Hello，it really made me confused when reading the @SimonW refered source code in AutoGrad about the Conv2d 13.
When i read the detail of  function THNN_(SpatialConvolutionMM_updateGradInput) 13, Could any warm-kinded people tell me the meaning of gradInput, gradOutput and gradColums and the correct order of reading Autograd mechanism used in Conv2d?
Thanks a lot, Really need your help!