`mm` are as per `svindex`.
*Programmer's Note: offsets for `svshape2` may be specified in the range
-0-7. Given that the principle of Simple-V is to fit on top of
+0-15. Given that the principle of Simple-V is to fit on top of
byte-addressable register files and that GPR and FPR are 64-bit (8 bytes)
it should be clear that the offset may, when `elwidth=8`, begin an
element-level operation starting element zero at any arbitrary byte.
-On cursory examination attempting to go **beyond** the range 0-7 seems
-inadequate until it is recalled that the **next GPR or FPR** is an
+On cursory examination attempting to go beyond the range 0-7 seems
+unnecessary given that the **next GPR or FPR** is an
alias for an offset in the range 8-15. Thus by simply increasing
the starting Vector point of the operation to the next register it
can be seen that the offset of 0-7 would be sufficient. Unfortunately
-however some operations are EXTRA2-encoded which does in fact leave
-them inaccessible. TODO: decide if the decision to sacrifice one
-bit of `offs` in favour of an `inv` bit is worth it.
-<https://bugs.libre-soc.org/show_bug.cgi?id=911#c9>*
+however some operations are EXTRA2-encoded it is **not possible**
+to increase the GPR/FPR register number by one, because EXTRA2-encoding
+of GPR/FPR Vector numbers are restricted to even numbering. The
+additional offset range (8-15) helps overcome this limitation.*
# TODO