The goal of this multigraph work is to enable a compiled region that has a single dynamo trace but multiple backend specializations. This work was inspired by vLLM which does this in a somewhat hacky way where they use a custom backend to capture a dynamo graph and then manually invoke compile_fx multiple times to get specialized graphs.
There's really two parts of this work:
**The frontend changes:**
1) we introduce an optional kwarg `specialize_on` to mark_{dynamic,unbacked} that takes in a list of specializations. I debated other methods including specifying specializations via decorators, but ultimately decided this approach was more harmonious. The big issue with decorators is the difficulty of composing well with the rest of the torch.compile ecosystem including graph breaks, lazy initialization of variable trackers and symbolic variables, etc.
**The backend changes (this PR):**
1) We capture the backend_specialization specified in the mark_{dynamic,unbacked} API into a SymbolicContext. See changes in `/_dynamo/variables/builder.py`
2) After we are done dynamo tracing, we will lazily (more on this later) invoke `call_user_compiler` up to N + 1 times for N specializations and 1 generic graph. Under the hood this will call compile_fx, which composes nicely with both Async Compile and AOTAutogradCache. We do this by using a context manager to patch in specialization specific axioms into the ShapeEnv before invoking the user compiler.
3) When we have specializations, we install a lazy specialized dispatch function that checks each specialization and dispatches to the first one that matches. Instead of doing all of the specialization compiles up front, we do the compiles lazily. The first time a specialization is invoked, we will do the compilation and save it in a cache so subsequent invocations are fast. If none of the specializations match, we dispatch to the generic graph. I decided to do this over returning N different GuardedCodes since 1) it doesn't pollute the dynamo cache (eg. if you have 8 specializations, you would hit the cache limit) 2) it naturally incorporates the hierarchical lattice structure of the guards since the specializations are always necessarily stricter than the generic region's guards.
I benchmarked this PR stack with #152596 and found around a 50% reduction when dispatching to the specialized regions:

Pull Request resolved: https://github.com/pytorch/pytorch/pull/153449
Approved by: https://github.com/zou3519
ghstack dependencies: #153433
Basically adds native _IntWrapper support to dynamo. Here's my process of trying to make symint input support work on dynamo, and how I ended up with this approach [(doc)](https://docs.google.com/document/d/1GvNRQd8BnxlMay_hrEVgEta6VUeUW_hcFeRuB7q1nDY/edit?tab=t.0).
What I did was, before passing inputs to dynamo.export, I first wrap them with a class, `_IntWrapper`. When processing dynamic shapes, I will then add the corresponding dynamic shape specification to the `dynamism` field stored on the `_IntWrapper`. If there is no dynamism specified, then this will get unwrapped back to an integer. When dynamo tracing, when we encounter an `_IntWrapper`, we will convert this to a symint if the dynamism was specified as `Dim.DYNAMIC/AUTO`. Dynamo will then trace a graph that contains symint inputs, which will get passed to AOTAutograd and so on.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/152677
Approved by: https://github.com/pianpwk
Implement traceable config patching for Dynamo: enables restricted patching of Dynamo config where user can use a context manager/decorator to change tracing behavior for parts of the code.
The new `dont_skip_tracing` decorator/context manager for ignoring most trace rules is easily implemented with this more generic traceable config patching feature.
Implementation:
- Create a new specialized context manager class representing a wrapper around torch._dynamo.config.patch
- Dynamo doesn't trace into the context manager but updates config at compile time
- Correctness is based on our correctness for handling supported context managers
- Implementation is inspired by how `GradModeVariable` is implemented.
Previous attempts: https://github.com/pytorch/pytorch/pull/148736 (decorator-only global approach) and https://github.com/pytorch/pytorch/pull/149439 (decorator-only traceback approach)
See https://docs.google.com/document/d/1vWNwKL_jpg-PLopifcaSa338wks3GqSVF4GHRguybGg/edit?tab=t.0 for more details on implementation - including previous approaches.
NOTE: this PR fixes a bug where skipped code objects were not tracked by convert_frame.py, leading to cases where code objects would be automatically skipped even after `torch._dynamo.reset()`. This exposed some latent dynamo-wrapped test failures in CI that previously passed in CI but not locally.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150586
Approved by: https://github.com/jansel, https://github.com/zou3519, https://github.com/anijain2305
As requested by Shuai. I also included an additional refactor to capture
changes in the whitelist over time since previously the first time it
was set, it was impossible override when a new config was set.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/151766
Approved by: https://github.com/pianpwk
Implement traceable config patching for Dynamo: enables restricted patching of Dynamo config where user can use a context manager/decorator to change tracing behavior for parts of the code.
The new `dont_skip_tracing` decorator/context manager for ignoring most trace rules is easily implemented with this more generic traceable config patching feature.
Implementation:
- Create a new specialized context manager class representing a wrapper around torch._dynamo.config.patch
- Dynamo doesn't trace into the context manager but updates config at compile time
- Correctness is based on our correctness for handling supported context managers
- Implementation is inspired by how `GradModeVariable` is implemented.
Previous attempts: https://github.com/pytorch/pytorch/pull/148736 (decorator-only global approach) and https://github.com/pytorch/pytorch/pull/149439 (decorator-only traceback approach)
See https://docs.google.com/document/d/1vWNwKL_jpg-PLopifcaSa338wks3GqSVF4GHRguybGg/edit?tab=t.0 for more details on implementation - including previous approaches.
NOTE: this PR fixes a bug where skipped code objects were not tracked by convert_frame.py, leading to cases where code objects would be automatically skipped even after `torch._dynamo.reset()`. This exposed some latent dynamo-wrapped test failures in CI that previously passed in CI but not locally.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150586
Approved by: https://github.com/jansel, https://github.com/zou3519, https://github.com/anijain2305
This patch effectively ignores traceable_tensor_subclasses, allowing
Dynamo to always try tracing into the `__torch_function__` of tensor
subclass. This helps us with 2 things:
1. allowing users to directly benefit from better compilation of tensor
subclass, by just upgrading pytorch, without having to change legacy
library code (see earlier patches in the stack for examples).
2. potentially exposing more issues in compiling tensor subclass, so we
can get signals and improve them.
As a consequence, it exposed and fixes 2 subtle bugs:
1. In `build_torch_function_fn`, we could get
`torch._C._disabled_torch_function_impl` because we have a
`Parameter` subclass without `__torch_function__` override or if we
have a tensor subclass with `__torch_dispatch__` override. We graph
break on this for now, and plan to add support -- the logic for
simulating `torch._C._disabled_torch_function_impl` is already in
`SuperVariable`, we just need to reuse it.
2. Sometimes we create `SyntheticLocalSource` and need to remove all the
guards installed on it, but we only removed the ones whose source
_is_ the created synthetic source `s`, but forgot about chained
source like `s.foo`, this showed up as
`SYNTHETIC_LOCAL['tmp_0'].__torch_function__.__func__`.
Differential Revision: [D71906141](https://our.internmc.facebook.com/intern/diff/D71906141)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149792
Approved by: https://github.com/jansel, https://github.com/mlazos
ghstack dependencies: #149482, #149483, #149484
This fixes most of https://github.com/huggingface/diffusers/issues/10795,
except for `torch.Tensor._make_subclass`, which will be fixed in a
subsequent patch.
The relevant tensor subclass from the aforementioned issue is defined
here: fbf6b856cc/src/diffusers/quantizers/gguf/utils.py (L398-L435).
There are two things to note about the tensor subclass:
1. it calls `super().__torch_function__`, which is
`torch._C._disabled_torch_function_impl`, so this patch updates
`SuperVariable.call_method` to handle it (we can't do a simpler
polyfill due to some bug with `var_getattr` raising
`NotImplementedError`, which forgot to restore symbolic context).
2. it sets and reads attributes (`quant_type`), and
defines new methods (`as_data`), so this patch adds support for those.
3. it has a `__init__`, which Dynamo needs to trace through in
`TensorSubclassVariable.call_function`.
Differential Revision: [D71906140](https://our.internmc.facebook.com/intern/diff/D71906140)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149482
Approved by: https://github.com/jansel, https://github.com/mlazos
This patch effectively ignores traceable_tensor_subclasses, allowing
Dynamo to always try tracing into the `__torch_function__` of tensor
subclass. This helps us with 2 things:
1. allowing users to directly benefit from better compilation of tensor
subclass, by just upgrading pytorch, without having to change legacy
library code (see earlier patches in the stack for examples).
2. potentially exposing more issues in compiling tensor subclass, so we
can get signals and improve them.
As a consequence, it exposed and fixes 2 subtle bugs:
1. In `build_torch_function_fn`, we could get
`torch._C._disabled_torch_function_impl` because we have a
`Parameter` subclass without `__torch_function__` override or if we
have a tensor subclass with `__torch_dispatch__` override. We graph
break on this for now, and plan to add support -- the logic for
simulating `torch._C._disabled_torch_function_impl` is already in
`SuperVariable`, we just need to reuse it.
