Avoid overwrite of compiled module wrapper attributes (#5549)
**Fix overwriting of the compiled wrapper class attributes by those of
the wrapped class itself: Copy only those attributes which are not
already present in the wrapper.**
In the current implementation of the `CompiledModuleWrapper` the wrapper
attributes (eg `forward` method) are overwritten by `self._dict_ =
module._dict_.copy()`:
```
def CompiledModuleWrapper(mod, compile_config: Union[CompileConfig, None] = None):
class wrapper(mod.__class__):
def __init__(self, module, compile_config: Union[CompileConfig, None] = None):
self.__dict__ = module.__dict__.copy()
```
This causes the `wrapper`'s `forward` method not being called and,
consequently, the wrapped module not compiled. Instead, the wrapped
module `forward` method is being called as illustrated in the diagram
below (a real scenario from Deespeed-Chat):
The proposed fix copies only those attributes which are not present in
the wrapper class, thus implementing the desired inheritance quality of
the wrapper.
Attached is a simple reproducer of the problem.
[compiled_module_wrapper_bug.zip](https://github.com/microsoft/DeepSpeed/files/15378282/compiled_module_wrapper_bug.zip)
Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>
