[SIL] Add a new attribute [serialized_for_package].

If Package CMO is enabled, we now add a new attribute to
a serialized function, which can then be used during
deserialization into a client module to determine the
resilience expansion of the function.

Resolves rdar://127870822

include/swift/SIL/SILFunction.h

@@ -363,6 +363,10 @@ class SILFunction
   /// The function's serialized attribute.
   bool Serialized : 1;
 
+  /// [serialized_for_package] attribute if package serialization
+  /// is enabled.
+  bool SerializedForPackage : 1;
+
   /// Specifies if this function is a thunk or a reabstraction thunk.
   ///
   /// The inliner uses this information to avoid inlining (non-trivial)
@@ -1138,6 +1142,13 @@ class SILFunction
            "too few bits for Serialized storage");
   }
 
+  IsSerializedForPackage_t isSerializedForPackage() const {
+    return IsSerializedForPackage_t(SerializedForPackage);
+  }
+  void setSerializedForPackage(IsSerializedForPackage_t isSerializedForPackage) {
+    SerializedForPackage = isSerializedForPackage;
+  }
+
   /// Get this function's thunk attribute.
   IsThunk_t isThunk() const { return IsThunk_t(Thunk); }
   void setThunk(IsThunk_t isThunk) {

include/swift/SIL/SILLinkage.h

@@ -162,6 +162,11 @@ enum IsSerialized_t : unsigned char {
   IsSerialized
 };
 
+enum IsSerializedForPackage_t : unsigned char {
+  IsNotSerializedForPackage,
+  IsSerializedForPackage
+};
+
 /// The scope in which a subclassable class can be subclassed.
 enum class SubclassScope : uint8_t {
   /// This class can be subclassed in other modules.

lib/SIL/IR/SILFunction.cpp

@@ -523,12 +523,22 @@ ResilienceExpansion SILFunction::getResilienceExpansion() const {
   // source and is never used outside of its package;
   // Even if the module is built resiliently, return
   // maximal expansion here so aggregate types can be
-  // loadable in the same resilient domain (from a client
-  // module in the same package.
+  // treated as loadable in the same resilient domain
+  // (across modules in the same package).
   if (getModule().getSwiftModule()->serializePackageEnabled() &&
       getModule().getSwiftModule()->isResilient())
     return ResilienceExpansion::Maximal;
 
+  // If a function definition is in another module, and
+  // it was serialized due to package serialization opt,
+  // a new attribute [serialized_for_package] is added
+  // to the definition site. During deserialization, this
+  // attribute is preserved if the current module is in
+  // the same package, thus should be in the same resilience
+  // domain.
+  if (isSerializedForPackage() == IsSerializedForPackage)
+    return ResilienceExpansion::Maximal;
+
   return (isSerialized()
           ? ResilienceExpansion::Minimal
           : ResilienceExpansion::Maximal);

lib/SIL/IR/SILPrinter.cpp

@@ -3341,6 +3341,11 @@ void SILFunction::print(SILPrintContext &PrintCtx) const {
   case IsSerialized: OS << "[serialized] "; break;
   }
 
+  switch (isSerializedForPackage()) {
+  case IsNotSerializedForPackage: break;
+  case IsSerializedForPackage: OS << "[serialized_for_package] "; break;
+  }
+
   switch (isThunk()) {
   case IsNotThunk: break;
   case IsThunk: OS << "[thunk] "; break;
@@ -3528,7 +3533,7 @@ void SILGlobalVariable::print(llvm::raw_ostream &OS, bool Verbose) const {
 
   if (isSerialized())
     OS << "[serialized] ";
-  
+
   if (isLet())
     OS << "[let] ";
 
@@ -3840,7 +3845,7 @@ void SILProperty::print(SILPrintContext &Ctx) const {
   OS << "sil_property ";
   if (isSerialized())
     OS << "[serialized] ";
-  
+
   OS << '#';
   printValueDecl(getDecl(), OS);
   if (auto sig = getDecl()->getInnermostDeclContext()
@@ -4019,6 +4024,7 @@ void SILVTable::print(llvm::raw_ostream &OS, bool Verbose) const {
   OS << "sil_vtable ";
   if (isSerialized())
     OS << "[serialized] ";
+
   if (SILType classTy = getClassType()) {
     OS << classTy;
   } else {

lib/SIL/Parser/ParseSIL.cpp

@@ -665,7 +665,8 @@ void SILParser::convertRequirements(ArrayRef<RequirementRepr> From,
 }
 
