Function customAdder

test/features/add-custom-function.js:7–9

(a, b)

function inGPUInstanceSettings(mode) {
  function customAdder(a, b) {
    return a + b;
  }
  const gpu = new GPU({mode, functions: [customAdder] });
  const kernel = gpu.createKernel(function (a, b) {
    return customAdder(a[this.thread.x], b[this.thread.x]);