llvm dev - Nov 2019 - SelectionDAGBuilder-may by a bug

hello all
  
  when i use ollvm from github.com
<http://github.com/>:heroims/obfuscator.git [version 5.0.0] to obtuscate
my c++ code.

  I got a endless loop in llvm SelectionDAGBuilder.cpp:findUnwindDestinations
function.

    
 the 1349 - 1351 line is my debug code.  
 the code run in 1353 line branch. and return to 1327 line.  
   
 I don’t known in this function how to handle LoadInst?  help!! 

 
thanks.


魏平顺  |  高级工程师
北京数美时代科技有限公司
手机/微信: 18510971882/313275773
邮箱: weipingshun at ishumei.com
网址: www.ishumei.com
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Hello

Well, in general – you cannot. Landing pad destination blocks are very
precious and should not have anything extra. It's likely that ollvm
simply does not handle them properly and needs to be fixed.

On Thu, Nov 28, 2019 at 6:32 AM weipingshun via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>
>
> hello all
>
>   when i use ollvm from github.com:heroims/obfuscator.git [version 5.0.0]
to obtuscate my c++ code.
>
>   I got a endless loop in llvm
SelectionDAGBuilder.cpp:findUnwindDestinations function.
>
>
>  the 1349 - 1351 line is my debug code.
>  the code run in 1353 line branch. and return to 1327 line.
>
>  I don’t known in this function how to handle LoadInst?  help!!
>
>
> thanks.
>
>
> 魏平顺  |  高级工程师
> 北京数美时代科技有限公司
> 手机/微信: 18510971882/313275773
> 邮箱: weipingshun at ishumei.com
> 网址: www.ishumei.com
> 地址: 北京市朝阳区来广营西街诚盈中心1号楼3A室
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev


-- 
With best regards, Anton Korobeynikov
Department of Statistical Modelling, Saint Petersburg State University
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Hi,

On Thu, 28 Nov 2019 at 03:32, weipingshun via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>  I don’t known in this function how to handle LoadInst?  help!!
That code looks dodgy, but it should only cause a problem if the input
IR is malformed. findUnwindDestinations is only called on unwind
destination blocks (successors of invoke or cleanupret), and they must
start with one of those kinds of instructions.

Cheers.

Tim.

hello all

I found ollvm  use -bcf may change any block (include Landing pad block).  I
fixed the ollvm code not change landing pad block. now it’s work fine.


 thanks very much! 

Cheers.

魏平顺  |  高级工程师
北京数美时代科技有限公司
手机/微信: 18510971882/313275773
邮箱: weipingshun at ishumei.com
网址: www.ishumei.com
地址: 北京市朝阳区来广营西街诚盈中心1号楼3A室


> 在 2019年11月27日，下午9:02，weipingshun <weipingshun at ishumei.com> 写道：
> 
> findUnwindDestinations
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