In scalar v3.0B traps, exceptions and interrupts, two SRRs are saved/restored:
-* SRR0 to store the PC
+* SRR0 to store the PC (CIA/NIA)
* SRR1 to store a copy of the MSR
Given that SVSTATE is effectively a Sub-PC it is critically important to add saving/restoring of SVSTATE as a full peer equal in status to PC, in every way. At any time PC is saved or restored, so is SVSTATE in **exactly** the same way for **exactly** the same reasons.