3 files changed, 35 insertions, 3 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 0e74fe3..b8ebe8f 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3658,6 +3658,8 @@ std::error_code BitcodeReader::parseModule(uint64_t ResumeBit,
     }
     // ALIAS: [alias type, addrspace, aliasee val#, linkage]
     // ALIAS: [alias type, addrspace, aliasee val#, linkage, visibility, dllstorageclass]
+    // IFUNC: [alias type, addrspace, aliasee val#, linkage, visibility, dllstorageclass]
+    case bitc::MODULE_CODE_IFUNC:
     case bitc::MODULE_CODE_ALIAS:
     case bitc::MODULE_CODE_ALIAS_OLD: {
       bool NewRecord = BitCode != bitc::MODULE_CODE_ALIAS_OLD;
@@ -3684,10 +3686,11 @@ std::error_code BitcodeReader::parseModule(uint64_t ResumeBit,
       GlobalIndirectSymbol *NewGA;
       if (BitCode == bitc::MODULE_CODE_ALIAS ||
           BitCode == bitc::MODULE_CODE_ALIAS_OLD)
-        NewGA = GlobalAlias::create(
-          Ty, AddrSpace, getDecodedLinkage(Linkage), "", TheModule);
+        NewGA = GlobalAlias::create(Ty, AddrSpace, getDecodedLinkage(Linkage),
+                                    "", TheModule);
       else
-        llvm_unreachable("Not an alias!");
+        NewGA = GlobalIFunc::create(Ty, AddrSpace, getDecodedLinkage(Linkage),
+                                    "", nullptr, TheModule);
       // Old bitcode files didn't have visibility field.
       // Local linkage must have default visibility.
       if (OpNum != Record.size()) {
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index cbaaea8..23cd088 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -809,6 +809,18 @@ static uint64_t WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
     Vals.clear();
   }
 
+  // Emit the ifunc information.
+  for (const GlobalIFunc &I : M->ifuncs()) {
+    // IFUNC: [ifunc type, address space, resolver val#, linkage, visibility]
+    Vals.push_back(VE.getTypeID(I.getValueType()));
+    Vals.push_back(I.getType()->getAddressSpace());
+    Vals.push_back(VE.getValueID(I.getResolver()));
+    Vals.push_back(getEncodedLinkage(I));
+    Vals.push_back(getEncodedVisibility(I));
+    Stream.EmitRecord(bitc::MODULE_CODE_IFUNC, Vals);
+    Vals.clear();
+  }
+
   // Emit the module's source file name.
   {
     StringEncoding Bits = getStringEncoding(M->getSourceFileName().data(),
diff --git a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
index 91b523f..ff87052 100644
--- a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -86,6 +86,9 @@ static OrderMap orderModule(const Module &M) {
   for (const GlobalAlias &A : M.aliases())
     if (!isa<GlobalValue>(A.getAliasee()))
       orderValue(A.getAliasee(), OM);
+  for (const GlobalIFunc &I : M.ifuncs())
+    if (!isa<GlobalValue>(I.getResolver()))
+      orderValue(I.getResolver(), OM);
   for (const Function &F : M) {
     for (const Use &U : F.operands())
       if (!isa<GlobalValue>(U.get()))
@@ -105,6 +108,8 @@ static OrderMap orderModule(const Module &M) {
     orderValue(&F, OM);
   for (const GlobalAlias &A : M.aliases())
     orderValue(&A, OM);
+  for (const GlobalIFunc &I : M.ifuncs())
+    orderValue(&I, OM);
   for (const GlobalVariable &G : M.globals())
     orderValue(&G, OM);
   OM.LastGlobalValueID = OM.size();
@@ -261,11 +266,15 @@ static UseListOrderStack predictUseListOrder(const Module &M) {
     predictValueUseListOrder(&F, nullptr, OM, Stack);
   for (const GlobalAlias &A : M.aliases())
     predictValueUseListOrder(&A, nullptr, OM, Stack);
+  for (const GlobalIFunc &I : M.ifuncs())
+    predictValueUseListOrder(&I, nullptr, OM, Stack);
   for (const GlobalVariable &G : M.globals())
     if (G.hasInitializer())
       predictValueUseListOrder(G.getInitializer(), nullptr, OM, Stack);
   for (const GlobalAlias &A : M.aliases())
     predictValueUseListOrder(A.getAliasee(), nullptr, OM, Stack);
+  for (const GlobalIFunc &I : M.ifuncs())
+    predictValueUseListOrder(I.getResolver(), nullptr, OM, Stack);
   for (const Function &F : M) {
     for (const Use &U : F.operands())
       predictValueUseListOrder(U.get(), nullptr, OM, Stack);
@@ -298,6 +307,10 @@ ValueEnumerator::ValueEnumerator(const Module &M,
   for (const GlobalAlias &GA : M.aliases())
     EnumerateValue(&GA);
 
+  // Enumerate the ifuncs.
+  for (const GlobalIFunc &GIF : M.ifuncs())
+    EnumerateValue(&GIF);
+
   // Remember what is the cutoff between globalvalue's and other constants.
   unsigned FirstConstant = Values.size();
 
@@ -310,6 +323,10 @@ ValueEnumerator::ValueEnumerator(const Module &M,
   for (const GlobalAlias &GA : M.aliases())
     EnumerateValue(GA.getAliasee());
 
+  // Enumerate the ifunc resolvers.
+  for (const GlobalIFunc &GIF : M.ifuncs())
+    EnumerateValue(GIF.getResolver());
+
   // Enumerate any optional Function data.
   for (const Function &F : M)
     for (const Use &U : F.operands())