[LLVMdev] Question to Chris

Seung Jae Lee lee225 at uiuc.edu
Sat Jan 26 09:48:33 PST 2008

Dear Dr.Lattner 

Hello, Dr.Lattner. 
You may find your reply at http://lists.cs.uiuc.edu/pipermail/llvmdev/2007-August/010479.html and other your replies to me right up and down at the list. 
You had suggested me to read the "structural analysis" section in Muchnick's book. 
Thank you for this. I bought and read it, which was very helpful but... 
I still don't have any idea about how to deal with phi-nodes in LLVM Intermediate Representation systemically to resolve my problem. 
In order to construct high-level 'for' from LLVM IR, it is critical to move Phi-nodes hither and thither or split them but... I can't find any material about this from anywhere. 
So could you reply to me briefly about this if you are fine? 

Thank you very much and have a good day. 
Seung J. Lee 

P.S: In fact, I am thinking about an alternative way for doing this by using reverse engineering. Now that LLVM IR has phi-nodes which is tricky to handle for this issue, I just slightly changed my way to use the machine assembly which does not have phi-nodes. Already someone (like Doug Simon in Sun microsystems) got high-level C code "which is quite same with the original including loops, conditionals and so on" from Sparc assembly by using de-compilation. 
Therefore, if you reply "it is difficult to handle phi-nodes for constructing high-level loops", I am almost ready to go the other way using the machine assembly. 
Anyway, could you shed some lights on me? 
Thank you very much 

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