fix(l1,l2): make ARM code a bit more portable

[Oppen]

Motivation

Our previous solution to build errors on Linux ARM was a "make it work" approach
that duplicated all the assembly code. Making the variable parts into parameters
seems cleaner.

Description

• Revert "fix(l1,l2): build on ARM Linux (fix(l1,l2): build on ARM Linux #5285)";
• Use a parameter to signal which kind of object file we're creating;
• Add a macro to use the proper symbol resolution syntax based on this parameter;
• Use parameters for the exported symbols, so the name mangling always matches
  the platform.

[Copilot]

Pull Request Overview

This PR refactors the ARM assembly code for the Keccak cryptographic hash implementation to be more portable across different platforms (Linux ELF vs macOS Mach-O). Instead of maintaining duplicate assembly files for each platform, the solution uses template parameters and conditional macros to handle platform-specific differences in a single file.

Key changes:

• Consolidates duplicate ARM assembly files into a single parameterized file
• Introduces an adr macro in assembly to handle different label resolution syntax between ELF (:lo12:) and Mach-O (@PAGE/@PAGEOFF)
• Uses Rust's global_asm! template parameters to inject platform-specific symbol names

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
crates/common/crypto/keccak/mod.rs	Updates global_asm! invocation to pass parameters for ELF detection and symbol names; changes visibility of State and extern functions to pub(super)
crates/common/crypto/keccak/keccak1600-armv8.s	Adds adr macro for platform-specific label resolution; replaces hardcoded symbol names with template parameters; escapes curly braces in vector register syntax
crates/common/crypto/keccak/keccak1600-armv8-macho.s	Removes entire duplicate Mach-O specific assembly file

Comments suppressed due to low confidence (1)

crates/common/crypto/keccak/keccak1600-armv8.s:21

• [nitpick] The macro parameter {elf} is used in a .if conditional, but assembly .if directives typically expect numeric values. Since elf=const cfg!(target_os=\"linux\") as u32 passes either 0 or 1, this should work, but the comment in lines 7-9 describing the macro's purpose could be clearer about expecting a numeric value (0 for Mach-O, 1 for ELF) rather than just saying 'depending on the target OS'.

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[Copilot]

The global_asm! syntax mixes a const parameter (elf) with sym parameters, but symbols passed with sym need to match the assembly template syntax. The assembly uses {SHA3_absorb} and {SHA3_squeeze} as labels, which expects the actual symbol names (potentially with platform-specific mangling like _SHA3_absorb on macOS). However, sym SHA3_absorb provides a symbol reference that may not include the platform's name mangling. Consider verifying that Rust's sym directive properly handles the platform-specific name mangling (underscore prefix on macOS) that the assembly code expects, or explicitly handle the mangling in the template parameters.

Suggested change

	std::arch::global_asm!(include_str!("keccak1600-armv8.s"), elf=const cfg!(target_os="linux") as u32, SHA3_absorb=sym SHA3_absorb, SHA3_squeeze=sym SHA3_squeeze);
	#[cfg(target_os = "macos")]
	std::arch::global_asm!(
	include_str!("keccak1600-armv8.s"),
	elf = const cfg!(target_os = "linux") as u32,
	SHA3_absorb = const "_SHA3_absorb",
	SHA3_squeeze = const "_SHA3_squeeze"
	);
	#[cfg(all(target_arch = "aarch64", not(target_os = "macos")))]
	std::arch::global_asm!(
	include_str!("keccak1600-armv8.s"),
	elf = const cfg!(target_os = "linux") as u32,
	SHA3_absorb = const "SHA3_absorb",
	SHA3_squeeze = const "SHA3_squeeze"
	);

[github-actions]

Lines of code report

Total lines added: 2
Total lines removed: 0
Total lines changed: 2

Detailed view

+-------------------------------------------+-------+------+
| File                                      | Lines | Diff |
+-------------------------------------------+-------+------+
| ethrex/crates/common/crypto/keccak/mod.rs | 305   | +2   |
+-------------------------------------------+-------+------+