Add new shared pointer and make use of it

arm9/source/core/AtomicSharedPtr.cpp

@@ -0,0 +1,35 @@
+#include "common.h"
+#include <libtwl/rtos/rtosIrq.h>
+#include "AtomicSharedPtr.h"
+
+void AtomicSharedPtrBase::Reset(void* newObject, RefCount* newRefCount, bool increaseNewRefCount)
+{
+    u32 irq = rtos_disableIrqs(); // 1
+    auto refCount = _refCount;
+    _object = newObject;
+    _refCount = newRefCount;
+    if (increaseNewRefCount && _refCount)
+    {
+        _refCount->refCount++;
+    }
+    if (refCount && --refCount->refCount == 0) [[gnu::unlikely]]
+    {
+        refCount->weakRefCount++; // ensure the ref count is not destructed elsewhere
+        rtos_restoreIrqs(irq); // 1
+        refCount->DestructObject();
+        irq = rtos_disableIrqs(); // 2
+        if (--refCount->weakRefCount == 0) [[gnu::unlikely]]
+        {
+            rtos_restoreIrqs(irq); // 2
+            delete refCount;
+        }
+        else
+        {
+            rtos_restoreIrqs(irq); // 2
+        }
+    }
+    else
+    {
+        rtos_restoreIrqs(irq); // 1
+    }
+}