I was curious what hf_T5_generate was trying to deepcopy, so I updated the errror message:
Before:
```
STATS graph_break
("'skip function deepcopy in file /home/jansel/conda/envs/pytorch/lib/python3.10/copy.py'', skipped according skipfiles.SKIP_DIRS'", 3)
...
```
After:
```
STATS graph_break
('copy.deepcopy UserDefinedObjectVariable(GenerationConfig)', 3)
...
```
Related issue: #115122
Pull Request resolved: https://github.com/pytorch/pytorch/pull/115120
Approved by: https://github.com/oulgen
ghstack dependencies: #115095, #115046, #115057, #115119
**Dynamo**
We don't want setattr in the graph. Setting data has interesting implications on both aliasing and on the autograd engine.
The safe recipe is:
1) Disable grad
2) Call set_()
3) Manually lower the version counter on the object to hide it from the autograd engine
This is effectively the same exact thing as setting .data, and it composes properly with aot_autograd and inductor.
**aot_autograd**
For aot_autograd, there's another snag.
Specifically, when we invoke aot_autograd, we call `fake_mode.from_tensor()`, relying on memo to get the right tensor out. For .data mutations, this doesn't work, because the memoized fake_tensor is in the state it will be in at the end of the trace, not at the beginning. This means that the .data call is already applied, and the tensor shape (as in the case of these tests) mismatches. aot_autograd produces an invalid graph, with illegal calls like `torch.ops.aten.view.default(primals_2, [0])` where primals is actually sized `([6])` on input.
The new plan here is to:
1) Record tensor fakification policy in dynamo
2) provide a fresh fake mode to all backends
3) Invoke from_tensor with the stored policy to get fresh new fake tensors in aot_autograd
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113080
Approved by: https://github.com/bdhirsh
This PR add should_flatten_outpu=True for cond. This effectively allows cond to support pytree output with the output being flattened. Note: a single tensor output will be automatically casted as tuple for torch.ops.higher_order.cond.
This PR also adds support for comparing BuiltinVariables e.g. tuple, this is to make sure we could make dynamo inline comparing two tree_spec to make sure both branches returns the same tree_spec.
Test Plan:
Existing tests. Will add more pytree tests and modify the documentations in the follow-up prs.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113819
Approved by: https://github.com/zou3519
In TorchVision we use the following (simplified) dispatch mechanism:
```python
import torch
def kernel1(tensor):
return tensor + 2
def dispatcher1(input):
kernel = get_kernel(dispatcher1, type(input))
return kernel(input)
def kernel2(tensor):
return tensor - 2
def dispatcher2(input):
kernel = get_kernel(dispatcher2, type(input))
return kernel(input)
# We actually use the function and type as keys, rather than their names.
# However, this currently not supported, but should be easy to add after
# https://github.com/pytorch/pytorch/pull/111196
REGISTRY = {
"dispatcher1": {"Tensor": kernel1},
"dispatcher2": {"Tensor": kernel2},
}
def get_kernel(dispatcher, input_type):
dispatcher_registry = REGISTRY[dispatcher.__name__]
for cls in input_type.__mro__:
kernel = dispatcher_registry[cls.__name__]
break
return kernel
```
This can be compiled without graph breaks:
```python
cfn = torch.compile(dispatcher1, fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 5)
cfn = torch.compile(dispatcher2, fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 1)
```
However, if we start chaining these calls, we hit some issues:
```python
class Pipeline(torch.nn.Module):
def forward(self, input):
input = dispatcher1(input)
input = dispatcher2(input)
return input
cfn = torch.compile(Pipeline(), fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 3)
```
```
Can't access members of type(obj) for a generated custom object. Please use __class__ instead
```
The error message is not really helpful here. The following happens: when compiling `dispatcher1`, `get_kernel` gets inlined. That means when hitting `dispatcher2`, the `type` call no longer happens on an input with a source. Thus, in the first iteration we hit the top branch, while in the second we hit the bottom:
addb8e29cd/torch/_dynamo/variables/builtin.py (L1264-L1268)
And the error message I posted above originates from the type being treated as constant. This PR replaces this with a `SourcelessBuilder` instead.
With that fix in place, we hit another pointing to `input_type.__mro__`
```
AssertionError: Consider SourcelessBuilder for ephemeral objects, usually objects created locally.
```
Fix is similar: instead of using a `VariableBuilder` here, we use a `SourcelessBuilder` in case we have no `source`:
addb8e29cd/torch/_dynamo/variables/builtin.py (L1167-L1168)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113340
Approved by: https://github.com/peterbell10, https://github.com/lezcano
This prepares the PR where we implement sets in terms of dicts.
