Function safe_arch::blend_varying_m256d

#[must_use]pub fn blend_varying_m256d(a: m256d, b: m256d, mask: m256d) -> m256d

This is supported with target feature avx only.

Blend the lanes according to a runtime varying mask.

The sign bit of each lane in the mask value determines if the output lane uses a (mask non-negative) or b (mask negative).

let a = m256d::from_array([0.0, 1.0, 20.0, 30.0]);
let b = m256d::from_array([2.0, 3.0, 70.0, 80.0]);
let mask = m256d::from_array([-1.0, 0.0, 0.0, -1.0]);
let c = blend_varying_m256d(a, b, mask).to_array();
assert_eq!(c, [2.0, 1.0, 20.0, 80.0]);