std::experimental::vector_aligned_tag, std::experimental::vector_aligned
From cppreference.com
                    
                                        
                    < cpp | experimental | simd
                    
                                                            
                    | Defined in header  <experimental/simd> | ||
| struct vector_aligned_tag {}; inline constexpr vector_aligned_tag vector_aligned{}; | ||
This tag type indicates that the buffer of copy_from and copy_to is aligned to memory_alignment_v<T, U>, where the copy operation operates on the simd/simd_mask type T, and the buffer with element type U.
Notes
This tag type allows to implement vector-aligned load and store.