[AsyncLet] remove runChild; it is now asyncLetStart

Author: ktoso

include/swift/Runtime/RuntimeFunctions.def

@@ -1678,7 +1678,12 @@ FUNCTION(DefaultActorDeallocateResilient,
          ARGS(RefCountedPtrTy),
          ATTRS(NoUnwind))
 
-// THE RUNTIME FUNCTION
+/// void swift_asyncLet_start(
+///     AsyncLet *alet,
+///     const Metadata *futureResultType,
+///     void *closureEntryPoint,
+///     HeapObject *closureContext
+/// );
 FUNCTION(AsyncLetStart,
          swift_asyncLet_start, SwiftCC,
          ConcurrencyAvailability,

lib/SILGen/SILGen.cpp

@@ -354,13 +354,6 @@ static FuncDecl *lookupConcurrencyIntrinsic(ASTContext &C,
   return func;
 }
 
-FuncDecl *
-SILGenModule::getRunChildTask() {
-  return lookupConcurrencyIntrinsic(getASTContext(),
-                                    RunChildTask,
-                                    "_runChildTask");
-}
-
 FuncDecl *
 SILGenModule::getAsyncLetStart() {
   return lookupConcurrencyIntrinsic(getASTContext(),

lib/SILGen/SILGen.h

@@ -119,8 +119,6 @@ class LLVM_LIBRARY_VISIBILITY SILGenModule : public ASTVisitor<SILGenModule> {
 
   Optional<ProtocolConformance *> NSErrorConformanceToError;
 
-  Optional<FuncDecl*> RunChildTask;
-
   Optional<FuncDecl*> AsyncLetStart;
   Optional<FuncDecl*> AsyncLetGet;
   Optional<FuncDecl*> AsyncLetGetThrowing;
@@ -497,9 +495,6 @@ class LLVM_LIBRARY_VISIBILITY SILGenModule : public ASTVisitor<SILGenModule> {
   /// Retrieve the _Concurrency._asyncLetEnd intrinsic.
   FuncDecl *getEndAsyncLet();
 
-  /// Retrieve the _Concurrency._runChildTask intrinsic.
-  FuncDecl *getRunChildTask();
-
   /// Retrieve the _Concurrency._taskFutureGet intrinsic.
   FuncDecl *getTaskFutureGet();
 

lib/SILGen/SILGenApply.cpp

@@ -5793,32 +5793,6 @@ ManagedValue SILGenFunction::emitAsyncLetStart(
   return ManagedValue::forUnmanaged(apply);
 }
 
-ManagedValue SILGenFunction::emitRunChildTask(
-    SILLocation loc, Type functionType, ManagedValue taskFunction) {
-  auto runChildTaskFn = SGM.getRunChildTask();
-
-  Type resultType = functionType->castTo<FunctionType>()->getResult();
-  Type replacementTypes[] = {resultType};
-  auto subs = SubstitutionMap::get(runChildTaskFn->getGenericSignature(),
-                                   replacementTypes,
-                                   ArrayRef<ProtocolConformanceRef>{});
-
-  CanType origParamType = runChildTaskFn->getParameters()->get(0)
-      ->getInterfaceType()->getCanonicalType();
-  CanType substParamType = origParamType.subst(subs)->getCanonicalType();
-
-  // Ensure that the closure has the appropriate type.
-  AbstractionPattern origParam(
-      runChildTaskFn->getGenericSignature().getCanonicalSignature(),
-      origParamType);
-  taskFunction = emitSubstToOrigValue(
-      loc, taskFunction, origParam, substParamType);
-
-  return emitApplyOfLibraryIntrinsic(
-      loc, runChildTaskFn, subs, {taskFunction}, SGFContext()
-    ).getScalarValue();
-}
-
 ManagedValue SILGenFunction::emitCancelAsyncTask(
     SILLocation loc, SILValue task) {
   ASTContext &ctx = getASTContext();

lib/SILGen/SILGenFunction.h

@@ -1369,9 +1369,6 @@ class LLVM_LIBRARY_VISIBILITY SILGenFunction
                        ArgumentSource &&value,
                        bool isOnSelfParameter);
 
-  ManagedValue emitRunChildTask(
-      SILLocation loc, Type functionType, ManagedValue taskFunction);
-
   ManagedValue emitAsyncLetStart(
       SILLocation loc, Type functionType, ManagedValue taskFunction);
 

stdlib/public/Concurrency/Task.swift

@@ -724,37 +724,13 @@ public func _taskFutureGet<T>(_ task: Builtin.NativeObject) async -> T
 @_silgen_name("swift_task_future_wait_throwing")
 public func _taskFutureGetThrowing<T>(_ task: Builtin.NativeObject) async throws -> T
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
-public func _runChildTask<T>(
-  operation: @Sendable @escaping () async throws -> T
-) async -> Builtin.NativeObject {
-  assert(false);
-  let currentTask = Builtin.getCurrentAsyncTask()
-
-  // Set up the job flags for a new task.
-  var flags = Task.JobFlags()
-  flags.kind = .task
-  flags.priority = getJobFlags(currentTask).priority
-  flags.isFuture = true
-  flags.isChildTask = true
-
-  // Create the asynchronous task future.
-  let (task, _) = Builtin.createAsyncTaskFuture(flags.bits, operation)
-
-  // Enqueue the resulting job.
-  _enqueueJobGlobal(Builtin.convertTaskToJob(task))
-
-  return task
-}
-
 @available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
 @_silgen_name("swift_task_cancel")
 func _taskCancel(_ task: Builtin.NativeObject)
 
 @available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
 @_silgen_name("swift_task_isCancelled")
 func _taskIsCancelled(_ task: Builtin.NativeObject) -> Bool
-/// Attach child task to the parent (current) task.
 
 @available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
 @usableFromInline