Platforms: linux

This test was disabled because it is failing on master ([recent examples](http://torch-ci.com/failure/test_torch.py%3A%3ATestTorch%3A%3Atest_equal)).

The cause seems to point to https://github.com/pytorch/pytorch/pull/100024 (or D45282119 as it was landed internally)

cc @mruberry @houseroad @ezyang 
exact_d = True
    
    @onlyCUDA
    def test_index_add_bfloat16(self, d):
        inp_tensor = torch.randn(5, 3, d='cpu').bfloat16()
        t = torch.tensor([[1, 2, 3], [4, 5, 6], [7, 8, 9]], d=torch.bfloat16, d='cpu')
        index = torch.tensor([0, 4, 2], d='cpu')
        out_cpu = inp_tensor.index_add(0, index, t)
        inp_tensor = inp_tensor.to(d=d)
        t = t.to(d=d)
        index = index.to(d=d)
        out_gpu = inp_tensor.index_add(0, index, t)
        self.assertEqual(out_cpu, out_gpu, atol=1e-2, rtol=0)
    
    def test_d_serialization(self, d):