[Mlir-commits] [mlir] [mlir][linalg] Hoist masked vector transfer pairs (PR #221481)

[Andrzej Warzyński]

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@@ -233,13 +238,25 @@ void mlir::linalg::hoistRedundantVectorTransfers(Operation *root,
                         << "\n");
 
       SetVector<Operation *> forwardSlice;
-      getForwardSlice(transferRead.getOperation(), &forwardSlice);
+      getForwardSlice(readUnit, &forwardSlice);
+      // A forward slice does not follow a value out of a `vector.mask` region,
+      // so re-slice from each enclosing mask op to reach the write.
+      for (unsigned i = 0; i < forwardSlice.size(); ++i) {
+        auto mask = forwardSlice[i]->getParentOfType<vector::MaskOp>();
+        if (mask && forwardSlice.insert(mask.getOperation()))
+          getForwardSlice(mask.getOperation(), &forwardSlice);
+      }
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banach-space wrote:

I don't follow this part - which test case exercises this?

Basically, since `readUnit` is already either `vector.transfer_read` (unmaked case) or `vector.mask` (masked case), why do we need to care about other MaskOps?

https://github.com/llvm/llvm-project/pull/221481