add weirdmuladd to bitmanip appendix

diff --git a/openpower/sv/bitmanip/appendix.mdwn b/openpower/sv/bitmanip/appendix.mdwn
index cdd3d7dba62240e5c451c444e114e56d00735e48..edf85fea0f9f34acf0aa91061f009d874c0aee0e 100644 (file)
--- a/openpower/sv/bitmanip/appendix.mdwn
+++ b/openpower/sv/bitmanip/appendix.mdwn
@@ -113,3 +113,10 @@ may be morphed to:
         }
 
 ```
+
+Transformation of 4-in, 2-out into a pair of operations:
+
+* 3-in, 2-out `msubx RT, RA, RB, RC` producing {RT,RS} where RS=RT+VL
+* 3-in, 2-out `weirdsubx RT, RA, RB` a hidden RS=RT+VL as input *and output*
+
+<img src="/openpower/sv/weirdmuladd.jpg" width=800 />