libstdc++-v3/testsuite/23_containers/bitset_shift.cc

   1 // 2000-01-15  Anders Widell  <awl@hem.passagen.se>
   2
   3 // Copyright (C) 2000 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 // USA.
  20
  21 #include <string>
  22 #include <set>
  23 #include <bitset>
  24
  25 #include <testsuite_hooks.h>
  26
  27 static char original_bits[1024];
  28 static char left_shifted[1024];
  29 static char right_shifted[1024];
  30
  31 char
  32 random_bit() {
  33   static long x = 1;
  34   return ((x = (3432L*x + 6789L) % 9973L) & 1) + '0';
  35 }
  36
  37 void
  38 initialise(size_t size) {
  39   for (size_t i=0; i<size; i++)
  40     original_bits[i] = random_bit();
  41
  42   original_bits[size] = '\0';
  43   left_shifted[size] = '\0';
  44   right_shifted[size] = '\0';
  45 }
  46
  47 void
  48 shift_arrays(size_t shift_step, size_t size) {
  49   for (size_t i=shift_step; i<size; i++) {
  50     right_shifted[i] = original_bits[i-shift_step];
  51     left_shifted[size-i-1] = original_bits[size+shift_step-i-1];
  52   }
  53   for (size_t i=0; i<shift_step && i<size; i++) {
  54     right_shifted[i] = '0';
  55     left_shifted[size-i-1] = '0';
  56   }
  57 }
  58
  59 template <size_t size>
  60   bool
  61   do_test() {
  62     bool test = true;
  63
  64     std::bitset<size> shifted;
  65     std::bitset<size> correct;
  66
  67     initialise(size);
  68
  69     //std::bitset<size> original = std::string(original_bits);
  70     std::bitset<size> original = std::bitset<size> (std::string(original_bits));
  71
  72     for (size_t shift_step=0; shift_step==0 || shift_step<size; shift_step++) {
  73       shift_arrays(shift_step, size);
  74
  75       shifted = original;
  76       shifted <<= shift_step;
  77       //correct = std::string(left_shifted);
  78       correct = std::bitset<size> (std::string(left_shifted));
  79       VERIFY( shifted == correct );
  80
  81       shifted = original;
  82       shifted >>= shift_step;
  83       //correct = std::string(right_shifted);
  84       correct = std::bitset<size> (std::string(right_shifted));
  85       VERIFY( shifted == correct );
  86     }
  87
  88     return test;
  89   }
  90
  91 bool
  92 test01() {
  93   bool test = true;
  94
  95   VERIFY( do_test<32>() );
  96   VERIFY( do_test<48>() );
  97   VERIFY( do_test<64>() );
  98
  99   VERIFY( do_test<511>() );
 100   VERIFY( do_test<513>() );
 101   VERIFY( do_test<997>() );
 102
 103 #ifdef DEBUG_ASSERT
 104   assert(test);
 105 #endif
 106   return test;
 107 }
 108
 109 bool
 110 test02()
 111 {
 112   bool test = true;
 113
 114   std::bitset<66>  b;
 115   b <<= 400;
 116   VERIFY( b.count() == 0 );
 117
 118 #ifdef DEBUG_ASSERT
 119   assert(test);
 120 #endif
 121   return test;
 122 }
 123
 124 int
 125 main() {
 126   test01();
 127   test02();
 128
 129   return 0;
 130 }