Improve performance around code ranges and add tests

[mr-tz]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello @mr-tz, 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 focuses on optimizing the handling and querying of code and relocation ranges within the application. By introducing a specialized data structure for managing offset ranges and refactoring the logic that uses these ranges, the changes aim to improve performance and maintainability. The modifications are thoroughly tested with new unit and integration tests to ensure correctness and stability.

Highlights

• Performance Improvement: Introduced a new OffsetRanges class to efficiently store and query ranges of integer offsets, replacing less performant Set lookups for code and relocation ranges.
• Code Refactoring: Updated check_is_reloc and check_is_code functions to utilize the new OffsetRanges.overlaps method, significantly optimizing checks for whether a string falls within code or relocation sections. The PELayout class now uses OffsetRanges for its reloc_offsets and code_offsets attributes.
• Enhanced Code Range Processing: Refactored the compute_pe_layout function to leverage new helper functions (_merge_overlapping_ranges and _get_code_ranges) for more robust and efficient extraction and merging of code ranges from PE files.
• Comprehensive Testing: Added extensive unit tests for the new OffsetRanges class and the code range utility functions (_merge_overlapping_ranges, _get_code_ranges). A new integration test for a PE file (pma0101.dll_) was also added to validate the end-to-end string extraction and tagging process with the updated range logic.

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[gemini-code-assist]

Code Review

This pull request introduces a significant performance improvement by replacing the use of Set[int] with a new OffsetRanges class for handling code and relocation offsets. The new class intelligently merges individual offsets into contiguous ranges and uses binary search for fast overlap checks. This is a great optimization. The changes are well-supported by a comprehensive suite of new unit and integration tests, which is excellent.

I've left a few comments with suggestions for minor improvements, mainly related to code clarity and cleaning up some test code. Overall, this is a high-quality contribution.