REMAPed: RA, RB, RC, RT and EA are the canonical (typical) register names
associated with each bit, with RA being the LSB and EA being the MSB.
See table below for ordering. When `SVme` is zero (0b00000) REMAP
- is **fully disabled and inactive**.
+ is **fully disabled and inactive** regardless of the contents of
+ `SVSTATE`, `mi0-mi2/mo0-mo1`, or the four `SVSHAPEn` SPRs
* mi0-mi2/mo0-mo1 - when the corresponding SVme bit is enabled, these
indicate the SVSHAPE (0-3) that the corresponding register (RA etc)
should use, as long as the register's corresponding SVme bit is set
+Programmer's Note: the fact that REMAP is entirely dormant when `SVme` is zero
+allows establishment of REMAP context well in advance, followed by utilising `svremap`
+at a precise (or the very last) moment. Some implementations may exploit this
+to cache (or take some time to prepare caches) in the background whilst other
+(unrelated) instructions are being executed. This is particularly important to
+bear in mind when using `svindex` which will require hardware to perform (and
+cache) additional GPR reads.
+
Programmer's Note: when REMAP is activated it becomes necessary on any
context-switch (Interrupt or Function call) to detect (or know in advance)
that REMAP is enabled and to additionally save/restore the four SVSHAPE