minor update

hw/rtl/cache/VX_cache_bank.sv

@@ -257,6 +257,7 @@ module VX_cache_bank #(
     if (UUID_WIDTH != 0) begin
         assign flush_tag = {flush_uuid, (TAG_WIDTH-UUID_WIDTH)'(1'b0)};
     end else begin
+        `UNUSED_VAR (flush_uuid)
         assign flush_tag = '0;
     end
 

hw/rtl/core/VX_decode.sv

@@ -152,7 +152,7 @@ module VX_decode import VX_gpu_pkg::*; #(
 
     always @(*) begin
 
-        ex_type   = '0;
+        ex_type   = 'x;
         op_type   = 'x;
         op_args   = 'x;
         rd_v      = '0;