1677204 - Remove feature flags for shipped features and clean up feature logic

Status: RESOLVED FIXED

(Core :: JavaScript: WebAssembly, task, P3)

Description

[Ryan Hunt [:rhunt]]

It looks like wasm multi-value and reftypes are now supported by all compilers and we can start to remove the feature flag functionality here.

Comment 1

[Lars T Hansen [:lth]]

rs=me!

Comment 2

[Ryan Hunt [:rhunt]]

Attachment: Bug 1677204 - wasm: Remove multi-value flag. r?lth

Multi-value has shipped and can remove its feature flag.

Comment 3

[Ryan Hunt [:rhunt]]

Attachment: Bug 1677204 - wasm: Factor out feature gating to declarative macro. r?lth

This commit adds a declarative JS_FOR_WASM_FEATURES macro which
expands for every WebAssembly proposal we are gating. Most feature
gating code is refactored to use this macro so that we have one place
we need to change to get the majority of this code working. The only
place that needs to be updated for new features is the browser pref
declaration code, as that cannot use this macro. This is documented
in the new WasmFeatures.h header.

The feature gating logic should work almost identically as before.
The changes are:

• All browser prefs are moved to StaticPrefList.yaml
• The code to enable a feature was conditionally compiled to not
  enable the feature at variously stages of the "flag-flow". Now
  the only place that is conditionally compiled to not work is
  in the WasmXFlag functions. This is to make the macro simpler
  and might be able to be reverted if need be.
• The flag for gc is shortened from gcTypes to gc so that the
  existing usages of the wasmGcEnabled shell function don't have
  to change.

This commit also has the effect of giving function-references/gc/
exception-handling a proper browser pref for enabling the features.

Depends on D110819

Comment 4

[Ryan Hunt [:rhunt]]

Attachment: Bug 1677204 - wasm: Expand feature enablement testing for active proposals. r?lth

The features.js test could use some updates for the current active/shipped
proposals.

Depends on D110820

Comment 5

[Ryan Hunt [:rhunt]]

Attachment: Bug 1677204 - wasm: Gate event section on exception-handling flag. r?lth

Only allow decoding the event section when exception-handling is enabled.

Depends on D110821

Comment 6

[Ryan Hunt [:rhunt]]

Attachment: Bug 1677204 - wasm: Remove reftypes flag. r?lth

Reftypes has shipped and so we can remove the feature flag.

Depends on D110822

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/74f706489769
wasm: Remove multi-value flag. r=lth
https://hg.mozilla.org/integration/autoland/rev/e4aa0aabc24d
wasm: Factor out feature gating to declarative macro. r=lth
https://hg.mozilla.org/integration/autoland/rev/656d9d64fee1
wasm: Expand feature enablement testing for active proposals. r=lth
https://hg.mozilla.org/integration/autoland/rev/d0073c38f10b
wasm: Gate event section on exception-handling flag. r=lth
https://hg.mozilla.org/integration/autoland/rev/f89e1e839deb
wasm: Remove reftypes flag. r=lth

Comment 8

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/74f706489769
https://hg.mozilla.org/mozilla-central/rev/e4aa0aabc24d
https://hg.mozilla.org/mozilla-central/rev/656d9d64fee1
https://hg.mozilla.org/mozilla-central/rev/d0073c38f10b
https://hg.mozilla.org/mozilla-central/rev/f89e1e839deb