Run results for: Pre-calc with bit shift vs Typical Code

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 18

Operating system: iOS 18.0

Device Platform: Mobile

Date tested: one year ago

Bit-shift

1.7M/s

Typical Code

1.3M/s

View exact numbers

Test name	Executions per second
✓ Bit-shift	1,732,555 Ops/sec
Typical Code	1,295,169 Ops/sec

Script Preparation code:

var cases = [
  { nx: undefined, ny: 12 },
  { ny: 12, nx: undefined },
  { nx: undefined, ny: undefined },
  { nx: 12, ny: 12 }
]
var style = { transform: null }

Tests:

Typical Code
for (const {nx, ny} of cases) { if (nx !== undefined || ny !== undefined) { style.transform = nx !== undefined ? (ny !== undefined ? `translate(${nx}px, ${ny}px)` : `translateX(${nx}px)`) : `translateY(${ny}px)`; } }
Bit-shift
for (const {nx, ny} of cases) { const sx = nx !== undefined // state_x const sy = ny !== undefined // state_y const state = (sx && ! sy ? 1 : 0) | (sy && ! sx ? 2 : 0) | (sx && sy ? 4 : 0) | ( ! sx || ! sy ? 8 : 0) switch (state) { case 8: // neither style.transform = '' break case 4: // both style.transform = `translate(${nx}px, ${ny}px)` break case 2: // only y style.transform = `translateY(${ny}px)` break case 1: // only x style.transform = `translateX(${nx}px)` break; } }