
            OS << *MI->getOperand(OpNo).getMBB()->getSymbol();
          else {
            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
            if (InlineAsm::isMemKind(OpFlags)) {
              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
                                                Modifier[0] ? Modifier : 0,
                                                OS);
            } else {
              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
                                          Modifier[0] ? Modifier : 0, OS);
            }
          }
        }
        if (Error) {
          std::string msg;
          raw_string_ostream Msg(msg);
          Msg << "invalid operand in inline asm: '" << AsmStr << "'";
          MMI->getModule()->getContext().emitError(LocCookie, Msg.str());
        }
      }
      break;
    }
    }
  }
  OS << '\n' << (char)0;  // null terminate string.
  EmitInlineAsm(OS.str(), LocMD);

  // Emit the #NOAPP end marker.  This has to happen even if verbose-asm isn't
  // enabled, so we use EmitRawText.
  if (OutStreamer.hasRawTextSupport())
    OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
                            MAI->getInlineAsmEnd());
#endif // ANDROID_TARGET_BUILD
}