(no commit message)

diff --git a/openpower/sv/biginteger.mdwn b/openpower/sv/biginteger.mdwn
index 46a421a95e5792b2c35b1a750842862a35d9c123..8ff2396d9fc5d3d69d8937b56e029c5702d854b1 100644 (file)
--- a/openpower/sv/biginteger.mdwn
+++ b/openpower/sv/biginteger.mdwn
@@ -63,8 +63,12 @@ is Z23-Form in "overwrite" on RT.
 Both instructions take two 64-bit sources, concatenate
 them together then extract 64 bits from it, the offset
 location determined by a third source.  So as to avoid
-costly 4-reg (VA-Form) a 2-bit mode `sm` gives four
-potential overwrite and zero-source options instead.
+costly 4-reg (VA-Form) and to allow Vectorised versions
+to use EXTRA3 a 2-bit mode `sm` gives four
+potential overwrite and zero-source options instead
+(a 4-reg VA-Form Vector variant would use EXTRA2,
+limiting the vector offset range and preventing its
+use in biginteger vector-shift operations).
 
 # maddedu