[llvm-dev] Getting variable names from LLVM Pass

[Dean Michael Berris via llvm-dev]

> On 25 May 2018, at 00:48, Ridwan Shariffdeen <rshariffdeen at gmail.com> wrote:
> 
> Hi Michael,
> 
> Thanks for the help, it seems like you said its not going to be easy. But I will have a try at this, thank you for the link to LibTooling.
> 

It’s not going to be easy if you’re trying to find the name of a variable from the LLVM IR, unless the debugging information is available in the LLVM IR.

If you have access to the original source that Clang knows about (i.e. if it’s C++, C, Objective-C, Objective-C++) then you can use LibTooling. If you have specific questions about using LibTooling, those are better sent to cfe-dev (the mailing list for Clang).

Cheers

> Best
> 
> On Mon, May 21, 2018 at 6:26 PM Dean Michael Berris <dean.berris at gmail.com> wrote:
> 
> 
> > On 21 May 2018, at 18:38, Ridwan Shariffdeen via llvm-dev <llvm-dev at lists.llvm.org> wrote:
> > 
> > Hi,
> > 
> > I want to retrieve the variable names used in a statement, I tried the following snippet, 
> > but it only gives me the variable named in llvm bitcode. I need the variable name in source code. 
> > 
> > for (auto op = I.op_begin(); op != I.op_end(); op++) {
> >                         Value* v = op->get();
> >                         StringRef name = v->getName();
> > }
> > 
> > Is there specific documentation I can refer to implement this?
> > 
> 
> If the source language is something clang knows about, you may have to implement that on top of libTooling, part of clang. Unfortunately it’s not quite straight-forward to get to the source from the LLVM — you’re going to have to rely on a reverse-mapping from the LLVM IR to the higher-level source location, which *might* be doable if there’s debug information associated with the LLVM IR.
> 
> https://clang.llvm.org/docs/LibTooling.html
> 
> Cheers
> 
> -- Dean
> 
> -- 
> Ridwan Shariffdeen
> Graduate Student | National University of Singapore

-- Dean