Run results for: Function call vs array access

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:89.0) Gecko/20100101 Firefox/89.0

Browser: Firefox 89

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Array access	118137.5 Ops/sec
Function access	20535.8 Ops/sec

Script Preparation code:

var memory = new ArrayBuffer(1024 * 1024);
var memoryF32 = new Float32Array(memory);
var memoryU32 = new Uint32Array(memory);

Tests:

Array access
for (let i = 0; i < 1024; ++i) { memoryF32[i] = Math.random(); } for (let i = 1; i < 1024; ++i) { memoryF32[i-1] = memoryF32[i] * 2; } for (let i = 1; i < 1024; ++i) { memoryU32[i + 1024] = memoryF32[i] > 0.5 ? 1 : 0; }
Function access
const readF32 = (idx) => memoryF32[idx]; const writeF32 = (idx, value) => memoryF32[idx] = value; const writeU32 = (idx, value) => memoryU32[idx+1024] = value; for (let i = 0; i < 1024; ++i) { writeF32(i, Math.random()); } for (let i = 1; i < 1024; ++i) { writeF32(i-1, readF32(i) * 2); } for (let i = 1; i < 1024; ++i) { writeU32(i, memoryF32[i] > 0.5 ? 1 : 0); }