The designated SPR sandbox consists of non-privileged SPRs
704-719 and privileged SPRs 720-735.
-There are five SPRs, available in any privilege level:
+There are eight SPRs, available in any privilege level:
* SVSTATE (containing copies of MVL, VL and SUBVL as well as context information)
* SVSRR0 which is used for exceptions and traps to store SVSTATE.
* SVSHAPE0-3 for REMAP purposes, re-shaping Vector loops
* SVREMAP for applying specific shapes to specific registers
+If SVSTATE is all zeros then SV is disabled and the contents of the
+other SPRs SVSHAPE/SVREMAP are ignored.
+
For Privilege Levels (trap handling) there are the following SPRs,
where x may be u, s or h for User, Supervisor or Hypervisor
Modes respectively:
# SVSTATE
-This is a standard SPR that contains sufficient information for a
+This is a standard SPR that (REMAP aside) contains sufficient information for a
full context save/restore (see SVSRR0). It contains (and permits setting of):
* MVL (the Maximum Vector Length) - declares (statically) how