compiler: fix operator arg processing and subsampling size

devito/operator/operator.py

@@ -603,11 +603,6 @@ def _prepare_arguments(self, autotune=None, estimate_memory=False, **kwargs):
                  if i.is_Derived and i.parent in nodes]
         toposort = DAG(nodes, edges).topological_sort()
 
-        futures = {}
-        for d in reversed(toposort):
-            if set(d._arg_names).intersection(kwargs):
-                futures.update(d._arg_values(self._dspace[d], args={}, **kwargs))
-
         # Prepare to process data-carriers
         args = kwargs['args'] = ReducerMap()
 
@@ -637,15 +632,12 @@ def _prepare_arguments(self, autotune=None, estimate_memory=False, **kwargs):
             for k, v in p._arg_values(estimate_memory=estimate_memory, **kwargs).items():
                 if k not in args:
                     args[k] = v
-                elif k in futures:
-                    # An explicit override is later going to set `args[k]`
-                    pass
                 elif k in kwargs:
                     # User is in control
                     # E.g., given a ConditionalDimension `t_sub` with factor `fact`
                     # and a TimeFunction `usave(t_sub, x, y)`, an override for
                     # `fact` is supplied w/o overriding `usave`; that's legal
-                    pass
+                    args[k] = args.unique(k, candidate=v)
                 elif is_integer(args[k]) and not contains_val(args[k], v):
                     raise InvalidArgument(
                         f"Default `{p}` is incompatible with other args as "

devito/tools/data_structures.py

@@ -139,7 +139,7 @@ def update(self, values):
         else:
             self.extend(values)
 
-    def unique(self, key):
+    def unique(self, key, candidate=None):
         """
         Returns a unique value for a given key, if such a value
         exists, and raises a ``ValueError`` if it does not.
@@ -150,7 +150,7 @@ def unique(self, key):
             Key for which to retrieve a unique value.
         """
         candidates = self.getall(key)
-        candidates = [c for c in candidates if c is not None]
+        candidates = [c for c in candidates + [candidate] if c is not None]
         if not candidates:
             return None
 

devito/types/dimension.py

@@ -1041,7 +1041,8 @@ def _arg_defaults(self, _min=None, size=None, alias=None):
                     raise ValueError(f"Incompatible size for ConditionalDimension "
                                      f"{self.name}: {size} < {size0}")
             else:
-                defaults[dim.parent.max_name] = range(d0, d0 + factor*size - 1)
+                # Given a factor the last time index is factor*(size - 1)
+                defaults[dim.parent.max_name] = range(d0, d0 + factor*(size - 1) + 1)
 
         return defaults
 

tests/test_operator.py

@@ -1315,6 +1315,34 @@ def test_loose_kwargs(self):
         # But the following should work perfectly fine
         op.arguments(x_size=2, y_size=2)
 
+    @pytest.mark.parametrize('vfact', [1, 3, 4])
+    def test_apply_args_consitency(self, vfact):
+        nt = 201
+        grid = Grid(shape=(11, 11, 11))
+        time = grid.time_dim
+
+        u = TimeFunction(name='u', grid=grid, time_order=2, space_order=4)
+        rec = SparseTimeFunction(name='rec', grid=grid, npoint=1, nt=nt)
+
+        factor = Constant(name='factor', value=vfact, dtype=np.int32)
+        time_sub = ConditionalDimension(name='t_sub', parent=time, factor=factor)
+        usave = TimeFunction(name='usave', grid=grid, space_order=4, time_order=0,
+                             save=nt, time_dim=time_sub)
+
+        eqns = [
+            Eq(u.forward, u + 1),
+            Eq(usave, u),
+        ] + rec.interpolate(expr=u)
+
+        op = Operator(eqns, opt='noop')
+        args0 = op.arguments(time_m=0, time_M=nt-2)
+        args1 = op.arguments(time_m=0, time_M=nt-2, rec=rec, usave=usave)
+
+        for k, v in args0.items():
+            assert k in args1
+            if isinstance(v, int):
+                assert args1[k] == v
+
 
 @skipif('device')
 class TestDeclarator: