System Information

OpenCV version: 4.7.0
Operating System / Platform: Window 11 x64

Detailed description

Inferring a Unet-mobileone model on BACKEND_OPENCV+TARGET_CPU results in

OpenCV(4.7.0-dev) Error: Assertion failed (fusedAddMat.empty() && (conv_dim == CONV_1D || conv_dim == CONV_2D)) in cv::dnn::runFastConv, file D:\Dev\opencv\modules\dnn\src\layers\fast_convolution\fast_convolution.cpp, line 372
OpenCV(4.7.0-dev) D:\Dev\opencv\modules\dnn\src\layers\fast_convolution\fast_convolution.cpp:372: error: (-215:Assertion failed) fusedAddMat.empty() && (conv_dim == CONV_1D || conv_dim == CONV_2D) in function 'cv::dnn::runFastConv'

Assert fails with fusedAddMat not being empty and conv_dim == CONV_2D

Same model works on BACKEND_OPENVINO+TARGET_CPU and BACKEND_OPENCV+TARGET_OPENCL
This is the first time I try inferring with a mobileone model, I suspect it never worked with previous release of OpenCV

Steps to reproduce

I can invite you to a private repository for a reproducer (those who know me already have access to it)

Issue submission checklist

• I report the issue, it's not a question
• I checked the problem with documentation, FAQ, open issues, forum.opencv.org, Stack Overflow, etc and have not found any solution
• I updated to the latest OpenCV version and the issue is still there
• There is reproducer code and related data files (videos, images, onnx, etc)