//===- OptionalDiagnostic.h - An optional diagnostic ------------*- C++ -*-===//
 
//
 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 
// See https://llvm.org/LICENSE.txt for license information.
 
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
/// \file
 
/// Implements a partial diagnostic which may not be emitted.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_AST_OPTIONALDIAGNOSTIC_H
 
#define LLVM_CLANG_AST_OPTIONALDIAGNOSTIC_H
 
 
 
#include "clang/AST/APValue.h"
 
#include "clang/Basic/PartialDiagnostic.h"
 
#include "llvm/ADT/APFloat.h"
 
#include "llvm/ADT/APSInt.h"
 
#include "llvm/ADT/SmallVector.h"
 
#include "llvm/ADT/StringRef.h"
 
 
 
namespace clang {
 
 
 
/// A partial diagnostic which we might know in advance that we are not going
 
/// to emit.
 
class OptionalDiagnostic {
 
  PartialDiagnostic *Diag;
 
 
 
public:
 
  explicit OptionalDiagnostic(PartialDiagnostic *Diag = nullptr) : Diag(Diag) {}
 
 
 
  template <typename T> OptionalDiagnostic &operator<<(const T &v) {
 
    if (Diag)
 
      *Diag << v;
 
    return *this;
 
  }
 
 
 
  OptionalDiagnostic &operator<<(const llvm::APSInt &I) {
 
    if (Diag) {
 
      SmallVector<char, 32> Buffer;
 
      I.toString(Buffer);
 
      *Diag << StringRef(Buffer.data(), Buffer.size());
 
    }
 
    return *this;
 
  }
 
 
 
  OptionalDiagnostic &operator<<(const llvm::APFloat &F) {
 
    if (Diag) {
 
      // FIXME: Force the precision of the source value down so we don't
 
      // print digits which are usually useless (we don't really care here if
 
      // we truncate a digit by accident in edge cases).  Ideally,
 
      // APFloat::toString would automatically print the shortest
 
      // representation which rounds to the correct value, but it's a bit
 
      // tricky to implement. Could use std::to_chars.
 
      unsigned precision = llvm::APFloat::semanticsPrecision(F.getSemantics());
 
      precision = (precision * 59 + 195) / 196;
 
      SmallVector<char, 32> Buffer;
 
      F.toString(Buffer, precision);
 
      *Diag << StringRef(Buffer.data(), Buffer.size());
 
    }
 
    return *this;
 
  }
 
 
 
  OptionalDiagnostic &operator<<(const llvm::APFixedPoint &FX) {
 
    if (Diag) {
 
      SmallVector<char, 32> Buffer;
 
      FX.toString(Buffer);
 
      *Diag << StringRef(Buffer.data(), Buffer.size());
 
    }
 
    return *this;
 
  }
 
};
 
 
 
} // namespace clang
 
 
 
#endif