Merge pull request #29710 from CodaFi/cereal-is-a-soup-change-my-mind

[ModuleInterface] Pass Through Flags for Nested Types Tables

Author: CodaFi

lib/Frontend/ModuleInterfaceBuilder.cpp

@@ -347,6 +347,8 @@ bool ModuleInterfaceBuilder::buildSwiftModuleInternal(
     // optimization pipeline.
     SerializationOptions SerializationOpts;
     std::string OutPathStr = OutPath;
+    SerializationOpts.EnableNestedTypeLookupTable
+        = FEOpts.EnableSerializationNestedTypeLookupTable;
     SerializationOpts.OutputPath = OutPathStr.c_str();
     SerializationOpts.ModuleLinkName = FEOpts.ModuleLinkName;
     SerializationOpts.AutolinkForceLoad =

lib/Serialization/ModuleFormat.h

@@ -55,7 +55,7 @@ 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 = 537; // SIL differentiability witnesses
+const uint16_t SWIFTMODULE_VERSION_MINOR = 538; // swiftmodules from swiftinterfaces have nested types tables
 
 /// A standard hash seed used for all string hashes in a serialized module.
 ///

test/Serialization/interface-module-nested-types.swift

@@ -0,0 +1,35 @@
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t/ModuleCache)
+// RUN: %empty-directory(%t/Build)
+// RUN: %empty-directory(%t/PrebuiltCache)
+
+// 1. Create a module for our nested type
+// RUN: echo 'public protocol Nest { associatedtype Egg }' > %t/TestModule.swift
+
+// 2. Create an interface for it
+// RUN: %target-swift-frontend -typecheck %t/TestModule.swift -emit-module-interface-path %t/Build/TestModule.swiftinterface -swift-version 5
+
+// 3. Build a .swiftmodule from the .swiftinterface and put it in the module cache
+// RUN: %target-swift-frontend -compile-module-from-interface %t/Build/TestModule.swiftinterface -o %t/PrebuiltCache/TestModule.swiftmodule
+
+// 4. Import the module in a different module that extends the nested type.
+// RUN: echo 'import TestModule; extension Nest where Egg == Int { public func robin() -> Egg { return 3 } }' > %t/NestModule.swift
+
+// 5. Create an interface for it
+// RUN: %target-swift-frontend -typecheck %t/NestModule.swift -I %t/PrebuiltCache -sdk %t -prebuilt-module-cache-path %t/PrebuiltCache -module-cache-path %t/ModuleCache -emit-module-interface-path %t/Build/NestModule.swiftinterface -swift-version 5
+
+// 6. Build a .swiftmodule from the .swiftinterface and put it in the module cache
+// RUN: %target-swift-frontend -compile-module-from-interface -I %t/PrebuiltCache -sdk %t %t/Build/NestModule.swiftinterface -o %t/PrebuiltCache/NestModule.swiftmodule
+
+// 7. Ensure we resolve the cross-ref to the nested type properly.
+// RUN: %target-swift-frontend -typecheck %s -I %t/PrebuiltCache -sdk %t -prebuilt-module-cache-path %t/PrebuiltCache -module-cache-path %t/ModuleCache -print-stats 2>&1 | %FileCheck %s
+
+import TestModule
+import NestModule
+
+// CHECK: Statistics
+// CHECK: 1 Serialization - # of nested types resolved without full lookup
+
+func tweet<Location: Nest>(from place: Location) where Location.Egg == Int {
+  _ = place.robin()
+}