Correct vectorisation errors recently introduced

(1) vec_load cannot be used on constants, it can only be used to
access array elements. Replacing UseVectors by False is just a band
aid. vec_load was attached to a routine defining and setting a
variable; really, it should be attached to a routine accessing array
elements, but Kranc doesn't use such an abstraction yet.(2) ToReal is
introduced, but must be removed again for integer expressions such as
the conditions controlling if statements. I added band-aid code to
Conditional[] to remove it. The vectorization routines already handle
IfThen, Pow etc., but Conditional isn't visible to them.

Tools/CodeGen/CalculationFunction.m

@@ -652,7 +652,7 @@ to do this outside all if(){} statements. "declare2" is a list
                {DeclareVariables[localName/@#2, DataType[]],"\n",
                 Conditional[#1,
                   Table[AssignVariableInLoop[localName[var], GridName[var], useVectors], {var, #2}],
-                  Sequence@@If[#3 =!= None, {Table[AssignVariableInLoop[localName[var], #3, useVectors], {var, #2}]}, {}]]},
+                  Sequence@@If[#3 =!= None, {Table[AssignVariableInLoop[localName[var], #3, False (*useVectors*)], {var, #2}]}, {}]]},
                (* else *)
                {}] &,
              {Map[#[[2]]&, conds], varsInConds, Map[#[[3]]&, conds]}], "\n"]}};

Tools/CodeGen/CodeGen.m

@@ -774,12 +774,24 @@
       ]}
      ]]]};
 
+(* Remove call to ToReal from condtion. This should really instead be
+   done much earlier. Sometimes Conditional is called with a
+   conditional that is an expression, sometimes it is a list of
+   strings, so we need to handle both cases. *)
+(* One approach to remove calls to ToReal is to wrap the condition
+  into a function call, such as e.g. Cond[x], which is then handled by
+  the vectorisation code in the same way the IfThen[x,y,z] expression
+  is handled there. *)
+removeToRealFunc[condition_] := Replace[condition, {ToReal[x_] -> x}]
+removeToRealString[condition_] := If[StringQ[condition], StringReplace[condition, "ToReal(" ~~ x__ ~~ ")" :> x], condition]
+removeToReal[condition_] := Map[removeToRealString, removeToRealFunc[condition]]
+
 Conditional[condition_, block_] :=
- {"if (", condition, ")\n",
+ {"if (", removeToReal[condition], ")\n",
   CBlock[block]};
 
 Conditional[condition_, block1_, block2_] :=
- {"if (", condition, ")\n",
+ {"if (", removeToReal[condition], ")\n",
   CBlock[block1], "else\n", CBlock[block2]};
 
 onceInGridLoop[block_] :=