Run results for: Dirty checks2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.72 Safari/537.36 Edg/90.0.818.42

Browser: Chrome 90

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
checkDirtyNumber: match	12855167.0 Ops/sec
checkDirtyNumber: nomatch	11514310.0 Ops/sec
checkDirtyBigInt: match	1589277.5 Ops/sec
checkDirtyBigInt: nomatch	1610505.2 Ops/sec
checkDirtySet: match	11262824.0 Ops/sec
checkDirtySet: nomatch	9906745.0 Ops/sec
checkDirtyProto: match	4728991.5 Ops/sec
checkDirtyProto: nomatch	4929895.0 Ops/sec
checkDirtyProto2: match	4497524.0 Ops/sec
checkDirtyProto2: nomatch	3978804.5 Ops/sec

Script Preparation code:

const dirtyNumber = 0b101;
const dirtyBigInt = 0b101n;
const dirtySet = (new Set()).add(0).add(2);

function checkDirtyNumber(bits, offset) {
    return dirtyNumber & (bits << offset);
}

function checkDirtyBigInt(bits, offset) {
    return dirtyBigInt & (BigInt(bits) << BigInt(offset));
}

function checkDirtySet(index, offset) {
    return dirtySet.has(index + offset);
}

var base = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20];
var staged = Object.create(base);
staged[1] = 101;
staged[2] = 102;
staged[10] = 110;
staged[12] = 112;
staged[15] = 115;

function checkDirtyProto(ctx, index) {
  return ctx.hasOwnProperty(index); 
}

const hasOwnProperty = Object.prototype.hasOwnProperty;

function checkDirtyProto2(ctx, index) {
  return hasOwnProperty.call(ctx, index); 
}

Tests:

checkDirtyNumber: match
checkDirtyNumber(0b1, 0);
checkDirtyNumber: nomatch
checkDirtyNumber(0b10, 0);
checkDirtyBigInt: match
checkDirtyBigInt(0b1, 0);
checkDirtyBigInt: nomatch
checkDirtyBigInt(0b10, 0);
checkDirtySet: match
checkDirtySet(0, 0);
checkDirtySet: nomatch
checkDirtySet(1, 0);
checkDirtyProto: match
checkDirtyProto(staged, 10);
checkDirtyProto: nomatch
checkDirtyProto(staged, 19);
checkDirtyProto2: match
checkDirtyProto2(staged, 10);
checkDirtyProto2: nomatch
checkDirtyProto2(staged, 19);

Run results for: Dirty checks2

checkDirtyNumber: match

checkDirtyNumber: nomatch

checkDirtyBigInt: match

checkDirtyBigInt: nomatch

checkDirtySet: match

checkDirtySet: nomatch

checkDirtyProto: match

checkDirtyProto: nomatch

checkDirtyProto2: match

checkDirtyProto2: nomatch