Module distance 

Distance computations with SIMD acceleration and optional GPU offload

Dispatch priority: GPU (if gpu feature) → SimSIMD (if simd feature) → scalar

Structs

FlatVectors

Flat vector storage — contiguous memory for cache-friendly access Vectors are stored as a single Vec<f32> slab: [v0_d0, v0_d1, ..., v1_d0, ...]

VisitedSet

Compact bitset for tracking visited nodes during search

Functions

inner_product

Inner product distance (negated for min-heap)

l2_squared

L2 squared distance — dispatches to best available implementation

pq_asymmetric_distance

PQ asymmetric distance from precomputed lookup table

scalar_l2_squared

Scalar L2² with 4 accumulators for ILP