Keep attribute when bufferizing scf.forall op (#91236)

Author: srcarroll

mlir/lib/Dialect/SCF/Transforms/BufferizableOpInterfaceImpl.cpp

@@ -1267,6 +1267,9 @@ struct ForallOpInterface
         forallOp.getMixedUpperBound(), forallOp.getMixedStep(),
         /*outputs=*/ValueRange(), forallOp.getMapping());
 
+    // Keep discardable attributes from the original op.
+    newForallOp->setDiscardableAttrs(op->getDiscardableAttrDictionary());
+
     rewriter.eraseOp(newForallOp.getBody()->getTerminator());
 
     // Move over block contents of the old op.

mlir/test/Dialect/SCF/one-shot-bufferize.mlir

@@ -499,7 +499,8 @@ func.func @parallel_insert_slice_no_conflict(
         tensor.parallel_insert_slice %8 into %o[5] [%idx] [%c1] :
           tensor<?xf32> into tensor<?xf32>
       }
-  }
+  } {keep_this_attribute}
+  // CHECK: keep_this_attribute
 
   // CHECK: %[[load:.*]] = memref.load %[[arg2]]
   %f = tensor.extract %2[%c0] : tensor<?xf32>