Add torch.utils._sympy.interp (#94985)
This utility allows us to conveniently abstract interpret Sympy expressions with respect to some alternative domain. I am particularly interested in using ValueRanges to do range analysis on expressions (not this PR).
Some minor house-keeping:
* ReferenceAnalysis got moved to its own file, sprouted a constant() implementation, and some uses of math.* got converted to sympy.*
* ValueRangeAnalysis now understands mod
* Test file gets moved from `test_value_ranges.py` to `test_sympy_utils.py`
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94985
Approved by: https://github.com/eellison
