[PATCH] D26437: Use -fno-unit-at-a-time and -funit-at-a-time

[Teresa Johnson via llvm-commits]

tejohnson added a comment.

In https://reviews.llvm.org/D26437#593538, @rampitec wrote:

> In https://reviews.llvm.org/D26437#593492, @tejohnson wrote:
>
> > In what way is this different from the IPO we do on single source files at -O2? It should be conservatively correct.
>
>
> Such IPO has to be limited to non-external functions only then. That does not seem to be the case.


They should be correctly limited in the case of externally visible functions. Otherwise -O2 would be failing.  E.g. GlobalOpt that you mentioned earlier is only going to remove unreferenced functions that are local or otherwise discardable (linkonce, available_externally linkages types).

Do you have an example where one of these passes is doing the wrong thing?


Repository:
  rL LLVM

https://reviews.llvm.org/D26437