1 files changed, 24 insertions, 5 deletions
diff --git a/llvm/lib/Transforms/IPO/SampleProfile.cpp b/llvm/lib/Transforms/IPO/SampleProfile.cpp
index df8c8a0f7c4..816fc9336d0 100644
--- a/llvm/lib/Transforms/IPO/SampleProfile.cpp
+++ b/llvm/lib/Transforms/IPO/SampleProfile.cpp
@@ -225,20 +225,39 @@ bool SampleCoverageTracker::markSamplesUsed(const FunctionSamples *Samples,
 unsigned
 SampleCoverageTracker::countUsedSamples(const FunctionSamples *Samples) const {
   auto I = SampleCoverage.find(Samples);
+
+  // The size of the coverage map for Samples represents the number of records
+  // that were marked used at least once.
   unsigned Count = (I != SampleCoverage.end()) ? I->second.size() : 0;
-  for (const auto &I : Samples->getCallsiteSamples())
-    Count += countUsedSamples(&I.second);
+
+  // If there are inlined callsites in this function, count the samples found
+  // in the respective bodies. However, do not bother counting callees with 0
+  // total samples, these are callees that were never invoked at runtime.
+  for (const auto &I : Samples->getCallsiteSamples()) {
+    const FunctionSamples *CalleeSamples = &I.second;
+    if (CalleeSamples->getTotalSamples() > 0)
+      Count += countUsedSamples(&I.second);
+  }
+
   return Count;
 }
 
 /// Return the number of sample records in the body of this profile.
 ///
-/// The count includes all the samples in inlined callees.
+/// The count includes all the samples in inlined callees. However, callsites
+/// with 0 samples indicate inlined function calls that were never actually
+/// invoked at runtime. Ignore these callsites for coverage purposes.
 unsigned
 SampleCoverageTracker::countBodySamples(const FunctionSamples *Samples) const {
   unsigned Count = Samples->getBodySamples().size();
-  for (const auto &I : Samples->getCallsiteSamples())
-    Count += countBodySamples(&I.second);
+
+  // Count all the callsites with non-zero samples.
+  for (const auto &I : Samples->getCallsiteSamples()) {
+    const FunctionSamples *CalleeSamples = &I.second;
+    if (CalleeSamples->getTotalSamples() > 0)
+      Count += countBodySamples(&I.second);
+  }
+
   return Count;
 }