2 files changed, 41 insertions, 24 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index a489aaed459..f8d6f785a10 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3029,7 +3029,8 @@ std::error_code BitcodeReader::parseModule(bool Resume,
 
 
     // Read a record.
-    switch (Stream.readRecord(Entry.ID, Record)) {
+    auto BitCode = Stream.readRecord(Entry.ID, Record);
+    switch (BitCode) {
     default: break;  // Default behavior, ignore unknown content.
     case bitc::MODULE_CODE_VERSION: {  // VERSION: [version#]
       if (Record.size() < 1)
@@ -3268,36 +3269,51 @@ std::error_code BitcodeReader::parseModule(bool Resume,
       }
       break;
     }
-    // ALIAS: [alias type, aliasee val#, linkage]
-    // ALIAS: [alias type, aliasee val#, linkage, visibility, dllstorageclass]
-    case bitc::MODULE_CODE_ALIAS: {
-      if (Record.size() < 3)
+    // ALIAS: [alias type, addrspace, aliasee val#, linkage]
+    // ALIAS: [alias type, addrspace, aliasee val#, linkage, visibility, dllstorageclass]
+    case bitc::MODULE_CODE_ALIAS:
+    case bitc::MODULE_CODE_ALIAS_OLD: {
+      bool NewRecord = BitCode == bitc::MODULE_CODE_ALIAS;
+      if (Record.size() < (3 + NewRecord))
         return error("Invalid record");
-      Type *Ty = getTypeByID(Record[0]);
+      unsigned OpNum = 0;
+      Type *Ty = getTypeByID(Record[OpNum++]);
       if (!Ty)
         return error("Invalid record");
-      auto *PTy = dyn_cast<PointerType>(Ty);
-      if (!PTy)
-        return error("Invalid type for value");
 
-      auto *NewGA =
-          GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(),
-                              getDecodedLinkage(Record[2]), "", TheModule);
+      unsigned AddrSpace;
+      if (!NewRecord) {
+        auto *PTy = dyn_cast<PointerType>(Ty);
+        if (!PTy)
+          return error("Invalid type for value");
+        Ty = PTy->getElementType();
+        AddrSpace = PTy->getAddressSpace();
+      } else {
+        AddrSpace = Record[OpNum++];
+      }
+
+      auto Val = Record[OpNum++];
+      auto Linkage = Record[OpNum++];
+      auto *NewGA = GlobalAlias::create(
+          Ty, AddrSpace, getDecodedLinkage(Linkage), "", TheModule);
       // Old bitcode files didn't have visibility field.
       // Local linkage must have default visibility.
-      if (Record.size() > 3 && !NewGA->hasLocalLinkage())
-        // FIXME: Change to an error if non-default in 4.0.
-        NewGA->setVisibility(getDecodedVisibility(Record[3]));
-      if (Record.size() > 4)
-        NewGA->setDLLStorageClass(getDecodedDLLStorageClass(Record[4]));
+      if (OpNum != Record.size()) {
+        auto VisInd = OpNum++;
+        if (!NewGA->hasLocalLinkage())
+          // FIXME: Change to an error if non-default in 4.0.
+          NewGA->setVisibility(getDecodedVisibility(Record[VisInd]));
+      }
+      if (OpNum != Record.size())
+        NewGA->setDLLStorageClass(getDecodedDLLStorageClass(Record[OpNum++]));
       else
-        upgradeDLLImportExportLinkage(NewGA, Record[2]);
-      if (Record.size() > 5)
-        NewGA->setThreadLocalMode(getDecodedThreadLocalMode(Record[5]));
-      if (Record.size() > 6)
-        NewGA->setUnnamedAddr(Record[6]);
+        upgradeDLLImportExportLinkage(NewGA, Linkage);
+      if (OpNum != Record.size())
+        NewGA->setThreadLocalMode(getDecodedThreadLocalMode(Record[OpNum++]));
+      if (OpNum != Record.size())
+        NewGA->setUnnamedAddr(Record[OpNum++]);
       ValueList.push_back(NewGA);
-      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
+      AliasInits.push_back(std::make_pair(NewGA, Val));
       break;
     }
     /// MODULE_CODE_PURGEVALS: [numvals]
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 1acb7d02d86..3ab738a2c02 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -756,7 +756,8 @@ static uint64_t WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   // Emit the alias information.
   for (const GlobalAlias &A : M->aliases()) {
     // ALIAS: [alias type, aliasee val#, linkage, visibility]
-    Vals.push_back(VE.getTypeID(A.getType()));
+    Vals.push_back(VE.getTypeID(A.getValueType()));
+    Vals.push_back(A.getType()->getAddressSpace());
     Vals.push_back(VE.getValueID(A.getAliasee()));
     Vals.push_back(getEncodedLinkage(A));
     Vals.push_back(getEncodedVisibility(A));