Index: include/llvm/IR/GlobalAlias.h
===================================================================
--- include/llvm/IR/GlobalAlias.h
+++ include/llvm/IR/GlobalAlias.h
@@ -36,6 +36,16 @@
               const Twine &Name, Constant *Aliasee, Module *Parent);
 
 public:
+  /// Returns true if given alias has ifunc type.
+  bool isIFunc() const {
+    return getGlobalValueSubClassData();
+  }
+
+  /// Set isIFunc property.
+  void setIFunc(bool IsIFunc) {
+    setGlobalValueSubClassData(IsIFunc);
+  }
+
   // allocate space for exactly one operand
   void *operator new(size_t s) {
     return User::operator new(s, 1);
@@ -77,6 +87,10 @@
   ///
   void eraseFromParent() override;
 
+  /// Copy all additional attributes (those not needed to create a GlobalAlias)
+  /// from the Src to this one.
+  void copyAttributesFrom(const GlobalValue *Src) override;
+
   /// These methods retrive and set alias target.
   void setAliasee(Constant *Aliasee);
   const Constant *getAliasee() const {
Index: lib/AsmParser/LLLexer.cpp
===================================================================
--- lib/AsmParser/LLLexer.cpp
+++ lib/AsmParser/LLLexer.cpp
@@ -609,6 +609,7 @@
   KEYWORD(convergent);
   KEYWORD(dereferenceable);
   KEYWORD(dereferenceable_or_null);
+  KEYWORD(ifunc);
   KEYWORD(inlinehint);
   KEYWORD(inreg);
   KEYWORD(jumptable);
Index: lib/AsmParser/LLParser.cpp
===================================================================
--- lib/AsmParser/LLParser.cpp
+++ lib/AsmParser/LLParser.cpp
@@ -678,6 +678,12 @@
     return Error(NameLoc,
                  "symbol with local linkage must have default visibility");
 
+  bool IFunc = false;
+  if (Lex.getKind() == lltok::kw_ifunc) {
+    IFunc = true;
+    Lex.Lex();
+  }
+
   Type *Ty;
   LocTy ExplicitTypeLoc = Lex.getLoc();
   if (ParseType(Ty) ||
@@ -739,6 +745,7 @@
   GA->setVisibility((GlobalValue::VisibilityTypes)Visibility);
   GA->setDLLStorageClass((GlobalValue::DLLStorageClassTypes)DLLStorageClass);
   GA->setUnnamedAddr(UnnamedAddr);
+  GA->setIFunc(IFunc);
 
   if (Name.empty())
     NumberedVals.push_back(GA.get());
Index: lib/AsmParser/LLToken.h
===================================================================
--- lib/AsmParser/LLToken.h
+++ lib/AsmParser/LLToken.h
@@ -115,6 +115,7 @@
     kw_convergent,
     kw_dereferenceable,
     kw_dereferenceable_or_null,
+    kw_ifunc,
     kw_inlinehint,
     kw_inreg,
     kw_jumptable,
Index: lib/Bitcode/Reader/BitcodeReader.cpp
===================================================================
--- lib/Bitcode/Reader/BitcodeReader.cpp
+++ lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3624,6 +3624,8 @@
         NewGA->setThreadLocalMode(getDecodedThreadLocalMode(Record[OpNum++]));
       if (OpNum != Record.size())
         NewGA->setUnnamedAddr(Record[OpNum++]);
+      if (OpNum != Record.size())
+        NewGA->setIFunc(Record[OpNum++]);
       ValueList.push_back(NewGA);
       AliasInits.push_back(std::make_pair(NewGA, Val));
       break;
Index: lib/Bitcode/Writer/BitcodeWriter.cpp
===================================================================
--- lib/Bitcode/Writer/BitcodeWriter.cpp
+++ lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -771,6 +771,7 @@
     Vals.push_back(getEncodedDLLStorageClass(A));
     Vals.push_back(getEncodedThreadLocalMode(A));
     Vals.push_back(A.hasUnnamedAddr());
+    Vals.push_back(A.isIFunc());
     unsigned AbbrevToUse = 0;
     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
     Vals.clear();
Index: lib/CodeGen/AsmPrinter/AsmPrinter.cpp
===================================================================
--- lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1189,8 +1189,11 @@
 
     // Set the symbol type to function if the alias has a function type.
     // This affects codegen when the aliasee is not a function.
-    if (Alias.getType()->getPointerElementType()->isFunctionTy())
+    if (Alias.getType()->getPointerElementType()->isFunctionTy()) {
       OutStreamer->EmitSymbolAttribute(Name, MCSA_ELF_TypeFunction);
+      if (Alias.isIFunc())
+        OutStreamer->EmitSymbolAttribute(Name, MCSA_ELF_TypeIndFunction);
+    }
 
     EmitVisibility(Name, Alias.getVisibility());
 
Index: lib/IR/AsmWriter.cpp
===================================================================
--- lib/IR/AsmWriter.cpp
+++ lib/IR/AsmWriter.cpp
@@ -2458,6 +2458,9 @@
 
   Out << "alias ";
 
+  if (GA->isIFunc())
+    Out << "ifunc ";
+
   TypePrinter.print(GA->getValueType(), Out);
 
   Out << ", ";
Index: lib/IR/Globals.cpp
===================================================================
--- lib/IR/Globals.cpp
+++ lib/IR/Globals.cpp
@@ -241,6 +241,8 @@
 
   if (ParentModule)
     ParentModule->getAliasList().push_back(this);
+
+  setIFunc(false);
 }
 
 GlobalAlias *GlobalAlias::create(Type *Ty, unsigned AddressSpace,
@@ -289,3 +291,9 @@
          "Alias and aliasee types should match!");
   setOperand(0, Aliasee);
 }
+
+void GlobalAlias::copyAttributesFrom(const GlobalValue *Src) {
+  GlobalValue::copyAttributesFrom(Src);
+  if (const auto *GV = dyn_cast<GlobalAlias>(Src))
+    setIFunc(GV->isIFunc());
+}
Index: test/Assembler/ifunc-alias.ll
===================================================================
--- /dev/null
+++ test/Assembler/ifunc-alias.ll
@@ -0,0 +1,14 @@
+; RUN: llvm-as < %s | llvm-dis | FileCheck %s --check-prefix=CHECK-LLVM
+; RUN: llvm-as < %s -o - | llc -filetype=asm | FileCheck %s --check-prefix=CHECK-ASM
+
+target triple = "x86_64-unknown-linux-gnu"
+
+@foo = linkonce alias ifunc i32 (i32), bitcast (i64 ()* @foo_ifunc to i32 (i32)*)
+; CHECK-LLVM: @foo = linkonce alias ifunc i32 (i32), bitcast (i64 ()* @foo_ifunc to i32 (i32)*)
+; CHECK-ASM: .type   foo,@gnu_indirect_function
+
+define internal i64 @foo_ifunc() {
+entry:
+  ret i64 0
+}
+; CHECK-LLVM: define internal i64 @foo_ifunc()