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// Ensure that signaling NaN's don't cause problems while sorting
function getNaNArray(length) {
let a = [];
for (let i = 0; i < length; i++)
a.push(NaN);
return a;
}
// Test every skipNth value in some range n, where start <= n <= end
// and start/stop should be 32-bit integers with bit patterns that
// form Float32 NaNs.
function testFloat32NaNRanges(start, end) {
let skipN = 10e3;
// sample the space of possible NaNs to save time
let sampleSize = Math.floor((end - start)/ skipN);
let NaNArray = new Float32Array(getNaNArray(sampleSize));
let buffer = new ArrayBuffer(4 * sampleSize);
let uintView = new Uint32Array(buffer);
let floatView = new Float32Array(buffer);
uintView[0] = start;
for (let i = 1; i < sampleSize; i++) {
uintView[i] = uintView[0] + (i * skipN);
}
floatView.sort();
assertDeepEq(floatView, NaNArray);
}
// Test every skipNth value in some range n, where start <= n <= end
// and startHi, startLow and endHi, endLow should be 32-bit integers which,
// when combined (Hi + Low), form Float64 NaNs.
function testFloat64NaNRanges(startHi, startLow, endHi, endLow) {
// Swap on big endian platforms
if (new Uint32Array(new Uint8Array([1,2,3,4]).buffer)[0] === 0x01020304) {
[startHi, startLow] = [startLow, startHi];
[endHi, endLow] = [endLow, endHi];
}
let skipN = 10e6;
let sampleSizeHi = Math.floor((endHi - startHi)/skipN);
let sampleSizeLow = Math.floor((endLow - startLow)/skipN);
let NaNArray = new Float64Array(getNaNArray(sampleSizeHi + sampleSizeLow));
let buffer = new ArrayBuffer(8 * (sampleSizeHi + sampleSizeLow));
let uintView = new Uint32Array(buffer);
let floatView = new Float64Array(buffer);
// Fill in all of the low bits first.
for (let i = 0; i <= sampleSizeLow; i++) {
uintView[i * 2] = startLow + (i * skipN);
uintView[(i * 2) + 1] = startHi;
}
// Then the high bits.
for (let i = sampleSizeLow; i <= sampleSizeLow + sampleSizeHi; i++) {
uintView[i * 2] = endLow;
uintView[(i * 2) + 1] = startHi + ((i - sampleSizeLow) * skipN);
}
floatView.sort();
assertDeepEq(floatView, NaNArray);
}
// Float32 Signaling NaN ranges
testFloat32NaNRanges(0x7F800001, 0x7FBFFFFF);
testFloat32NaNRanges(0xFF800001, 0xFFBFFFFF);
// Float64 Signaling NaN ranges
testFloat64NaNRanges(0x7FF00000, 0x00000001, 0x7FF7FFFF, 0xFFFFFFFF);
testFloat64NaNRanges(0xFFF00000, 0x00000001, 0xFFF7FFFF, 0xFFFFFFFF);
if (typeof reportCompare === "function")
reportCompare(true, true);