add 2D remap idea

diff --git a/simple_v_extension/specification.mdwn b/simple_v_extension/specification.mdwn
index 5e0c1b311253362595fe1932450a6fbdbfe52b70..d523c7e282648b17df0f27f6c3bb0f3162a6e3cf 100644 (file)
--- a/simple_v_extension/specification.mdwn
+++ b/simple_v_extension/specification.mdwn
@@ -814,3 +814,9 @@ for element-grouping, if there is unused space within a register
   they are set to all ones on write and are ignored on read, matching the
   existing standard for storing smaller FP values in larger registers.
 
+## 2D remapping
+
+idea: have an additional set of register CSRs that indicate that, instead of
+a straight 1D linear relationship, the element index is put through
+a (reasonably simple) 2D processing algorithm.  in this way, 4x3 blocks
+of registers can have the ordering changed to 3x4 for example.