builtin-bitops-1.c   [plain text]

#include <limits.h>
#include <assert.h>

#if __INT_MAX__ > 2147483647L
# if __INT_MAX__ >= 9223372036854775807L
#  define BITSIZEOF_INT 64
# else
#  define BITSIZEOF_INT 32
# endif
#else
# if __INT_MAX__ >= 2147483647L
#  define BITSIZEOF_INT 32
# else
#  define BITSIZEOF_INT 16
# endif
#endif

#if __LONG_MAX__ > 2147483647L
# if __LONG_MAX__ >= 9223372036854775807L
#  define BITSIZEOF_LONG 64
# else
#  define BITSIZEOF_LONG 32
# endif
#else
# define BITSIZEOF_LONG 32
#endif

#if __LONG_LONG_MAX__ > 2147483647L
# if __LONG_LONG_MAX__ >= 9223372036854775807L
#  define BITSIZEOF_LONG_LONG 64
# else
#  define BITSIZEOF_LONG_LONG 32
# endif
#else
# define BITSIZEOF_LONG_LONG 32
#endif

#define MAKE_FUNS(suffix, type)						\
int my_ffs##suffix(type x) {						\
    int i;								\
    if (x == 0)								\
	 return 0; 							\
    for (i = 0; i < CHAR_BIT * sizeof (type); i++)			\
	if (x & ((type) 1  << i))					\
	    break;							\
    return i + 1;							\
}									\
									\
int my_ctz##suffix(type x) {						\
    int i;								\
    for (i = 0; i < CHAR_BIT * sizeof (type); i++)			\
	if (x & ((type) 1  << i))					\
	    break;							\
    return i;								\
}									\
									\
int my_clz##suffix(type x) {						\
    int i;								\
    for (i = 0; i < CHAR_BIT * sizeof (type); i++)			\
	if (x & ((type) 1 << ((CHAR_BIT * sizeof (type)) - i - 1)))	\
	    break;							\
    return i;								\
}									\
									\
int my_popcount##suffix(type x) {					\
    int i;								\
    int count = 0;							\
    for (i = 0; i < CHAR_BIT * sizeof (type); i++)			\
	if (x & ((type) 1 << i))					\
	    count++;							\
    return count;							\
}									\
									\
int my_parity##suffix(type x) {						\
    int i;								\
    int count = 0;							\
    for (i = 0; i < CHAR_BIT * sizeof (type); i++)			\
	if (x & ((type) 1 << i))					\
	    count++;							\
    return count & 1;							\
}

MAKE_FUNS (, unsigned);
MAKE_FUNS (l, unsigned long);
MAKE_FUNS (ll, unsigned long long);

extern void abort (void);
extern void exit (int);

#define NUMS16					\
  {						\
    0x0000U,					\
    0x0001U,					\
    0x8000U,					\
    0x0002U,					\
    0x4000U,					\
    0x0100U,					\
    0x0080U,					\
    0xa5a5U,					\
    0x5a5aU,					\
    0xcafeU,					\
    0xffffU					\
  }

#define NUMS32					\
  {						\
    0x00000000UL,				\
    0x00000001UL,				\
    0x80000000UL,				\
    0x00000002UL,				\
    0x40000000UL,				\
    0x00010000UL,				\
    0x00008000UL,				\
    0xa5a5a5a5UL,				\
    0x5a5a5a5aUL,				\
    0xcafe0000UL,				\
    0x00cafe00UL,				\
    0x0000cafeUL,				\
    0xffffffffUL				\
  }

#define NUMS64					\
  {						\
    0x0000000000000000ULL,			\
    0x0000000000000001ULL,			\
    0x8000000000000000ULL,			\
    0x0000000000000002ULL,			\
    0x4000000000000000ULL,			\
    0x0000000100000000ULL,			\
    0x0000000080000000ULL,			\
    0xa5a5a5a5a5a5a5a5ULL,			\
    0x5a5a5a5a5a5a5a5aULL,			\
    0xcafecafe00000000ULL,			\
    0x0000cafecafe0000ULL,			\
    0x00000000cafecafeULL,			\
    0xffffffffffffffffULL			\
  }

unsigned int ints[] =
#if BITSIZEOF_INT == 64
NUMS64;
#elif BITSIZEOF_INT == 32
NUMS32;
#else
NUMS16;
#endif

unsigned long longs[] =
#if BITSIZEOF_LONG == 64
NUMS64;
#else
NUMS32;
#endif

unsigned long long longlongs[] =
#if BITSIZEOF_LONG_LONG == 64
NUMS64;
#else
NUMS32;
#endif

