std::experimental::simd_abi::fixed_size - cppreference.com

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template< int N > struct fixed_size {};

(parallelism TS v2)

The simd_abi::fixed_size<N> tag type ensures data-parallel types to store and manipulate N elements (i.e. simd<T, simd_abi::fixed_size<N>>::size() returns N). An implementation shall support at least all N[132]. Additionally, for every supported simd<T, Abi>, where Abi is an implementation-defined ABI tag, N = simd<T, Abi>::size() shall be supported.

Notes

An implementation may choose to forego ABI compatibility between differently compiled translation units for simd and simd_mask instantiations using the same simd_abi::fixed_size<N> tag. Otherwise, the efficiency of simd<T, Abi> is likely to be better than simd<T, fixed_size<simd_size_v<T, Abi>>> (with Abi not an instance of simd_abi::fixed_size).

Example

See also

the maximum number of elements guaranteed to be supported by fixed
(constant) [edit]
tag type for storing a single element
(typedef) [edit]
tag type that ensures ABI compatibility
(alias template)[edit]
tag type that is most efficient
(alias template)[edit]
obtains an ABI type for given element type and number of elements
(class template) [edit]