opemu_math.h

/* Needed unions */
typedef union
{
    float value;
    uint32_t word;
} ieee_float_shape_type;

typedef union
{
    double value;
    struct
    {
        uint32_t lsw;
        uint32_t msw;
    } parts;
} ieee_double_shape_type;

typedef union
{
    long double value;
    struct
    {
        uint64_t lsw;
        uint64_t msw;
    } parts;
} ieee_long_double_shape_type;

/* 32-bit (float) */
#define GET_FLOAT_WORD(i,d) \
  do { \
    ieee_float_shape_type gf_u; \
    gf_u.value = (d); \
    (i) = gf_u.word; \
  } while (0)

#define SET_FLOAT_WORD(d,i) \
  do { \
    ieee_float_shape_type sf_u; \
    sf_u.word = (i); \
    (d) = sf_u.value; \
  } while (0)

/* 64-bit (double) */
#define EXTRACT_WORDS(ix0,ix1,d) \
  do { \
    ieee_double_shape_type ew_u; \
    ew_u.value = (d); \
    (ix0) = ew_u.parts.msw; \
    (ix1) = ew_u.parts.lsw; \
  } while (0)

#define INSERT_WORDS(d,ix0,ix1) \
  do { \
    ieee_double_shape_type iw_u; \
    iw_u.parts.msw = (ix0); \
    iw_u.parts.lsw = (ix1); \
    (d) = iw_u.value; \
  } while (0)

/* 128-bit (long double) */
#define GET_LDOUBLE_WORDS(ix0,ix1,d) \
  do { \
    ieee_long_double_shape_type qw_u; \
    qw_u.value = (d); \
    (ix0) = qw_u.parts.msw; \
    (ix1) = qw_u.parts.lsw; \
  } while (0)

#define SET_LDOUBLE_WORDS(d,ix0,ix1) \
  do { \
    ieee_long_double_shape_type qw_u; \
    qw_u.parts.msw = (ix0); \
    qw_u.parts.lsw = (ix1); \
    (d) = qw_u.value; \
  } while (0)

float opemu_truncf(float x);
double opemu_trunc(double x);
long double opemu_truncl(long double x);