How to check which GaussianBlur version is used in OpenCV?

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I built OpenCV using IPP, but I want to be sure that cv::GuassianBlur is executed by using that version and not other implementations.

I'm having this doubt because I've built OpenCV with OpenCL turned on, and I see on the stack call a lot using the libnvidia-opencl, while I never use OpenCL/CUDA/whatever-GPU-stuff in my code.

I'll rebuild OpenCV with -DWITH_OPENCL=OFF, but I want to be sure somehow that I use the IPP implementation. This is because I've installed the latest version of IPP and I can use very performant Intel CPU.