Thanks for the answers! LGTM1. On Wed, Mar 26, 2025 at 7:25 PM Emanuel Ziegler <ecmzieg...@chromium.org> wrote:
> Ah, I looked in the wrong "binary" rendering of the spec. This is the > correct link: > https://webassembly.github.io/branch-hinting/metadata/code/binary.html > (yes, it's extremely simple) > I updated the link in the feature. Sorry for the confusion! > > On Wed, Mar 26, 2025 at 10:31 AM Emanuel Ziegler <ecmzieg...@chromium.org> > wrote: > >> See answers below. Thanks! >> >> On Wed, Mar 26, 2025 at 2:26 AM Domenic Denicola <dome...@chromium.org> >> wrote: >> >>> >>> >>> On Tue, Mar 25, 2025 at 9:49 PM Emanuel Ziegler <ecmzieg...@chromium.org> >>> wrote: >>> >>>> Hi all, >>>> >>>> We are preparing to ship the WebAssembly Branch Hints proposal in M136 >>>> which has been voted to phase 4 in the Wasm Community Group last July. >>>> Chrome is now catching up with shipping it after requests from partners. >>>> The feature is already implemented in Firefox. >>>> >>>> The proposal was championed by Yuri Iozzelli from Leaning Technologies >>>> and the V8 team was not involved in its standardization process. The >>>> implementation has no effect on existing code by design which is why a >>>> Finch trial would not yield any insights. We have a Chromium feature >>>> available for a Finch kill-switch if necessary. >>>> >>>> Thank you, >>>> Emanuel >>>> >>>> >>>> Contact emailsecmzieg...@chromium.org, jkumme...@chromium.org >>>> >>>> ExplainerNone >>>> >>>> Specification >>>> https://github.com/WebAssembly/branch-hinting/blob/main/proposals/branch-hinting/Overview.md >>>> >>> >>> It seems like you put the explainer in the specification field, and >>> didn't link to the specification. I guess the spec is at >>> https://github.com/WebAssembly/branch-hinting/blob/main/document/core/appendix/custom.rst >>> ? Although I'm not sure the rendering there is quite right... is there a >>> better URL? >>> >> >> Unfortunately, the rendered content has not been updated in a while and >> this is the only source of truth until the spec is fully merged into the >> Wasm spec. >> >> >>> Summary >>>> >>>> Improves the performance of compiled WebAssembly code by informing the >>>> engine that a particular branch instruction is very likely to take a >>>> specific path. This allows the engine to make better decisions for code >>>> layout (improving instruction cache hits) and register allocation. >>>> https://github.com/WebAssembly/branch-hinting/blob/main/proposals/branch-hinting/Overview.md >>>> >>>> >>>> Blink componentBlink>JavaScript>WebAssembly >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EJavaScript%3EWebAssembly%22> >>>> >>>> TAG reviewNone >>>> >>>> TAG review statusNot applicable >>>> >>> >>>> >>>> Risks >>>> >>>> >>>> Interoperability and Compatibility >>>> >>>> None >>>> >>> >>> Can you expand on why you believe there are no interop and compat risks? >>> >> >> This is a fully optional proposal without any difference in >> functionality. If an engine does not support it, it will simply run the >> code a little slower. >> >> *Gecko*: No signal >>>> >>>> *WebKit*: No signal >>>> >>> >>>> *Web developers*: No signals >>>> >>>> *Other signals*: >>>> >>>> WebView application risks >>>> >>>> Does this intent deprecate or change behavior of existing APIs, such >>>> that it has potentially high risk for Android WebView-based applications? >>>> >>>> None >>>> >>>> >>>> Debuggability >>>> >>>> None >>>> >>>> >>>> Will this feature be supported on all six Blink platforms (Windows, >>>> Mac, Linux, ChromeOS, Android, and Android WebView)?No >>>> >>> >>> Why not? >>> >> >> Sorry, that was a mistake and has been fixed. We are planning on shipping >> it everywhere since the changes are not architecture dependent. >> >> >>>> Is this feature fully tested by web-platform-tests >>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>>> ?No >>>> >>> >>> Why not? >>> >> >> Because there is no observable behavior change that could be tested >> against. >> >> >>> Flag name on about://flagsNone >>>> >>>> Finch feature nameV8Flag_experimental_wasm_branch_hinting >>>> >>>> Requires code in //chrome?False >>>> >>>> Estimated milestones >>>> Shipping on desktop 136 >>>> Shipping on Android 136 >>>> Shipping on WebView 136 >>>> >>>> Anticipated spec changes >>>> >>>> Open questions about a feature may be a source of future web compat or >>>> interop issues. Please list open issues (e.g. links to known github issues >>>> in the project for the feature specification) whose resolution may >>>> introduce web compat/interop risk (e.g., changing to naming or structure of >>>> the API in a non-backward-compatible way). >>>> None >>>> >>>> Link to entry on the Chrome Platform Status >>>> https://chromestatus.com/feature/5165273114738688?gate=5186994509185024 >>>> >>>> This intent message was generated by Chrome Platform Status >>>> <https://chromestatus.com/>. >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "blink-dev" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to blink-dev+unsubscr...@chromium.org. >>>> To view this discussion visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAPAU7RwMXE%2BnsewWqSQ0M%2BS7gH600KjJtnp2T3Oyw8GPz4nNHg%40mail.gmail.com >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAPAU7RwMXE%2BnsewWqSQ0M%2BS7gH600KjJtnp2T3Oyw8GPz4nNHg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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