On Fri, Nov 11, 2022 at 1:15 PM Filip Petronijevic < fpetronijevic661...@raf.rs> wrote:
> I treced down 'job' macro from tools/gdbinit and I found out it calls in > the end > https://source.chromium.org/chromium/chromium/src/+/main:v8/src/objects/objects.h;drc=a0dedabb214a245c792009e64baf333c7e8d7357;l=679 > > which is shortPrint. This still doesn't show me all level depths of an > object but rather first levels of representation and their > corresponding addresses. > Yes. > Do I have to manually go in these recursive depths or is there any better > way like to Stringify it? I'm trying to Stringify this *value *object > located in > https://source.chromium.org/chromium/chromium/src/+/main:v8/src/ic/ic.cc;l=1847;bpv=1;bpt=0?q=ic.cc&ss=chromium%2Fchromium%2Fsrc:v8%2F > but I have hard times converting it to a String > I don't know of a JSON.stringify equivalent for use in GDB. As I said, I'd inspect objects manually, level by level. If you find that you're spending too much time doing that, you could build your own tooling, e.g. a function that has a similar entry point as _v8_internal_Print_Object and internally wraps JsonStringify() and printf()s the result to stdout. > On Fri, Nov 11, 2022 at 12:26 PM Jakob Kummerow <jkumme...@chromium.org> > wrote: > >> Thanks! I found this StoreIC::Store() function just yesterday while >>> debugging in D8 and it works even without (--nouse-ic flag), even though I >>> have no clue what this flag does as I can't find it in docs. But this >>> tracks all of the keys and objects created. >> >> >> No, it won't catch all of them without the flag, but if it catches the >> ones you care about, that's good enough. >> >> >>> The main problem now is the following line of code in StoreIC::Store() >>> function ( >>> https://source.chromium.org/chromium/chromium/src/+/main:v8/src/ic/ic.cc;l=1847;bpv=1;bpt=0?q=ic.cc&ss=chromium%2Fchromium%2Fsrc:v8%2F >>> ) >>> >>> When I cast this object (value) into JSObject and do shortPrint or >>> PrintProperties() it doesn't take in account all properties if for example >>> its recursive object like this test: {test1: { test2: "testhelloworld" } } >>> but rather it prints just test and gives memory lolcation to test1. I can >>> obviously recursively do this, but is there any prittier way of doing this >>> like via some JSON stringify function? >>> >> >> I'd just inspect objects manually, using the `job` macro from >> tools/gdbinit. >> >> >>> I found such JSON stringify function here >>> https://source.chromium.org/chromium/chromium/src/+/main:v8/src/json/json-stringifier.h;bpv=1;bpt=0 >>> but I have very hard trouble in passing arguments to this function and >>> printing String out of it as it return MaybeHandle object. Any help here >>> would be appreciated. >>> >> >> Appending `.ToHandleChecked()` may be of use here (if the stringification >> doesn't throw), but yeah, invoking such functions in GDB tends to not work. >> >> >>> On Friday, November 11, 2022 at 11:47:33 AM UTC+1 Jakob Kummerow wrote: >>> >>>> Maps don't keep lists of the objects that use them. To find all objects >>>> that use a given map, you'd have to walk the entire heap to find all >>>> objects, and filter them by map. >>>> >>>> Considering your previous question, I'm not sure finding all objects >>>> that use a given map will actually be helpful. A possible way to intercept >>>> creation of properties with a given name (e.g. "mainkey") would be to run >>>> with `--nouse-ic` and put a breakpoint on StoreIC::Store(). This is >>>> (obviously?) not an officially supported feature, and I haven't tried it, >>>> so you may encounter obstacles or limitations of the approach, but it might >>>> at least get you a little further. >>>> >>>> I guess you'd need this in Chrome, not just d8, so the full workflow is: >>>> - build a Debug build of Chrome. Be sure to set v8_optimized_debug = >>>> false in args.gn beforehand. >>>> - run with each renderer in a debugger: out/debug/chrome --no-sandbox >>>> --disable-hang-monitor --disable-extensions --js-flags="--nouse-ic" >>>> --renderer-cmd-prefix="xterm -e gdb -args" >>>> - bring a large amount of patience to both of these steps, and have >>>> enough RAM in your machine (64GB is good, dunno if 32GB is enough) >>>> >>>> Good luck! >>>> >>>> >>>> On Wed, Nov 9, 2022 at 3:19 PM Filip Petronijevic <fpetronij...@raf.rs> >>>> wrote: >>>> >>>>> Ok, I'll explain what problem I have and if there is any way of >>>>> solving it. >>>>> >>>>> Imagine I have following Javascript code: >>>>> >>>>> var obj1= {} >>>>> obj1["mainkey"] = {canvasComputed: "oewrewqioewrerqewjoijiqerw", >>>>> todata: "somerandomdata"} >>>>> >>>>> var obj2= {} >>>>> obj2["mainkey"] = "some big string" >>>>> >>>>> var obj3 = {} >>>>> obj3['mainkey'] = {test: {test1:"somestring"}, test2: 3432} >>>>> >>>>> >>>>> I have 3 objects, they all share same Map. My question is if I know >>>>> what memory space this Map has, If I can use that to recursively find all >>>>> property values of all objects that share that same Map? In this case to >>>>> list obj1's property values (canvasComputed, toData), obj2 property values >>>>> (1 string) and obj3 property values(test object along with string >>>>> test2) >>>>> ? >>>>> >>>>> Or the only way I can list own properties of these objects is if I >>>>> know exact memory location of each of them? Is there any way I could >>>>> traverse from their Map or something they share in common (only mainkey >>>>> key) and use this fact to find all property values that hold mainkey as a >>>>> key? >>>>> >>>>> >>>>> When I do %DebugPrint(obj1) I can see its property values and that >>>>> this object shares same map as other objects, but I'm trying to find a way >>>>> to generalize this by starting from some common memory slot they all share >>>>> and traverse up recursively or whatever to get all property values? >>>>> >>>>> Best regards >>>>> >>>>> -- >>> >> -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. 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