Indexed domain kernel

This MR introduces the possibility to introduce sp.IndexedBase objects in the kernel that form an outer loop for indexing the arrays in the inner loops

pystencils/transformations.py

@@ -398,11 +398,26 @@ def get_base_buffer_index(ast_node, loop_counters=None, loop_iterations=None):
         loop_counters = [loop.loop_counter_symbol for loop in loops]
         loop_iterations = [slice(loop.start, loop.stop, loop.step) for loop in loops]
 
-    actual_sizes = [int_div((s.stop - s.start), s.step)
-                    if s.step != 1 else s.stop - s.start for s in loop_iterations]
+    actual_sizes = list()
+    actual_steps = list()
+    for ctr, s in zip(loop_counters, loop_iterations):
+        if s.step != 1:
+            if (s.stop - s.start) % s.step == 0:
+                actual_sizes.append((s.stop - s.start) // s.step)
+            else:
+                actual_sizes.append(int_div((s.stop - s.start), s.step))
+
+            if (ctr - s.start) % s.step == 0:
+                actual_steps.append((ctr - s.start) // s.step)
+            else:
+                actual_steps.append(int_div((ctr - s.start), s.step))
+        else:
+            actual_sizes.append(s.stop - s.start)
+            actual_steps.append(ctr - s.start)
+
+    print(actual_sizes)
 
-    actual_steps = [int_div((ctr - s.start), s.step)
-                    if s.step != 1 else ctr - s.start for ctr, s in zip(loop_counters, loop_iterations)]
+    print(actual_steps)
 
     field_accesses = ast_node.atoms(Field.Access)
     buffer_accesses = {fa for fa in field_accesses if FieldType.is_buffer(fa.field)}