similar to: [LLVMdev] Garbage collection implementation

On Thursday 18 June 2009 12:28:57 Cory Nelson wrote: > I'm also curious what language uses this and why it is useful :) HLVM is intended to be a general-purpose VM rather than a particular language. > Also, things like this would make lock-free algorithms difficult or > impossible. True. Perhaps that is a good argument for providing both kinds. However, nulls are certainly more

> > That is similar to the approach I used, although HLVM provides a pointer directly to the type, saving you a single hop. I'm not so sure that is a very good reason, depending on your implementation data structures that are fundamental to the type system of the virtual machine use custom allocators so the extra hop carries little to no expense. I would not have considered it had I

On Thu, Jun 18, 2009 at 3:14 AM, Granville Barnett<granvillebarnett at googlemail.com> wrote: > >> Firstly, rather than using a single 1 word pointer to represent a >> reference I >> chose to use 3 words including a pointer to the type and a pointer to the >> value (as well as metadata). This allows typed nulls and that addresses an >> important deficiency

> Firstly, rather than using a single 1 word pointer to represent a reference > I > chose to use 3 words including a pointer to the type and a pointer to the > value (as well as metadata). This allows typed nulls and that addresses an > important deficiency found in most other VMs including the CLR. Is Scarcity > able to handle such references or does its implementation of stack

What happened to the HLVM project? I understand it was intended to be a high-level VM specifically for dynamic languages and this post indicates that it was integrated into the LLVM project last year: http://www.nabble.com/NEWS:-HLVM-merges-with-LLVM-td9627113.html But I cannot find any code in LLVM that looks like it would have come from HLVM. -- Dr Jon Harrop, Flying Frog Consultancy

On Tuesday 16 June 2009 15:44:04 Aaron Gray wrote: > Jon Harrop wrote: > >Even if this puts LLVM at an unfair disadvantage, I think you will find > >that > >LLVM will thrash MLton's current x86 backend anyway. > > > >I did some benchmarking on HLVM and found that it was often several times > >faster than OCaml when the GC is not the bottleneck: > >

Am 16.12.2011 21:06, schrieb Jon Harrop: > At regular intervals, check if the heap size has exceeded its quota > and, if so, run a GC cycle. I have seen people recommend doing this kind of check whenever hitting a malloc call. I think it nicely scales with the level of heap activity for most programs.

David Given wrote: > Are there any standalone accurate garbage collectors that I could use in my > project, rather than having to write me own (or use libgc, which is what I'm > doing now)? Garbage collectors are subtle and very tricky and I really don't want > to have to do one myself, as I know I'll just get it wrong. On the contrary, writing your own GC is both easy and

Someone is trying to work on HLVM with me but they're hitting a problem that we have not been able to resolve. Specifically, GCC seems to be performing some kind of sanity check for "stack smashing" and is calling abort because it is unhappy with something that the code is doing. However, I am not sure what and cannot reproduce the problem. The stack trace they have given me is:

>On Sunday 14 June 2009 14:09:33 Wesley W. Terpstra wrote: >> On Sun, Jun 14, 2009 at 10:50 AM, Florian Weimer<fw at deneb.enyo.de> wrote: >> > Is this really a problem for MLton? I think you only get less precise >> > alias analysis, and that's it. >> >> Correct. However, I want a fair comparison between LLVM performance >> and the native x86

tail calls are only implemented for fastcall calling convention if i remeber right from my inquiries. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20091112/e8f1dd2a/attachment.html>

Resent, to the list this time instead of David (sorry for the duplicate)... On Thu, Nov 12, 2009 at 9:57 PM, David Terei <davidterei at gmail.com> wrote: > I've run into some issues with tail calls in the past, make sure you > are doing the following: > > 1. Call should be marked with tail (obviously) > 2. Next statement after tail call should be 'return void'

Talin wrote: > Jon wrote: > > Talin wrote: > > > Garbage collection is still way too difficult. > > > > This is completely untrue. > > I'm afraid I'm going to have to disagree... I failed to get my point across. You're still talking about the difficulty of using LLVM's GC support. I was talking about circumventing it. The shadow stack HLVM uses

On Tue, Feb 16, 2010 at 2:47 AM, Jon Harrop <jon at ffconsultancy.com> wrote: > On Tuesday 16 February 2010 03:51:00 Jianzhou Zhao wrote: >> Does anyone know if there is any realistic project using LLVM-OCaml >> Bindings? > > I've written a VM in OCaml built upon LLVM using LLVM's OCaml bindings: > >  http://www.ffconsultancy.com/ocaml/hlvm/ > > There

On Sun, Jan 4, 2009 at 2:36 PM, Jon Harrop <jon at ffconsultancy.com> wrote: (...) > But I cannot find any code in LLVM that looks like it would have come from > HLVM. Don't know about the status of the project, but the code seems to be here: http://llvm.org/viewvc/llvm-project/ (in directory "hlvm") Regards, Kevin André

Would you then agree with me that "LLVM's garbage collection facilities, _as described in the LLVM documentation_, are too difficult to use"? On Tue, Dec 6, 2011 at 3:40 AM, Jon Harrop < jonathandeanharrop at googlemail.com> wrote: > Talin wrote: > > Jon wrote: > > > Talin wrote: > > > > Garbage collection is still way too difficult. > >

On 04/01/2010, at 3:01 PM, Jon Harrop wrote: > On Monday 04 January 2010 01:12:55 Simon Harris wrote: >> I'm investigating "improving" the TCO facilities in LLVM to provide for >> "hard" tail calls. Specifically, this would involve extending the existing >> implementation to discard the stack frame for the caller before executing >> the callee. I

I am using LLVM as the last stage of a compiler in order to easily produce a binary in native code. My compiler is implemented in Ocaml and has various layers of languages. In the last layer prior to LLVM, I have a value which has been converted to CPS, closure and hoisting (of functions). I am now trying to write a garbage collector for this language. The shadow stack is not suitable for me,

I just upgraded HLVM from LLVM 2.7 to 2.8 and started seeing stack overflows so I think TCO isn't working. Have there been any obvious changes that would cause this? -- Dr Jon Harrop, Flying Frog Consultancy Ltd. http://www.ffconsultancy.com

Following on from the success of our previous OCaml Journal articles covering LLVM, we have begun a series dedicated to the design and implementation of high-level languages using LLVM. In particular, these new articles are more pragmatic in nature and go beyond describing working compilers to also discuss testing, debugging and the performance of LLVM-based compilers. The first article in