From 00dba4c197b7e3b6c1d1f7b90ae7b1e6172b1e5f Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Thu, 23 Feb 2017 16:33:19 +0100
Subject: [PATCH] Add support for SystemVerilog unique, unique0, and priority
 case

---
 frontends/verilog/verilog_lexer.l  |  4 ++++
 frontends/verilog/verilog_parser.y | 25 +++++++++++++++++++++----
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/frontends/verilog/verilog_lexer.l b/frontends/verilog/verilog_lexer.l
index ed33af7ba..091c1a029 100644
--- a/frontends/verilog/verilog_lexer.l
+++ b/frontends/verilog/verilog_lexer.l
@@ -171,6 +171,10 @@ YOSYS_NAMESPACE_END
 "while"        { return TOK_WHILE; }
 "repeat"       { return TOK_REPEAT; }
 
+"unique"       { SV_KEYWORD(TOK_UNIQUE); }
+"unique0"      { SV_KEYWORD(TOK_UNIQUE); }
+"priority"     { SV_KEYWORD(TOK_PRIORITY); }
+
 "always_comb"  { SV_KEYWORD(TOK_ALWAYS); }
 "always_ff"    { SV_KEYWORD(TOK_ALWAYS); }
 "always_latch" { SV_KEYWORD(TOK_ALWAYS); }
diff --git a/frontends/verilog/verilog_parser.y b/frontends/verilog/verilog_parser.y
index 7c2880e4e..9b2498694 100644
--- a/frontends/verilog/verilog_parser.y
+++ b/frontends/verilog/verilog_parser.y
@@ -117,13 +117,13 @@ static void free_attr(std::map<std::string, AstNode*> *al)
 %token TOK_POS_INDEXED TOK_NEG_INDEXED TOK_ASSERT TOK_ASSUME
 %token TOK_RESTRICT TOK_COVER TOK_PROPERTY TOK_ENUM TOK_TYPEDEF
 %token TOK_RAND TOK_CONST TOK_CHECKER TOK_ENDCHECKER
-%token TOK_INCREMENT TOK_DECREMENT
+%token TOK_INCREMENT TOK_DECREMENT TOK_UNIQUE TOK_PRIORITY
 
 %type <ast> range range_or_multirange  non_opt_range non_opt_multirange range_or_signed_int
 %type <ast> wire_type expr basic_expr concat_list rvalue lvalue lvalue_concat_list
 %type <string> opt_label tok_prim_wrapper hierarchical_id
-%type <boolean> opt_signed
-%type <al> attr
+%type <boolean> opt_signed unique_case_attr
+%type <al> attr case_attr
 
 // operator precedence from low to high
 %left OP_LOR
@@ -1167,7 +1167,7 @@ behavioral_stmt:
 		ast_stack.pop_back();
 		ast_stack.pop_back();
 	} |
-	attr case_type '(' expr ')' {
+	case_attr case_type '(' expr ')' {
 		AstNode *node = new AstNode(AST_CASE, $4);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
@@ -1177,6 +1177,23 @@ behavioral_stmt:
 		ast_stack.pop_back();
 	};
 
+unique_case_attr:
+	/* empty */ {
+		$$ = false;
+	} |
+	TOK_PRIORITY case_attr {
+		$$ = $2;
+	} |
+	TOK_UNIQUE case_attr {
+		$$ = true;
+	};
+
+case_attr:
+	attr unique_case_attr {
+		if ($2) (*$1)["\\parallel_case"] = AstNode::mkconst_int(1, false);
+		$$ = $1;
+	};
+
 case_type:
 	TOK_CASE {
 		case_type_stack.push_back(0);