verilator/examples/make_tracing_c/sim_main.cpp

// DESCRIPTION: Verilator: Verilog example module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2017 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0
//======================================================================

// Include common routines
#include <verilated.h>

// Include model header, generated from Verilating "top.v"
#include "Vtop.h"

// Current simulation time (64-bit unsigned)
vluint64_t main_time = 0;
// Called by $time in Verilog
double sc_time_stamp() {
    return main_time;  // Note does conversion to real, to match SystemC
}

int main(int argc, char** argv, char** env) {
    // This is a more complicated example, please also see the simpler examples/make_hello_c.

    // Prevent unused variable warnings
    if (false && argc && argv && env) {}

    // Set debug level, 0 is off, 9 is highest presently used
    // May be overridden by commandArgs
    Verilated::debug(0);

    // Randomization reset policy
    // May be overridden by commandArgs
    Verilated::randReset(2);

    // Verilator must compute traced signals
    Verilated::traceEverOn(true);

    // Pass arguments so Verilated code can see them, e.g. $value$plusargs
    // This needs to be called before you create any model
    Verilated::commandArgs(argc, argv);

    // Create logs/ directory in case we have traces to put under it
    Verilated::mkdir("logs");

    // Construct the Verilated model, from Vtop.h generated from Verilating "top.v"
    Vtop* top = new Vtop;  // Or use a const unique_ptr, or the VL_UNIQUE_PTR wrapper

    // Set some inputs
    top->reset_l = !0;
    top->clk = 0;
    top->in_small = 1;
    top->in_quad = 0x1234;
    top->in_wide[0] = 0x11111111;
    top->in_wide[1] = 0x22222222;
    top->in_wide[2] = 0x3;

    // Simulate until $finish
    while (!Verilated::gotFinish()) {
        main_time++;  // Time passes...

        // Toggle a fast (time/2 period) clock
        top->clk = !top->clk;

        // Toggle control signals on an edge that doesn't correspond
        // to where the controls are sampled; in this example we do
        // this only on a negedge of clk, because we know
        // reset is not sampled there.
        if (!top->clk) {
            if (main_time > 1 && main_time < 10) {
                top->reset_l = !1;  // Assert reset
            } else {
                top->reset_l = !0;  // Deassert reset
            }
            // Assign some other inputs
            top->in_quad += 0x12;
        }

        // Evaluate model
        // (If you have multiple models being simulated in the same
        // timestep then instead of eval(), call eval_step() on each, then
        // eval_end_step() on each.)
        top->eval();

        // Read outputs
        VL_PRINTF("[%" VL_PRI64 "d] clk=%x rstl=%x iquad=%" VL_PRI64 "x"
                  " -> oquad=%" VL_PRI64 "x owide=%x_%08x_%08x\n",
                  main_time, top->clk, top->reset_l, top->in_quad, top->out_quad, top->out_wide[2],
                  top->out_wide[1], top->out_wide[0]);
    }

    // Final model cleanup
    top->final();

    //  Coverage analysis (since test passed)
#if VM_COVERAGE
    Verilated::mkdir("logs");
    VerilatedCov::write("logs/coverage.dat");
#endif

    // Destroy model
    delete top;
    top = nullptr;

    // Fin
    exit(0);
}