similar to: [LLVMdev] Improving GC intrinsics in LLVM

On Oct 6, 2011, at 17:19, Yiannis Tsiouris wrote: > Hello all, > > I set: InitRoots = true; in my gc plugin as i want the roots to be > initialized to the "null" value. > Is there a way to define which value should be the initial one? For > example, i would like to initialize my roots to -5 (tagged, null value > for the GC in my runtime system) instead of 0. >

On Wed, Feb 16, 2011 at 4:51 PM, Talin <viridia at gmail.com> wrote: > I think I'm one of the few people actually using LLVM's support for garbage > collection, and so far I've found it very difficult to generate code that > uses llvm.gcroot() correctly. > > In the current scheme, it is the frontend's responsibility to insure that > any intermediate SSA

On Thu, Feb 17, 2011 at 1:07 PM, Talin <viridia at gmail.com> wrote: > On Wed, Feb 16, 2011 at 4:51 PM, Talin <viridia at gmail.com> wrote: > >> I think I'm one of the few people actually using LLVM's support for >> garbage collection, and so far I've found it very difficult to generate code >> that uses llvm.gcroot() correctly. >> >> In

Hi Chris, Gordon, Here's a patch to allow a GCStrategy to customize the places where it wants to insert safe points. I'm not sure who maintains the GC code today in LLVM (I'd be happy to take ownership, if needed). The patch just adds up a custom safepoints flag, similar to the way the GCStrategy can customize intrinsics lowering, or roots initialization. It works pretty well, as

I'm moving this to a different thread. I think the newly proposed intrinsic definitions and their current implementation are valuable regardless of how it gets tied into GC... On Oct 22, 2013, at 6:24 PM, Philip R <listmail at philipreames.com> wrote: > Adding Gael as someone who has previously discussed vmkit topics on the list. Since I'm assuming this is where the GC support

I'm trying to track down the problem with the assertion failure in SelectionDAGBuilder.cpp. This is the code: *case* *Intrinsic*::gcroot: *if* (GFI) { *const* Value *Alloca = I.getArgOperand(0); *const* Constant *TypeMap = cast<Constant>(I.getArgOperand(1)); * FrameIndexSDNode *FI = cast<FrameIndexSDNode>(getValue(Alloca).getNode());*

*Motivation & Abstract* It has been observed by a number of LLVM users that the current garbage collection framework requires frontends to generate complex and inefficient code. This is primarily due to the fact that only allocas can be stack roots - it is not possible to trace SSA values directly. Because of this limitation, a frontend wanting to support garbage collection has to manually

Hi all, I don't know if I understand everything, but it seems really interesting for a runtime developer, stackmap and patchpoint looks perfect for a lot of optimizations :) I just have few question to verify if I understand what are these stackmaps and patchpoints, and I discuss the GC after. * I have a first very simple scenario (useful in vmkit). Let's imagine that we want to lazily

Hi Talin, I think that the framework for GC assumes llvm.gcroot to be in the first block. If it is not the case in your example, it will break these assumptions. Nicolas On Sun, Sep 26, 2010 at 1:38 AM, Talin <viridia at gmail.com> wrote: > I'm working on the code to handle GC tracing of "intermediate values" (as > described in the GC doc), and I've run into a

I'm working on the code to handle GC tracing of "intermediate values" (as described in the GC doc), and I've run into a weird problem. (Note, this has nothing to do with the patch I have proposed, this error occurs with regular old pointer-allocas.) The exception I am getting occurs in this code here in SelectionDAGBuilder.cpp: *case* *Intrinsic*::gcroot: *if* (GFI) {

On Sat, Dec 29, 2012 at 5:54 PM, Talin <viridia at gmail.com> wrote: > First of all, thanks for looking into this! As you've no doubt discovered, > I'm one of the people who has talked a lot about this issue in the past, and > have been frustrated with the lack of progress in this area. Yeah, I spent some time digging through the archives. Frankly, I'm surprised

I think I'm one of the few people actually using LLVM's support for garbage collection, and so far I've found it very difficult to generate code that uses llvm.gcroot() correctly. In the current scheme, it is the frontend's responsibility to insure that any intermediate SSA values containing references to garbage collectible objects are copied to stack variables so that the GC

> On Oct 26, 2013, at 12:37 AM, Michael Lewis <don.apoch at gmail.com> wrote: > > I'm also highly interested in relocating-GC support from LLVM. Up until now my GC implementation has been non-relocating which is obviously kind of a bummer given that it inhibits certain classes of memory allocation/deallocation tricks. You can implement a copying GC (what the kids these days

Hello all, I set: InitRoots = true; in my gc plugin as i want the roots to be initialized to the "null" value. Is there a way to define which value should be the initial one? For example, i would like to initialize my roots to -5 (tagged, null value for the GC in my runtime system) instead of 0. Ofcourse, i could do it in the frontend (storing -5 to all GC roots), but i was wondering

On Mon, Feb 21, 2011 at 1:50 AM, nicolas geoffray < nicolas.geoffray at gmail.com> wrote: > Hi Talin, > > On Fri, Feb 18, 2011 at 5:50 PM, Talin <viridia at gmail.com> wrote: >> >> >> In the current scheme, the way you tell LLVM that a root is no longer >> needed is by assigning NULL to it. However, that assumes that all roots are >> pointers,

So - here's a really modest proposal: Based on Renato's suggestion, there is a way to associate arbitrary annotation data with any LLVM type. So what I would propose as a first step is to simply replace (or perhaps supplement) the current llvm.gcroot() feature with a type annotation. That is, LLVM would only support roots that are allocas, just it does today. The backend code would not

Now that the statepoint changes have landed, I wanted to start a discussion about what's next for GC support in LLVM. I'm going to sketch out a strawman proposal, but I'm not set on any of this. I mostly just want to draw interested parties out of the woodwork. :) Overall Direction: In the short term, my intent is to preserve the functionality of the existing code, but migrate

On Fri, Oct 25, 2013 at 8:35 PM, Philip Reames <listmail at philipreames.com>wrote: > On 10/25/13 1:10 PM, Ben Karel wrote: > > > > > On Thu, Oct 24, 2013 at 6:42 PM, Sanjoy Das <sanjoy at azulsystems.com>wrote: > >> Hi Rafael, Andrew, >> >> Thank you for the prompt reply. >> >> One approach we've been considering involves

On 02/24/2014 11:27 AM, Andrew Trick wrote: > > On Feb 24, 2014, at 11:17 AM, Philip Reames <listmail at philipreames.com > <mailto:listmail at philipreames.com>> wrote: > >> >> On 02/24/2014 12:45 AM, Andrew Trick wrote: >>> >>> On Feb 21, 2014, at 10:37 AM, Philip Reames >>> <listmail at philipreames.com <mailto:listmail at

On 10/25/13 1:10 PM, Ben Karel wrote: > > > > On Thu, Oct 24, 2013 at 6:42 PM, Sanjoy Das <sanjoy at azulsystems.com > <mailto:sanjoy at azulsystems.com>> wrote: > > Hi Rafael, Andrew, > > Thank you for the prompt reply. > > One approach we've been considering involves representing the > constraint "pointers to heap objects