1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 /*
  27  * @test
  28  * @bug 8054307
  29  * @summary Validates StringCoding.hasNegatives intrinsic with a small range of tests.
  30  * @library /compiler/patches
  31  * @build java.base/java.lang.Helper
  32  * @build compiler.intrinsics.string.TestHasNegatives
  33  * @run main compiler.intrinsics.string.TestHasNegatives
  34  */
  35 package compiler.intrinsics.string;
  36 
  37 import java.lang.Helper;
  38 
  39 /*
  40  * @summary Validates StringCoding.hasNegatives intrinsic with a small
  41  *          range of tests.
  42  */
  43 public class TestHasNegatives {
  44 
  45     private static byte[] tBa = new byte[4096 + 16];
  46 
  47     /**
  48      * Completely initialize the test array, preparing it for tests of the
  49      * StringCoding.hasNegatives method with a given array segment offset,
  50      * length, and number of negative bytes.
  51      */
  52     public static void initialize(int off, int len, int neg) {
  53         assert (len + off <= tBa.length);
  54         // insert "canary" (negative) values before offset
  55         for (int i = 0; i < off; ++i) {
  56             tBa[i] = (byte) (((i + 15) & 0x7F) | 0x80);
  57         }
  58         // fill the array segment
  59         for (int i = off; i < len + off; ++i) {
  60             tBa[i] = (byte) (((i - off + 15) & 0x7F));
  61         }
  62         if (neg != 0) {
  63             // modify a number (neg) disparate array bytes inside
  64             // segment to be negative.
  65             int div = (neg > 1) ? (len - 1) / (neg - 1) : 0;
  66             int idx;
  67             for (int i = 0; i < neg; ++i) {
  68                 idx = off + (len - 1) - div * i;
  69                 tBa[idx] = (byte) (0x80 | tBa[idx]);
  70             }
  71         }
  72         // insert "canary" negative values after array segment
  73         for (int i = len + off; i < tBa.length; ++i) {
  74             tBa[i] = (byte) (((i + 15) & 0x7F) | 0x80);
  75         }
  76     }
  77 
  78     /** Sizes of array segments to test. */
  79     private static int sizes[] = { 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 17, 19, 23, 37, 61, 131,
  80             4099 };
  81 
  82     /**
  83      * Test different array segment sizes, offsets, and number of negative
  84      * bytes.
  85      */
  86     public static void test_hasNegatives() throws Exception {
  87         int len, off;
  88         int ng;
  89         boolean r;
  90 
  91         for (ng = 0; ng < 57; ++ng) { // number of negatives in array segment
  92             for (off = 0; off < 8; ++off) { // starting offset of array segment
  93                 for (int i = 0; i < sizes.length; ++i) { // array segment size
  94                                                          // choice
  95                     len = sizes[i];
  96                     if (len + off > tBa.length)
  97                         continue;
  98                     initialize(off, len, ng);
  99                     r = Helper.StringCodingHasNegatives(tBa, off, len);
 100                     if (r ^ ((ng == 0) ? false : true)) {
 101                         throw new Exception("Failed test hasNegatives " + "offset: " + off + " "
 102                                 + "length: " + len + " " + "return: " + r + " " + "negatives: "
 103                                 + ng);
 104                     }
 105                 }
 106             }
 107         }
 108     }
 109 
 110     public void run() throws Exception {
 111         // iterate to eventually get intrinsic inlined
 112         for (int j = 0; j < 1000; ++j) {
 113             test_hasNegatives();
 114         }
 115     }
 116 
 117     public static void main(String[] args) throws Exception {
 118         (new TestHasNegatives()).run();
 119         System.out.println("hasNegatives validated");
 120     }
 121 }