Bug 156406 – Debug JSC test failure: stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Ryan Haddad]

Debug JSC test failure: stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool

<https://build.webkit.org/builders/Apple%20El%20Capitan%20Debug%20JSC%20%28Tests%29/builds/2401>
<https://build.webkit.org/builders/Apple%20Yosemite%20Debug%20JSC%20%28Tests%29/builds/5530>

stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: ASSERTION FAILED: structureID && structureID < m_capacity
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: /Volumes/Data/slave/elcapitan-debug/build/Source/JavaScriptCore/runtime/StructureIDTable.h(85) : JSC::Structure *JSC::StructureIDTable::get(StructureID)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 1   0x10bf4bcb0 WTFCrash
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 2   0x10bf4bcd9 WTFCrashWithSecurityImplication
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 3   0x10afc087b JSC::StructureIDTable::get(unsigned int)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 4   0x10afc643f JSC::JSCell::structure() const
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 5   0x10b9e3c26 JSC::slowValidateCell(JSC::JSCell*)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 6   0x10afc4835 void JSC::validateCell<JSC::JSCell*>(JSC::JSCell*)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 7   0x10b0b284e JSC::WriteBarrierBase<JSC::PropertyTable>::get() const
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 8   0x10b0b2245 JSC::Structure::checkOffsetConsistency() const
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 9   0x10b0b1dfd JSC::Structure::outOfLineCapacity() const
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 10  0x10b99ab41 bool JSC::JSObject::putDirectInternal<(JSC::JSObject::PutMode)0>(JSC::VM&, JSC::PropertyName, JSC::JSValue, unsigned int, JSC::PutPropertySlot&)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 11  0x10b99a3b9 JSC::JSObject::putInline(JSC::JSCell*, JSC::ExecState*, JSC::PropertyName, JSC::JSValue, JSC::PutPropertySlot&)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 12  0x10b997f94 JSC::JSValue::putInline(JSC::ExecState*, JSC::PropertyName, JSC::JSValue, JSC::PutPropertySlot&)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 13  0x10b98ff7f operationPutByIdNonStrictOptimize
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 14  0x3e9bbd806cc6
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 15  0x10bb76367 llint_entry
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 16  0x10bb6f82e vmEntryToJavaScript
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 17  0x10b98135a JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 18  0x10b91811a JSC::Interpreter::execute(JSC::ProgramExecutable*, JSC::ExecState*, JSC::JSObject*)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 19  0x10b2bd040 JSC::evaluate(JSC::ExecState*, JSC::SourceCode const&, JSC::JSValue, WTF::NakedPtr<JSC::Exception>&)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 20  0x10ae09d83 runWithScripts(GlobalObject*, WTF::Vector<Script, 0ul, WTF::CrashOnOverflow, 16ul> const&, bool, bool)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 21  0x10ae092a4 runJSC(JSC::VM*, CommandLine)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 22  0x10ae086ea jscmain(int, char**)
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 23  0x10ae085ab main
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 24  0x7fff85f995ad start
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: 25  0x8
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: test_script_15896: line 2: 62057 Segmentation fault: 11  ( "$@" ../../.vm/JavaScriptCore.framework/Resources/jsc --useFTLJIT\=false --useFunctionDotArguments\=true --jitMemoryReservationSize\=50000 --useFTLJIT\=true --useConcurrentJIT\=false --thresholdForJITAfterWarmUp\=100 multi-put-by-offset-reallocation-butterfly-cse.js )
stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool: ERROR: Unexpected exit code: 139
FAIL: stress/multi-put-by-offset-reallocation-butterfly-cse.js.ftl-no-cjit-small-pool

[Ryan Haddad]

The JSC change in the failing test run was <https://trac.webkit.org/changeset/199209>

[Filip Pizlo]

I will look.

[Filip Pizlo]

Hey it repros!

[Filip Pizlo]

Heh.  That's awesome.  The bug here is that we are doing a GC from the butterfly allocation call, but we forgot to make the stub be GC-aware.  So, the GC may delete the stub while we're running it.  Here's the stack during the GC moments before we crash:

Requested GC with stack:
1   0x100a339ff JSC::Heap::collectImpl(JSC::HeapOperation, void*, void*, int (&) [37])
2   0x100a3396d JSC::Heap::collect(JSC::HeapOperation)
3   0x1002aa548 JSC::Heap::collectIfNecessaryOrDefer()
4   0x1002aa492 JSC::Heap::decrementDeferralDepthAndGCIfNeeded()
5   0x1002aa468 JSC::DeferGC::~DeferGC()
6   0x1002a8b75 JSC::DeferGC::~DeferGC()
7   0x100b8d55f operationReallocateButterflyToHavePropertyStorageWithInitialCapacity
8   0x22c95a6020c8
9   0x100d6c69d llint_entry
10  0x100d65bde vmEntryToJavaScript
11  0x100b7755a JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*)
12  0x100b0e31a JSC::Interpreter::execute(JSC::ProgramExecutable*, JSC::ExecState*, JSC::JSObject*)
13  0x1004b37a0 JSC::evaluate(JSC::ExecState*, JSC::SourceCode const&, JSC::JSValue, WTF::NakedPtr<JSC::Exception>&)
14  0x100003ed3 runWithScripts(GlobalObject*, WTF::Vector<Script, 0ul, WTF::CrashOnOverflow, 16ul> const&, bool, bool)
15  0x1000033f4 runJSC(JSC::VM*, CommandLine)
16  0x10000283a jscmain(int, char**)
17  0x1000026fb main
18  0x7fff9662b5ad start

Notice operationReallocateButterflyToHavePropertyStorageWithInitialCapacity. My put_by_id transition work added a call to that in the IC.

[Filip Pizlo]

Created attachment 276088 [details]
the patch

[WebKit Commit Bot]

Attachment 276088 [details] did not pass style-queue:


ERROR: Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp:86:  Wrong number of spaces before statement. (expected: 8)  [whitespace/indent] [4]
ERROR: Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp:106:  Wrong number of spaces before statement. (expected: 8)  [whitespace/indent] [4]
Total errors found: 2 in 5 files


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

[Saam Barati]

Comment on attachment 276088 [details]
the patch

r=me

[Filip Pizlo]

Landed in http://trac.webkit.org/changeset/199275