1870396 - Use GuardFuse to speed up destructuring

Status: RESOLVED FIXED

(Core :: JavaScript Engine, enhancement, P3)

Description

[Matthew Gaudet (he/him) [:mgaudet]]

The initial machinery to use GuardFuse to optimize destructuring will land in Bug 1855301; this bug should track us actually turning on the optimized destructuring code.

Comment 1

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1870396 - Use a fuse check to speed up destructuring optimization r?jandem,iain

This speeds up a microbenchmark like the following by 33%.

function foo(x) {
    var b;
    [b] = x;
    return b;
}
let start = performance.now();
for (var i = 0; i < 200_000; i++) {
    foo([1, 2, 3]);
}
let end = performance.now();
console.log(end - start);

Comment 2

[Phabricator Automation]

Comment on attachment 9369241 [details]
Bug 1870396 - Use a fuse check to speed up destructuring optimization r?jandem,iain

Revision D194293 was moved to bug 1855301. Setting attachment 9369241 [details] to obsolete.

Comment 3

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1870396 - Add pref for fuse-guarded destructuring r?iain

Comment 4

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1870396 - Enable fuse-guarded destructuring optimization by default r?iain

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4665ed600ede
Enable fuse-guarded destructuring optimization by default r=iain
https://hg.mozilla.org/integration/autoland/rev/79a6322a49b2
Add pref for fuse-guarded destructuring r=iain

Comment 6

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/4665ed600ede
https://hg.mozilla.org/mozilla-central/rev/79a6322a49b2