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// Return a new map, possibly filling some dummy entries to enforce creating
// multiple hash buckets.
function createMap(values, n) {
var xs = [...values];
for (var i = 0; i < n; ++i) {
xs.push({});
}
return new Map(xs.map((x, i) => [x, i]));
}
function runTest(fn) {
fn(0);
fn(100);
}
function testConstant(n) {
var xs = ["a", "b"];
var ys = ["c", "d"];
var zs = [...xs, ...ys];
var map = createMap(xs, n);
var N = 100;
var c = 0;
for (var i = 0; i < N; ++i) {
var z = zs[i & 3];
if (map.has(z)) c++;
}
assertEq(c, N / 2);
}
runTest(testConstant);
function testConstantFatInline(n) {
var xs = ["a", "b"].map(s => s.repeat(10));
var ys = ["c", "d"].map(s => s.repeat(10));
var zs = [...xs, ...ys];
var map = createMap(xs, n);
var N = 100;
var c = 0;
for (var i = 0; i < N; ++i) {
var z = zs[i & 3];
if (map.has(z)) c++;
}
assertEq(c, N / 2);
}
runTest(testConstantFatInline);
function testComputed(n) {
var xs = ["a", "b"];
var ys = ["c", "d"];
var zs = [...xs, ...ys];
var map = createMap(xs, n);
var N = 100;
var c = 0;
for (var i = 0; i < N; ++i) {
var z = zs[i & 3];
z = String.fromCharCode(z.charCodeAt(0));
if (map.has(z)) c++;
}
assertEq(c, N / 2);
}
runTest(testComputed);
function testRope(n) {
var xs = ["a", "b"];
var ys = ["c", "d"];
var zs = [...xs, ...ys];
var map = createMap(xs.map(x => x.repeat(100)), n);
var N = 100;
var c = 0;
for (var i = 0; i < N; ++i) {
var z = zs[i & 3].repeat(100);
if (map.has(z)) c++;
}
assertEq(c, N / 2);
}
runTest(testRope);