Various fixes for correct parameter support

frontends/ast/ast.cc

@@ -814,8 +814,8 @@ RTLIL::IdString AstModule::derive(RTLIL::Design *design, std::map<RTLIL::IdStrin
 			log("Parameter %s = %s\n", child->str.c_str(), log_signal(RTLIL::SigSpec(parameters[child->str])));
 	rewrite_parameter:
 			para_info += stringf("%s=%s", child->str.c_str(), log_signal(RTLIL::SigSpec(parameters[para_id])));
-			child->delete_children();
+			delete child->children.at(0);
-			child->children.push_back(AstNode::mkconst_bits(parameters[para_id].bits, false));
+			child->children[0] = AstNode::mkconst_bits(parameters[para_id].bits, child->is_signed);
 			hash_data.insert(hash_data.end(), child->str.begin(), child->str.end());
 			hash_data.push_back(0);
 			hash_data.insert(hash_data.end(), parameters[para_id].bits.begin(), parameters[para_id].bits.end());

frontends/ast/genrtlil.cc

@@ -562,6 +562,7 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint)
 	int sub_width_hint = -1;
 	int this_width = 0;
 	AstNode *range = NULL;
+	AstNode *id_ast = NULL;
 
 	switch (type)
 	{
@@ -572,15 +573,24 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint)
 		break;
 
 	case AST_IDENTIFIER:
-		if (!id2ast)
+		id_ast = id2ast;
+		if (id_ast == NULL && current_scope.count(str))
+			id_ast = current_scope.at(str);
+		if (!id_ast)
 			log_error("Failed to resolve identifier %s for width detection at %s:%d!\n", str.c_str(), filename.c_str(), linenum);
-		if ((id2ast->type == AST_PARAMETER || id2ast->type == AST_LOCALPARAM) && id2ast->children[0]->type == AST_CONSTANT) {
+		if (id_ast->type == AST_PARAMETER || id_ast->type == AST_LOCALPARAM) {
-			this_width = id2ast->children[0]->bits.size();
+			if (id_ast->children.size() > 1 && id_ast->children[1]->range_valid) {
+				this_width = id_ast->children[1]->range_left - id_ast->children[1]->range_right + 1;
+			} else
+			if (id_ast->children[0]->type == AST_CONSTANT) {
+				this_width = id_ast->children[0]->bits.size();
+			} else
+				log_error("Failed to detect width for parameter %s at %s:%d!\n", str.c_str(), filename.c_str(), linenum);
 			if (children.size() != 0)
 				range = children[0];
-		} else if (id2ast->type == AST_WIRE || id2ast->type == AST_AUTOWIRE) {
+		} else if (id_ast->type == AST_WIRE || id_ast->type == AST_AUTOWIRE) {
-			if (!id2ast->range_valid) {
+			if (!id_ast->range_valid) {
-				if (id2ast->type == AST_AUTOWIRE)
+				if (id_ast->type == AST_AUTOWIRE)
 					this_width = 1;
 				else {
 					current_ast_mod->dumpAst(stdout, "");
@@ -590,16 +600,16 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint)
 					log_error("Failed to detect with of signal access `%s' at %s:%d!\n", str.c_str(), filename.c_str(), linenum);
 				}
 			} else {
-				this_width = id2ast->range_left - id2ast->range_right + 1;
+				this_width = id_ast->range_left - id_ast->range_right + 1;
 				if (children.size() != 0)
 					range = children[0];
 			}
-		} else if (id2ast->type == AST_GENVAR) {
+		} else if (id_ast->type == AST_GENVAR) {
 			this_width = 32;
-		} else if (id2ast->type == AST_MEMORY) {
+		} else if (id_ast->type == AST_MEMORY) {
-			if (!id2ast->children[0]->range_valid)
+			if (!id_ast->children[0]->range_valid)
 				log_error("Failed to detect with of memory access `%s' at %s:%d!\n", str.c_str(), filename.c_str(), linenum);
-			this_width = id2ast->children[0]->range_left - id2ast->children[0]->range_right + 1;
+			this_width = id_ast->children[0]->range_left - id_ast->children[0]->range_right + 1;
 		} else
 			log_error("Failed to detect width for identifier %s at %s:%d!\n", str.c_str(), filename.c_str(), linenum);
 		if (range) {
@@ -620,7 +630,7 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint)
 				this_width = range->range_left - range->range_right + 1;
 		} else
 			width_hint = std::max(width_hint, this_width);
-		if (!id2ast->is_signed)
+		if (!id_ast->is_signed)
 			sign_hint = false;
 		break;
 

frontends/ast/simplify.cc

@@ -197,6 +197,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		child_0_is_self_determined = true;
 		break;
 
