[llvm] [WPD] Reduce ThinLTO link time by avoiding unnecessary summary analysis (PR #164046)

[Teresa Johnson via llvm-commits]

teresajohnson wrote:

> > Note that we previously took the last conforming vtable summary, and now
> > we use the first. This caused a test difference in one somewhat
> > contrived test for vtables in comdats.
> 
> IIUC this is an artifact of `llvm-lto2 run %t3.o %t4.o` and summary iteration order.
> 
> Before this change the loop uses the last summary, and after this change the loop exits after finding the first summary, so WAI (the `break` takes effect).

Correct.

https://github.com/llvm/llvm-project/pull/164046