diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
--- a/clang/include/clang/Basic/CodeGenOptions.def
+++ b/clang/include/clang/Basic/CodeGenOptions.def
@@ -211,6 +211,8 @@
                                    ///< enable code coverage analysis.
 CODEGENOPT(DumpCoverageMapping , 1, 0) ///< Dump the generated coverage mapping
                                        ///< regions.
+CODEGENOPT(NoUnusedCoverage , 1, 0) ///< Turn off coverage mapping for code that
+                                    ///< is not emitted.

   /// If -fpcc-struct-return or -freg-struct-return is specified.
 ENUM_CODEGENOPT(StructReturnConvention, StructReturnConventionKind, 2, SRCK_Default)
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -5158,6 +5158,9 @@
 def dump_coverage_mapping : Flag<["-"], "dump-coverage-mapping">,
   HelpText<"Dump the coverage mapping records, for testing">,
   MarshallingInfoFlag<CodeGenOpts<"DumpCoverageMapping">>;
+def no_unused_coverage : Flag<["-"], "no-unused-coverage">,
+  HelpText<"Turn off coverage mapping for code that is not emitted">,
+  MarshallingInfoFlag<CodeGenOpts<"NoUnusedCoverage">>;
 def fuse_register_sized_bitfield_access: Flag<["-"], "fuse-register-sized-bitfield-access">,
   HelpText<"Use register sized accesses to bit-fields, when possible.">,
   MarshallingInfoFlag<CodeGenOpts<"UseRegisterSizedBitfieldAccess">>;
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -538,7 +538,9 @@
   EmitCtorList(GlobalDtors, "llvm.global_dtors");
   EmitGlobalAnnotations();
   EmitStaticExternCAliases();
-  EmitDeferredUnusedCoverageMappings();
+  if (!CodeGenOpts.NoUnusedCoverage) {
+    EmitDeferredUnusedCoverageMappings();
+  }
   CodeGenPGO(*this).setValueProfilingFlag(getModule());
   if (CoverageMapping)
     CoverageMapping->emit();