684621 - Assertion failure: copied == 0, at methodjit/FrameEntry.h:180

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

The following test asserts on mozilla-central revision a351ae35f2c4 (with shell build fix from mozilla-inbound rev fff3dc9478ce). Use options -m -n -a and a 32 bit debug build:


function runRichards() {
    queue = new Packet;
    Packet(queue, ID_DEVICE_A, KIND_DEVICE);
    new Packet;
}
var ID_DEVICE_A = 4;
var KIND_DEVICE = 0;
Packet = function (queue) {
    this.link = null
    if (queue == null) return;
    var peek, next = queue;
    while ((peek = next.link) != null)
    ID_HANDLER_B
};
runRichards()

Comment 1

[Boris Zbarsky [:bzbarsky]]

Is this a TI regression?

Comment 2

[Brian Hackett [Laid off!]]

Yes, working on a fix.

Comment 3

[Brian Hackett [Laid off!]]

After processing a loop backedge, we clear information about loop temporaries but did not uncopy any temporaries which there were copies of.  This can only happen when an assignment of a loop invariant entry occurs in the loop test.

http://hg.mozilla.org/projects/jaegermonkey/rev/1c934fd8ac88

Comment 4

[Brian Hackett [Laid off!]]

http://hg.mozilla.org/mozilla-central/rev/1c934fd8ac88

Comment 5

[Christian Holler (:decoder)]

A testcase for this bug was automatically identified at js/src/jit-test/tests/jaeger/loops/bug684621.js.