[llvm-exegesis][NFC] Use an enum instead of a string for benchmark mode.

Summary: YAML encoding is backwards-compatible.

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D47705

llvm-svn: 333886

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h b/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
index 41d631eca4b..b160507afc6 100644
--- a/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
+++ b/llvm/tools/llvm-exegesis/lib/BenchmarkResult.h
@@ -27,8 +27,8 @@ namespace exegesis {
 struct InstructionBenchmarkKey {
   // The LLVM opcode name.
   std::string OpcodeName;
-  // The benchmark mode.
-  std::string Mode;
+  enum ModeE { Unknown, Latency, Uops };
+  ModeE Mode;
   // An opaque configuration, that can be used to separate several benchmarks of
   // the same instruction under different configurations.
   std::string Config;