ModuleInterface/Serialization: allow library authors to define a custom module version number

include/swift/AST/Module.h

@@ -356,6 +356,14 @@ class ModuleDecl : public DeclContext, public TypeDecl {
     ModuleABIName = name;
   }
 
+  /// User-defined module version number.
+  llvm::VersionTuple UserModuleVersion;
+  void setUserModuleVersion(llvm::VersionTuple UserVer) {
+    UserModuleVersion = UserVer;
+  }
+  llvm::VersionTuple getUserModuleVersion() const {
+    return UserModuleVersion;
+  }
 private:
   /// A cache of this module's underlying module and required bystander if it's
   /// an underscored cross-import overlay.

include/swift/Frontend/FrontendOptions.h

@@ -84,6 +84,9 @@ class FrontendOptions {
   /// For these modules, we should prefer using Swift interface when importing them.
   std::vector<std::string> PreferInterfaceForModules;
 
+  /// User-defined module version number.
+  llvm::VersionTuple UserModuleVersion;
+
   /// Emit index data for imported serialized swift system modules.
   bool IndexSystemModules = false;
 

include/swift/Option/Options.td

@@ -1172,6 +1172,11 @@ def working_directory : Separate<["-"], "working-directory">,
 def working_directory_EQ : Joined<["-"], "working-directory=">,
   Alias<working_directory>;
 
+def user_module_version : Separate<["-"], "user-module-version">,
+  Flags<[FrontendOption, ModuleInterfaceOption]>,
+  HelpText<"Module version specified from Swift module authors">,
+  MetaVarName<"<vers>">;
+
 // VFS
 
 def vfsoverlay : JoinedOrSeparate<["-"], "vfsoverlay">,

include/swift/Serialization/SerializationOptions.h

@@ -14,6 +14,7 @@
 #define SWIFT_SERIALIZATION_SERIALIZATIONOPTIONS_H
 
 #include "swift/Basic/LLVM.h"
+#include "llvm/Support/VersionTuple.h"
 
 namespace swift {
 
@@ -32,6 +33,7 @@ namespace swift {
     const char *SourceInfoOutputPath = nullptr;
     std::string SymbolGraphOutputDir;
     bool SkipSymbolGraphInheritedDocs = true;
+    llvm::VersionTuple UserModuleVersion;
 
     StringRef GroupInfoPath;
     StringRef ImportedHeader;

include/swift/Serialization/Validation.h

@@ -79,6 +79,7 @@ struct ValidationInfo {
   StringRef shortVersion = {};
   StringRef miscVersion = {};
   version::Version compatibilityVersion = {};
+  llvm::VersionTuple userModuleVersion;
   size_t bytes = 0;
   Status status = Status::Malformed;
 };

lib/Frontend/ArgsToFrontendOptionsConverter.cpp

@@ -99,6 +99,13 @@ bool ArgsToFrontendOptionsConverter::convert(
     Opts.BadFileDescriptorRetryCount = limit;
   }
 
+  if (auto A = Args.getLastArg(OPT_user_module_version)) {
+    if (Opts.UserModuleVersion.tryParse(StringRef(A->getValue()))) {
+      Diags.diagnose(SourceLoc(), diag::error_invalid_arg_value,
+                     A->getAsString(Args), A->getValue());
+    }
+  }
+
   Opts.DisableImplicitModules |= Args.hasArg(OPT_disable_implicit_swift_modules);
 
   Opts.ImportPrescan |= Args.hasArg(OPT_import_prescan);

lib/Frontend/Frontend.cpp

@@ -154,6 +154,7 @@ SerializationOptions CompilerInvocation::computeSerializationOptions(
   if (opts.SerializeBridgingHeader && !outs.ModuleOutputPath.empty())
     serializationOpts.ImportedHeader = opts.ImplicitObjCHeaderPath;
   serializationOpts.ModuleLinkName = opts.ModuleLinkName;
+  serializationOpts.UserModuleVersion = opts.UserModuleVersion;
   serializationOpts.ExtraClangOptions = getClangImporterOptions().ExtraArgs;
 
   if (opts.EmitSymbolGraph) {

lib/Frontend/ModuleInterfaceBuilder.cpp

@@ -245,6 +245,7 @@ bool ModuleInterfaceBuilder::buildSwiftModuleInternal(
     SerializationOpts.ModuleLinkName = FEOpts.ModuleLinkName;
     SerializationOpts.AutolinkForceLoad =
       !subInvocation.getIRGenOptions().ForceLoadSymbolName.empty();
+    SerializationOpts.UserModuleVersion = FEOpts.UserModuleVersion;
 
