[move-only] Do not attempt to lazily deserialize the moveonly deinit table in IRGen.

The reason to avoid this is if we attempt to lazily deserialize the moveonly
deinit table, we may also attempt to deserialize a deinit function. This would
result in us breaking the invariant that we no longer deserialize SILFunctions
once we are in LoweredSIL.

If we fail to lazily deserialize, we instead just call the deinit via the
destroy value witness of the type.

This only affects builds built with asserts enabled since llvm_unreachable is
compiled out when NDEBUG is set.

rdar://110496872

Author: gottesmm

lib/IRGen/GenType.cpp

@@ -2897,9 +2897,11 @@ static bool tryEmitDeinitCall(IRGenFunction &IGF,
     return false;
   }
 
-  auto deinitTable = IGF.getSILModule().lookUpMoveOnlyDeinit(nominal);
+  auto deinitTable = IGF.getSILModule().lookUpMoveOnlyDeinit(
+      nominal, false /*deserialize lazily*/);
 
-  // If we do not have a deinit table, call the value witness instead.
+  // If we do not have a deinit table already deserialized, call the value
+  // witness instead.
   if (!deinitTable) {
     irgen::emitDestroyCall(IGF, T, indirect());
     indirectCleanup();

test/Interpreter/Inputs/moveonly_split_module_source_input.swift

@@ -1,19 +1,35 @@
 
-#if TEST_LIBRARY_EVOLUTION
+#if TEST_LIBRARY_WITH_LIBRARY_EVOLUTION
 public struct MoveOnly : ~Copyable {
     var name = "John"
     public init() {}
     deinit {
-        print("==> I am in the deinit resiliently!")
+        print("==> LIBRARY_EVOLUTION: I am in the deinit!")
         print("==> My name is: \(name)!")
     }
 }
 #else
+
+#if TEST_LIBRARY_WITHOUT_LIBRARY_EVOLUTION
+
+public class MoveOnly {
+    var name = "John"
+    public init() {}
+    deinit {
+        print("==> LIBRARY: I am in the deinit!")
+        print("==> My name is: \(name)!")
+    }
+}
+
+#else
+
 struct MoveOnly : ~Copyable {
     var name = "John"
     deinit {
         print("==> I am in the deinit!")
         print("==> My name is: \(name)!")
     }
 }
+
+#endif
 #endif

test/Interpreter/moveonly_deinit_separate_library.swift

@@ -0,0 +1,19 @@
+// RUN: %empty-directory(%t/normal)
+// RUN: %target-build-swift-dylib(%t/normal/%target-library-name(MoveOnlySplit)) %S/Inputs/moveonly_split_module_source_input.swift -emit-module -emit-module-path %t/normal/MoveOnlySplit.swiftmodule -module-name MoveOnlySplit -DTEST_LIBRARY_WITHOUT_LIBRARY_EVOLUTION
+// RUN: %target-codesign %t/normal/%target-library-name(MoveOnlySplit)
+
+// RUN: %target-build-swift %s -lMoveOnlySplit -I %t/normal -L %t/normal -o %t/normal/main %target-rpath(%t/normal)
+// RUN: %target-codesign %t/normal/main
+// RUN: %target-run %t/normal/main %t/normal/%target-library-name(MoveOnlySplit) | %FileCheck %s
+
+// REQUIRES: executable_test
+
+import MoveOnlySplit
+
+func main() {
+    // CHECK: ==> LIBRARY: I am in the deinit!
+    // CHECK-LIBRARY-EVOLUTION: ==> LIBRARY_EVOLUTION: I am in the deinit!
+    let server = MoveOnly()
+}
+
+main()