Update exir_deserialize logic

[ethansfng]

Differential Revision: D87112636

[pytorch-bot]

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[meta-codesync]

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[Copilot]

Pull Request Overview

This PR fixes a bug in the metadata_split function used during deserialization of nn_module_stack metadata. The old implementation incorrectly removed parentheses and their content before splitting, which failed when paths contained nested getattr() calls (e.g., getattr(getattr(L['self'].layers, '0'), '3')). The new implementation properly handles nested parentheses and brackets by tracking depth while parsing.

Key Changes

• Replaced regex-based splitting logic with a depth-tracking parser that correctly handles nested parentheses/brackets
• Updated comment to reflect the new approach for handling nested structures
• Preserved the requirement that metadata must split into exactly 3 parts (key, path, type)

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[mergennachin]

@ethansfng Please see the copilot recommendations, they look pretty good

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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