[LLVMdev] Removing AvailableExternal values in GlobalDCE (was Re: RFC: ThinLTO Impementation Plan)

[David Chisnall]

On 8 Jun 2015, at 21:08, Eric Christopher <echristo at gmail.com> wrote:
> 
> I'd rather not have it be an llvm option at all. Just construct a different set of passes...
> 
> This would also solve the problem of needing multiple sets of options to be passed to the builder. It'd be a bit of a change (i.e. having clang do the pass setup), but I think it'd be worth it to have clang be able to explicitly say which passes it wants.

There’s some value in making it possible for clang and opt to run the same set of passes.  It’s also nice to be able to provide libraries that can inject passes at specific points in the optimisation sequence (this was one of the design goals of PassManagerBuilder) without needing to modify every front end that might use them.

David