[Mlir-commits] [mlir] [mlir][linalg] Handle unset outer_dims_perm in data layout propagation (PR #98040)

[Quinn Dawkins]

================
@@ -912,10 +906,16 @@ pushDownUnPackOpThroughExpandShape(tensor::UnPackOp unPackOp,
   // new permutation after pushing. This is because moving a source dim is
   // equivalent to moving the associated expanded dims together.
   SmallVector<int64_t> newOuterDimsPerm;
-  for (auto outerPos : outerDimsPerm) {
-    newOuterDimsPerm.insert(newOuterDimsPerm.end(),
-                            reassocIndices[outerPos].begin(),
-                            reassocIndices[outerPos].end());
+  if (!outerDimsPerm.empty()) {
----------------
qedawkins wrote:

This check seems unnecessary because the loop will already do nothing if the permutation is empty. Can we just add the comment in the empty `else` branch to the code that was there before?

https://github.com/llvm/llvm-project/pull/98040