November 2012 - squirrelfish-dev - lists.macosforge.org

[webkit-help] [squirrelfish-dev] JIT Optimize Property Access failed
by talking1239＠gmail.com 05 Mar '13

05 Mar '13

Hi I enable ENABLE_JIT_OPTIMIZE_PROPERTY_ACCESS feature and find that it will crash when go back the home page after run follow test case, I think it is caused by the optimize propery access, so anyone know that it is caused by the arch related code or jit Infrastructure code? and if i disable ENABLE_JIT_OPTIMIZE_PROPERTY_ACCESS feature, it will run correctly. Any help explaining this would be much appreciated! test case: var Origin = new Object(); function Init() { Origin.V = [150] } for ( var i = 20; i <= 160; i *= 2 ) { //Init(i); } Init(); Init(); Init(); Origin = null; Callstack: JAVASCRIPTCORE!const JSC::JSArray::`vftable' + 2 bytes JAVASCRIPTCORE!JSC::Heap::sweep() line 1104 + 14 bytes JAVASCRIPTCORE!JSC::Heap::collectAllGarbage() line 1306 WEBKIT!WebCore::collect(void * 0x00000000) line 47 WEBKIT!WebCore::GCController::gcTimerFired(WebCore::Timer<WebCore::GCController> * 0x06a905a0 {m_object=??? m_function=??? }) line 70 WEBKIT!WebCore::Timer<WebCore::PageCache>::fired() line 98 + 20 bytes WEBKIT!WebCore::ThreadTimers::sharedTimerFiredInternal() line 115 WEBKIT!WebCore::ThreadTimers::sharedTimerFired() line 91 -- BGs/Felix Shi -- BGs/Felix Shi

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Dumping jit with corresponding js source.
by eminemence＠gmail.com 27 Nov '12

27 Nov '12

Hi , Is there an existing feature to dump the generated jit with the corresponding js source code. It would be useful to understand how much jit is generated for each js statement? Also is there any in-built profiler in sfx? Thanks, Mayur Kankanwadi.

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Re: [squirrelfish] [webkit-dev] Fwd: Understending LLInt
by wingoog moon 20 Nov '12

20 Nov '12

Sorry I just had a mistake, it is interprets code. but my question is how it actually does interpretation. In generateThunkWithJumpTo function there are 2 lines which I think actually start LLInt. jit.move(JSInterfaceJIT::TrustedImmPtr(bitwise_cast<void*>(target)), JSInterfaceJIT::regT0); jit.jump(JSInterfaceJIT::regT0); If I'm not mistaken this to lines do some preparations And actual interpretation begins only after JSValue result = JSValue::decode(ctiTrampoline(m_ref.code().executableAddress(), registerFile, callFrame, 0, 0, globalData)) in JITCode.h. Am I right? Thanks for attention! On Wed, Nov 14, 2012 at 8:11 PM, Filip Pizlo <fpizlo(a)apple.com> wrote: > The LLInt doesn't compile anything to native code, since its an > interpreter. It interprets the code instead. > > -Filip > > On Nov 14, 2012, at 3:19 AM, wingoog moon <wingoog91(a)gmail.com> wrote: > > > > ---------- Forwarded message ---------- > From: wingoog moon <wingoog91(a)gmail.com> > Date: Wed, Nov 14, 2012 at 1:51 AM > Subject: Understending LLInt > To: squirrelfish-dev(a)lists.webkit.org > > > Hi All. > > At which point LLInt starts to compile bytecode to the native code? > If I'm not mistaken it should be in prepareForExecution function, so I > guess that this part of code actually does translation from bytecode to > native code. > > if (JITCode::isBaselineCode(jitType)) { > // Start off in the low level interpreter. > LLInt::getEntrypoint(exec->globalData(), codeBlock.get(), jitCode); > codeBlock->setJITCode(jitCode, MacroAssemblerCodePtr()); > return true; > } > > But I just cannot figure out how translation actually is done. My only > assumption that this function only set up some native code, and actually > compilation begins when calling functions from native assembly code. > > Can anyone please explain LLInt working mechanism, any links or articles? > > > _______________________________________________ > webkit-dev mailing list > webkit-dev(a)lists.webkit.org > http://lists.webkit.org/mailman/listinfo/webkit-dev > >

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Understending LLInt
by wingoog moon 13 Nov '12

13 Nov '12

Hi All. At which point LLInt starts to compile bytecode to the native code. If I'm not mistaken it should be in prepareForExecution function, so I guess that this part of code actually does translation from bytecode to native code. if (JITCode::isBaselineCode(jitType)) { // Start off in the low level interpreter. LLInt::getEntrypoint(exec->globalData(), codeBlock.get(), jitCode); codeBlock->setJITCode(jitCode, MacroAssemblerCodePtr()); return true; } But I just cannot figure out how translation actually is done. My only assumption that this function only set up some native code, and actually compilation begins from calling functions from native assembly code. Can anyone please explain LLInt working mechanism, any links or articles?

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Help
by Leonard Euler 13 Nov '12

13 Nov '12

Hi. I know that assembly of globalCode generated in Interpreter.cpp:line 877,but I am can't find a concrete part of code where generated assembly.Please help me.

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help me
by Leonard Euler 12 Nov '12

12 Nov '12

I am a novice programmer and at work gave me the following problem: find a place in the code where interpretr decides that should work DFG-JIT. I searched this part of code 2 weeks and I didn't find anything.Please help me.

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