Revert "Pick full packet unconditionally when EIGEN_UNALIGNED_VECTORIZE"

This reverts commit 44df2109c8c700222643a9a45f144676348f4df1

Eigen/src/Core/util/XprHelper.h

diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index 22f8bdd..26aa609 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -194,20 +194,8 @@
   };
 };
 
-// If we vectorize regardless of alignment, always pick the full-sized packet,
-// if we have enough data to process.
-//
-// Otherwise, pick the packet size we know is going to work with the alignment
-// of the given data. See
-// <https://gitlab.com/libeigen/eigen/merge_requests/46#note_270578113> for more
-// information.
-#if EIGEN_UNALIGNED_VECTORIZE
 template<int Size, typename PacketType,
          bool Stop = Size==Dynamic || Size >= unpacket_traits<PacketType>::size || is_same<PacketType,typename unpacket_traits<PacketType>::half>::value>
-#else
-template<int Size, typename PacketType,
-         bool Stop = Size==Dynamic || (Size%unpacket_traits<PacketType>::size)==0 || is_same<PacketType,typename unpacket_traits<PacketType>::half>::value>
-#endif
 struct find_best_packet_helper;
 
 template< int Size, typename PacketType>