[Relax][PyTorch] Add support for torch.ops.aten.sym_size.int in ExportedProgram frontend

[mshr-h]

As per title.

cc @tlopex

[gemini-code-assist]

Summary of Changes

Hello @mshr-h, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the TVM Relax frontend for PyTorch's ExportedProgram by introducing comprehensive support for the torch.ops.aten.sym_size.int operator. This ensures that PyTorch models utilizing symbolic tensor dimension queries can be accurately translated into Relax Intermediate Representation (IR), improving compatibility and the overall robustness of the frontend. The changes involve implementing a dedicated handler, integrating it into the translation pipeline, and validating its functionality with new test cases.

Highlights

• New Operator Support: Added support for the torch.ops.aten.sym_size.int operator within the TVM Relax frontend for PyTorch's ExportedProgram, enabling proper translation of models that query symbolic tensor sizes.
• Handler Implementation: A new _sym_size_int method was implemented in BaseFXGraphTranslator to extract the symbolic size of a tensor's dimension and represent it as a Relax constant.
• Frontend Integration: The _sym_size_int handler was integrated into the create_convert_map of the ExportedProgramTranslator, linking the PyTorch operator to its Relax equivalent.
• Code Refactoring: The _sym_size_int method was removed from FXTranslator, centralizing its implementation in the BaseFXGraphTranslator for better code organization.
• Test Coverage: A new test case, test_sym_size_int, was added to verify the correct translation of torch.ops.aten.sym_size.int operations into Relax IR for various dimension inputs.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request adds support for the torch.ops.aten.sym_size.int operator in the PyTorch ExportedProgram frontend. The implementation is moved to the base class BaseFXGraphImporter for better code sharing, and a new test case is added to verify the functionality. My review focuses on the robustness of the new operator implementation. I've suggested a small improvement to make the code more robust and idiomatic when handling shape expressions, which is particularly important in the context of dynamic shapes supported by ExportedProgram.