Remove duplicate kernel tag and clean up mass programs

grudge/op.py

@@ -77,15 +77,11 @@ from meshmode.dof_array import freeze, flatten, unflatten
 from grudge.symbolic.primitives import TracePair
 
 
-# {{{ tags
+# {{{ Kernel tags
 
 class HasElementwiseMatvecTag(FirstAxisIsElementsTag):
     pass
 
-
-class MassOperatorTag(HasElementwiseMatvecTag):
-    pass
-
 # }}}
 
 
@@ -545,16 +541,16 @@ def _apply_mass_operator(dcoll, dd_out, dd_in, vec):
     return DOFArray(
         actx,
         tuple(
-            actx.einsum("ej,ij,ej->ei",
-                        ae_i,
+            actx.einsum("ij,ej,ej->ei",
                         reference_mass_matrix(
                             actx,
                             out_element_group=out_grp,
                             in_element_group=in_grp
                         ),
+                        ae_i,
                         vec_i,
-                        arg_names=("jac", "mass_mat", "vec"),
-                        tagged=(MassOperatorTag(),))
+                        arg_names=("mass_mat", "jac", "vec"),
+                        tagged=(HasElementwiseMatvecTag(),))
 
             for in_grp, out_grp, ae_i, vec_i in zip(
                     in_discr.groups, out_discr.groups, area_elements, vec)
@@ -633,22 +629,22 @@ def _apply_inverse_mass_operator(dcoll, dd_out, dd_in, vec):
                 # true_Minv ~ ref_Minv * ref_M * (1/jac_det) * ref_Minv
                 actx.einsum("ik,km,em,mj,ej->ei",
                             ref_mass_inv, ref_mass, jac_inv, ref_mass_inv, x,
-                            tagged=(MassOperatorTag(),))
+                            tagged=(HasElementwiseMatvecTag(),))
             )
         return DOFArray(actx, data=tuple(data))
     else:
         return DOFArray(
             actx,
             tuple(
-                actx.einsum("ej,ij,ej->ei",
-                            iae_i,
+                actx.einsum("ij,ej,ej->ei",
                             reference_inverse_mass_matrix(
                                 actx,
                                 element_group=grp
                             ),
+                            iae_i,
                             vec_i,
-                            arg_names=("jac_det_inv", "mass_inv_mat", "vec"),
-                            tagged=(MassOperatorTag(),))
+                            arg_names=("mass_inv_mat", "jac_det_inv", "vec"),
+                            tagged=(HasElementwiseMatvecTag(),))
 
                 for grp, iae_i, vec_i in zip(discr.groups,
                                              inv_area_elements, vec)