kc3-lang/gnulib/tests/test-integer_length.c

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• Hash : 1602f0af
  Author :
  Date : 2012-01-01T10:04:58
  

  maint: update all copyright year number ranges
  
  Run "make update-copyright".
  

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• tests/test-integer_length.c

• /* Test of integer_length().
     Copyright (C) 2011-2012 Free Software Foundation, Inc.
  
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 3 of the License, or
     (at your option) any later version.
  
     This program 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 for more details.
  
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  
  #include <config.h>
  
  #include "integer_length.h"
  
  #include <limits.h>
  
  #include "macros.h"
  
  #define NBITS (sizeof (unsigned int) * CHAR_BIT)
  
  static int
  naive (unsigned int x)
  {
    int j;
    for (j = NBITS - 1; j >= 0; j--)
      if (x & (1U << j))
        return j + 1;
    return 0;
  }
  
  int
  main (int argc, char *argv[])
  {
    unsigned int x;
    int i;
  
    for (x = 0; x <= 256; x++)
      ASSERT (integer_length (x) == naive (x));
    for (i = 0; i < NBITS; i++)
      {
        ASSERT (integer_length (1U << i) == naive (1U << i));
        ASSERT (integer_length (1U << i) == i + 1);
        ASSERT (integer_length (-1U << i) == NBITS);
      }
    for (i = 0; i < NBITS - 1; i++)
      ASSERT (integer_length (3U << i) == i + 2);
    for (i = 0; i < NBITS - 2; i++)
      ASSERT (integer_length (-3U << i) == NBITS);
    for (i = 0; i < NBITS - 2; i++)
      {
        ASSERT (integer_length (5U << i) == i + 3);
        ASSERT (integer_length (7U << i) == i + 3);
      }
    for (i = 0; i < NBITS - 3; i++)
      {
        ASSERT (integer_length (-5U << i) == NBITS);
        ASSERT (integer_length (-7U << i) == NBITS);
      }
    return 0;
  }
  

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