Merge pull request #85551 from aschwaighofer/wip_embedded_exit

Preliminary support for existential in embedded Swift

include/swift/IRGen/Linking.h

@@ -89,11 +89,18 @@ enum class TypeMetadataAddress {
 inline bool isEmbedded(CanType t) {
   return t->getASTContext().LangOpts.hasFeature(Feature::Embedded);
 }
-
+inline bool isEmbeddedWithoutEmbeddedExitentials(CanType t) {
+  auto &langOpts = t->getASTContext().LangOpts;
+  return langOpts.hasFeature(Feature::Embedded) &&
+    !langOpts.hasFeature(Feature::EmbeddedExistentials);
+}
 // Metadata is not generated and not allowed to be referenced in Embedded Swift,
 // expect for classes (both generic and non-generic), dynamic self, and
 // class-bound existentials.
 inline bool isMetadataAllowedInEmbedded(CanType t) {
+  bool embeddedExistentials =
+    t->getASTContext().LangOpts.hasFeature(Feature::EmbeddedExistentials);
+
   if (isa<ClassType>(t) || isa<BoundGenericClassType>(t) ||
       isa<DynamicSelfType>(t)) {
     return true;
@@ -106,6 +113,9 @@ inline bool isMetadataAllowedInEmbedded(CanType t) {
     if (archeTy->requiresClass())
       return true;
   }
+
+  if (embeddedExistentials)
+    return true;
   return false;
 }
 
@@ -117,6 +127,11 @@ inline bool isEmbedded(const ProtocolConformance *c) {
   return c->getType()->getASTContext().LangOpts.hasFeature(Feature::Embedded);
 }
 
+inline bool isEmbeddedWithoutEmbeddedExitentials(const ProtocolConformance *c) {
+  return isEmbedded(c) && !c->getType()->getASTContext().
+    LangOpts.hasFeature(Feature::EmbeddedExistentials);
+}
+
 /// A link entity is some sort of named declaration, combined with all
 /// the information necessary to distinguish specific implementations
 /// of the declaration from each other.
@@ -1098,7 +1113,7 @@ public:
   }
 
   static LinkEntity forValueWitnessTable(CanType type) {
-    assert(!isEmbedded(type));
+    assert(!isEmbeddedWithoutEmbeddedExitentials(type));
     LinkEntity entity;
     entity.setForType(Kind::ValueWitnessTable, type);
     return entity;
@@ -1128,7 +1143,7 @@ public:
   }
 
   static LinkEntity forProtocolWitnessTable(const ProtocolConformance *C) {
-    if (isEmbedded(C)) {
+    if (isEmbeddedWithoutEmbeddedExitentials(C)) {
       assert(C->getProtocol()->requiresClass());
     }
 

include/swift/Runtime/RuntimeFunctions.def

@@ -236,6 +236,14 @@ FUNCTION(NativeStrongReleaseDirect, Swift, swift_releaseDirect, SwiftDirectRR_CC
          EFFECT(RuntimeEffect::RefCounting, RuntimeEffect::Deallocating),
          UNKNOWN_MEMEFFECTS)
 
+// void swift_releaseBox(void *ptr);
+FUNCTION(ReleaseBox, Swift, swift_releaseBox, C_CC, AlwaysAvailable,
+         RETURNS(VoidTy),
+         ARGS(RefCountedPtrTy),
+         ATTRS(NoUnwind),
+         EFFECT(RuntimeEffect::RefCounting, RuntimeEffect::Deallocating),
+         UNKNOWN_MEMEFFECTS)
+
 // void *swift_retain_n(void *ptr, int32_t n);
 FUNCTION(NativeStrongRetainN, Swift, swift_retain_n, C_CC, AlwaysAvailable,
          RETURNS(RefCountedPtrTy),