Index: Common/TargetOptionsCommandFlags.cpp
===================================================================
--- Common/TargetOptionsCommandFlags.cpp
+++ Common/TargetOptionsCommandFlags.cpp
@@ -30,3 +30,7 @@
 llvm::Optional<llvm::CodeModel::Model> lld::GetCodeModelFromCMModel() {
   return getCodeModel();
 }
+
+std::string lld::GetCPUStr() {
+  return ::getCPUStr();
+}
Index: ELF/LTO.cpp
===================================================================
--- ELF/LTO.cpp
+++ ELF/LTO.cpp
@@ -87,6 +87,7 @@
   Conf.DisableVerify = Config->DisableVerify;
   Conf.DiagHandler = diagnosticHandler;
   Conf.OptLevel = Config->LTOO;
+  Conf.CPU = GetCPUStr();
 
   // Set up a custom pipeline if we've been asked to.
   Conf.OptPipeline = Config->LTONewPmPasses;
Index: include/lld/Common/TargetOptionsCommandFlags.h
===================================================================
--- include/lld/Common/TargetOptionsCommandFlags.h
+++ include/lld/Common/TargetOptionsCommandFlags.h
@@ -18,4 +18,5 @@
 namespace lld {
 llvm::TargetOptions InitTargetOptionsFromCodeGenFlags();
 llvm::Optional<llvm::CodeModel::Model> GetCodeModelFromCMModel();
+std::string GetCPUStr();
 }