[llvm-commits] [llvm] r90512 - /llvm/trunk/lib/VMCore/AsmWriter.cpp

[Devang Patel]

On Dec 4, 2009, at 12:12 AM, Daniel Dunbar wrote:

> Hi Victor,
>
> This is causing a crash in Clang (on its test suite), can you take a
> look? The crash is here:
>            if (isa<Instruction>(N->getElement(n)))
> and N->getElement(n) is null. Perhaps this just needs a null check,
> but I'm not sure if that is supposed to happen.

Yes, Null can happen and it is valid. In fact, most of the MDNodes  
describing location has null as the last element.
-
Devang

>
> - Daniel
>
> On Thu, Dec 3, 2009 at 5:37 PM, Devang Patel <dpatel at apple.com> wrote:
>> Hi Victor,
>> On Dec 3, 2009, at 5:35 PM, Victor Hernandez wrote:
>>
>>> Author: hernande
>>> Date: Thu Dec  3 19:35:02 2009
>>> New Revision: 90512
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=90512&view=rev
>>> Log:
>>> Teach AsmWriter to write inline (not via a global metadata slot)
>>> metadata that contains an instruction
>>>
>>> Modified:
>>>    llvm/trunk/lib/VMCore/AsmWriter.cpp
>>>
>>> Modified: llvm/trunk/lib/VMCore/AsmWriter.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/AsmWriter.cpp?rev=90512&r1=90511&r2=90512&view=diff
>>>
>>> =
>>> =
>>> =
>>> =
>>> =
>>> =
>>> =
>>> =
>>> = 
>>> = 
>>> ====================================================================
>>> --- llvm/trunk/lib/VMCore/AsmWriter.cpp (original)
>>> +++ llvm/trunk/lib/VMCore/AsmWriter.cpp Thu Dec  3 19:35:02 2009
>>> @@ -695,8 +695,13 @@
>>>           !I->hasName())
>>>         CreateFunctionSlot(I);
>>>       for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
>>> -        if (MDNode *N = dyn_cast_or_null<MDNode>(I->getOperand(i)))
>>> +        if (MDNode *N = dyn_cast_or_null<MDNode>(I->getOperand 
>>> (i))) {
>>> +          // Create a metadata slot only if N contains no
>>> instructions.
>>> +          for (unsigned n = 0, e = N->getNumElements(); n != e; + 
>>> +n)
>>> +            if (isa<Instruction>(N->getElement(n)))
>>> +              continue;
>>>           CreateMetadataSlot(N);
>>> +        }
>>>
>>>       // Process metadata attached with this instruction.
>>>       MDs.clear();
>>
>> There are other places where CreateMetadataSlot() is used. Please  
>> move
>> this check in side CreateMetadataSlot().
>> -
>> Devang
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
>>