Fixed handling of parameters and const functions in casex/casez pattern

frontends/ast/ast.cc

@@ -146,6 +146,8 @@ std::string AST::type2str(AstNodeType type)
 	X(AST_ASSIGN_LE)
 	X(AST_CASE)
 	X(AST_COND)
+	X(AST_CONDX)
+	X(AST_CONDZ)
 	X(AST_DEFAULT)
 	X(AST_FOR)
 	X(AST_WHILE)
@@ -501,7 +503,12 @@ void AstNode::dumpVlog(FILE *f, std::string indent)
 		break;
 
 	case AST_CASE:
-		fprintf(f, "%s" "case (", indent.c_str());
+		if (!children.empty() && children[0]->type == AST_CONDX)
+			fprintf(f, "%s" "casex (", indent.c_str());
+		else if (!children.empty() && children[0]->type == AST_CONDZ)
+			fprintf(f, "%s" "casez (", indent.c_str());
+		else
+			fprintf(f, "%s" "case (", indent.c_str());
 		children[0]->dumpVlog(f, "");
 		fprintf(f, ")\n");
 		for (size_t i = 1; i < children.size(); i++) {
@@ -512,6 +519,8 @@ void AstNode::dumpVlog(FILE *f, std::string indent)
 		break;
 
 	case AST_COND:
+	case AST_CONDX:
+	case AST_CONDZ:
 		for (auto child : children) {
 			if (child->type == AST_BLOCK) {
 				fprintf(f, ":\n");

frontends/ast/ast.h

@@ -122,6 +122,8 @@ namespace AST
 		AST_ASSIGN_LE,
 		AST_CASE,
 		AST_COND,
+		AST_CONDX,
+		AST_CONDZ,
 		AST_DEFAULT,
 		AST_FOR,
 		AST_WHILE,

frontends/ast/genrtlil.cc

@@ -338,12 +338,14 @@ struct AST_INTERNAL::ProcessGenerator
 		case AST_CASE:
 			for (auto child : ast->children)
 				if (child != ast->children[0]) {
-					log_assert(child->type == AST_COND);
+					log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 					collect_lvalues(reg, child, type_eq, type_le, false);
 				}
 			break;
 
 		case AST_COND:
+		case AST_CONDX:
+		case AST_CONDZ:
 		case AST_ALWAYS:
 		case AST_INITIAL:
 			for (auto child : ast->children)
@@ -467,7 +469,7 @@ struct AST_INTERNAL::ProcessGenerator
 				{
 					if (child == ast->children[0])
 						continue;
-					log_assert(child->type == AST_COND);
+					log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 
 					subst_lvalue_map.save();
 					subst_rvalue_map.save();

frontends/ast/simplify.cc

@@ -540,6 +540,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		}
 	}
 
+	if (type == AST_CONDX && children.size() > 0 && children.at(0)->type == AST_CONSTANT) {
+		for (auto &bit : children.at(0)->bits)
+			if (bit == State::Sz || bit == State::Sx)
+				bit = State::Sa;
+	}
+
+	if (type == AST_CONDZ && children.size() > 0 && children.at(0)->type == AST_CONSTANT) {
+		for (auto &bit : children.at(0)->bits)
+			if (bit == State::Sz)
+				bit = State::Sa;
+	}
+
 	if (const_fold && type == AST_CASE)
 	{
 		while (children[0]->simplify(const_fold, at_zero, in_lvalue, stage, width_hint, sign_hint, in_param)) { }
@@ -548,7 +560,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 			new_children.push_back(children[0]);
 			for (int i = 1; i < GetSize(children); i++) {
 				AstNode *child = children[i];
-				log_assert(child->type == AST_COND);
+				log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 				for (auto v : child->children) {
 					if (v->type == AST_DEFAULT)
 						goto keep_const_cond;
@@ -1125,7 +1137,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		AstNode *selected_case = NULL;
 		for (size_t i = 1; i < children.size(); i++)
 		{
-			log_assert(children.at(i)->type == AST_COND);
+			log_assert(children.at(i)->type == AST_COND || children.at(i)->type == AST_CONDX || children.at(i)->type == AST_CONDZ);
 
 			AstNode *this_genblock = NULL;
 			for (auto child : children.at(i)->children) {
@@ -2984,7 +2996,7 @@ AstNode *AstNode::eval_const_function(AstNode *fcall)
 			for (size_t i = 1; i < stmt->children.size(); i++)
 			{
 				bool found_match = false;
-				log_assert(stmt->children.at(i)->type == AST_COND);
+				log_assert(stmt->children.at(i)->type == AST_COND || stmt->children.at(i)->type == AST_CONDX || stmt->children.at(i)->type == AST_CONDZ);
 
 				if (stmt->children.at(i)->children.front()->type == AST_DEFAULT) {
 					sel_case = stmt->children.at(i)->children.back();

frontends/verilog/verilog_parser.y

@@ -1094,7 +1094,9 @@ case_body:
 
 case_item:
 	{
-		AstNode *node = new AstNode(AST_COND);
+		AstNode *node = new AstNode(
+				case_type_stack.size() && case_type_stack.back() == 'x' ? AST_CONDX :
+				case_type_stack.size() && case_type_stack.back() == 'z' ? AST_CONDZ : AST_COND);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
 	} case_select {
@@ -1114,7 +1116,9 @@ gen_case_body:
 
 gen_case_item:
 	{
-		AstNode *node = new AstNode(AST_COND);
+		AstNode *node = new AstNode(
+				case_type_stack.size() && case_type_stack.back() == 'x' ? AST_CONDX :
+				case_type_stack.size() && case_type_stack.back() == 'z' ? AST_CONDZ : AST_COND);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
 	} case_select {