     // Record any non-SDK module interface files for the debug info.
     StringRef SDKPath = SubInstance.getASTContext().SearchPathOpts.SDKPath;

lib/Serialization/ModuleFile.h

@@ -435,6 +435,10 @@ class ModuleFile
     return Core->ModuleABIName;
   }
 
+  llvm::VersionTuple getUserModuleVersion() const {
+    return Core->UserModuleVersion;
+  }
+
   /// The Swift compatibility version in use when this module was built.
   const version::Version &getCompatibilityVersion() const {
     return Core->CompatibilityVersion;

lib/Serialization/ModuleFileSharedCore.cpp

@@ -251,7 +251,12 @@ validateControlBlock(llvm::BitstreamCursor &cursor,
       // These fields were added later; be resilient against their absence.
       switch (scratch.size()) {
       default:
-        // Add new cases here, in descending order.
+      // Add new cases here, in descending order.
+      case 6:
+      case 5: {
+        result.userModuleVersion = llvm::VersionTuple(scratch[4], scratch[5]);
+        LLVM_FALLTHROUGH;
+      }
       case 4:
         if (scratch[3] != 0) {
           result.compatibilityVersion =
@@ -1172,6 +1177,7 @@ ModuleFileSharedCore::ModuleFileSharedCore(
       Name = info.name;
       TargetTriple = info.targetTriple;
       CompatibilityVersion = info.compatibilityVersion;
+      UserModuleVersion = info.userModuleVersion;
       Bits.ArePrivateImportsEnabled = extInfo.arePrivateImportsEnabled();
       Bits.IsSIB = extInfo.isSIB();
       Bits.IsTestable = extInfo.isTestable();

lib/Serialization/ModuleFileSharedCore.h

@@ -66,6 +66,9 @@ class ModuleFileSharedCore {
   /// The Swift compatibility version in use when this module was built.
   version::Version CompatibilityVersion;
 
+  /// User-defined module version number.
+  llvm::VersionTuple UserModuleVersion;
+
   /// The data blob containing all of the module's identifiers.
   StringRef IdentifierData;
 

lib/Serialization/ModuleFormat.h

@@ -56,7 +56,7 @@ const uint16_t SWIFTMODULE_VERSION_MAJOR = 0;
 /// describe what change you made. The content of this comment isn't important;
 /// it just ensures a conflict if two people change the module format.
 /// Don't worry about adhering to the 80-column limit for this line.
-const uint16_t SWIFTMODULE_VERSION_MINOR = 611; // implicit bit for CompletionHandlerAsyncAttr
+const uint16_t SWIFTMODULE_VERSION_MINOR = 612; // add user-defined module version
 
 /// A standard hash seed used for all string hashes in a serialized module.
 ///
@@ -763,6 +763,8 @@ namespace control_block {
     BCFixed<16>, // Module format minor version
     BCVBR<8>, // length of "short version string" in the blob
     BCVBR<8>, // length of "short compatibility version string" in the blob
+    BCVBR<17>, // User module format major version
+    BCVBR<17>, // User module format minor version
     BCBlob // misc. version information
   >;
 

lib/Serialization/Serialization.cpp

@@ -961,10 +961,16 @@ void Serializer::writeHeader(const SerializationOptions &options) {
     size_t compatibilityVersionStringLength =
         versionString.tell() - shortVersionStringLength - 1;
     versionString << ")/" << version::getSwiftFullVersion();
+    auto userModuleMajor = options.UserModuleVersion.getMajor();
+    auto userModuleMinor = 0;
+    if (auto minor = options.UserModuleVersion.getMinor()) {
+      userModuleMinor = *minor;
+    }
     Metadata.emit(ScratchRecord,
                   SWIFTMODULE_VERSION_MAJOR, SWIFTMODULE_VERSION_MINOR,
                   shortVersionStringLength,
                   compatibilityVersionStringLength,
+                  userModuleMajor, userModuleMinor,
                   versionString.str());
 
     Target.emit(ScratchRecord, M->getASTContext().LangOpts.Target.str());

lib/Serialization/SerializeDoc.cpp

@@ -489,10 +489,11 @@ void DocSerializer::writeDocHeader() {
     control_block::TargetLayout Target(Out);
 
     auto& LangOpts = M->getASTContext().LangOpts;
+    auto verText = version::getSwiftFullVersion(LangOpts.EffectiveLanguageVersion);
     Metadata.emit(ScratchRecord, SWIFTDOC_VERSION_MAJOR, SWIFTDOC_VERSION_MINOR,
                   /*short version string length*/0, /*compatibility length*/0,
-                  version::getSwiftFullVersion(
-                    LangOpts.EffectiveLanguageVersion));
+                  /*user module version major*/0,
+                  /*user module version minor*/0, verText);
 
     ModuleName.emit(ScratchRecord, M->getName().str());
     Target.emit(ScratchRecord, LangOpts.Target.str());
@@ -872,10 +873,12 @@ class SourceInfoSerializer : public SerializerBase {
       control_block::TargetLayout Target(Out);
 
       auto& LangOpts = M->getASTContext().LangOpts;
+      auto verText = version::getSwiftFullVersion(LangOpts.EffectiveLanguageVersion);
       Metadata.emit(ScratchRecord, SWIFTSOURCEINFO_VERSION_MAJOR,
                     SWIFTSOURCEINFO_VERSION_MINOR,
                     /*short version string length*/0, /*compatibility length*/0,
-              version::getSwiftFullVersion(LangOpts.EffectiveLanguageVersion));
+                    /*user module version major*/0,
+                    /*user module version minor*/0, verText);
 
       ModuleName.emit(ScratchRecord, M->getName().str());
       Target.emit(ScratchRecord, LangOpts.Target.str());

lib/Serialization/SerializedModuleLoader.cpp

@@ -725,7 +725,7 @@ LoadedFile *SerializedModuleLoaderBase::loadAST(
       M.setHasIncrementalInfo();
     if (!loadedModuleFile->getModuleABIName().empty())
       M.setABIName(Ctx.getIdentifier(loadedModuleFile->getModuleABIName()));
-
+    M.setUserModuleVersion(loadedModuleFile->getUserModuleVersion());
     auto diagLocOrInvalid = diagLoc.getValueOr(SourceLoc());
     loadInfo.status = loadedModuleFile->associateWithFileContext(
         fileUnit, diagLocOrInvalid, Ctx.LangOpts.AllowModuleWithCompilerErrors);

test/ModuleInterface/user-module-version.swift

@@ -0,0 +1,20 @@
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t/textual)
+// RUN: %empty-directory(%t/binary)
+// RUN: %empty-directory(%t/module-cache)
+
+// RUN: %target-swift-frontend -emit-module %s -module-name Foo -swift-version 5 -disable-implicit-concurrency-module-import -user-module-version 113.33 -emit-module-interface-path %t/textual/Foo.swiftinterface -enable-library-evolution -emit-module-path %t/binary/Foo.swiftmodule
+
+// RUN: %FileCheck %s --check-prefix=INTERFACE-FLAG < %t/textual/Foo.swiftinterface
+
+// RUN: %target-swift-ide-test -print-module-metadata -module-to-print Foo -I %t/textual -source-filename %s -module-cache-path %t/module-cache | %FileCheck %s --check-prefix=USER-MODULE-PRINT
+
+// RUN: %target-swift-ide-test -print-module-metadata -module-to-print Foo -I %t/binary -source-filename %s | %FileCheck %s --check-prefix=USER-MODULE-PRINT
+
+// RUN: rm %t/binary/Foo.swiftmodule
+// RUN: %target-swift-frontend -compile-module-from-interface %t/textual/Foo.swiftinterface -o %t/binary/Foo.swiftmodule
+// RUN: %target-swift-ide-test -print-module-metadata -module-to-print Foo -I %t/binary -source-filename %s | %FileCheck %s --check-prefix=USER-MODULE-PRINT
+
+// INTERFACE-FLAG: -user-module-version 113.33
+
+// USER-MODULE-PRINT: user module version: 113.33

tools/swift-ide-test/swift-ide-test.cpp

@@ -2515,6 +2515,7 @@ static int doPrintModuleGroups(const CompilerInvocation &InitInvok,
 
 static void printModuleMetadata(ModuleDecl *MD) {
   auto &OS = llvm::outs();
+  OS << "user module version: " << MD->getUserModuleVersion().getAsString() << "\n";
   OS << "fingerprint=" << MD->getFingerprint().getRawValue() << "\n";
   MD->collectLinkLibraries([&](LinkLibrary lib) {
     OS << "link library: " << lib.getName()