similar to: Passing stack pointer to statepoint-gc

Sorry, what does "PC" mean here? ________________________________ From: Philip Reames <listmail at philipreames.com> Sent: Thursday, November 8, 2018 7:27 AM To: Jordan Rudd; llvm-dev at lists.llvm.org Subject: Re: [llvm-dev] Passing stack pointer to statepoint-gc Jordon, First of all, StackMaps are keyed by PC, not by SP. Each entry corresponds to given location within the

Jordon, I just submitted a change to the docs to hopefully address your confusion.  Can you take a look and let me know if you have further questions?  Start with the revised Stack Map Format section. Philip p.s. I just submitted this and it'll take a few minutes to refresh.  In the meantime, you could look at the diff for 346405. On 11/2/18 2:52 PM, Jordan Rudd via llvm-dev wrote:

[+CC llvm-dev this time] Hi, As discussed in the review thread in http://reviews.llvm.org/D16439, the future plan around statepoints, deopt bundles, PlaceSafepoints etc. is to "constant fold" -spp-no-statepoints and -rs4gc-use-deopt-bundles to true. We (Azul) have moved to a representation of safepoint polls, deopt state etc. that enables us to do the above; and at this point I'm

Hello LLVM community, We have been experimenting with using LLVM IR as a target for a managed (dynamically typed) language via an AOT compiler (including a backend for ARM). One main challenge is getting the garbage collection right: We would like to be able to implement a moving collector. This requires us to a) find a precise set of root pointers and b) be able to rewrite those pointers after

Hi, I'm trying to build a gc using the statepoint-example strategy. However, after hours of searching, reading documentation and trying to find code examples online, I cannot figure out how to access the Stack Map. The documentation for statepoint-example says: The stack map format generated by this GC strategy can be found in the Stack Map

Hi, I am looking to utilize LLVM as the backend in an existing compiler for a garbage collected language, and have a question regarding the current and future support for precise GC in LLVM. It appears that gc.root is being phased out, with with breaking changes such as this: http://reviews.llvm.org/D7004 <http://reviews.llvm.org/D7004> Does this mean that gc.statepoint is ready for

Hi Martin, Philip covered all of it very well, I'll just add one minor comment: > More generally, can I back up and ask an important question? Do you have to > support deoptimization (i.e. osr side exits) in any form? If you do, you'll > probably want to avoid the PlaceSafepoints utility pass. If you need to PlaceSafepoints is inadequate only if you have asynchronous

The long term plan is a) evolving, and b) dependent on the specific use case. :) It would definitely be nice if we could support both early and late safepoint insertion. I see no reason that LLVM as a project should pick one or the other since the infrastructure required is largely overlapping. (Obviously, I'm going to be mostly working on the parts that I need, but others are always

As part of adding `"deopt"` operand bundles, we're aiming to change RewriteStatepointsForGC (called RS4GC henceforth) from rewriting existing `gc.statepoint` calls to transforming normal LLVM calls and invokes into `gc.statepoint` calls and invokes (i.e. to do PlaceSafepoints + RS4GC in one step). This will make `gc.statepoint` an artifact of the gc lowering strategy that only

I've been looking at inlining invokes / calls done through statepoints and I want to have a design discussion before I sink too much time into something I'll have to throw away. I'm not actively working on adding inlining support to patchpoints, but I suspect these issues are applicable towards teaching LLVM to inline through patchpoints as well. There are two distinct problems to

Hi everyone, We seem to have allowed our documented target-independent intrinsics to acquire a somewhat-haphazard naming system, and I think we should standardize on one convention. All of the intrinsics have 'llvm.' as a prefix, and some also have some additional prefix 'llvm.dbg.', 'llvm.eh.', 'llvm.experimental.', etc., but after that we lose consistency. When

Hi, Sanjoy, On 2015-11-16 23:27, Sanjoy Das wrote: > Hi Vlad, > > vlad via llvm-dev wrote: >>> Vlad, >>> >>> My initial impression is that you've stumbled across a bug. I suspect >>> that we - the only active users of the deopt info in the statepoint I >>> know of - have been inverting the meaning of Direct and Indirect >>>

> Vlad, > > My initial impression is that you've stumbled across a bug. I suspect > that we - the only active users of the deopt info in the statepoint I > know of - have been inverting the meaning of Direct and Indirect > throughout our code. (i.e. we're consistent, but swapped on the > documented meaning) I've asked Sanjoy to confirm that, and if he >

Hello, I've spent some time with the LLVM documentation and am beginning to grasp a few things, but I sometimes need very literal statements to actually understand things. My first question is about StackMaps: Is it true that llvm_gc_root_chain is an API? I've been trying to understand how exactly one accesses this structure and no where in the documentation does it mention this is a

Hello, list I am not quite sure if what I'm experiencing is a bug or intentional behavior. In the code below the result of a function call is a deopt arg to llvm.experimental.gc.statepoint (http://llvm.org/docs/Statepoints.html#llvm-experimental-gc-statepoint-intrinsic). Therefore a Stack Map containing location of this variable is created upon code generation. Here's the complete

On Thu, Jan 26, 2017 at 1:45 AM, Renato Golin <renato.golin at linaro.org> wrote: > On 26 January 2017 at 00:08, Kostya Serebryany via llvm-dev > <llvm-dev at lists.llvm.org> wrote: > > I want implement an instrumentation that gets the current PC. > > On x86_64 I can do it using inline asm (something like "lea (%%rip),%0"), > > but I wonder if there

On 31 Jan 2017 8:58 p.m., "Kostya Serebryany" <kcc at google.com> wrote: hmm. I am not sure I understood you. The last two paragraphs seem to contradict each other. So, you recommend to extend read_register to read the PC, or "read_register is locked at the stack pointer as a design decision"? Both. :-) There was a design decision to only support SP because we had no

On 26 January 2017 at 00:08, Kostya Serebryany via llvm-dev <llvm-dev at lists.llvm.org> wrote: > I want implement an instrumentation that gets the current PC. > On x86_64 I can do it using inline asm (something like "lea (%%rip),%0"), > but I wonder if there is some more LLVM-ish way to do it, e.g. an intrinsic? Hi Kostya, I'd also want something that GCC

On 27 March 2014 15:30, Rafael Espíndola <rafael.espindola at gmail.com> wrote: > For global ones, it should also codegen every non inline asm to use an > llvm intrinsic (llvm.read_register/llvm.write_register for example). That's my idea, yes. I'm not sure how Clang would transform the named registers into the intrinsic, but something along the lines of: i8* @SP =

On Tue, Jan 31, 2017 at 3:11 PM, Renato Golin <renato.golin at linaro.org> wrote: > On 31 Jan 2017 8:58 p.m., "Kostya Serebryany" <kcc at google.com> wrote: > > hmm. I am not sure I understood you. The last two paragraphs seem to > contradict each other. > So, you recommend to extend read_register to read the PC, or > "read_register is locked at the