diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 1240132..e03bc11 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -365,6 +365,10 @@
   Flags<[DriverOption, CC1Option]>,
   HelpText<"Disable generation of linker directives for automatic library linking">;
 
+def fprofile_sample_use_EQ : Joined<["-"], "fprofile-sample-use=">,
+    Group<f_Group>, Flags<[DriverOption, CC1Option]>,
+    HelpText<"Enable sample-based profile guided optimizations">;
+
 def fblocks : Flag<["-"], "fblocks">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Enable the 'blocks' language feature">;
 def fbootclasspath_EQ : Joined<["-"], "fbootclasspath=">, Group<f_Group>;
diff --git a/include/clang/Frontend/CodeGenOptions.h b/include/clang/Frontend/CodeGenOptions.h
index 45d2bda..86aabf7 100644
--- a/include/clang/Frontend/CodeGenOptions.h
+++ b/include/clang/Frontend/CodeGenOptions.h
@@ -131,6 +131,9 @@
   /// A list of dependent libraries.
   std::vector<std::string> DependentLibraries;
 
+  /// Name of the profile file to use with -fprofile-sample-use.
+  std::string SampleProfileFile;
+
 public:
   // Define accessors/mutators for code generation options of enumeration type.
 #define CODEGENOPT(Name, Bits, Default)
diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 7a62e4e..e159a7a 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -154,6 +154,14 @@
     PM.add(createObjCARCOptPass());
 }
 
+static void addSampleProfileLoaderPass(const PassManagerBuilder &Builder,
+                                       PassManagerBase &PM) {
+  const PassManagerBuilderWrapper &BuilderWrapper =
+      static_cast<const PassManagerBuilderWrapper &>(Builder);
+  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
+  PM.add(createSampleProfileLoaderPass(CGOpts.SampleProfileFile));
+}
+
 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
                                     PassManagerBase &PM) {
   PM.add(createBoundsCheckingPass());
@@ -235,6 +243,10 @@
   PMBuilder.DisableUnitAtATime = !CodeGenOpts.UnitAtATime;
   PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
 
+  if (!CodeGenOpts.SampleProfileFile.empty())
+    PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
+                           addSampleProfileLoaderPass);
+
   // In ObjC ARC mode, add the main ARC optimization passes.
   if (LangOpts.ObjCAutoRefCount) {
     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 810e3c1..a4e4672 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -3074,6 +3074,13 @@
 
   // Forward -f options with positive and negative forms; we translate
   // these by hand.
+  if (Arg *A = Args.getLastArg(options::OPT_fprofile_sample_use_EQ)) {
+    StringRef fname = A->getValue();
+    if (!llvm::sys::fs::exists(fname))
+      D.Diag(diag::err_drv_no_such_file) << fname;
+    else
+      A->render(Args, CmdArgs);
+  }
 
   if (Args.hasArg(options::OPT_mkernel)) {
     if (!Args.hasArg(options::OPT_fapple_kext) && types::isCXX(InputType))
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 8bac00b..009d6ec 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -357,6 +357,7 @@
                    (Opts.OptimizationLevel > 1 && !Opts.OptimizeSize));
 
   Opts.Autolink = !Args.hasArg(OPT_fno_autolink);
+  Opts.SampleProfileFile = Args.getLastArgValue(OPT_fprofile_sample_use_EQ);
   Opts.AsmVerbose = Args.hasArg(OPT_masm_verbose);
   Opts.ObjCAutoRefCountExceptions = Args.hasArg(OPT_fobjc_arc_exceptions);
   Opts.CUDAIsDevice = Args.hasArg(OPT_fcuda_is_device);
diff --git a/test/Driver/Inputs/file.prof b/test/Driver/Inputs/file.prof
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/test/Driver/Inputs/file.prof
diff --git a/test/Driver/clang_f_opts.c b/test/Driver/clang_f_opts.c
index e837583..a443bba 100644
--- a/test/Driver/clang_f_opts.c
+++ b/test/Driver/clang_f_opts.c
@@ -44,6 +44,9 @@
 // CHECK-UNROLL-LOOPS: "-funroll-loops"
 // CHECK-NO-UNROLL-LOOPS: "-fno-unroll-loops"
 
+// RUN: %clang -### -S -fprofile-sample-use=%S/Inputs/file.prof %s 2>&1 | FileCheck -check-prefix=CHECK-SAMPLE-PROFILE %s
+// CHECK-SAMPLE-PROFILE: "-fprofile-sample-use={{.*}}/file.prof"
+
 // RUN: %clang -### -S -fvectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-vectorize -fvectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-VECTORIZE %s