[Concurrency] Remove C++ runtime references from embedded Concurrency.

In embedded mode, we mustn't have references to the C++ library, because
some embedded platforms don't include the C++ library.

Additionally, it's good to avoid use of global operator new and operator
delete, because they can be globally overridden and this has bitten us
in the past.

rdar://137286187

Author: al45tair

include/swift/Runtime/Heap.h

@@ -18,6 +18,7 @@
 #define SWIFT_RUNTIME_HEAP_H
 
 #include <cstddef>
+#include <limits>
 #include <new>
 #include <utility>
 
@@ -88,6 +89,86 @@ static inline void swift_cxx_deleteObject(T *ptr) {
     swift_slowDealloc(ptr, sizeof(T), alignof(T) - 1);
   }
 }
+
+/// Define a custom operator delete; this is useful when a class has a
+/// virtual destructor, as in that case the compiler will emit a deleting
+/// version of the destructor, which will call ::operator delete unless the
+/// class (or its superclasses) define one of their own.
+#define SWIFT_CXX_DELETE_OPERATOR(T)                    \
+  void operator delete(void *ptr) {                     \
+    swift_slowDealloc(ptr, sizeof(T), alignof(T) - 1);  \
+  }
+
+/// A C++ Allocator that uses the above functions instead of operator new
+/// and operator delete.  This lets us use STL containers without pulling
+/// in global operator new and global operator delete.
+template <typename T>
+struct cxx_allocator {
+  // Member types
+  typedef T              value_type;
+  typedef T             *pointer;
+  typedef const T       *const_pointer;
+  typedef T             &reference;
+  typedef const T       &const_reference;
+  typedef std::size_t    size_type;
+  typedef std::ptrdiff_t difference_type;
+  typedef std::true_type propagate_on_container_move_assignment;
+  typedef std::true_type is_always_equal;
+
+  template <typename U>
+  struct rebind {
+    typedef cxx_allocator<U> other;
+  };
+
+  pointer address(reference x) const noexcept {
+    return reinterpret_cast<pointer>(&reinterpret_cast<volatile char &>(x));
+  }
+
+  const_pointer address(const_reference x) const noexcept {
+    return reinterpret_cast<const_pointer>(&
+      reinterpret_cast<const volatile char &>(x));
+  }
+
+  T *allocate(std::size_t n) {
+    return reinterpret_cast<T *>(swift_slowAlloc(sizeof(T) * n,
+                                                 alignof(T) - 1));
+  }
+  T *allocate(std::size_t n, const void *hint) {
+    (void)hint;
+    return allocate(n);
+  }
+
+  void deallocate(T *p, std::size_t n) {
+    swift_slowDealloc(p, sizeof(T) * n, alignof(T) - 1);
+  }
+
+  size_type max_size() const noexcept {
+    return std::numeric_limits<size_type>::max() / sizeof(T);
+  }
+
+  template <class U, class... Args>
+  void construct(U *p, Args&&... args) {
+    ::new((void *)p) U(std::forward<Args>(args)...);
+  }
+
+  template <class U>
+  void destroy(U *p) {
+    p->~U();
+  }
+};
+
+template <typename T, typename U>
+bool operator==(const cxx_allocator<T> &lhs,
+                const cxx_allocator<U> &rhs) noexcept {
+  return true;
+}
+
+template <typename T, typename U>
+bool operator!=(const cxx_allocator<T> &lha,
+                const cxx_allocator<U> &rhs) noexcept {
+  return false;
+}
+
 }
 