+	case AST_PARAMETER:
+	case AST_LOCALPARAM:
+		children[0]->detectSignWidth(width_hint, sign_hint);
+		if (children.size() > 1) {
+			assert(children[1]->type == AST_RANGE);
+			while (children[1]->simplify(false, false, false, stage, -1, false) == true) { }
+			if (!children[1]->range_valid)
+				log_error("Non-constant width range on parameter decl at %s:%d.\n", filename.c_str(), linenum);
+			width_hint = std::max(width_hint, children[1]->range_left - children[1]->range_right + 1);
+		}
+		break;
+
 	case AST_TO_SIGNED:
 	case AST_TO_UNSIGNED:
 	case AST_CONCAT:
@@ -419,6 +431,19 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		}
 	}
 
+	// trim/extend parameters
+	if ((type == AST_PARAMETER || type == AST_LOCALPARAM) && children[0]->type == AST_CONSTANT && children.size() > 1) {
+		if (!children[1]->range_valid)
+			log_error("Non-constant width range on parameter decl at %s:%d.\n", filename.c_str(), linenum);
+		int width = children[1]->range_left - children[1]->range_right + 1;
+		if (width != int(children[0]->bits.size())) {
+			RTLIL::SigSpec sig(children[0]->bits);
+			sig.extend(width, children[0]->is_signed);
+			delete children[0];
+			children[0] = mkconst_bits(sig.as_const().bits, children[0]->is_signed);
+		}
+	}
+
 	// annotate identifiers using scope resolution and create auto-wires as needed
 	if (type == AST_IDENTIFIER) {
 		if (current_scope.count(str) == 0) {

frontends/verilog/parser.y

@@ -225,10 +225,18 @@ module_para_opt:
 	'#' '(' module_para_list ')' | /* empty */;
 
 module_para_list:
-	TOK_PARAMETER single_param_decl |
+	single_module_para |
-	TOK_PARAMETER single_param_decl ',' module_para_list |
+	single_module_para ',' module_para_list |
 	/* empty */;
 
+single_module_para:
+	TOK_PARAMETER {
+		astbuf1 = new AstNode(AST_PARAMETER);
+		astbuf1->children.push_back(AstNode::mkconst_int(0, true));
+	} param_signed param_integer param_range single_param_decl {
+		delete astbuf1;
+	};
+
 module_args_opt:
 	'(' ')' | /* empty */ | '(' module_args optional_comma ')';
 
@@ -368,38 +376,56 @@ task_func_body:
 	task_func_body behavioral_stmt |
 	/* empty */;
 
+param_signed:
+	TOK_SIGNED {
+		astbuf1->is_signed = true;
+	} | /* empty */;
+
+param_integer:
+	TOK_INTEGER {
+		if (astbuf1->children.size() != 1)
+			frontend_verilog_yyerror("Syntax error.");
+		astbuf1->children.push_back(new AstNode(AST_RANGE));
+		astbuf1->children[0]->children.push_back(AstNode::mkconst_int(31, true));
+		astbuf1->children[0]->children.push_back(AstNode::mkconst_int(0, true));
+	} | /* empty */;
+
+param_range:
+	range {
+		if ($1 != NULL) {
+			if (astbuf1->children.size() != 1)
+				frontend_verilog_yyerror("Syntax error.");
+			astbuf1->children.push_back($1);
+		}
+	};
+
 param_decl:
-	TOK_PARAMETER param_decl_list ';';
+	TOK_PARAMETER {
+		astbuf1 = new AstNode(AST_PARAMETER);
+		astbuf1->children.push_back(AstNode::mkconst_int(0, true));
+	} param_signed param_integer param_range param_decl_list ';' {
+		delete astbuf1;
+	};
+
+localparam_decl:
+	TOK_LOCALPARAM {
+		astbuf1 = new AstNode(AST_LOCALPARAM);
+		astbuf1->children.push_back(AstNode::mkconst_int(0, true));
+	} param_signed param_integer param_range param_decl_list ';' {
+		delete astbuf1;
+	};
 
 param_decl_list:
 	single_param_decl | param_decl_list ',' single_param_decl;
 
 single_param_decl:
-	range TOK_ID '=' expr {
+	TOK_ID '=' expr {
-		AstNode *node = new AstNode(AST_PARAMETER);
+		AstNode *node = astbuf1->clone();
-		node->str = *$2;
+		node->str = *$1;
-		node->children.push_back($4);
+		delete node->children[0];
-		if ($1 != NULL)
+		node->children[0] = $3;
-			node->children.push_back($1);
 		ast_stack.back()->children.push_back(node);
-		delete $2;
+		delete $1;
-	};
-
-localparam_decl:
-	TOK_LOCALPARAM localparam_decl_list ';';
-
-localparam_decl_list:
-	single_localparam_decl | localparam_decl_list ',' single_localparam_decl;
-
-single_localparam_decl:
-	range TOK_ID '=' expr {
-		AstNode *node = new AstNode(AST_LOCALPARAM);
-		node->str = *$2;
-		node->children.push_back($4);
-		if ($1 != NULL)
-			node->children.push_back($1);
-		ast_stack.back()->children.push_back(node);
-		delete $2;
 	};
 
 defparam_decl: