1701895 - Ensure stub fields are properly aligned

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, task, P3)

Description

[Jan de Mooij [:jandem]]

On 32-bit platforms we have two stub field sizes, 4 bytes and 8 bytes. We should ensure the 8-byte fields are aligned to 8 bytes.

This likely isn't an actual problem (we rely on unaligned accesses in other places) but with the changes in bug 1700052 we'll be using more Value stub fields so it would be nice to fix this.

Comment 1

[Jan de Mooij [:jandem]]

Attachment: Bug 1701895 - Ensure stub fields are properly aligned on 32-bit. r?iain!

• In CacheIRWriter::copyStubData, assert stub fields are aligned based on their size.
• On 32-bit platforms, add padding to ICCacheIRStub and IonICStub to ensure stub data is aligned to 8 bytes.
• On 32-bit platforms, insert a padding field in CacheIRWriter::addStubField if necessary.
• Fix alignment assertions in CacheIRStubInfo methods to include the offset.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/528b3f389dc9
Ensure stub fields are properly aligned on 32-bit. r=iain

Comment 3

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/528b3f389dc9