register operands, a full version of this instruction would
be an eye-popping 8 64-bit operands: 4-in, 4-out. As part of a Scalar
ISA this not practical. A compromise is to cut the registers required
-by half.
+by half, placing it on-par with `lq`, `stq` and Indexed
+Load-with-update instructions.
When part of the Scalar Power ISA (not SVP64 Vectorised)
mv.swiz and fmv.swiz operate on four 32-bit
quantities, reducing this instruction to a feasible