Bug 18626 – SQUIRRELFISH: support the "slow script" dialog

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Maciej Stachowiak]

SquirrelFish does not support the timeouts and callbacks that trunk uses to implement the "slow script" dialog. We'll need this to work to merge to trunk.

[Oliver Hunt]

Added for for, while, and do..while loops with
	M	JavaScriptCore/ChangeLog
	M	JavaScriptCore/VM/CodeBlock.cpp
	M	JavaScriptCore/VM/CodeGenerator.cpp
	M	JavaScriptCore/VM/CodeGenerator.h
	M	JavaScriptCore/VM/ExceptionHelpers.cpp
	M	JavaScriptCore/VM/ExceptionHelpers.h
	M	JavaScriptCore/VM/Machine.cpp
	M	JavaScriptCore/VM/Opcode.h
	M	JavaScriptCore/kjs/interpreter.cpp
	M	JavaScriptCore/kjs/nodes.cpp
	M	JavaScriptCore/kjs/object.h
Committed r33483

[Oliver Hunt]

That patch caused an epic regression on cameron's system so i rolled it out in r33484

[Oliver Hunt]

Created attachment 21200 [details]
Patch, regresses perf on some systems

[Geoffrey Garen]

Olliej also mentioned that the existing patch doesn't fix for...in.

[Geoffrey Garen]

I'm working on this now.

[Geoffrey Garen]

Oliver's patch measured as a 1.0% regression on my system.

I changed it to use a local variable, like so:

        ++count;
        if (UNLIKELY(count == THRESHOLD)) {
            exceptionValue = createInterruptedExecutionException(exec);
            goto vm_throw;
        }

(This isn't completely correct -- it's just a prototype.)

That got the regression down to 0.2%.

So, I think we could improve things by using a local variable in the common case, and only consulting the global object when the local variable reached some threshold.

[Geoffrey Garen]

Back to Oliver.

[Oliver Hunt]

Created attachment 21250 [details]
More complete version patch

This still regresses perf on some systems, but it doesn't on my system, so i can't do an further work on this :-(

[Oliver Hunt]

Created attachment 21979 [details]
Final (hopefully) patch

[Oliver Hunt]

Comment on attachment 21979 [details]
Final (hopefully) patch

Reviewed by Sam

[Oliver Hunt]

Committing to http://svn.webkit.org/repository/webkit/trunk ...
	M	JavaScriptCore/ChangeLog
	M	JavaScriptCore/JavaScriptCore.exp
	M	JavaScriptCore/VM/CodeBlock.cpp
	M	JavaScriptCore/VM/CodeGenerator.cpp
	M	JavaScriptCore/VM/ExceptionHelpers.cpp
	M	JavaScriptCore/VM/ExceptionHelpers.h
	M	JavaScriptCore/VM/LabelID.h
	M	JavaScriptCore/VM/Machine.cpp
	M	JavaScriptCore/VM/Machine.h
	M	JavaScriptCore/VM/Opcode.cpp
	M	JavaScriptCore/VM/Opcode.h
	M	JavaScriptCore/kjs/JSGlobalObject.cpp
	M	JavaScriptCore/kjs/JSGlobalObject.h
	M	JavaScriptCore/kjs/JSObject.h
	M	JavaScriptCore/kjs/interpreter.cpp
Committed r34842

[Geoffrey Garen]

Woohoo!