xorshiftHEADmaster

1 files changed, 72 insertions, 0 deletions

diff --git a/xorshift.cpp b/xorshift.cpp
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+/*
+ * Copyright 2024 Peter McGoron
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <memory>
+#include <limits>
+#include <cstdint>
+#include <iostream>
+#include <verilated.h>
+#include "Vxorshift.h"
+
+Vxorshift *mod;
+
+static void run_clock() {
+	mod->clk = !mod->clk;
+	mod->eval();
+
+	mod->clk = !mod->clk;
+	mod->eval();
+}
+
+static uint64_t xorshift_64() {
+	static uint64_t state = 88172645463325252LL;
+	state ^= state << 13;
+	state ^= state >> 7;
+	return state ^= state << 17;
+}
+
+int main(int argc, char **argv) {
+	Verilated::commandArgs(argc, argv);
+	mod = new Vxorshift;
+
+	mod->clk = 0;
+	mod->eval();
+
+	for (int i = 0; i < 100000; i++) {
+		uint64_t correct = xorshift_64();
+		run_clock();
+		if (correct != mod->data) {
+			std::cout << i << " " << correct << "!=" << mod->data << std::endl;
+		}
+	}
+
+	mod->final();
+
+	delete mod;
+
+	return 0;
+}