[PATCH] D80347: [mlir][Linalg] Add support for fusion between indexed_generic ops and generic ops on tensors.

[Han-Chung Wang via Phabricator via llvm-commits]

hanchung added inline comments.


================
Comment at: mlir/lib/Dialect/Linalg/Transforms/Fusion.cpp:503-511
+      AffineMap consumerResultIndexMap =
+          consumer.getInputIndexingMap(consumerIdx);
+      AffineMap producerResultIndexMap = producer.getOutputIndexingMap(0);
+      AffineMap invProducerResultIndexMap =
+          inversePermutation(producerResultIndexMap);
+      assert(invProducerResultIndexMap &&
+             "expected producer result indexig map to be invertible");
----------------
mravishankar wrote:
> I think this should be outside of the `else`?
Good catch, in the beginning I thought we can't compose the maps sometimes. After review the comment of compose method, I found that the last two maps should swap.

See comments of AffineMap::compose():

```
  /// Example:
  ///   map1: `(d0, d1)[s0, s1] -> (d0 + 1 + s1, d1 - 1 - s0)`
  ///   map2: `(d0)[s0] -> (d0 + s0, d0 - s0)`
  ///   map1.compose(map2):
  ///     `(d0)[s0, s1, s2] -> (d0 + s1 + s2 + 1, d0 - s0 - s2 - 1)`
```

Add some comment for it.


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https://reviews.llvm.org/D80347