Index: tools/llvm-exegesis/lib/Clustering.h
===================================================================
--- tools/llvm-exegesis/lib/Clustering.h
+++ tools/llvm-exegesis/lib/Clustering.h
@@ -89,8 +89,15 @@
   const std::vector<Cluster> &getValidClusters() const { return Clusters_; }
 
   // Returns true if the given point is within a distance Epsilon of each other.
-  bool isNeighbour(const std::vector<BenchmarkMeasure> &P,
-                   const std::vector<BenchmarkMeasure> &Q) const;
+  inline bool isNeighbour(const std::vector<BenchmarkMeasure> &P,
+                          const std::vector<BenchmarkMeasure> &Q) const {
+    double DistanceSquared = 0.0;
+    for (size_t I = 0, E = P.size(); I < E; ++I) {
+      const auto Diff = P[I].PerInstructionValue - Q[I].PerInstructionValue;
+      DistanceSquared += Diff * Diff;
+    }
+    return DistanceSquared <= EpsilonSquared_;
+  }
 
 private:
   InstructionBenchmarkClustering(
Index: tools/llvm-exegesis/lib/Clustering.cpp
===================================================================
--- tools/llvm-exegesis/lib/Clustering.cpp
+++ tools/llvm-exegesis/lib/Clustering.cpp
@@ -49,17 +49,6 @@
   }
 }
 
-bool InstructionBenchmarkClustering::isNeighbour(
-    const std::vector<BenchmarkMeasure> &P,
-    const std::vector<BenchmarkMeasure> &Q) const {
-  double DistanceSquared = 0.0;
-  for (size_t I = 0, E = P.size(); I < E; ++I) {
-    const auto Diff = P[I].PerInstructionValue - Q[I].PerInstructionValue;
-    DistanceSquared += Diff * Diff;
-  }
-  return DistanceSquared <= EpsilonSquared_;
-}
-
 InstructionBenchmarkClustering::InstructionBenchmarkClustering(
     const std::vector<InstructionBenchmark> &Points,
     const double EpsilonSquared)