Progress in new BTOR back-end

1 files changed, 97 insertions, 36 deletions

diff --git a/backends/btor/btor.cc b/backends/btor/btor.cc
index 61caf57e4..2a98d1aba 100644
--- a/backends/btor/btor.cc
+++ b/backends/btor/btor.cc
@@ -58,16 +58,42 @@ struct BtorWorker
 	// nids for constants
 	dict<Const, int> consts;
 
-	// ff inputs that need to be evaluated (<nid>, <d>)
-	vector<pair<int, SigSpec>> ff_todo;
+	// ff inputs that need to be evaluated (<nid>, <ff_cell>)
+	vector<pair<int, Cell*>> ff_todo;
 
 	pool<Cell*> cell_recursion_guard;
+	pool<string> output_symbols;
+	string indent;
+
+	void btorf(const char *fmt, ...)
+	{
+		va_list ap;
+		va_start(ap, fmt);
+		f << indent << vstringf(fmt, ap);
+		va_end(ap);
+	}
+
+	void btorf_push(const string &id)
+	{
+		if (verbose) {
+			f << indent << stringf("  ; begin %s\n", id.c_str());
+			indent += "    ";
+		}
+	}
+
+	void btorf_pop(const string &id)
+	{
+		if (verbose) {
+			indent = indent.substr(4);
+			f << indent << stringf("  ; end %s\n", id.c_str());
+		}
+	}
 
 	int get_bv_sid(int width)
 	{
 		if (sorts_bv.count(width) == 0) {
 			int nid = next_nid++;
-			f << stringf("%d sort bitvec %d\n", nid, width);
+			btorf("%d sort bitvec %d\n", nid, width);
 			sorts_bv[width] = nid;
 		}
 		return sorts_bv.at(width);
@@ -86,6 +112,7 @@ struct BtorWorker
 	{
 		log_assert(cell_recursion_guard.count(cell) == 0);
 		cell_recursion_guard.insert(cell);
+		btorf_push(log_id(cell));
 
 		if (cell->type.in("$add", "$sub", "$xor"))
 		{
@@ -107,14 +134,14 @@ struct BtorWorker
 			int nid_b = get_sig_nid(cell->getPort("\\B"), width, b_signed);
 
 			int nid = next_nid++;
-			f << stringf("%d %s %d %d %d ; %s\n", nid, btor_op.c_str(), sid, nid_a, nid_b, log_id(cell));
+			btorf("%d %s %d %d %d\n", nid, btor_op.c_str(), sid, nid_a, nid_b);
 
 			SigSpec sig = sigmap(cell->getPort("\\Y"));
 
 			if (GetSize(sig) < width) {
 				int sid = get_bv_sid(GetSize(sig));
 				int nid2 = next_nid++;
-				f << stringf("%d slice %d %d %d 0 ; %s\n", nid2, sid, nid, GetSize(sig)-1, log_id(cell));
+				btorf("%d slice %d %d %d 0\n", nid2, sid, nid, GetSize(sig)-1);
 				nid = nid2;
 			}
 
@@ -135,18 +162,18 @@ struct BtorWorker
 
 			if (GetSize(cell->getPort("\\A")) > 1) {
 				int nid_red_a = next_nid++;
-				f << stringf("%d redor %d %d\n", nid_red_a, sid, nid_a);
+				btorf("%d redor %d %d\n", nid_red_a, sid, nid_a);
 				nid_a = nid_red_a;
 			}
 
 			if (GetSize(cell->getPort("\\B")) > 1) {
 				int nid_red_b = next_nid++;
-				f << stringf("%d redor %d %d\n", nid_red_b, sid, nid_b);
+				btorf("%d redor %d %d\n", nid_red_b, sid, nid_b);
 				nid_b = nid_red_b;
 			}
 
 			int nid = next_nid++;
-			f << stringf("%d %s %d %d %d ; %s\n", nid, btor_op.c_str(), sid, nid_a, nid_b, log_id(cell));
+			btorf("%d %s %d %d %d\n", nid, btor_op.c_str(), sid, nid_a, nid_b);
 
 			SigSpec sig = sigmap(cell->getPort("\\Y"));
 
@@ -154,7 +181,7 @@ struct BtorWorker
 				int sid = get_bv_sid(GetSize(sig));
 				int zeros_nid = get_sig_nid(Const(0, GetSize(sig)-1));
 				int nid2 = next_nid++;
-				f << stringf("%d concat %d %d %d ; %s\n", nid2, sid, zeros_nid, nid, log_id(cell));
+				btorf("%d concat %d %d %d\n", nid2, sid, zeros_nid, nid);
 				nid = nid2;
 			}
 
