1703469 - Optimize calls to polymorphic scripted getters/setters better

Status: NEW

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

Description

[Jan de Mooij [:jandem]]

After bug 1700052, getter/setter IC stubs still optimize for a single getter/setter object, but we could now change that to load the getter or setter object from the GetterSetter and guard on its BaseScript (or handle any scripted function), similar to normal calls.

We probably don't want to do this always because this guard would be a bit slower than what we do now, but maybe when we're attaching a stub other than the first one we could use the slower guard that handles more cases (similar to normal calls).

It might also make sense to have a shape attribute indicating whether the accessors are scripted functions, so that we don't need to guard on the JSClass in the common case.