2. Sometimes we create `SyntheticLocalSource` and need to remove all the
guards installed on it, but we only removed the ones whose source
_is_ the created synthetic source `s`, but forgot about chained
source like `s.foo`, this showed up as
`SYNTHETIC_LOCAL['tmp_0'].__torch_function__.__func__`.
Differential Revision: [D71906141](https://our.internmc.facebook.com/intern/diff/D71906141)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149792
Approved by: https://github.com/jansel, https://github.com/mlazos
ghstack dependencies: #149482, #149483, #149484
This fixes most of https://github.com/huggingface/diffusers/issues/10795,
except for `torch.Tensor._make_subclass`, which will be fixed in a
subsequent patch.
The relevant tensor subclass from the aforementioned issue is defined
here: fbf6b856cc/src/diffusers/quantizers/gguf/utils.py (L398-L435).
There are two things to note about the tensor subclass:
1. it calls `super().__torch_function__`, which is
`torch._C._disabled_torch_function_impl`, so this patch updates
`SuperVariable.call_method` to handle it (we can't do a simpler
polyfill due to some bug with `var_getattr` raising
`NotImplementedError`, which forgot to restore symbolic context).
2. it sets and reads attributes (`quant_type`), and
defines new methods (`as_data`), so this patch adds support for those.
3. it has a `__init__`, which Dynamo needs to trace through in
`TensorSubclassVariable.call_function`.
Differential Revision: [D71906140](https://our.internmc.facebook.com/intern/diff/D71906140)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149482
Approved by: https://github.com/jansel, https://github.com/mlazos
Fixes#139167
This PR:
* uses `named_buffers` to mark static
* Checks that `named_buffers` is of expected type (callable, iterator) before trying to iterate over; if not, we skip this pass
These changes fix the previous errors in dynamo causing to crash (as shown in issue above)
### Unit Test
```
python test/dynamo/test_buffers_override.py
```
Results in:
```
.
----------------------------------------------------------------------
Ran 2 tests in 5.344s
OK
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149882
Approved by: https://github.com/anijain2305
PR does following
* Turns `inference_mode` to False and `no_grad` for `convert_frame`, if the inference_mode is on globally.
* Turns off inference_mode for fake tensor prop. This ensures that converting from real inference tensor to a fake tensor removes the inference-ness.
* Graph breaks on is_inference and is_inference_mode_enabled.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149321
Approved by: https://github.com/jansel, https://github.com/zou3519
This allows for each device type to check current devices for Triton compatibility and ensure their Triton backend is present.
This PR replaces the `has_triton()` global method which was previously used for this task, and moves the initial check for each Inductor backend on to their associated `BaseScheduler` subclass. This means that other backends, such as Halide, can also implement their own availability checks.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/139171
Approved by: https://github.com/jansel
Recently I've been experimenting with introducing new APIs to delay compile as a way to reduce compile times while improving the ergonomics of using dynamic shapes. The high level idea is to run the first invocation of compile in eager, save the example inputs, and on the second invocation we can derive the dynamism in the inputs so that we don't need to waste our time doing a compile with static shapes (which is the status quo today with automatic dynamic).
Another benefit of this is most users no longer need to annotate their inputs with mark_dynamic and mark_unbaked calls since we can derive the dynamism on the very first call. Additionally we get dynamic ints out of the box in this new regime.
This PR implements this idea through the set_stance APIs. In particular it introduces a new `eager_then_compile` stance.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/147983
Approved by: https://github.com/williamwen42
This PR introduces the ability to whitelist sources as dynamic. This is particularly useful for large models with graph breaks, as you can keep the dynamism across graph breaks since source names stay consistent. Additionally you can use this to mark ints as dynamic.
NB: I intentionally didn't complicate the interface by supporting specification of per dimension dynamism. There is virtue in keeping true to the standard way of representing sources (eg. L['x']). If we find in practice that we need more more fine grained control, we can explore further affordances at that time.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/147979
Approved by: https://github.com/Mingming-Ding
Earlier, with inline flag we were lifting id-guarded tensors to the inputs to the Fx graph. But this offers no benefit. Main idea behind lifting parameters as inputs was to reuse the compilation units across many instances of the nn-module. However, if we are guarding on the `id`, we are explicitly specializing the compiled artifact to the parameter.
This PR installs the parameters back into the graph. The benefit is removal of all pre-graph bytecode to extract the id-guarded tensors from locals/globals. This increases speedup from 1.67x to 1.75x for an internal model that has large number of optimizer parameters.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/147824
Approved by: https://github.com/jansel
Co-authored-by: Jason Ansel <jansel@meta.com>