Matrix Multiplication optimization

I have deleted some part of my code due to space limitation while uploading but in that part, i am doing the matrix multiplication. I have tried to run this code step by step .i.e. commenting all the code for the first time and then uncomment it step by step to see which part is creating problem. while doing so, i have found that when i tried to save the updated value of calculation in already defined matrix, it gives me problem. I have mentioned those lines in "red font". when i don't include those lines in the code, everything works fine and analysis compilation takes only less than 10sec but when i include those two lines, analysis compilation takes app 40 mins. this is making me crazy. I just have to store the value in matrix so that i can use it in next clock cycle.