Error in Redundant Array Removal

[philip-paul-mueller]

The new MapFusion transformation removes useless length 1 dimensions that were introduced by the over approximation. One of the big changes is, that now a the dimensionality the two subsets of a memlet are the same (it was not always true before anyway).

If the following patch is used to disable the strict data flow mode in the auto optimizer:

From 213c36d5ba337bfc1541941b0bc459f94270dcf5 Mon Sep 17 00:00:00 2001
From: Philip Mueller <[email protected]>
Date: Fri, 6 Sep 2024 14:54:20 +0200
Subject: [PATCH] Disable strict dataflow in auto optimizer.

---
 dace/transformation/auto/auto_optimize.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/dace/transformation/auto/auto_optimize.py b/dace/transformation/auto/auto_optimize.py
index 09ff481e3..db0ba5ef2 100644
--- a/dace/transformation/auto/auto_optimize.py
+++ b/dace/transformation/auto/auto_optimize.py
@@ -52,6 +52,9 @@ def greedy_fuse(graph_or_subgraph: GraphViewType,
     :param permutations_only: Disallow splitting of maps during MultiExpansion stage
     :param expand_reductions: Expand all reduce nodes before fusion
     """
+    validate_all = True
+    validate = True
+    strict_dataflow = True
     debugprint = config.Config.get_bool('debugprint')
     if isinstance(graph_or_subgraph, ControlFlowRegion):
         if isinstance(graph_or_subgraph, SDFG):
@@ -61,7 +64,7 @@ def greedy_fuse(graph_or_subgraph: GraphViewType,
             #  We have to use `strict_dataflow` because it is known that `CompositeFusion`
             #  has problems otherwise.
             graph_or_subgraph.apply_transformations_repeated(
-                    MapFusion(strict_dataflow=True),
+                    MapFusion(strict_dataflow=strict_dataflow),
                     validate_all=validate_all,
             )
 
@@ -82,7 +85,7 @@ def greedy_fuse(graph_or_subgraph: GraphViewType,
         if isinstance(graph_or_subgraph, SDFGState):
             sdfg = graph_or_subgraph.parent
             sdfg.apply_transformations_repeated(
-                    MapFusion(strict_dataflow=True),
+                    MapFusion(strict_dataflow=strict_dataflow),
                     validate_all=validate_all,
             )
             graph = graph_or_subgraph
-- 
2.46.0

the test tests/npbench/weather_stencils/vadv_test.py will fail with an error that Subset.offset() was called with offsets of different dimensionality.