[vector] Sparse load (simple gather) of vector from array?

[Lev Serebryakov]

 I have (long) array of floats: `float[] data`. I have Spicies of
FloatArray, `S`. I need to create `FloatVector` with even elements (0,
2, 4, ...) set to elements from `data` array and odd elements set to
zero (`0.0f`).

  So, if we use 256 bit vectors shape, it should be like this:

{data[offest+0], 0.0f, data[offest+1], 0.0f, data[offest+2], 0.0f,
data[offest+3], 0.0f}

  I could load vector from array and blend it with zero vector, but it
will have wrong float data from array (like `offset+0`, `offset+2`, etc).

 What is simplest way to perform such "gather" load?

-- 
// Black Lion AKA Lev Serebryakov