similar to: ORC JIT Weekly #6 -- General initializer support and JITLink optimizations

Hi All, The initializer patch review at https://reviews.llvm.org/D74300 has been updated. The new version contains a MachOPlatform implementation that demonstrates how Platforms and ObjectLinkingLayer::Plugins can work together to implement platform specific initialization. In this case, the MachOPlatform installs a plugin that scans objects for __objc_classlist and __objc_selref sections and

Hi All, In the interests of improving visibility into ORC JIT development I'm going to try writing weekly status updates for the community. I hope they will provide insight into the design and state of development of LLVM's JIT APIs, as well as serving as a convenient space for discussions among LLVM's large and growing community of JIT API users. The length and detail will vary

Hello, I recently hit an issue when JIT'ing my generated IR using llvm::orc::LLJIT. My IR contains the following definition of a global variable: > $_ZZ23TestStaticVarInFunctionbE1x = comdat any > @_ZZ23TestStaticVarInFunctionbE1x = linkonce_odr dso_local global i32 123, > comdat, align 4 > And in my host process, there exists the same symbol. I would expect LLJIT to resolve the

Hi All, I've listed the current topics of interest below, along with some notes on each. We only have 30 minutes so we'll barely scratch the surface of these during the BoF itself. My main aims are for you to meet each other, identify potential areas of collaboration, identify things that I can do to unblock you, and get the ball rolling on some conversations that we can continue on the

Hi All, There was only one interesting ORC-specific commit this week: A new example showing how to initialize and de-initialize JITDylibs has been added in llvm/examples/OrcV2Examples/LLJITWithInitializers. The Extensible RTTI system (https://reviews.llvm.org/D39111) that I posted a while back has landed. While this is not ORC specific, I expect it to be used in upcoming patches to allow ORC

Hello, I am trying to run this basic C++ hello-world code in my iOS app that has LLVM libraries linked in (the app runs on the actual device - iPad Pro, iOS 13.4.1). #include <iostream> int main (int argh, char *argv[]) { std::cout << "Hello World!" << std::endl; return 0; } So below is the break down of the steps that I do: First I compile this code to an

Hi Lang, Please see below is the trace. -- Thanks, Igor *2020-06-06 12:05:21.016705-0400 CppDevProCompiler[6613:3000073] Running...* *jitLink_MachO: magic = 0xfeedfacf, identifier = "llvm-link.submodule-jitted-objectbuffer"* *jitLink_MachO: cputype = 0x0100000c, cpusubtype = 0x00000000* *Creating normalized sections...* * __text: 0x0000000000000000 -- 0x0000000000000064, align:

Hi Dave, Yep. This is JITLink specific, so we could only have observed it on MachO x86-64 or arm64 until recently. It takes a little bit of poking to get IR to produce a zero-lengh section on MachO, but not much. Jared Wyles recently contributed an initial JITLink ELF implementation, so the fix seems timely -- we might have been about to see more of it. -- Lang. On Fri, Jun 19, 2020 at 4:02 PM

Hey Lang, I would be really happy to only have one LLJIT instance and using multiple JITDylibs. However… it seems like that I don’t know enough to use them. So I wonder… 1. When I add Module A to JITDylib A and Module B to JITDylib B – where will those look for undefined symbols? Will Module A for example: will it only search itself and the MainDylib? Or would it also search in JITDylib B?

Hi All, I've updated the orcv1 removal branch ( https://github.com/lhames/llvm-project/tree/orcv1-removal) with an initial patch for removable code. If anyone wants to follow along with the development or share thoughts on the design you're very welcome to. I'll be adding tests and comments this week, but for anyone who wants to take an early look the main elements are defined in

Hey Lang, Woah! That mail contains a lot of information and things I never tried yet… Actually… the entire MaterializationUnit and MaterializationResponsibility part is… quite… overwhelming >O< With “pop up” I mean… the process which is waiting for Module “Planschi” to “pop up” can not do a thing about it. It just waits until there is an table entry for it, indicating that the object file

Hi Andres, That would be of interest to me too. One thing around this I have been > wondering about is whether it's realistic to merge the optimization and > code generation phases - right now we spend a lot of time re-doing > analyses during codegen that we already had done during optimization. Sounds good to me. I think there are two sub-topics here: (1) JIT specifics. E.g. What

Hi Geoff, We use LLJIT. Do addObjectFile() and StaticLibraryDefinitionGenerator work > for ELF objects? They do. :) I've not tested StaticLibraryDefinitionGenerator extensively on Linux. but we have a regression test checking basic usage. If you run into any trouble at all please file a bug and assign it to me. -- Lang. On Mon, Sep 28, 2020 at 2:05 PM Geoff Levner <glevner at

Hi Geoff, Importing symbols into the JIT from an object file or static library...? Sure! Are you interested in doing this with the C API, LLJIT, or raw OrcV2 components? The high-level answer here (which we can dig into further in the BoF) is: For object files: - For raw OrcV2 components you'll want to create an RTDyldObjectLinkingLayer or ObjectLinkingLayer and use the 'add'

Hi Andres, I also want to highlight the necessity of some form of C API, that others > already have. > <snip> > It's fine if the set of "somewhat stable" C APIs doesn't provide all the > possible features, though. Ok. This got me thinking about what a simple LLJIT API should look like. I have posted a sketch of a possible API on http://llvm.org/PR31103 . I

We are trying to switch to the new orc v2 lljit engine at my work with hopes of parallel jitting. We are switching from the ExecutionEngine w/ OrcMCJitReplacement. We are having a hard time with global variables. We have found a way to create/emit new globals during jitting by using the old ExecutionEngine::getOrEmitGlobalVariable. Is there an easier way to do this with the new jit engine? We were

Hmm, I'm confused. The DSO is compiled with gcc. Do I need to compile it with clang instead? I don't believe the JITted code uses the thread support library directly, although I suppose it may be hidden with templates and/or inline functions... On Mon, Sep 28, 2020 at 10:43 PM Lang Hames <lhames at gmail.com> wrote: > > Hi Geoff, > > If you want to access the variable

Hey Lang, > Do you mean that the object file is produced by another process and is being loaded into your JIT process for execution, or that you want your JIT to produce code for several different processes? These are different problems with different solutions. I'll wait until I understand your use case to answer further. In the current state we don’t have a JIT only an handcrafted object

Hi, Lang As a starter using LLVM JIT to improve OLAP execution engine performance, I'm very glad to hear that. I can't find some useful document help me get start to use the new ORC JIT API quickly. Only can find some examples how to use it, but don't know the internal from low level, and very blurred to design a clearly JIT toolset. Hope more tutorials add in and help ORC JIT more

Hi JITters, I have some JIT-compiled C++ code that uses symbols from a DSO which uses C++14's thread support library. When I compile it I get the following error message: Symbols not found: [ __emutls_v._ZSt15__once_callable, __emutls_v._ZSt11__once_call ] Those seem to correspond to std::__once_callable and std::__once_call, which are indeed present in the C++ standard library. And I