The core realization is that relying on "just using LLDB" is not going to give us the kind of seamless debugging experience that we hope to get for the web (in Chromium DevTools), since LLDB insists to sit on the driver seat. Instead we are thinking of a solution here were we use the *single debugger* built into the JS/Wasm (i.e. the V8 debugger), and have that manage all the breakpoints, control the stepping, and also manage the call stacks. The language components (which might use parts of LLDB if necessary) will only be responsible to help the debugger translate locations and expressions between source and target language. So, yes, we're essentially looking to replace LLDB with our own debugger.
Note: This is solely thinking about the Chromium DevTools Frontend use case for now. For standalone Wasm purposes, LLDB looks like a very good (and probably the best) solution. cheers, Benedikt On Mon, Oct 14, 2019 at 10:23 AM Philip Pfaffe <[email protected]> wrote: > Hi everyone, > > just to be sure I fully understand the plan. We intend to wrap LLDB (or > more specifically, the wasm debug module, which then wraps LLDB) inside a > language component which connects with the devtools frontend through CDP? > Or are we looking to replace LLDB with our own debugger interpretation? > > Best regards, > Philip > > On Fri, Oct 11, 2019 at 8:51 AM Benedikt Meurer <[email protected]> > wrote: > >> Hey folks, >> >> Following up on the prototyping work around Wasm Debugging with LLDB, >> we're starting to realize that it might not work out to just pull in LLDB >> combined with DWARF to create an excellent Wasm debugging experience. What >> we are looking for in the end is a solution, where DevTools is able to >> debug applications consisting of various JavaScript and WebAssembly parts >> seamlessly. Based on the current experiments (thanks a lot to the folks >> that ran the experiments here, which helped a lot to gain a better >> understanding of the problem space) it seems that full LLDB is always going >> to assume that *it's driving the car*, when in reality the JavaScript >> engines debugger has to *drive the car* in order to make the whole thing >> work across language barriers. >> > Following along this thought we realized that for modern JavaScript we >> already have very similar problems to WebAssembly. I.e. the code that the >> application is written in is usually not the code that the browser engines >> sees. And the current solution here - which is source maps - is far from >> sufficient to address this issue. >> >> This brought us to consider the idea of language servers, which has been >> proposed before, as a way to make forward progress here. Some discussions >> have already happened around this, but I'd like to make sure to include >> everyone here from the beginning, so I created an initial design proposal ( >> http://bit.ly/devtools-language-servers), so let's use that as a basis >> for further discussion. In essence it describes two possible high level >> solutions how to address the current problem. >> >> Please let me know what you think. >> cheers, >> Benedikt >> >> -- >> >> Benedikt Meurer >> >> Chromium DevTools TL >> >> [email protected] >> >> Google Germany GmbH >> >> Erika-Mann-Straße 33 >> >> 80636 München >> >> Geschäftsführer: Paul Manicle, Halimah DeLaine Prado >> >> Registergericht und -nummer: Hamburg, HRB 86891 >> >> Sitz der Gesellschaft: Hamburg >> >> Diese E-Mail ist vertraulich. Falls sie 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. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "devtools-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/a/chromium.org/d/msgid/devtools-dev/CAGowDna6zOniX3Svj3z8AJHzPo%3DOgumGkOPLBNdieqjsPTWrHQ%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/devtools-dev/CAGowDna6zOniX3Svj3z8AJHzPo%3DOgumGkOPLBNdieqjsPTWrHQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to a topic in the > Google Groups "devtools-dev" group. > To unsubscribe from this topic, visit > https://groups.google.com/a/chromium.org/d/topic/devtools-dev/X0bwUUmCajo/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/devtools-dev/CANncsuorOHi0kqhZBrw1Q2FFpNebJmqPYkFYr-trn1sGkzNCVw%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/devtools-dev/CANncsuorOHi0kqhZBrw1Q2FFpNebJmqPYkFYr-trn1sGkzNCVw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- Benedikt Meurer Chromium DevTools TL [email protected] Google Germany GmbH Erika-Mann-Straße 33 80636 München Geschäftsführer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg Diese E-Mail ist vertraulich. Falls sie 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 [email protected] 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/v8-dev/CAGowDnZDSSi07vHRcA%2B1WLix_c0m66_YNJTiQWNYjZgedbPdDw%40mail.gmail.com.
