// Check that JS::ubi::Node::size returns reasonable results for objects. // We actually hard-code specific sizes into this test, even though they're // implementation details, because in practice there are only two architecture // variants to consider (32-bit and 64-bit), and if these sizes change, that's // something SpiderMonkey hackers really want to know; they're supposed to be // stable. // Run this test only if we're using jemalloc. Other malloc implementations // exhibit surprising behaviors. For example, 32-bit Fedora builds have // non-deterministic allocation sizes. if (!getBuildConfiguration()['moz-memory']) quit(0); if (getBuildConfiguration()['pointer-byte-size'] == 4) var s = (s32, s64) => s32 else var s = (s32, s64) => s64 function tenure(obj) { gc(); return obj; } // Return the byte size of |obj|, ensuring that the size is not affected by // being tenured. (We use 'survives a GC' as an approximation for 'tenuring'.) function tByteSize(obj) { var size = byteSize(obj); minorgc(); if (size != byteSize(obj)) return 0; return size; } assertEq(tByteSize({}), s(16, 32)); // Try objects with only named properties. assertEq(tByteSize({ w: 1 }), s(32, 48)); assertEq(tByteSize({ w: 1, x: 2 }), s(32, 48)); assertEq(tByteSize({ w: 1, x: 2, y: 3 }), s(48, 64)); assertEq(tByteSize({ w: 1, x: 2, y: 3, z:4 }), s(48, 64)); assertEq(tByteSize({ w: 1, x: 2, y: 3, z:4, a: 5 }), s(80, 96)); // Try objects with only indexed properties. assertEq(tByteSize({ 0:0 }), s(96, 112)); assertEq(tByteSize({ 0:0, 1:1 }), s(96, 112)); assertEq(tByteSize({ 0:0, 1:1, 2:2 }), s(112, 128)); assertEq(tByteSize({ 0:0, 1:1, 2:2, 3:3 }), s(112, 128)); assertEq(tByteSize({ 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 160)); // Mix indexed and named properties, exploring each combination of the size // classes above. // // Oddly, the changes here as the objects grow are not simply the sums of the // changes above: for example, with one named property, the objects with three // and five indexed properties are in different size classes; but with three // named properties, there's no break there. assertEq(tByteSize({ w:1, 0:0 }), s(96, 112)); assertEq(tByteSize({ w:1, 0:0, 1:1, 2:2 }), s(112, 128)); assertEq(tByteSize({ w:1, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 160)); assertEq(tByteSize({ w:1, x:2, y:3, 0:0 }), s(112, 128)); assertEq(tByteSize({ w:1, x:2, y:3, 0:0, 1:1, 2:2 }), s(144, 160)); assertEq(tByteSize({ w:1, x:2, y:3, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 160)); assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0 }), s(144, 160)); assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0, 1:1, 2:2 }), s(144, 160)); assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(176, 192)); // Check various lengths of array. assertEq(tByteSize([]), s(80, 96)); assertEq(tByteSize([1]), s(48, 64)); assertEq(tByteSize([1, 2]), s(48, 64)); assertEq(tByteSize([1, 2, 3]), s(80, 96)); assertEq(tByteSize([1, 2, 3, 4]), s(80, 96)); assertEq(tByteSize([1, 2, 3, 4, 5]), s(80, 96)); assertEq(tByteSize([1, 2, 3, 4, 5, 6]), s(80, 96)); assertEq(tByteSize([1, 2, 3, 4, 5, 6, 7]), s(112, 128)); assertEq(tByteSize([1, 2, 3, 4, 5, 6, 7, 8]), s(112, 128)); // Various forms of functions. assertEq(tByteSize(function () {}), s(32, 64)); assertEq(tByteSize(function () {}.bind()), s(48, 80)); assertEq(tByteSize(() => 1), s(48, 80)); assertEq(tByteSize(Math.sin), s(32, 64));