6 files changed, 44 insertions, 10 deletions

diff --git a/frontends/ast/ast.cc b/frontends/ast/ast.cc
index be04d5536..037a9f3ee 100644
--- a/frontends/ast/ast.cc
+++ b/frontends/ast/ast.cc
@@ -1067,7 +1067,7 @@ AstModule::~AstModule()
 }
 
 // create a new parametric module (when needed) and return the name of the generated module
-RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters)
+RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters, bool)
 {
 	std::string stripped_name = name.str();
 
diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h
index a5d5ee30a..d1e2c78d1 100644
--- a/frontends/ast/ast.h
+++ b/frontends/ast/ast.h
@@ -283,7 +283,7 @@ namespace AST
 		AstNode *ast;
 		bool nolatches, nomeminit, nomem2reg, mem2reg, lib, noopt, icells, autowire;
 		virtual ~AstModule();
-		virtual RTLIL::IdString derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters);
+		virtual RTLIL::IdString derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters, bool mayfail);
 		virtual RTLIL::Module *clone() const;
 	};
 
diff --git a/kernel/rtlil.cc b/kernel/rtlil.cc
index 3e873054f..fb3d9dbe9 100644
--- a/kernel/rtlil.cc
+++ b/kernel/rtlil.cc
@@ -639,8 +639,10 @@ RTLIL::Module::~Module()
 		delete it->second;
 }
 
-RTLIL::IdString RTLIL::Module::derive(RTLIL::Design*, dict<RTLIL::IdString, RTLIL::Const>)
+RTLIL::IdString RTLIL::Module::derive(RTLIL::Design*, dict<RTLIL::IdString, RTLIL::Const>, bool mayfail)
 {
+	if (mayfail)
+		return RTLIL::IdString();
 	log_error("Module `%s' is used with parameters but is not parametric!\n", id2cstr(name));
 }
 
diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index fc29e1e65..a251b4252 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -906,7 +906,7 @@ public:
 
 	Module();
 	virtual ~Module();
-	virtual RTLIL::IdString derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters);
+	virtual RTLIL::IdString derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters, bool mayfail = false);
 	virtual size_t count_id(RTLIL::IdString id);
 
 	virtual void sort();
diff --git a/passes/hierarchy/hierarchy.cc b/passes/hierarchy/hierarchy.cc
index c460fbbfc..c680dbbd8 100644
--- a/passes/hierarchy/hierarchy.cc
+++ b/passes/hierarchy/hierarchy.cc
@@ -620,17 +620,26 @@ struct HierarchyPass : public Pass {
 			}
 		}
 
+		std::set<Module*> blackbox_derivatives;
+
 		for (auto module : design->modules())
 		for (auto cell : module->cells())
 		{
-			if (GetSize(cell->parameters) != 0)
-				continue;
-
 			Module *m = design->module(cell->type);
 
-			if (m == nullptr || m->get_bool_attribute("\\blackbox"))
+			if (m == nullptr)
 				continue;
 
+			if (m->get_bool_attribute("\\blackbox") && !cell->parameters.empty()) {
+				IdString new_m_name = m->derive(design, cell->parameters, true);
+				if (new_m_name.empty())
+					continue;
+				if (new_m_name != m->name) {
+					m = design->module(new_m_name);
+					blackbox_derivatives.insert(m);
+				}
+			}
+
 			for (auto &conn : cell->connections())
 			{
 				Wire *w = m->wire(conn.first);
@@ -673,6 +682,9 @@ struct HierarchyPass : public Pass {
 			}
 		}
 
+		for (auto module : blackbox_derivatives)
+			design->remove(module);
+
 		log_pop();
 	}
 } HierarchyPass;
diff --git a/passes/techmap/libparse.cc b/passes/techmap/libparse.cc
index d5254c029..d3b1ff02f 100644
--- a/passes/techmap/libparse.cc
+++ b/passes/techmap/libparse.cc
@@ -100,8 +100,15 @@ int LibertyParser::lexer(std::string &str)
 				break;
 		}
 		f.unget();
-		// fprintf(stderr, "LEX: identifier >>%s<<\n", str.c_str());
-		return 'v';
+		if (str == "+" || str == "-") {
+			/* Single operator is not an identifier */
+			// fprintf(stderr, "LEX: char >>%s<<\n", str.c_str());
+			return str[0];
+		}
+		else {
+			// fprintf(stderr, "LEX: identifier >>%s<<\n", str.c_str());
+			return 'v';
+		}
 	}
 
 	if (c == '"') {
@@ -191,6 +198,19 @@ LibertyAst *LibertyParser::parse()
 			tok = lexer(ast->value);
 			if (tok != 'v')
 				error();
+			tok = lexer(str);
+			while (tok == '+' || tok == '-' || tok == '*' || tok == '/') {
+				ast->value += tok;
+				tok = lexer(str);
+				if (tok != 'v')
+					error();
+				ast->value += str;
+				tok = lexer(str);
+			}
+			if (tok == ';')
+				break;
+			else
+				error();
 			continue;
 		}