To do so, rather than storing internally a dictionary that maps literals
to VariableTrackers, it stores (pretty much) a dictionary from VTs to VTs.
To do so, keys are wrapped in an opaque internal class `_Hashable`.
The Hashable class is opaque on purpose so that it fails hard if
if it inadvertently leaks back into user code.
We also found and fixed a number of latent bugs and inconsistencies
in the way dynamo checked what can be a dict key. More generally, we
make much clearer what are the things that need to be modified to add
a new supported key type to Dicts.
Fixes https://github.com/pytorch/pytorch/issues/107595
Fixes https://github.com/pytorch/pytorch/issues/111603
Pull Request resolved: https://github.com/pytorch/pytorch/pull/111196
Approved by: https://github.com/jansel
In TorchVision we use the following (simplified) dispatch mechanism:
```python
import torch
def kernel1(tensor):
return tensor + 2
def dispatcher1(input):
kernel = get_kernel(dispatcher1, type(input))
return kernel(input)
def kernel2(tensor):
return tensor - 2
def dispatcher2(input):
kernel = get_kernel(dispatcher2, type(input))
return kernel(input)
# We actually use the function and type as keys, rather than their names.
# However, this currently not supported, but should be easy to add after
# https://github.com/pytorch/pytorch/pull/111196
REGISTRY = {
"dispatcher1": {"Tensor": kernel1},
"dispatcher2": {"Tensor": kernel2},
}
def get_kernel(dispatcher, input_type):
dispatcher_registry = REGISTRY[dispatcher.__name__]
for cls in input_type.__mro__:
kernel = dispatcher_registry[cls.__name__]
break
return kernel
```
This can be compiled without graph breaks:
```python
cfn = torch.compile(dispatcher1, fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 5)
cfn = torch.compile(dispatcher2, fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 1)
```
However, if we start chaining these calls, we hit some issues:
```python
class Pipeline(torch.nn.Module):
def forward(self, input):
input = dispatcher1(input)
input = dispatcher2(input)
return input
cfn = torch.compile(Pipeline(), fullgraph=True)
torch.testing.assert_close(int(cfn(torch.tensor(3))), 3)
```
```
Can't access members of type(obj) for a generated custom object. Please use __class__ instead
```
The error message is not really helpful here. The following happens: when compiling `dispatcher1`, `get_kernel` gets inlined. That means when hitting `dispatcher2`, the `type` call no longer happens on an input with a source. Thus, in the first iteration we hit the top branch, while in the second we hit the bottom:
addb8e29cd/torch/_dynamo/variables/builtin.py (L1264-L1268)
And the error message I posted above originates from the type being treated as constant. This PR replaces this with a `SourcelessBuilder` instead.
With that fix in place, we hit another pointing to `input_type.__mro__`
```
AssertionError: Consider SourcelessBuilder for ephemeral objects, usually objects created locally.
```
Fix is similar: instead of using a `VariableBuilder` here, we use a `SourcelessBuilder` in case we have no `source`:
addb8e29cd/torch/_dynamo/variables/builtin.py (L1167-L1168)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113340
Approved by: https://github.com/peterbell10, https://github.com/lezcano
Subsumes https://github.com/pytorch/pytorch/pull/110794
Fixes https://github.com/pytorch/pytorch/issues/110315
This is not really a 100% sound fix, a deeper analysis of the bug can be found at https://docs.google.com/document/d/1y-nRAPdbZEji52MPKYzC0U3VhvW9yEAEDqP5t5GhWZ0/edit
The general idea behind the fix here is that we are going to play fast and loose with user defined classes: as Dynamo is written today, we are willing to pull out these types and directly manipulate them (e.g., look at their `__mro__`, etc) without an intervening VariableTracker. As such, if I use `python_type` to extract out the Python type of a VT or if I am manually reading out the `__bases__` of a type, which may be a user defined class, if it is sourceless, all I need to do is use SourcelessBuilder instead of ConstantVariable to make sure I wrap it into the correct VT class.
The approach in https://github.com/pytorch/pytorch/pull/110794 was "more correct", but we'd have to go substantially further to get it all working. So I am doing this to unblock suo for now.
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113390
Approved by: https://github.com/suo
Summary:
Python allows users to write code like
```
x: 1
x += y
x += z
```
This code has well-defined semantics: because x is an immutable primitive, the first `+=` will actually re-bind x, it is equivalent to `x = x + y`.
The second in-place operation will either similarly desugar (if the result of `x + y` is itself immutable), or possibly result in "true" in-place operation.
