[LLVMdev] DragonEgg3.3 support for gcc cross compilers
Ajay Panyala
ajay.panyala at gmail.com
Tue Oct 28 11:44:05 PDT 2014
Hi Brian,
Yes, the 64-bit build of the tilera tools should do it (file tile-gcc shows
it to be a 32-bit executable).
I did not setup the tilera toolchain on this machine, but it looks like
tile-gcc was configured as 32-bit by default.
The OS is a 64-bit RHEL 5. I will try the native compiler and target and
also try build the
64-bit tilera gcc and see how it goes. Thanks a lot!
- Ajay
On Tue, Oct 28, 2014 at 11:19 AM, Brian Faull <bfaull at cog-e.com> wrote:
> Hi again Ajay,
>
> I think my knowledge of DragonEgg is now exhausted. :) Still seems like
> this should be possible; here’s a few more questions and suggestions.
>
> Building on Anton says, 32-/64-bit could be the situation:
> * Are you on 32b Linux -- or what architecture are you on (e.g., what does
> `uname -a` give you?
> * Or, how is your tile-gcc configured (e.g., configure --build=? --host=?
> --target=tilera?).
> * If you are on an x86_64 system, you might be using, say, multilib and a
> 32-bit tile-gcc or something. E.g., what does `file tile-gcc` give you?
>
> I still don't think you want to build DragonEgg with tile-gcc. Try
> building dragonegg.so using your system gcc, then using `tile-gcc
> -fplugin=...`
>
> As another hack, it might be possible to put your sources through
> `tile-gcc` just through the preprocessor (e.g., `tile-gcc -E -o ...`) but
> that's a bit of a kludge and depends on what the nature of the
> target-specific items in your sources are.
>
> I think you might want to step back and try to get DragonEgg working on a
> native compiler with native target. Would you try my "first bullet" in my
> original response -- configure native gcc, native llvm, build dragonegg.so,
> then use same to build a helloworld?
>
> Brian
>
>
>
>
> > On Oct 28, 2014, at 2:13 PM, Anton Korobeynikov <anton at korobeynikov.info>
> wrote:
> >
> > What does "file /path/to/tilera-gcc48/bin/tile-gcc" and "file
> > /path/to/dragonegg.so" report?
> >
> > On Tue, Oct 28, 2014 at 9:11 PM, Ajay Panyala <ajay.panyala at gmail.com>
> wrote:
> >> No. The gcc cross compiler being used (tilera-gcc) is indeed 64-bit.
> >>
> >> Thanks
> >>
> >> On Tue, Oct 28, 2014 at 11:01 AM, Anton Korobeynikov
> >> <anton at korobeynikov.info> wrote:
> >>>
> >>> Looks like your gcc is 32-bit and you're trying to load 64-bit plugin.
> >>>
> >>> On Tue, Oct 28, 2014 at 8:27 PM, Ajay Panyala <ajay.panyala at gmail.com>
> >>> wrote:
> >>>> Hi Brian,
> >>>>
> >>>> Thanks for sharing your experience with dragonegg.
> >>>> I would like to use tilera-gcc as the compiler driver. native gcc
> would
> >>>> not
> >>>> be able to
> >>>> handle things like tilera specific intrinsics in the source code.
> >>>>
> >>>> I built dragonegg using
> >>>>
> >>>> GCC=/path/to/tilera-gcc48/bin/tile-gcc
> >>>> LLVM_CONFIG=/path/to/tilera-llvm/bin/tilegx-llvm-config make
> >>>>
> >>>> and also tried only emitting the IR
> >>>>
> >>>> /path/to/tilera-gcc48/bin/tile-gcc -fplugin=/path/to/dragonegg.so
> >>>> -fplugin-arg-dragonegg-emit-ir -S -o hello.ll hello.c
> >>>>
> >>>> (and still get the error: cannot load plugin dragonegg.so: wrong ELF
> >>>> class:
> >>>> ELFCLASS64 )
> >>>>
> >>>> - Ajay
> >>>>
> >>>> On Mon, Oct 27, 2014 at 9:39 PM, Brian Faull <bfaull at cog-e.com>
> wrote:
> >>>>>
> >>>>> Hello,
> >>>>>
> >>>>> There may be plenty more experienced experts on DragonEgg (and
> >>>>> hopefully
> >>>>> they'll correct me if I'm wrong), but I figured I'd chime in with my
> >>>>> brief
> >>>>> experience to start. I have messed with this a bit, and DragonEgg has
> >>>>> worked
> >>>>> for my experiments. Your configuration has many things that are
> >>>>> different
> >>>>> than mine; however, I think you might simply have the cross-compilers
> >>>>> crossed backward; I think you want to use your native gcc as
> >>>>> compiler-driver; pass dragonegg.so to your native-gcc rather than
> >>>>> tilera-gcc. I think you may simply need to do the following:
> >>>>>
> >>>>> 1- Build DragonEgg using your system compiler (or gcc 4.6.4 as
> >>>>> recommended
> >>>>> on dragonegg.llvm.org); when doing `make`, point explicitly at your
> >>>>> *build*
> >>>>> (x86_64) GCC of choice, and against your *target* (tilera)
> >>>>> `llvm-config`.
> >>>>> 2- use your x86_64 compiler-driver as front-end, which due to the
> magic
> >>>>> of
> >>>>> DragonEgg and llvm-config will use your target LLVM backend.
