[PATCH] D109632: [clang] de-duplicate methods from AST files

[Duncan P. N. Exon Smith via Phabricator via cfe-commits]

dexonsmith added inline comments.


================
Comment at: clang/include/clang/Sema/Sema.h:1434-1436
+    bool addMethod(ObjCMethodDecl *Method) {
+      return AddedMethods.insert(Method).second;
+    }
----------------
rmaz wrote:
> rmaz wrote:
> > dexonsmith wrote:
> > > Hmm, I was imagining that the set would be more encapsulated than this, not just stored in the same place.
> > > 
> > > I'm wondering if the following could be done in a prep commit:
> > > 
> > > - Change Sema::addMethodToGlobalList to a private member function of GlobalMethodPool.
> > > - Make GlobalMethodPool::insert private
> > > - Add `GlobalMethodPool::addMethod(ObjCMethodDecl*,bool,bool)`, which does the second half of Sema::AddMethodToGlobalPool (the parts that don't need Sema's other fields), and change the latter to call the former.
> > > 
> > > WDYT?
> > Definitely neater, will take a look at this later today.
> This might need a slightly different approach, as for the insert use case we have:
> 
> ```lang=cxx
> Sema &S = *getSema();
>   Sema::GlobalMethodPool::iterator Pos =
>       S.MethodPool.insert(std::make_pair(Sel, Sema::GlobalMethodPool::Lists()))
>           .first;
> 
>   Pos->second.first.setBits(Visitor.getInstanceBits());
>   Pos->second.first.setHasMoreThanOneDecl(Visitor.instanceHasMoreThanOneDecl());
>   Pos->second.second.setBits(Visitor.getFactoryBits());
>   Pos->second.second.setHasMoreThanOneDecl(Visitor.factoryHasMoreThanOneDecl());
> 
>   // Add methods to the global pool *after* setting hasMoreThanOneDecl, since
>   // when building a module we keep every method individually and may need to
>   // update hasMoreThanOneDecl as we add the methods.
>   addMethodsToPool(S, Visitor.getInstanceMethods(), Pos->second.first);
>   addMethodsToPool(S, Visitor.getFactoryMethods(), Pos->second.second);
> ```
> 
> At the moment we fetch a method list, modify its state and then start inserting the methods. If we move to something like `MethodPool.addMethod(ObjCMethodDecl *)` we will have to look up the method list for each insert, and we would need extra methods to set the state first on the method list. How about something like `MethodPool.addMethods(ArrayRef<ObjCMethodDecl*> methods, unsigned instanceBits, bool hasMoreThanOneDecl)`? Then we only need two list lookups per selector as before and we can handle the list state update before insert.
>  
That seems reasonable to me.


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  https://reviews.llvm.org/D109632/new/

https://reviews.llvm.org/D109632