Three examples are illustrated of different types of Scalar-Vector
operations. Note that in its simplest form **only one** element is
executed per instruction **not** multiple elements per instruction.
+(The more advanced version of Vertical-First mode may execute multiple
+elements per instruction, however the number executed **must** remain
+a fixed quantity.)
Now that such explicit loops can increment inexorably towards VL,
of course we now need a way to test if srcstep or dststep have reached