 #endif // SWIFT_RUNTIME_HEAP_H

stdlib/public/Concurrency/Actor.cpp

@@ -32,6 +32,7 @@
 #include "swift/Runtime/Casting.h"
 #include "swift/Runtime/DispatchShims.h"
 #include "swift/Runtime/EnvironmentVariables.h"
+#include "swift/Runtime/Heap.h"
 #include "swift/Threading/Mutex.h"
 #include "swift/Threading/Once.h"
 #include "swift/Threading/Thread.h"
@@ -1325,7 +1326,7 @@ dispatch_lock_t *DefaultActorImpl::drainLockAddr() {
 
 void DefaultActorImpl::scheduleActorProcessJob(
     JobPriority priority, TaskExecutorRef taskExecutor) {
-  Job *job = new ProcessOutOfLineJob(this, priority);
+  Job *job = swift_cxx_newObject<ProcessOutOfLineJob>(this, priority);
   SWIFT_TASK_DEBUG_LOG(
       "Scheduling processing job %p for actor %p at priority %#zx, with taskExecutor %p", job, this,
       priority, taskExecutor.getIdentity());
@@ -1677,7 +1678,7 @@ void ProcessOutOfLineJob::process(Job *job) {
   auto self = cast<ProcessOutOfLineJob>(job);
   DefaultActorImpl *actor = self->Actor;
 
-  delete self;
+  swift_cxx_deleteObject(self);
   return defaultActorDrain(actor); // 'return' forces tail call
 }
 
@@ -2293,7 +2294,7 @@ class IsolatedDeinitJob : public Job {
     auto *job = cast<IsolatedDeinitJob>(_job);
     void *object = job->Object;
     DeinitWorkFunction *work = job->Work;
-    delete job;
+    swift_cxx_deleteObject(job);
     return work(object);
   }
 
@@ -2379,7 +2380,7 @@ static void swift_task_deinitOnExecutorImpl(void *object,
   auto priority = currentTask ? swift_task_currentPriority(currentTask)
                               : swift_task_getCurrentThreadPriority();
 
-  auto job = new IsolatedDeinitJob(priority, object, work);
+  auto job = swift_cxx_newObject<IsolatedDeinitJob>(priority, object, work);
   swift_task_enqueue(job, newExecutor);
 #endif
 }

stdlib/public/Concurrency/CooperativeGlobalExecutor.cpp

@@ -38,6 +38,7 @@
 
 #include <errno.h>
 #include "swift/Basic/PriorityQueue.h"
+#include "swift/Runtime/Heap.h"
 
 #if __has_include(<time.h>)
 # include <time.h>
@@ -103,10 +104,10 @@ struct JobDeadlineStorage<false> {
     return *storage(job);
   }
   static void set(SwiftJob *job, JobDeadline deadline) {
-    storage(job) = new JobDeadline(deadline);
+    storage(job) = swift_cxx_newObject<JobDeadline>(deadline);
   }
   static void destroy(SwiftJob *job) {
-    delete storage(job);
+    swift_cxx_deleteObject(storage(job));
   }
 };
 

stdlib/public/Concurrency/Task.cpp

@@ -34,6 +34,7 @@
 #include "swift/Runtime/Concurrency.h"
 #include "swift/Runtime/EnvironmentVariables.h"
 #include "swift/Runtime/HeapObject.h"
+#include "swift/Runtime/Heap.h"
 #include "swift/Threading/Mutex.h"
 #include <atomic>
 #include <new>
@@ -220,7 +221,7 @@ void NullaryContinuationJob::process(Job *_job) {
 
   auto *continuation = job->Continuation;
 
-  delete job;
+  swift_cxx_deleteObject(job);
 
   auto *context =
     static_cast<ContinuationAsyncContext*>(continuation->ResumeContext);
@@ -1718,7 +1719,7 @@ static NullaryContinuationJob*
 swift_task_createNullaryContinuationJobImpl(
     size_t priority,
     AsyncTask *continuation) {
-  auto *job = new NullaryContinuationJob(swift_task_getCurrent(),
+  auto *job = swift_cxx_newObject<NullaryContinuationJob>(swift_task_getCurrent(),
         static_cast<JobPriority>(priority), continuation);
 
   return job;

stdlib/public/Concurrency/TaskGroup.cpp

@@ -31,9 +31,11 @@
 #include "swift/Basic/STLExtras.h"
 #include "swift/Runtime/Concurrency.h"
 #include "swift/Runtime/Config.h"
+#include "swift/Runtime/Heap.h"
 #include "swift/Runtime/HeapObject.h"
 #include "swift/Threading/Mutex.h"
 #include <atomic>
+#include <deque>
 #include <new>
 
