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EXPORT

Export Methods

Methods implemented in SystemVerilog and specified in export declarations can be called from C, such methods are referred to as exported methods.

Steps To Write Export Methods

In SV Code :

Setp1: Export the systemverilog function

export "DPI-C" function export_func;

Step2: Define the systemverilog function

  function void export_func();
      $display("SV: Hello from SV ");
  endfunction

In C code :

Step3: Export the Systemverilog function

extern void export_func(void);

Step4: Invoke the systemverilog function

   void import_func()
   {
       export_func();
   }

Full Example:

CODE: SV_file.sv
    program main;

        export "DPI-C" function export_func;
        import "DPI-C" function void import_func();

        function void export_func();
             $display("SV: Hello from SV ");
        endfunction

        initial
        begin
           import_func();
        end

    endprogram

CODE: C_file.c
    #include "stdio.h"
    #include "vc_hdrs.h"
    #include "svdpi.h"

    extern void export_func(void);

    void import_func()
    {
          export_func();
    }

RESULTS:

SV: Hello from SV

Blocking Export Dpi Task

SV Dpi allows C to call a SystemVerilog method which consumes time.

CODE:SV_file.sv
     program main;

         export "DPI-C" task export_task;
         import "DPI-C" context task import_task();

         task export_task();
             $display("SV: Entered the export function . wait for some time : %0d ",$time);
             #100;
             $display("SV: After waiting %0d",$time);
         endtask

         initial
         begin
            $display("SV: Before calling import function %0d",$time);
            import_task();
            $display("SV: After  calling import function %0d",$time);
         end

     endprogram
CODE: C_file.c
    extern void export_task();

    void import_task()
    {
        printf(" C: Before calling export function\n");
        export_task();
        printf(" C: After  calling export function\n");
    }
RESULTS

SV: Before calling import function 0
C: Before calling export function
SV: Entered the export function . wait for some time : 0
SV: After waiting 100
C: After  calling export function
SV: After  calling import function 100

Index
Introductions
Layers
Import
Naming
Export
Pure And Context
Data Types
Arrays
Passing Structs And Unions
Arguments Type
Disablie

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