std::experimental:: is_simd, std::experimental:: is_simd_mask

From cppreference.com
C++
Experimental
Extensions for parallelism v2
SIMD library
Defined in header <experimental/simd>
template < class T >
struct is_simd ;
(1) (parallelism TS v2)
template < class T >
struct is_simd_mask ;
(2) (parallelism TS v2)
1) If T is a specialization of the simd class template, provides the member constant value equal true . For any other type, value is false .
2) If T is a specialization of the simd_mask class template, provides the member constant value equal true . For any other type, value is false .

Template parameters

T - a type to check

Helper variable template

template < class T >
constexpr bool is_simd_v = is_simd < T > :: value ;
(parallelism TS v2)
template < class T >
constexpr bool is_simd_mask_v = is_simd_mask < T > :: value ;
(parallelism TS v2)

Inherited from std:: integral_constant

Member constants

value
[static]
true if T is a simd / simd_mask type, false otherwise
(public static member constant)

Member functions

operator bool
converts the object to bool , returns value
(public member function)
operator()
(C++14)
returns value
(public member function)

Member types

Type Definition
value_type bool
type std:: integral_constant < bool , value >

Notes

is_simd_v < T > is necessary but not sufficient for testing whether T can be used as a SIMD type. For example, is_simd_v < simd < bool >> is true , even though bool is not included in the permissible vectorizable types. The missing condition is std:: is_constructible_v < T > , which is false for simd < bool > .

Example

Run this code 
#include <experimental/simd>
#include <iostream>
#include <string_view>
 
namespace stdx = std::experimental;
 
template<typename T>
void test_simd(std::string_view type_name)
{
    std::cout << std::boolalpha
              << "Type: " << type_name << '\n'
              << "  is_simd: " << stdx::is_simd_v<T> << '\n'
              << "  is_constructible: " << std::is_constructible_v<T> << '\n';
}
 
template<typename T>
void test_simd_mask(std::string_view type_name)
{
    std::cout << std::boolalpha
              << "Type: " << type_name << '\n'
              << "  is_simd_mask: " << stdx::is_simd_mask_v<T> << '\n'
              << "  is_constructible: " << std::is_constructible_v<T> << "\n\n";
}
 
int main() 
{
    test_simd<int>("int");
    test_simd_mask<int>("int");
 
    test_simd<stdx::simd<float>>("simd<float>");
    test_simd_mask<stdx::simd_mask<float>>("simd_mask<float>");
 
    test_simd<stdx::simd<bool>>("simd<bool>");
    test_simd_mask<stdx::simd_mask<bool>>("simd_mask<bool>");
}

Output: 

Type: int
  is_simd: false
  is_constructible: true
Type: int
  is_simd_mask: false
  is_constructible: true
 
Type: simd<float>
  is_simd: true
  is_constructible: true
Type: simd_mask<float>
  is_simd_mask: true
  is_constructible: true
 
Type: simd<bool>
  is_simd: true
  is_constructible: false
Type: simd_mask<bool>
  is_simd_mask: true
  is_constructible: false
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