 static bool parseDeclSILOptional(
-    bool *isTransparent, IsSerialized_t *isSerialized, bool *isCanonical,
+    bool *isTransparent, IsSerialized_t *isSerialized,
+    IsSerializedForPackage_t *isSerializedForPackage, bool *isCanonical,
     bool *hasOwnershipSSA, bool *hasResultDependsOnSelf, IsThunk_t *isThunk,
     IsDynamicallyReplaceable_t *isDynamic, IsDistributed_t *isDistributed,
     IsRuntimeAccessible_t *isRuntimeAccessible,
@@ -697,6 +698,8 @@ static bool parseDeclSILOptional(
       *isTransparent = true;
     else if (isSerialized && SP.P.Tok.getText() == "serialized")
       *isSerialized = IsSerialized;
+    else if (isSerializedForPackage && SP.P.Tok.getText() == "serialized_for_package")
+      *isSerializedForPackage = IsSerializedForPackage;
     else if (isDynamic && SP.P.Tok.getText() == "dynamically_replacable")
       *isDynamic = IsDynamic;
     else if (isDistributed && SP.P.Tok.getText() == "distributed")
@@ -7106,6 +7109,7 @@ bool SILParserState::parseDeclSIL(Parser &P) {
 
   bool isTransparent = false;
   IsSerialized_t isSerialized = IsNotSerialized;
+  IsSerializedForPackage_t isSerializedForPackage = IsNotSerializedForPackage;
   bool isCanonical = false;
   IsDynamicallyReplaceable_t isDynamic = IsNotDynamic;
   IsDistributed_t isDistributed = IsNotDistributed;
@@ -7138,8 +7142,9 @@ bool SILParserState::parseDeclSIL(Parser &P) {
   Identifier objCReplacementFor;
   if (parseSILLinkage(FnLinkage, P) ||
       parseDeclSILOptional(
-          &isTransparent, &isSerialized, &isCanonical, &hasOwnershipSSA,
-          &hasResultDependsOnSelf, &isThunk, &isDynamic, &isDistributed,
+          &isTransparent, &isSerialized, &isSerializedForPackage,
+          &isCanonical, &hasOwnershipSSA, &hasResultDependsOnSelf,
+          &isThunk, &isDynamic, &isDistributed,
           &isRuntimeAccessible, &forceEnableLexicalLifetimes,
           &useStackForPackMetadata, &hasUnsafeNonEscapableResult,
           &isExactSelfClass, &DynamicallyReplacedFunction,
@@ -7173,6 +7178,7 @@ bool SILParserState::parseDeclSIL(Parser &P) {
     FunctionState.F->setBare(IsBare);
     FunctionState.F->setTransparent(IsTransparent_t(isTransparent));
     FunctionState.F->setSerialized(IsSerialized_t(isSerialized));
+    FunctionState.F->setSerializedForPackage(IsSerializedForPackage_t(isSerializedForPackage));
     FunctionState.F->setWasDeserializedCanonical(isCanonical);
     if (!hasOwnershipSSA)
       FunctionState.F->setOwnershipEliminated();
@@ -7396,13 +7402,12 @@ bool SILParserState::parseSILGlobal(Parser &P) {
 
   SILParser State(P);
   if (parseSILLinkage(GlobalLinkage, P) ||
-      parseDeclSILOptional(nullptr, &isSerialized, nullptr, nullptr, nullptr,
+      parseDeclSILOptional(nullptr, &isSerialized, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
-                           nullptr,
-                           nullptr, nullptr, nullptr, nullptr, nullptr, &isLet,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
-                           nullptr, nullptr, State, M) ||
+                           &isLet, nullptr, nullptr, nullptr, nullptr, nullptr,
+                           nullptr, nullptr, nullptr, State, M) ||
       P.parseToken(tok::at_sign, diag::expected_sil_value_name) ||
       P.parseIdentifier(GlobalName, NameLoc, /*diagnoseDollarPrefix=*/false,
                         diag::expected_sil_value_name) ||
@@ -7449,12 +7454,13 @@ bool SILParserState::parseSILProperty(Parser &P) {
   SILParser SP(P);
 
   IsSerialized_t Serialized = IsNotSerialized;
-  if (parseDeclSILOptional(nullptr, &Serialized, nullptr, nullptr, nullptr,
+  if (parseDeclSILOptional(nullptr, &Serialized, nullptr, nullptr,
+                           nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
-                           nullptr, nullptr, nullptr, SP, M))
+                           SP, M))
     return true;
 
   ValueDecl *VD;
@@ -7524,7 +7530,7 @@ bool SILParserState::parseSILVTable(Parser &P) {
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
-                           nullptr, nullptr, nullptr, VTableState, M))
+                           nullptr, nullptr, nullptr, nullptr, VTableState, M))
     return true;
 
 
@@ -7642,7 +7648,7 @@ bool SILParserState::parseSILMoveOnlyDeinit(Parser &parser) {
   SILParser moveOnlyDeinitTableState(parser);
 
