🍎 Add ARM64 macOS (Apple Silicon) Support

[kengggg]

🍎 Add ARM64 macOS (Apple Silicon) Support

Overview

Implement native ARM64 macOS support for Apple Silicon users, providing optimized performance on M1/M2/M3/M4 Macs with proper cross-compilation and testing.

Tasks

1. ARM64 macOS Target Setup

• Add aarch64-apple-darwin target to CI matrix
• Configure ARM64 macOS runners (GitHub native ARM64)
• Set up cross-compilation from x86_64 to ARM64
• Test ARM64 builds on actual Apple Silicon hardware

2. Build Configuration

• Update Cargo.toml with ARM64-specific optimizations
• Configure ARM64-specific compiler flags
• Optimize for Apple Silicon performance characteristics
• Enable ARM64 NEON optimizations where applicable

3. CI Integration

• Add ARM64 macOS to build matrix
• Set up ARM64-specific testing pipeline
• Configure artifact generation for ARM64 binaries
• Add universal binary support (x86_64 + ARM64)

4. Performance Optimization

• ARM64-specific performance tuning
• Benchmark ARM64 vs x86_64 performance
• Optimize for Apple Silicon memory architecture
• Test multi-threading performance on Apple Silicon

Acceptance Criteria

• ARM64 macOS binaries build successfully in CI
• Native ARM64 performance matches or exceeds x86_64
• Universal binaries work on both Intel and Apple Silicon
• ARM64 binaries pass all tests
• Performance benchmarks validate optimization

Implementation Details

Cargo.toml Updates

[target.aarch64-apple-darwin]
rustflags = ["-C", "target-cpu=apple-m1"]

[profile.release]
lto = true
codegen-units = 1
panic = "abort"
strip = true
# ARM64-specific optimizations

CI Matrix Addition

strategy:
  matrix:
    include:
      # Existing targets...
      - os: macos-latest
        target: aarch64-apple-darwin
        arch: arm64
        rust-version: stable

Cross-compilation Setup

- name: Install ARM64 target
  run: rustup target add aarch64-apple-darwin

- name: Build ARM64 binary
  run: cargo build --release --target aarch64-apple-darwin

Universal Binary Creation

# Create universal binary combining x86_64 and ARM64
lipo -create \
  target/x86_64-apple-darwin/release/vanityssh-rust \
  target/aarch64-apple-darwin/release/vanityssh-rust \
  -output target/universal/vanityssh-rust

Testing Strategy

1. Build Testing

• Cross-compilation from x86_64 macOS
• Native compilation on ARM64 macOS runners
• Universal binary creation and validation

2. Performance Testing

• Key generation speed comparison (ARM64 vs x86_64)
• Memory usage patterns on Apple Silicon
• Multi-threading scaling on Apple Silicon cores
• Regex performance validation

3. Compatibility Testing

• macOS version compatibility (11.0+)
• Apple Silicon-specific features
• Rosetta 2 fallback testing
• Code signing validation

Expected Performance Gains

• 15-30% faster key generation on Apple Silicon
• Better power efficiency for battery-powered devices
• Native threading optimized for Apple Silicon architecture
• Memory bandwidth advantages of unified memory

Platform-Specific Considerations

• Minimum macOS: 11.0 (Big Sur) for native ARM64
• Code signing: May require developer certificates
• Notarization: For distribution outside Mac App Store
• Universal binaries: Larger file size but better compatibility

Timeline

Estimate: 3-4 days
Priority: High (Apple Silicon adoption is significant)
Phase: 2

Labels

enhancement, platform-macos, phase-2, priority-high, ci/cd, architecture

Dependencies

• Phase 1 completion (enhanced CI foundation)
• Access to ARM64 macOS runners or hardware

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Part of Phase 2: Multi-Architecture Support - Critical for Apple Silicon users