Two bugs in one! The count call was duplicating internally the counts for loaded tests (not autosql tests, just loaded). This could manifest itself by executing by file, or by executing a pre statement.
BUG#29803


client/mysqlslap.c:
  1) Declared VOID on pre/post statement return values (we were not using the return value and I prefer to see this declared explicitly)
  2) Removed extra count call which was causing duplication of rows with parsed files examples.
mysql-test/r/mysqlslap.result:
  The additional selects come from fixing the pre return count call. Dropping the final select is a result of fixing the true count.