[#72179] add wip example for SAIF trace

examples/saif_example/counter.v

@@ -0,0 +1,51 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// Copyright 2025 by Antmicro. This program is free software; you can
+// redistribute it and/or modify it under the terms of either the GNU
+// Lesser General Public License Version 3 or the Perl Artistic License
+// Version 2.0.
+// SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+module t (
+	 // Outputs
+	 state,
+	 // Inputs
+	 clk);
+
+    input clk;
+    reg rst;
+    output [7:0] state;
+
+	 counter c0 (
+        .clk (clk),
+        .rst (rst),
+	     .out (state));
+
+    int cyc;
+
+    always @ (posedge clk) begin
+        cyc <= cyc + 1;
+        if (cyc == 0) begin
+            rst <= 1;
+        end
+        else if (cyc == 10) begin
+            rst <= 0;
+        end
+        else if (cyc == 11) begin
+            rst <= 1;
+        end
+    end
+endmodule
+
+module counter (
+	 input clk,
+	 input rst,
+	 output reg[7:0] out);
+
+	 always @ (posedge clk) begin
+		  if (!rst)
+			   out <= 0;
+		  else
+			   out <= out + 1;
+	 end
+endmodule

examples/saif_example/saif_trace.cpp

@@ -0,0 +1,55 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2025 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+#include <verilated.h>
+#include <verilated_saif_c.h>
+
+#include <memory>
+
+#include "Vcounter.h"
+
+int errors = 0;
+
+unsigned long long main_time = 0;
+double sc_time_stamp() { return static_cast<double>(main_time); }
+
+const char* trace_name() {
+    static char name[1000];
+    VL_SNPRINTF(name, 1000, "simx.saif");
+    return name;
+}
+
+int main(int argc, char** argv) {
+    Verilated::debug(0);
+    Verilated::traceEverOn(true);
+    Verilated::commandArgs(argc, argv);
+
+    std::unique_ptr<Vcounter> top{new Vcounter};
+
+    std::unique_ptr<VerilatedSaifC> tfp{new VerilatedSaifC};
+
+    static constexpr int SIMULATION_DURATION{199};
+    top->trace(tfp.get(), SIMULATION_DURATION);
+
+    tfp->open(trace_name());
+
+    top->clk = 0;
+
+    while (main_time < SIMULATION_DURATION) {
+        top->clk = !top->clk;
+        top->eval();
+        tfp->dump(static_cast<unsigned int>(main_time));
+        ++main_time;
+    }
+    tfp->close();
+    top->final();
+    tfp.reset();
+    top.reset();
+    printf("*-* All Finished *-*\n");
+    return errors;
+}