1546383 - Add CacheIR support for calling getters on primitive values

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, enhancement, P1)

Description

[André Bargull [:anba]]

Neither Ion nor CacheIR support calling getters on primitive values, which makes the access to Symbol.prototype.description really slow in comparison to JSC and V8. As a first step we should add CacheIR support here.

µ-benchmark:

if (typeof dateNow === "undefined") {
  if (typeof preciseTime === "function") {
    dateNow = () => preciseTime() * 1000;
  } else if (typeof performance === "object" && typeof performance.now ===
"function") {
    dateNow = performance.now;
  } else {
    dateNow = Date.now;
  }
}

function f() {
    var xs = [
        Symbol(""),
        Symbol(""),
    ];
    var q = 0;
    var t = dateNow();
    for (var i = 0; i < 1000000; ++i) {
        q += xs[i & 1].description.length;
    }
    return [dateNow() - t, q]
}

Engine	Time
SM	~300ms
SM (with patch)	25ms
JSC	12ms
V8	8ms

Comment 1

[André Bargull [:anba]]

Attachment: Bug 1546383: Add CacheIR support for calling getters on primitive values. r=mgaudet!

Comment 2

[André Bargull [:anba]]

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=b8c886c458f7a0f5d2b76df65de51cce5c58a894

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1f47ae47ceac
Add CacheIR support for calling getters on primitive values. r=mgaudet

Comment 4

[Dorel Luca [:dluca]]

Backed out changeset 1f47ae47ceac (bug 1546383) for Spidermonkey failures in js\src\jit-test\tests\cacheir\getter-primitive-value.js. CLOSED TREE

Log:
https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=244938670&repo=autoland&lineNumber=13495

Push with failures:
https://treeherder.mozilla.org/#/jobs?repo=autoland&revision=1f47ae47ceacd9bb1df12c3dd8987b93bd44f608

Backout:
https://hg.mozilla.org/integration/autoland/rev/f776e9e5e817c9f1acd0451e915042089e80ce14

Comment 5

[André Bargull [:anba]]

Running the builds linked at comment #4 locally, I see the following assertion:

C:\Users\andre\Downloads\target.jsshell>js.exe --ion-eager ..\cacheir-getter-primitive.js
Assertion failure: !availableRegs_.empty(), at z:/build/build/src/js/src/jit/CacheIRCompiler.cpp:422

So there are too few registers available on 32-bit builds. New try build: https://treeherder.mozilla.org/#/jobs?repo=try&revision=d72f1838dd432fbfbdd65c9ddd672552942d06f2

Comment 6

[André Bargull [:anba]]

Try from comment #5 was successful.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/15178f63cc19
Add CacheIR support for calling getters on primitive values. r=mgaudet

Comment 8

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/15178f63cc19