LGTM3 On Thu, Mar 27, 2025 at 7:54 AM Mike Taylor <miketa...@chromium.org> wrote:
> LGTM2 > On 3/26/25 9:37 PM, Domenic Denicola wrote: > > 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 emails ecmzieg...@chromium.org, jkumme...@chromium.org >>>>> >>>>> Explainer None >>>>> >>>>> 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 component Blink>JavaScript>WebAssembly >>>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EJavaScript%3EWebAssembly%22> >>>>> >>>>> TAG review None >>>>> >>>>> TAG review status Not 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://flags None >>>>> >>>>> Finch feature name V8Flag_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. > 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/CAM0wra-gZUpEw-aoxUssO7_ezK6UCE9pvYR%2B%3D1OdWHXTEjtnfg%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAM0wra-gZUpEw-aoxUssO7_ezK6UCE9pvYR%2B%3D1OdWHXTEjtnfg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > -- > 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/40a923d7-ce21-44c5-914c-1ec59d8ee5af%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/40a923d7-ce21-44c5-914c-1ec59d8ee5af%40chromium.org?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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