[mlir][vector] Add a check to ensure bailing out when reducing to a scalar, as ExtractStridedSliceOp does not support handling scalars

Author: Prakhar-Dixit

mlir/lib/Dialect/Vector/Transforms/VectorUnroll.cpp

@@ -355,6 +355,11 @@ struct UnrollMultiReductionPattern
 
   LogicalResult matchAndRewrite(vector::MultiDimReductionOp reductionOp,
                                 PatternRewriter &rewriter) const override {
+    auto resultType = reductionOp->getResult(0).getType();
+    if (mlir::isa<mlir::FloatType>(resultType) ||
+        mlir::isa<mlir::IntegerType>(resultType)) {
+      return failure();
+    }
     std::optional<SmallVector<int64_t>> targetShape =
         getTargetShape(options, reductionOp);
     if (!targetShape)