29 Numerics library [numerics]

29.10 Data-parallel types [simd]

29.10.4 vec type traits [simd.traits]

template<class T, class U = typename T::value_type> struct alignment { see below };

alignment<T, U> has a member value if and only if

(1.1)
T is a specialization of basic_mask and U is bool, or
(1.2)
T is a specialization of basic_vec and U is a vectorizable type.

If value is present, the type alignment<T, U> is a BinaryTypeTrait with a base characteristic of integral_constant<size_t, N> for some unspecified N ([simd.ctor], [simd.loadstore]).

[Note 1:

value identifies the alignment restrictions on pointers used for (converting) loads and stores for the given type T on arrays of type U.

— end note]

The behavior of a program that adds specializations for alignment is undefined.

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template<class T, class V> struct rebind { using type = see below; };

The member type is present if and only if

(4.1)
V is a data-parallel type,
(4.2)
T is a vectorizable type, and
(4.3)
deduce-abi-t<T, V::size()> has a member type type.

If V is a specialization of basic_vec, let Abi1 denote an ABI tag such that basic_vec<T, Abi1>::size() equals V::size().

If V is a specialization of basic_mask, let Abi1 denote an ABI tag such that basic_mask<sizeof(T), Abi1>::size() equals V::size().

Where present, the member typedef type names basic_vec<T, Abi1> if V is a specialization of basic_vec or basic_mask<sizeof(T), Abi1> if V is a specialization of basic_mask.

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template<simd-size-type N, class V> struct resize { using type = see below; };

Let T denote

(7.1)
typename V::value_type if V is a specialization of basic_vec,
(7.2)
otherwise integer-from<mask-element-size<V>> if V is a specialization of basic_mask.

The member type is present if and only if

(8.1)
V is a data-parallel type, and
(8.2)
deduce-abi-t<T, N> has a member type type.

If V is a specialization of basic_vec, let Abi1 denote an ABI tag such that basic_vec<T, Abi1>::size() equals N.

If V is a specialization of basic_mask, let Abi1 denote an ABI tag such that basic_mask<sizeof(T), Abi1>::size() equals N.

Where present, the member typedef type names basic_vec<T, Abi1> if V is a specialization of basic_vec or basic_mask<sizeof(T), Abi1> if V is a specialization of basic_mask.