[llvm] [llvm-profgen] Filter out ambiguous cold profiles during profile generation (PR #81803)

[via llvm-commits]

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@@ -491,6 +518,7 @@ void ProfileGenerator::generateProfile() {
 void ProfileGenerator::postProcessProfiles() {
   computeSummaryAndThreshold(ProfileMap);
   trimColdProfiles(ProfileMap, ColdCountThreshold);
+  filterAmbiguousProfile(ProfileMap);
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WenleiHe wrote:

Please comment why we need to filter.

https://github.com/llvm/llvm-project/pull/81803