SIL: Remove swift3ImplicitObjCEntrypoint built-in.

With the removal of `-enable-swift3-objc-inference`, no calls to the
`swift3ImplicitObjCEntrypoint` built-in should be generated anymore.

Author: tshortli

include/swift/AST/Builtins.def

@@ -764,9 +764,6 @@ BUILTIN_MISC_OPERATION(COWBufferForReading, "COWBufferForReading", "n", Special)
 // getObjCTypeEncoding has type <T> T.Type -> RawPointer
 BUILTIN_MISC_OPERATION(GetObjCTypeEncoding, "getObjCTypeEncoding", "n", Special)
 
-// Swift3ImplicitObjCEntrypoint has type () -> ()
-BUILTIN_MISC_OPERATION(Swift3ImplicitObjCEntrypoint, "swift3ImplicitObjCEntrypoint", "", Special)
-
 /// willThrow: Error -> ()
 BUILTIN_MISC_OPERATION(WillThrow, "willThrow", "", Special)
 

lib/AST/Builtins.cpp

@@ -2983,11 +2983,6 @@ ValueDecl *swift::getBuiltinValueDecl(ASTContext &Context, Identifier Id) {
   case BuiltinValueKind::TSanInoutAccess:
     return getTSanInoutAccess(Context, Id);
 
-  case BuiltinValueKind::Swift3ImplicitObjCEntrypoint:
-    return getBuiltinFunction(Id,
-                              {},
-                              TupleType::getEmpty(Context));
-
   case BuiltinValueKind::TypePtrAuthDiscriminator:
     return getTypePtrAuthDiscriminator(Context, Id);
 

lib/IRGen/GenBuiltin.cpp

@@ -1399,46 +1399,6 @@ void irgen::emitBuiltinCall(IRGenFunction &IGF, const BuiltinInfo &Builtin,
     out.add(result);
     return;
   }
-
-  if (Builtin.ID == BuiltinValueKind::Swift3ImplicitObjCEntrypoint) {
-    llvm::Value *entrypointArgs[7];
-    auto argIter = IGF.CurFn->arg_begin();
-
-    // self
-    entrypointArgs[0] = &*argIter++;
-    if (entrypointArgs[0]->getType() != IGF.IGM.ObjCPtrTy)
-      entrypointArgs[0] = IGF.Builder.CreateBitCast(entrypointArgs[0], IGF.IGM.ObjCPtrTy);
-
-    // _cmd
-    entrypointArgs[1] = &*argIter;
-    if (entrypointArgs[1]->getType() != IGF.IGM.ObjCSELTy)
-      entrypointArgs[1] = IGF.Builder.CreateBitCast(entrypointArgs[1], IGF.IGM.ObjCSELTy);
-    
-    // Filename pointer
-    entrypointArgs[2] = args.claimNext();
-    // Filename length
-    entrypointArgs[3] = args.claimNext();
-    // Line
-    entrypointArgs[4] = args.claimNext();
-    // Column
-    entrypointArgs[5] = args.claimNext();
-    
-    // Create a flag variable so that this invocation logs only once.
-    auto flagStorageTy = llvm::ArrayType::get(IGF.IGM.Int8Ty,
-                                        IGF.IGM.getAtomicBoolSize().getValue());
-    auto flag = new llvm::GlobalVariable(IGF.IGM.Module, flagStorageTy,
-                               /*constant*/ false,
-                               llvm::GlobalValue::PrivateLinkage,
-                               llvm::ConstantAggregateZero::get(flagStorageTy));
-    flag->setAlignment(
-        llvm::MaybeAlign(IGF.IGM.getAtomicBoolAlignment().getValue()));
-    entrypointArgs[6] = llvm::ConstantExpr::getBitCast(flag, IGF.IGM.Int8PtrTy);
-
-    IGF.Builder.CreateCall(
-        IGF.IGM.getSwift3ImplicitObjCEntrypointFunctionPointer(),
-        entrypointArgs);
-    return;
-  }
 
   if (Builtin.ID == BuiltinValueKind::TypePtrAuthDiscriminator) {
     (void)args.claimAll();

lib/SIL/IR/OperandOwnership.cpp

@@ -874,7 +874,6 @@ BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, GenericXor)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, ZExt)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, ZExtOrBitCast)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, ZeroInitializer)
-BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, Swift3ImplicitObjCEntrypoint)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, PoundAssert)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, GlobalStringTablePointer)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, TypePtrAuthDiscriminator)

lib/SIL/IR/ValueOwnership.cpp

@@ -581,7 +581,6 @@ CONSTANT_OWNERSHIP_BUILTIN(None, AtomicStore)
 CONSTANT_OWNERSHIP_BUILTIN(None, Once)
 CONSTANT_OWNERSHIP_BUILTIN(None, OnceWithContext)
 CONSTANT_OWNERSHIP_BUILTIN(None, TSanInoutAccess)
-CONSTANT_OWNERSHIP_BUILTIN(None, Swift3ImplicitObjCEntrypoint)
 CONSTANT_OWNERSHIP_BUILTIN(None, PoundAssert)
 CONSTANT_OWNERSHIP_BUILTIN(None, TypePtrAuthDiscriminator)
 CONSTANT_OWNERSHIP_BUILTIN(None, TargetOSVersionAtLeast)

lib/SIL/Utils/InstructionUtils.cpp

@@ -1008,8 +1008,6 @@ RuntimeEffect swift::getRuntimeEffect(SILInstruction *inst, SILType &impactType)
     case BuiltinValueKind::AssignCopyArrayBackToFront:
     case BuiltinValueKind::AssignTakeArray:
       return RuntimeEffect::RefCounting | RuntimeEffect::Deallocating;
-    case BuiltinValueKind::Swift3ImplicitObjCEntrypoint:
-      return RuntimeEffect::ObjectiveC | RuntimeEffect::Allocating;
     case BuiltinValueKind::BuildOrdinaryTaskExecutorRef:
     case BuiltinValueKind::BuildOrdinarySerialExecutorRef:
     case BuiltinValueKind::BuildComplexEqualitySerialExecutorRef:

lib/SIL/Utils/MemAccessUtils.cpp

@@ -2623,7 +2623,6 @@ static void visitBuiltinAddress(BuiltinInst *builtin,
     case BuiltinValueKind::Unreachable:
     case BuiltinValueKind::CondUnreachable:
     case BuiltinValueKind::DestroyArray:
-    case BuiltinValueKind::Swift3ImplicitObjCEntrypoint:
     case BuiltinValueKind::PoundAssert:
     case BuiltinValueKind::TSanInoutAccess:
     case BuiltinValueKind::CancelAsyncTask:

lib/SILOptimizer/Transforms/AccessEnforcementReleaseSinking.cpp

@@ -136,7 +136,6 @@ static bool isBarrier(SILInstruction *inst) {
     case BuiltinValueKind::Once:
     case BuiltinValueKind::OnceWithContext:
     case BuiltinValueKind::GetObjCTypeEncoding:
-    case BuiltinValueKind::Swift3ImplicitObjCEntrypoint:
     case BuiltinValueKind::WillThrow:
     case BuiltinValueKind::CondFailMessage:
     case BuiltinValueKind::PoundAssert: