Ranges: scan shuffle naming problem

I have a ludicrous naming problem for a shuffle.

Fundamentally the scan should be done with the following shuffle (0 - is 0 for the operation)

  [a   b      c             d       ]
+ [0   a      b             c       ]
  [a a + b  b + c         c + d     ]
+ [0   0    a + b         b + c     ]
  [a a + b  a + b + c a + b + c + d ]

However this 2nd shuffle (and more for smaller types) is inefficient on avx2

A better option is to compute the scan in both halves, bcast left sum and mix (or zero extend for eve::zero)

  [a   b      c             d       ]
+ [0   a      0             c       ]  // _mm256_alignr_epi8
  [a a + b    c           c + d     ]
+ [0   0    a + b         a + b     ]  // extract + bcast + extend
  [a a + b  a + b + c a + b + c + d ]

The problem is:

The first case shuffle should be called slide_right(a, b, n) or shift_right(a, b, n) However how to call the second ones I'm completely blank. Alternative to having a proper named shuffles in avx case is to do intrinsics in place. But that seems a touch icky.