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/* Test mpz_setbit, mpz_clrbit, mpz_tstbit.
Copyright 1997, 2000-2003, 2012, 2013 Free Software Foundation, Inc.
This file is part of the GNU MP Library test suite.
The GNU MP Library test suite 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.
The GNU MP Library test suite 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
the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */
#include <stdio.h>
#include <stdlib.h>
#include "gmp-impl.h"
#include "tests.h"
#ifndef SIZE
#define SIZE 4
#endif
void
debug_mp (mpz_srcptr x, int base)
{
mpz_out_str (stdout, base, x); fputc ('\n', stdout);
}
/* exercise the case where mpz_clrbit or mpz_combit ends up extending a
value like -2^(k*GMP_NUMB_BITS-1) when clearing bit k*GMP_NUMB_BITS-1. */
/* And vice-versa. */
void
check_clr_extend (void)
{
mpz_t got, want;
unsigned long i;
int f;
mpz_init (got);
mpz_init (want);
for (i = 1; i < 5; i++)
{
for (f = 0; f <= 1; f++)
{
/* lots of 1 bits in _mp_d */
mpz_set_si (got, 1L);
mpz_mul_2exp (got, got, 10*GMP_NUMB_BITS);
mpz_sub_ui (got, got, 1L);
/* value -2^(n-1) representing ..11100..00 */
mpz_set_si (got, -1L);
mpz_mul_2exp (got, got, i*GMP_NUMB_BITS-1);
/* complement bit n, giving ..11000..00 which is -2^n */
if (f == 0)
mpz_clrbit (got, i*GMP_NUMB_BITS-1);
else
mpz_combit (got, i*GMP_NUMB_BITS-1);
MPZ_CHECK_FORMAT (got);
mpz_set_si (want, -1L);
mpz_mul_2exp (want, want, i*GMP_NUMB_BITS);
if (mpz_cmp (got, want) != 0)
{
if (f == 0)
printf ("mpz_clrbit: ");
else
printf ("mpz_combit: ");
printf ("wrong after extension\n");
mpz_trace ("got ", got);
mpz_trace ("want", want);
abort ();
}
/* complement bit n, going back to ..11100..00 which is -2^(n-1) */
if (f == 0)
mpz_setbit (got, i*GMP_NUMB_BITS-1);
else
mpz_combit (got, i*GMP_NUMB_BITS-1);
MPZ_CHECK_FORMAT (got);
mpz_set_si (want, -1L);
mpz_mul_2exp (want, want, i*GMP_NUMB_BITS - 1);
if (mpz_cmp (got, want) != 0)
{
if (f == 0)
printf ("mpz_setbit: ");
else
printf ("mpz_combit: ");
printf ("wrong after shrinking\n");
mpz_trace ("got ", got);
mpz_trace ("want", want);
abort ();
}
}
}
mpz_clear (got);
mpz_clear (want);
}
void
check_com_negs (void)
{
static const struct {
unsigned long bit;
mp_size_t inp_size;
mp_limb_t inp_n[5];
mp_size_t want_size;
mp_limb_t want_n[5];
} data[] = {
{ GMP_NUMB_BITS, 2, { 1, 1 }, 1, { 1 } },
{ GMP_NUMB_BITS+1, 2, { 1, 1 }, 2, { 1, 3 } },
{ GMP_NUMB_BITS, 2, { 0, 1 }, 2, { 0, 2 } },
{ GMP_NUMB_BITS+1, 2, { 0, 1 }, 2, { 0, 3 } },
};
mpz_t inp, got, want;
int i;
mpz_init (got);
mpz_init (want);
mpz_init (inp);
for (i = 0; i < numberof (data); i++)
{
mpz_set_n (inp, data[i].inp_n, data[i].inp_size);
mpz_neg (inp, inp);
mpz_set_n (want, data[i].want_n, data[i].want_size);
mpz_neg (want, want);
mpz_set (got, inp);
mpz_combit (got, data[i].bit);
if (mpz_cmp (got, want) != 0)
{
printf ("mpz_combit: wrong on neg data[%d]\n", i);
mpz_trace ("inp ", inp);
printf ("bit %lu\n", data[i].bit);
mpz_trace ("got ", got);
mpz_trace ("want", want);
abort ();
}
}
mpz_clear (inp);
mpz_clear (got);
mpz_clear (want);
}
/* See that mpz_tstbit matches a twos complement calculated explicitly, for
various low zeros. */
void
check_tstbit (void)
{
#define MAX_ZEROS 3
#define NUM_LIMBS 3
mp_limb_t pos[1+NUM_LIMBS+MAX_ZEROS];
mp_limb_t neg[1+NUM_LIMBS+MAX_ZEROS];
mpz_t z;
unsigned long i;
int zeros, low1;
int got, want;
mpz_init (z);
for (zeros = 0; zeros <= MAX_ZEROS; zeros++)
{
MPN_ZERO (pos, numberof(pos));
mpn_random2 (pos+zeros, (mp_size_t) NUM_LIMBS);
for (low1 = 0; low1 <= 1; low1++)
{
if (low1)
pos[0] |= 1;
refmpn_neg (neg, pos, (mp_size_t) numberof(neg));
