Yes, API wise this seems fine to me as well.
On Tue, Aug 12, 2014 at 2:04 AM, Lang Hames <lha...@gmail.com> wrote: > Hi All, > >> I think this ignores the real problem with the MCJIT debugging interface: >> it doesn't give MCJIT clients any way of directly accessing and parsing the >> debug metadata. > > Sorry - it wasn't clear from my original post, but I'm hoping to improve > debugging APIs in general, not just for the system debugger. > > I think there are two orthogonal concerns here - (1) the debug info format > (and tools for parsing it), and (2) the APIs for getting the debug info to > the people who need it. > > I want to keep these two things separate to allow for clients passing > through debug-info or other annotations that LLVM/LLDB has no idea how to > parse. > > So, here's a sketch of a partial solution for MCJIT clients (we'll leave the > system debugger to a follow-up email): > > On point one, my inclination is that we should use an existing stable debug > info format. Dwarf seems an obvious candidate, given the level of support in > LLVM. As noted, this shouldn't matter to the client - I think there's > general agreement that the debug info parsing support should be available in > LLVM/LLDB. The client shouldn't have to care about debug-info format > specifics unless they want to. (If anybody has a use-case where that > wouldn't work, please speak up). > > Regarding the second point, my current (vague) plan is to introduce a > utility class that, when attached to the execution engine, records the > relocated debug info sections for each JIT'd object. Clients should be able > to query this object to access the debug info sections. We would provide, > either in LLVM or LLDB, debug info parsers that wrap this class to parse the > contained debug info. > > My intent is that use of this API would look something like: > > ExecutionEngine EE = ...; > DebugInfoListener DI = new DebugInfoListener(...); > EE->addEventListener(DI); > EE->addModule(Foo); > EE->addModule(Bar); > > MCJITDebugInfoParser DIP = createMCJITDebugInfoParser(DI); > DIP...; > > Any thoughts/comments on this (admittedly very vague) proposal are very > welcome. Assuming it sounds reasonable so far, I'm going to start hacking up > some patches and basic use cases to serve as a basis for further discussion > (and a tutorial if the eventual proposal is adopted). > > Cheers, > Lang. > > On Mon, Aug 11, 2014 at 2:02 PM, David Chisnall > <david.chisn...@cl.cam.ac.uk> wrote: >> >> On 11 Aug 2014, at 18:06, Eric Christopher <echri...@gmail.com> wrote: >> >> > There's some support (originally forked from lldb) already in llvm to >> > do this. Look at lib/DebugInfo, it's what llvm-dwarfdump, etc are >> > based upon. >> >> Now that lldb is following trunk, it would be really great if some of this >> could be unified. Every time we find a bug, we end up fixing it in both >> places (sometimes we remember, sometimes we find the same bug twice). >> >> David >> >> >> _______________________________________________ >> LLVM Developers mailing list >> llvm...@cs.uiuc.edu http://llvm.cs.uiuc.edu >> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev > > _______________________________________________ lldb-dev mailing list lldb-dev@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev
