To accurately express the requirement that gnt follow req a property is required: property req_gnt; @(posedge clk) req |=> gnt; endproperty assert_req_gnt: assert property (req_gnt) else $error("req not followed by gnt."); This example shows an implication operator |=>.
gnt に続いて req が High になるということを正確に表現するには属性表明が必要となる: property req_gnt; @(posedge clk) req |=> gnt; endproperty assert_req_gnt: assert property (req_gnt) else $error("req not followed by gnt."); この例では含意演算子 |=> を使っている。