1 files changed, 87 insertions, 27 deletions

diff --git a/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp b/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
index 60556c149bf7..d3b5cf2d9f7b 100644
--- a/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
+++ b/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
@@ -52,6 +52,38 @@ StringRef COFFImportFile::getFileFormatName() const {
   }
 }
 
+StringRef COFFImportFile::getExportName() const {
+  const coff_import_header *hdr = getCOFFImportHeader();
+  StringRef name = Data.getBuffer().substr(sizeof(*hdr)).split('\0').first;
+
+  auto ltrim1 = [](StringRef s, StringRef chars) {
+    return !s.empty() && chars.contains(s[0]) ? s.substr(1) : s;
+  };
+
+  switch (hdr->getNameType()) {
+  case IMPORT_ORDINAL:
+    name = "";
+    break;
+  case IMPORT_NAME_NOPREFIX:
+    name = ltrim1(name, "?@_");
+    break;
+  case IMPORT_NAME_UNDECORATE:
+    name = ltrim1(name, "?@_");
+    name = name.substr(0, name.find('@'));
+    break;
+  case IMPORT_NAME_EXPORTAS: {
+    // Skip DLL name
+    name = Data.getBuffer().substr(sizeof(*hdr) + name.size() + 1);
+    name = name.split('\0').second.split('\0').first;
+    break;
+  }
+  default:
+    break;
+  }
+
+  return name;
+}
+
 static uint16_t getImgRelRelocation(MachineTypes Machine) {
   switch (Machine) {
   default:
@@ -76,7 +108,7 @@ template <class T> static void append(std::vector<uint8_t> &B, const T &Data) {
 }
 
 static void writeStringTable(std::vector<uint8_t> &B,
-                             ArrayRef<const std::string> Strings) {
+                             ArrayRef<const std::string_view> Strings) {
   // The COFF string table consists of a 4-byte value which is the size of the
   // table, including the length field itself.  This value is followed by the
   // string content itself, which is an array of null-terminated C-style
@@ -139,9 +171,6 @@ static Expected<std::string> replace(StringRef S, StringRef From,
   return (Twine(S.substr(0, Pos)) + To + S.substr(Pos + From.size())).str();
 }
 
-static const std::string NullImportDescriptorSymbolName =
-    "__NULL_IMPORT_DESCRIPTOR";
-
 namespace {
 // This class constructs various small object files necessary to support linking
 // symbols imported from a DLL.  The contents are pretty strictly defined and
@@ -160,8 +189,9 @@ class ObjectFactory {
 public:
   ObjectFactory(StringRef S, MachineTypes M)
       : NativeMachine(M), ImportName(S), Library(llvm::sys::path::stem(S)),
-        ImportDescriptorSymbolName(("__IMPORT_DESCRIPTOR_" + Library).str()),
-        NullThunkSymbolName(("\x7f" + Library + "_NULL_THUNK_DATA").str()) {}
+        ImportDescriptorSymbolName((ImportDescriptorPrefix + Library).str()),
+        NullThunkSymbolName(
+            (NullThunkDataPrefix + Library + NullThunkDataSuffix).str()) {}
 
   // Creates an Import Descriptor.  This is a small object file which contains a
   // reference to the terminators and contains the library name (entry) for the
@@ -183,6 +213,7 @@ public:
   // Library Format.
   NewArchiveMember createShortImport(StringRef Sym, uint16_t Ordinal,
                                      ImportType Type, ImportNameType NameType,
+                                     StringRef ExportName,
                                      MachineTypes Machine);
 
   // Create a weak external file which is described in PE/COFF Aux Format 3.
@@ -474,12 +505,13 @@ NewArchiveMember ObjectFactory::createNullThunk(std::vector<uint8_t> &Buffer) {
   return {MemoryBufferRef{F, ImportName}};
 }
 
