Add VerilatedContext::useNumaAssign and set on threads() call (#6954)

test_regress/t/t_gantt_numa_default_threads.cpp

@@ -0,0 +1,53 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+//
+// Copyright 2026 by Wilson Snyder. 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
+//
+//*************************************************************************
+
+// Generated header
+#include "Vt_gantt_numa_default_threads.h"
+// General headers
+#include "verilated.h"
+
+#include "TestCheck.h"
+
+int errors = 0;
+
+std::unique_ptr<Vt_gantt_numa_default_threads> topp;
+
+int main(int argc, char** argv) {
+    vluint64_t sim_time = 1100;
+    const std::unique_ptr<VerilatedContext> contextp{new VerilatedContext};
+    contextp->debug(0);
+    contextp->commandArgs(argc, argv);
+    srand48(5);
+    TEST_CHECK_EQ(contextp->useNumaAssign(), false);
+    contextp->threads(3);
+    TEST_CHECK_EQ(contextp->useNumaAssign(), true);
+    contextp->useNumaAssign(false);
+    TEST_CHECK_EQ(contextp->useNumaAssign(), false);
+    topp.reset(new VM_PREFIX{"top"});
+
+    topp->clk = 0;
+    topp->eval();
+    { contextp->timeInc(10); }
+
+    while ((contextp->time() < sim_time) && !contextp->gotFinish()) {
+        topp->eval();
+        topp->clk = !topp->clk;
+        topp->eval();
+        contextp->timeInc(5);
+    }
+    if (!contextp->gotFinish()) {
+        vl_fatal(__FILE__, __LINE__, "main", "%Error: Timeout; never got a $finish");
+    }
+    topp->final();
+
+    topp.reset();
+    return (errors ? 10 : 0);
+}

test_regress/t/t_gantt_numa_default_threads.py

@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2026 by Wilson Snyder. 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
+
+import os
+import sys
+import vltest_bootstrap
+
+test.scenarios('vltmt')
+
+test.top_filename = "t/t_gantt.v"
+test.pli_filename = "t/t_gantt_numa_default_threads.cpp"
+
+# Require enough cores so default thread count stays >= model threads
+# (we don't call contextp->threads in this test)
+test.skip_if_too_few_cores()
+
+test.compile(
+    make_main=False,
+    verilator_flags2=[
+        "--prof-exec",
+        "--exe",
+        test.pli_filename,
+        test.t_dir + "/t_gantt_c.cpp",
+    ],
+    threads=test.get_default_vltmt_threads,
+)
+
+test.execute(all_run_flags=[
+    "+verilator+prof+exec+start+2",
+    " +verilator+prof+exec+window+2",
+    " +verilator+prof+exec+file+" + test.obj_dir + "/profile_exec.dat",
+])
+
+gantt_log = test.obj_dir + "/gantt_default_threads.log"
+test.run(cmd=[
+    os.environ["VERILATOR_ROOT"] + "/bin/verilator_gantt",
+    "--no-vcd",
+    test.obj_dir + "/profile_exec.dat",
+    "| tee " + gantt_log,
+])
+
+if sys.platform != "darwin":
+    test.file_grep(gantt_log, r"NUMA status += NUMA assignment not requested")
+
+test.passes()