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if (typeof fdlibm === "undefined") {
var fdlibm = SpecialPowers.Cu.getJSTestingFunctions().fdlibm;
}
const f64 = new Float64Array(1);
const ui64 = new BigUint64Array(f64.buffer);
function toBits(n) {
f64[0] = n;
return ui64[0];
}
function errorInULP(actual, expected) {
// Handle NaN and +0/-0.
if (Object.is(actual, expected)) {
return 0;
}
let x = toBits(actual);
let y = toBits(expected);
return x <= y ? Number(y - x) : Number(x - y);
}
const maxExponent = Math.trunc(Math.log10(Number.MAX_VALUE));
const minExponent = Math.trunc(Math.log10(Number.MIN_VALUE));
assertEq(Math.pow(10, maxExponent + 1), Infinity);
assertEq(Math.pow(10, minExponent - 1), 0);
// Ensure the error is less than 2 ULP when compared to fdlibm.
for (let i = minExponent; i <= maxExponent; ++i) {
let actual = Math.pow(10, i);
let expected = fdlibm.pow(10, i);
let error = errorInULP(actual, expected);
assertEq(error < 2, true,
`${10} ** ${i}: ${actual} (${toBits(actual).toString(16)}) != ${expected} (${toBits(expected).toString(16)})`);
}
// Ensure the error is less than 2 ULP when compared to parsed string |1ep|.
for (let i = minExponent; i <= maxExponent; ++i) {
let actual = Math.pow(10, i);
let expected = Number("1e" + i);
let error = errorInULP(actual, expected);
assertEq(error < 2, true,
`${10} ** ${i}: ${actual} (${toBits(actual).toString(16)}) != ${expected} (${toBits(expected).toString(16)})`);
}
if (typeof reportCompare === "function")
reportCompare(true, true);