v8/test/mjsunit/harmony/atomics.js
Shu-yu Guo 6962221295 [atomics] Relax Atomics methods to work on ArrayBuffers
This reached consensus in the March 2020 TC39.
https://github.com/tc39/ecma262/pull/1908

This aligns JS with wasm, which allows atomics operations on non-shared
linear memory.

Bug: v8:10687, v8:9921
Change-Id: I7b60473b271cee6bccb342e97a4fd3781aedddb4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2330802
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69392}
2020-08-13 22:10:07 +00:00

630 lines
22 KiB
JavaScript

// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --harmony-sharedarraybuffer
//
function toRangeWrapper(is_big) {
return function _toRangeWrapped(raw_value) {
var raw_range = this.max - this.min + (is_big ? 1n : 1);
let range = is_big ? BigInt(raw_range) : raw_range;
let value = is_big ? BigInt(raw_value) : raw_value;
while (value < this.min) {
value += range;
}
while (value > this.max) {
value -= range;
}
return value;
}
}
function makeConstructorObject(constr, min, max, toRange) {
var o = {constr: constr, min: min, max: max};
let is_big = constr.name.startsWith('Big')
o.toRange = toRangeWrapper(is_big).bind(o);
return o;
}
function IsBig(t) {
return t.constructor.name.startsWith('Big');
}
function MaybeIntToBigInt(arr, i) {
if (IsBig(arr)) {
return BigInt(i);
} else {
return i;
}
}
var IntegerTypedArrayConstructors = [
makeConstructorObject(Int8Array, -128, 127),
makeConstructorObject(Int16Array, -32768, 32767),
makeConstructorObject(Int32Array, -0x80000000, 0x7fffffff),
makeConstructorObject(BigInt64Array, -0x8000_0000_0000_0000n,
0x7fff_ffff_ffff_ffffn),
makeConstructorObject(BigUint64Array, 0n, 0xffff_ffff_ffff_ffffn),
makeConstructorObject(Uint8Array, 0, 255),
makeConstructorObject(Uint16Array, 0, 65535),
makeConstructorObject(Uint32Array, 0, 0xffffffff),
];
(function TestBadArray() {
var ab = new ArrayBuffer(16);
var sab = new SharedArrayBuffer(128);
var sf32a = new Float32Array(sab);
var sf64a = new Float64Array(sab);
var u8ca = new Uint8ClampedArray(sab);
// Atomic ops required integer typed arrays
var badArrayTypes = [
undefined, 1, 'hi', 3.4, ab, sab, sf32a, sf64a, u8ca
];
badArrayTypes.forEach(function(o) {
assertThrows(function() { Atomics.compareExchange(o, 0, 0, 0); },
TypeError);
assertThrows(function() { Atomics.load(o, 0); }, TypeError);
assertThrows(function() { Atomics.store(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.add(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.sub(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.and(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.or(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.xor(o, 0, 0); }, TypeError);
assertThrows(function() { Atomics.exchange(o, 0, 0); }, TypeError);
});
})();
(function TestBadIndex() {
var sab = new SharedArrayBuffer(8);
var si32a = new Int32Array(sab);
var si32a2 = new Int32Array(sab, 4);
// Indexes that are out of bounds when coerced via ToIndex should throw
// RangeError.
[-Infinity, Infinity].forEach(function(i) {
assertThrows(function() { Atomics.compareExchange(si32a, i, 0); },
RangeError);
assertThrows(function() { Atomics.load(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.store(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.add(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.sub(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.and(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.or(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.xor(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.exchange(si32a, i, 0); }, RangeError);
}, RangeError);
// Out-of-bounds indexes should throw RangeError.
[-1, 2, 100].forEach(function(i) {
assertThrows(function() { Atomics.compareExchange(si32a, i, 0, 0); },
RangeError);
assertThrows(function() { Atomics.load(si32a, i); }, RangeError);
assertThrows(function() { Atomics.store(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.add(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.sub(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.and(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.or(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.xor(si32a, i, 0); }, RangeError);
assertThrows(function() { Atomics.exchange(si32a, i, 0); }, RangeError);
}, RangeError);
// Out-of-bounds indexes for array with offset should throw RangeError.
[-1, 1, 100].forEach(function(i) {
assertThrows(function() { Atomics.compareExchange(si32a2, i, 0, 0); });
assertThrows(function() { Atomics.load(si32a2, i); }, RangeError);
assertThrows(function() { Atomics.store(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.add(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.sub(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.and(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.or(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.xor(si32a2, i, 0); }, RangeError);
assertThrows(function() { Atomics.exchange(si32a2, i, 0); }, RangeError);
});
// Monkey-patch length and make sure these functions still throw.
