[IRGen] Use BC TI for resilient conformers.

Resilient types conforming to BitwiseCopyable mostly shouldn't go
through the VWT for value operations, they should just use memcpy.

Author: nate-chandler

lib/IRGen/GenEnum.cpp

@@ -7198,6 +7198,14 @@ ResilientEnumImplStrategy::completeEnumTypeLayout(TypeConverter &TC,
                                                   EnumDecl *theEnum,
                                                   llvm::StructType *enumTy) {
   auto abiAccessible = IsABIAccessible_t(TC.IGM.isTypeABIAccessible(Type));
+  auto *bitwiseCopyableProtocol =
+      IGM.getSwiftModule()->getASTContext().getProtocol(
+          KnownProtocolKind::BitwiseCopyable);
+  if (bitwiseCopyableProtocol &&
+      IGM.getSwiftModule()->lookupConformance(
+          theEnum->getDeclaredInterfaceType(), bitwiseCopyableProtocol)) {
+    return BitwiseCopyableTypeInfo::create(enumTy, abiAccessible);
+  }
   auto copyable = !theEnum->canBeCopyable()
     ? IsNotCopyable : IsCopyable;
   return registerEnumTypeInfo(

lib/IRGen/GenStruct.cpp

@@ -1690,6 +1690,14 @@ const TypeInfo *TypeConverter::convertStructType(TypeBase *key, CanType type,
       ? IsNotCopyable : IsCopyable;
     auto structAccessible =
       IsABIAccessible_t(IGM.getSILModule().isTypeMetadataAccessible(type));
+    auto *bitwiseCopyableProtocol =
+        IGM.getSwiftModule()->getASTContext().getProtocol(
+            KnownProtocolKind::BitwiseCopyable);
+    if (bitwiseCopyableProtocol &&
+        IGM.getSwiftModule()->lookupConformance(D->getDeclaredInterfaceType(),
+                                                bitwiseCopyableProtocol)) {
+      return BitwiseCopyableTypeInfo::create(IGM.OpaqueTy, structAccessible);
+    }
     return &getResilientStructTypeInfo(copyable, structAccessible);
   }
 

lib/IRGen/GenTuple.cpp

@@ -520,6 +520,13 @@ namespace {
 
 const TypeInfo *TypeConverter::convertTupleType(TupleType *tuple) {
   if (tuple->containsPackExpansionType()) {
+    auto *bitwiseCopyableProtocol =
+        IGM.getSwiftModule()->getASTContext().getProtocol(
+            KnownProtocolKind::BitwiseCopyable);
+    if (bitwiseCopyableProtocol && IGM.getSwiftModule()->lookupConformance(
+                                       tuple, bitwiseCopyableProtocol)) {
+      return BitwiseCopyableTypeInfo::create(IGM.OpaqueTy, IsABIAccessible);
+    }
     // FIXME: Figure out if its copyable at least
     return &getDynamicTupleTypeInfo(IsCopyable);
   }
@@ -696,4 +703,4 @@ llvm::Value *irgen::emitTupleTypeMetadataElementType(IRGenFunction &IGF,
 
   return IGF.Builder.CreateLoad(slot, IGF.IGM.SizeTy,
                                 IGF.IGM.getPointerAlignment());
-}
+}

lib/IRGen/NonFixedTypeInfo.h

@@ -136,14 +136,13 @@ class BitwiseCopyableTypeInfo
     : public WitnessSizedTypeInfo<BitwiseCopyableTypeInfo> {
   using Self = BitwiseCopyableTypeInfo;
   using Super = WitnessSizedTypeInfo<Self>;
-  BitwiseCopyableTypeInfo(llvm::Type *type,
-                                   IsABIAccessible_t abiAccessible)
+  BitwiseCopyableTypeInfo(llvm::Type *type, IsABIAccessible_t abiAccessible)
       : Super(type, Alignment(1), IsNotTriviallyDestroyable,
               IsNotBitwiseTakable, IsCopyable, abiAccessible) {}
 
 public:
-  static const BitwiseCopyableTypeInfo *
-  create(llvm::Type *type, IsABIAccessible_t abiAccessible) {
+  static BitwiseCopyableTypeInfo *create(llvm::Type *type,
+                                         IsABIAccessible_t abiAccessible) {
     return new Self(type, abiAccessible);
   }