C++: What is std::simd_width and SIMD concepts (parallelism TS)?

1#include <experimental/simd>
2namespace stdx = std::experimental;
3
4// SIMD width
5std::cout << stdx::simd<float>::size();  // Hardware-dependent
6
7// Fixed width
8stdx::simd<float, stdx::fixed_size<4>> v4;  // Always 4 elements
9
10// Masked operations
11stdx::simd<int> a({1, 2, 3, 4});
12stdx::simd<int> b({5, 6, 7, 8});
13stdx::simd_mask<int> mask = a > 2;
14auto result = stdx::where(mask, a + b, a);
15
16// Reductions
17float sum = stdx::reduce(v);  // Sum
18float max = stdx::hmax(v);    // Horizontal max
19float min = stdx::hmin(v);    // Horizontal min
20
21// Math functions
22auto sin_vals = stdx::sin(v);  // Vectorized sin
23auto sqrt_vals = stdx::sqrt(v);  // Vectorized sqrt
24
25// Memory operations
26stdx::simd<int> data;
27data.copy_to(ptr);  // Aligned store
28data.copy_from(ptr);  // Aligned load
29
30// Blend (conditional select)
31auto blended = stdx::blend(mask, a, b);