RT and RT+1 the instruction is not useful when Vectorised because
the output will be overwritten on the next element. To solve this
is easy: define the destination registers as RT and RT+MAXVL
-respectively.
+respectively. This makes it easy for compilers to statically allocate
+registers even when VL changes dynamically.
+
+Bear in mind that both RT and RT+MAXVL are starting points for Vectors,
+and bear in mind that element-width overrides still have to be taken
+into consideration,
* [[isa/svfixedarith]]