void IncorrectRoundings::registerMatchers(MatchFinder *MatchFinder) {
  // Match a floating literal with value 0.5.
  auto FloatHalf = floatLiteral(floatHalf());

  // Match a floating point expression.
  auto FloatType = expr(hasType(realFloatingPointType()));

  // Match a floating literal of 0.5 or a floating literal of 0.5 implicitly.
  // cast to floating type.
  auto FloatOrCastHalf =
      anyOf(FloatHalf, implicitCastExpr(FloatType, has(FloatHalf)));

  // Match if either the LHS or RHS is a floating literal of 0.5 or a floating
  // literal of 0.5 and the other is of type double or vice versa.
  auto OneSideHalf = anyOf(allOf(hasLHS(FloatOrCastHalf), hasRHS(FloatType)),
                           allOf(hasRHS(FloatOrCastHalf), hasLHS(FloatType)));

  // Find expressions of cast to int of the sum of a floating point expression
  // and 0.5.
  MatchFinder->addMatcher(
      implicitCastExpr(
          hasImplicitDestinationType(isInteger()),
          ignoringParenCasts(binaryOperator(hasOperatorName("+"), OneSideHalf)))
          .bind("CastExpr"),
      this);
}
llvm::Optional<std::string>
stripFloatCast(const ast_matchers::MatchFinder::MatchResult &Result,
               const Expr &Node) {
  if (const Expr *MaybeCastArg = selectFirst<const Expr>(
          "cast_arg",
          match(expr(anyOf(cxxStaticCastExpr(
                               hasDestinationType(realFloatingPointType()),
                               hasSourceExpression(expr().bind("cast_arg"))),
                           cStyleCastExpr(
                               hasDestinationType(realFloatingPointType()),
                               hasSourceExpression(expr().bind("cast_arg"))),
                           cxxFunctionalCastExpr(
                               hasDestinationType(realFloatingPointType()),
                               hasSourceExpression(expr().bind("cast_arg"))))),
                Node, *Result.Context)))
    return tooling::fixit::getText(*MaybeCastArg, *Result.Context).str();

  return llvm::None;
}
/// Returns `true` if `Node` is a value which evaluates to a literal `0`.
bool IsLiteralZero(const MatchFinder::MatchResult &Result, const Expr &Node) {
  auto ZeroMatcher =
      anyOf(integerLiteral(equals(0)), floatLiteral(equals(0.0)));

  // Check to see if we're using a zero directly.
  if (selectFirst<const clang::Expr>(
          "val", match(expr(ignoringImpCasts(ZeroMatcher)).bind("val"), Node,
                       *Result.Context)) != nullptr)
    return true;

  // Now check to see if we're using a functional cast with a scalar
  // initializer expression, e.g. `int{0}`.
  if (selectFirst<const clang::Expr>(
          "val", match(cxxFunctionalCastExpr(
                           hasDestinationType(
                               anyOf(isInteger(), realFloatingPointType())),
                           hasSourceExpression(initListExpr(
                               hasInit(0, ignoringParenImpCasts(ZeroMatcher)))))
                           .bind("val"),
                       Node, *Result.Context)) != nullptr)
    return true;

  return false;
}
void FloatLoopCounter::registerMatchers(MatchFinder *Finder) {
  Finder->addMatcher(
      forStmt(hasIncrement(expr(hasType(realFloatingPointType())))).bind("for"),
      this);
}