Still hoping to get some guidance with this. I'm also interested in support, even if limited, for string value parameters (or even return values) and returning of TypedArray buffers. Though, I expect those to be much harder to implement than returning External objects for void pointers. I guess a somewhat related option is to return external pointers as zero-sized TypedArrays / ArrayBuffers, but that sounds quite wrong compared to External objects.
On Friday, 23 September 2022 at 15:15:10 UTC+3 Aapo Alasuutari wrote: > I presume Maya might now be back be at the office? > > Would it be possible to get some guidance regarding implementing void > pointer support, either here on Groups or possibly by organizing an online > meeting of some sort? > > -Aapo > > On Tuesday, 23 August 2022 at 11:32:30 UTC+3 cbr...@chromium.org wrote: > >> Hi, yes, Maya is out until mid-september. >> Cheers, Camillo >> >> On Tue, 23 Aug 2022 at 07:07, Aapo Alasuutari <aapo.al...@gmail.com> >> wrote: >> >>> Has Maya possibly returned from vacation? Or is their leave still >>> continuing? >>> >>> On Friday, 29 July 2022 at 12:08:53 UTC+3 ah...@google.com wrote: >>> >>>> Maya is on leave over the summer, unfortunately. >>>> >>>> On Fri, Jul 29, 2022 at 11:02 AM Leszek Swirski <les...@chromium.org> >>>> wrote: >>>> >>>>> +Maya, you're probably the best person to answer this. >>>>> >>>>> On Tue, Jul 26, 2022 at 9:05 PM Aapo Alasuutari <aapo.al...@gmail.com> >>>>> wrote: >>>>> >>>>>> Hello, >>>>>> >>>>>> I'm interested in implementing `void*` pointer support for Fast API >>>>>> calls. My thinking was that V8's `External` objects are appropriate to >>>>>> stand in for external `void*` pointers coming in from external code and >>>>>> going back out, since that's what they're (presumably) meant for. >>>>>> >>>>>> Unfortunately this seems to be a complex endeavour, a bit more than I >>>>>> can start hacking together directly. I'm also not sure if the >>>>>> `Sandboxify >>>>>> JSExternalObject external pointer` PR will complicate this plan of mine. >>>>>> >>>>>> The origin of my interest is Deno FFI support, that is calling native >>>>>> libraries from Deno JS runtime that uses the V8 engine. Recent changes >>>>>> to >>>>>> the FFI have added V8 Fast API support and made the FFI a lot faster, >>>>>> but >>>>>> unfortunately we're bound to using plain numbers as pointers, meaning >>>>>> both >>>>>> that creating pointers is as easy as just writing a number and that >>>>>> (Fast >>>>>> API compatible) pointers are limited to 53 bit numbers which will not be >>>>>> enough for eg. pointer cryptography on ARM v8.3. >>>>>> >>>>>> It believe it would be preferable if Deno could use `External` >>>>>> objects to stand for pointers but this would negate the current Fast API >>>>>> performance benefits. Thus, `void*` pointer support for fast calls. >>>>>> >>>>>> >>>>>> Any comments? Suggestions on how I might best proceed with this to >>>>>> implement it? Or is this perhaps not a reasonable idea? >>>>>> >>>>>> Side note: I was sad to find that getting the pointer value out of an >>>>>> `Local<External>` is measurably slower than getting the pointer number >>>>>> value out of a `Local<Number>`. This is presumably due to the `External` >>>>>> internally saving the pointer in the `ExternalMap`. The slower >>>>>> performance >>>>>> is still a bit sad, from having expected `External` to be the main >>>>>> public >>>>>> API meant to handle external pointers. >>>>>> >>>>>> -- >>>>>> -- >>>>>> v8-dev mailing list >>>>>> v8-...@googlegroups.com >>>>>> http://groups.google.com/group/v8-dev >>>>>> --- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "v8-dev" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to v8-dev+un...@googlegroups.com. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/v8-dev/a4914444-88bf-4238-828c-9ec3f2e09878n%40googlegroups.com >>>>>> >>>>>> <https://groups.google.com/d/msgid/v8-dev/a4914444-88bf-4238-828c-9ec3f2e09878n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>> -- >>>>> -- >>>>> v8-dev mailing list >>>>> v8-...@googlegroups.com >>>>> http://groups.google.com/group/v8-dev >>>>> --- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "v8-dev" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to v8-dev+un...@googlegroups.com. >>>>> >>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/v8-dev/CAGRskv_o%3DdZTXdYAceSM%2BdaabpJKFYZwEFMjvzS3_8jy3e0TuQ%40mail.gmail.com >>>>> >>>>> <https://groups.google.com/d/msgid/v8-dev/CAGRskv_o%3DdZTXdYAceSM%2BdaabpJKFYZwEFMjvzS3_8jy3e0TuQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- >>> -- >>> v8-dev mailing list >>> v8-...@googlegroups.com >>> http://groups.google.com/group/v8-dev >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "v8-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to v8-dev+un...@googlegroups.com. >>> >> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/v8-dev/17c3b560-e88d-41a7-b64d-d792b4021613n%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/v8-dev/17c3b560-e88d-41a7-b64d-d792b4021613n%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> Camillo Bruni | Software Engineer, V8 | Google Germany GmbH | Erika-Mann >> Str. 33, 80636 München >> >> Registergericht und -nummer: Hamburg, HRB 86891 | Sitz der Gesellschaft: >> Hamburg | Geschäftsführer: Paul Manicle, Halimah DeLaine Prado >> >> Diese E-Mail ist vertraulich. Falls Ssie diese fälschlicherweise erhalten >> haben sollten, leiten Sie diese bitte nicht an jemand anderes weiter, >> löschen Sie alle Kopien und Anhänge davon und lassen Sie mich bitte wissen, >> dass die E-Mail an die falsche Person gesendet wurde. This e-mail is >> confidential. If you received this communication by mistake, please don't >> forward it to anyone else, please erase all copies and attachments, and >> please let me know that it has gone to the wrong person. >> > -- -- v8-dev mailing list v8-dev@googlegroups.com http://groups.google.com/group/v8-dev --- You received this message because you are subscribed to the Google Groups "v8-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-dev+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/v8-dev/1111ab24-1132-4752-ba60-130d658a2892n%40googlegroups.com.
