Index: test/tools/llvm-exegesis/X86/latency-by-opcode-name.s
===================================================================
--- test/tools/llvm-exegesis/X86/latency-by-opcode-name.s
+++ test/tools/llvm-exegesis/X86/latency-by-opcode-name.s
@@ -1,6 +1,8 @@
 # RUN: llvm-exegesis -mode=latency -opcode-name=ADD32rr | FileCheck %s
 
-CHECK:      mode:            latency
+CHECK:      ---
+CHECK-NEXT: mode:            latency
 CHECK-NEXT: key:
 CHECK-NEXT:   instructions:
 CHECK-NEXT:     ADD32rr
+CHECK-LAST: ...
Index: tools/llvm-exegesis/lib/BenchmarkResult.cpp
===================================================================
--- tools/llvm-exegesis/lib/BenchmarkResult.cpp
+++ tools/llvm-exegesis/lib/BenchmarkResult.cpp
@@ -269,7 +269,9 @@
                                        llvm::raw_ostream &OS) {
   llvm::yaml::Output Yout(OS);
   YamlContext Context(State);
+  Yout.beginDocuments();
   llvm::yaml::yamlize(Yout, *this, /*unused*/ true, Context);
+  Yout.endDocuments();
 }
 
 void InstructionBenchmark::readYamlFrom(const LLVMState &State,