1 files changed, 152 insertions, 62 deletions

diff --git a/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp b/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
index d3b5cf2d9f7b..e67b02405a3a 100644
--- a/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
+++ b/contrib/llvm-project/llvm/lib/Object/COFFImportFile.cpp
@@ -12,6 +12,8 @@
 
 #include "llvm/Object/COFFImportFile.h"
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/ArchiveWriter.h"
@@ -52,18 +54,12 @@ StringRef COFFImportFile::getFileFormatName() const {
   }
 }
 
-StringRef COFFImportFile::getExportName() const {
-  const coff_import_header *hdr = getCOFFImportHeader();
-  StringRef name = Data.getBuffer().substr(sizeof(*hdr)).split('\0').first;
-
+static StringRef applyNameType(ImportNameType Type, StringRef name) {
   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;
+  switch (Type) {
   case IMPORT_NAME_NOPREFIX:
     name = ltrim1(name, "?@_");
     break;
@@ -71,6 +67,24 @@ StringRef COFFImportFile::getExportName() const {
     name = ltrim1(name, "?@_");
     name = name.substr(0, name.find('@'));
     break;
+  default:
+    break;
+  }
+  return name;
+}
+
+StringRef COFFImportFile::getExportName() const {
+  const coff_import_header *hdr = getCOFFImportHeader();
+  StringRef name = Data.getBuffer().substr(sizeof(*hdr)).split('\0').first;
+
+  switch (hdr->getNameType()) {
+  case IMPORT_ORDINAL:
+    name = "";
+    break;
+  case IMPORT_NAME_NOPREFIX:
+  case IMPORT_NAME_UNDECORATE:
+    name = applyNameType(static_cast<ImportNameType>(hdr->getNameType()), name);
+    break;
   case IMPORT_NAME_EXPORTAS: {
     // Skip DLL name
     name = Data.getBuffer().substr(sizeof(*hdr) + name.size() + 1);
@@ -84,6 +98,27 @@ StringRef COFFImportFile::getExportName() const {
   return name;
 }
 
+Error COFFImportFile::printSymbolName(raw_ostream &OS, DataRefImpl Symb) const {
+  switch (Symb.p) {
+  case ImpSymbol:
+    OS << "__imp_";
+    break;
+  case ECAuxSymbol:
+    OS << "__imp_aux_";
+    break;
+  }
+  const char *Name = Data.getBufferStart() + sizeof(coff_import_header);
+  if (Symb.p != ECThunkSymbol && COFF::isArm64EC(getMachine())) {
+    if (std::optional<std::string> DemangledName =
+            getArm64ECDemangledFunctionName(Name)) {
+      OS << StringRef(*DemangledName);
+      return Error::success();
+    }
+  }
+  OS << StringRef(Name);
+  return Error::success();
+}
+
 static uint16_t getImgRelRelocation(MachineTypes Machine) {
   switch (Machine) {
   default:
@@ -623,10 +658,14 @@ NewArchiveMember ObjectFactory::createWeakExternal(StringRef Sym,
 
 Error writeImportLibrary(StringRef ImportName, StringRef Path,
                          ArrayRef<COFFShortExport> Exports,
-                         MachineTypes Machine, bool MinGW) {
+                         MachineTypes Machine, bool MinGW,
+                         ArrayRef<COFFShortExport> NativeExports) {
 
-  MachineTypes NativeMachine =
-      isArm64EC(Machine) ? IMAGE_FILE_MACHINE_ARM64 : Machine;
+  MachineTypes NativeMachine = Machine;
+  if (isArm64EC(Machine)) {
+    NativeMachine = IMAGE_FILE_MACHINE_ARM64;
+    Machine = IMAGE_FILE_MACHINE_ARM64EC;
+  }
 
   std::vector<NewArchiveMember> Members;
   ObjectFactory OF(llvm::sys::path::filename(ImportName), NativeMachine);
@@ -640,66 +679,117 @@ Error writeImportLibrary(StringRef ImportName, StringRef Path,
   std::vector<uint8_t> NullThunk;
   Members.push_back(OF.createNullThunk(NullThunk));
 
-  for (const COFFShortExport &E : Exports) {
-    if (E.Private)
-      continue;
-
-    ImportType ImportType = IMPORT_CODE;
-    if (E.Data)
-      ImportType = IMPORT_DATA;
-    if (E.Constant)
-      ImportType = IMPORT_CONST;
-
-    StringRef SymbolName = E.SymbolName.empty() ? E.Name : E.SymbolName;
-    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));
-      Members.push_back(
-          OF.createWeakExternal(E.AliasTarget, Name, true, Machine));
-      continue;
-    }
+  auto addExports = [&](ArrayRef<COFFShortExport> Exp,
+                        MachineTypes M) -> Error {
+    StringMap<std::string> RegularImports;
+    struct Deferred {
+      std::string Name;
+      ImportType ImpType;
+      const COFFShortExport *Export;
+    };
+    SmallVector<Deferred, 0> Renames;
+    for (const COFFShortExport &E : Exp) {
+      if (E.Private)
+        continue;
+
+      ImportType ImportType = IMPORT_CODE;
+      if (E.Data)
+        ImportType = IMPORT_DATA;
+      if (E.Constant)
+        ImportType = IMPORT_CONST;
+
+      StringRef SymbolName = E.SymbolName.empty() ? E.Name : E.SymbolName;
+      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);
+      }
 
