[llvm-exegesis] Analysis: Show value extents.

Summary: Screenshot attached in phabricator.

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D47318

llvm-svn: 333181
diff --git a/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h b/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
index 3a7d241..4362df8 100644
--- a/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
+++ b/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
@@ -18,6 +18,7 @@
 
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/YAMLTraits.h"
+#include <limits>
 #include <string>
 #include <vector>
 
@@ -61,6 +62,29 @@
   void writeYamlOrDie(const llvm::StringRef Filename);
 };
 
+//------------------------------------------------------------------------------
+// Utilities to work with Benchmark measures.
+
+// A class that measures stats over benchmark measures.
+class BenchmarkMeasureStats {
+public:
+  void push(const BenchmarkMeasure &BM);
+
+  double avg() const {
+    assert(NumValues);
+    return SumValues / NumValues;
+  }
+  double min() const { return MinValue; }
+  double max() const { return MaxValue; }
+
+private:
+  std::string Key;
+  double SumValues = 0.0;
+  int NumValues = 0;
+  double MaxValue = std::numeric_limits<double>::min();
+  double MinValue = std::numeric_limits<double>::max();
+};
+
 } // namespace exegesis
 
 #endif // LLVM_TOOLS_LLVM_EXEGESIS_BENCHMARKRESULT_H