.NET SIMD vectorization

Produce a portable optimization that preserves the scalar contract, remains memory-safe at every length, and earns its complexity with measured results. Read the official SIMD and hardware-intrinsics guidance first and follow its comprehensive implementation templates. In particular, use its self-contained per-width dispatch, dedicated small-input handling, loop, and remainder shapes rather than reducing them to a chain of width checks. This skill supplies the decision rules and validation checks to apply while changing real code.

Inputs and prerequisites

Discover these from the repository before asking the user:

Input	Required	What to establish
Scalar implementation and tests	Yes	Existing contract, representative call sites, and supported overlap
Target frameworks and platforms	Yes	Available SIMD APIs and architectures that must behave consistently
Build and test workflow	Yes	The repository's normal commands and how to launch separate test processes
Representative workload or benchmark	For optimization	Typical input sizes and the baseline to beat

Do not add a package merely because an API exists there. First check the target framework and the project's existing dependency/versioning policy.

Core rules