1990510 - Add GVN for array bounds checks

Status: RESOLVED FIXED

(Core :: JavaScript: WebAssembly, enhancement)

Description

[Ben Visness [:bvisness]]

MWasmBoundsCheck has no congruentTo, which means that despite being totally GVN-able, bounds checks are not being GVN'd. This means, for example, that a load and store at the same index in a GC array will needlessly incur two bounds checks.

Comment 1

[Ben Visness [:bvisness]]

Attachment: Bug 1990510: Add congruentTo for MWasmBoundsCheck. r=rhunt

Two bounds checks on exactly the same values are obviously redundant and
can be GVN'd.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/3d0fa76548b7
https://hg.mozilla.org/integration/autoland/rev/27941f0ae914
Add congruentTo for MWasmBoundsCheck. r=rhunt

Comment 3

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/27941f0ae914