hotspot/test/compiler/6603011/Test.java
changeset 2031 24e034f56dcb
child 5547 f4b087cbb361
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/compiler/6603011/Test.java	Fri Feb 13 09:09:35 2009 -0800
@@ -0,0 +1,220 @@
+/*
+ * Copyright 2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/**
+ * @test
+ * @bug 6603011
+ * @summary long/int division by constant
+ *
+ * @run main/othervm -Xcomp -Xbatch -XX:-Inline Test
+ */
+
+//
+// -XX:-Inline is essential to this test so that verification functions
+//   divi, modi, divl and modl generate "plain" divides.
+// -Xcomp -Xbatch are also useful to ensure the full range of
+//   dividend and divisor combinations are tested
+//
+
+import java.net.*;
+
+class s {
+  static int  divi(int  dividend, int  divisor) { return dividend / divisor; }
+  static int  modi(int  dividend, int  divisor) { return dividend % divisor; }
+  static long divl(long dividend, long divisor) { return dividend / divisor; }
+  static long modl(long dividend, long divisor) { return dividend % divisor; }
+}
+
+public class Test implements Runnable {
+  // Report verbose messages on failure; turn off to suppress
+  // too much output with gross numbers of failures.
+  static final boolean VERBOSE = true;
+
+  // Initailize DIVISOR so that it is final in this class.
+  static final int DIVISOR;
+  static {
+    int value = 0;
+    try {
+      value = Integer.decode(System.getProperty("divisor"));
+    } catch (Throwable e) {
+    }
+    DIVISOR = value;
+  }
+
+  // The methods of interest. We want the JIT to compile these
+  // and convert the divide into a multiply.
+  public int divbyI (int dividend)   { return dividend / DIVISOR; }
+  public int modbyI (int dividend)   { return dividend % DIVISOR; }
+  public long divbyL (long dividend) { return dividend / DIVISOR; }
+  public long modbyL (long dividend) { return dividend % DIVISOR; }
+
+  public int divisor() { return DIVISOR; }
+
+  public boolean checkI (int dividend) {
+    int quo = divbyI(dividend);
+    int rem = modbyI(dividend);
+    int quo0 = s.divi(dividend, divisor());
+    int rem0 = s.modi(dividend, divisor());
+
+    if (quo != quo0 || rem != rem0) {
+      if (VERBOSE) {
+        System.out.println("Computed: " + dividend + " / " + divisor() + " = " +
+                           quo  + ", " + dividend + " % " + divisor() + " = " + rem );
+        System.out.println("expected: " + dividend + " / " + divisor() + " = " +
+                           quo0 + ", " + dividend + " % " + divisor() + " = " + rem0);
+        // Report sign of rem failure
+        if (rem != 0 && (rem ^ dividend) < 0) {
+          System.out.println("  rem & dividend have different signs");
+        }
+        // Report range of rem failure
+        if (java.lang.Math.abs(rem) >= java.lang.Math.abs(divisor())) {
+          System.out.println("  remainder out of range");
+        }
+        // Report quo/rem identity relationship failure
+        if ((quo * divisor()) + rem != dividend) {
+          System.out.println("  quotien/remainder invariant broken");
+        }
+      }
+      return false;
+    }
+    return true;
+  }
+
+  public boolean checkL (long dividend) {
+    long quo = divbyL(dividend);
+    long rem = modbyL(dividend);
+    long quo0 = s.divl(dividend, divisor());
+    long rem0 = s.modl(dividend, divisor());
+
+    if (quo != quo0 || rem != rem0) {
+      if (VERBOSE) {
+        System.out.println("  " + dividend + " / " + divisor() + " = " +
+                           quo + ", " + dividend + " % " + divisor() + " = " + rem);
+        // Report sign of rem failure
+        if (rem != 0 && (rem ^ dividend) < 0) {
+          System.out.println("  rem & dividend have different signs");
+        }
+        // Report range of rem failure
+        if (java.lang.Math.abs(rem) >= java.lang.Math.abs(divisor())) {
+          System.out.println("  remainder out of range");
+        }
+        // Report quo/rem identity relationship failure
+        if ((quo * divisor()) + rem != dividend) {
+          System.out.println(" (" + quo + " * " + divisor() + ") + " + rem + " != "
+                             + dividend);
+        }
+      }
+      return false;
+    }
+    return true;
+  }
+
+  public void run() {
+    // Don't try to divide by zero
+    if (divisor() == 0) return;
+
+    // Range of dividends to check. Try dividends from start to end
+    // inclusive, as well as variations on those values as shifted
+    // left.
+    int start = -1024;
+    int end = 1024;
+
+    // Test int division using a variety of dividends.
+    int wrong = 0;
+    int total = 0;
+
+    outerloop:
+    for (int i = start; i <= end; i++) {
+      for (int s = 0; s < 32; s += 4) {
+        total++;
+        int dividend = i << s;
+        if (!checkI(dividend)) {
+          wrong++;
+          // Stop on the first failure
+          // break outerloop;
+        }
+      }
+    }
+    if (wrong > 0) {
+      System.out.println("divisor " + divisor() + ": " +
+                         wrong + "/" + total + " wrong int divisions");
+    }
+
+    // Test long division using a variety of dividends.
+    wrong = 0;
+    total = 0;
+
+    outerloop:
+    for (int i = start; i <= end; i++) {
+      for (int s = 0; s < 64; s += 4) {
+        total++;
+        long dividend = i << s;
+        if (!checkL(dividend)) {
+          wrong++;
+          // Stop on the first failure
+          // break outerloop;
+        }
+      }
+    }
+    if (wrong > 0) {
+      System.out.println("divisor " + divisor() + ": " +
+                         wrong + "/" + total + " wrong long divisions");
+    }
+
+  }
+
+  // Reload this class with the "divisor" property set to the input parameter.
+  // This allows the JIT to see q.DIVISOR as a final constant, and change
+  // any divisions or mod operations into multiplies.
+  public static void test_divisor(int divisor,
+                                  URLClassLoader apploader) throws Exception {
+    System.setProperty("divisor", "" + divisor);
+    ClassLoader loader = new URLClassLoader(apploader.getURLs(),
+                                            apploader.getParent());
+    Class c = loader.loadClass("Test");
+    Runnable r = (Runnable)c.newInstance();
+    r.run();
+  }
+
+  public static void main(String[] args) throws Exception {
+    Class cl = Class.forName("Test");
+    URLClassLoader apploader = (URLClassLoader)cl.getClassLoader();
+
+
+    // Test every divisor between -100 and 100.
+    for (int i = -100; i <= 100; i++) {
+      test_divisor(i, apploader);
+    }
+
+    // Try a few divisors outside the typical range.
+    // The values below have been observed in rt.jar.
+    test_divisor(101, apploader);
+    test_divisor(400, apploader);
+    test_divisor(1000, apploader);
+    test_divisor(3600, apploader);
+    test_divisor(9973, apploader);
+    test_divisor(86400, apploader);
+    test_divisor(1000000, apploader);
+  }
+
+}