vm/oops/dByteArrayOop.cpp

   1 /* Copyright 1994, 1995 LongView Technologies L.L.C. $Revision: 1.19 $ */
   2 /* Copyright (c) 2006, Sun Microsystems, Inc.
   3 All rights reserved.
   4
   5 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
   6 following conditions are met:
   7
   8     * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
   9     * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
  10           disclaimer in the documentation and/or other materials provided with the distribution.
  11     * Neither the name of Sun Microsystems nor the names of its contributors may be used to endorse or promote products derived
  12           from this software without specific prior written permission.
  13
  14 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
  15 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  16 THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  17 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  18 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
  19 OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
  20
  21
  22 */
  23
  24 # include "incls/_precompiled.incl"
  25 # include "incls/_dByteArrayOop.cpp.incl"
  26
  27 bool doubleByteArrayOopDesc::verify() {
  28   bool flag = memOopDesc::verify();
  29   if (flag) {
  30     int l = length();
  31     if (l < 0) {
  32       error("doubleByteArrayOop %#lx has negative length", this);
  33       flag = false;
  34     }
  35   }
  36   return flag;
  37 }
  38
  39 void doubleByteArrayOopDesc::bootstrap_object(bootstrap* st) {
  40   memOopDesc::bootstrap_object(st);
  41   st->read_oop(length_addr());
  42   for (int index = 1; index <= length(); index++)
  43     doubleByte_at_put(index, st->read_doubleByte());
  44 }
  45
  46 inline int sub_sign(int a, int b) {
  47   if (a < b) return -1;
  48   if (a > b) return  1;
  49   return 0;
  50 }
  51
  52 inline int compare_as_doubleBytes(const doubleByte* a, const doubleByte* b) {
  53   // machine dependent code; little endian code
  54   if (a[0] - b[0]) return sub_sign(a[0], b[0]);
  55   return sub_sign(a[1], b[1]);
  56 }
  57
  58 int doubleByteArrayOopDesc::compare(doubleByteArrayOop arg) {
  59   // Get the addresses of the length fields
  60   const unsigned int* a = (const unsigned int*) length_addr();
  61   const unsigned int* b = (const unsigned int*) arg->length_addr();
  62
  63   // Get the word sizes of the arays
  64   int a_size = roundTo(smiOop(*a++)->value() * sizeof(doubleByte), sizeof(int)) / sizeof(int);
  65   int b_size = roundTo(smiOop(*b++)->value() * sizeof(doubleByte), sizeof(int)) / sizeof(int);
  66
  67   const unsigned int* a_end = a + min(a_size, b_size);
  68   while(a < a_end) {
  69     if (*b++ != *a++)
  70       return compare_as_doubleBytes((const doubleByte*) (a-1), (const doubleByte*) (b-1));
  71   }
  72   return sub_sign(a_size, b_size);
  73 }
  74
  75 /*
  76 int doubleByteArrayOopDesc::compare(doubleByteArrayOop arg) {
  77   // Get the addresses of the length fields
  78   int         len_a = length();
  79   doubleByte* a     = doubleBytes();
  80
  81   int         len_b = arg->length();
  82   doubleByte* b     = arg->doubleBytes();
  83
  84   doubleByte* end = len_a <= len_b ? a + len_a : b + len_b;
  85
  86   while(a < end) {
  87     int result = *a++ - *b++;
  88     if (result != 0) {
  89       if (result < 0) return -1;
  90       if (result > 0) return  1;
  91     }
  92   }
  93   return sub_sign(len_a, len_b);
  94 }
  95 */
  96
  97 int doubleByteArrayOopDesc::hash_value() {
  98   int len = length();
  99   int result;
 100
 101   if (len == 0) {
 102     result = 1;
 103   } else if (len == 1) {
 104     result = doubleByte_at(1);
 105   } else {
 106     unsigned int val;
 107     val = doubleByte_at(1);
 108     val = (val << 3) ^ (doubleByte_at(2)         ^ val);
 109     val = (val << 3) ^ (doubleByte_at(len)       ^ val);
 110     val = (val << 3) ^ (doubleByte_at(len-1)     ^ val);
 111     val = (val << 3) ^ (doubleByte_at(len/2 + 1) ^ val);
 112     val = (val << 3) ^ (len                      ^ val);
 113     result = markOopDesc::masked_hash(val);
 114   }
 115   return result == 0 ? 1 : result;
 116 }
 117
 118
 119 bool doubleByteArrayOopDesc::copy_null_terminated(char* buffer, int max_length) {
 120   int len = length();
 121   bool is_truncated = false;
 122   if (len >= max_length) {
 123     len = max_length - 1;
 124     is_truncated = true;
 125   }
 126   for (int index = 0; index < len; index++)
 127     buffer[index] = (char) doubleByte_at(index+1);
 128   buffer[len]= '\0';
 129   return is_truncated;
 130 }
 131
 132 char* doubleByteArrayOopDesc::as_string() {
 133   int len = length();
 134   char* str = NEW_RESOURCE_ARRAY(char, len+1);
 135   for (int index = 0; index <len; index++) {
 136     str[index] = (char) doubleByte_at(index+1);
 137   }
 138   str[index] = '\0';
 139   return str;
 140 }
 141