function simd (simd) {
  return sharp.simd(is.bool(simd) ? simd : null);
}
Get and set use of SIMD vector unit instructions.
Requires libvips to have been compiled with highway support.

Improves the performance of `resize`, `blur` and `sharpen` operations
by taking advantage of the SIMD vector unit of the CPU, e.g. Intel SSE and ARM NEON.

@example
const simd = sharp.simd();
// simd is `true` if the runtime use of highway is currently enabled
@example
const simd = sharp.simd(false);
// prevent libvips from using highway at runtime

@param {boolean} [simd=true]
@returns {boolean}