std::experimental::simd_abi::deduce

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Extensions for parallelism v2

Parallel exceptions

exception_list

Additional execution policies

execution::vector_policy

execution::unsequenced_policy

Algorithms

induction
reductionreduction_plusreduction_minusreduction_multiplies

reduction_bit_andreduction_bit_orreduction_bit_xorreduction_minreduction_max

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execution::ordered_update_t

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Data-parallel vectors

simd_abi::scalar
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simd_abi::native
simd_abi::compatible

simd_abi::max_fixed_size
simd_abi::deduce

Alignment tags

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overaligned_tagoveraligned

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Defined in header`<experimental/simd>`
template<class T,std::size_t N,class ...Abis> struct deduce;		(parallelism TS v2)

The typededuce<T, N, Abis...>::type is present if and only if:

T is a vectorizable type,
simd_abi::fixed_size<N> is supported, and
every type inAbis... is an ABI tag.

LetDA denotededuce<T, N, Abis...>::type when it presents, then

simd_size_v<T, DA>== N,
simd<T, DA> is default constructible, i.e. it is supported,
DA issimd_abi::scalar ifN==1, otherwise it is implementation-defined.

[edit]Member types

Name	Definition
`type`	an ABI tag type suitable for specified element type`T` and size`N`

[edit]Helper types

template<class T,std::size_t N,class ...Abis> using deduce_t=typename deduce<T, N, Abis...>::type;		(parallelism TS v2)

[edit]Notes

simd_abi::deduce is SFINAE-friendly.

The ABI tag deduced via this facility is a Quality-of-Implementation feature. Implementations can base the choice onAbis..., but can also ignore theAbis... arguments. A simple implementation might simply returnfixed_size<N> unconditionally. An optimized implementation might return an implementation-defined extended ABI tag for most inputs. Consequently, if you need an ABI tag for a certain number of elements, usefixed_size if ABI stability is of concern, and preferdeduce_t otherwise.

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

scalar (parallelism TS v2)	tag type for storing a single element (typedef)[edit]
fixed_size (parallelism TS v2)	tag type for storing specified number of elements (alias template)[edit]
compatible (parallelism TS v2)	tag type that ensures ABI compatibility (alias template)[edit]
native (parallelism TS v2)	tag type that is most efficient (alias template)[edit]