Previously, x.size(0) could return a SymInt, even when the internal
sympy expression was actually already constant (e.g., due to an
introduced guard.) We now allow to query the Python object with
maybe_as_int which allows us to transmute these objects back to
int when possible.
It is still possible to end up with a constant SymInt even after this
change, e.g., if you get out a SymInt and while holding onto it
specialize it, but casual users are more likely to get ints when they
want to.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/104828
Approved by: https://github.com/Skylion007
Previously, x.size(0) could return a SymInt, even when the internal
sympy expression was actually already constant (e.g., due to an
introduced guard.) We now allow to query the Python object with
maybe_as_int which allows us to transmute these objects back to
int when possible.
It is still possible to end up with a constant SymInt even after this
change, e.g., if you get out a SymInt and while holding onto it
specialize it, but casual users are more likely to get ints when they
want to.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/104828
Approved by: https://github.com/Skylion007
Previously, x.size(0) could return a SymInt, even when the internal
sympy expression was actually already constant (e.g., due to an
introduced guard.) We now allow to query the Python object with
maybe_as_int which allows us to transmute these objects back to
int when possible.
It is still possible to end up with a constant SymInt even after this
change, e.g., if you get out a SymInt and while holding onto it
specialize it, but casual users are more likely to get ints when they
want to.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/104828
Approved by: https://github.com/Skylion007
This PR introduces value range refinement of shape symbols by symbolically evaluating the
value range of the involved guards. This should help `_maybe_evaluate_static` to eliminate
more guards.
This is a stack of PRs created from the discussion on: #96616.
In summary, this PR:
- simplifies `FloorDiv` nodes on the left-hand side of an expression so as to isolate a
symbol in the numerator
- tries to match the expression against the form: `<symbol> <relop> <expr>`
- uses the matched expression for refining the value range of `<symbol>` using the range
of `<expr>`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/97963
Approved by: https://github.com/ezyang
This PR turns translation validation on by default for tests and accuracy benchmark
runs. It also installs Z3 on CI.
The main changes are:
- Add `--no-translation-validation` as an option in _test/run_tests.py_
- Set `PYTORCH_TEST_WITH_TV` environment variable
- Add `TEST_WITH_TV` variable in _torch/testing/_internal/common_utils.py_
- Turn translation validation on for accuracy benchmarks in _benchmarks/dynamo/common.py_
- Add Z3 installation on CI scripts
Pull Request resolved: https://github.com/pytorch/pytorch/pull/103611
Approved by: https://github.com/ezyang
This PR adds support for `enable_grad`/`no_grad`/`autocast` context managers getting properly traced in `pre_dispatch` tracing. The stuff in this PR includes:
- I added a torch function mode that runs during make_fx pre_dispatch tracing, `ProxyTorchFunctionMode`. It directly intercepts the torch ops that run during the above context managers, and adds them to the current graph instead of executing them
- `enable_grad` and `no_grad` currently desugar into `torch._C.set_grad_enabled(bool)`, but this API isn't currently overrideable by torch function so I added the ability to interpose there
- the `torch.amp` context managers don't currently have a nice equivalent, like `set_autocast_enabled(state)`, so I ended up adding two new API's: `torch.amp._set_autocast_enabled` and `torch.amp._set_autocast_disabled`. If you look at how the context manager is implemented, it ends up calling several different state-changing functions, some of which depend on the backend - so I figured that it would be cleaner just to add a new API (that should probably only be used by tracing) - but open to feedback
- I added a new dynamo backend, `compile(backend="pre_dispatch_eager")`. When pre_dispatch tracing becomes always-on in inductor, it will be another potential surface for bugs. I also added a test file for it (`test/dynamo/test_pre_dispatch.py`).
Pull Request resolved: https://github.com/pytorch/pytorch/pull/103024
Approved by: https://github.com/ezyang
This is in preparation for the custom_op_compile_check utility, which
will call the newly refactored function.
This PR:
- splits off code into helper functions
- adds clearer error messages
- stops updating the inputs destructively (leading to slightly slower
tests)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/103196
Approved by: https://github.com/bdhirsh, https://github.com/soulitzer
We discussed in a composability meeting a few weeks ago that `pre_autograd` should probably be renamed to `pre_dispatch`.
One question in this PR was: should I re-use a dispatch key? Or should I create a new dispatch key (that yet again corresponds to "top of the dispatcher")?
~~For now, I ended up sticking our proxy mode on the mode stack corresponding to `PythonTLSSnapshot`, because it was simple and it works. It looks like one of the functorch dispatch keys has higher priority though, so it's possible that functorch will end up running first. Open to options, but we can consider adding a new dispatch key later if that becomes a problem~~
Update: I added a dedicated dispatch key, `PreDispatch`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/101818
Approved by: https://github.com/ezyang, https://github.com/Neilblaze, https://github.com/albanD, https://github.com/zou3519
When investigating failures in https://github.com/pytorch/pytorch/pull/100017 I realized that we were reentering FakeTensorMode even though there was already one on the stack. Although we have attempted assert for these cases in the past, e.g., as in https://github.com/pytorch/pytorch/pull/97186 it seems that the existing protections were insufficient.
In this particular case, the reapplication of FakeTensorMode was due to an interaction with NotImplemented multiple dispatch handling. If proxy tensor mode detects an unrecognized tensor type (this includes FakeTensor, if it is not tracked with a proxy), it will return NotImplemented to give this tensor a chance to unpack itself into proxyable operation. However, this is never the right thing for FakeTensor, where no unpacking is possible. However, today, FakeTensor attempts to reapply the FakeTensorMode, resulting in FakeTensorMode being twice on the stack.
This PR does a number of things:
* It adds an assert in `FakeTensorMode.__torch_dispatch__` that you must not already have this mode on the stack, this is ALWAYS an error
* It modifies `FakeTensor.__torch_dispatch__` to return `NotImplemented` if the mode is already active. This prevents us from readding the mode on the stack
* It adds a new logging artifact `not_implemented` which you can use to get debug logs about all of the times a `__torch_dispatch__` handler returned NotImplemented and why it did so. Your subclass has to manually opt into this logging, but I inserted the necessary logs for ProxyTensorMode and FakeTensor(Mode)
* `with fake_mode` now no-ops if the fake mode is already on the stack, which is what users want anyway
* I am BREAKING pre-autograd tracing, because it is currently doing something weird with the original C++ mode stack. Brian is going to follow up with a fix next week.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/102091
Approved by: https://github.com/thiagocrepaldi, https://github.com/eellison, https://github.com/wanchaol, https://github.com/bdhirsh