mpz_set_n (z, neg, (mp_size_t) numberof(neg));
mpz_neg (z, z);
for (i = 0; i < numberof(pos)*GMP_NUMB_BITS; i++)
{
got = mpz_tstbit (z, i);
want = refmpn_tstbit (pos, i);
if (got != want)
{
printf ("wrong at bit %lu, with %d zeros\n", i, zeros);
printf ("z neg "); debug_mp (z, -16);
mpz_set_n (z, pos, (mp_size_t) numberof(pos));
printf ("pos "); debug_mp (z, -16);
mpz_set_n (z, neg, (mp_size_t) numberof(neg));
printf ("neg "); debug_mp (z, -16);
exit (1);
}
}
}
}
mpz_clear (z);
}
void
check_single (void)
{
mpz_t x;
int limb, offset, initial;
unsigned long bit;
mpz_init (x);
for (limb = 0; limb < 4; limb++)
{
for (offset = (limb==0 ? 0 : -2); offset <= 2; offset++)
{
for (initial = 1; initial >= -1; initial--)
{
mpz_set_si (x, (long) initial);
bit = (unsigned long) limb*GMP_LIMB_BITS + offset;
mpz_clrbit (x, bit);
MPZ_CHECK_FORMAT (x);
if (mpz_tstbit (x, bit) != 0)
{
printf ("check_single(): expected 0\n");
abort ();
}
mpz_setbit (x, bit);
MPZ_CHECK_FORMAT (x);
if (mpz_tstbit (x, bit) != 1)
{
printf ("check_single(): expected 1\n");
abort ();
}
mpz_clrbit (x, bit);
MPZ_CHECK_FORMAT (x);
if (mpz_tstbit (x, bit) != 0)
{
printf ("check_single(): expected 0\n");
abort ();
}
mpz_combit (x, bit);
MPZ_CHECK_FORMAT (x);
if (mpz_tstbit (x, bit) != 1)
{
printf ("check_single(): expected 1\n");
abort ();
}
mpz_combit (x, bit);
MPZ_CHECK_FORMAT (x);
if (mpz_tstbit (x, bit) != 0)
{
printf ("check_single(): expected 0\n");
abort ();
}
}
}
}
mpz_clear (x);
}
void
check_random (int argc, char *argv[])
{
mpz_t x, s0, s1, s2, s3, m;
mp_size_t xsize;
int i;
int reps = 100000;
int bit0, bit1, bit2, bit3;
unsigned long int bitindex;
const char *s = "";
if (argc == 2)
reps = atoi (argv[1]);
mpz_init (x);
mpz_init (s0);
mpz_init (s1);
mpz_init (s2);
mpz_init (s3);
mpz_init (m);
for (i = 0; i < reps; i++)
{
xsize = urandom () % (2 * SIZE) - SIZE;
mpz_random2 (x, xsize);
bitindex = urandom () % SIZE;
mpz_set (s0, x);
bit0 = mpz_tstbit (x, bitindex);
mpz_setbit (x, bitindex);
MPZ_CHECK_FORMAT (x);
mpz_set (s1, x);
bit1 = mpz_tstbit (x, bitindex);
mpz_clrbit (x, bitindex);
MPZ_CHECK_FORMAT (x);
mpz_set (s2, x);
bit2 = mpz_tstbit (x, bitindex);
mpz_combit (x, bitindex);
MPZ_CHECK_FORMAT (x);
mpz_set (s3, x);
bit3 = mpz_tstbit (x, bitindex);
#define FAIL(str) do { s = str; goto fail; } while (0)
if (bit1 != 1) FAIL ("bit1 != 1");
if (bit2 != 0) FAIL ("bit2 != 0");
if (bit3 != 1) FAIL ("bit3 != 1");
if (bit0 == 0)
{
if (mpz_cmp (s0, s1) == 0 || mpz_cmp (s0, s2) != 0 || mpz_cmp (s0, s3) == 0)
abort ();
}
else
{
if (mpz_cmp (s0, s1) != 0 || mpz_cmp (s0, s2) == 0 || mpz_cmp (s0, s3) != 0)
abort ();
}
if (mpz_cmp (s1, s2) == 0 || mpz_cmp (s1, s3) != 0)
abort ();
if (mpz_cmp (s2, s3) == 0)
abort ();
mpz_combit (x, bitindex);
MPZ_CHECK_FORMAT (x);
if (mpz_cmp (s2, x) != 0)
abort ();
mpz_clrbit (x, bitindex);
MPZ_CHECK_FORMAT (x);
if (mpz_cmp (s2, x) != 0)
abort ();
mpz_ui_pow_ui (m, 2L, bitindex);
MPZ_CHECK_FORMAT (m);
mpz_ior (x, s0, m);
MPZ_CHECK_FORMAT (x);
if (mpz_cmp (x, s3) != 0)
abort ();
mpz_com (m, m);
MPZ_CHECK_FORMAT (m);
mpz_and (x, s0, m);
MPZ_CHECK_FORMAT (x);
if (mpz_cmp (x, s2) != 0)
abort ();
}
mpz_clear (x);
mpz_clear (s0);
mpz_clear (s1);
mpz_clear (s2);
mpz_clear (s3);
mpz_clear (m);
return;
fail:
printf ("%s\n", s);
printf ("bitindex = %lu\n", bitindex);
printf ("x = "); mpz_out_str (stdout, -16, x); printf (" hex\n");
exit (1);
}
int
main (int argc, char *argv[])
{
tests_start ();
mp_trace_base = -16;
check_clr_extend ();
check_com_negs ();
check_tstbit ();
check_random (argc, argv);
check_single ();
tests_end ();
exit (0);
}
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