Merge taskId and serialisableTaskId

A companion ghc-events pachakge commit displays task ids in the same format.

rts/Capability.c

@@ -417,9 +417,9 @@ giveCapabilityToTask (Capability *cap USED_IF_DEBUG, Task *task)
 {
     ASSERT_LOCK_HELD(&cap->lock);
     ASSERT(task->cap == cap);
-    debugTrace(DEBUG_sched, "passing capability %d to %s %p",
+    debugTrace(DEBUG_sched, "passing capability %d to %s %#" FMT_HexWord64,
                cap->no, task->incall->tso ? "bound task" : "worker",
-               (void *)(size_t)task->id);
+               serialisableTaskId(task));
     ACQUIRE_LOCK(&task->lock);
     if (task->wakeup == rtsFalse) {
         task->wakeup = rtsTrue;

rts/Task.c

@@ -395,22 +395,6 @@ workerTaskStop (Task *task)
 
 #endif
 
-#ifdef DEBUG
-// We don't replace this function with serialisableTaskId,
-// because debug prints as pointers are more readable than random
-// 64-bit intergers (especially on 32-bit architectures)
-// and because we want to use this function also for non-threaded RTS.
-static void *taskId(Task *task)
-{
-#ifdef THREADED_RTS
-    return (void *)(size_t)task->id;
-#else
-    return (void *)task;
-#endif
-}
-
-#endif
-
 #if defined(THREADED_RTS)
 
 static void OSThreadProcAttr
@@ -483,7 +467,8 @@ interruptWorkerTask (Task *task)
   ASSERT(osThreadId() != task->id);    // seppuku not allowed
   ASSERT(task->incall->suspended_tso); // use this only for FFI calls
   interruptOSThread(task->id);
-  debugTrace(DEBUG_sched, "interrupted worker task %p", taskId(task));
+  debugTrace(DEBUG_sched, "interrupted worker task %#" FMT_HexWord64,
+             serialisableTaskId(task));
 }
 
 #endif /* THREADED_RTS */
@@ -497,7 +482,8 @@ printAllTasks(void)
 {
     Task *task;
     for (task = all_tasks; task != NULL; task = task->all_next) {
-	debugBelch("task %p is %s, ", taskId(task), task->stopped ? "stopped" : "alive");
+	debugBelch("task %#" FMT_HexWord64 " is %s, ", serialisableTaskId(task),
+                   task->stopped ? "stopped" : "alive");
 	if (!task->stopped) {
 	    if (task->cap) {
 		debugBelch("on capability %d, ", task->cap->no);

rts/Task.h

@@ -312,7 +312,7 @@ serialisableTaskId (Task *task
 #if defined(THREADED_RTS)
     return serialiseTaskId(task->id);
 #else
-    return 1;
+    return (TaskId) (size_t) task;
 #endif
 }