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xdslproject · Nov 7, 2024 · 587a69f · 587a69f
1 parent 3fbfe0b
commit 587a69f
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/xdsl/transforms/csl_stencil_bufferize.py b/xdsl/transforms/csl_stencil_bufferize.py
@@ -415,9 +415,11 @@ def match_and_rewrite(self, op: csl_stencil.ApplyOp, rewriter: PatternRewriter,
                 arg.type, len(op.done_exchange.block.args)
             )
             arg_to_tensor = to_tensor_op(arg, writable=True)
+
+            # set offset going from a buf with ghost cells to one without, assuming symmetric ghost cells on all sides
             symmetric_offsets = tuple(
-                (s - d) // 2
-                for s, d in zip(
+                (src - dst) // 2  # symmetric offset
+                for src, dst in zip(
                     arg_t.get_shape(), yld_arg.type.get_shape(), strict=True
                 )
             )