integer atom explicit sign cast support

test/basic/cast.sv

@@ -33,4 +33,12 @@ module top;
         $display("%b", 5'(1'sb1));
     end
 
+    parameter W = 9;
+    initial begin
+        byte i = -1;
+        byte unsigned j = -1;
+        $display("%b", W'(i));
+        $display("%b", W'(j));
+    end
+
 endmodule

test/basic/cast.v

@@ -36,4 +36,18 @@ module top;
         $display("%b", 5'sb11111);
     end
 
+    parameter W = 9;
+    initial begin : block
+        reg signed [7:0] i;
+        reg [7:0] j;
+        reg [8:0] i_extended;
+        reg [8:0] j_extended;
+        i = -1;
+        j = -1;
+        i_extended = i;
+        j_extended = j;
+        $display("%b", i_extended);
+        $display("%b", j_extended);
+    end
+
 endmodule

test/lib/functions.sh

@@ -66,7 +66,7 @@ assertConverts() {
     assertFalse "conversion of $ac_file still contains dimension queries" $?
     echo "$filtered" | egrep "\s(int\|bit\|logic\|byte\|struct\|enum\|longint\|shortint)\s"
     assertFalse "conversion of $ac_file still contains SV types" $?
-    echo "$filtered" | grep "[^$]unsigned" > /dev/null
+    echo "$filtered" | grep "[^\$a-zA-Z_]unsigned" > /dev/null
     assertFalse "conversion of $ac_file still contains unsigned keyword" $?
 }