Added support for hierarchical defparams

frontends/ast/ast.cc

@@ -1113,8 +1113,13 @@ RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, R
 			goto rewrite_parameter;
 		}
 	}
-	if (parameters.size() > 0)
-		log_error("Requested parameter `%s' does not exist in module `%s'!\n", parameters.begin()->first.c_str(), stripped_name.c_str());
+
+	for (auto param : parameters) {
+		AstNode *defparam = new AstNode(AST_DEFPARAM, new AstNode(AST_IDENTIFIER));
+		defparam->children[0]->str = param.first.str();
+		defparam->children.push_back(AstNode::mkconst_bits(param.second.bits, (param.second.flags & RTLIL::CONST_FLAG_SIGNED) != 0));
+		new_ast->children.push_back(defparam);
+	}
 
 	std::string modname;
 

frontends/ast/simplify.cc

@@ -685,19 +685,40 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		current_scope.clear();
 
 	// convert defparam nodes to cell parameters
-	if (type == AST_DEFPARAM && !str.empty()) {
-		size_t pos = str.rfind('.');
+	if (type == AST_DEFPARAM && !children.empty())
+	{
+		if (children[0]->type != AST_IDENTIFIER)
+			log_error("Module name in defparam at %s:%d contains non-constant expressions!\n", filename.c_str(), linenum);
+
+		string modname, paramname = children[0]->str;
+
+		size_t pos = paramname.rfind('.');
+
+		while (pos != 0 && pos != std::string::npos)
+		{
+			modname = paramname.substr(0, pos);
+
+			if (current_scope.count(modname))
+				break;
+
+			pos = paramname.rfind('.', pos - 1);
+		}
+
 		if (pos == std::string::npos)
-			log_error("Defparam `%s' does not contain a dot (module/parameter separator) at %s:%d!\n",
-					RTLIL::unescape_id(str).c_str(), filename.c_str(), linenum);
-		std::string modname = str.substr(0, pos), paraname = "\\" + str.substr(pos+1);
-		if (current_scope.count(modname) == 0 || current_scope.at(modname)->type != AST_CELL)
-			log_error("Can't find cell for defparam `%s . %s` at %s:%d!\n", RTLIL::unescape_id(modname).c_str(), RTLIL::unescape_id(paraname).c_str(), filename.c_str(), linenum);
-		AstNode *cell = current_scope.at(modname), *paraset = clone();
+			log_error("Can't find object for defparam `%s` at %s:%d!\n", RTLIL::unescape_id(paramname).c_str(), filename.c_str(), linenum);
+
+		paramname = "\\" + paramname.substr(pos+1);
+
+		if (current_scope.at(modname)->type != AST_CELL)
+			log_error("Defparam argument `%s . %s` does not match a cell at %s:%d!\n",
+					RTLIL::unescape_id(modname).c_str(), RTLIL::unescape_id(paramname).c_str(), filename.c_str(), linenum);
+
+		AstNode *paraset = new AstNode(AST_PARASET, children[1]->clone(), GetSize(children) > 2 ? children[2]->clone() : NULL);
+		paraset->str = paramname;
+
+		AstNode *cell = current_scope.at(modname);
 		cell->children.insert(cell->children.begin() + 1, paraset);
-		paraset->type = AST_PARASET;
-		paraset->str = paraname;
-		str.clear();
+		delete_children();
 	}
 
 	// resolve constant prefixes

frontends/verilog/verilog_parser.y

@@ -666,14 +666,13 @@ defparam_decl_list:
 	single_defparam_decl | defparam_decl_list ',' single_defparam_decl;
 
 single_defparam_decl:
-	range hierarchical_id '=' expr {
+	range rvalue '=' expr {
 		AstNode *node = new AstNode(AST_DEFPARAM);
-		node->str = *$2;
+		node->children.push_back($2);
 		node->children.push_back($4);
 		if ($1 != NULL)
 			node->children.push_back($1);
 		ast_stack.back()->children.push_back(node);
-		delete $2;
 	};
 
 wire_decl:

passes/hierarchy/hierarchy.cc

@@ -213,7 +213,7 @@ bool expand_module(RTLIL::Design *design, RTLIL::Module *module, bool flag_check
 					log_error("Module `%s' referenced in module `%s' in cell `%s' does not have a port named '%s'.\n",
 							log_id(cell->type), log_id(module), log_id(cell), log_id(conn.first));
 			for (auto &param : cell->parameters)
-				if (mod->avail_parameters.count(param.first) == 0 && param.first[0] != '$')
+				if (mod->avail_parameters.count(param.first) == 0 && param.first[0] != '$' && strchr(param.first.c_str(), '.') == NULL)
 					log_error("Module `%s' referenced in module `%s' in cell `%s' does not have a parameter named '%s'.\n",
 							log_id(cell->type), log_id(module), log_id(cell), log_id(param.first));
 		}

tests/simple/hierdefparam.v

@@ -0,0 +1,23 @@
+module hierdefparam_top(input [7:0] A, output [7:0] Y);
+  generate begin:foo
+    hierdefparam_a mod_a(.A(A), .Y(Y));
+  end endgenerate
+  defparam foo.mod_a.bar[0].mod_b.addvalue = 42;
+  defparam foo.mod_a.bar[1].mod_b.addvalue = 43;
+endmodule
+
+module hierdefparam_a(input [7:0] A, output [7:0] Y);
+  genvar i;
+  generate
+    for (i = 0; i < 2; i=i+1) begin:bar
+      wire [7:0] a, y;
+      hierdefparam_b mod_b(.A(a), .Y(y));
+    end
+  endgenerate
+  assign bar[0].a = A, bar[1].a = bar[0].y, Y = bar[1].y;
+endmodule
+
+module hierdefparam_b(input [7:0] A, output [7:0] Y);
+  parameter [7:0] addvalue = 44;
+  assign Y = A + addvalue;
+endmodule