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// |jit-test| test-also=--no-sse4
// Return the next Number value in direction to +Infinity.
function nextUp(num) {
if (!Number.isFinite(num)) {
return num;
}
if (num === 0) {
return Number.MIN_VALUE;
}
let f64 = new Float64Array([num]);
let u64 = new BigUint64Array(f64.buffer);
u64[0] += (num < 0 ? -1n : 1n);
return f64[0];
}
// Return the next Number value in direction to -Infinity.
function nextDown(num) {
if (!Number.isFinite(num)) {
return num;
}
if (num === 0) {
return -Number.MIN_VALUE;
}
let f64 = new Float64Array([num]);
let u64 = new BigUint64Array(f64.buffer);
u64[0] += (num < 0 ? 1n : -1n);
return f64[0];
}
function Clamped(num) {
let uint8Clamped = new Uint8ClampedArray(1);
// Note: Assignment to ensure JIT code path for ClampDoubleToUint8.
uint8Clamped[0] = num;
return uint8Clamped[0];
}
Math.clamp = (v, min, max) => Math.min(Math.max(v, min), max);
// Test numbers around integer inputs.
for (let i = -1; i <= 255 + 1; ++i) {
let num = i;
assertEq(Clamped(num), Math.clamp(i, 0, 255));
let down = num;
for (let j = 0; j < 10; ++j) {
down = nextDown(down);
assertEq(Clamped(down), Math.clamp(i, 0, 255));
}
let up = num;
for (let j = 0; j < 10; ++j) {
up = nextUp(up);
assertEq(Clamped(up), Math.clamp(i, 0, 255));
}
}
// Test numbers around the half-way case.
for (let i = -1; i <= 255 + 1; ++i) {
let num = i + 0.5;
assertEq(Clamped(num), Math.clamp(i + (i & 1), 0, 255));
let down = num;
for (let j = 0; j < 10; ++j) {
down = nextDown(down);
assertEq(Clamped(down), Math.clamp(i, 0, 255));
}
let up = num;
for (let j = 0; j < 10; ++j) {
up = nextUp(up);
assertEq(Clamped(up), Math.clamp(i + 1, 0, 255));
}
}