Bug 128278

Summary: <1/100 probability FTL failure: v8-v6/v8-deltablue.js.ftl-eager: Exception: TypeError: undefined is not an object (evaluating 'c.isInput')
Product: WebKit Reporter: Filip Pizlo <fpizlo>
Component: JavaScriptCoreAssignee: Filip Pizlo <fpizlo>
Status: RESOLVED FIXED    
Severity: Normal CC: barraclough, buildbot, ggaren, mark.lam, mhahnenberg, mmirman, msaboff, nrotem, oliver, rniwa, sam
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Bug Depends on:    
Bug Blocks: 112840    
Attachments:
Description Flags
the patch
mhahnenberg: review+, buildbot: commit-queue-
Archive of layout-test-results from webkit-ews-11 for mac-mountainlion-wk2 none

Description Filip Pizlo 2014-02-05 15:52:30 PST
...
Comment 1 Filip Pizlo 2014-02-09 20:50:36 PST
I can get it to repro more frequently if I increase the load on the machine.
Comment 2 Filip Pizlo 2014-02-09 21:11:58 PST
It's a FTL miscompile on chainTest#BRCzIm, which has 430 bytecode instructions.
Comment 3 Filip Pizlo 2014-02-10 00:02:59 PST
Reduced test case:


function Foo(a, b) {
    this.f = a.f;
    this.g = b.f + 1;
}

function foo(a, b) {
    return new Foo(a, b);
}

noInline(foo);

for (var i = 0; i < 100000; ++i) {
    var result = foo({f:1}, {f:2});
    if (result.f != 1)
        throw "Error: bad result.f: " + result.f;
    if (result.g != 3)
        throw "Error: bad result.g: " + result.g;
}

var result = foo({f:1}, {f:2.5});
if (result.f != 1)
    throw "Error: bad result.f: " + result.f;
if (result.g != 3.5)
    throw "Error: bad result.f: " + result.g;
Comment 4 Filip Pizlo 2014-02-10 00:22:44 PST
Created attachment 223681 [details]
the patch
Comment 5 Build Bot 2014-02-10 02:05:35 PST
Comment on attachment 223681 [details]
the patch

Attachment 223681 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.appspot.com/results/6337216930381824

New failing tests:
http/tests/misc/last-modified-parsing.html
Comment 6 Build Bot 2014-02-10 02:05:38 PST
Created attachment 223685 [details]
Archive of layout-test-results from webkit-ews-11 for mac-mountainlion-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: webkit-ews-11  Port: mac-mountainlion-wk2  Platform: Mac OS X 10.8.5
Comment 7 Mark Hahnenberg 2014-02-10 08:27:39 PST
Comment on attachment 223681 [details]
the patch

r=me
Comment 8 Filip Pizlo 2014-02-10 09:02:11 PST
Landed in http://trac.webkit.org/changeset/163789