-# alternative 32-64 encoding
+# alternative 32-64 encoding (1)
```
|0-5| 6-27 28 29|30-31|32|33-35|36-37| 38-59 | 60-63 | Description |
|PO9| rm0 | 0 0 | 0 0 | 0 000 rm1 | xxxx | 0000 | SVP64:EXT900 |
|PO9| rm0 | 0 0 | 0 0 | 1 000 rm1 | xxxx | 0000 | SSingle:EXT900 |
|PO9| xxx | x 0 | 0 0 | x !zero | xxxx | !zero | 55-bit RESERVED |
-|PO9| xxx | x 0 | 0 0 | 32-bit EXT900 (Vectorizable) |
+|PO9| xxx | 0 1 | 0 0 | 32-bit EXT900 (Vectorizable) |
|PO9| xxx | 1 1 | 0 0 | 32-bit EXT901 (Unvectorizable) |
|PO9| !ZERO | 0 0 | 1 | DWi | SSingle:EXT232-263 |
|PO9| 0000 | 0 0 | 1 | DWi | Scalar EXT232-263 |
-|PO9| nnnn | 1 0 | 1 | DWi | SVP64:EXT232-263 |
+|PO9| RM | 1 0 | 1 | DWi | SVP64:EXT232-263 |
|PO9| 0000 | 0 1 | Defined Word-instruction | 32-bit Unvec in 64b|
|PO9| !ZERO | 0 1 | Defined Word-instruction | SSingle:EXT000-063 |
-|PO9| nnnn | 1 1 | Defined Word-instruction | SVP64:EXT000-063 |
+|PO9| RM | 1 1 | Defined Word-instruction | SVP64:EXT000-063 |
```
Fields:
+* RM 24-bit SVP64 prefix
* SVP64 `RM <- rm0 || rm1`
Length detection:
two 32-bit instructions.
* but those types of space-saving instructions
**also need to be Vectorizable*
+
+# alternative 32-64 encoding (2)
+
+the complexity of attempting to fit
+
+
+```
+|0-5| 6-27 28 29|30-31|32|33-35|36-37| 38-59 | 60-63 | Description |
+|---|-----|-----|-----|--|-----|-----|-------|-------|------------------|
+|PO9| rm0 | 0 0 | 0 0 | 0 000 rm1 | xxxx | 0000 | SVP64:EXT900 |
+|PO9| rm0 | 0 0 | 0 0 | 1 000 rm1 | xxxx | 0000 | SSingle:EXT900 |
+|PO9| xxx | x 0 | 0 0 | x !zero | xxxx | !zero | 55-bit RESERVED |
+|PO9| xxx | x 0 | 0 0 | 32-bit EXT900 (Vectorizable) |
+|PO9| xxx | 1 1 | 0 0 | 32-bit EXT901 (Unvectorizable) |
+|PO9| !ZERO | 0 0 | 1 | DWi | SSingle:EXT232-263 |
+|PO9| 0000 | 0 0 | 1 | DWi | Scalar EXT232-263 |
+|PO9| nnnn | 1 0 | 1 | DWi | SVP64:EXT232-263 |
+|PO9| 0000 | 0 1 | Defined Word-instruction | 32-bit Unvec in 64b|
+|PO9| !ZERO | 0 1 | Defined Word-instruction | SSingle:EXT000-063 |
+|PO9| nnnn | 1 1 | Defined Word-instruction | SVP64:EXT000-063 |
+```