From 636894b02f9e920cc122b150a5356188da60edd7 Mon Sep 17 00:00:00 2001
From: couriersud <couriersud@gmx.org>
Date: Sun, 26 Jan 2020 21:22:13 +0100
Subject: [PATCH] netlist: MAJOR bug fix. Expect other bugs to surface.
 [Couriersud]

This commit fixes an issue with parsing netlists. To cut a long story
short: The separation of nets into independant groups of nets failed
under some circumstances for four terminal devices (controlled
voltage/current devices). Everything worked as long as an external
feedback loop existed. Without external feedback loop, the separation
would either fail or create "false" separated nets.
This fix also highlighted an issue with cmos switches (4066/4016).

There is a slight chance that other bugs may surface due to this change.
---
 src/lib/netlist/devices/nld_4066.cpp  |  9 ++++--
 src/lib/netlist/nl_config.h           |  2 +-
 src/lib/netlist/solver/nld_solver.cpp | 41 +++++++++++++++++++++------
 3 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/src/lib/netlist/devices/nld_4066.cpp b/src/lib/netlist/devices/nld_4066.cpp
index bd9b7bfe004..a45b2ab9e22 100644
--- a/src/lib/netlist/devices/nld_4066.cpp
+++ b/src/lib/netlist/devices/nld_4066.cpp
@@ -23,6 +23,7 @@ namespace netlist
 		, m_R(*this, "R")
 		, m_control(*this, "CTL")
 		, m_base_r(*this, "BASER", nlconst::magic(270.0))
+		, m_last(*this, "m_last", false)
 		{
 		}
 
@@ -34,7 +35,8 @@ namespace netlist
 		analog::NETLIB_SUB(R_base) m_R;
 
 		analog_input_t             m_control;
-		param_fp_t             m_base_r;
+		param_fp_t             	   m_base_r;
+		state_var<bool>			   m_last;
 	};
 
 	NETLIB_RESET(CD4066_GATE)
@@ -53,6 +55,7 @@ namespace netlist
 		nl_fptype in = m_control() - m_supply.GND().Q_Analog();
 		nl_fptype rON = m_base_r() * nlconst::magic(5.0) / sup;
 		nl_fptype R = -nlconst::one();
+		bool new_state(false);
 
 		if (in < low)
 		{
@@ -61,10 +64,12 @@ namespace netlist
 		else if (in > high)
 		{
 			R = rON;
+			new_state = true;
 		}
 		//printf("%s %f %f %g\n", name().c_str(), sup, in, R);
-		if (R > nlconst::zero())
+		if (R > nlconst::zero() && (m_last != new_state))
 		{
+			m_last = new_state;
 			m_R.update();
 			m_R.set_R(R);
 			m_R.solve_later();
diff --git a/src/lib/netlist/nl_config.h b/src/lib/netlist/nl_config.h
index 3d50da284c4..f6b594af977 100644
--- a/src/lib/netlist/nl_config.h
+++ b/src/lib/netlist/nl_config.h
@@ -17,7 +17,7 @@
 ///
 /// \brief Version - Minor.
 ///
-#define NL_VERSION_MINOR           9
+#define NL_VERSION_MINOR           10
 /// \brief Version - Patch level.
 ///
 #define NL_VERSION_PATCHLEVEL      0
diff --git a/src/lib/netlist/solver/nld_solver.cpp b/src/lib/netlist/solver/nld_solver.cpp
index 09920dfd73c..a4eedc38ed7 100644
--- a/src/lib/netlist/solver/nld_solver.cpp
+++ b/src/lib/netlist/solver/nld_solver.cpp
@@ -253,28 +253,45 @@ namespace devices
 	struct net_splitter
 	{
 
-		bool already_processed(const analog_net_t &n) const
+		bool already_processed(const analog_net_t &n)
 		{
 			// no need to process rail nets - these are known variables
 			if (n.isRailNet())
 				return true;
+			// First check if it is in a previous group.
+			// In this case we need to merge this group into the current group
+			if (groupspre.size() > 1)
+			{
+				for (std::size_t i = 0; i<groupspre.size() - 1; i++)
+					if (plib::container::contains(groupspre[i], &n))
+					{
+						// copy all nets
+						for (auto & cn : groupspre[i])
+							if (!plib::container::contains(groupspre.back(), cn))
+								groupspre.back().push_back(cn);
+						// clear
+						groupspre[i].clear();
+						return true;
+					}
+			}
 			// if it's already processed - no need to continue
-			for (auto & grp : groups)
-				if (plib::container::contains(grp, &n))
-					return true;
+			if (!groupspre.empty() && plib::container::contains(groupspre.back(), &n))
+				return true;
 			return false;
 		}
 
 		void process_net(netlist_state_t &netlist, analog_net_t &n)
 		{
 			// ignore empty nets. FIXME: print a warning message
+			netlist.log().verbose("Net {}", n.name());
 			if (n.num_cons() == 0)
 				return;
 			// add the net
-			groups.back().push_back(&n);
+			groupspre.back().push_back(&n);
 			// process all terminals connected to this net
 			for (auto &term : n.core_terms())
 			{
+				netlist.log().verbose("Term {} {}", term->name(), (int) term->type());
 				// only process analog terminals
 				if (term->is_type(detail::terminal_type::TERMINAL))
 				{
@@ -282,6 +299,7 @@ namespace devices
 					// check the connected terminal
 					// analog_net_t &connected_net = pt->connected_terminal()->net();
 					analog_net_t &connected_net = netlist.setup().get_connected_terminal(*pt)->net();
+					netlist.log().verbose("  Connected net {}", connected_net.name());
 					if (!already_processed(connected_net))
 						process_net(netlist, connected_net);
 				}
@@ -292,22 +310,29 @@ namespace devices
 		{
 			for (auto & net : netlist.nets())
 			{
-				netlist.log().debug("processing {1}\n", net->name());
+				netlist.log().debug("processing {1}", net->name());
+				netlist.log().verbose("processing {1}", net->name());
 				if (!net->isRailNet() && net->num_cons() > 0)
 				{
-					netlist.log().debug("   ==> not a rail net\n");
+					netlist.log().debug("   ==> not a rail net");
+					netlist.log().verbose("   ==> not a rail net");
 					// Must be an analog net
 					auto &n = *static_cast<analog_net_t *>(net.get());
 					if (!already_processed(n))
 					{
-						groups.emplace_back(analog_net_t::list_t());
+						groupspre.emplace_back(analog_net_t::list_t());
 						process_net(netlist, n);
 					}
 				}
 			}
+			for (auto &g : groupspre)
+				if (!g.empty())
+					groups.push_back(g);
 		}
 
 		std::vector<analog_net_t::list_t> groups;
+	private:
+		std::vector<analog_net_t::list_t> groupspre;
 	};
 
 	void NETLIB_NAME(solver)::post_start()