1903539 - Followups to bug 1891182 (refactoring of ModuleGenerator and ModuleEnvironment)

Status: RESOLVED FIXED

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

Description

[Julian Seward [:jseward]]

The following cleanup items resulting from bug 1891182 need to be done:

(2) = higher priority, (3) = lower priority
CM = CodeMetadata, MM = ModuleMetadata

• move
  (3) CM::codeSection to MM
  (3) CM::customSectionRanges to MM (maybe complexity with Decoder)
  (2) Module::{dataSegments_, elemSegments_, customSections_} to MM

• (2-3) assess the costs of passing around RefPtr<CM/MM> rather than
  plain CM*/MM*; fix if needed

• (2)
  space accounting:
  fix CodeMetadata::sizeOfExcludingThis (if it needs fixing)
  fix CodeMetadataForAsmJS::sizeOfExcludingThis (maybe?)
  fix Module::initGCMallocBytesExcludingCode
  Module::addSizeOfMisc: move imports_/exports_ accounting to MM

• (2) wasm::CompileTier2: why does this create a ModuleMetadata?
  (also .. and a CodeMetadata?) Neither is necessary.
  -- this is a nasty tangle

• (3) give MM a RefPtr to CM

Comment 1

[Julian Seward [:jseward]]

Attachment: Bug 1903539 - part 01 - move Module::{dataSegments_, elemSegments_, customSections_} to ModuleMetadata. r=rhunt.

This patch removes Module::{dataSegments_, elemSegments_, customSections_} and
adds ModuleMetadata::{dataSegments, customSections} instead.
ModuleMetadata::elemSegments already exists but was only used during module
generation.

The new code does the obvious thing -- those fields now live permanently in
ModuleMetadata. This was mostly straightforward, apart from a bit of
hoop-jumping in the deserializer, due to a circular dependency: Code must be
deserialized before ModuleMetadata so as to make types available, but Code
needs to have its codeMeta().nameCustomSectionIndex field set by using info
from ModuleMetadata.

A few comments have been tidied up.

Comment 2

[Julian Seward [:jseward]]

Attachment: Bug 1903539 - part 02 - fix up memory reporting methods following bug 1891182. r=rhunt.

Bug 1891182 majorly mashed around source metadata management for wasm and
asm.js, resulting in breakage to various memory reporter routines. This patch
is a best-effort attempt to fix up sizeOfExcludingThis() for
CodeMetadataForAsmJSImpl, CodeMetadata and ModuleMetadata.
Module::initGCMallocBytesExcludingCode has also been changed.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f6e5093b8775
part 01 - move Module::{dataSegments_, elemSegments_, customSections_} to ModuleMetadata.  r=rhunt.
https://hg.mozilla.org/integration/autoland/rev/2f5cd98ee842
part 02 - fix up memory reporting methods following bug 1891182.  r=rhunt.

Comment 4

[tszentpeteri]

https://hg.mozilla.org/mozilla-central/rev/f6e5093b8775
https://hg.mozilla.org/mozilla-central/rev/2f5cd98ee842