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// |jit-test| skip-if: !getBuildConfiguration("moz-memory")
// 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.
// 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.
if (getBuildConfiguration("pointer-byte-size") == 4)
var s = (s32, s64) => s32
else
var s = (s32, s64) => s64
// 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(48, 56));
// Try objects with only named properties.
assertEq(tByteSize({ w: 1 }), s(32, 40));
assertEq(tByteSize({ w: 1, x: 2 }), s(32, 40));
assertEq(tByteSize({ w: 1, x: 2, y: 3 }), s(48, 56));
assertEq(tByteSize({ w: 1, x: 2, y: 3, z:4 }), s(48, 56));
assertEq(tByteSize({ w: 1, x: 2, y: 3, z:4, a: 5 }), s(80, 88));
// Try objects with only indexed properties.
assertEq(tByteSize({ 0:0 }), s(80, 88));
assertEq(tByteSize({ 0:0, 1:1 }), s(80, 88));
assertEq(tByteSize({ 0:0, 1:1, 2:2 }), s(96, 104));
assertEq(tByteSize({ 0:0, 1:1, 2:2, 3:3 }), s(96, 104));
assertEq(tByteSize({ 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 152));
// 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(80, 88));
assertEq(tByteSize({ w:1, 0:0, 1:1, 2:2 }), s(96, 104));
assertEq(tByteSize({ w:1, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 152));
assertEq(tByteSize({ w:1, x:2, y:3, 0:0 }), s(96, 104));
assertEq(tByteSize({ w:1, x:2, y:3, 0:0, 1:1, 2:2 }), s(128, 136));
assertEq(tByteSize({ w:1, x:2, y:3, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(144, 152));
assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0 }), s(128, 136));
assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0, 1:1, 2:2 }), s(128, 136));
assertEq(tByteSize({ w:1, x:2, y:3, z:4, a:6, 0:0, 1:1, 2:2, 3:3, 4:4 }), s(176, 184));
// Check various lengths of array.
assertEq(tByteSize([]), s(80, 88));
assertEq(tByteSize([1]), s(48, 56));
assertEq(tByteSize([1, 2]), s(48, 56));
assertEq(tByteSize([1, 2, 3]), s(80, 88));
assertEq(tByteSize([1, 2, 3, 4]), s(80, 88));
assertEq(tByteSize([1, 2, 3, 4, 5]), s(80, 88));
assertEq(tByteSize([1, 2, 3, 4, 5, 6]), s(80, 88));
assertEq(tByteSize([1, 2, 3, 4, 5, 6, 7]), s(112, 120));
assertEq(tByteSize([1, 2, 3, 4, 5, 6, 7, 8]), s(112, 120));
// Various forms of functions.
assertEq(tByteSize(function () {}), s(48, 56));
assertEq(tByteSize(function () {}.bind()), s(80, 88));
assertEq(tByteSize(() => 1), s(48, 56));
assertEq(tByteSize(Math.sin), s(48, 56));