Not to be confused with THC/THNN/THCUNN, there the list is bigger.
Based on native_functions.yaml

• _th_put
• _th_index_fill
• _th_renorm
• _th_trace
• _th_nonzero
• _th_gels
• _th_potri Port cholesky_inverse to ATen #50269
• _th_geqrf Port CPU torch.geqrf to ATen #56249
• _th_orgqr Port CPU torch.orgqr to ATen #50502
• _th_ormqr Port CPU torch.ormqr to ATen #57315
• _multinomial_alias_setup
• _th_histc
• _th_var
• _th_std

Most of them are linear algebra, should be ported._multinomial_alias_setup is likely not used. We should get rid of them, we can do it!

cc @jianyuh @nikitaved @pearu @mruberry @heitorschueroff @walterddr