Hi Immanuel, this sounds like we should look into the generated code and look for missed optimizations. Can you open a bug about this via crbug.com/v8/new, and attach a reproducer? Ideally you could extract a small reproducer which contains the Wasm module and a JS snippet that shows the performance difference (you can read the wasm module via the `readbuffer` function in d8).
If you want to start investigating yourself, then a first step would be printing the generated machine code and looking at the disassembly. That requires a build with the "v8_enable_disassembler" gn arg set to "true" (default in a debug build). You can then run the reproducer with --print-wasm-code. To avoid also printing (and executing) the Liftoff code, which would not be interesting for peak performance, you can pass --no-liftoff. And to avoid concurrent compilation, which can mess up the output, you can pass --predictable. Cheers, Clemens On Tue, Apr 7, 2020 at 12:31 PM Immanuel Haffner <[email protected]> wrote: > And I should add that i don't see that behaviour for i64, float, or double. > > -- > -- > 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/53ea45d3-0c46-4a02-8d72-6e0bb14cf9f4%40googlegroups.com > <https://groups.google.com/d/msgid/v8-dev/53ea45d3-0c46-4a02-8d72-6e0bb14cf9f4%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- Clemens Backes Software Engineer [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/CAGO%3DqhCMGv%3DQec93VRY7pWmRC9CREDoth1%2B--BqNeGpUXnSwVA%40mail.gmail.com.
