add if in register_buffer like register_parameters (#16110)
Summary:
without this "if", code below will throw error " Linear' object has no attribute '_buffers' "
And with this if, error would be "cannot assign buffer before Module.\_\_init\_\_() call", which I think it's more accurate, just like register_parameter.
```
import math
import torch
from torch.nn.parameter import Parameter
from torch.nn import functional as F
from torch.nn import Module
class Linear(Module):
def __init__(self, in_features, out_features, bias=True):
self.in_features = in_features
self.out_features = out_features
self.register_buffer('test', torch.Tensor(out_features, in_features))
self.weight = Parameter(torch.Tensor(out_features, in_features))
if bias:
self.bias = Parameter(torch.Tensor(out_features))
else:
self.register_parameter('bias', None)
super(Linear, self).__init__()
self.reset_parameters()
def reset_parameters(self):
stdv = 1. / math.sqrt(self.weight.size(1))
self.weight.data.uniform_(-stdv, stdv)
if self.bias is not None:
self.bias.data.uniform_(-stdv, stdv)
def forward(self, input):
return F.linear(input, self.weight, self.bias)
def extra_repr(self):
return 'in_features={}, out_features={}, bias={}'.format(
self.in_features, self.out_features, self.bias is not None
)
linear = Linear(3,4)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16110
Differential Revision: D13715839
Pulled By: soumith
fbshipit-source-id: c300eff0a8655aade448354cf489a592f7db722a
