Serialize/deserialize lifetime dependencies on enum elements

Author: meg-gupta

lib/Serialization/Deserialization.cpp

@@ -5259,6 +5259,16 @@ class DeclDeserializer {
     elem->setAccess(std::max(cast<EnumDecl>(DC)->getFormalAccess(),
                              AccessLevel::Internal));
 
+    SmallVector<LifetimeDependenceInfo, 1> lifetimeDependencies;
+    while (auto info = MF.maybeReadLifetimeDependence()) {
+      assert(info.has_value());
+      lifetimeDependencies.push_back(*info);
+    }
+
+    ctx.evaluator.cacheOutput(LifetimeDependenceInfoRequest{elem},
+                              lifetimeDependencies.empty()? std::nullopt :
+                                  ctx.AllocateCopy(lifetimeDependencies));
+
     return elem;
   }
 

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 = 954; // Checked cast inst options
+const uint16_t SWIFTMODULE_VERSION_MINOR = 955; // Lifetime dependencies on enum element
 
 /// A standard hash seed used for all string hashes in a serialized module.
 ///

lib/Serialization/Serialization.cpp

@@ -5021,6 +5021,14 @@ class Serializer::DeclSerializer : public DeclVisitor<DeclSerializer> {
                                   nameComponentsAndDependencies);
     if (auto *PL = elem->getParameterList())
       writeParameterList(PL);
+
+    auto fnType = ty->getAs<AnyFunctionType>();
+    if (fnType) {
+      auto lifetimeDependencies = fnType->getLifetimeDependencies();
+      if (!lifetimeDependencies.empty()) {
+        S.writeLifetimeDependencies(lifetimeDependencies);
+      }
+    }
   }
 
   void visitSubscriptDecl(const SubscriptDecl *subscript) {