diff --git a/lib/CodeGen/CodeGenPGO.cpp b/lib/CodeGen/CodeGenPGO.cpp
index d341baf523c57605271d14b06157810cde18ce22..2f1f211b72cfee6e205f971ca3dee10d715c4e68 100644
--- a/lib/CodeGen/CodeGenPGO.cpp
+++ b/lib/CodeGen/CodeGenPGO.cpp
@@ -908,8 +908,7 @@ void CodeGenPGO::emitCounterRegionMapping(const Decl *D) {
   llvm::raw_string_ostream OS(CoverageMapping);
   CoverageMappingGen MappingGen(*CGM.getCoverageMapping(),
                                 CGM.getContext().getSourceManager(),
-                                CGM.getLangOpts(), RegionCounterMap.get(),
-                                NumRegionCounters);
+                                CGM.getLangOpts(), RegionCounterMap.get());
   MappingGen.emitCounterMapping(D, OS);
   OS.flush();
 }
diff --git a/lib/CodeGen/CoverageMappingGen.cpp b/lib/CodeGen/CoverageMappingGen.cpp
index 2bfe0fb8600905eb38b635dbf156ed3271eee3e5..9900ebc014e8de48d763e69d9f34bc78d650641c 100644
--- a/lib/CodeGen/CoverageMappingGen.cpp
+++ b/lib/CodeGen/CoverageMappingGen.cpp
@@ -581,11 +581,9 @@ struct CounterCoverageMappingBuilder
 
   CounterCoverageMappingBuilder(
       CoverageMappingModuleGen &CVM,
-      llvm::DenseMap<const Stmt *, unsigned> &CounterMap,
-      unsigned NumRegionCounters, SourceManager &SM,
+      llvm::DenseMap<const Stmt *, unsigned> &CounterMap, SourceManager &SM,
       const LangOptions &LangOpts)
-      : CoverageMappingBuilder(CVM, SM, LangOpts), CounterMap(CounterMap),
-        Builder(NumRegionCounters) {}
+      : CoverageMappingBuilder(CVM, SM, LangOpts), CounterMap(CounterMap) {}
 
   /// \brief Write the mapping data to the output stream
   void write(llvm::raw_ostream &OS) {
@@ -1213,8 +1211,7 @@ unsigned CoverageMappingModuleGen::getFileID(const FileEntry *File) {
 void CoverageMappingGen::emitCounterMapping(const Decl *D,
                                             llvm::raw_ostream &OS) {
   assert(CounterMap);
-  CounterCoverageMappingBuilder Walker(CVM, *CounterMap, NumRegionCounters, SM,
-                                       LangOpts);
+  CounterCoverageMappingBuilder Walker(CVM, *CounterMap, SM, LangOpts);
   Walker.VisitDecl(D);
   Walker.write(OS);
 }
diff --git a/lib/CodeGen/CoverageMappingGen.h b/lib/CodeGen/CoverageMappingGen.h
index 45e0db8bce3cac07f605bb5afd4b980d513a641b..e4c6412be09cf3116446ada4bde7215947881ddf 100644
--- a/lib/CodeGen/CoverageMappingGen.h
+++ b/lib/CodeGen/CoverageMappingGen.h
@@ -87,20 +87,16 @@ class CoverageMappingGen {
   SourceManager &SM;
   const LangOptions &LangOpts;
   llvm::DenseMap<const Stmt *, unsigned> *CounterMap;
-  unsigned NumRegionCounters;
 
 public:
   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
                      const LangOptions &LangOpts)
-      : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(nullptr),
-        NumRegionCounters(0) {}
+      : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(nullptr) {}
 
   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
                      const LangOptions &LangOpts,
-                     llvm::DenseMap<const Stmt *, unsigned> *CounterMap,
-                     unsigned NumRegionCounters)
-      : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(CounterMap),
-        NumRegionCounters(NumRegionCounters) {}
+                     llvm::DenseMap<const Stmt *, unsigned> *CounterMap)
+      : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(CounterMap) {}
 
   /// \brief Emit the coverage mapping data which maps the regions of
   /// code to counters that will be used to find the execution