Index: include/clang/Driver/Options.td
===================================================================
--- include/clang/Driver/Options.td
+++ include/clang/Driver/Options.td
@@ -769,6 +769,9 @@
 def fprofile_exclude_files_EQ : Joined<["-"], "fprofile-exclude-files=">,
     Group<f_Group>, Flags<[CC1Option, CoreOption]>,
     HelpText<"Instrument only functions from files where names don't match all the regexes separated by a semi-colon">;
+def forder_file_instrumentation : Flag<["-"], "forder-file-instrumentation">,
+    Group<f_Group>, Flags<[CoreOption]>,
+    HelpText<"Generate instrumented code to collect order file into default.profraw file (overridden by '=' form of option or LLVM_PROFILE_FILE env var)">;
 
 def faddrsig : Flag<["-"], "faddrsig">, Group<f_Group>, Flags<[CoreOption, CC1Option]>,
   HelpText<"Emit an address-significance table">;
Index: lib/Driver/ToolChain.cpp
===================================================================
--- lib/Driver/ToolChain.cpp
+++ lib/Driver/ToolChain.cpp
@@ -407,7 +407,8 @@
       Args.hasArg(options::OPT_fprofile_generate_EQ) ||
       Args.hasArg(options::OPT_fprofile_instr_generate) ||
       Args.hasArg(options::OPT_fprofile_instr_generate_EQ) ||
-      Args.hasArg(options::OPT_fcreate_profile))
+      Args.hasArg(options::OPT_fcreate_profile) ||
+      Args.hasArg(options::OPT_forder_file_instrumentation)) 
     return true;
 
   return false;
Index: lib/Driver/ToolChains/Clang.cpp
===================================================================
--- lib/Driver/ToolChains/Clang.cpp
+++ lib/Driver/ToolChains/Clang.cpp
@@ -5307,6 +5307,17 @@
     }
   }
 
+  if (Args.hasArg(options::OPT_forder_file_instrumentation)) {
+     CmdArgs.push_back("-forder-file-instrumentation");
+     // Enable order file instrumentation when ThinLTO is not on. When ThinLTO is
+     // on, we need to pass these flags as linker flags and that will be handled
+     // outside of the compiler.
+     if (D.getLTOMode() != LTOK_Thin) {
+       CmdArgs.push_back("-mllvm");
+       CmdArgs.push_back("-enable-order-file-instrumentation");
+     }
+  }
+
   if (Arg *A = Args.getLastArg(options::OPT_fforce_enable_int128,
                                options::OPT_fno_force_enable_int128)) {
     if (A->getOption().matches(options::OPT_fforce_enable_int128))
Index: test/Driver/clang_f_opts.c
===================================================================
--- test/Driver/clang_f_opts.c
+++ test/Driver/clang_f_opts.c
@@ -121,6 +121,7 @@
 // RUN: %clang -### -S -fcoverage-mapping -fno-coverage-mapping %s 2>&1 | FileCheck -check-prefix=CHECK-DISABLE-COVERAGE %s
 // RUN: %clang -### -S -fprofile-instr-generate -fcoverage-mapping -fno-coverage-mapping %s 2>&1 | FileCheck -check-prefix=CHECK-DISABLE-COVERAGE %s
 // RUN: %clang -### -S -fprofile-remapping-file foo/bar.txt %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-REMAP %s
+// RUN: %clang -### -S -forder-file-instrumentation %s 2>&1 | FileCheck -check-prefix=CHECK-ORDERFILE-INSTR %s
 // CHECK-PROFILE-GENERATE: "-fprofile-instrument=clang"
 // CHECK-PROFILE-GENERATE-LLVM: "-fprofile-instrument=llvm"
 // CHECK-PROFILE-GENERATE-DIR: "-fprofile-instrument-path=/some/dir{{/|\\\\}}{{.*}}"
@@ -132,6 +133,8 @@
 // CHECK-COVERAGE-AND-GEN: '-fcoverage-mapping' only allowed with '-fprofile-instr-generate'
 // CHECK-DISABLE-COVERAGE-NOT: "-fcoverage-mapping"
 // CHECK-PROFILE-REMAP: "-fprofile-remapping-file=foo/bar.txt"
+// CHECK-ORDERFILE-INSTR: "-forder-file-instrumentation"
+// CHECK-ORDERFILE-INSTR: "-enable-order-file-instrumentation"
 
 // RUN: %clang -### -S -fprofile-use %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-USE %s
 // RUN: %clang -### -S -fprofile-instr-use %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-USE %s