Fusion and _intrinsic modules (#23003)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23003
torch.quantization.fuse_module and torch.nn._intrinsic convRelu and LinearRelu
Fusion function to combine specific modules: (conv,bn) and (conv,bn,relu).
In all cases, replace modules in place. The first module is replaced with the _intrinsic fused module and the remaining modules are replaced by nn.Identity.
Support both training and eval. For training, the modules are "fused" with a sequential container. This is to allow for further module swaps for quantization aware training.
Also add: torch.nn._intrinsic for convRelu and LinearRelu.
TODO: Add tests for _intrinsic modules.
Conv BN fusion code is based on DsKhudia's implementation
Differential Revision: D16199720
fbshipit-source-id: 95fb9ffe72b361d280313b2ec57de2acd4f9dda2