-NewArchiveMember ObjectFactory::createShortImport(StringRef Sym,
-                                                  uint16_t Ordinal,
-                                                  ImportType ImportType,
-                                                  ImportNameType NameType,
-                                                  MachineTypes Machine) {
+NewArchiveMember
+ObjectFactory::createShortImport(StringRef Sym, uint16_t Ordinal,
+                                 ImportType ImportType, ImportNameType NameType,
+                                 StringRef ExportName, MachineTypes Machine) {
   size_t ImpSize = ImportName.size() + Sym.size() + 2; // +2 for NULs
+  if (!ExportName.empty())
+    ImpSize += ExportName.size() + 1;
   size_t Size = sizeof(coff_import_header) + ImpSize;
   char *Buf = Alloc.Allocate<char>(Size);
   memset(Buf, 0, Size);
@@ -499,6 +531,10 @@ NewArchiveMember ObjectFactory::createShortImport(StringRef Sym,
   memcpy(P, Sym.data(), Sym.size());
   P += Sym.size() + 1;
   memcpy(P, ImportName.data(), ImportName.size());
+  if (!ExportName.empty()) {
+    P += ImportName.size() + 1;
+    memcpy(P, ExportName.data(), ExportName.size());
+  }
 
   return {MemoryBufferRef(StringRef(Buf, Size), ImportName)};
 }
@@ -615,27 +651,51 @@ Error writeImportLibrary(StringRef ImportName, StringRef Path,
       ImportType = IMPORT_CONST;
 
     StringRef SymbolName = E.SymbolName.empty() ? E.Name : E.SymbolName;
-    ImportNameType NameType = E.Noname
-                                  ? IMPORT_ORDINAL
-                                  : getNameType(SymbolName, E.Name,
-                                                Machine, MinGW);
-    Expected<std::string> Name = E.ExtName.empty()
-                                     ? std::string(SymbolName)
-                                     : replace(SymbolName, E.Name, E.ExtName);
-
-    if (!Name)
-      return Name.takeError();
-
-    if (!E.AliasTarget.empty() && *Name != E.AliasTarget) {
+    std::string Name;
+
+    if (E.ExtName.empty()) {
+      Name = std::string(SymbolName);
+    } else {
+      Expected<std::string> ReplacedName =
+          replace(SymbolName, E.Name, E.ExtName);
+      if (!ReplacedName)
+        return ReplacedName.takeError();
+      Name.swap(*ReplacedName);
+    }
+
+    if (!E.AliasTarget.empty() && Name != E.AliasTarget) {
       Members.push_back(
-          OF.createWeakExternal(E.AliasTarget, *Name, false, Machine));
+          OF.createWeakExternal(E.AliasTarget, Name, false, Machine));
       Members.push_back(
-          OF.createWeakExternal(E.AliasTarget, *Name, true, Machine));
+          OF.createWeakExternal(E.AliasTarget, Name, true, Machine));
       continue;
     }
 
-    Members.push_back(
-        OF.createShortImport(*Name, E.Ordinal, ImportType, NameType, Machine));
+    ImportNameType NameType;
+    std::string ExportName;
+    if (E.Noname) {
+      NameType = IMPORT_ORDINAL;
+    } else {
+      NameType = getNameType(SymbolName, E.Name, Machine, MinGW);
+    }
+
+    // On ARM64EC, use EXPORTAS to import demangled name for mangled symbols.
+    if (ImportType == IMPORT_CODE && isArm64EC(Machine)) {
+      if (std::optional<std::string> MangledName =
+              getArm64ECMangledFunctionName(Name)) {
+        if (ExportName.empty()) {
+          NameType = IMPORT_NAME_EXPORTAS;
+          ExportName.swap(Name);
+        }
+        Name = std::move(*MangledName);
+      } else if (ExportName.empty()) {
+        NameType = IMPORT_NAME_EXPORTAS;
+        ExportName = std::move(*getArm64ECDemangledFunctionName(Name));
+      }
+    }
+
+    Members.push_back(OF.createShortImport(Name, E.Ordinal, ImportType,
+                                           NameType, ExportName, Machine));
   }
 
   return writeArchive(Path, Members, SymtabWritingMode::NormalSymtab,