当明确知道存在优先级或者不存在优先级逻辑的情况下,应当使用SystemVerilog中的priority和unique关键字。使用这些关键字有利于传达设计意图,指导综合工具获得正确的结果。但是使用上述关键字并不能保证删除不必要的latch。在case语句中,如果存在case选项丢失,则仍然可能存在latch,避免这些latch的最简单的方式是在case语句之前...
SystemVerilog 拥有unique关键字和priority关键字,旨在解决上述问题。 SystemVerilog中的unique和priority关键字修饰符放在if,case,casez,casex语句之前,如下所示: 代码语言:javascript 复制 uniqueif(expression)statementselsestatements prioritycase(case_expression)case_item_1:case_expression_1case_item_2:case_expression...
在Verilog中,代码不规范的case语句经常会导致意外的综合优化或意外的latch。如果未在硅前仿真或门级仿真中发现这些问题,则很容易导致芯片无法正常工作。SystemVerilog 拥有unique关键字和priority关键字,旨在解决上述问题。SystemVerilog中的unique和priority关键字修饰符放在if,case,casez,casex语句之前,如下所示: unique if...
SystemVerilog拥有unique关键字和priority关键字,旨在解决上述问题。 SystemVerilog中的unique和priority关键字修饰符放在if,case,casez,casex语句之前,如下所示: unique if (expression) statements else statements priority case (case_expression) case_item_1: case_expression_1 case_item_2: case_expression_2 endc...
SystemVerilog 'unique' and 'priority' if-else 条件语句用于决定是否执行语句。if else SystemVerilog 引入了一下用于违规检查的构造。if else unique-if unique0-if priority-if unique-if, unique0-if unique-if按任意顺序评估条件,并执行以下操作:
A SystemVerilog case statement checks whether an expression matches one of a number of expressions and branches appropriately. The behavior is the same as in Verilog. Click here to learn about Verilog case statements ! unique,unique0 case All case stat
Improperly coded Verilogcasestatements can frequently cause unintended synthesis optimizations or unintended latches. These problems, if not caught in pre-silicon simulations or gate level simulations, can easily lead to a non-functional chip. The new SystemVeriloguniqueandprioritykeywords are designed to...
SystemVerilog's priority & unique - A Solution to Verilog's "full_case" & "parallel_case" Evil Twins! Clifford E. Cummings Sunburst Design, Inc. ABSTRACT At Boston SNUG 1999, I introduced the evil twins of Verilog synthesis, "full_case" and "parallel_case.[2]" In the 1999 Boston ...
Clifford Cummings
SystemVerilog Unique And Priority – How Do I Use Them? September 19, 2015 by Jason Yu Improperly coded Verilog case statements can frequently cause unintended synthesis optimizations or unintended latches. These problems, if not caught in pre-silicon simulations or gate level simulations, can ...