From bac6bff9e62e0f03b3d26756bf7b8642a7c02819 Mon Sep 17 00:00:00 2001
From: Couriersud <couriersud@users.noreply.github.com>
Date: Mon, 28 Oct 2013 21:27:47 +0000
Subject: [PATCH] Netlist: Some hand-crafted optimizations. GCC seems to like
 ugly pointer C more than using readable arrays :-( The speedup is noticeable.

---
 src/emu/machine/netlist.c | 41 +++++-----------------------------
 src/emu/machine/netlist.h | 46 +++++++++++++++++++++++++++------------
 2 files changed, 38 insertions(+), 49 deletions(-)

diff --git a/src/emu/machine/netlist.c b/src/emu/machine/netlist.c
index a72528abaa3..090c626b3b1 100644
--- a/src/emu/machine/netlist.c
+++ b/src/emu/machine/netlist.c
@@ -294,39 +294,11 @@ private:
 };
 
 
-// ----------------------------------------------------------------------------------------
-// netlist_timed_queue
-// ----------------------------------------------------------------------------------------
-
-ATTR_HOT ATTR_ALIGN void netlist_timed_queue::push(const entry_t &e)
-{
-	const netlist_time &t = e.time();
-	if (is_empty() || (t <= item(m_end - 1).time()))
-	{
-		set_item(m_end,  e);
-		m_end++;
-		inc_stat(m_prof_end);
-	}
-	else
-	{
-		int i = m_end;
-		m_end++;
-		while ((i>0) && (t > item(i-1).time()) )
-		{
-			set_item(i, item(i-1));
-			inc_stat(m_prof_sortmove);
-			i--;
-		}
-		set_item(i, e);
-		inc_stat(m_prof_sort);
-	}
-}
-
 // ----------------------------------------------------------------------------------------
 // netdev_mainclock
 // ----------------------------------------------------------------------------------------
 
-ATTR_HOT inline void netdev_mainclock::mc_update(net_output_t &Q, const netlist_time &curtime)
+ATTR_HOT inline void netdev_mainclock::mc_update(net_output_t &Q, const netlist_time curtime)
 {
 	Q.m_new_Q = !Q.m_new_Q;
 	Q.set_time(curtime);
@@ -336,7 +308,6 @@ ATTR_HOT inline void netdev_mainclock::mc_update(net_output_t &Q, const netlist_
 ATTR_COLD NETLIB_START(netdev_mainclock)
 {
 	register_output("Q", m_Q);
-	//register_input("FB", m_feedback);
 
 	register_param("FREQ", m_freq, 7159000.0 * 5);
 	m_inc = netlist_time::from_hz(m_freq.Value()*2);
@@ -520,7 +491,7 @@ ATTR_HOT ATTR_ALIGN void netlist_base_t::process_list(INT32 &atime)
 	{
 		while ( (atime > 0) && (m_queue.is_not_empty()))
 		{
-			const queue_t::entry_t &e = m_queue.pop();
+			const queue_t::entry_t e = m_queue.pop();
 			update_time(e.time(), atime);
 
 			if (FATAL_ERROR_AFTER_NS)
@@ -548,21 +519,21 @@ ATTR_HOT ATTR_ALIGN void netlist_base_t::process_list(INT32 &atime)
 		{
 			if (m_queue.is_not_empty())
 			{
-				while (m_queue.peek().time() > m_mainclock->m_Q.time())
+				while (m_queue.peek().time() > mcQ.time())
 				{
-					update_time(m_mainclock->m_Q.time(), atime);
+					update_time(mcQ.time(), atime);
 
 					netdev_mainclock::mc_update(mcQ, time() + inc);
 
 				}
-				const queue_t::entry_t &e = m_queue.pop();
+				const queue_t::entry_t e = m_queue.pop();
 
 				update_time(e.time(), atime);
 
 				e.object().update_devs();
 
 			} else {
-				update_time(m_mainclock->m_Q.time(), atime);
+				update_time(mcQ.time(), atime);
 
 				netdev_mainclock::mc_update(mcQ, time() + inc);
 			}
diff --git a/src/emu/machine/netlist.h b/src/emu/machine/netlist.h
index 186588199be..eaba700a7c7 100644
--- a/src/emu/machine/netlist.h
+++ b/src/emu/machine/netlist.h
@@ -365,25 +365,45 @@ public:
 		clear();
 	}
 
-	ATTR_HOT inline bool is_empty() const { return (m_end == 0); }
-	ATTR_HOT inline bool is_not_empty() const { return (m_end != 0); }
+	ATTR_HOT inline bool is_empty() const { return (m_end == &m_list[0]); }
+	ATTR_HOT inline bool is_not_empty() const { return (m_end > &m_list[0]); }
 
-	ATTR_HOT ATTR_ALIGN void push(const entry_t &e);
-
-	ATTR_HOT inline const entry_t &pop()
+	ATTR_HOT ATTR_ALIGN inline void push(const entry_t &e)
 	{
-		m_end--;
-		return item(m_end);
+		if (is_empty() || (e.time() <= (m_end - 1)->time()))
+		{
+			*m_end = e;
+			m_end++;
+			//inc_stat(m_prof_end);
+		}
+		else
+		{
+			entry_t *i = m_end++;
+			while ((i>&m_list[0]) && (e.time() > (i-1)->time()) )
+			{
+				i--;
+				*(i+1) = *i;
+				//inc_stat(m_prof_sortmove);
+			}
+			*i = e;
+			//inc_stat(m_prof_sort);
+		}
 	}
 
-	ATTR_HOT inline const entry_t &peek() const
+	ATTR_HOT inline const entry_t pop()
 	{
-		return item(m_end-1);
+		m_end--;
+		return *m_end;
+	}
+
+	ATTR_HOT inline const entry_t peek() const
+	{
+		return *(m_end-1);
 	}
 
 	ATTR_COLD void clear()
 	{
-		m_end = 0;
+		m_end = &m_list[0];
 	}
 	// profiling
 
@@ -392,10 +412,8 @@ public:
 	INT32   m_prof_sortmove;
 	INT32   m_prof_sort;
 private:
-	ATTR_HOT inline const entry_t &item(const UINT32 x) const { return m_list[x]; }
-	ATTR_HOT inline void set_item(const UINT32 x, const entry_t &aitem) { m_list[x] = aitem; }
 
-	UINT32 m_end;
+	entry_t *m_end;
 	entry_t m_list[SIZE + 1];
 
 };
@@ -1188,7 +1206,7 @@ NETLIB_DEVICE_WITH_PARAMS(netdev_mainclock,
 	net_param_t m_freq;
 	netlist_time m_inc;
 
-	ATTR_HOT inline static void mc_update(net_output_t &Q, const netlist_time &curtime);
+	ATTR_HOT inline static void mc_update(net_output_t &Q, const netlist_time curtime);
 );
 
 // ----------------------------------------------------------------------------------------