Bug 113437 – fourthTier: JITCode should abstract exactly how the JIT code is structured and where it was allocated

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Filip Pizlo]

This will make it easier to bring up the LLVM backend.  At first, I'll probably just let LLVM use its own memory allocator.  But even if we do switch to having LLVM use our allocator, we will probably want to give LLVM the ability to allocate the code for a function in multiple chunks, if it wanted to.

But also, making JITCode be more abstract means that in the future we could even have a DFGJITCode, for example, which contains all of the DFGRareData things in CodeBlock.  We could do likewise for the LLInt and Baseline JIT.  This will save memory.

Anyway, I think this is pure goodness.

[Filip Pizlo]

Created attachment 195391 [details]
the patch

[WebKit Review Bot]

Attachment 195391 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/JavaScriptCore/ChangeLog', u'Source/JavaScriptCore/assembler/RepatchBuffer.h', u'Source/JavaScriptCore/bytecode/CodeBlock.cpp', u'Source/JavaScriptCore/bytecode/CodeBlock.h', u'Source/JavaScriptCore/dfg/DFGDriver.cpp', u'Source/JavaScriptCore/dfg/DFGDriver.h', u'Source/JavaScriptCore/dfg/DFGJITCompiler.cpp', u'Source/JavaScriptCore/dfg/DFGJITCompiler.h', u'Source/JavaScriptCore/dfg/DFGOSREntry.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExit.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler32_64.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler64.cpp', u'Source/JavaScriptCore/dfg/DFGOperations.cpp', u'Source/JavaScriptCore/interpreter/Interpreter.cpp', u'Source/JavaScriptCore/jit/JIT.cpp', u'Source/JavaScriptCore/jit/JIT.h', u'Source/JavaScriptCore/jit/JITCode.cpp', u'Source/JavaScriptCore/jit/JITCode.h', u'Source/JavaScriptCore/jit/JITDriver.h', u'Source/JavaScriptCore/jit/JITStubs.cpp', u'Source/JavaScriptCore/jit/ThunkGenerators.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.h', u'Source/JavaScriptCore/llint/LLIntSlowPaths.cpp', u'Source/JavaScriptCore/runtime/Executable.cpp', u'Source/JavaScriptCore/runtime/Executable.h', u'Source/JavaScriptCore/runtime/ExecutionHarness.h']" exit_code: 1
Source/JavaScriptCore/jit/JITCode.h:50:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Source/JavaScriptCore/jit/JITCode.h:79:  The parameter name "jitType" adds no information, so it should be removed.  [readability/parameter_name] [5]
Source/JavaScriptCore/jit/JITCode.h:119:  The parameter name "ref" adds no information, so it should be removed.  [readability/parameter_name] [5]
Source/JavaScriptCore/jit/JITCode.h:119:  The parameter name "jitType" adds no information, so it should be removed.  [readability/parameter_name] [5]
Total errors found: 4 in 27 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Filip Pizlo]

(In reply to comment #2)
> Attachment 195391 [details] did not pass style-queue:
> 
> Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/JavaScriptCore/ChangeLog', u'Source/JavaScriptCore/assembler/RepatchBuffer.h', u'Source/JavaScriptCore/bytecode/CodeBlock.cpp', u'Source/JavaScriptCore/bytecode/CodeBlock.h', u'Source/JavaScriptCore/dfg/DFGDriver.cpp', u'Source/JavaScriptCore/dfg/DFGDriver.h', u'Source/JavaScriptCore/dfg/DFGJITCompiler.cpp', u'Source/JavaScriptCore/dfg/DFGJITCompiler.h', u'Source/JavaScriptCore/dfg/DFGOSREntry.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExit.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler32_64.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler64.cpp', u'Source/JavaScriptCore/dfg/DFGOperations.cpp', u'Source/JavaScriptCore/interpreter/Interpreter.cpp', u'Source/JavaScriptCore/jit/JIT.cpp', u'Source/JavaScriptCore/jit/JIT.h', u'Source/JavaScriptCore/jit/JITCode.cpp', u'Source/JavaScriptCore/jit/JITCode.h', u'Source/JavaScriptCore/jit/JITDriver.h', u'Source/JavaScriptCore/jit/JITStubs.cpp', u'Source/JavaScriptCore/jit/ThunkGenerators.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.h', u'Source/JavaScriptCore/llint/LLIntSlowPaths.cpp', u'Source/JavaScriptCore/runtime/Executable.cpp', u'Source/JavaScriptCore/runtime/Executable.h', u'Source/JavaScriptCore/runtime/ExecutionHarness.h']" exit_code: 1
> Source/JavaScriptCore/jit/JITCode.h:50:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]

Nope.

