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// Tests when JSOP_OPTIMIZE_SPREADCALL no longer apply after the initial Ion
// compilation.
// JSOP_OPTIMIZE_SPREADCALL can be optimised when the following conditions
// are fulfilled:
// (1) the argument is an array
// (2) the array has no hole
// (3) array[@@iterator] is not modified
// (4) the array's prototype is Array.prototype
// (5) Array.prototype[@@iterator] is not modified
// (6) %ArrayIteratorPrototype%.next is not modified
function add(a, b) {
return a + b;
}
// Array.prototype[@@iterator] was modified.
function test() {
function maybeInvalidate() {
// Use a WithStatement to prevent Ion-inlining. This ensures any
// bailouts due to type changes don't occur in this function, but
// instead in the caller.
with ({});
if (i === 1900) {
var ArrayPrototypeIterator = Array.prototype[Symbol.iterator];
Array.prototype[Symbol.iterator] = function() {
return ArrayPrototypeIterator.call([3, 4]);
};
}
}
function fn(...rest) {
maybeInvalidate();
return add(...rest);
}
for (var i = 0; i < 4000; ++i) {
assertEq(fn(1, 2), i < 1900 ? 3 : 7);
}
}
test();