utility for symbol safe replacement

src/gt4py/next/program_processors/runners/dace/gtir_builtin_translators.py

@@ -121,7 +121,9 @@ def map_to_parent_sdfg(
                 lambda m: dace.sdfg.replace_properties_dict(outer_desc, m),
             )
             # Same applies to the symbols used as field origin (the domain range start)
-            outer_origin = [val.subs(symbol_mapping) for val in self.origin]
+            outer_origin = [
+                gtx_dace_utils.safe_replace_symbolic(val, symbol_mapping) for val in self.origin
+            ]
 
         outer_node = outer_sdfg_state.add_access(outer)
         return FieldopData(outer_node, self.gt_type, tuple(outer_origin))

src/gt4py/next/program_processors/runners/dace/utils.py

@@ -9,7 +9,7 @@
 from __future__ import annotations
 
 import re
-from typing import Final, Literal
+from typing import Final, Literal, Mapping, Union
 
 import dace
 
@@ -100,3 +100,26 @@ def filter_connectivity_types(
         for offset, conn in offset_provider_type.items()
         if isinstance(conn, gtx_common.NeighborConnectivityType)
     }
+
+
+def safe_replace_symbolic(
+    val: dace.symbolic.SymbolicType,
+    symbol_mapping: Mapping[
+        Union[dace.symbolic.SymbolicType, str], Union[dace.symbolic.SymbolicType, str]
+    ],
+) -> dace.symbolic.SymbolicType:
+    """
+    Replace free symbols in a dace symbolic expression, using `safe_replace()`
+    in order to avoid clashes in case the new symbol value is also a free symbol
+    in the original exoression.
+
+    Args:
+        val: The symbolic expression where to apply the replacement.
+        symbol_mapping: The mapping table for symbol replacement.
+
+    Returns:
+        A new symbolic expression as result of symbol replacement.
+    """
+    x = [val]
+    dace.symbolic.safe_replace(symbol_mapping, lambda m, xx=x: xx.append(xx[-1].subs(m)))
+    return x[-1]

tests/next_tests/unit_tests/program_processor_tests/runners_tests/dace_tests/test_dace_utils.py

@@ -0,0 +1,22 @@
+# GT4Py - GridTools Framework
+#
+# Copyright (c) 2014-2024, ETH Zurich
+# All rights reserved.
+#
+# Please, refer to the LICENSE file in the root directory.
+# SPDX-License-Identifier: BSD-3-Clause
+
+"""Test utility functions of the dace backend module."""
+
+import pytest
+
+from gt4py.next.program_processors.runners.dace import utils as gtx_dace_utils
+
+
+dace = pytest.importorskip("dace")
+
+
+def test_safe_replace_symbolic():
+    assert gtx_dace_utils.safe_replace_symbolic(
+        dace.symbolic.pystr_to_symbolic("x*x + y"), symbol_mapping={"x": "y", "y": "x"}
+    ) == dace.symbolic.pystr_to_symbolic("y*y + x")