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Viewing profile — jdoerfert

jdoerfert

HN member
Joined
Mon, Dec 02, 2019, 4:25 AM UTC
HN karma
34
Public activity
10 items

About jdoerfert

I'm Johannes, a compiler (LLVM) guy working on various things including: parallelism (the OpenMP language and OpenMP optimization), interprocedural optimization (LLVM Attributor), polyhedral optimization (PolyhedralValueAnalysis, before Polly).

Recent public activity

  1. comment
    Comment #37312165

    This is not true. 3. is supported by AMD on new hardware, e.g., Frontier. See https://docs.olcf.ornl.gov/systems/frontier_user_guide.html#...

  2. comment
    Comment #36565251

    Yes, though with caveats. The driver and parts of the extended API we used to lower CUDA calls are in upstream LLVM. The wrapper headers are not. We will continue the process of ge…

  3. comment
    Comment #36553375

    Shameless plug: https://www.osti.gov/servlets/purl/1892137 TLDR; If you provide even more functions through the overloaded headers, incl. "hidden ones", e.g., `__cudaPushCallConfig…

  4. comment
    Comment #25721292

    Generally, yes. Though, as always, these things are hard to summarize in one sentence and depend on the standard version (pre/post C++11). This post might shed some light on the op…

  5. comment
    Comment #25721229

    Since https://reviews.llvm.org/D86841 , ~ Aug 2020, Clang is able to reason about the forward progress guarantees of the input. For the LLVM-IR handling see https://reviews.llvm.or…

  6. comment
    Comment #25721175

    FWIW, `noalias`, aka. `__restrict__`, generally works fine but the inliner translates it into `noalias` metadata which is, still, ambiguous and also not handled properly in some ca…

  7. comment
    Comment #22334196

    Does this sound interesting: http://llvm.org/docs/ProgrammersManual.html#llvm-adt-indexed... http://llvm.org/doxygen/IndexedMap_8h_source.html

  8. comment
    Comment #22324729

    Clang will not "reduce compilation effort" and I do not believe GCC does that. There are heuristics that look at things like function size but I don't think that is what they mean.…

  9. comment
    Comment #21811557

    The godbolt compiler explorer, which is awesome btw, had to tackle all sorts of problems like this. I think there is a talk on YouTube that goes into some detail.

  10. comment
    Comment #21679819

    It would be news to me that the PolyhedralInfo interface is actually used anywhere. As the file comment says, this was "work in progress" a few years ago and it shares the same dra…