Bug 115300

Summary: fourthTier: DFG tries to ref/deref StringImpls in a ton of places
Product: WebKit Reporter: Filip Pizlo <fpizlo>
Component: JavaScriptCoreAssignee: Filip Pizlo <fpizlo>
Status: RESOLVED FIXED    
Severity: Normal CC: barraclough, ggaren, mark.lam, mhahnenberg, msaboff, oliver, sam
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Bug Depends on: 115393, 115468, 115525    
Bug Blocks: 112839    
Attachments:
Description Flags
work in progress
none
starting to run things
none
the patch ggaren: review+

Description Filip Pizlo 2013-04-27 00:00:21 PDT 
I will have to think about this.  I suspect that most uses of StringImpls in the DFG are totally safe.  But the ones that involve debug dumps probably aren't.
Comment 1 Filip Pizlo 2013-04-29 13:24:37 PDT 
Created attachment 200041 [details]
work in progress
Comment 2 Filip Pizlo 2013-04-29 22:16:37 PDT 
Created attachment 200081 [details]
starting to run things

Still more work to do.
Comment 3 Filip Pizlo 2013-04-30 14:52:59 PDT 
Created attachment 200151 [details]
the patch
Comment 4 Geoffrey Garen 2013-04-30 15:03:24 PDT 
Comment on attachment 200151 [details]
the patch

View in context: https://bugs.webkit.org/attachment.cgi?id=200151&action=review

r=me

> Source/JavaScriptCore/runtime/Identifier.h:251
> +    typedef HashMap<StringImpl*, int, IdentifierRepHash, HashTraits<StringImpl*>, IdentifierMapIndexHashTraits> ConcurrentIdentifierMap;

Maybe BorrowedIdentifierMap instead? I don't love "Concurrent" in the name because it might imply safety.
Comment 5 Filip Pizlo 2013-04-30 23:58:59 PDT 
Looks like I need to fix Structure::addPropertyTransitionToExistingStructure().  I'll do that shortly, and commit this after that is fixed.
Comment 6 Filip Pizlo 2013-05-02 19:57:12 PDT 
Landed in http://trac.webkit.org/changeset/149516