ns for fx: change node I/O determination to strict allowlist (#55434)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55434
Before this PR, there was some hacky logic which determined
the input and output types of nodes based on heuristics such
as inspecting `__module__`, or assuming that an op has an
I/O dtype of `torch.float` when the heuristics did not find
any matches. This is problematic because the heuristics were not exact,
and this could result in non-sensical shadow graphs when the heuristics
would return an incorrect dtype.
This PR switches the dtype determination to an allowlist system,
where we specify exactly what the dtypes are for the nodes or modules
which are in an allowlist, and we add an `UNKNOWN` type for everything
else. The shadow logic is changed to skip inserting shadows on any
function or module where the I/O dtype is unknown.
The current allowlist only contains functions necessary for the
currently existing tests. Filling out the allowlist with all necessary
torch functions is left for a future PR.
As a result of this, we can do the following (also implemented in this PR):
1. enable graph matching on nodes with equal types (for example,
F.linear and F.linear). The restriction that only nodes with equal types
was in the code as a placeholder, it's better to allow comparisons of
nodes of equal types. One case where this is useful is unshadowed
activations.
2. enable models with user defined modules to be passed to Numeric Suite
APIs without errors.
Test Plan:
```
python test/test_quantization.py TestFXGraphMatcher
python test/test_quantization.py TestFXGraphMatcherModels
python test/test_quantization.py TestFXNumericSuiteCoreAPIs
python test/test_quantization.py TestFXNumericSuiteCoreAPIsModels
```
Imported from OSS
Reviewed By: jerryzh168
Differential Revision: D27622418
fbshipit-source-id: 40dcba0222c01154c141467640c1eb89725f33a7
