[Relax] Add FRelaxInferLayout for gather_elements operator

[guan404ming]

Why

The gather_elements operator lacked layout inference support, preventing it from participating in layout transformations during the ConvertLayout pass.

How

• Add InferLayoutGatherElements function that transforms the axis attribute according to the input layout
• Register FRelaxInferLayout attribute

[gemini-code-assist]

Summary of Changes

Hello @guan404ming, 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 Relax framework by introducing layout inference support for the "gather_elements" operator. Previously, this operator could not participate in layout transformations, limiting optimization opportunities. By adding a dedicated layout inference function and registering it, "gather_elements" can now correctly adapt to different data layouts, improving the efficiency and flexibility of Relax programs.

Highlights

• Layout Inference for gather_elements: Implemented "InferLayoutGatherElements" to enable proper layout transformation for the "gather_elements" operator, ensuring its axis attribute is correctly adjusted based on input layout.
• FRelaxInferLayout Registration: Registered the new "InferLayoutGatherElements" function under the "FRelaxInferLayout" attribute for "relax.gather_elements", integrating it into the Relax layout transformation system.
• New Test Case: Added "test_conv2d_gather_elements" to "test_transform_convert_layout.py" to validate the correct behavior of "gather_elements" with layout conversion, especially in a "conv2d" context.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

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 layout inference support for the gather_elements operator, which is a great addition for enabling layout transformations. The implementation looks mostly correct, and the new test case is a good starting point.

I've identified a potential issue in the layout selection logic in InferLayoutGatherElements that could lead to suboptimal performance in certain scenarios. I've suggested a fix to make it more robust. Additionally, I've recommended adding another test case to cover the scenario that would expose this issue, ensuring comprehensive test coverage for the new functionality.

Overall, this is a valuable contribution. Addressing the feedback will make the implementation more robust and prevent potential performance regressions.

[guan404ming]

cc @tlopex @mshr-h

[mshr-h]

Please resolve conflit. @guan404ming