[PERF] Build High-Speed Byte Swapping Utility in Yul

[mijinummi]

Labels: medium-difficulty, yul, math, gasguard
Difficulty: Medium
Module: contracts/utils/

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🧠 Concept

Develop a Yul utility to reverse endianness (byte-swap) for 256-bit words (bytes32 or uint256) using optimized bit shift masks.

⚠️ Problem

Reversing byte order in high-level Solidity using loops requires multiple allocations and memory shifts, creating excessive loop overhead.

📁 Implementation Scope

• contracts/utils/YulByteSwapper.sol
• test/utils/YulByteSwapper.test.ts

🛠️ Requirements

1. Implement endianness reversal logic using inline Yul assembly with optimized bitwise operations (SHR, SHL, AND, OR).
2. Support full 32-byte word endianness conversion without memory buffer allocation.

🎯 Acceptance Criteria

• Reverses byte order in a single $O(1)$ assembly step.
• Verified accurately against high-level endian conversion outputs.

[EstherIkechukwu]

I have gone through the description expect a pr in less than 12hrs

[rabsqueen]

Hi, can I work on this?

[grantfox-oss]

🦊 GrantFox — @rabsqueen has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #748)
2. Your PR will be reviewed by the MDTechLabs maintainers

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[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Third Campaign campaign!

@rabsqueen's PR #760 was approved and merged by @mijinummi.

🏆 @rabsqueen: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (621 total points). Track your full progress on GrantFox.

👏 Great work, @rabsqueen! Keep contributing to MDTechLabs.