Support module/package/interface/block scope for typedef names.

4 files changed, 56 insertions, 20 deletions

diff --git a/frontends/verilog/verilog_frontend.cc b/frontends/verilog/verilog_frontend.cc
index f2c1c227f..1c88d479b 100644
--- a/frontends/verilog/verilog_frontend.cc
+++ b/frontends/verilog/verilog_frontend.cc
@@ -51,7 +51,6 @@ static void add_package_types(std::map<std::string, AST::AstNode *> &user_types,
 {
 	// prime the parser's user type lookup table with the package qualified names
 	// of typedefed names in the packages seen so far.
-	user_types.clear();
 	for (const auto &pkg : package_list) {
 		log_assert(pkg->type==AST::AST_PACKAGE);
 		for (const auto &node: pkg->children) {
@@ -61,6 +60,8 @@ static void add_package_types(std::map<std::string, AST::AstNode *> &user_types,
 			}
 		}
 	}
+	user_type_stack.clear();
+	user_type_stack.push_back(new UserTypeMap());
 }
 
 struct VerilogFrontend : public Frontend {
diff --git a/frontends/verilog/verilog_frontend.h b/frontends/verilog/verilog_frontend.h
index 73ea51e6c..caa6246ef 100644
--- a/frontends/verilog/verilog_frontend.h
+++ b/frontends/verilog/verilog_frontend.h
@@ -45,8 +45,9 @@ namespace VERILOG_FRONTEND
 	// this function converts a Verilog constant to an AST_CONSTANT node
 	AST::AstNode *const2ast(std::string code, char case_type = 0, bool warn_z = false);
 
-	// names of locally typedef'ed types
-	extern std::map<std::string, AST::AstNode*> user_types;
+	// names of locally typedef'ed types in a stack
+	typedef std::map<std::string, AST::AstNode*> UserTypeMap;
+	extern std::vector<UserTypeMap *> user_type_stack;
 
 	// names of package typedef'ed types
 	extern std::map<std::string, AST::AstNode*> pkg_user_types;
diff --git a/frontends/verilog/verilog_lexer.l b/frontends/verilog/verilog_lexer.l
index 74e8dce7f..bccdf4841 100644
--- a/frontends/verilog/verilog_lexer.l
+++ b/frontends/verilog/verilog_lexer.l
@@ -99,6 +99,18 @@ YYLTYPE old_location;
 #define YY_BUF_SIZE 65536
 
 extern int frontend_verilog_yylex(YYSTYPE *yylval_param, YYLTYPE *yyloc_param);
+
+static bool isUserType(std::string &s)
+{
+	// check current scope then outer scopes for a name
+	for (auto it = user_type_stack.rbegin(); it != user_type_stack.rend(); ++it) {
+		if ((*it)->count(s) > 0) {
+			return true;
+		}
+	}
+	return false;
+}
+
 %}
 
 %option yylineno
@@ -376,7 +388,7 @@ supply1 { return TOK_SUPPLY1; }
 	// package qualifier
 	auto s = std::string("\\") + yytext;
 	if (pkg_user_types.count(s) > 0) {
-		// found it
+		// package qualified typedefed name
 		yylval->string = new std::string(s);
 		return TOK_USER_TYPE;
 	}
@@ -391,7 +403,8 @@ supply1 { return TOK_SUPPLY1; }
 
 [a-zA-Z_$][a-zA-Z0-9_$]* {
 	auto s = std::string("\\") + yytext;
-	if (user_types.count(s) > 0) {
+	if (isUserType(s)) {
+		// previously typedefed name
 		yylval->string = new std::string(s);
 		return TOK_USER_TYPE;
 	}
diff --git a/frontends/verilog/verilog_parser.y b/frontends/verilog/verilog_parser.y
index f7e3afd13..1a195bbfd 100644
--- a/frontends/verilog/verilog_parser.y
+++ b/frontends/verilog/verilog_parser.y
@@ -54,7 +54,7 @@ namespace VERILOG_FRONTEND {
 	std::map<std::string, AstNode*> *attr_list, default_attr_list;
 	std::stack<std::map<std::string, AstNode*> *> attr_list_stack;
 	std::map<std::string, AstNode*> *albuf;
-	std::map<std::string, AstNode*> user_types;
+	std::vector<UserTypeMap*> user_type_stack;
 	std::map<std::string, AstNode*> pkg_user_types;
 	std::vector<AstNode*> ast_stack;
 	struct AstNode *astbuf1, *astbuf2, *astbuf3;
@@ -130,14 +130,10 @@ struct specify_rise_fall {
 static void addTypedefNode(std::string *name, AstNode *node)
 {
 	log_assert(node);
-	// seems to be support for local scoped typedefs in simplify()
-	// and tests redefine types.
-	//if (user_types.count(*name) > 0) {
-	//	frontend_verilog_yyerror("Type already defined.");
-	//}
 	auto *tnode = new AstNode(AST_TYPEDEF, node);
 	tnode->str = *name;
-	user_types[*name] = tnode;
+	auto user_types = user_type_stack.back();
+	(*user_types)[*name] = tnode;
 	if (current_ast_mod && current_ast_mod->type == AST_PACKAGE) {
 		// typedef inside a package so we need the qualified name
 		auto qname = current_ast_mod->str + "::" + (*name).substr(1);
@@ -147,6 +143,17 @@ static void addTypedefNode(std::string *name, AstNode *node)
 	ast_stack.back()->children.push_back(tnode);
 }
 