Object.defineProperty(si32a, 'length', {get: function() { return 1000; }});
[2, 100].forEach(function(i) {
assertThrows(function() { Atomics.compareExchange(si32a, i, 0, 0); });
assertThrows(function() { Atomics.load(si32a, i); });
assertThrows(function() { Atomics.store(si32a, i, 0); });
assertThrows(function() { Atomics.add(si32a, i, 0); });
assertThrows(function() { Atomics.sub(si32a, i, 0); });
assertThrows(function() { Atomics.and(si32a, i, 0); });
assertThrows(function() { Atomics.or(si32a, i, 0); });
assertThrows(function() { Atomics.xor(si32a, i, 0); });
assertThrows(function() { Atomics.exchange(si32a, i, 0); });
});
})();
(function TestGoodIndex() {
var sab = new SharedArrayBuffer(64);
var si32a = new Int32Array(sab);
var si32a2 = new Int32Array(sab, 32);
var testOp = function(op, ia, index, expectedIndex, name) {
for (var i = 0; i < ia.length; ++i)
ia[i] = i * 2;
ia[expectedIndex] = 0;
var result = op(ia, index, 0, 0);
assertEquals(0, result, name);
assertEquals(0, ia[expectedIndex], name);
for (var i = 0; i < ia.length; ++i) {
if (i == expectedIndex) continue;
assertEquals(i * 2, ia[i], name);
}
};
// These values all map to index 0
[-0, 0, 0.0, null, false, NaN, {}, '0.2', 'hi', undefined].forEach(
function(i) {
var name = String(i);
[si32a, si32a2].forEach(function(array) {
testOp(Atomics.compareExchange, array, i, 0, name);
testOp(Atomics.load, array, i, 0, name);
testOp(Atomics.store, array, i, 0, name);
testOp(Atomics.add, array, i, 0, name);
testOp(Atomics.sub, array, i, 0, name);
testOp(Atomics.and, array, i, 0, name);
testOp(Atomics.or, array, i, 0, name);
testOp(Atomics.xor, array, i, 0, name);
testOp(Atomics.exchange, array, i, 0, name);
});
});
// These values all map to index 3
var valueOf = {valueOf: function(){ return 3;}};
var toString = {toString: function(){ return '3';}};
[3, 3.0, '3', '3.0', valueOf, toString].forEach(function(i) {
var name = String(i);
[si32a, si32a2].forEach(function(array) {
testOp(Atomics.compareExchange, array, i, 3, name);
testOp(Atomics.load, array, i, 3, name);
testOp(Atomics.store, array, i, 3, name);
testOp(Atomics.add, array, i, 3, name);
testOp(Atomics.sub, array, i, 3, name);
testOp(Atomics.and, array, i, 3, name);
testOp(Atomics.or, array, i, 3, name);
testOp(Atomics.xor, array, i, 3, name);
testOp(Atomics.exchange, array, i, 3, name);
});
});
})();
function clearArray(sab) {
var ui8 = new Uint8Array(sab);
for (var i = 0; i < sab.byteLength; ++i) {
ui8[i] = 0;
}
}
(function TestCompareExchange() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
// array[i] == 0, CAS will store
assertEquals(_i(0), Atomics.compareExchange(array, i, _i(0), _i(50)),
name);
assertEquals(_i(50), array[i], name);
// array[i] == 50, CAS will not store
assertEquals(_i(50), Atomics.compareExchange(array, i, _i(0), _i(100)),
name);
assertEquals(_i(50), array[i], name);
}
})
});
})();
(function TestLoad() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(0);
assertEquals(_i(0), Atomics.load(array, i), name);
array[i] = _i(50);
assertEquals(_i(50), Atomics.load(array, i), name);
}
})
});
// Test Smi range
(function () {
var sab = new SharedArrayBuffer(4);
var i32 = new Int32Array(sab);
var u32 = new Uint32Array(sab);
function testLoad(signedValue, unsignedValue) {
u32[0] = unsignedValue;
assertEquals(unsignedValue, Atomics.load(u32, 0));
assertEquals(signedValue, Atomics.load(i32, 0));
}
testLoad(0x3fffffff, 0x3fffffff); // 2**30-1 (always smi)
testLoad(0x40000000, 0x40000000); // 2**30 (smi if signed and 32-bits)
testLoad(0x80000000, -0x80000000); // 2**31 (smi if signed and 32-bits)
testLoad(0xffffffff, -1); // 2**31 (smi if signed)
});
})();