   IsSerialized_t Serialized = IsNotSerialized;
-  if (parseDeclSILOptional(nullptr, &Serialized, nullptr, nullptr, nullptr,
+  if (parseDeclSILOptional(nullptr, &Serialized, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
@@ -8129,7 +8135,7 @@ bool SILParserState::parseSILWitnessTable(Parser &P) {
   parseSILLinkage(Linkage, P);
 
   IsSerialized_t isSerialized = IsNotSerialized;
-  if (parseDeclSILOptional(nullptr, &isSerialized, nullptr, nullptr, nullptr,
+  if (parseDeclSILOptional(nullptr, &isSerialized, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
                            nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,

lib/SILOptimizer/IPO/CrossModuleOptimization.cpp

@@ -571,17 +571,25 @@ bool CrossModuleOptimization::shouldSerialize(SILFunction *function) {
   return true;
 }
 
+static void addSerializedForPackageAttrIfEnabled(SILFunction *f, const SILModule &mod) {
+  auto packageOptIn = mod.getOptions().EnableSerializePackage &&
+                      mod.getSwiftModule()->isResilient();
+  f->setSerializedForPackage(packageOptIn ? IsSerializedForPackage : IsNotSerializedForPackage);
+}
+
 /// Serialize \p function and recursively all referenced functions which are
 /// marked in \p canSerializeFlags.
 void CrossModuleOptimization::serializeFunction(SILFunction *function,
                                        const FunctionFlags &canSerializeFlags) {
-  if (function->isSerialized())
+  if (function->isSerialized()) {
+    addSerializedForPackageAttrIfEnabled(function, M);
     return;
-
+  }
   if (!canSerializeFlags.lookup(function))
     return;
 
   function->setSerialized(IsSerialized);
+  addSerializedForPackageAttrIfEnabled(function, M);
 
   for (SILBasicBlock &block : *function) {
     for (SILInstruction &inst : block) {

lib/Serialization/DeserializeSIL.cpp

@@ -563,16 +563,16 @@ SILDeserializer::readSILFunctionChecked(DeclID FID, SILFunction *existingFn,
   IdentifierID replacedFunctionID;
   IdentifierID usedAdHocWitnessFunctionID;
   GenericSignatureID genericSigID;
-  unsigned rawLinkage, isTransparent, isSerialized, isThunk,
-      isWithoutActuallyEscapingThunk, specialPurpose, inlineStrategy,
+  unsigned rawLinkage, isTransparent, isSerialized, isSerializedForPackage,
+      isThunk, isWithoutActuallyEscapingThunk, specialPurpose, inlineStrategy,
       optimizationMode, perfConstr, subclassScope, hasCReferences, effect,
       numAttrs, hasQualifiedOwnership, isWeakImported,
       LIST_VER_TUPLE_PIECES(available), isDynamic, isExactSelfClass,
       isDistributed, isRuntimeAccessible, forceEnableLexicalLifetimes;
   ArrayRef<uint64_t> SemanticsIDs;
   SILFunctionLayout::readRecord(
-      scratch, rawLinkage, isTransparent, isSerialized, isThunk,
-      isWithoutActuallyEscapingThunk, specialPurpose, inlineStrategy,
+      scratch, rawLinkage, isTransparent, isSerialized, isSerializedForPackage,
+      isThunk, isWithoutActuallyEscapingThunk, specialPurpose, inlineStrategy,
       optimizationMode, perfConstr, subclassScope, hasCReferences, effect,
       numAttrs, hasQualifiedOwnership, isWeakImported,
       LIST_VER_TUPLE_PIECES(available), isDynamic, isExactSelfClass,
@@ -656,13 +656,26 @@ SILDeserializer::readSILFunctionChecked(DeclID FID, SILFunction *existingFn,
 
     fn->setSerialized(IsSerialized_t(isSerialized));
 
+    // If fn was serialized in a module with package serialization
+    // enabled, a new attribute [serialized_for_package] was added
+    // to its definition. Preserve the attribute here if the current
+    // module is in the same package, and use it to determine the
+    // resilience expansion for this function.
+    auto loadedModule = getFile()->getParentModule();
+    if (isSerializedForPackage == IsSerializedForPackage &&
+        loadedModule->isResilient() &&
+        loadedModule != SILMod.getSwiftModule() &&
+        loadedModule->serializePackageEnabled() &&
+        loadedModule->inSamePackage(SILMod.getSwiftModule()))
+      fn->setSerializedForPackage(IsSerializedForPackage);
+
     // If the serialized function comes from the same module, we're merging
     // modules, and can update the linkage directly. This is needed to
     // correctly update the linkage for forward declarations to entities defined
     // in another file of the same module – we want to ensure the linkage
     // reflects the fact that the entity isn't really external and shouldn't be
     // dropped from the resulting merged module.
-    if (getFile()->getParentModule() == SILMod.getSwiftModule())
+    if (loadedModule == SILMod.getSwiftModule())
       fn->setLinkage(linkage);
 
