jdk8-mips64-public/hotspot: test/compiler/intrinsics/montgomerymultiply/MontgomeryMultiplyTest.java@5601e440e5e7

8130150: Implement BigInteger.montgomeryMultiply intrinsic
Reviewed-by: kvn, mdoerr

     1 //

     2 // Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.

     3 // Copyright (c) 2015, Red Hat Inc. All rights reserved.

     4 // DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     5 //

     6 // This code is free software; you can redistribute it and/or modify it

     7 // under the terms of the GNU General Public License version 2 only, as

     8 // published by the Free Software Foundation.

     9 //

    10 // This code is distributed in the hope that it will be useful, but WITHOUT

    11 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    12 // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    13 // version 2 for more details (a copy is included in the LICENSE file that

    14 // accompanied this code).

    15 //

    16 // You should have received a copy of the GNU General Public License version

    17 // 2 along with this work; if not, write to the Free Software Foundation,

    18 // Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    19 //

    20 // Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21 // or visit www.oracle.com if you need additional information or have any

    22 // questions.

    23 //

    24 //

    26 import java.lang.invoke.MethodHandle;

    27 import java.lang.invoke.MethodHandles;

    28 import java.lang.invoke.MethodType;

    29 import java.lang.reflect.Constructor;

    30 import java.lang.reflect.Field;

    31 import java.lang.reflect.Method;

    32 import java.math.BigInteger;

    33 import java.util.Arrays;

    34 import java.util.Random;

    36 /**

    37  * @test

    38  * @bug 8130150

    39  * @library /testlibrary

    40  * @requires (os.simpleArch == "x64") & (os.family != "windows")

    41  * @summary Verify that the Montgomery multiply intrinsic works and correctly checks its arguments.

    42  */

    44 public class MontgomeryMultiplyTest {

    46     static final MethodHandles.Lookup lookup = MethodHandles.lookup();

    48     static final MethodHandle montgomeryMultiplyHandle, montgomerySquareHandle;

    49     static final MethodHandle bigIntegerConstructorHandle;

    50     static final Field bigIntegerMagField;

    52     static {

    53        // Use reflection to gain access to the methods we want to test.

    54         try {

    55             Method m = BigInteger.class.getDeclaredMethod("montgomeryMultiply",

    56                 /*a*/int[].class, /*b*/int[].class, /*n*/int[].class, /*len*/int.class,

    57                 /*inv*/long.class, /*product*/int[].class);

    58             m.setAccessible(true);

    59             montgomeryMultiplyHandle = lookup.unreflect(m);

    61             m = BigInteger.class.getDeclaredMethod("montgomerySquare",

    62                 /*a*/int[].class, /*n*/int[].class, /*len*/int.class,

    63                 /*inv*/long.class, /*product*/int[].class);

    64             m.setAccessible(true);

    65             montgomerySquareHandle = lookup.unreflect(m);

    67             Constructor c

    68                 = BigInteger.class.getDeclaredConstructor(int.class, int[].class);

    69             c.setAccessible(true);

    70             bigIntegerConstructorHandle = lookup.unreflectConstructor(c);

    72             bigIntegerMagField = BigInteger.class.getDeclaredField("mag");

    73             bigIntegerMagField.setAccessible(true);

    75         } catch (Throwable ex) {

    76             throw new RuntimeException(ex);

    77         }

    78     }

    80     // Invoke either BigInteger.montgomeryMultiply or BigInteger.montgomerySquare.

    81     int[] montgomeryMultiply(int[] a, int[] b, int[] n, int len, long inv,

    82                              int[] product) throws Throwable {

    83         int[] result =

    84             (a == b) ? (int[]) montgomerySquareHandle.invokeExact(a, n, len, inv, product)

    85                      : (int[]) montgomeryMultiplyHandle.invokeExact(a, b, n, len, inv, product);

    86         return Arrays.copyOf(result, len);

    87     }

    89     // Invoke the private constructor BigInteger(int[]).

