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/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include <inttypes.h>
#include <float.h>
typedef unsigned int u_int32_t;
typedef union
{
double value;
struct
{
u_int32_t lsw;
u_int32_t msw;
} parts;
} ieee_double_shape_type;
typedef union {
float value;
u_int32_t word;
} ieee_float_shape_type;
/* Get two 32 bit ints from a 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)
/* Get the most significant 32 bit int from a double. */
#define GET_HIGH_WORD(i,d) \
do { \
ieee_double_shape_type gh_u; \
gh_u.value = (d); \
(i) = gh_u.parts.msw; \
} while (0)
/* Get the less significant 32 bit int from a double. */
#define GET_LOW_WORD(i,d) \
do { \
ieee_double_shape_type gl_u; \
gl_u.value = (d); \
(i) = gl_u.parts.lsw; \
} while (0)
/* Set a double from two 32 bit ints. */
#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)
/* Set the more significant 32 bits of a double from an int. */
#define SET_HIGH_WORD(d,v) \
do { \
ieee_double_shape_type sh_u; \
sh_u.value = (d); \
sh_u.parts.msw = (v); \
(d) = sh_u.value; \
} while (0)
/* Set the less significant 32 bits of a double from an int. */
#define SET_LOW_WORD(d,v) \
do { \
ieee_double_shape_type sl_u; \
sl_u.value = (d); \
sl_u.parts.lsw = (v); \
(d) = sl_u.value; \
} while (0)
#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 gf_u; \
gf_u.word = (i); \
(d) = gf_u.value; \
} while(0)
#ifdef FLT_EVAL_METHOD
/*
* Attempt to get strict C99 semantics for assignment with non-C99 compilers.
*/
#if FLT_EVAL_METHOD == 0 || __GNUC__ == 0
#define STRICT_ASSIGN(type, lval, rval) ((lval) = (rval))
#else
#define STRICT_ASSIGN(type, lval, rval) do { \
volatile type __lval; \
\
if (sizeof(type) >= sizeof(long double)) \
(lval) = (rval); \
else { \
__lval = (rval); \
(lval) = __lval; \
} \
} while (0)
#endif
#endif /* FLT_EVAL_METHOD */
/*
* Mix 0, 1 or 2 NaNs. First add 0 to each arg. This normally just turns
* signaling NaNs into quiet NaNs by setting a quiet bit. We do this
* because we want to never return a signaling NaN, and also because we
* don't want the quiet bit to affect the result. Then mix the converted
* args using the specified operation.
*
* When one arg is NaN, the result is typically that arg quieted. When both
* args are NaNs, the result is typically the quietening of the arg whose
* mantissa is largest after quietening. When neither arg is NaN, the
* result may be NaN because it is indeterminate, or finite for subsequent
* construction of a NaN as the indeterminate 0.0L/0.0L.
*
* Technical complications: the result in bits after rounding to the final
* precision might depend on the runtime precision and/or on compiler
* optimizations, especially when different register sets are used for
* different precisions. Try to make the result not depend on at least the
* runtime precision by always doing the main mixing step in long double
* precision. Try to reduce dependencies on optimizations by adding the
* the 0's in different precisions (unless everything is in long double
* precision).
*/
#define nan_mix(x, y) (nan_mix_op((x), (y), +))
#define nan_mix_op(x, y, op) (((x) + 0.0L) op ((y) + 0))
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