     // Don't override the transparency or linkage of a function with
@@ -703,6 +716,7 @@ SILDeserializer::readSILFunctionChecked(DeclID FID, SILFunction *existingFn,
     fn->setLinkage(linkage);
     fn->setTransparent(IsTransparent_t(isTransparent == 1));
     fn->setSerialized(IsSerialized_t(isSerialized));
+    fn->setSerializedForPackage(IsSerializedForPackage_t(isSerializedForPackage));
     fn->setThunk(IsThunk_t(isThunk));
     fn->setWithoutActuallyEscapingThunk(bool(isWithoutActuallyEscapingThunk));
     fn->setInlineStrategy(Inline_t(inlineStrategy));
@@ -3520,16 +3534,16 @@ bool SILDeserializer::hasSILFunction(StringRef Name,
   IdentifierID replacedFunctionID;
   IdentifierID usedAdHocWitnessFunctionID;
   GenericSignatureID genericSigID;
-  unsigned rawLinkage, isTransparent, isSerialized, isThunk,
-      isWithoutActuallyEscapingThunk, isGlobal, inlineStrategy,
+  unsigned rawLinkage, isTransparent, isSerialized, isSerializedForPackage,
+      isThunk, isWithoutActuallyEscapingThunk, isGlobal, inlineStrategy,
       optimizationMode, perfConstr, subclassScope, hasCReferences, effect,
       numSpecAttrs, hasQualifiedOwnership, isWeakImported,
       LIST_VER_TUPLE_PIECES(available), isDynamic, isExactSelfClass,
       isDistributed, isRuntimeAccessible, forceEnableLexicalLifetimes;
   ArrayRef<uint64_t> SemanticsIDs;
   SILFunctionLayout::readRecord(
-      scratch, rawLinkage, isTransparent, isSerialized, isThunk,
-      isWithoutActuallyEscapingThunk, isGlobal, inlineStrategy,
+      scratch, rawLinkage, isTransparent, isSerialized, isSerializedForPackage,
+      isThunk, isWithoutActuallyEscapingThunk, isGlobal, inlineStrategy,
       optimizationMode, perfConstr, subclassScope, hasCReferences, effect,
       numSpecAttrs, hasQualifiedOwnership, isWeakImported,
       LIST_VER_TUPLE_PIECES(available), isDynamic, isExactSelfClass,
@@ -3981,7 +3995,7 @@ SILProperty *SILDeserializer::readProperty(DeclID PId) {
   DeclID StorageID;
   ArrayRef<uint64_t> ComponentValues;
   PropertyLayout::readRecord(scratch, StorageID, Serialized, ComponentValues);
-  
+
   auto decl = cast<AbstractStorageDecl>(MF->getDecl(StorageID));
   unsigned ComponentValueIndex = 0;
   auto component = readKeyPathComponent(ComponentValues, ComponentValueIndex);

lib/Serialization/ModuleFormat.h

@@ -58,7 +58,7 @@ 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 = 872; // SerializePackageEnabled
+const uint16_t SWIFTMODULE_VERSION_MINOR = 873; // [serialized_for_package] for SILFunctionLayout
 
 /// A standard hash seed used for all string hashes in a serialized module.
 ///

lib/Serialization/SILFormat.h

@@ -292,6 +292,7 @@ namespace sil_block {
       BCRecordLayout<SIL_FUNCTION, SILLinkageField,
                      BCFixed<1>,  // transparent
                      BCFixed<1>,  // serialized
+                     BCFixed<1>,  // serializedForPackage
                      BCFixed<2>,  // thunks: signature optimized/reabstraction
                      BCFixed<1>,  // without_actually_escaping
                      BCFixed<3>,  // specialPurpose

lib/Serialization/SerializeSIL.cpp

@@ -512,6 +512,7 @@ void SILSerializer::writeSILFunction(const SILFunction &F, bool DeclOnly) {
   SILFunctionLayout::emitRecord(
       Out, ScratchRecord, abbrCode, toStableSILLinkage(Linkage),
       (unsigned)F.isTransparent(), (unsigned)F.isSerialized(),
+      (unsigned)F.isSerializedForPackage(),
       (unsigned)F.isThunk(), (unsigned)F.isWithoutActuallyEscapingThunk(),
       (unsigned)F.getSpecialPurpose(), (unsigned)F.getInlineStrategy(),
       (unsigned)F.getOptimizationMode(), (unsigned)F.getPerfConstraints(),