compiler: update

devito/ir/clusters/cluster.py

@@ -358,15 +358,17 @@ def dspace(self):
         # Dimension-centric view of the data space
         intervals = IntervalGroup.generate('union', *parts.values())
 
-        # 'union' may have resulted in intervals stricter than needed
-        # e.g. issue #2235. We relax the upper interval with the upper
-        # from not mapped parts
+        # 'union' may consume intervals (values) from keys that have dimensions
+        # not mapped to intervals e.g. issue #2235, resulting in reduced
+        # iteration size. Here, we relax this mapped upper interval, by
+        # intersecting intervals with matching only dimensions
         for f, v in parts.items():
-            for d in f.dimensions:
+            for i in v:
                 # oobs check is not required but helps reduce
                 # interval reconstruction
-                if d in oobs and not v[d].is_Null:
-                    intervals = intervals.set_upper(d, v[d].upper)
+                if i.dim in oobs and i.dim in f.dimensions:
+                    ii = intervals[i.dim].intersection(v[i.dim])
+                    intervals = intervals.set_upper(i.dim, ii.upper)
 
         # E.g., `db0 -> time`, but `xi NOT-> x`
         intervals = intervals.promote(lambda d: not d.is_Sub)