    90     BigInteger newBigInteger(int[] val) throws Throwable {

    91         return (BigInteger) bigIntegerConstructorHandle.invokeExact(1, val);

    92     }

    94     // Get the private field BigInteger.mag

    95     int[] mag(BigInteger n) {

    96         try {

    97             return (int[]) bigIntegerMagField.get(n);

    98         } catch (Exception ex) {

    99             throw new RuntimeException(ex);

   100         }

   101     }

   103     // Montgomery multiplication

   104     // Calculate a * b * r^-1 mod n)

   105     //

   106     // R is a power of the word size

   107     // N' = R^-1 mod N

   108     //

   109     // T := ab

   110     // m := (T mod R)N' mod R [so 0 <= m < R]

   111     // t := (T + mN)/R

   112     // if t >= N then return t - N else return t

   113     //

   114     BigInteger montgomeryMultiply(BigInteger a, BigInteger b, BigInteger N,

   115             int len, BigInteger n_prime)

   116             throws Throwable {

   117         BigInteger T = a.multiply(b);

   118         BigInteger R = BigInteger.ONE.shiftLeft(len*32);

   119         BigInteger mask = R.subtract(BigInteger.ONE);

   120         BigInteger m = (T.and(mask)).multiply(n_prime);

   121         m = m.and(mask); // i.e. m.mod(R)

   122         T = T.add(m.multiply(N));

   123         T = T.shiftRight(len*32); // i.e. T.divide(R)

   124         if (T.compareTo(N) > 0) {

   125             T = T.subtract(N);

   126         }

   127         return T;

   128     }

   130     // Call the Montgomery multiply intrinsic.

   131     BigInteger montgomeryMultiply(int[] a_words, int[] b_words, int[] n_words,

   132             int len, BigInteger inv)

   133             throws Throwable {

   134         BigInteger t = montgomeryMultiply(

   135                 newBigInteger(a_words),

   136                 newBigInteger(b_words),

   137                 newBigInteger(n_words),

   138                 len, inv);

   139         return t;

   140     }

   142     // Check that the Montgomery multiply intrinsic returns the same

   143     // result as the longhand calculation.

   144     void check(int[] a_words, int[] b_words, int[] n_words, int len, BigInteger inv)

   145             throws Throwable {

   146         BigInteger n = newBigInteger(n_words);

   147         BigInteger slow = montgomeryMultiply(a_words, b_words, n_words, len, inv);

   148         BigInteger fast

   149             = newBigInteger(montgomeryMultiply

   150                             (a_words, b_words, n_words, len, inv.longValue(), null));

   151         // The intrinsic may not return the same value as the longhand

   152         // calculation but they must have the same residue mod N.

   153         if (!slow.mod(n).equals(fast.mod(n))) {

   154             throw new RuntimeException();

   155         }

   156     }

   158     Random rnd = new Random(0);

   160     // Return a random value of length <= bits in an array of even length

   161     int[] random_val(int bits) {

   162         int len = (bits+63)/64;  // i.e. length in longs

   163         int[] val = new int[len*2];

   164         for (int i = 0; i < val.length; i++)

   165             val[i] = rnd.nextInt();

   166         int leadingZeros = 64 - (bits & 64);

   167         if (leadingZeros >= 32) {

   168             val[0] = 0;

   169             val[1] &= ~(-1l << (leadingZeros & 31));

   170         } else {

   171             val[0] &= ~(-1l << leadingZeros);

   172         }

   173         return val;

   174     }

   176     void testOneLength(int lenInBits, int lenInInts) throws Throwable {

   177         BigInteger mod = new BigInteger(lenInBits, 2, rnd);

   178         BigInteger r = BigInteger.ONE.shiftLeft(lenInInts * 32);

   179         BigInteger n_prime = mod.modInverse(r).negate();

   181         // Make n.length even, padding with a zero if necessary

   182         int[] n = mag(mod);

   183         if (n.length < lenInInts) {

   184             int[] x = new int[lenInInts];

   185             System.arraycopy(n, 0, x, lenInInts-n.length, n.length);

   186             n = x;

   187         }

   189         for (int i = 0; i < 10000; i++) {

   190             // multiply

   191             check(random_val(lenInBits), random_val(lenInBits), n, lenInInts, n_prime);

   192             // square

   193             int[] tmp = random_val(lenInBits);

   194             check(tmp, tmp, n, lenInInts, n_prime);

   195         }

   196     }

   198     // Test the Montgomery multiply intrinsic with a bunch of random

   199     // values of varying lengths.  Do this for long enough that the

   200     // caller of the intrinsic is C2-compiled.

   201     void testResultValues() throws Throwable {

   202         // Test a couple of interesting edge cases.

