modernc.org/cc@v1.0.1/testdata/gcc-6.3.0/gcc/testsuite/gcc.c-torture/execute/ieee/copysign2.c (about)

     1  #include <string.h>
     2  #include <stdlib.h>
     3  #include <float.h>
     4  
     5  #define fpsizeoff	sizeof(float)
     6  #define fpsizeof	sizeof(double)
     7  #define fpsizeofl	sizeof(long double)
     8  
     9  /* Work around the fact that with the Intel double-extended precision,
    10     we've got a 10 byte type stuffed into some amount of padding.  And
    11     the fact that -ffloat-store is going to stuff this value temporarily
    12     into some bit of stack frame that we've no control over and can't zero.  */
    13  #if LDBL_MANT_DIG == 64
    14  # if defined(__i386__) || defined(__x86_64__) || defined (__ia64__)
    15  #  undef fpsizeofl
    16  #  define fpsizeofl	10
    17  # endif
    18  #endif
    19  
    20  /* Work around the fact that the sign of the second double in the IBM
    21     double-double format is not strictly specified when it contains a zero.
    22     For instance, -0.0L can be represented with either (-0.0, +0.0) or
    23     (-0.0, -0.0).  The former is what we'll get from the compiler when it
    24     builds constants; the later is what we'll get from the negation operator
    25     at runtime.  */
    26  /* ??? This hack only works for big-endian, which is fortunately true for
    27     AIX and Darwin.  */
    28  #if LDBL_MANT_DIG == 106
    29  # undef fpsizeofl
    30  # define fpsizeofl	sizeof(double)
    31  #endif
    32  
    33  
    34  #define TEST(TYPE, EXT)						\
    35  static TYPE Y##EXT[] = {					\
    36    2.0, -2.0, -2.0, -2.0, -2.0, 2.0, -0.0, __builtin_inf##EXT ()	\
    37  };								\
    38  static const TYPE Z##EXT[] = {					\
    39    1.0, -1.0, -1.0, -0.0, -0.0, 0.0, -__builtin_inf##EXT (),	\
    40    __builtin_nan##EXT ("")					\
    41  };								\
    42  								\
    43  void test##EXT (void)						\
    44  {								\
    45    TYPE r[8];							\
    46    int i;							\
    47    r[0] = __builtin_copysign##EXT (1.0, Y##EXT[0]);		\
    48    r[1] = __builtin_copysign##EXT (1.0, Y##EXT[1]);		\
    49    r[2] = __builtin_copysign##EXT (-1.0, Y##EXT[2]);		\
    50    r[3] = __builtin_copysign##EXT (0.0, Y##EXT[3]);		\
    51    r[4] = __builtin_copysign##EXT (-0.0, Y##EXT[4]);		\
    52    r[5] = __builtin_copysign##EXT (-0.0, Y##EXT[5]);		\
    53    r[6] = __builtin_copysign##EXT (__builtin_inf##EXT (), Y##EXT[6]); \
    54    r[7] = __builtin_copysign##EXT (-__builtin_nan##EXT (""), Y##EXT[7]); \
    55    for (i = 0; i < 8; ++i)					\
    56      if (memcmp (r+i, Z##EXT+i, fpsizeof##EXT) != 0)		\
    57        abort ();							\
    58  }
    59  
    60  TEST(float, f)
    61  TEST(double, )
    62  TEST(long double, l)
    63  
    64  int main()
    65  {
    66    testf();
    67    test();
    68    testl();
    69    return 0;
    70  }