Index: ELF/Config.h
===================================================================
--- ELF/Config.h
+++ ELF/Config.h
@@ -92,6 +92,7 @@
   llvm::StringRef Fini;
   llvm::StringRef Init;
   llvm::StringRef LTOAAPipeline;
+  llvm::StringRef LTOCSProfileFile;
   llvm::StringRef LTONewPmPasses;
   llvm::StringRef LTOObjPath;
   llvm::StringRef LTOSampleProfile;
@@ -150,6 +151,7 @@
   bool HasDynSymTab;
   bool IgnoreDataAddressEquality;
   bool IgnoreFunctionAddressEquality;
+  bool LTOCSPGOGen = false;
   bool LTODebugPassManager;
   bool LTONewPassManager;
   bool MergeArmExidx;
Index: ELF/Driver.cpp
===================================================================
--- ELF/Driver.cpp
+++ ELF/Driver.cpp
@@ -798,6 +798,8 @@
       Args.hasArg(OPT_ignore_function_address_equality);
   Config->Init = Args.getLastArgValue(OPT_init, "_init");
   Config->LTOAAPipeline = Args.getLastArgValue(OPT_lto_aa_pipeline);
+  Config->LTOCSProfileFile = Args.getLastArgValue(OPT_lto_cs_profile_file);
+  Config->LTOCSPGOGen = Args.hasArg(OPT_lto_cs_pgo_gen);
   Config->LTODebugPassManager = Args.hasArg(OPT_lto_debug_pass_manager);
   Config->LTONewPassManager = Args.hasArg(OPT_lto_new_pass_manager);
   Config->LTONewPmPasses = Args.getLastArgValue(OPT_lto_newpm_passes);
Index: ELF/LTO.cpp
===================================================================
--- ELF/LTO.cpp
+++ ELF/LTO.cpp
@@ -103,6 +103,9 @@
   C.DebugPassManager = Config->LTODebugPassManager;
   C.DwoDir = Config->DwoDir;
 
+  C.CSIRProfile = Config->LTOCSProfileFile;
+  C.RunCSIRInstr = Config->LTOCSPGOGen;
+
   if (Config->EmitLLVM) {
     C.PostInternalizeModuleHook = [](size_t Task, const Module &M) {
       if (std::unique_ptr<raw_fd_ostream> OS = openFile(Config->OutputFile))
Index: ELF/Options.td
===================================================================
--- ELF/Options.td
+++ ELF/Options.td
@@ -437,6 +437,10 @@
   HelpText<"Optimization level for LTO">;
 def lto_partitions: J<"lto-partitions=">,
   HelpText<"Number of LTO codegen partitions">;
+def lto_cs_pgo_gen: F<"lto-cs-pgo-gen">,
+  HelpText<"Perform context senstive PGO instrumentation">;
+def lto_cs_profile_file: J<"lto-cs-profile-file=">,
+  HelpText<"Context sensitive profile file path">;
 def lto_sample_profile: J<"lto-sample-profile=">,
   HelpText<"Sample profile file path">;
 def disable_verify: F<"disable-verify">;
@@ -465,6 +469,10 @@
 def: F<"plugin-opt=new-pass-manager">,
   Alias<lto_new_pass_manager>, HelpText<"Alias for -lto-new-pass-manager">;
 def plugin_opt_obj_path_eq: J<"plugin-opt=obj-path=">;
+def: F<"plugin-opt=cs-profile-generate">,
+  Alias<lto_cs_pgo_gen>, HelpText<"Alias for -lto-cs-pgo-gen">;
+def: J<"plugin-opt=cs-profile-path=">,
+  Alias<lto_cs_profile_file>, HelpText<"Alias for -lto-cs-profile-file">;
 def: J<"plugin-opt=sample-profile=">,
   Alias<lto_sample_profile>, HelpText<"Alias for -lto-sample-profile">;
 def: F<"plugin-opt=save-temps">, Alias<save_temps>, HelpText<"Alias for -save-temps">;