1261726 - Eliminate s{Methods,Attributes,...}_ids in generated DOM bindings code

Status: RESOLVED WORKSFORME

(Core :: DOM: Bindings (WebIDL), defect, P3)

Description

[Nicholas Nethercote [inactive]]

All the *_ids arrays in generated DOM bindings code currently take up 80+ KiB
on 64-bit builds.

They are used in two places of note.

First, in XrayResolveAttribute() and XrayResolveMethod(). We use them for the
"here is a jsid; find our corresponding JSPropertySpec or JSFunctionSpec"
operation. We walk along the *_ids array checking for equality with the given
id until we find the right index; we then use that to index into the
JSFunctionSpec* or JSPropertySpec*. We could just walk the
JSFunctionSpec*/JSPropertySpec* directly if we had a fast-ish way to compare a
given jsid to the strings in those specs.

Second, in XrayAttributeOrMethodKeys(), which produces all the ids involved.
We could instead just create them from strings as we go. It'd only be hit when
someone enumerates an Xray or does Object.getOwnPropertyNames on it, which
probably isn't common. We would need some API for turning a string in a
JSPropertySpec/JSFunctionSpec.

Comment 1

[Boris Zbarsky [:bzbarsky]]

Note that some of the discussion in bug 786819 suggests ditching the strings from the specs and using the ids instead...  Not clear how this would work on workers.

Comment 2

[Nicholas Nethercote [inactive]]

s{Methods,Attributes,...}_ids no longer exist, so this bug is moot.