mention SIMD pospopcount really hard to comprehend

diff --git a/openpower/sv/cookbook/pospopcnt.mdwn b/openpower/sv/cookbook/pospopcnt.mdwn
index 3a584ba56a28fa5006d19b9600438cccce105b4b..04e9e1268c6ea26793d3b9b2c3a3f60475a8f128 100644 (file)
--- a/openpower/sv/cookbook/pospopcnt.mdwn
+++ b/openpower/sv/cookbook/pospopcnt.mdwn
@@ -17,7 +17,8 @@ This project is funded through the [NGI Assure Fund](https://nlnet.nl/assure), a
 **Introduction**
 
 Positional popcount in optimised assembler is typically done on SIMD
-ISAs in around 500 lines.  Power ISA thanks to `bpermd` can be much
+ISAs in around 500 lines.  The implementations are extraordinarily
+complex and very hard to understand. Power ISA thanks to `bpermd` can be much
 more efficient: with SVP64 even more so.  The reference implementation
 showing the concept is below.