Module simd 

Pure Rust SIMD kernels for SochDB vector operations.

This module provides high-performance SIMD implementations for:

• BPS Scan: L1 distance computation for Block Projection Sketches
• Int8 Dot Product: Quantized dot products for reranking
• Visibility Check: MVCC visibility bitmap generation

Architecture

The module uses a trait-based abstraction (SimdBackend) that allows swapping between architecture-specific intrinsics (core::arch) and portable SIMD (core::simd) when it stabilizes.

CPU Detection

Runtime CPU feature detection is used to select the optimal code path:

• x86_64: AVX-512 > AVX2 > SSE4.1 > Scalar
• aarch64: NEON (mandatory) + optional SVE
• Other: Scalar fallback

Safety

SIMD intrinsic functions are unsafe because they require specific CPU features. The dispatch layer handles feature detection and ensures that intrinsics are only called when the CPU supports them.

Re-exports

pub use bps_scan::bps_scan;

pub use bps_scan::bps_scan_u32;

pub use dispatch::CpuFeatures;

pub use dispatch::SimdLevel;

pub use dispatch::cpu_features;

pub use dispatch::simd_level;

pub use dot_i8::dot_i8;

pub use dot_i8::dot_i8_batch;

pub use visibility::visibility_check;

pub use visibility::visibility_check_with_txn;

Modules

bps_scan

BPS (Block Projection Sketch) L1 Distance Kernel

dispatch

Unified SIMD Dispatch Architecture

dot_i8

Int8 Dot Product Kernel

visibility

MVCC Visibility Check Kernel

Traits

SimdBackend

Trait for SIMD backend abstraction.