Run results for: DataView or BitTwiddling, Aligned and Unaligned

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36

Browser: Chrome 116

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Bit Twiddling, Aligned	1213331.0 Ops/sec
DataView, Aligned	4665979.0 Ops/sec
BitTwiddling, Unaligned	1206346.1 Ops/sec
DataView, Unaligned	4622813.5 Ops/sec

Script Preparation code:

let buf = new ArrayBuffer(12);
u32s = new Uint32Array(buf);
u8s = new Uint8Array(buf);
dv = new DataView(buf);
offsetAligned = 0;
offsetUnaligned = 1;
value = 0x01020304;

Tests:

Bit Twiddling, Aligned
u8s[offsetAligned + 0] = value >> 24; u8s[offsetAligned + 1] = value >> 16; u8s[offsetAligned + 2] = value >> 8; u8s[offsetAligned + 3] = value;
DataView, Aligned
dv.setInt32(offsetAligned, value, false)
BitTwiddling, Unaligned
u8s[offsetUnaligned + 0] = value >> 24; u8s[offsetUnaligned + 1] = value >> 16; u8s[offsetUnaligned + 2] = value >> 8; u8s[offsetUnaligned + 3] = value;
DataView, Unaligned
dv.setInt32(offsetUnaligned, value, false)

Run results for: DataView or BitTwiddling, Aligned and Unaligned

Is DataView faster than directly bit twiddling?

Bit Twiddling, Aligned

DataView, Aligned

BitTwiddling, Unaligned

DataView, Unaligned