diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 7908b8f..3c0c3c5 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -140,9 +140,9 @@
   HelpText<"Emit a gcov coverage notes file when compiling.">;
 def femit_coverage_data: Flag<"-femit-coverage-data">,
   HelpText<"Instrument the program to emit gcov coverage data when run.">;
-def coverage_dir : Separate<"-coverage-dir">,
-  HelpText<"Emit coverage data to this directory.">;
-def coverage_dir_EQ : Joined<"-coverage-dir=">, Alias<coverage_dir>;
+def coverage_file : Separate<"-coverage-file">,
+  HelpText<"Emit coverage data to this filename. The extension will be replaced.">;
+def coverage_file_EQ : Joined<"-coverage-file=">, Alias<coverage_file>;
 def relaxed_aliasing : Flag<"-relaxed-aliasing">,
   HelpText<"Turn off Type Based Alias Analysis">;
 def masm_verbose : Flag<"-masm-verbose">,
diff --git a/include/clang/Frontend/CodeGenOptions.h b/include/clang/Frontend/CodeGenOptions.h
index 7221f0d..1c686c7 100644
--- a/include/clang/Frontend/CodeGenOptions.h
+++ b/include/clang/Frontend/CodeGenOptions.h
@@ -95,8 +95,9 @@
   /// The code model to use (-mcmodel).
   std::string CodeModel;
 
-  /// The directory in which to place coverage data files.
-  std::string CoverageDir;
+  /// The filename with path we use for coverage files. The extension will be
+  /// replaced.
+  std::string CoverageFile;
 
   /// Enable additional debugging information.
   std::string DebugPass;
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 22df86a..4ce12ec 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -134,7 +134,7 @@
     EmitDeclMetadata();
 
   if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes)
-    EmitCoverageDir();
+    EmitCoverageFile();
 }
 
 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
@@ -2219,16 +2219,16 @@
   }
 }
 
-void CodeGenModule::EmitCoverageDir() {
-  if (!getCodeGenOpts().CoverageDir.empty()) {
+void CodeGenModule::EmitCoverageFile() {
+  if (!getCodeGenOpts().CoverageFile.empty()) {
     if (llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu")) {
       llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov");
       llvm::LLVMContext &Ctx = TheModule.getContext();
-      llvm::MDString *CoverageDir =
-          llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDir);
+      llvm::MDString *CoverageFile =
+          llvm::MDString::get(Ctx, getCodeGenOpts().CoverageFile);
       for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) {
         llvm::MDNode *CU = CUNode->getOperand(i);
-        llvm::Value *node[] = { CoverageDir, CU };
+        llvm::Value *node[] = { CoverageFile, CU };
         llvm::MDNode *N = llvm::MDNode::get(Ctx, node);
         GCov->addOperand(N);
       }
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index 65ee922..ce708c8 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -735,9 +735,9 @@
 
   void EmitDeclMetadata();
 
-  /// EmitCoverageDir - Emit the llvm.gcov metadata used to tell LLVM where
+  /// EmitCoverageFile - Emit the llvm.gcov metadata used to tell LLVM where
   /// to emit the .gcno and .gcda files in a way that persists in .bc files.
-  void EmitCoverageDir();
+  void EmitCoverageFile();
 
   /// MayDeferGeneration - Determine if the given decl can be emitted
   /// lazily; this is only relevant for definitions. The given decl
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index f4e0f2e..239edb5 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1306,12 +1306,8 @@
   if (C.getArgs().hasArg(options::OPT_c) ||
       C.getArgs().hasArg(options::OPT_S)) {
     if (Output.isFilename()) {
-      llvm::StringRef CoverageDir =
-          llvm::sys::path::parent_path(Output.getFilename());
-      if (!CoverageDir.empty()) {
-        CmdArgs.push_back("-coverage-dir");
-        CmdArgs.push_back(Args.MakeArgString(CoverageDir));
-      }
+      CmdArgs.push_back("-coverage-file");
+      CmdArgs.push_back(Args.MakeArgString(Output.getFilename()));
     }
   }
 
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 180ce3e..924e5ed 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -974,7 +974,7 @@
   Opts.InstrumentForProfiling = Args.hasArg(OPT_pg);
   Opts.EmitGcovArcs = Args.hasArg(OPT_femit_coverage_data);
   Opts.EmitGcovNotes = Args.hasArg(OPT_femit_coverage_notes);
-  Opts.CoverageDir = Args.getLastArgValue(OPT_coverage_dir);
+  Opts.CoverageFile = Args.getLastArgValue(OPT_coverage_file);
 
   if (Arg *A = Args.getLastArg(OPT_fobjc_dispatch_method_EQ)) {
     llvm::StringRef Name = A->getValue(Args);