Bug 60111 – webkit crash opening JavaScript typed arrays matrix library benchmark

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Stephen Bannasch]

Created attachment 92183 [details]
webkit crash log

I've been maintaining a benchmark library comparing performance of a series of JavaScript libraries for doing matrix operations. Most of these libraries use JavaScript typed arrays which spun out of the WebGL standard,.

You can run the benchmarks here: http://stepheneb.github.com/webgl-matrix-benchmarks/matrix_benchmark.html

Right now when I open this page with WebKit nightly: 85595 it crashes.

These used to work in WebKit nightly ... much more slowly than in Chrome or Minefield, but they worked.

FYI: this is how fast they run on Minefield: https://img.skitch.com/20110504-qbt1ajmg948jay37nasfwhtg2a.jpg

The repository for the source code is: https://github.com/stepheneb/webgl-matrix-benchmarks

There were some recent changes -- I'll see if older versions of the matrix benchmarks worked and if a specific commit is causing the problem for WebKit nightly I'll report back here.

[Alexey Proskuryakov]

Do you happen to now when this started?

Debug mode stack trace:

Thread 0 Crashed:  Dispatch queue: com.apple.main-thread
0   com.apple.JavaScriptCore      	0x0000000100db62f5 JSC::JSValue::toBoolean(JSC::ExecState*) const + 173 (JSCell.h:290)
1   com.apple.JavaScriptCore      	0x0000000100e7765f cti_op_jtrue + 76 (JITStubs.cpp:2846)
2   com.apple.JavaScriptCore      	0x0000000100e76d2d jscGeneratedNativeCode + 0 (JITStubs.cpp:951)
3   com.apple.JavaScriptCore      	0x0000000100e58c3f JSC::JITCode::execute(JSC::RegisterFile*, JSC::ExecState*, JSC::JSGlobalData*) + 73 (JITCode.h:77)
4   com.apple.JavaScriptCore      	0x0000000100e53a98 JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 1124 (Interpreter.cpp:838)
5   com.apple.JavaScriptCore      	0x0000000100ded265 JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 167 (CallData.cpp:39)
6   com.apple.WebCore             	0x000000010246876f WebCore::JSMainThreadExecState::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 87 (JSMainThreadExecState.h:48)
7   com.apple.WebCore             	0x000000010227b20c WebCore::ScheduledAction::executeFunctionInContext(JSC::JSGlobalObject*, JSC::JSValue, WebCore::ScriptExecutionContext*) + 418 (ScheduledAction.cpp:110)
8   com.apple.WebCore             	0x000000010227b7d6 WebCore::ScheduledAction::execute(WebCore::Document*) + 294 (ScheduledAction.cpp:133)
9   com.apple.WebCore             	0x000000010227b8ac WebCore::ScheduledAction::execute(WebCore::ScriptExecutionContext*) + 84 (ScheduledAction.cpp:80)
10  com.apple.WebCore             	0x00000001019e070e WebCore::DOMTimer::fired() + 420 (DOMTimer.cpp:150)

[Geoffrey Garen]

<rdar://problem/9383724>

[Stephen Bannasch]

I don't know when it started to stop working.

I do know it worked on 4/21/11 using Webkit Nightly (84467) 

See this message: http://groups.google.com/group/cc-developers/browse_thread/thread/3c81590d3269a03d

[Stephen Bannasch]

Testing on webkit 85764 it is this commit ii my webgl-matrix-benchmarks by Gregg Tavares where webkit starts crashing:

https://github.com/stepheneb/webgl-matrix-benchmarks/commit/26f1f74783297a50c8faf555ff7919a0c865684

commit 26f1f74783297a50c8faf555ff7919a0c8656840
Author: Gregg Tavares <[e-mail]>
Date:   Tue May 3 09:12:44 2011 -0700

    Changed random matrices to use more reasonable values.
    
    The old ones used Math.random()*100 which makes really bogus
    matrices. Multiplying 99 times itself 20000 times (the count
    for the tests) overflows. The doubles turn into 'infinity'.
    So I changed them all to make a more reasonable matrix of the
    type that would be seen in a real app.

[Stephen Bannasch]

I just tested again with 85949 and the benchmark here works now:

http://stepheneb.github.com/webgl-matrix-benchmarks/matrix_benchmark.html

That's using this commit:

https://github.com/stepheneb/webgl-matrix-benchmarks/commit/6192455274e8056024d3ba8f88b1be6d7315282a

It's strange that the closure benchmarks mostly fail -- this is reported when the numerical results don't match what is expected. They pass on Chrome, FF v4.01 and Minefield Nightly.

It's also disappointing that the speed is about 6 times slower than Minefield Nightly.

[Geoffrey Garen]

> I just tested again with 85949 and the benchmark here works now:
> 
> http://stepheneb.github.com/webgl-matrix-benchmarks/matrix_benchmark.html

Sounds like this issue is fixed.