+static void enterTypeScope()
+{
+	auto user_types = new UserTypeMap();
+	user_type_stack.push_back(user_types);
+}
+
+static void exitTypeScope()
+{
+	user_type_stack.pop_back();
+}
+
 static AstNode *makeRange(int msb = 31, int lsb = 0, bool isSigned = true)
 {
 	auto range = new AstNode(AST_RANGE);
@@ -359,7 +366,7 @@ hierarchical_type_id:
 	;
 
 module:
-	attr TOK_MODULE TOK_ID {
+	attr module_start TOK_ID {
 		do_not_require_port_stubs = false;
 		AstNode *mod = new AstNode(AST_MODULE);
 		ast_stack.back()->children.push_back(mod);
@@ -378,9 +385,12 @@ module:
 		ast_stack.pop_back();
 		log_assert(ast_stack.size() == 1);
 		current_ast_mod = NULL;
-		user_types.clear();
+		exitTypeScope();
 	};
 
+module_start: TOK_MODULE	{ enterTypeScope(); }
+	;
+
 module_para_opt:
 	'#' '(' { astbuf1 = nullptr; } module_para_list { if (astbuf1) delete astbuf1; } ')' | /* empty */;
 
@@ -482,7 +492,7 @@ module_arg:
 	};
 
 package:
-	attr TOK_PACKAGE TOK_ID {
+	attr package_start TOK_ID {
 		AstNode *mod = new AstNode(AST_PACKAGE);
 		ast_stack.back()->children.push_back(mod);
 		ast_stack.push_back(mod);
@@ -492,9 +502,12 @@ package:
 	} ';' package_body TOK_ENDPACKAGE {
 		ast_stack.pop_back();
 		current_ast_mod = NULL;
-		user_types.clear();
+		exitTypeScope();
 	};
 
+package_start: TOK_PACKAGE	{ enterTypeScope(); }
+	;
+
 package_body:
 	package_body package_body_stmt
 	| // optional
@@ -505,7 +518,7 @@ package_body_stmt:
 	localparam_decl;
 
 interface:
-	TOK_INTERFACE TOK_ID {
+	interface_start TOK_ID {
 		do_not_require_port_stubs = false;
 		AstNode *intf = new AstNode(AST_INTERFACE);
 		ast_stack.back()->children.push_back(intf);
@@ -522,9 +535,12 @@ interface:
 		ast_stack.pop_back();
 		log_assert(ast_stack.size() == 1);
 		current_ast_mod = NULL;
-		user_types.clear();
+		exitTypeScope();
 	};
 
+interface_start: TOK_INTERFACE	{ enterTypeScope(); }
+	;
+
 interface_body:
 	interface_body interface_body_stmt |;
 
@@ -2210,7 +2226,7 @@ behavioral_stmt:
 	} opt_arg_list ';'{
 		ast_stack.pop_back();
 	} |
-	attr TOK_BEGIN opt_label {
+	attr begin opt_label {
 		AstNode *node = new AstNode(AST_BLOCK);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
@@ -2218,6 +2234,7 @@ behavioral_stmt:
 		if ($3 != NULL)
 			node->str = *$3;
 	} behavioral_stmt_list TOK_END opt_label {
+		exitTypeScope();
 		if ($3 != NULL && $7 != NULL && *$3 != *$7)
 			frontend_verilog_yyerror("Begin label (%s) and end label (%s) don't match.", $3->c_str()+1, $7->c_str()+1);
 		if ($3 != NULL)
@@ -2301,6 +2318,9 @@ behavioral_stmt:
 		ast_stack.pop_back();
 	};
 
+begin: TOK_BEGIN	{ enterTypeScope(); }
+	;
+
 unique_case_attr:
 	/* empty */ {
 		$$ = false;
@@ -2516,12 +2536,13 @@ gen_stmt:
 		case_type_stack.pop_back();
 		ast_stack.pop_back();
 	} |
-	TOK_BEGIN opt_label {
+	begin opt_label {
 		AstNode *node = new AstNode(AST_GENBLOCK);
 		node->str = $2 ? *$2 : std::string();
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
 	} module_gen_body TOK_END opt_label {
+		exitTypeScope();
 		if ($2 != NULL)
 			delete $2;
 		if ($6 != NULL)