@@ -175,7 +202,7 @@ struct BtorWorker
 
 			int sid = get_bv_sid(GetSize(sig_y));
 			int nid = next_nid++;
-			f << stringf("%d ite %d %d %d %d ; %s\n", nid, sid, nid_s, nid_b, nid_a, log_id(cell));
+			btorf("%d ite %d %d %d %d\n", nid, sid, nid_s, nid_b, nid_a);
 
 			add_nid_sig(nid, sig_y);
 			goto okay;
@@ -195,9 +222,13 @@ struct BtorWorker
 
 			int sid = get_bv_sid(GetSize(sig_q));
 			int nid = next_nid++;
-			f << stringf("%d state %d %s ; %s\n", nid, sid, symbol.c_str(), log_id(cell));
 
-			ff_todo.push_back(make_pair(nid, sig_d));
+			if (output_symbols.count(symbol))
+				btorf("%d state %d\n", nid, sid);
+			else
+				btorf("%d state %d %s\n", nid, sid, symbol.c_str());
+
+			ff_todo.push_back(make_pair(nid, cell));
 			add_nid_sig(nid, sig_q);
 			goto okay;
 		}
@@ -212,9 +243,9 @@ struct BtorWorker
 				int one_nid = get_sig_nid(Const(1, 1));
 				int zero_nid = get_sig_nid(Const(0, 1));
 				initstate_nid = next_nid++;
-				f << stringf("%d state %d ; initstate\n", initstate_nid, sid);
-				f << stringf("%d init %d %d %d ; initstate\n", next_nid++, sid, initstate_nid, one_nid);
-				f << stringf("%d next %d %d %d ; initstate\n", next_nid++, sid, initstate_nid, zero_nid);
+				btorf("%d state %d\n", initstate_nid, sid);
+				btorf("%d init %d %d %d\n", next_nid++, sid, initstate_nid, one_nid);
+				btorf("%d next %d %d %d\n", next_nid++, sid, initstate_nid, zero_nid);
 			}
 
 			add_nid_sig(initstate_nid, sig_y);
@@ -224,6 +255,7 @@ struct BtorWorker
 		log_error("Unsupported cell type: %s (%s)\n", log_id(cell->type), log_id(cell));
 
 	okay:
+		btorf_pop(log_id(cell));
 		cell_recursion_guard.erase(cell);
 	}
 
@@ -253,7 +285,7 @@ struct BtorWorker
 						if (consts.count(c) == 0) {
 							int sid = get_bv_sid(GetSize(c));
 							int nid = next_nid++;
-							f << stringf("%d const %d %s\n", nid, sid, c.as_string().c_str());
+							btorf("%d const %d %s\n", nid, sid, c.as_string().c_str());
 							consts[c] = nid;
 							nid_width[nid] = GetSize(c);
 						}
@@ -295,7 +327,7 @@ struct BtorWorker
 				if (lower != 0 || upper+1 != nid_width.at(nid2)) {
 					int sid = get_bv_sid(upper-lower+1);
 					nid3 = next_nid++;
-					f << stringf("%d slice %d %d %d %d\n", nid3, sid, nid2, upper, lower);
+					btorf("%d slice %d %d %d %d\n", nid3, sid, nid2, upper, lower);
 				}
 
 				int nid4 = nid3;
@@ -303,7 +335,7 @@ struct BtorWorker
 				if (nid >= 0) {
 					int sid = get_bv_sid(width+upper-lower+1);
 					int nid4 = next_nid++;
-					f << stringf("%d concat %d %d %d\n", nid4, sid, nid, nid3);
+					btorf("%d concat %d %d %d\n", nid4, sid, nid, nid3);
 				}
 
 				width += upper-lower+1;
@@ -322,14 +354,14 @@ struct BtorWorker
 			{
 				int sid = get_bv_sid(to_width);
 				int nid2 = next_nid++;
-				f << stringf("%d slice %d %d %d 0\n", nid2, sid, nid, to_width-1);
+				btorf("%d slice %d %d %d 0\n", nid2, sid, nid, to_width-1);
 				nid = nid2;
 			}
 			else
 			{
 				int sid = get_bv_sid(to_width);
 				int nid2 = next_nid++;
-				f << stringf("%d %s %d %d %d\n", nid2, is_signed ? "sext" : "uext",
+				btorf("%d %s %d %d %d\n", nid2, is_signed ? "sext" : "uext",
 						sid, nid, to_width - GetSize(sig));
 				nid = nid2;
 			}
@@ -341,6 +373,8 @@ struct BtorWorker
 	BtorWorker(std::ostream &f, RTLIL::Module *module, bool verbose) :
 			f(f), sigmap(module), module(module), verbose(verbose)
 	{
+		btorf_push("inputs");
+
 		for (auto wire : module->wires())
 		{
 			if (!wire->port_id || !wire->port_input)
@@ -350,10 +384,12 @@ struct BtorWorker
 			int sid = get_bv_sid(GetSize(sig));
 			int nid = next_nid++;
 
