chandlerc added a comment.

In D63155#1563229 <https://reviews.llvm.org/D63155#1563229>, @xur wrote:

> This patch does not make sense to me.
>
> The reason of failing with -fexperimental-new-pass-manager is because we 
> don't do PGO instrumentation at -O0. This is due to the fact that PGO 
> instrumentation/use passes are under 
> PassBuilder::buildPerModuleDefaultPipeline.
>
> This patch add a pass
>
>   MPM.addPass(PGOInstrumentationGenCreateVar(PGOOpt->ProfileFile));
>
> which only gives you the wrong signal  of instrumentation is done.
>
> I wrote pass PGOInstrumentationGenCreateVar only for some trick interactions 
> for thinlto under ldd for CSPGO.
>  Regular FDO should not use it.
>
> The right fix is to enable PGO instrumentation and use in pass builder for O0.
>
> I would like to request to revert this patch.


I mean, I'm happy for the patch to be reverted, but I still really don't 
understand why this fixes the test to work *exactly* the same as w/ the old 
pass manager and doesn't break any other tests if it is completely wrong? It 
seems like there must be something strange with the test coverage if this is so 
far off of correct without any failures...

I also don't understand what fix you are suggesting instead, but maybe you can 
show a patch?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D63155/new/

https://reviews.llvm.org/D63155



_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to