> Source/JavaScriptCore/jit/JITCode.h:79:  The parameter name "jitType" adds no information, so it should be removed.  [readability/parameter_name] [5]
> Source/JavaScriptCore/jit/JITCode.h:119:  The parameter name "ref" adds no information, so it should be removed.  [readability/parameter_name] [5]
> Source/JavaScriptCore/jit/JITCode.h:119:  The parameter name "jitType" adds no information, so it should be removed.  [readability/parameter_name] [5]

I fixed them.

> Total errors found: 4 in 27 files
> 
> 
> If any of these errors are false positives, please file a bug against check-webkit-style.

[Early Warning System Bot]

Comment on attachment 195391 [details]
the patch

Attachment 195391 [details] did not pass qt-wk2-ews (qt):
Output: http://webkit-commit-queue.appspot.com/results/17304362

[Filip Pizlo]

Created attachment 195393 [details]
the patch

Fixing unresolved symbols.

[WebKit Review Bot]

Attachment 195393 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/JavaScriptCore/ChangeLog', u'Source/JavaScriptCore/assembler/RepatchBuffer.h', u'Source/JavaScriptCore/bytecode/CodeBlock.cpp', u'Source/JavaScriptCore/bytecode/CodeBlock.h', u'Source/JavaScriptCore/dfg/DFGDriver.cpp', u'Source/JavaScriptCore/dfg/DFGDriver.h', u'Source/JavaScriptCore/dfg/DFGJITCompiler.cpp', u'Source/JavaScriptCore/dfg/DFGJITCompiler.h', u'Source/JavaScriptCore/dfg/DFGOSREntry.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExit.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler32_64.cpp', u'Source/JavaScriptCore/dfg/DFGOSRExitCompiler64.cpp', u'Source/JavaScriptCore/dfg/DFGOperations.cpp', u'Source/JavaScriptCore/interpreter/Interpreter.cpp', u'Source/JavaScriptCore/jit/JIT.cpp', u'Source/JavaScriptCore/jit/JIT.h', u'Source/JavaScriptCore/jit/JITCode.cpp', u'Source/JavaScriptCore/jit/JITCode.h', u'Source/JavaScriptCore/jit/JITDriver.h', u'Source/JavaScriptCore/jit/JITStubs.cpp', u'Source/JavaScriptCore/jit/ThunkGenerators.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.cpp', u'Source/JavaScriptCore/llint/LLIntEntrypoints.h', u'Source/JavaScriptCore/llint/LLIntSlowPaths.cpp', u'Source/JavaScriptCore/runtime/Executable.cpp', u'Source/JavaScriptCore/runtime/Executable.h', u'Source/JavaScriptCore/runtime/ExecutionHarness.h']" exit_code: 1
Source/JavaScriptCore/jit/JITCode.h:50:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Total errors found: 1 in 27 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Mark Hahnenberg]

Comment on attachment 195393 [details]
the patch

r=me

[Geoffrey Garen]

> But also, making JITCode be more abstract means that in the future we could even have a DFGJITCode, for example, which contains all of the DFGRareData things in CodeBlock.  We could do likewise for the LLInt and Baseline JIT.  This will save memory.

For a given piece of data, how would you describe the guideline for whether it belongs in JITCode or CodeBlock?

[Filip Pizlo]

(In reply to comment #8)
> > But also, making JITCode be more abstract means that in the future we could even have a DFGJITCode, for example, which contains all of the DFGRareData things in CodeBlock.  We could do likewise for the LLInt and Baseline JIT.  This will save memory.
> 
> For a given piece of data, how would you describe the guideline for whether it belongs in JITCode or CodeBlock?

Specific to a particular execution engine? -> put it in JITCode not CodeBlock.

[Filip Pizlo]

Landed in http://trac.webkit.org/changeset/147014