(function TestStore() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
assertEquals(_i(50), Atomics.store(array, i, _i(50)), name);
assertEquals(_i(50), array[i], name);
assertEquals(_i(100), Atomics.store(array, i, _i(100)), name);
assertEquals(_i(100), array[i], name);
}
})
});
})();
(function TestAdd() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
assertEquals(_i(0), Atomics.add(array, i, _i(50)), name);
assertEquals(_i(50), array[i], name);
assertEquals(_i(50), Atomics.add(array, i, _i(70)), name);
assertEquals(_i(120), array[i], name);
}
})
});
})();
(function TestSub() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(120);
assertEquals(_i(120), Atomics.sub(array, i, _i(50)), name);
assertEquals(_i(70), array[i], name);
assertEquals(_i(70), Atomics.sub(array, i, _i(70)), name);
assertEquals(_i(0), array[i], name);
}
})
});
})();
(function TestAnd() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(sta);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(0x3f);
assertEquals(_i(0x3f), Atomics.and(array, i, _i(0x30)), name);
assertEquals(_i(0x30), array[i], name);
assertEquals(_i(0x30), Atomics.and(array, i, _i(0x20)), name);
assertEquals(_i(0x20), array[i], name);
}
})
});
})();
(function TestOr() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(0x30);
assertEquals(_i(0x30), Atomics.or(array, i, _i(0x1c)), name);
assertEquals(_i(0x3c), array[i], name);
assertEquals(_i(0x3c), Atomics.or(array, i, _i(0x09)), name);
assertEquals(_i(0x3d), array[i], name);
}
})
});
})();
(function TestXor() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(0x30);
assertEquals(_i(0x30), Atomics.xor(array, i, _i(0x1c)), name);
assertEquals(_i(0x2c), array[i], name);
assertEquals(_i(0x2c), Atomics.xor(array, i, _i(0x09)), name);
assertEquals(_i(0x25), array[i], name);
}
})
});
})();
(function TestExchange() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var sta2 = new t.constr(sab, 5 * t.constr.BYTES_PER_ELEMENT);
[sta, sta2].forEach(function(array) {
let _i = (i) => { return MaybeIntToBigInt(array, i); }
clearArray(array.buffer);
var name = Object.prototype.toString.call(array);
for (var i = 0; i < array.length; ++i) {
array[i] = _i(0x30);
assertEquals(_i(0x30), Atomics.exchange(array, i, _i(0x1c)), name);
assertEquals(_i(0x1c), array[i], name);
assertEquals(_i(0x1c), Atomics.exchange(array, i, _i(0x09)), name);
assertEquals(_i(0x09), array[i], name);
}
})
});
})();
(function TestIsLockFree() {
// Various invalid cases.
var valueOf = {valueOf: function(){ return 3;}};
var toString = {toString: function(){ return '3';}};
var invalid = [3.14, 'foo', Infinity, NaN, false, undefined, valueOf,
toString];
invalid.forEach(function(v) {
assertEquals(false, Atomics.isLockFree(v), JSON.stringify(v));
});
// For all platforms we support, 1, 2 and 4 bytes should be lock-free.
assertTrue(Atomics.isLockFree(1));
assertTrue(Atomics.isLockFree(2));
assertTrue(Atomics.isLockFree(4));
assertFalse(Atomics.isLockFree(0));
assertFalse(Atomics.isLockFree(3));
assertFalse(Atomics.isLockFree(5));
assertFalse(Atomics.isLockFree(6));
assertFalse(Atomics.isLockFree(7));
// isLockFree(8) is platform dependent.
for (var i = 9; i < 100; ++i) assertFalse(Atomics.isLockFree(i));
})();
(function TestToNumber() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(1 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
let _i = (i) => { return MaybeIntToBigInt(sta, i); }
var valueOf = {valueOf: function(){ return _i(3);}};
var toString = {toString: function(){ return '3';}};
[false, true, undefined, valueOf, toString].forEach(function(v) {
if (v === undefined && IsBig(sta)) {
// undefined does not convert to a BigInt.
