[PGO] Allow collecting other kinds of pgo profiles.

[justinmichaud]

024fe2f

[PGO] Allow collecting other kinds of pgo profiles.
https://bugs.webkit.org/show_bug.cgi?id=239776

Reviewed by Saam Barati.

Update the way we collect PGO profiles to use LLVM's file handling, because
it really seems to care about that. This allowws us to try out other kinds
of profile generation, like the IR-based -fcs-profile-generate.

* Source/WTF/wtf/GenerateProfiles.h:
(WTF::registerProfileGenerationCallback):

Canonical link: https://commits.webkit.org/250064@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@293544 268f45cc-cd09-0410-ab3c-d52691b4dbfc

[saambarati]

Let's make this comment a bit more descriptive:
"If we export this symbol, LLVM won't run the static initializers for profiling."

[saambarati]

this can use makeString

[justinmichaud]

I have confirmed this works with the existing AST-based profiles, merging.

[webkit-early-warning-system]

Committed r293544 (250064@main): https://commits.webkit.org/250064@main

Reviewed commits have been landed. Closing PR #391 and removing active labels.