Summary of Compliancy Levels, each Level includes all lower levels:
* **Ultra-embedded**: `setvl` instruction and context-switching of SVSTATE
- to/from SVSRR1. Register Files as Standard Power ISA.
+ to/from SVSRR1. Register Files as Standard Power ISA. `scalar identity`
+ implemented.
* **Embedded**: `svstep` instruction,
and support for Hardware for-looping
in both Horizontal-First and Vertical-First Mode as well as Predication
permitted to declare meeting the 3D/Advanced Level unless implementing
*all* REMAP Capabilities.
+**Power ISA Compliancy Levels**
+
+The SV Compliancy Levels have nothing to do with the Power ISA Compliancy
+Levels (SFS, SFFS, Linux, AIX). They are separate and independent. It
+is perfectly fine to implement Ultra-Embedded on AIX, and perfectly fine to implement 3D/Advanced on SFS. **Compliance with SV Levels does not convey or remove the obligation of Compliance with SFS/SFFS/Linux/AIX Levels and vice-versa**.
+
# Ultra-Embedded Level
This level exists as an entry-level into SVP64, most suited to resource
higher priority than execution speed.
This level sets the bare minimum requirements, where everything with the
-exception of the `setvl` instruction may be software-emulated through
+exception of `scalar identity` and
+the `setvl` instruction may be software-emulated through
JIT Translation or Illegal Instruction traps. SVSTATE, as effectively
a Sub-Program-Counter, joins MSR and PC (CIA, NIA)
as direct peers and must be switched on any context-switch (Trap or
* Any SV instructions not implemented
* any unimplemented SV Context SPRs read or written
* all unimplemented uses of the SVP64 Prefix
+* non-scalar-identity SVP64 instructions
Implementors are free and clear to implement any other features of
SVP64 however only by meeting all of the mandatory requirements above
will Compliance with the Ultra-Embedded Level be achieved.
+Note that `scalar identity` is defined as being when the execution of
+an SVP64 Prefixed instruction is identical in every respect to
+Scalar non-prefixed, i.e. as if the Prefix had not been present.
+Additionally all SV SPRs must be zero and the 24-bit `RM` field must be zero.
+
# Embedded Level
This level is more suitable for Hardware implementations where performance and power saving begins to matter. A second instruction, `svstep`, used