Fix bugs in how LTC decides whether or not to symint op or not (#84832)
This fixes two problems:
- First, shape signature didn't respect the symint property (so it
would always mark the operator as symint). This was relatively
easy to fix.
- Second, the call to fallback goes directly through at::_ops, so
it must always be SymInt-aware, even if SymInt is disabled externally.
This was a bit more difficult, because the current LTC codegen
is poorly factored. First, I needed to make it so individual
arguments knew if they were going to be SymInt in LTC or not; second,
I need to plumb enough information about the enclosing bindings so
that I could use translate to do the expressions (previously, it was
just assumed the signatures matched.)
The LTC codegen would do well to have a complete rewrite, but this will
have to do for now, I suppose.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/84832
Approved by: https://github.com/wconstab
