std::experimental::simd<T,Abi>::copy_from
From cppreference.com
< cpp | experimental | simd | simd
| template< class U, class Flags > void copy_from( const U* mem, Flags flags ); |
(parallelism TS v2) | |
The load function replaces all elements of a simd such that the ith element is assigned with static_cast<T>(mem[i]) for all i in the range of [0, size()).
Parameters
| mem | - | a pointer into an array where [mem, mem + size()) is a valid range
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| flags | - | if of type vector_aligned_tag, the load constructor may assume mem to point to storage aligned by memory_alignment_v<simd, U> |
| Type requirements | ||
-U must be a vectorizable type.
| ||
-is_simd_flag_type_v<Flags> must be true.
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Example
Run this code
#include <cstddef> #include <experimental/simd> #include <iostream> #include <numeric> namespace stdx = std::experimental; void print(auto const& a) { for (std::size_t i{}; i != std::size(a); ++i) std::cout << a[i] << ' '; std::cout << '\n'; } int main() { alignas(stdx::memory_alignment_v<stdx::native_simd<int>>) std::array<int, stdx::native_simd<int>::size() * 2> mem = {}; std::iota(mem.begin(), mem.end(), 0); print(mem); stdx::native_simd<int> a; // uninitialized a.copy_from(&mem[0], stdx::vector_aligned); print(a); a.copy_from(&mem[1], stdx::element_aligned); // vector_aligned would likely crash print(a); }
Possible output:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 1 2 3 4 5 6 7 1 2 3 4 5 6 7 8
See also
| (parallelism TS v2) |
obtains an appropriate alignment for vector_aligned (class template) |
| (parallelism TS v2) |
stores simd elements to contiguous memory (public member function) |
| (parallelism TS v2) |
constructs a simd object (public member function) |