**DRAFT**
-The pseudocode for `msubed RT, RA, RB, RC`` is:
-
- prod[0:127] = (RA) * (RB)
- sub[0:127] = EXTZ(RC) - prod
- RT <- sub[64:127]
- RS <- sub[0:63] # RS is either RC or RT+VL
-
-Note that RC is not sign-extended to 64-bit. In a Vector Loop
-it contains the top half of the previous multiply-with-subtract,
-and the current product must be subtracted from it.
-
-
Both `madded` and `msubed` are VA-Form:
|0.....5|6..10|11..15|16..20|21..25|26..31|
to RC extended to SVP64 numbering, including whether RC is set Scalar or
Vector.
+The pseudocode for `msubed RT, RA, RB, RC`` is:
+
+ prod[0:127] = (RA) * (RB)
+ sub[0:127] = EXTZ(RC) - prod
+ RT <- sub[64:127]
+ RS <- sub[0:63] # RS is either RC or RT+VL
+
+Note that RC is not sign-extended to 64-bit. In a Vector Loop
+it contains the top half of the previous multiply-with-subtract,
+and the current product must be subtracted from it.
+
+The pseudocode for `maddx RT, RA, RB, RC` is:
+
+ prod[0:127] = (RA) * (RB)
+ sum[0:127] = EXTZ(RC) + prod
+ RT <- sum[64:127]
+ RS <- sum[0:63] # RS is either RC or RT+VL
+
+Again RC is zero-extended (not shifted), the 128-bit product added
+to it; the lower half of the result stored in RT and the upper half
+in RS.
+
# Appendix
see [[appendix]]