similar to: [LLVMdev] Questions on llvm and jit

Hi Reid. Thanks for your response. We will be running this code in different processes across different nodes. Basically we have thousands of "executor" processes that are solely responsible for executing this code generated at compile-time across partitioned data. Rather than each one of these processes invoking the jit and compiling with full opts and all of that, we believe it may

On Tue, Mar 23, 2010 at 4:44 PM, Shasank Chavan <shanko_chavano at hotmail.com> wrote: > Hi.  I have more questions regarding llvm and using it as a jit for our > purposes.  Also, let me confess that I haven't actually used llvm yet (I'm > still prototyping using gnu's libjit).  Some of the issues that have come up > from that work so far leads to me these questions:

If you really trying to avoid linking everything into a shared library (easiest choice), consider splitting up the compilation into a few more steps: 1) Compile and optimize once as part of your build, target LLVM bitcode instead of machine code 2) Ship .bc files out to each node 3) Fix-up call instructions in a BasicBlockPass, run JIT without any/many additional IR optimizations enabled This

If you distribute the .bc to a new machine and JIT it there, you wouldn't need to apply any relocations to call instructions, since the JIT will get all the offsets right when it does code generation on the node. I would strongly recommend the shared library approach over this one, because JIT compile time is dominated by code generation, not optimization. If you distribute the .bcs, then

Hi. I have a very quick question. Is the instruction cache flushed by the llvm jit before code in memory is written to or executed? I'm assuming so, but I can't find where in the source code this is happening. In particular I searched for clflush, invd, and wbinvd instructions, but couldn't find them. And if it's not necessary to do this, can you please explain why? (I'm

Hi Jim. Thanks for your speedy response. I'm not entirely sure if a JIT is what I'm looking for. I'm basically looking for a dll with an interface that takes a C program as input and compiles and optimizes it to native x86 instructions in an in-memory buffer. I don't want the dll the execute it, and I don't particularly want to translate our expressions into LLVM bitcode

On Sat, Mar 6, 2010 at 10:34 PM, Shasank Chavan <shanko_chavano at hotmail.com> wrote: > Hi.  I have a very quick question.  Is the instruction cache flushed by the > llvm jit before code in memory is written to or executed?  I'm assuming so, > but I can't find where in the source code this is happening.  In particular > I searched for clflush, invd, and wbinvd

This can be done. Last year I took clang (v. 2.5) and hacked the compiler driver into a library which would JIT C source to memory. I then created a Zend extension which utilized the library. No external frameworks were used in these hacks, and were fairly simple to implement once one knew how to use the Clang/LLVM libraries. I cannot speak to your dll requirement, as the work was done for Linux.

On Tue, Feb 2, 2010 at 7:39 PM, Shasank Chavan <shanko_chavano at hotmail.com> wrote: > Hi Jim.  Thanks for your speedy response.  I'm not entirely sure if a JIT is > what I'm looking for.  I'm basically looking for a dll with an interface > that takes a C program as input and compiles and optimizes it to native x86 > instructions in an in-memory buffer.  I don't

Hi. I'm very new to LLVM, and have read some of the documentation online. Before I invest too much time, however, in learning about LLVM, I'd like to know if it can be used for my purpose. We currently have a critical runtime component that evaluates expressions via interpretation. The bytecode that we generate goes through various optimization phases similarly to that of optimizing

On Feb 2, 2010, at 3:05 PM, Shasank Chavan wrote: > Hi. I'm very new to LLVM, and have read some of the documentation online. Before I invest too much time, however, in learning about LLVM, I'd like to know if it can be used for my purpose. We currently have a critical runtime component that evaluates expressions via interpretation. The bytecode that we generate goes through

>>>>> "Jakob" == Jakob Praher <jp at hapra.at> writes: Jakob> I would definitely like to look into it. I'll send it in private email. Jakob> Yes very much! How did you find writing it directly in Jakob> SSA-form. Actually I used what Chris called "the alloca trick"... the JIT doesn't really generate SSA form but instead uses alloca to

>>>>> "Chris" == Chris Lattner <sabre at nondot.org> writes: >> FWIW I actually did this work twice, once for libjit and once for >> LLVM. I'm happy to provide a comparison, from a jit-writing >> perspective, if you're interested. Chris> Given your experience with both, I'd be very interested in any Chris> thoughts you have on

hi Tom, I am really glad that someone has found time to step into that :-). Tom Tromey wrote: > I recently wrote an LLVM-based JIT plugin for libgcj and I thought > it'd be worthwhile to mention it here. > > It is in cvs on sourceforge, but afaics anonymous cvs there is pretty > broken at the moment... so if you want a copy, ask and I will email it > to you. wow. that is

On Tue, 18 Apr 2006, Tom Tromey wrote: > I recently wrote an LLVM-based JIT plugin for libgcj and I thought > it'd be worthwhile to mention it here. Cool! > Exception handling definitely does not work, I didn't even try to > implement it yet. I've been thinking about having some kind of simple > bridge between the LLVM and GCC worlds here -- very inefficient, but >

I recently wrote an LLVM-based JIT plugin for libgcj and I thought it'd be worthwhile to mention it here. It is in cvs on sourceforge, but afaics anonymous cvs there is pretty broken at the moment... so if you want a copy, ask and I will email it to you. Basically I hacked libgcj to (optionally) dynamically load JIT module at startup. If a JIT is loaded then bytecode is passed to it rather

Dear all, First, sorry for all that noise. I know you guys *just don't care*TM, but this requires some clarification. I won't say more than what's in this email. The VMKit paper dates from early 2008. It compares VMKit with pnet 0.7.4 and not the latest release (0.8.0) because we were not able to get any information to build it correctly at the time; the website that hosted

Hi Chris, Just in case that this information does not get corrupted I want to point to the issue: In http://llvm.org/devmtg/2008-08/Geoffray_VMKitProject.pdf it is on page 21: "VMKit, Mono, PNet", Array bounds checks. In http://hal.inria.fr/docs/00/35/45/77/PDF/RR-6799.pdf it is on page 17: "We compare N3 with Mono [9] version 1.2.6, and PNet version 0.7.4 [2], which uses

Dear all, This new version of the paper at: http://hal.archives-ouvertes.fr/docs/00/36/53/37/PDF/RR-6799.pdf got ride of libJIT. Now my question is the how scientific is this research and research paper if instead of using libJIT and Portable.NET JIT: authors of "VMKit: a Substrate for Virtual Machines by Nicolas Geoffray — Gaël Thomas— Charles Clément —Bertil Folliot — Gilles

On Tue, 18 Apr 2006, Tom Tromey wrote: >>>>>> "Chris" == Chris Lattner <sabre at nondot.org> writes: >>> FWIW I actually did this work twice, once for libjit and once for >>> LLVM. I'm happy to provide a comparison, from a jit-writing >>> perspective, if you're interested. > > Chris> Given your experience with both,