[mlir][linalg][transform] PackGreedilyOp/TileToForallOp: Store payload ops in SmallVector

[springerm]

Summary

The TrackingListener removes ops from the internal transform dialect state when they are erased. At the same time, the apply interface method is iterating over all payload ops. Elements may not be removed from the state while iterating over the state.

[springerm]

update

mlir/lib/Dialect/Linalg/TransformOps/LinalgTransformOps.cpp

packMatmulGreedily(RewriterBase &rewriter, LinalgOp linalgOp,
   // `containsMostMinorMatmul(packingRes->packedLinalgOp)` is true, since we
   // also allow degenerate matmul cases (i.e. matvec, dot).
   return linalg::pack(rewriter, genericOp, adjustedPackedSizes);
 }
 
 DiagnosedSilenceableFailure
 PackGreedilyOp::apply(transform::TransformResults &transformResults,
                       transform::TransformState &state) {
-  ArrayRef<Operation *> targetOps = state.getPayloadOps(getTarget());
+  ArrayRef<Operation *> targetOpsView = state.getPayloadOps(getTarget());
+  // Store payload ops into a separate SmallVector because the TrackingListener
+  // removes erased ops from the transform state.
+  SmallVector<Operation *> targetOps(targetOpsView.begin(),
+                                     targetOpsView.end());
 
   SmallVector<Operation *> results;
   TrackingListener listener(state, *this);
   IRRewriter rewriter(getContext(), &listener);
   for (Operation *op : targetOps) {
     auto linalgOp = dyn_cast<LinalgOp>(op);
     if (!linalgOp)
       continue;

 }
 
 DiagnosedSilenceableFailure
 transform::TileToForallOp::apply(transform::TransformResults &transformResults,
                                  transform::TransformState &state) {
   TrackingListener listener(state, *this);
   IRRewriter rewriter(getContext(), &listener);
   auto transformOp = cast<TransformOpInterface>(getOperation());
-  ArrayRef<Operation *> targets = state.getPayloadOps(getTarget());
+  ArrayRef<Operation *> targetsView = state.getPayloadOps(getTarget());
+  // Store payload ops into a separate SmallVector because the TrackingListener
+  // removes erased ops from the transform state.
+  SmallVector<Operation *> targets(targetsView.begin(), targetsView.end());
 
   // Result payload ops.
   SmallVector<Operation *> tileOps;
   SmallVector<Operation *> tiledOps;
 
   // Unpack handles.
   SmallVector<OpFoldResult> mixedNumThreads;
   DiagnosedSilenceableFailure status =