[cfe-commits] r75168 - in /cfe/trunk: include/clang/Basic/DiagnosticGroups.td include/clang/Basic/DiagnosticSemaKinds.td lib/Sema/SemaDeclCXX.cpp test/SemaCXX/constructor-initializer.cpp test/SemaCXX/warn-reorder-ctor-initialization.cpp

[Fariborz Jahanian]

On Jul 21, 2009, at 1:16 PM, Daniel Dunbar wrote:

> On Tue, Jul 21, 2009 at 10:08 AM, Douglas Gregor<dgregor at apple.com>  
> wrote:
>> On Jul 9, 2009, at 1:00 PM, Fariborz Jahanian wrote:
>>> +    int Last = AllBaseOrMembers.size();
>>> +    int curIndex = 0;
>>> +    CXXBaseOrMemberInitializer *PrevMember = 0;
>>> +    for (unsigned i = 0; i < NumMemInits; i++) {
>>> +      CXXBaseOrMemberInitializer *Member =
>>> +        static_cast<CXXBaseOrMemberInitializer*>(MemInits[i]);
>>> +      void *MemberInCtorList;
>>> +      if (Member->isBaseInitializer())
>>> +        MemberInCtorList = Member->getBaseClass();
>>> +      else
>>> +        MemberInCtorList = Member->getMember();
>>> +
>>> +      int j;
>>> +      for (j = curIndex; j < Last; j++)
>>> +        if (MemberInCtorList == AllBaseOrMembers[j])
>>> +          break;
>>
>> It's too bad that this is O(N^2), but I can't think of a way to make
>> it faster without having the ability to sort the initializer list by
>> its initialization-position. Besides, the initializer list will
>> generally be short.
>
> Am I missing something, why not just create a DenseMap from
> AllBaseOrMembers[j] -> j? (Assuming the contents of that array are
> distinct).
>
> (A SmallDenseMap ideally, if we happened to have that ADT)

I think Doug was making the point that a very small list of  
initializers may not justify
changing the algorithm to make it faster. I don't think setting up a  
DenseMap and populating it
justifies finding a uniqueness of 4 or 5 elements.

- Fariborz

>
>
> - Daniel