-			f << stringf("%d input %d %s\n", nid, sid, log_id(wire));
+			btorf("%d input %d %s\n", nid, sid, log_id(wire));
 			add_nid_sig(nid, sig);
 		}
 
+		btorf_pop("inputs");
+
 		for (auto cell : module->cells())
 		for (auto &conn : cell->connections())
 		{
@@ -365,18 +401,28 @@ struct BtorWorker
 		}
 
 		for (auto wire : module->wires())
+			if (wire->port_output)
+				output_symbols.insert(log_id(wire));
+
+		for (auto wire : module->wires())
 		{
 			if (!wire->port_id || !wire->port_output)
 				continue;
 
+			btorf_push(stringf("output %s", log_id(wire)));
+
 			int nid = get_sig_nid(wire);
-			f << stringf("%d output %d %s\n", next_nid++, nid, log_id(wire));
+			btorf("%d output %d %s\n", next_nid++, nid, log_id(wire));
+
+			btorf_pop(stringf("output %s", log_id(wire)));
 		}
 
 		for (auto cell : module->cells())
 		{
 			if (cell->type == "$assume")
 			{
+				btorf_push(log_id(cell));
+
 				int sid = get_bv_sid(1);
 				int nid_a = get_sig_nid(cell->getPort("\\A"));
 				int nid_en = get_sig_nid(cell->getPort("\\EN"));
@@ -384,13 +430,17 @@ struct BtorWorker
 				int nid_a_or_not_en = next_nid++;
 				int nid = next_nid++;
 
-				f << stringf("%d not %d %d\n", nid_not_en, sid, nid_en);
-				f << stringf("%d or %d %d %d\n", nid_a_or_not_en, sid, nid_a, nid_not_en);
-				f << stringf("%d constraint %d ; %s\n", nid, nid_a_or_not_en, log_id(cell));
+				btorf("%d not %d %d\n", nid_not_en, sid, nid_en);
+				btorf("%d or %d %d %d\n", nid_a_or_not_en, sid, nid_a, nid_not_en);
+				btorf("%d constraint %d\n", nid, nid_a_or_not_en);
+
+				btorf_pop(log_id(cell));
 			}
 
 			if (cell->type == "$assert")
 			{
+				btorf_push(log_id(cell));
+
 				int sid = get_bv_sid(1);
 				int nid_a = get_sig_nid(cell->getPort("\\A"));
 				int nid_en = get_sig_nid(cell->getPort("\\EN"));
@@ -398,22 +448,30 @@ struct BtorWorker
 				int nid_en_and_not_a = next_nid++;
 				int nid = next_nid++;
 
-				f << stringf("%d not %d %d\n", nid_not_a, sid, nid_a);
-				f << stringf("%d and %d %d %d\n", nid_en_and_not_a, sid, nid_en, nid_not_a);
-				f << stringf("%d bad %d ; %s\n", nid, nid_en_and_not_a, log_id(cell));
+				btorf("%d not %d %d\n", nid_not_a, sid, nid_a);
+				btorf("%d and %d %d %d\n", nid_en_and_not_a, sid, nid_en, nid_not_a);
+				btorf("%d bad %d\n", nid, nid_en_and_not_a);
+
+				btorf_pop(log_id(cell));
 			}
 		}
 
 		while (!ff_todo.empty())
 		{
-			vector<pair<int, SigSpec>> todo;
+			vector<pair<int, Cell*>> todo;
 			todo.swap(ff_todo);
 
 			for (auto &it : todo)
 			{
-				int nid = get_sig_nid(it.second);
-				int sid = get_bv_sid(GetSize(it.second));
-				f << stringf("%d next %d %d %d\n", next_nid++, sid, it.first, nid);
+				btorf_push(stringf("next %s", log_id(it.second)));
+
+				SigSpec sig = sigmap(it.second->getPort("\\D"));
+
+				int nid = get_sig_nid(sig);
+				int sid = get_bv_sid(GetSize(sig));
+				btorf("%d next %d %d %d\n", next_nid++, sid, it.first, nid);
+
+				btorf_pop(stringf("next %s", log_id(it.second)));
 			}
 		}
 	}
@@ -429,6 +487,9 @@ struct BtorBackend : public Backend {
 		log("\n");
 		log("Write a BTOR description of the current design.\n");
 		log("\n");
+		log("  -v\n");
+		log("    Add comments and indentation to BTOR output file\n");
+		log("\n");
 	}
 	virtual void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
@@ -439,10 +500,10 @@ struct BtorBackend : public Backend {
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
 		{
-			// if (args[argidx] == "-verbose") {
-			// 	verbose = true;
-			// 	continue;
-			// }
+			if (args[argidx] == "-v") {
+				verbose = true;
+				continue;
+			}
 			break;
 		}
 		extra_args(f, filename, args, argidx);