return;
}
let _v = () => { return IsBig(sta) ? _i(v) : (v|0); }
var name = Object.prototype.toString.call(sta) + ' - ' + v;
// CompareExchange
sta[0] = _i(50);
assertEquals(_i(50), Atomics.compareExchange(sta, 0, v, v), name);
// Store
assertEquals(_v(), Atomics.store(sta, 0, v), name);
assertEquals(_v(), sta[0], name);
// Add
sta[0] = _i(120);
assertEquals(_i(120), Atomics.add(sta, 0, v), name);
assertEquals(_i(120) + _v(), sta[0], name);
// Sub
sta[0] = _i(70);
assertEquals(_i(70), Atomics.sub(sta, 0, v), name);
assertEquals(_i(70) - _v(), sta[0]);
// And
sta[0] = _i(0x20);
assertEquals(_i(0x20), Atomics.and(sta, 0, v), name);
assertEquals(_i(0x20) & _v(), sta[0]);
// Or
sta[0] = _i(0x3d);
assertEquals(_i(0x3d), Atomics.or(sta, 0, v), name);
assertEquals(_i(0x3d) | _v(), sta[0]);
// Xor
sta[0] = _i(0x25);
assertEquals(_i(0x25), Atomics.xor(sta, 0, v), name);
assertEquals(_i(0x25) ^ _v(), sta[0]);
// Exchange
sta[0] = _i(0x09);
assertEquals(_i(0x09), Atomics.exchange(sta, 0, v), name);
assertEquals(_v(), sta[0]);
});
});
})();
(function TestWrapping() {
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var name = Object.prototype.toString.call(sta);
let _i = (i) => { return MaybeIntToBigInt(sta, i); }
var range = t.max - t.min + _i(1);
var offset;
var operand;
var val, newVal;
var valWrapped, newValWrapped;
for (offset = -range; offset <= range; offset += range) {
// CompareExchange
sta[0] = val = _i(0);
newVal = val + offset + _i(1);
newValWrapped = t.toRange(newVal);
assertEquals(val, Atomics.compareExchange(sta, 0, val, newVal), name);
assertEquals(newValWrapped, sta[0], name);
sta[0] = val = t.min;
newVal = val + offset - _i(1);
newValWrapped = t.toRange(newVal);
assertEquals(val, Atomics.compareExchange(sta, 0, val, newVal), name);
assertEquals(newValWrapped, sta[0], name);
// Store
sta[0] = _i(0);
val = t.max + offset + _i(1);
valWrapped = t.toRange(val);
assertEquals(val, Atomics.store(sta, 0, val), name);
assertEquals(valWrapped, sta[0], name);
sta[0] = val = t.min + offset - _i(1);
valWrapped = t.toRange(val);
assertEquals(val, Atomics.store(sta, 0, val), name);
assertEquals(valWrapped, sta[0], name);
// Add
sta[0] = val = t.max;
operand = offset + _i(1);
valWrapped = t.toRange(val + operand);
assertEquals(val, Atomics.add(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
sta[0] = val = t.min;
operand = offset - _i(1);
valWrapped = t.toRange(val + operand);
assertEquals(val, Atomics.add(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
// Sub
sta[0] = val = t.max;
operand = offset - _i(1);
valWrapped = t.toRange(val - operand);
assertEquals(val, Atomics.sub(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
sta[0] = val = t.min;
operand = offset + _i(1);
valWrapped = t.toRange(val - operand);
assertEquals(val, Atomics.sub(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
// There's no way to wrap results with logical operators, just test that
// using an out-of-range value is properly wrapped/clamped when written
// to memory.
// And
sta[0] = val = _i(0xf);
operand = _i(0x3) + offset;
valWrapped = t.toRange(val & operand);
assertEquals(val, Atomics.and(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
// Or
sta[0] = val = _i(0x12);
operand = _i(0x22) + offset;
valWrapped = t.toRange(val | operand);
assertEquals(val, Atomics.or(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
// Xor
sta[0] = val = _i(0x12);
operand = _i(0x22) + offset;
valWrapped = t.toRange(val ^ operand);
assertEquals(val, Atomics.xor(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
// Exchange
sta[0] = val = _i(0x12);
operand = _i(0x22) + offset;
valWrapped = t.toRange(operand);
assertEquals(val, Atomics.exchange(sta, 0, operand), name);
assertEquals(valWrapped, sta[0], name);
}
});
})();
(function TestValidateIndexBeforeValue() {
var testOp = function(op, sta, name) {
var valueof_has_been_called = 0;
var value = {valueOf: function() { valueof_has_been_called = 1; return 0;}};
var index = -1;
// The index should be checked before calling ToInteger on the value, so
// valueof_has_been_called should not be modified.
sta[0] = MaybeIntToBigInt(sta, 0);
assertThrows(function() { op(sta, index, value, value); }, RangeError);
assertEquals(0, valueof_has_been_called);
};
IntegerTypedArrayConstructors.forEach(function(t) {
var sab = new SharedArrayBuffer(10 * t.constr.BYTES_PER_ELEMENT);
var sta = new t.constr(sab);
var name = Object.prototype.toString.call(sta);
testOp(Atomics.compareExchange, sta, name);
testOp(Atomics.load, sta, name);
testOp(Atomics.store, sta, name);
testOp(Atomics.add, sta, name);
testOp(Atomics.sub, sta, name);
testOp(Atomics.and, sta, name);
testOp(Atomics.or, sta, name);
testOp(Atomics.xor, sta, name);
testOp(Atomics.exchange, sta, name);
});
})();