onnxruntime-extensions/base/narrow.h

80 строки
2.7 KiB
C++

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.
#pragma once
// ort_extensions::narrow() is like gsl::narrow() but it is also available when exceptions are disabled.
#if !defined(OCOS_NO_EXCEPTIONS)
#include "gsl/narrow"
namespace ort_extensions {
using gsl::narrow;
} // namespace ort_extensions
#else // !defined(OCOS_NO_EXCEPTIONS)
#include <cstdio> // std::fprintf
#include <exception> // std::terminate
#include <type_traits>
#include "gsl/util" // gsl::narrow_cast
namespace ort_extensions {
namespace detail {
[[noreturn]] inline void OnNarrowingError() noexcept {
std::fprintf(stderr, "%s", "narrowing error\n");
std::terminate();
}
} // namespace detail
// This implementation of ort_extensions::narrow was copied and adapted from:
// https://github.com/microsoft/onnxruntime/blob/77b455b969db15d911cd6de5009f3a30fb42c531/include/onnxruntime/core/common/narrow.h
// which was copied and adapted from
// https://github.com/microsoft/GSL/blob/a3534567187d2edc428efd3f13466ff75fe5805c/include/gsl/narrow
// narrow() : a checked version of narrow_cast() that terminates if the cast changed the value
template <class T, class U, typename std::enable_if<std::is_arithmetic<T>::value>::type* = nullptr>
// clang-format off
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
// clang-format on
constexpr T narrow(U u) noexcept {
constexpr const bool is_different_signedness =
(std::is_signed<T>::value != std::is_signed<U>::value);
// clang-format off
GSL_SUPPRESS(es.103) // NO-FORMAT: attribute // don't overflow
GSL_SUPPRESS(es.104) // NO-FORMAT: attribute // don't underflow
GSL_SUPPRESS(p.2) // NO-FORMAT: attribute // don't rely on undefined behavior
// clang-format on
const T t = gsl::narrow_cast<T>(u); // While this is technically undefined behavior in some cases (i.e., if the source value is of floating-point type
// and cannot fit into the destination integral type), the resultant behavior is benign on the platforms
// that we target (i.e., no hardware trap representations are hit).
if (static_cast<U>(t) != u || (is_different_signedness && ((t < T{}) != (u < U{})))) {
detail::OnNarrowingError();
}
return t;
}
template <class T, class U, typename std::enable_if<!std::is_arithmetic<T>::value>::type* = nullptr>
// clang-format off
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
// clang-format on
constexpr T narrow(U u) noexcept {
const T t = gsl::narrow_cast<T>(u);
if (static_cast<U>(t) != u) {
detail::OnNarrowingError();
}
return t;
}
} // namespace ort_extensions
#endif // !defined(OCOS_NO_EXCEPTIONS)