Add Packet2l for SSE.

Eigen/src/Core/GenericPacketMath.h

@@ -44,24 +44,30 @@ namespace internal {
 
 struct default_packet_traits {
   enum {
+    // Ops that are implemented for most types.
     HasAdd = 1,
     HasSub = 1,
     HasShift = 1,
     HasMul = 1,
     HasNegate = 1,
     HasAbs = 1,
-    HasArg = 0,
     HasAbs2 = 1,
-    HasAbsDiff = 0,
     HasMin = 1,
     HasMax = 1,
     HasConj = 1,
     HasSetLinear = 1,
     HasSign = 1,
+
+    HasArg = 0,
+    HasAbsDiff = 0,
     HasBlend = 0,
     // This flag is used to indicate whether packet comparison is supported.
     // pcmp_eq, pcmp_lt and pcmp_le should be defined for it to be true.
     HasCmp = 0,
+    HasRound = 0,
+    HasRint = 0,
+    HasFloor = 0,
+    HasCeil = 0,
 
     HasDiv = 0,
     HasReciprocal = 0,
@@ -73,7 +79,6 @@ struct default_packet_traits {
     HasLog1p = 0,
     HasLog10 = 0,
     HasPow = 0,
-
     HasSin = 0,
     HasCos = 0,
     HasTan = 0,
@@ -96,12 +101,7 @@ struct default_packet_traits {
     HasIGammaDerA = 0,
     HasGammaSampleDerAlpha = 0,
     HasIGammac = 0,
-    HasBetaInc = 0,
-
-    HasRound = 0,
-    HasRint = 0,
-    HasFloor = 0,
-    HasCeil = 0
+    HasBetaInc = 0
   };
 };