module test; typedef struct packed { logic [9:-1][2:0] a; } ST1; typedef struct { ST1 st1; ST2 st2[2:0]; } ST2; typedef struct { ST2 st2; ST3 st3[2:0]; } ST3; initial begin ST3 st3; for (int i=0; i<3; i++) begin for (int j=0; j<3; j++) begin for (int k=0; k<3; k++) begin st3.st2.a[j][k] = 1'b1; end end end $display("%p", st3); end endmodule 这段代码有什么错误吗？

这段代码有一个错误，即 ST2 结构体在定义时未被正确定义。因此，编译器会报错。为了修复这个问题，需要先定义 ST2 结构体，例如：

typedef struct packed {
  logic [9:-1][2:0] a;
} ST1;

typedef struct packed {
  ST1 st1;
  logic [9:-1][2:0] b;
} ST2;

typedef struct packed {
  ST2 st2;
  logic [9:-1][2:0] c;
} ST3;

module test;
  initial begin
    ST3 st3;
    for (int i=0; i<3; i++) begin
      for (int j=0; j<3; j++) begin
        for (int k=0; k<3; k++) begin
          st3.st2.b[j][k] = 1'b1;
        end
      end
    end
    $display("%p", st3);
  end
endmodule

请注意，这里添加了 ST2 的定义，并在初始化时使用了新定义的 ST2 结构体。

相关问题

typedef struct packed { logic [9:-1][2:0] a; } ST1; typedef struct packed { ST1 st1; logic [9:-1][2:0] b; } ST2; typedef struct packed { ST2 st2; logic [9:-1][2:0] c; } ST3; module test; initial begin ST3 st3; st3 = '{ST1'{a:'h1}, '{'{a:'h1},'{a:'h0},'{a:'h1}}}; $display("%p", st3); end endmodule 这段代码有什么错误吗？如果有，应该怎么修改呢？

这段代码存在一个语法错误。在初始化 ST3 结构体变量时，应该使用大括号 {} 而不是单引号 '，并且需要在第一个大括号后添加一个 ST2 的初始化器。修改后的代码如下：

typedef struct packed {   logic [9:-1][2:0] a; } ST1;
typedef struct packed {   ST1 st1;   logic [9:-1][2:0] b; } ST2;
typedef struct packed {   ST2 st2;   logic [9:-1][2:0] c; } ST3;

module test;
  initial begin
    ST3 st3;
    st3 = '{ST2'{ST1'{a:'h1}, '{a:'h1},'{a:'h0},'{a:'h1}}, '{b:'h0}}, '{c:'h0}};
    $display("%p", st3);
  end
endmodule

这样就可以正确地初始化 ST3 变量了。

module test; typedef struct packed { logic [9:-1][2:0] a; ///REQ-EXT-10001, REQ-EXT-10004 } ST1; typedef struct packed { logic [2:0] b; } ST2; typedef struct { ST1 st1; ST2 st2[2:0]; }ST3; initial begin ST2 st2 ='{'{'{a:'h1, st1:'{'{b:'h2}}}, '{a:'h0, st1:'{'{b:'h1}}}, '{a:'h1,st1:'{'{b:h0}}}}; $display("%p", st2); end endmodule seems there is error with the initailization of st2, how should I modify the code so that it can be compiled successfully with vcs?

The initialization of st2 is incorrect. You can modify the code as follows to initialize st2 correctly:

ST2 st2[3] = '{'{3'h2}, '{3'h1}, '{3'h0}};

This initializes st2 as an array of three elements, each element being an instance of ST2 initialized with the values 3'h2, 3'h1, and 3'h0 respectively. Note that the '{' and '}' characters are used for concatenation of elements in the array.