# Support unpacking python dictionary in **torch.jit.trace()**
## Problem statement & Motivation
### Problem 1(usability):
Say, if you have a model and its forward method defined as follows:
**`def forward(self, key1=value1, key2=value2, key3=value3)`**
And you have a dataset and each data point in the dataset is a python dict as follows:
**`data = {key1:value1, key3:value3, key2:value2}`**
The problem is that if you want to trace the model using the dict data by the giving dataset, you need unpack the dictionary and reorder its value manually and make up a tuple as **`data_tuple = (value1, value2, value3)`** as the **`example_inputs`** parameter of **`torch.jit.trace()`**. This marshalling process is not user friendly.
### Problem 2 (feasibility):
Say, if you have a model and its forward method defined as follows:
**`def forward(self, key1=None, key2=None, key3=None)`** -> The default value is **None**
And you have a dataset and each data point in the dataset is a python dict as follows:
**`data = {key1:value1, key3:value3}`** -> Only **part of** the required value by forward was given, the rest use the default value.
The problem is that if you want to trace the model using the dict data by the giving dataset, it's not feasible at all. Cause neither you can pass a tuple like **`T1 = (value1, value3)`** nor **`T2 = (value1, None, value3)`**. T1 will mismatch value3 with key2 and T2 include **None** type which will be blocked by tracer's type checking. (Of course you can pass **`T3 = (value1,)`** to make the trace function finish without exception, but the traced model you get probably is not what you expect cause the different input may result in different traced result.).
These problems come from the HuggingFace's PT model, especially in text-classification tasks with datasets such as [MRPC,](https://paperswithcode.com/dataset/mrpc) [MNLI](https://paperswithcode.com/dataset/multinli) etc.
## Solution
To address these two issues, we propose to support a new type, that is, python dict as example_inputs parameter for torch.jit.trace(). We can base on the runtime type information of the example_inputs object to determine if we fall back to the original tuple path or go into the new dictionary path. Both problem 1 and problem 2 can be solved by utilizing the "**`**`**"
operator.
## Limitation & Mitigation
1. If we use dict as example_inputs to trace the model, then we have to pass a dictionary to the traced model too. (Cause probably we will change the order of debug name of the input parameter in torchscript IR, thus we can't assume the traced model's input parameters order are the same with the original model.). We need highlight this too in the document to mitigate this problem.
For example:
```
# fetch a data from dataloader, and the data is a dictionary
# and the example_inputs_dict is like: {key1:value1, key3:value3, key2:value2}
# the forward() is like: def forward(self, key1=value1, key2=value2, key3=value3)
example_inputs_dict = next(iter(dataloader))
jit_model = model.eval()
# use the dictionary to trace the model
jit_model = torch.jit.trace(jit_model, example_inputs_dict, strict=False) # Now the IR will be graph(%self : __torch__.module.___torch_mangle_n.Mymodule, %key1 : type1, %key3 : type3, %key2 : type2)
jit_model = torch.jit.freeze(jit_model)
# It's OK to use dict as the parameter for traced model
jit_model(**example_inputs_dict)
example_inputs_tuple = (value1, value3, value2)
# It's wrong to rely on the original args order.
jit_model(*example_inputs_tuple)
```
## Note
1. This PR will make some UT introduced in [39601](https://github.com/pytorch/pytorch/pull/39601) fail, which I think should be classified as unpacking a tuple containing a single dictionary element in our solution.
4. I think there is ambiguity since currently we only specify passing a tuple or a single Tensor as our example_inputs parameter in **torch.jit.trace()**'s documentation, but it seems we can still passing a dictionary.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/81623
Approved by: https://github.com/davidberard98
Summary:
Previously `torch.jit.trace` relies on AutoGrad hooks to infer name of tensors in computation, including those of function/method arguments. This often doesn't work out because:
- These names often do not exist
- Tracer uses argument name of first tensor operation on each tensor as inferred argument names. These tensor operations have programmatically-generated names like `argument_1`
This PR extracts argument names directly from Python functions and pass them down to tracer, which then assigns them to correct graph inputs. This way, we always have the correct argument names captured in IR.
This is useful for both debugging and supporting using `InterfaceType` to represent traced modules.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51775
Reviewed By: izdeby
Differential Revision: D26273105
Pulled By: gmagogsfm
fbshipit-source-id: 934a385041137dc3731bb6fa8657b11532fed9e5
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36277
This PR introduce a flag to the tracer that guard the risky behaviors
like adding list/dict as output of the tracer. Currently to ensure not
BC breaking user, we throw warning if the tracer output is list, and
will throw error when the tracer output is dict to enforce using this
flag (next PR)
Test Plan: Imported from OSS
Differential Revision: D20998157
Pulled By: wanchaol
fbshipit-source-id: 0d2c55f1a263a48b1b92dd6ad54407815e0a6f72
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35115
This commit runs the newly added tools/clang_format.py on the JIT
codebase and includes all of the formatting changes thus produced.
Testing:
Ran the script, CI.
Test Plan: Imported from OSS
Reviewed By: eellison
Differential Revision: D20568523
Pulled By: SplitInfinity
fbshipit-source-id: e09bdb982ccf090eecfb7c7b461b8d0681eef82b
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34515
Once upon a time we thought this was necessary. In reality it is not, so
removing it.
For backcompat, our public interface (defined in `api/`) still has
typedefs to the old `script::` names.
There was only one collision: `Pass` as a `Stmt` and `Pass` as a graph
transform. I renamed one of them.
Test Plan: Imported from OSS
Differential Revision: D20353503
Pulled By: suo
fbshipit-source-id: 48bb911ce75120a8c9e0c6fb65262ef775dfba93
