[Mlir-commits] [mlir] [mlir][Tensor] Retain discardable attrs back in cast(pack) folder (PR #115772)

[Mehdi Amini]

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@@ -4798,6 +4798,7 @@ struct FoldTensorCastPackOp : public OpRewritePattern<PackOp> {
     PackOp newOp = rewriter.create<PackOp>(
         op.getLoc(), newOperands[0], newOperands[1], op.getInnerDimsPos(),
         newMixedTileSizes, op.getPaddingValue(), op.getOuterDimsPerm());
+    newOp->setDiscardableAttrs(op->getDiscardableAttrDictionary());
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joker-eph wrote:

Why is this sounds? How do you guarantee that the pattern can't invalidate anything encoded in there?

We don't have a principled approach to this in general unfortunately, here the pattern replace the op so it was visible, other folders operate in-place and are propagating "by accident".

By the way: can't this pattern just operate in-place here instead?

https://github.com/llvm/llvm-project/pull/115772