diff --git a/llvm/lib/AsmParser/LLParser.h b/llvm/lib/AsmParser/LLParser.h
--- a/llvm/lib/AsmParser/LLParser.h
+++ b/llvm/lib/AsmParser/LLParser.h
@@ -262,8 +262,8 @@
     bool parseOptionalReturnAttrs(AttrBuilder &B);
     bool parseOptionalLinkage(unsigned &Res, bool &HasLinkage,
                               unsigned &Visibility, unsigned &DLLStorageClass,
-                              bool &DSOLocal);
-    void parseOptionalDSOLocal(bool &DSOLocal);
+                              bool &ExplicitDSOPreemption, bool &DSOLocal);
+    void parseOptionalDSOLocal(bool &ExplicitDSOPreemption, bool &DSOLocal);
     void parseOptionalVisibility(unsigned &Res);
     void parseOptionalDLLStorageClass(unsigned &Res);
     bool parseOptionalCallingConv(unsigned &CC);
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -623,11 +623,11 @@
 
   bool HasLinkage;
   unsigned Linkage, Visibility, DLLStorageClass;
-  bool DSOLocal;
+  bool ExplicitDSOPreemption, DSOLocal;
   GlobalVariable::ThreadLocalMode TLM;
   GlobalVariable::UnnamedAddr UnnamedAddr;
   if (parseOptionalLinkage(Linkage, HasLinkage, Visibility, DLLStorageClass,
-                           DSOLocal) ||
+                           ExplicitDSOPreemption, DSOLocal) ||
       parseOptionalThreadLocal(TLM) || parseOptionalUnnamedAddr(UnnamedAddr))
     return true;
 
@@ -652,12 +652,12 @@
 
   bool HasLinkage;
   unsigned Linkage, Visibility, DLLStorageClass;
-  bool DSOLocal;
+  bool ExplicitDSOPreemption, DSOLocal;
   GlobalVariable::ThreadLocalMode TLM;
   GlobalVariable::UnnamedAddr UnnamedAddr;
   if (parseToken(lltok::equal, "expected '=' in global variable") ||
       parseOptionalLinkage(Linkage, HasLinkage, Visibility, DLLStorageClass,
-                           DSOLocal) ||
+                           ExplicitDSOPreemption, DSOLocal) ||
       parseOptionalThreadLocal(TLM) || parseOptionalUnnamedAddr(UnnamedAddr))
     return true;
 
@@ -1972,11 +1972,13 @@
 ///   ::= 'external'
 bool LLParser::parseOptionalLinkage(unsigned &Res, bool &HasLinkage,
                                     unsigned &Visibility,
-                                    unsigned &DLLStorageClass, bool &DSOLocal) {
+                                    unsigned &DLLStorageClass,
+                                    bool &ExplicitDSOPreemption,
+                                    bool &DSOLocal) {
   Res = parseOptionalLinkageAux(Lex.getKind(), HasLinkage);
   if (HasLinkage)
     Lex.Lex();
-  parseOptionalDSOLocal(DSOLocal);
+  parseOptionalDSOLocal(ExplicitDSOPreemption, DSOLocal);
   parseOptionalVisibility(Visibility);
   parseOptionalDLLStorageClass(DLLStorageClass);
 
@@ -1987,16 +1989,20 @@
   return false;
 }
 
-void LLParser::parseOptionalDSOLocal(bool &DSOLocal) {
+void LLParser::parseOptionalDSOLocal(bool &ExplicitDSOPreemption,
+                                     bool &DSOLocal) {
   switch (Lex.getKind()) {
   default:
+    ExplicitDSOPreemption = false;
     DSOLocal = false;
     break;
   case lltok::kw_dso_local:
+    ExplicitDSOPreemption = true;
     DSOLocal = true;
     Lex.Lex();
     break;
   case lltok::kw_dso_preemptable:
+    ExplicitDSOPreemption = true;
     DSOLocal = false;
     Lex.Lex();
     break;
@@ -5642,14 +5648,14 @@
   unsigned Linkage;
   unsigned Visibility;
   unsigned DLLStorageClass;
-  bool DSOLocal;
+  bool ExplicitDSOPreemption, DSOLocal;
   AttrBuilder RetAttrs;
   unsigned CC;
   bool HasLinkage;
   Type *RetType = nullptr;
   LocTy RetTypeLoc = Lex.getLoc();
   if (parseOptionalLinkage(Linkage, HasLinkage, Visibility, DLLStorageClass,
-                           DSOLocal) ||
+                           ExplicitDSOPreemption, DSOLocal) ||
       parseOptionalCallingConv(CC) || parseOptionalReturnAttrs(RetAttrs) ||
       parseType(RetType, RetTypeLoc, true /*void allowed*/))
     return true;
@@ -5822,7 +5828,7 @@
     NumberedVals.push_back(Fn);
 
   Fn->setLinkage((GlobalValue::LinkageTypes)Linkage);
-  maybeSetDSOLocal(DSOLocal, *Fn);
+  Fn->setDSOLocal(ExplicitDSOPreemption ? DSOLocal : IsDefine);
   Fn->setVisibility((GlobalValue::VisibilityTypes)Visibility);
   Fn->setDLLStorageClass((GlobalValue::DLLStorageClassTypes)DLLStorageClass);
   Fn->setCallingConv(CC);
diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -3441,8 +3441,15 @@
 
 static void PrintDSOLocation(const GlobalValue &GV,
                              formatted_raw_ostream &Out) {
-  if (GV.isDSOLocal() && !GV.isImplicitDSOLocal())
-    Out << "dso_local ";
+  bool Default =
+      GV.isImplicitDSOLocal() || (isa<Function>(GV) && !GV.isDeclaration());
+  if (GV.isDSOLocal()) {
+    if (!Default)
+      Out << "dso_local ";
+  } else {
+    if (Default)
+      Out << "dso_preemptable ";
+  }
 }
 
 static void PrintDLLStorageClass(GlobalValue::DLLStorageClassTypes SCT,