[PATCH] D100068: [llvm-dwarfdump] Fix slowdown in dwarfdump statistics.

[Rumeet Dhindsa via Phabricator via llvm-commits]

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Fixed slowdown that happened after https://reviews.llvm.org/D96045,

While running dwarfdump --statistics, it spends more than 50% of the time in collectZeroCovInlinedVars function.

In function collectStatsForObjectFile, variable InlinedFnsToBeProcessed is being created outside the for loop. The inline functions to be processed are appended and processed multiple times. Hence, moving the creation of that variable into the for loop which fixes the slowdown.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D100068

Files:
  llvm/tools/llvm-dwarfdump/Statistics.cpp


Index: llvm/tools/llvm-dwarfdump/Statistics.cpp
===================================================================
--- llvm/tools/llvm-dwarfdump/Statistics.cpp
+++ llvm/tools/llvm-dwarfdump/Statistics.cpp
@@ -715,10 +715,10 @@
   GlobalStats GlobalStats;
   LocationStats LocStats;
   InlinedVarsTyMap GlobalInlinedFnInfo;
-  InlinedFnInstacesTy InlinedFnsToBeProcessed;
   StringMap<PerFunctionStats> Statistics;
   for (const auto &CU : static_cast<DWARFContext *>(&DICtx)->compile_units()) {
     if (DWARFDie CUDie = CU->getNonSkeletonUnitDIE(false)) {
+      InlinedFnInstacesTy InlinedFnsToBeProcessed;
       collectStatsRecursive(CUDie, "/", "g", 0, 0, Statistics, GlobalStats,
                             LocStats, GlobalInlinedFnInfo,
                             InlinedFnsToBeProcessed);


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