Index: cfe/trunk/lib/Driver/ToolChains/Darwin.cpp
===================================================================
--- cfe/trunk/lib/Driver/ToolChains/Darwin.cpp
+++ cfe/trunk/lib/Driver/ToolChains/Darwin.cpp
@@ -514,6 +514,14 @@
     }
   }
 
+  // Setup statistics file output.
+  SmallString<128> StatsFile =
+      getStatsFileName(Args, Output, Inputs[0], getToolChain().getDriver());
+  if (!StatsFile.empty()) {
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back(Args.MakeArgString("-lto-stats-file=" + StatsFile.str()));
+  }
+
   // It seems that the 'e' option is completely ignored for dynamic executables
   // (the default), and with static executables, the last one wins, as expected.
   Args.AddAllArgs(CmdArgs, {options::OPT_d_Flag, options::OPT_s, options::OPT_t,
Index: llvm/trunk/include/llvm/LTO/LTO.h
===================================================================
--- llvm/trunk/include/llvm/LTO/LTO.h
+++ llvm/trunk/include/llvm/LTO/LTO.h
@@ -87,6 +87,10 @@
                          StringRef LTORemarksPasses,
                          bool LTOPassRemarksWithHotness, int Count = -1);
 
+/// Setups the output file for saving statistics.
+Expected<std::unique_ptr<ToolOutputFile>>
+setupStatsFile(StringRef StatsFilename);
+
 class LTO;
 struct SymbolResolution;
 class ThinBackendProc;
Index: llvm/trunk/include/llvm/LTO/legacy/LTOCodeGenerator.h
===================================================================
--- llvm/trunk/include/llvm/LTO/legacy/LTOCodeGenerator.h
+++ llvm/trunk/include/llvm/LTO/legacy/LTOCodeGenerator.h
@@ -241,6 +241,7 @@
   TargetMachine::CodeGenFileType FileType = TargetMachine::CGFT_ObjectFile;
   std::unique_ptr<ToolOutputFile> DiagnosticOutputFile;
   bool Freestanding = false;
+  std::unique_ptr<ToolOutputFile> StatsFile = nullptr;
 };
 }
 #endif
Index: llvm/trunk/lib/LTO/LTO.cpp
===================================================================
--- llvm/trunk/lib/LTO/LTO.cpp
+++ llvm/trunk/lib/LTO/LTO.cpp
@@ -885,16 +885,10 @@
                                   isPrevailing, Conf.OptLevel > 0);
 
   // Setup output file to emit statistics.
-  std::unique_ptr<ToolOutputFile> StatsFile = nullptr;
-  if (!Conf.StatsFile.empty()) {
-    EnableStatistics(false);
-    std::error_code EC;
-    StatsFile =
-        llvm::make_unique<ToolOutputFile>(Conf.StatsFile, EC, sys::fs::F_None);
-    if (EC)
-      return errorCodeToError(EC);
-    StatsFile->keep();
-  }
+  auto StatsFileOrErr = setupStatsFile(Conf.StatsFile);
+  if (!StatsFileOrErr)
+    return StatsFileOrErr.takeError();
+  std::unique_ptr<ToolOutputFile> StatsFile = std::move(StatsFileOrErr.get());
 
   // Finalize linking of regular LTO modules containing summaries now that
   // we have computed liveness information.
@@ -1343,3 +1337,20 @@
   DiagnosticFile->keep();
   return std::move(DiagnosticFile);
 }
+
+Expected<std::unique_ptr<ToolOutputFile>>
+lto::setupStatsFile(StringRef StatsFilename) {
+  // Setup output file to emit statistics.
+  if (StatsFilename.empty())
+    return nullptr;
+
+  llvm::EnableStatistics(false);
+  std::error_code EC;
+  auto StatsFile =
+      llvm::make_unique<ToolOutputFile>(StatsFilename, EC, sys::fs::F_None);
+  if (EC)
+    return errorCodeToError(EC);
+
+  StatsFile->keep();
+  return std::move(StatsFile);
+}
Index: llvm/trunk/lib/LTO/LTOCodeGenerator.cpp
===================================================================
--- llvm/trunk/lib/LTO/LTOCodeGenerator.cpp
+++ llvm/trunk/lib/LTO/LTOCodeGenerator.cpp
@@ -95,6 +95,11 @@
     "lto-pass-remarks-with-hotness",
     cl::desc("With PGO, include profile count in optimization remarks"),
     cl::Hidden);
+
+cl::opt<std::string> LTOStatsFile(
+    "lto-stats-file",
+    cl::desc("Save statistics to the specified file"),
+    cl::Hidden);
 }
 
 LTOCodeGenerator::LTOCodeGenerator(LLVMContext &Context)
@@ -518,6 +523,14 @@
   }
   DiagnosticOutputFile = std::move(*DiagFileOrErr);
 
+  // Setup output file to emit statistics.
+  auto StatsFileOrErr = lto::setupStatsFile(LTOStatsFile);
+  if (!StatsFileOrErr) {
+    errs() << "Error: " << toString(StatsFileOrErr.takeError()) << "\n";
+    report_fatal_error("Can't get an output file for the statistics");
+  }
+  StatsFile = std::move(StatsFileOrErr.get());
+
   // We always run the verifier once on the merged module, the `DisableVerify`
   // parameter only applies to subsequent verify.
   verifyMergedModuleOnce();
@@ -584,9 +597,13 @@
                               [&]() { return createTargetMachine(); }, FileType,
                               ShouldRestoreGlobalsLinkage);
 
-  // If statistics were requested, print them out after codegen.
-  if (llvm::AreStatisticsEnabled())
-    llvm::PrintStatistics();
+  // If statistics were requested, save them to the specified file or
+  // print them out after codegen.
+  if (StatsFile)
+    PrintStatisticsJSON(StatsFile->os());
+  else if (AreStatisticsEnabled())
+    PrintStatistics();
+
   reportAndResetTimings();
 
   finishOptimizationRemarks();