[LLVMdev] Fix crash in llvm_gcda_emit_arcs()

[Joseph Kain]

Hi Nick and Bill,

Attached is a new version of the patch that checks against cur_buffer_size.
This works with the cases I've been using but again I haven't run the
official tests on this change.

Thanks,
Joseph Kain



On Thu, Sep 5, 2013 at 9:46 AM, Joseph Kain <joekain at gmail.com> wrote:

> Hi Nick,
>
> Thanks for looking over my patch.  I'd be happy to add the compare against
> cur_buffer_size.  I'll try to write up such a change today and then send a
> new patch to the list.
>
> Joseph Kain
>
>
> On Thu, Sep 5, 2013 at 1:37 AM, Nick Lewycky <nicholas at mxc.ca> wrote:
>
>> Bill, could you take a look at this? I don't have a checkout of
>> compiler-rt that builds.
>>
>> It seems obviously-correct to me, but I wish it did a compare against
>> cur_buffer_size to make sure it's in range.
>>
>> Nick
>>
>> Joseph Kain wrote:
>>
>>> Hi,
>>>
>>> I've been seeing a crash in llvm_gcda_emit_arcs() on x86_64.  The crash
>>> occurs executing a movdqa instruction with an unaligned src address.
>>>   The attached patch to the compiler-rt project fixes the problem by
>>> using memcpy() to read data from the write_buffer[] in GCDAProfiling.c.
>>>
>>> This is my first patch submission to llvm so please let me know if I've
>>> missed any steps.  I'm not on the mailing list so please include me on
>>> any replies.
>>>
>>> I haven't run the tests on this change but would be happy to do so if
>>> someone could point me to documentation on how to do so.  I couldn't
>>> find testing instructions linked from
>>> http://llvm.org/docs/**DeveloperPolicy.html<http://llvm.org/docs/DeveloperPolicy.html>.
>>>  I have built the change and
>>> run it with the programs I was testing originally.  With this change the
>>> crash no longer occurs.
>>>
>>> Thanks,
>>> Joseph Kain
>>>
>>>
>>> ______________________________**_________________
>>> LLVM Developers mailing list
>>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
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>>>
>>
>>
>
>
> --
> Joseph Kain
>



-- 
Joseph Kain
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