threadsafe_queue: Remove NeedSize template parameter

The necessity of this parameter is dubious at best, and in 2019 probably
offers completely negligible savings as opposed to just leaving this
enabled. This removes it and simplifies the overall interface.

src/common/threadsafe_queue.h

@@ -15,10 +15,10 @@
 #include "common/common_types.h"
 
 namespace Common {
-template <typename T, bool NeedSize = true>
+template <typename T>
 class SPSCQueue {
 public:
-    SPSCQueue() : size(0) {
+    SPSCQueue() {
         write_ptr = read_ptr = new ElementPtr();
     }
     ~SPSCQueue() {
@@ -27,12 +27,11 @@ public:
     }
 
     u32 Size() const {
-        static_assert(NeedSize, "using Size() on FifoQueue without NeedSize");
         return size.load();
     }
 
     bool Empty() const {
-        return !read_ptr->next.load();
+        return Size() == 0;
     }
 
     T& Front() const {
@@ -48,14 +47,14 @@ public:
         ElementPtr* new_ptr = new ElementPtr();
         write_ptr->next.store(new_ptr, std::memory_order_release);
         write_ptr = new_ptr;
-        if (NeedSize)
-            size++;
         cv.notify_one();
+
+        ++size;
     }
 
     void Pop() {
-        if (NeedSize)
-            size--;
+        --size;
+
         ElementPtr* tmpptr = read_ptr;
         // advance the read pointer
         read_ptr = tmpptr->next.load();
@@ -68,8 +67,7 @@ public:
         if (Empty())
             return false;
 
-        if (NeedSize)
-            size--;
+        --size;
 
         ElementPtr* tmpptr = read_ptr;
         read_ptr = tmpptr->next.load(std::memory_order_acquire);
@@ -123,7 +121,7 @@ private:
 // a simple thread-safe,
 // single reader, multiple writer queue
 
-template <typename T, bool NeedSize = true>
+template <typename T>
 class MPSCQueue {
 public:
     u32 Size() const {
@@ -162,7 +160,7 @@ public:
     }
 
 private:
-    SPSCQueue<T, NeedSize> spsc_queue;
+    SPSCQueue<T> spsc_queue;
     std::mutex write_lock;
 };
 } // namespace Common

src/core/core_timing.h

@@ -218,7 +218,7 @@ private:
     u64 event_fifo_id = 0;
     // the queue for storing the events from other threads threadsafe until they will be added
     // to the event_queue by the emu thread
-    Common::MPSCQueue<Event, false> ts_queue;
+    Common::MPSCQueue<Event> ts_queue;
     s64 idled_cycles = 0;
 
     // Are we in a function that has been called from Advance()