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

[llvmlistbot at llvm.org]

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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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MaheshRavishankar wrote:

I dont know if it can be inplace. The result type is changing I think. 

I think the working assumption is that preserving these attributes are, at best, best effort. You cant always transfer over attributes, so its safe to discard. But in cases like this when the op is being replaced by an op of the same type, its also safe to carry it over. If someone relies on this attribute thats "at your risk", but best effort to preserve the attribute. Its not the most principled thing, but more a pragmatic thing. 

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