Now, this is a problem for us because today, dynamo tries to both resolve constant variables to their literal values at compile time and also compile in a way that treats `operator.*` builtin functions consistently. This leads to a bug where code like
```
x: 1
x += y
```
actually gets compiled to
```
1 += y
```
which is both semantically meaningless and a syntax error.
A very simple fix that we've already used to fix the special case of `+=` is to detect this, treat it as an edge case, and desugar eagerly into `x = x + y`.
The problem with that fix is that it only patched `iadd`, but actually *all* of the in-place operators exhibit this behavior.
This commit proposes that we tackle all of the inplace opeartors supported by fx in the same way: eagerly remap the operation to an assignment when the left-side is actually an immutable constant.
**Alternatives?**
There might be some other fix possible that wouldn't produce a hardcoded remapping; I know that we generally don't like the growth of mappings and blocklists in dynamo.
I'm a little skeptical about a general solution though, because the bug is due precisely to Python's highly dynamic dispatching of inplace operations by type; since the fx graph has to be purely static, I suspect that we actually have to desugar this somewhere, because the dataflow is fundamentally different for true inplace operations on types that define `__iadd__`, etc vs the desugaring on primitives.
I'm open to other suggestions
Test Plan:
I verified that the code in
https://github.com/pytorch/pytorch/issues/112656
compiles with this fix, and the compiled functions produce the same outputs as the originals.
This needs unit tests, but I'd like to get feedback on the approach in the meantime.
Fixes#112656
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113117
Approved by: https://github.com/yanboliang
Main: `RuntimeError: element 0 of tensors does not require grad and does not have a grad_fn`
This PR: graph breaks and eager applies the mutation, new tensors are tracked
Fixes https://github.com/pytorch/pytorch/issues/109505 (the original bug does not occur, but a new bug where the mutation isn't applied - because AOTAutograd is not `requires_grad` mutation aware - is mitigated)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113163
Approved by: https://github.com/bdhirsh
This PR enables AC + torch.compile to work with FSDP + TP, the fix to
high order op path is that we need to check both tensor and tensor
subclass bases to make sourceless builder
NOTE: selective AC + 2D is still not working, need to fix this
separately
Pull Request resolved: https://github.com/pytorch/pytorch/pull/112536
Approved by: https://github.com/yf225
Main: `RuntimeError: element 0 of tensors does not require grad and does not have a grad_fn`
This PR: graph breaks and eager applies the mutation, new tensors are tracked
Fixes https://github.com/pytorch/pytorch/issues/109505 (the original bug does not occur, but a new bug where the mutation isn't applied - because AOTAutograd is not `requires_grad` mutation aware - is mitigated)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113163
Approved by: https://github.com/bdhirsh
Fixes https://github.com/pytorch/pytorch/issues/112446
This is a doozy of a PR, there's a few important things to keep in mind here:
1) We MUST lift all tensors accessed via attrs to inputs, getattr is a no go in the graph, it violates the aot_autograd contract. Furthermore, aot_autograd does not know how to apply in-place ops to intermediary tensors that are attributes (aka from getattr) anyway. Views from ops are fine.
2) `.grad` access handling in dynamo peeks at the underlying value, the real tensor, because re-piping FakeTensors already made with this fake_mode through builder anew is a no go.
3) We have no proper mechanism for updating the hint / grapharg.example (the real value in (2) above) midway through trace
Therefore, what we need to do is reconcile the difference in grad stashed on grapharg.example. The easiest way to do this is lazily, upon .grad access, by reading the new value off the right fake tensors. We can then make a tensor using that data as a hint to VariableBuilder to make the right VariableTracker. Note that the example value used here (torch.zeros) in the PR, is a dummy value only used as a tracing hint, it does not leak out into real runtime code.
Alternatively, we could implement accumulate_grad_ in python...
Pull Request resolved: https://github.com/pytorch/pytorch/pull/112811
Approved by: https://github.com/jansel
Fixes https://github.com/pytorch/pytorch/issues/113030
Alias information needs to be applied in eager before we can continue to trace the graph.
----
Perhaps this is too strict - couldn't we fx trace through the in-graph (pointer) aliasing, and track mutations through fake tensors instead, and still apply the aliasing mutation epilogue for further mutations outside of graph? 🤔
Regardless, it didn't seem to work too well when I tried this. Seems that `Tensor.__setattr__` doesn't work well in fx graph.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113043
Approved by: https://github.com/ezyang, https://github.com/voznesenskym
Major change in this PR is to make torch context manager class a separate ```TorchCtxManagerClassVariable```, since we have dynamo implementation for these ctx managers.
I was thinking to wrap them as ```UserDefinedClassVariable``` and do dispatch at ```USCVariable.call_function```, but it seems almost the same amount of work and this way is more clear.
