Add SymInt::guard_int (#85139)
This allows you to explicitly guard on the specific integer value
of a SymInt so that you can condition on it. If possible, prefer
guarding on a boolean expression instead.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85139
Approved by: https://github.com/Chillee
