[LLVMdev] PR5373

[Jakub Staszak]

Hello,

Yeah, sorry, you are right. My new idea is that only one ExitBB is  
found because Header ("for.body") is already marked as visited. I'm  
pretty sure that someone had a good reason to do this that way, but I  
can't find it out :)

Dan, can you look at this patch?

Thanks
-Jakub

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On Nov 30, 2009, at 7:52 PM, Dan Gohman wrote:

> Hello,
>
> Simply removing that "return true" causes the code to search
> blocks outside of loops for side effects. That's not
> what the code is supposed to do.
>
> Dan
>
> On Nov 27, 2009, at 3:01 AM, Jakub Staszak wrote:
>
>> Hi,
>>
>> Because of this "return true" not every block was visited and only  
>> one ExitBB was found (instead of two). Thus, loop was optimized as  
>> a trivial one, which was wrong.
>>
>> -Jakub
>>
>> On Nov 24, 2009, at 2:28 PM, Dan Gohman wrote:
>>
>>> Hello,
>>>
>>> I haven't studied this in detail, but at a first look this makes  
>>> the code inconsistent with the associated comments. Why should the  
>>> code continue recursing past a loop exit?
>>>
>>> Dan
>>>
>>> On Nov 23, 2009, at 4:43 AM, Jakub Staszak <kuba at gcc.gnu.org> wrote:
>>>
>>>> Hello,
>>>>
>>>> This patch fixes pr5373, testcase of course attached.
>>>>
>>>> -Jakub
>>>> <5373.patch>
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>>