Method parseSrcComment

libyul/AsmParser.cpp:200–298

}

std::optional<std::pair<std::string_view, SourceLocation>> Parser::parseSrcComment(
	std::string_view const _arguments,
	langutil::SourceLocation const& _commentLocation
)
{
	CharStream argumentStream(std::string(_arguments), "");
	Scanner scanner(argumentStream, ScannerKind::SpecialComment);

	std::string_view tail{_arguments.substr(_arguments.size())};
	auto const parseLocationComponent = [](Scanner& _scanner, bool expectTrailingColon) -> std::optional<std::string>
	{
		bool negative = false;
		if (_scanner.currentToken() == Token::Sub)
		{
			negative = true;
			_scanner.next();
		}
		if (_scanner.currentToken() != Token::Number)
			return std::nullopt;
		if (expectTrailingColon && _scanner.peekNextToken() != Token::Colon)
			return std::nullopt;
		if (!isValidDecimal(_scanner.currentLiteral()))
			return std::nullopt;
		std::string decimal = (negative ? "-" : "") + _scanner.currentLiteral();
		_scanner.next();
		if (expectTrailingColon)
			_scanner.next();
		return decimal;
	};
	std::optional<std::string> rawSourceIndex = parseLocationComponent(scanner, true);
	std::optional<std::string> rawStart = parseLocationComponent(scanner, true);
	std::optional<std::string> rawEnd = parseLocationComponent(scanner, false);

	size_t const snippetStart = static_cast<size_t>(scanner.currentLocation().start);
	bool const locationScannedSuccessfully = rawSourceIndex && rawStart && rawEnd;
	bool const locationIsWhitespaceSeparated =
		scanner.peekNextToken() == Token::EOS ||
		(snippetStart > 0 && langutil::isWhiteSpace(_arguments[snippetStart - 1]));

	if (!locationScannedSuccessfully || !locationIsWhitespaceSeparated)
	{
		m_errorReporter.syntaxError(
			8387_error,
			_commentLocation,
			"Invalid values in source location mapping. Could not parse location specification."
		);
		return std::nullopt;
	}

	// captures error cases `"test` (illegal end quote) and `"test\` (illegal escape sequence / dangling backslash)
	bool const illegalLiteral = scanner.currentToken() == Token::Illegal && (scanner.currentError() == ScannerError::IllegalStringEndQuote || scanner.currentError() == ScannerError::IllegalEscapeSequence);
	if (scanner.currentToken() == Token::StringLiteral || illegalLiteral)
		tail = _arguments.substr(static_cast<size_t>(scanner.currentLocation().end));
	else
		tail = _arguments.substr(static_cast<size_t>(scanner.currentLocation().start));

	// Other scanner errors may occur if there is no string literal which follows
	// (f.ex. IllegalHexDigit, IllegalCommentTerminator), but these are ignored