[PATCH] D15828: [PGO] Passmanagerbuilder change that enable IR level PGO instrumentation

[Chandler Carruth via llvm-commits]

chandlerc added a subscriber: chandlerc.

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Comment at: lib/Transforms/IPO/PassManagerBuilder.cpp:281
@@ -239,1 +280,3 @@
 
+  addPGOInstrPasses(MPM);
+
----------------
davidxl wrote:
> joker.eph wrote:
> > There will be an inliner SCC pass manager created in the PGO InstrPasses. It is not clear to me why you don't integrate this with the regular inliner a few line below.
> This is the pre-inline pass that needs to happen before instrumentation. See the original RFC: http://lists.llvm.org/pipermail/llvm-dev/2015-August/089425.html for details.
Yes, and there was not consensus in the RFC for the pre-inlining. Instead, the approach suggested was to work on independent components which seem non-controversial and have a separate focused discussion about pre-inlining and other interactions.

I think there are still a lot of unanswered questions around the pre-inlining phase (based on my reading of the RFC thread you pointed at). If there is some other thread that I've not seen, feel free to direct there...


http://reviews.llvm.org/D15828