-    ImportNameType NameType;
-    std::string ExportName;
-    if (E.Noname) {
-      NameType = IMPORT_ORDINAL;
-    } else {
-      NameType = getNameType(SymbolName, E.Name, Machine, MinGW);
-    }
+      ImportNameType NameType;
+      std::string ExportName;
+      if (E.Noname) {
+        NameType = IMPORT_ORDINAL;
+      } else if (!E.ExportAs.empty()) {
+        NameType = IMPORT_NAME_EXPORTAS;
+        ExportName = E.ExportAs;
+      } else if (!E.ImportName.empty()) {
+        // If we need to import from a specific ImportName, we may need to use
+        // a weak alias (which needs another import to point at). But if we can
+        // express ImportName based on the symbol name and a specific NameType,
+        // prefer that over an alias.
+        if (Machine == IMAGE_FILE_MACHINE_I386 &&
+            applyNameType(IMPORT_NAME_UNDECORATE, Name) == E.ImportName)
+          NameType = IMPORT_NAME_UNDECORATE;
+        else if (Machine == IMAGE_FILE_MACHINE_I386 &&
+                 applyNameType(IMPORT_NAME_NOPREFIX, Name) == E.ImportName)
+          NameType = IMPORT_NAME_NOPREFIX;
+        else if (isArm64EC(M)) {
+          NameType = IMPORT_NAME_EXPORTAS;
+          ExportName = E.ImportName;
+        } else if (Name == E.ImportName)
+          NameType = IMPORT_NAME;
+        else {
+          Deferred D;
+          D.Name = Name;
+          D.ImpType = ImportType;
+          D.Export = &E;
+          Renames.push_back(D);
+          continue;
+        }
+      } else {
+        NameType = getNameType(SymbolName, E.Name, M, 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()) {
+      // On ARM64EC, use EXPORTAS to import demangled name for mangled symbols.
+      if (ImportType == IMPORT_CODE && isArm64EC(M)) {
+        if (std::optional<std::string> MangledName =
+                getArm64ECMangledFunctionName(Name)) {
+          if (!E.Noname && ExportName.empty()) {
+            NameType = IMPORT_NAME_EXPORTAS;
+            ExportName.swap(Name);
+          }
+          Name = std::move(*MangledName);
+        } else if (!E.Noname && ExportName.empty()) {
           NameType = IMPORT_NAME_EXPORTAS;
-          ExportName.swap(Name);
+          ExportName = std::move(*getArm64ECDemangledFunctionName(Name));
         }
-        Name = std::move(*MangledName);
-      } else if (ExportName.empty()) {
-        NameType = IMPORT_NAME_EXPORTAS;
-        ExportName = std::move(*getArm64ECDemangledFunctionName(Name));
+      }
+
+      RegularImports[applyNameType(NameType, Name)] = Name;
+      Members.push_back(OF.createShortImport(Name, E.Ordinal, ImportType,
+                                             NameType, ExportName, M));
+    }
+    for (const auto &D : Renames) {
+      auto It = RegularImports.find(D.Export->ImportName);
+      if (It != RegularImports.end()) {
+        // We have a regular import entry for a symbol with the name we
+        // want to reference; produce an alias pointing at that.
+        StringRef Symbol = It->second;
+        if (D.ImpType == IMPORT_CODE)
+          Members.push_back(OF.createWeakExternal(Symbol, D.Name, false, M));
+        Members.push_back(OF.createWeakExternal(Symbol, D.Name, true, M));
+      } else {
+        Members.push_back(OF.createShortImport(D.Name, D.Export->Ordinal,
+                                               D.ImpType, IMPORT_NAME_EXPORTAS,
+                                               D.Export->ImportName, M));
       }
     }
+    return Error::success();
+  };
 
-    Members.push_back(OF.createShortImport(Name, E.Ordinal, ImportType,
-                                           NameType, ExportName, Machine));
-  }
+  if (Error e = addExports(Exports, Machine))
+    return e;
+  if (Error e = addExports(NativeExports, NativeMachine))
+    return e;
 
   return writeArchive(Path, Members, SymtabWritingMode::NormalSymtab,
-                      MinGW ? object::Archive::K_GNU : object::Archive::K_COFF,
+                      object::Archive::K_COFF,
                       /*Deterministic*/ true, /*Thin*/ false,
                       /*OldArchiveBuf*/ nullptr, isArm64EC(Machine));
 }