Warn on conditions that can trigger cuBLAS sgemm bug (#22034)
Summary:
The sgemm in cuBLAS 9.0 has some issues with sizes above 2M on Maxwell and Pascal architectures. Warn in this case.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22034
Differential Revision: D15949930
Pulled By: zhangguanheng66
fbshipit-source-id: 0af977ec7900c76328d23898071de9c23778ff8b