> >>>>>
> >>>>> Or it could be really late and I'm not thinking straight. :)
> >>>>>
> >>>>> More detail:
> >>>>> I had to set a few non-obvious (to me) things in the build and use
> >>>>> process, so I'll reflect them here for you and/or posterity. You
> will
> >>>>> need
> >>>>> all three components though: LLVM backend for your architecture
> >>>>> (tilera)
> >>>>> I'd suggest a few things to try, in order for you to find a
> >>>>> configuration
> >>>>> that works for you:
> >>>>>
> >>>>> * Sounds like you're on x86_64 / AMD64. I'd suggest to start with
> >>>>> building the simplest configuration: using your system compiler to
> >>>>> build
> >>>>> everything for your system native architecture, and this will be the
> >>>>> easiest
> >>>>> configuration to debug.
> >>>>>
> >>>>> * According to the dragonegg.llvm.org web site, DragonEgg works best
> >>>>> with
> >>>>> GCC 4.6. You may wish to try that (I recommend looking at
> >>>>> http://gcc.gnu.org/gcc-4.6/ for GCC 4.6.4, which is the latest
> release
> >>>>> of
> >>>>> that version). I don't know exactly why this version is said to work
> >>>>> best;
> >>>>> perhaps the DragonEgg site is simply stale. I bootstrapped a clean,
> >>>>> native
> >>>>> version of 4.6.4 without much headache.
> >>>>>
> >>>>> * Since I wanted to get DragonEgg built to work with GCC4.6.4, I
> built
> >>>>> DragonEgg with GCC4.6.4. IIRC, the DragonEgg makefile wants you to
> >>>>> specify
> >>>>> the compiler as GCC=... rather than CC=... but it looks like it
> should
> >>>>> eat
> >>>>> both. Also, I read somewhere that LLVM3.3's llvm-config had some
> >>>>> behavior
> >>>>> that argues with DragonEgg. Contrary to best practice "build outside
> >>>>> the
> >>>>> source tree" so as to prevent polluting of the source tree, I saw a
> >>>>> recommendation to build *within* the source tree, so I rolled back
> and
> >>>>> built
> >>>>> LLVM3.3 *in the source tree* (GASP!) for native (x86_64). In sum, to
> >>>>> build
> >>>>> DragonEgg I used something like
> >>>>> GCC=/path/to/gcc464/bin/gcc
> >>>>> LLVM_CONFIG=/path/to/llvm-3.3.src-x86_64/prefix/bin/llvm-config make
> >>>>>
> >>>>> * Then to use this shiny new .so, I started by going only up to the
> >>>>> point
> >>>>> of emitting LLVM IR so as not to confuse the situation with further
> >>>>> architecture-specific compilation/assembly:
> >>>>> /path/to/gcc464/bin/gcc -fplugin=/path/to/dragonegg.so
> >>>>> -fplugin-arg-dragonegg-emit-ir -S -o hello.ll hello.c
> >>>>> I also chose to specify the full path of dragonegg.so, so I didn't
> have
> >>>>> to
> >>>>> be concerned with library paths.
> >>>>>
> >>>>> Then you should be able to manually use your backend (llvm33/bin/llc,
> >>>>> assembler, etc.) to generate an architecture-specific object. Once
> >>>>> you've
> >>>>> got all those components, you should be able to get everything
> >>>>> integrated
> >>>>> with just one gcc compiler-driver invocation.
> >>>>>
> >>>>> HTH,
> >>>>> Brian
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> On Oct 27, 2014, at 11:53 PM, Ajay Panyala <ajay.panyala at gmail.com>
> >>>>> wrote:
> >>>>>
> >>>>> I am using a gcc (v 4.8.2) cross compiler for the tilera
> architecture.
> >>>>> There is an LLVM (v 3.3) cross compiler available for tilera
> >>>>> (http://tilera.github.io/llvm),
> >>>>> but the frontend only has partial support for certain tilera
> intrinsics
> >>>>> and no OpenMP support.
> >>>>>
> >>>>> Hence, I have decided to use DragonEgg (v 3.3) to resolve this. I was
> >>>>> able
> >>>>> to build
> >>>>> DragonEgg, but when I pass the command line argument
> >>>>> -fplugin=dragonegg.so
> >>>>> when compiling with the tilera-gcc I get the error
> >>>>>
> >>>>> cannot load dragonegg.so: wrong ELF class: ELFCLASS64
> >>>>>
> >>>>> i.e. the tilera-gcc does not accept the x86 shared library object
> >>>>> dragonegg.so
> >>>>>
> >>>>> The dragonegg sources were built using the x86 GCC, but the plugin
> >>>>> was built to load into the tilera gcc.
> >>>>>
> >>>>> Could someone please point out what I am missing here.
> >>>>>
> >>>>> Thanks
> >>>>> Ajay
> >>>>> _______________________________________________
> >>>>> LLVM Developers mailing list
> >>>>> LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu
> >>>>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> >>>>>
> >>>>>
> >>>>
> >>>>
> >>>> _______________________________________________
> >>>> LLVM Developers mailing list
> >>>> LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu
> >>>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> >>>>
> >>>
> >>>
> >>>
> >>> --
> >>> With best regards, Anton Korobeynikov
> >>> Faculty of Mathematics and Mechanics, Saint Petersburg State University
> >>
> >>
> >
> >
> >
> > --
> > With best regards, Anton Korobeynikov
> > Faculty of Mathematics and Mechanics, Saint Petersburg State University
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20141028/f1c5a5a0/attachment.html>
More information about the llvm-dev
mailing list