Vertical First is effectively like an implicit single bit predicate
applied to every SVP64 instruction. **ONLY** one element in each
SVP64 Vector instruction is executed; srcstep and dststep do **not**
-increment, and the Program Counter progresses **immediately* to
+increment, and the Program Counter progresses **immediately** to
the next instruction just as it would for any standard scalar v3.0B
instruction.
Nested looping with different schedules is perfectly possible, as is
calling of functions, however SVSTATE (and any associated SVSTATE) should be stored on the stack.*
+**SUBVL**
+
+Sub-vector elements are not be considered "Vertical". The vec2/3/4
+is to be considered as if the "single element". Caveats exist for
+[[sv/mv.swizzle]] and [[sv/mv.vec]] when Pack/Unpack is enabled.
+
# Pseudocode
// instruction fields: