[LLVMdev] Is it possible to use EE within optimization pass?

[bhavani krishnan]

I realize my questions may not have been so clear. To give more details. I am writing a fuction pass. I want to interpret some of the instructions within the function pass. In order to do so, I need to create an EE object within the function pass. Now, If I compile and execute using opt. I get an error(Error loading symbol) at the line where I am creating EE. 
opt: symbol lookup error: ../../../build/Release/lib/Try.so: undefined symbol: _ZN4llvm15ExecutionEngine6createEPNS_14ModuleProviderEbPSs

So, I thought I need to link the EE library files as it is not able to load EE. In order to do so, I added the line LINK_COMPONENTS=engine to the Makefile. Now, when I execute using opt, I get the error that the pass is registered multiple times. I know that there has to be a way out of this. Please let me know how I should link/load the EE library files with my optimization pass.

I hope the question is clear now. Sorry for repeating so many times.
thanks,
Bhavani


--- On Mon, 10/27/08, John Criswell <criswell at cs.uiuc.edu> wrote:

> From: John Criswell <criswell at cs.uiuc.edu>
> Subject: Re: [LLVMdev] Is it possible to use EE within optimization pass?
> To: "bhavi63 at yahoo.com" <bhavi63 at yahoo.com>
> Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu>
> Date: Monday, October 27, 2008, 3:22 PM
> bhavani krishnan wrote:
> > Thanks John! My pass is registered only in 1 cpp file.
> It registers and executes fine without the EE.
> >
> > I only get the Pass registered multiple times error
> when I try to link to the EE by using LINK_COMPONENTS=engine
> in the Makefile. Without that line in the Makefile, my pass
> gets registered fine but it is not able to create EE(Error
> reading Symbol). So, how do I link LLVMExecutionEngine.o
> without causing the multiple registration error.
> >   
> Just to make sure we've covered all the obvious stuff,
> are you sure that 
> the name of your pass (the name you use when you execute it
> with the opt 
> command) is unique?  Is the class name of your pass unique?
> 
> -- John T.
> 
> > thanks,
> > Bhavani
> >
> > --- On Mon, 10/27/08, John Criswell
> <criswell at cs.uiuc.edu> wrote:
> >
> >   
> >> From: John Criswell <criswell at cs.uiuc.edu>
> >> Subject: Re: [LLVMdev] Is it possible to use EE
> within optimization pass?
> >> To: "bhavi63 at yahoo.com"
> <bhavi63 at yahoo.com>, "LLVM Developers Mailing
> List" <llvmdev at cs.uiuc.edu>
> >> Date: Monday, October 27, 2008, 3:01 PM
> >> bhavani krishnan wrote:
> >>     
> >>> Hi all,
> >>>
> >>> I am repeating my question from yesterday coz
> I need
> >>>       
> >> to find a solution to this ASAP. 
> >>     
> >>> How do I link the executionengine to an
> optimization
> >>>       
> >> pass. If I use LINK_COMPONENTS=engine in the
> Makefile, I get
> >> the Pass registered multiple times error. And if i
> dont use
> >> anything, it is not able to load the EE. It gives
> error
> >> loading symbol error. So,
> >>     
> >>> 1. Is it possible to use the EE within an
> optimization
> >>>       
> >> pass?
> >>     
> >>> 2. If it is possible, how do I do it?
> >>>   
> >>>       
> >> I have a hunch that I know what your problem is.
> >>
> >> You said that your pass is getting registered
> twice.  Are
> >> you sure that 
> >> your RegisterPass declaration is only being called
> once?  A
> >> common error 
> >> is to put the RegisterPass<MyPass> Foo
> variable
> >> inside a header file 
> >> that gets included by multiple .cpp files
> implementing your
> >> pass (I'm 
> >> assuming you've written a custom pass here). 
> This will
> >> cause your pass 
> >> to get registered multiple times, which will make
> the LLVM
> >> pass manager 
> >> unhappy.
> >>
> >> I believe this is because the RegisterPass<>
> >> constructor does pass 
> >> registration, so if it's declared multiple
> times, it
> >> registers the pass 
> >> multiple times.
> >>
> >> To fix it, put RegisterPass<YourPassName>
> inside one
> >> of the .cpp files 
> >> implementing your pass.
> >>
> >> Regarding your more specific questions, I suspect
> that EE
> >> can be used 
> >> with the Pass Manager to run optimization passes,
> but
> >> that's just a 
> >> guess on my part; I have never done it myself.  I
> suspect
> >> the issue is 
> >> just getting the right libraries listed in
> LINK_COMPONENTS
> >> and making 
> >> sure your pass isn't registered twice.
> >>
> >> Please let us know if the RegisterPass thing is
> the problem
> >> and whether 
> >> the solution above fixes it.
> >>
> >> Regards,
> >>
> >> -- John T.
> >>
> >>
> >>     
> >>> Please help me out here!
> >>> Thanks,
> >>> Bhavani
> >>>
> >>>
> >>>
> >>>       
> >>>
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> >>>
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> >>>
> >>>       
> >
> >
> >       
> >