[PATCH] D147013: [CSSPGO][Preinliner] Trim cold call edges of the profiled call graph for a more stable profile generation.

[Wenlei He via Phabricator via llvm-commits]

wenlei added inline comments.


================
Comment at: llvm/include/llvm/Transforms/IPO/ProfiledCallGraph.h:157
+      // Accumulate weight to the existing edge.
+      Edge.Weight += EdgeIt->Weight;
       Edges.erase(EdgeIt);
----------------
good catch


================
Comment at: llvm/tools/llvm-profgen/CSPreInliner.cpp:84
+  // profile from run to run.
+  uint64_t ColdCountThreshold = ProfileSummaryBuilder::getColdCountThreshold(
+      (Summary->getDetailedSummary()));
----------------
I understand that you want to do this only for preinliner, not for sample loader in compiler. But the current way of doing this - exposing internals of profiled calll graph only for users to tweak the actual graph, is less than idea as it breaks the abstraction. 

Can we have a separate parameter (i.e. hotCallonly) for ctor of ProfiledCallGraph, so this is all self contained? And perhaps slight more efficient as it avoids add and then removal. 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D147013/new/

https://reviews.llvm.org/D147013