 #if SWIFT_STDLIB_HAS_ASL
@@ -114,7 +116,7 @@ class DiscardingTaskGroup;
 
 template<typename T>
 class NaiveTaskGroupQueue {
-  std::queue <T> queue;
+  std::queue<T, std::deque<T, swift::cxx_allocator<T>>> queue;
 
 public:
   NaiveTaskGroupQueue() = default;
@@ -346,6 +348,11 @@ class TaskGroupBase : public TaskGroupTaskStatusRecord {
 public:
   virtual ~TaskGroupBase() {}
 
+  /// Because we have a virtual destructor, we need to declare a delete operator
+  /// here, otherwise the compiler will generate a deleting destructor that
+  /// calls ::operator delete.
+  SWIFT_CXX_DELETE_OPERATOR(TaskGroupBase)
+
   TaskStatusRecordKind getKind() const {
     return Flags.getKind();
   }
@@ -419,7 +426,9 @@ class TaskGroupBase : public TaskGroupTaskStatusRecord {
   TaskGroupStatus statusLoadRelaxed() const;
   TaskGroupStatus statusLoadAcquire() const;
 
+#if !SWIFT_CONCURRENCY_EMBEDDED
   std::string statusString() const;
+#endif
 
   bool isEmpty() const;
 
@@ -469,6 +478,7 @@ class TaskGroupBase : public TaskGroupTaskStatusRecord {
 
 };
 
+#if !SWIFT_CONCURRENCY_EMBEDDED
 [[maybe_unused]]
 static std::string to_string(TaskGroupBase::PollStatus status) {
   switch (status) {
@@ -478,6 +488,7 @@ static std::string to_string(TaskGroupBase::PollStatus status) {
     case TaskGroupBase::PollStatus::Error: return "Error";
   }
 }
+#endif
 
 /// The status of a task group.
 ///
@@ -579,7 +590,13 @@ struct TaskGroupStatus {
     swift_asprintf(
         &message,
         "error: %sTaskGroup: detected pending task count overflow, in task group %p! Status: %s",
-        group->isDiscardingResults() ? "Discarding" : "", group, status.to_string(group).c_str());
+        group->isDiscardingResults() ? "Discarding" : "", group,
+#if !SWIFT_CONCURRENCY_EMBEDDED
+        status.to_string(group).c_str()
+#else
+        "<status unavailable in embedded>"
+#endif
+                   );
 
 #if !SWIFT_CONCURRENCY_EMBEDDED
     if (_swift_shouldReportFatalErrorsToDebugger()) {
@@ -612,6 +629,7 @@ struct TaskGroupStatus {
     abort();
   }
 
+#if !SWIFT_CONCURRENCY_EMBEDDED
   /// Pretty prints the status, as follows:
   /// If accumulating results:
   ///     TaskGroupStatus{ C:{cancelled} W:{waiting task} R:{ready tasks} P:{pending tasks} {binary repr} }
@@ -634,6 +652,7 @@ struct TaskGroupStatus {
     str.append(" }");
     return str;
   }
+#endif // !SWIFT_CONCURRENCY_EMBEDDED
 
   /// Initially there are no waiting and no pending tasks.
   static const TaskGroupStatus initial() {
@@ -691,9 +710,11 @@ TaskGroupStatus TaskGroupBase::statusLoadAcquire() const {
   return TaskGroupStatus{status.load(std::memory_order_acquire)};
 }
 
