[llvm] [profdata] Use --hot-func-list to show all hot functions (PR #149428)

[Mingming Liu via llvm-commits]

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@@ -3034,16 +3019,26 @@ static int showInstrProfile(ShowFormat SFormat, raw_fd_ostream &OS) {
        << "): " << PS->getNumFunctions() - BelowCutoffFunctions << "\n";
   }
 
+  // Sort by MaxCount in decreasing order
+  llvm::stable_sort(NameRefAndMaxCount, [](const auto &L, const auto &R) {
+    return L.second > R.second;
+  });
   if (TopNFunctions) {
-    std::vector<std::pair<std::string, uint64_t>> SortedHottestFuncs;
-    while (!HottestFuncs.empty()) {
-      SortedHottestFuncs.emplace_back(HottestFuncs.top());
-      HottestFuncs.pop();
-    }
     OS << "Top " << TopNFunctions
        << " functions with the largest internal block counts: \n";
-    for (auto &hotfunc : llvm::reverse(SortedHottestFuncs))
-      OS << "  " << hotfunc.first << ", max count = " << hotfunc.second << "\n";
+    auto TopFuncs = ArrayRef(NameRefAndMaxCount).take_front(TopNFunctions);
+    for (auto [NameRef, MaxCount] : TopFuncs)
+      OS << "  " << Reader->getSymtab().getFuncOrVarName(NameRef)
+         << ", max count = " << MaxCount << "\n";
+  }
+
+  if (ShowHotFuncList) {
+    auto HotCountThreshold =
+        ProfileSummaryBuilder::getHotCountThreshold(PS->getDetailedSummary());
+    OS << "# Hot count threshold: " << HotCountThreshold << "\n";
+    for (auto [NameRef, MaxCount] : NameRefAndMaxCount)
+      if (MaxCount >= HotCountThreshold)
+        OS << Reader->getSymtab().getFuncOrVarName(NameRef) << "\n";
----------------
mingmingl-llvm wrote:

nit: exit the loop after seeing the first counter that's smaller than `HotCountThreshold`, given NameRefAndMaxCount is sorted by count descendingly.

https://github.com/llvm/llvm-project/pull/149428