#define N(table) (sizeof (table) / sizeof (table[0]))

int
main (void)
{
  int i;

  for (i = 0; i < N(ints); i++)
    {
      if (__builtin_ffs (ints[i]) != my_ffs (ints[i]))
	abort ();
      if (ints[i] != 0
	  && __builtin_clz (ints[i]) != my_clz (ints[i]))
	abort ();
      if (ints[i] != 0
	  && __builtin_ctz (ints[i]) != my_ctz (ints[i]))
	abort ();
      if (__builtin_popcount (ints[i]) != my_popcount (ints[i]))
	abort ();
      if (__builtin_parity (ints[i]) != my_parity (ints[i]))
	abort ();
    }

  for (i = 0; i < N(longs); i++)
    {
      if (__builtin_ffsl (longs[i]) != my_ffsl (longs[i]))
	abort ();
      if (longs[i] != 0
	  && __builtin_clzl (longs[i]) != my_clzl (longs[i]))
	abort ();
      if (longs[i] != 0
	  && __builtin_ctzl (longs[i]) != my_ctzl (longs[i]))
	abort ();
      if (__builtin_popcountl (longs[i]) != my_popcountl (longs[i]))
	abort ();
      if (__builtin_parityl (longs[i]) != my_parityl (longs[i]))
	abort ();
    }

  for (i = 0; i < N(longlongs); i++)
    {
      if (__builtin_ffsll (longlongs[i]) != my_ffsll (longlongs[i]))
	abort ();
      if (longlongs[i] != 0
	  && __builtin_clzll (longlongs[i]) != my_clzll (longlongs[i]))
	abort ();
      if (longlongs[i] != 0
	  && __builtin_ctzll (longlongs[i]) != my_ctzll (longlongs[i]))
	abort ();
      if (__builtin_popcountll (longlongs[i]) != my_popcountll (longlongs[i]))
	abort ();
      if (__builtin_parityll (longlongs[i]) != my_parityll (longlongs[i]))
	abort ();
    }

  /* Test constant folding.  */

#define TEST(x, suffix)							\
  if (__builtin_ffs##suffix (x) != my_ffs##suffix (x))			\
    abort ();								\
  if (x != 0 && __builtin_clz##suffix (x) != my_clz##suffix (x))	\
    abort ();								\
  if (x != 0 && __builtin_ctz##suffix (x) != my_ctz##suffix (x))	\
    abort ();								\
  if (__builtin_popcount##suffix (x) != my_popcount##suffix (x))	\
    abort ();								\
  if (__builtin_parity##suffix (x) != my_parity##suffix (x))		\
    abort ();

#if BITSIZEOF_INT == 32
  TEST(0x00000000UL,);
  TEST(0x00000001UL,);
  TEST(0x80000000UL,);
  TEST(0x40000000UL,);
  TEST(0x00010000UL,);
  TEST(0x00008000UL,);
  TEST(0xa5a5a5a5UL,);
  TEST(0x5a5a5a5aUL,);
  TEST(0xcafe0000UL,);
  TEST(0x00cafe00UL,);
  TEST(0x0000cafeUL,);
  TEST(0xffffffffUL,);
#endif

#if BITSIZEOF_LONG_LONG == 64
  TEST(0x0000000000000000ULL, ll);
  TEST(0x0000000000000001ULL, ll);
  TEST(0x8000000000000000ULL, ll);
  TEST(0x0000000000000002ULL, ll);
  TEST(0x4000000000000000ULL, ll);
  TEST(0x0000000100000000ULL, ll);
  TEST(0x0000000080000000ULL, ll);
  TEST(0xa5a5a5a5a5a5a5a5ULL, ll);
  TEST(0x5a5a5a5a5a5a5a5aULL, ll);
  TEST(0xcafecafe00000000ULL, ll);
  TEST(0x0000cafecafe0000ULL, ll);
  TEST(0x00000000cafecafeULL, ll);
  TEST(0xffffffffffffffffULL, ll);
#endif

  exit (0);
}