Is there operator that can compute `a * x + b`

Hi,

I have 3 tensors, and I would like to compute this:

a = torch.randn(1, 32, 1, 1)
x = torch.randn(16, 32, 64, 64)
b = torch.randn(1, 32, 1, 1)
out = a *x + b

However, I found that this a *x + b is not built-in function which makes inference not as fast as expected. So is there any built in function that can compute this in the c++ side like this ?

out = some_func(a, x, b)

there is b.addcmul(a,x), jit code is another possibility