From 35f7829af10c61e33dd2e2a7a015058e11a11ea0 Mon Sep 17 00:00:00 2001 From: Stanislaw Halik Date: Sat, 25 Mar 2017 14:17:07 +0100 Subject: update --- eigen/Eigen/src/Core/util/IntegralConstant.h | 270 +++++++++++++++++++++++++++ 1 file changed, 270 insertions(+) create mode 100644 eigen/Eigen/src/Core/util/IntegralConstant.h (limited to 'eigen/Eigen/src/Core/util/IntegralConstant.h') diff --git a/eigen/Eigen/src/Core/util/IntegralConstant.h b/eigen/Eigen/src/Core/util/IntegralConstant.h new file mode 100644 index 0000000..78a4705 --- /dev/null +++ b/eigen/Eigen/src/Core/util/IntegralConstant.h @@ -0,0 +1,270 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2017 Gael Guennebaud +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + + +#ifndef EIGEN_INTEGRAL_CONSTANT_H +#define EIGEN_INTEGRAL_CONSTANT_H + +namespace Eigen { + +namespace internal { + +template class FixedInt; +template class VariableAndFixedInt; + +/** \internal + * \class FixedInt + * + * This class embeds a compile-time integer \c N. + * + * It is similar to c++11 std::integral_constant but with some additional features + * such as: + * - implicit conversion to int + * - arithmetic and some bitwise operators: -, +, *, /, %, &, | + * - c++98/14 compatibility with fix and fix() syntax to define integral constants. + * + * It is strongly discouraged to directly deal with this class FixedInt. Instances are expcected to + * be created by the user using Eigen::fix or Eigen::fix(). In C++98-11, the former syntax does + * not create a FixedInt instance but rather a point to function that needs to be \em cleaned-up + * using the generic helper: + * \code + * internal::cleanup_index_type::type + * internal::cleanup_index_type::type + * \endcode + * where T can a FixedInt, a pointer to function FixedInt (*)(), or numerous other integer-like representations. + * \c DynamicKey is either Dynamic (default) or DynamicIndex and used to identify true compile-time values. + * + * For convenience, you can extract the compile-time value \c N in a generic way using the following helper: + * \code + * internal::get_fixed_value::value + * \endcode + * that will give you \c N if T equals FixedInt or FixedInt (*)(), and \c DefaultVal if T does not embed any compile-time value (e.g., T==int). + * + * \sa fix, class VariableAndFixedInt + */ +template class FixedInt +{ +public: + static const int value = N; + operator int() const { return value; } + FixedInt() {} + FixedInt( VariableAndFixedInt other) { + EIGEN_ONLY_USED_FOR_DEBUG(other); + eigen_internal_assert(int(other)==N); + } + + FixedInt<-N> operator-() const { return FixedInt<-N>(); } + template + FixedInt operator+( FixedInt) const { return FixedInt(); } + template + FixedInt operator-( FixedInt) const { return FixedInt(); } + template + FixedInt operator*( FixedInt) const { return FixedInt(); } + template + FixedInt operator/( FixedInt) const { return FixedInt(); } + template + FixedInt operator%( FixedInt) const { return FixedInt(); } + template + FixedInt operator|( FixedInt) const { return FixedInt(); } + template + FixedInt operator&( FixedInt) const { return FixedInt(); } + +#if EIGEN_HAS_CXX14 + // Needed in C++14 to allow fix(): + FixedInt operator() () const { return *this; } + + VariableAndFixedInt operator() (int val) const { return VariableAndFixedInt(val); } +#else + FixedInt ( FixedInt (*)() ) {} +#endif + +#if EIGEN_HAS_CXX11 + FixedInt(std::integral_constant) {} +#endif +}; + +/** \internal + * \class VariableAndFixedInt + * + * This class embeds both a compile-time integer \c N and a runtime integer. + * Both values are supposed to be equal unless the compile-time value \c N has a special + * value meaning that the runtime-value should be used. Depending on the context, this special + * value can be either Eigen::Dynamic (for positive quantities) or Eigen::DynamicIndex (for + * quantities that can be negative). + * + * It is the return-type of the function Eigen::fix(int), and most of the time this is the only + * way it is used. It is strongly discouraged to directly deal with instances of VariableAndFixedInt. + * Indeed, in order to write generic code, it is the responsibility of the callee to properly convert + * it to either a true compile-time quantity (i.e. a FixedInt), or to a runtime quantity (e.g., an Index) + * using the following generic helper: + * \code + * internal::cleanup_index_type::type + * internal::cleanup_index_type::type + * \endcode + * where T can be a template instantiation of VariableAndFixedInt or numerous other integer-like representations. + * \c DynamicKey is either Dynamic (default) or DynamicIndex and used to identify true compile-time values. + * + * For convenience, you can also extract the compile-time value \c N using the following helper: + * \code + * internal::get_fixed_value::value + * \endcode + * that will give you \c N if T equals VariableAndFixedInt, and \c DefaultVal if T does not embed any compile-time value (e.g., T==int). + * + * \sa fix(int), class FixedInt + */ +template class VariableAndFixedInt +{ +public: + static const int value = N; + operator int() const { return m_value; } + VariableAndFixedInt(int val) { m_value = val; } +protected: + int m_value; +}; + +template struct get_fixed_value { + static const int value = Default; +}; + +template struct get_fixed_value,Default> { + static const int value = N; +}; + +#if !EIGEN_HAS_CXX14 +template struct get_fixed_value (*)(),Default> { + static const int value = N; +}; +#endif + +template struct get_fixed_value,Default> { + static const int value = N ; +}; + +template +struct get_fixed_value,Default> { + static const int value = N; +}; + +template EIGEN_DEVICE_FUNC Index get_runtime_value(const T &x) { return x; } +#if !EIGEN_HAS_CXX14 +template EIGEN_DEVICE_FUNC Index get_runtime_value(FixedInt (*)()) { return N; } +#endif + +// Cleanup integer/FixedInt/VariableAndFixedInt/etc types: + +// By default, no cleanup: +template struct cleanup_index_type { typedef T type; }; + +// Convert any integral type (e.g., short, int, unsigned int, etc.) to Eigen::Index +template struct cleanup_index_type::value>::type> { typedef Index type; }; + +#if !EIGEN_HAS_CXX14 +// In c++98/c++11, fix is a pointer to function that we better cleanup to a true FixedInt: +template struct cleanup_index_type (*)(), DynamicKey> { typedef FixedInt type; }; +#endif + +// If VariableAndFixedInt does not match DynamicKey, then we turn it to a pure compile-time value: +template struct cleanup_index_type, DynamicKey> { typedef FixedInt type; }; +// If VariableAndFixedInt matches DynamicKey, then we turn it to a pure runtime-value (aka Index): +template struct cleanup_index_type, DynamicKey> { typedef Index type; }; + +#if EIGEN_HAS_CXX11 +template struct cleanup_index_type, DynamicKey> { typedef FixedInt type; }; +#endif + +} // end namespace internal + +#ifndef EIGEN_PARSED_BY_DOXYGEN + +#if EIGEN_HAS_CXX14 +template +static const internal::FixedInt fix{}; +#else +template +inline internal::FixedInt fix() { return internal::FixedInt(); } + +// The generic typename T is mandatory. Otherwise, a code like fix could refer to either the function above or this next overload. +// This way a code like fix can only refer to the previous function. +template +inline internal::VariableAndFixedInt fix(T val) { return internal::VariableAndFixedInt(val); } +#endif + +#else // EIGEN_PARSED_BY_DOXYGEN + +/** \var fix() + * \ingroup Core_Module + * + * This \em identifier permits to construct an object embedding a compile-time integer \c N. + * + * \tparam N the compile-time integer value + * + * It is typically used in conjunction with the Eigen::seq and Eigen::seqN functions to pass compile-time values to them: + * \code + * seqN(10,fix<4>,fix<-3>) // <=> [10 7 4 1] + * \endcode + * + * See also the function fix(int) to pass both a compile-time and runtime value. + * + * In c++14, it is implemented as: + * \code + * template static const internal::FixedInt fix{}; + * \endcode + * where internal::FixedInt is an internal template class similar to + * \c std::integral_constant + * Here, \c fix is thus an object of type \c internal::FixedInt. + * + * In c++98/11, it is implemented as a function: + * \code + * template inline internal::FixedInt fix(); + * \endcode + * Here internal::FixedInt is thus a pointer to function. + * + * If for some reason you want a true object in c++98 then you can write: \code fix() \endcode which is also valid in c++14. + * + * \sa fix(int), seq, seqN + */ +template +static const auto fix(); + +/** \fn fix(int) + * \ingroup Core_Module + * + * This function returns an object embedding both a compile-time integer \c N, and a fallback runtime value \a val. + * + * \tparam N the compile-time integer value + * \param val the fallback runtime integer value + * + * This function is a more general version of the \ref fix identifier/function that can be used in template code + * where the compile-time value could turn out to actually mean "undefined at compile-time". For positive integers + * such as a size or a dimension, this case is identified by Eigen::Dynamic, whereas runtime signed integers + * (e.g., an increment/stride) are identified as Eigen::DynamicIndex. In such a case, the runtime value \a val + * will be used as a fallback. + * + * A typical use case would be: + * \code + * template void foo(const MatrixBase &mat) { + * const int N = Derived::RowsAtCompileTime==Dynamic ? Dynamic : Derived::RowsAtCompileTime/2; + * const int n = mat.rows()/2; + * ... mat( seqN(0,fix(n) ) ...; + * } + * \endcode + * In this example, the function Eigen::seqN knows that the second argument is expected to be a size. + * If the passed compile-time value N equals Eigen::Dynamic, then the proxy object returned by fix will be dissmissed, and converted to an Eigen::Index of value \c n. + * Otherwise, the runtime-value \c n will be dissmissed, and the returned ArithmeticSequence will be of the exact same type as seqN(0,fix) . + * + * \sa fix, seqN, class ArithmeticSequence + */ +template +static const auto fix(int val); + +#endif // EIGEN_PARSED_BY_DOXYGEN + +} // end namespace Eigen + +#endif // EIGEN_INTEGRAL_CONSTANT_H -- cgit v1.2.3