其中元素在数组中的索引是连续的,但是如果要实现数组元素访问时不采用连续索引的话,采用动态数组和定宽数组就不是很合适,容易造成空间的浪费,为此在SystemVerilog中引入了关联数组(Associative Array),实现了一种查找表,该查找表的索引可以根据用户需要指定,不限于整形,其内存空间直到使用时才会分配,即只针对写入的元素...
关联数组的声明语法是:data_type array_id [index_type];其中data_type确定数组元素的类型,array_id是数组的名字,index_type是索引的类型。至于数组的使用,建议使用foreach进行循环遍历,它会自动遍历到已经存在的那些元素;还可以使用关联数组的delete、first、exists等内建方法。 有一个地方需要注意,当你通过一个不...
Creating a Dynamic Array of Associative Arrays 关联数组也可以是动态数组中的元素,如下示例: module assoc_arr; //Create a dynamic array whose elements are associative arrays int games [ ] [string]; initial begin //Create a dynamic array with size of 3 elements games = new [3]; //Initialize ...
int map[ string ]; map[ "hello" ] = 1; map[ "sad" ] = 2; map[ "world" ] = 3; map.delete( "sad" ); // remove entry whose index is "sad" from "map" map.delete; // remove all entries from the associative array "map" 1. 2. 3. 4. 5. 6. 7. 3.关联数组Exists() ...
// Lower Performance Version// Associative array declaration - no default value:intaa[int];if(aa.exists(i)) begin lookup = aa[i]; end// Higher Performance Version// Associative array declaration - setting the default to 0intaa[int] = {default:0}; ...
array$display("fruits_10.num() = %0d", fruits_10.num());// exists() : Check if a particular key exists in this dynamic arrayif(fruits_10.exists("orange"))$display("Found %0d orange !", fruits_10["orange"]);if(fruits_10.exists("apricots"))$display("Sorry, season for ...
array$display("fruits_l0.num() = %0d",fruits_l0.num());// exists() : Check if a particular key exists in this dynamic arrayif(fruits_l0.exists("orange"))$display("Found %0d orange !",fruits_l0["orange"]);if(!fruits_l0.exists("apricots"))$display("Sorry, season for ...
Sometimes, it is useful to create a class without intending to create any objects of the class. The class exists simply as a base class from which other classes can be derived. In SystemVerilog this is called an abstract class and is declared by using the word virtual: ...
⼀个packed array被表⽰为⼀个连续的位集合。数组⼤⼩定义的格式必须是[msb:lsb]，⽽不是[size]。例如：bit[2:0] [7:0] array5;在存储时是连续的：1.3 Unpacked array 很多SystemVerilog仿真器在存放数组元素时使⽤32bit的字边界，所以byte，shortint和int都是存放在⼀个字中，⽽longint则...
Automatic - exists for the duration of a block activation Dynamic - class object memory management by active references. Queues, dynamic arrays, and associative array add another dimension to the above for each element. The problem is when you pass variable by reference, yo...