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const nativeIsLittleEndian = new Uint8Array(new Uint16Array([1]).buffer)[0] === 1;
function float32(dv, i) {
// Unbox to Int32.
i = i|0;
// Float32 addition.
let x = Math.fround(i + 0.1);
// Float32 square root.
let y = Math.fround(Math.sqrt(x));
// Store as Float16.
dv.setFloat16(0, y, nativeIsLittleEndian);
}
function float64(dv, i) {
// Unbox to Int32.
i = i|0;
// Float32 addition.
let x = Math.fround(i + 0.1);
// Float64 square root.
let y = Math.sqrt(x);
// Store as Float16.
dv.setFloat16(0, y, nativeIsLittleEndian);
}
function toBaseline(f) {
let source = f.toString();
assertEq(source.at(-1), "}");
// Add with-statement to disable Ion compilation.
source = source.slice(0, -1) + "; with ({}); }";
return Function(`return ${source};`)();
}
// Different results are expected for these inputs:
//
// Input Float64-SQRT Float32-SQRT
// -----------------------------------
// 1527 39.09375 39.0625
// 16464 128.375 128.25
// 18581 136.375 136.25
// 20826 144.375 144.25
// 23199 152.375 152.25
// 25700 160.375 160.25
// 28329 168.375 168.25
// 31086 176.375 176.25
//
// Limit execution to 1550 to avoid spending too much time on this single test.
//
// 1550 iterations should still be enough to allow tiering up to Ion, at least
// under eager compilation settings.
const LIMIT = 1550;
let float32_baseline = toBaseline(float32);
let float64_baseline = toBaseline(float64);
let dv = new DataView(new ArrayBuffer(Float16Array.BYTES_PER_ELEMENT));
let n = 0;
for (let i = 0; i < LIMIT; ++i) {
float32(dv, i);
let x = dv.getUint16(0, nativeIsLittleEndian);
float32_baseline(dv, i);
assertEq(x, dv.getUint16(0, nativeIsLittleEndian));
float64(dv, i);
let y = dv.getUint16(0, nativeIsLittleEndian);
float64_baseline(dv, i);
assertEq(y, dv.getUint16(0, nativeIsLittleEndian));
if (x !== y) {
n++;
}
}
assertEq(n, 1);