   203         testOneLength(1024, 32);

   204         testOneLength(1025, 34);

   205         for (int j = 10; j > 0; j--) {

   206             // Construct a random prime whose length in words is even

   207             int lenInBits = rnd.nextInt(2048) + 64;

   208             int lenInInts = (lenInBits + 63)/64*2;

   209             testOneLength(lenInBits, lenInInts);

   210         }

   211     }

   213     // Range checks

   214     void testOneMontgomeryMultiplyCheck(int[] a, int[] b, int[] n, int len, long inv,

   215                                         int[] product, Class klass) {

   216         try {

   217             montgomeryMultiply(a, b, n, len, inv, product);

   218         } catch (Throwable ex) {

   219             if (klass.isAssignableFrom(ex.getClass()))

   220                 return;

   221             throw new RuntimeException(klass + " expected, " + ex + " was thrown");

   222         }

   223         throw new RuntimeException(klass + " expected, was not thrown");

   224     }

   226     void testOneMontgomeryMultiplyCheck(int[] a, int[] b, BigInteger n, int len, BigInteger inv,

   227             Class klass) {

   228         testOneMontgomeryMultiplyCheck(a, b, mag(n), len, inv.longValue(), null, klass);

   229     }

   231     void testOneMontgomeryMultiplyCheck(int[] a, int[] b, BigInteger n, int len, BigInteger inv,

   232             int[] product, Class klass) {

   233         testOneMontgomeryMultiplyCheck(a, b, mag(n), len, inv.longValue(), product, klass);

   234     }

   236     void testMontgomeryMultiplyChecks() {

   237         int[] blah = random_val(40);

   238         int[] small = random_val(39);

   239         BigInteger mod = new BigInteger(40*32 , 2, rnd);

   240         BigInteger r = BigInteger.ONE.shiftLeft(40*32);

   241         BigInteger n_prime = mod.modInverse(r).negate();

   243         // Length out of range: square

   244         testOneMontgomeryMultiplyCheck(blah, blah, mod, 41, n_prime, IllegalArgumentException.class);

   245         testOneMontgomeryMultiplyCheck(blah, blah, mod, 0, n_prime, IllegalArgumentException.class);

   246         testOneMontgomeryMultiplyCheck(blah, blah, mod, -1, n_prime, IllegalArgumentException.class);

   247         // As above, but for multiply

   248         testOneMontgomeryMultiplyCheck(blah, blah.clone(), mod, 41, n_prime, IllegalArgumentException.class);

   249         testOneMontgomeryMultiplyCheck(blah, blah.clone(), mod, 0, n_prime, IllegalArgumentException.class);

   250         testOneMontgomeryMultiplyCheck(blah, blah.clone(), mod, 0, n_prime, IllegalArgumentException.class);

   252         // Length odd

   253         testOneMontgomeryMultiplyCheck(small, small, mod, 39, n_prime, IllegalArgumentException.class);

   254         testOneMontgomeryMultiplyCheck(small, small, mod, 0, n_prime, IllegalArgumentException.class);

   255         testOneMontgomeryMultiplyCheck(small, small, mod, -1, n_prime, IllegalArgumentException.class);

   256         // As above, but for multiply

   257         testOneMontgomeryMultiplyCheck(small, small.clone(), mod, 39, n_prime, IllegalArgumentException.class);

   258         testOneMontgomeryMultiplyCheck(small, small.clone(), mod, 0, n_prime, IllegalArgumentException.class);

   259         testOneMontgomeryMultiplyCheck(small, small.clone(), mod, -1, n_prime, IllegalArgumentException.class);

   261         // array too small

   262         testOneMontgomeryMultiplyCheck(blah, blah, mod, 40, n_prime, small, IllegalArgumentException.class);

   263         testOneMontgomeryMultiplyCheck(blah, blah.clone(), mod, 40, n_prime, small, IllegalArgumentException.class);

   264         testOneMontgomeryMultiplyCheck(small, blah, mod, 40, n_prime, blah, IllegalArgumentException.class);

   265         testOneMontgomeryMultiplyCheck(blah, small, mod, 40, n_prime, blah, IllegalArgumentException.class);

   266         testOneMontgomeryMultiplyCheck(blah, blah, mod, 40, n_prime, small, IllegalArgumentException.class);

   267         testOneMontgomeryMultiplyCheck(small, small, mod, 40, n_prime, blah, IllegalArgumentException.class);

   268     }

   270     public static void main(String args[]) {

   271         try {

   272             new MontgomeryMultiplyTest().testMontgomeryMultiplyChecks();

   273             new MontgomeryMultiplyTest().testResultValues();

   274         } catch (Throwable ex) {

   275             throw new RuntimeException(ex);

   276         }

   277      }

   278 }

Mercurial > jdk8-mips64-public > hotspot / file revision

test/compiler/intrinsics/montgomerymultiply/MontgomeryMultiplyTest.java@5601e440e5e7

test/compiler/intrinsics/montgomerymultiply/MontgomeryMultiplyTest.java