I have some verilog VPI code that I'm porting to use SystemVerilog DPI, to be run in Modelsim and Verilator.
In VPI, I use vpi_printf() for debugging and status information. This doesn't work when running the DPI in Verilator. Should I just be using regular printf() instead?
(This feels like it ought to be a simple question, but good SystemVerilog examples seem to be scarce)
DPI doesn't have special print commands. You can use regular C printf() or std::cout << "Your Message Here" << std::end. Some reasonable tutorials can be found with your preferred search engine with [systemverilog dpi] as your search term.
If you want to be lazy, you can keep #include <vpi_user.h> in your DPI files to keep using vpi_printf()
Alternatively, have your DPI call a SV function. With this method, adding the simulator's time-stamp is possible. Example:
my_sv.sv:
// ...
export "DPI-C" function dpi_print;
function void dpi_print(input string msg);
$display("%t :: %s", $time, msg);
endfunction : dpi_print
// ...
my_dpi.c :
#include <stdlib.h>
#include <stdio.h>
#include "svdpi.h"
...
extern dpi_print(const char* msg);
....
int some_c_func( /* ... */ ) {
// ...
dpi_print("message");
// ...
}
