Use SmallPtrSet instead of std::set to make lit test loop-invariant-masks.mlir deterministic (#4323)

Signed-off-by: Anatoly Myachev <[email protected]>

Author: anmyachev

third_party/intel/lib/Dialect/Triton/Transforms/RemoveMasks.cpp

@@ -444,7 +444,7 @@ class LoopVersioner {
            "Expecting a non-empty collection of masked operations");
 
     // Collect the (loop invariant) mask conditions.
-    std::set<Operation *> maskConds;
+    SmallPtrSet<Operation *, 8> maskConds;
     for (Operation *maskedOp : collector.getMaskedOps()) {
       if (auto loadOp = dyn_cast<tt::LoadOp>(maskedOp))
         maskConds.insert(loadOp.getMask().getDefiningOp());