ceph/src/boost/boost/math/tools/is_constant_evaluated.hpp

   1 //  Copyright John Maddock 2011-2021.
   2 //  Use, modification and distribution are subject to the
   3 //  Boost Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_MATH_TOOLS_IS_CONSTANT_EVALUATED_HPP
   7 #define BOOST_MATH_TOOLS_IS_CONSTANT_EVALUATED_HPP
   8
   9 #include <boost/math/tools/config.hpp>
  10
  11 #ifdef __has_include
  12 # if __has_include(<version>)
  13 #  include <version>
  14 #  ifdef __cpp_lib_is_constant_evaluated
  15 #   include <type_traits>
  16 #   define BOOST_MATH_HAS_IS_CONSTANT_EVALUATED
  17 #  endif
  18 # endif
  19 #endif
  20
  21 #ifdef __has_builtin
  22 #  if __has_builtin(__builtin_is_constant_evaluated) && !defined(BOOST_NO_CXX14_CONSTEXPR) && !defined(BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX)
  23 #    define BOOST_MATH_HAS_BUILTIN_IS_CONSTANT_EVALUATED
  24 #  endif
  25 #endif
  26 //
  27 // MSVC also supports __builtin_is_constant_evaluated if it's recent enough:
  28 //
  29 #if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 192528326)
  30 #  define BOOST_MATH_HAS_BUILTIN_IS_CONSTANT_EVALUATED
  31 #endif
  32 //
  33 // As does GCC-9:
  34 //
  35 #if !defined(BOOST_NO_CXX14_CONSTEXPR) && (__GNUC__ >= 9) && !defined(BOOST_MATH_HAS_BUILTIN_IS_CONSTANT_EVALUATED)
  36 #  define BOOST_MATH_HAS_BUILTIN_IS_CONSTANT_EVALUATED
  37 #endif
  38
  39 #if defined(BOOST_MATH_HAS_IS_CONSTANT_EVALUATED) && !defined(BOOST_NO_CXX14_CONSTEXPR)
  40 #  define BOOST_MATH_IS_CONSTANT_EVALUATED(x) std::is_constant_evaluated()
  41 #elif defined(BOOST_MATH_HAS_BUILTIN_IS_CONSTANT_EVALUATED)
  42 #  define BOOST_MATH_IS_CONSTANT_EVALUATED(x) __builtin_is_constant_evaluated()
  43 #elif !defined(BOOST_NO_CXX14_CONSTEXPR) && (__GNUC__ >= 6)
  44 #  define BOOST_MATH_IS_CONSTANT_EVALUATED(x) __builtin_constant_p(x)
  45 #  define BOOST_MATH_USING_BUILTIN_CONSTANT_P
  46 #else
  47 #  define BOOST_MATH_IS_CONSTANT_EVALUATED(x) false
  48 #  define BOOST_MATH_NO_CONSTEXPR_DETECTION
  49 #endif
  50
  51 #endif // BOOST_MATH_TOOLS_IS_CONSTANT_EVALUATED_HPP