Adding missing cudnnSetConvolutionGroupCount to pointers.json

[arhik]

This change is necessary for setting groupcount incase of depthwise and groupwise convolutions.

The original cudnn api is as follows:

cudnnStatus_t cudnnSetConvolutionGroupCount(
cudnnConvolutionDescriptor_t convDesc,
int groupCount)

[maleadt]

Why do you need this entry? We only need it to resolve pointer arguments, which this call doesn't have.

[maleadt]

We have the wrapper already:

CuArrays.jl/src/dnn/libcudnn.jl

Lines 388 to 392 in b64c6c0

	function cudnnSetConvolutionGroupCount(convDesc, groupCount)
	@check @runtime_ccall((:cudnnSetConvolutionGroupCount, libcudnn[]), cudnnStatus_t,
	(cudnnConvolutionDescriptor_t, Cint),
	convDesc, groupCount)
	end

[arhik]

Sorry. Function pointer was returning null so I assumed its missing. I didn't realized its declared at other place. Thanks.

Why do you need this entry? We only need it to resolve pointer arguments, which this call doesn't have.

I was just following other definitions. I was curious to know the purpose of null declarations as a followup. You have shed some light on it. Interesting!

[maleadt]

Yeah, this stuff isn't documented at all, purely internal for generating wrappers. null indicates this argument isn't special, and can be used as-is. In other cases, when dealing with pointers, the argument indicates what kind of pointer we're dealing with (a pointer to CPU memory, to GPU memory, or to potentially both).