[Mlir-commits] [mlir] [mlir][linalg] Canonicalize non-identity `linalg.generic` ops (PR #101430)

[Ian Wood]

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@@ -1217,9 +1217,12 @@ struct EraseIdentityLinalgOp : public OpRewritePattern<OpTy> {
 
   LogicalResult matchAndRewrite(OpTy linalgOp,
                                 PatternRewriter &rewriter) const override {
-    // Check all indexing maps are identity.
-    if (llvm::any_of(linalgOp.getIndexingMapsArray(),
-                     [](AffineMap map) { return !map.isIdentity(); }))
+    // All indexing maps must be equal permutations
+    auto indexingMaps = linalgOp.getIndexingMapsArray();
+    if (!llvm::all_equal(indexingMaps))
+      return failure();
+
+    if (!indexingMaps.empty() && !indexingMaps.front().isPermutation())
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IanWood1 wrote:

Good point, I didn't realize that if they are projections then a loop would be undefined. Removed this as it doesn't seem worth keeping. 

https://github.com/llvm/llvm-project/pull/101430