1910423 - Implement Float64 -> Float16 conversion with inline assembly

Status: RESOLVED FIXED

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

Description

[André Bargull [:anba]]

Implement Float64 -> Float16 conversion without a call using the technique linked from https://github.com/tc39/proposal-float16array/issues/12#issuecomment-2026271444.

Comment 1

[André Bargull [:anba]]

Attachment: Bug 1910423 - Part 1: Support encoding vpsignd instruction. r=jandem!

Used in the next part because it gives a noticeable performance boost
when we can avoid extra GPR<>XMM register moves.

Comment 2

[André Bargull [:anba]]

Attachment: Bug 1910423 - Part 2: Add inline Float64 -> Float16 conversion through Float32. r=jandem!

Add an inline assembly path to convert Float64 directly to Float16 without a call
into the runtime. Doubles the performances when converting a double to float16.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e3b75650396f
Part 1: Support encoding vpsignd instruction. r=jandem
https://hg.mozilla.org/integration/autoland/rev/988852519e9f
Part 2: Add inline Float64 -> Float16 conversion through Float32. r=jandem

Comment 4

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/e3b75650396f
https://hg.mozilla.org/mozilla-central/rev/988852519e9f