+#if !SWIFT_CONCURRENCY_EMBEDDED
 std::string TaskGroupBase::statusString() const {
   return statusLoadRelaxed().to_string(this);
 }
+#endif
 
 bool TaskGroupBase::isEmpty() const {
   auto oldStatus = TaskGroupStatus{status.load(std::memory_order_relaxed)};
@@ -749,6 +770,7 @@ TaskGroupStatus TaskGroupBase::statusAddPendingTaskAssumeRelaxed(bool unconditio
   }
 
   SWIFT_TASK_GROUP_DEBUG_LOG(this, "addPending, after: %s", s.to_string(this).c_str());
+
   return s;
 }
 
@@ -967,13 +989,13 @@ static void swift_taskGroup_initializeImpl(TaskGroup *group, const Metadata *T)
 SWIFT_CC(swift)
 static void swift_taskGroup_initializeWithFlagsImpl(size_t rawGroupFlags,
                                                     TaskGroup *group, const Metadata *T) {
-  ResultTypeInfo resultType;
 #if !SWIFT_CONCURRENCY_EMBEDDED
+  ResultTypeInfo resultType;
   resultType.metadata = T;
+  _swift_taskGroup_initialize(resultType, rawGroupFlags, group);
 #else
   swift_unreachable("swift_taskGroup_initializeWithFlags in embedded");
 #endif
-  _swift_taskGroup_initialize(resultType, rawGroupFlags, group);
 }
 
 // Initializes into the preallocated _group an actual instance.

stdlib/public/Concurrency/TaskLocal.cpp

@@ -19,6 +19,7 @@
 #include "swift/Runtime/Atomic.h"
 #include "swift/Runtime/Casting.h"
 #include "swift/Runtime/Concurrency.h"
+#include "swift/Runtime/Heap.h"
 #include "swift/Threading/ThreadLocalStorage.h"
 #include "llvm/ADT/PointerIntPair.h"
 #include <new>
@@ -473,7 +474,9 @@ void TaskLocal::Storage::copyTo(AsyncTask *target) {
   // because it is the most "specific"/"recent" binding and any other binding
   // of a key does not matter for the target task as it will never be able to
   // observe it.
-  std::set<const HeapObject*> copied = {};
+  std::set<const HeapObject *,
+           std::less<const HeapObject *>,
+           swift::cxx_allocator<const HeapObject *>> copied = {};
 
   auto item = head;
   while (item) {
@@ -499,7 +502,9 @@ void TaskLocal::Storage::copyToOnlyOnlyFromCurrentGroup(AsyncTask *target) {
   // because it is the most "specific"/"recent" binding and any other binding
   // of a key does not matter for the target task as it will never be able to
   // observe it.
-  std::set<const HeapObject*> copied = {};
+  std::set<const HeapObject *,
+           std::less<const HeapObject *>,
+           swift::cxx_allocator<const HeapObject *>> copied = {};
 
   auto item = head;
   TaskLocal::Item *copiedHead = nullptr;

test/embedded/dependencies-concurrency-custom-executor.swift

@@ -10,16 +10,6 @@
 // Fail if there is any entry in actual-dependencies.txt that's not in allowed-dependencies.txt
 // RUN: test -z "`comm -13 %t/allowed-dependencies.txt %t/actual-dependencies.txt`"
 
-// DEP: __ZNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEE6appendEPKc
-// DEP: __ZNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEE6appendEPKcm
-// DEP: __ZNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEE6insertEmPKc
-// DEP: __ZNSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEED1Ev
-// DEP: __ZNSt3__16chrono12steady_clock3nowEv
-// DEP: __ZNSt3__19to_stringEj
-// DEP: __ZNSt3__19to_stringEy
-// DEP: __ZdlPv
-// DEP: __ZdlPvm
-// DEP: __Znwm
 // DEP: ___assert_rtn
 // DEP: ___error
 // DEP: ___stack_chk_fail