TODO: update
-| ------ | | - | - | - | ------ | ------- |
| RegCAM | | 15 | (14..8) | 7 | (6..5) | (4..0) |
| ------ | | - | - | - | ------ | ------- |
| 0 | | isvec0 | regidx0 | i/f | vew0 | regkey |
| 1 | | isvec1 | regidx1 | i/f | vew1 | regkey |
| .. | | isvec.. | regidx.. | i/f | vew.. | regkey |
| 15 | | isvec15 | regidx15 | i/f | vew15 | regkey |
+| ------ | | - | - | - | ------ | ------- |
i/f is set to "1" to indicate that the redirection/tag entry is to be applied
to integer registers; 0 indicates that it is relevant to floating-point