This is on the way of moving ```TorchVariable``` to ```TorchFunctionVariable``` which will only handle the functions who would be allowed in graph (e.g, ```torch.sin```) and constant folded (e.g, ```torch.is_floating_point```). All other torch functions would be go through skip/inline rules, and would be wrapped as ```UserFunctionVariable``` (for inlined) and ```SkipFilesVariable``` (for skipped).
The next steps:
* Wrap torch modules, classes, objects as regular ```PythonModuleVariable```, ```UserDefinedClassVariable``` and ```UserDefinedObjectVariable```.
* Generate the allow in graph torch functions list and wrap them as ```TorchFunctionVariable```.
* Finally merge ```skipfiles.check``` and ```is_allowed``` into one function ```allow_skip.check(fn)``` which would return a Enum of allow, skip and inline.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/111622
Approved by: https://github.com/jansel
This PR implements 2 things:
1. support the device agnostic stream and runtime APIs captured by the dynamo.
2. support the stream methods(include the event) captured by the dynamo.
Here are details for 1st.
Previously the stream captured in dynamo was tightly bind to CUDA. Here we implement a global singleton container named `StreamMethodContainer` for different backends to register their associated stream methods to dynamo. When import the backend’s product, the stream operations can be registered directly by calling
```
device_stream_method = {'current_stream': method_1,
'create_stream_context': method_2,
'set_stream': method_3,
'set_stream_by_id': method_4}
torch._dynamo.stream.register_stream_method(device_name, device_stream_method)
```
Stream methods need to be passed in this API according to the precise semantics represented by the dict key in `device_stream_method`. After register, these methods can be used by dynamo to capture the stream operations in users’ script, for example, get the current stream or set the specific stream. Additionally, the wrapped stream variable and the stream context variable are changed to be the device-agnostic, the proxy functions of these variables are assigned by the associated methods in the container. All of this are illustrated in the below. Below is a illustration.

Pull Request resolved: https://github.com/pytorch/pytorch/pull/108312
Approved by: https://github.com/jansel, https://github.com/jgong5
We want to get to a point where most UserErrors link to exportdb examples. This PR makes passing case names non-optional to make this intent clearer and encourage developers who raise UserErrors to make or point to examples that make fixing such errors more obvious for users.
In addition, sometimes there are multiple examples that are relevant to an error. Thus this PR also enables passing multiple case names.
Retry of #110733 which was reverted due to a landrace.
Differential Revision: [D50087148](https://our.internmc.facebook.com/intern/diff/D50087148/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/110878
Approved by: https://github.com/gmagogsfm, https://github.com/tugsbayasgalan
The motivation for removing this is already present in the pre-PR comments. Copying it
~~~
# NB - SuperSource is a weird one.
# it is our only source with 2 bases, so we use the objec
# as the base, rather than the type, since an invocation
# like super(Foo, foo) is represented here, the source object base is more spiritually
# aligned with the instance, rather than the type.
# This whole construction is questionable tho, and we should probably find a way to
# avoid this exception to our otherwise nice source parentage invariant.
~~~
Instead of using super(a, b), we can use `type(b).__mro__[index]`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/110475
Approved by: https://github.com/jansel
We want to get to a point where most `UserError`s link to `exportdb` examples. This PR makes passing case names non-optional to make this intent clearer and encourage developers who raise `UserError`s to make or point to examples that make fixing such errors more obvious for users.
In addition, sometimes there are multiple examples that are relevant to an error. Thus this PR also enables passing multiple case names.
Differential Revision: [D50020465](https://our.internmc.facebook.com/intern/diff/D50020465/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/110733
Approved by: https://github.com/zhxchen17
Ideally all `_dynamo.exc.UserError`s should have "case names", i.e., link to examples in `exportdb`.
This PR adds case names to several instances of `_dynamo.exc.UserError`. In particular, looking at coverage based on `UserErrorType`:
* `DYNAMIC_CONTROL_FLOW`, `ANTI_PATTERN`, and `STANDARD_LIBRARY` are fully covered.
* `CONSTRAINT_VIOLATION` and `DYNAMIC_DIM` have no coverage. We don't seem to have any dedicated examples of specifying dynamic shapes in `exportdb` (although they are used in some other examples without explanation, to avoid some specialization that would make such examples moot).
* `INVALID_INPUT` is only partly covered. Frankly this is tedious to cover via examples.
Differential Revision: [D49928518](https://our.internmc.facebook.com/intern/diff/D49928518/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/110555
Approved by: https://github.com/angelayi, https://github.com/ydwu4