摘要：
The keep attribute is used for a wire or net node. For example:In Verilog:wire my_wire /* synthesis keep = 1 */:In VHDL:signal my_signal: bit;attribute syn_keep : boolean;attribute syn_keep of my_signal: signal is true;The preserve attribute is used for a register. For example:In Verilog:reg my_reg 阅读全文