undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com Patches, unit tests, benchmarks, whitepaper, and outreach briefs. Public domain — no copyright claimed. Use freely.
2026-03-26 17:11:57 -04:00 · 2026-03-26 17:11:57 -04:00 · 0a580b313d
commit 0a580b313d
70422 changed files with 17213626 additions and 0 deletions
--- a/test/jdk/java/math/BigInteger/BigIntegerParallelMultiplyTest.java
+++ b/test/jdk/java/math/BigInteger/BigIntegerParallelMultiplyTest.java
@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 1998, 2020, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @run main BigIntegerParallelMultiplyTest
+ * @summary tests parallelMultiply() method in BigInteger
+ * @author Heinz Kabutz heinz@javaspecialists.eu
+ */
+
+import java.math.BigInteger;
+import java.util.function.BinaryOperator;
+
+/**
+ * This is a simple test class created to ensure that the results
+ * of multiply() are the same as multiplyParallel(). We calculate
+ * the Fibonacci numbers using Dijkstra's sum of squares to get
+ * very large numbers (hundreds of thousands of bits).
+ *
+ * @author Heinz Kabutz, heinz@javaspecialists.eu
+ */
+public class BigIntegerParallelMultiplyTest {
+    public static BigInteger fibonacci(int n, BinaryOperator<BigInteger> multiplyOperator) {
+        if (n == 0) return BigInteger.ZERO;
+        if (n == 1) return BigInteger.ONE;
+
+        int half = (n + 1) / 2;
+        BigInteger f0 = fibonacci(half - 1, multiplyOperator);
+        BigInteger f1 = fibonacci(half, multiplyOperator);
+        if (n % 2 == 1) {
+            BigInteger b0 = multiplyOperator.apply(f0, f0);
+            BigInteger b1 = multiplyOperator.apply(f1, f1);
+            return b0.add(b1);
+        } else {
+            BigInteger b0 = f0.shiftLeft(1).add(f1);
+            return multiplyOperator.apply(b0, f1);
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+        compare(1000, 324);
+        compare(10_000, 3473);
+        compare(100_000, 34883);
+        compare(1_000_000, 347084);
+    }
+
+    private static void compare(int n, int expectedBitCount) {
+        BigInteger multiplyResult = fibonacci(n, BigInteger::multiply);
+        BigInteger parallelMultiplyResult = fibonacci(n, BigInteger::parallelMultiply);
+        checkBitCount(n, expectedBitCount, multiplyResult);
+        checkBitCount(n, expectedBitCount, parallelMultiplyResult);
+        if (!multiplyResult.equals(parallelMultiplyResult))
+            throw new AssertionError("multiply() and parallelMultiply() give different results");
+    }
+
+    private static void checkBitCount(int n, int expectedBitCount, BigInteger number) {
+        if (number.bitCount() != expectedBitCount)
+            throw new AssertionError(
+                    "bitCount of fibonacci(" + n + ") was expected to be " + expectedBitCount
+                            + " but was " + number.bitCount());
+    }
+}