[Mlir-commits] [mlir] [mlir][ArmSME] Add rudimentary support for tile spills to the stack (PR #76086)

[Benjamin Maxwell]

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@@ -246,16 +259,18 @@ struct AssignTileIDsPattern
     // This case would require allocating a new tile for the result of the
     // scf.if, and moving the contents of %tileA or %tileB to result tile (based
     // on the %some_cond).
+    // Find all the ops that (transitively) depend on this tile.
+    SetVector<Operation *> dependantOps;
+    findDependantOps(tileOp->getResult(0), dependantOps);
     auto tileIDAttr = rewriter.getI32IntegerAttr(*tileId);
-    rewriter.updateRootInPlace(tileOp, [&]() { tileOp.setTileId(tileIDAttr); });
+    rewriter.updateRootInPlace(tileOp, [&] { tileOp.setTileId(tileIDAttr); });
     for (auto *op : dependantOps) {
-      if (auto tileOp = llvm::dyn_cast<ArmSMETileOpInterface>(op)) {
-        auto currentTileId = tileOp.getTileId();
+      if (auto dependantTileOp = llvm::dyn_cast<ArmSMETileOpInterface>(op)) {
+        auto currentTileId = dependantTileOp.getTileId();
         if (currentTileId && unsigned(currentTileId.getInt()) != tileId)
-          return tileOp.emitOpError(
+          return dependantTileOp.emitOpError(
               "already assigned different SME virtual tile!");
-        rewriter.updateRootInPlace(tileOp,
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MacDue wrote:

Because `tileOp` is not the root op here. I renamed it to `dependantTileOp` to make that clearer. 

https://github.com/llvm/llvm-project/pull/76086