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      1 /*
      2  * ====================================================
      3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      4  *
      5  * Developed at SunPro, a Sun Microsystems, Inc. business.
      6  * Permission to use, copy, modify, and distribute this
      7  * software is freely granted, provided that this notice
      8  * is preserved.
      9  * ====================================================
     10  */
     11 
     12 /*
     13  * from: @(#)fdlibm.h 5.1 93/09/24
     14  * $FreeBSD: head/lib/msun/src/math_private.h 336663 2018-07-24 10:10:16Z bde $
     15  */
     16 
     17 #ifndef _MATH_PRIVATE_H_
     18 #define	_MATH_PRIVATE_H_
     19 
     20 #include <sys/types.h>
     21 #include <machine/endian.h>
     22 
     23 /*
     24  * The original fdlibm code used statements like:
     25  *	n0 = ((*(int*)&one)>>29)^1;		* index of high word *
     26  *	ix0 = *(n0+(int*)&x);			* high word of x *
     27  *	ix1 = *((1-n0)+(int*)&x);		* low word of x *
     28  * to dig two 32 bit words out of the 64 bit IEEE floating point
     29  * value.  That is non-ANSI, and, moreover, the gcc instruction
     30  * scheduler gets it wrong.  We instead use the following macros.
     31  * Unlike the original code, we determine the endianness at compile
     32  * time, not at run time; I don't see much benefit to selecting
     33  * endianness at run time.
     34  */
     35 
     36 /*
     37  * A union which permits us to convert between a double and two 32 bit
     38  * ints.
     39  */
     40 
     41 #ifdef __arm__
     42 #if defined(__VFP_FP__) || defined(__ARM_EABI__)
     43 #define	IEEE_WORD_ORDER	BYTE_ORDER
     44 #else
     45 #define	IEEE_WORD_ORDER	BIG_ENDIAN
     46 #endif
     47 #else /* __arm__ */
     48 #define	IEEE_WORD_ORDER	BYTE_ORDER
     49 #endif
     50 
     51 /* A union which permits us to convert between a long double and
     52    four 32 bit ints.  */
     53 
     54 #if IEEE_WORD_ORDER == BIG_ENDIAN
     55 
     56 typedef union
     57 {
     58   long double value;
     59   struct {
     60     u_int32_t mswhi;
     61     u_int32_t mswlo;
     62     u_int32_t lswhi;
     63     u_int32_t lswlo;
     64   } parts32;
     65   struct {
     66     u_int64_t msw;
     67     u_int64_t lsw;
     68   } parts64;
     69 } ieee_quad_shape_type;
     70 
     71 #endif
     72 
     73 #if IEEE_WORD_ORDER == LITTLE_ENDIAN
     74 
     75 typedef union
     76 {
     77   long double value;
     78   struct {
     79     u_int32_t lswlo;
     80     u_int32_t lswhi;
     81     u_int32_t mswlo;
     82     u_int32_t mswhi;
     83   } parts32;
     84   struct {
     85     u_int64_t lsw;
     86     u_int64_t msw;
     87   } parts64;
     88 } ieee_quad_shape_type;
     89 
     90 #endif
     91 
     92 #if IEEE_WORD_ORDER == BIG_ENDIAN
     93 
     94 typedef union
     95 {
     96   double value;
     97   struct
     98   {
     99     u_int32_t msw;
    100     u_int32_t lsw;
    101   } parts;
    102   struct
    103   {
    104     u_int64_t w;
    105   } xparts;
    106 } ieee_double_shape_type;
    107 
    108 #endif
    109 
    110 #if IEEE_WORD_ORDER == LITTLE_ENDIAN
    111 
    112 typedef union
    113 {
    114   double value;
    115   struct
    116   {
    117     u_int32_t lsw;
    118     u_int32_t msw;
    119   } parts;
    120   struct
    121   {
    122     u_int64_t w;
    123   } xparts;
    124 } ieee_double_shape_type;
    125 
    126 #endif
    127 
    128 /* Get two 32 bit ints from a double.  */
    129 
    130 #define EXTRACT_WORDS(ix0,ix1,d)				\
    131 do {								\
    132   ieee_double_shape_type ew_u;					\
    133   ew_u.value = (d);						\
    134   (ix0) = ew_u.parts.msw;					\
    135   (ix1) = ew_u.parts.lsw;					\
    136 } while (0)
    137 
    138 /* Get a 64-bit int from a double. */
    139 #define EXTRACT_WORD64(ix,d)					\
    140 do {								\
    141   ieee_double_shape_type ew_u;					\
    142   ew_u.value = (d);						\
    143   (ix) = ew_u.xparts.w;						\
    144 } while (0)
    145 
    146 /* Get the more significant 32 bit int from a double.  */
    147 
    148 #define GET_HIGH_WORD(i,d)					\
    149 do {								\
    150   ieee_double_shape_type gh_u;					\
    151   gh_u.value = (d);						\
    152   (i) = gh_u.parts.msw;						\
    153 } while (0)
    154 
    155 /* Get the less significant 32 bit int from a double.  */
    156 
    157 #define GET_LOW_WORD(i,d)					\
    158 do {								\
    159   ieee_double_shape_type gl_u;					\
    160   gl_u.value = (d);						\
    161   (i) = gl_u.parts.lsw;						\
    162 } while (0)
    163 
    164 /* Set a double from two 32 bit ints.  */
    165 
    166 #define INSERT_WORDS(d,ix0,ix1)					\
    167 do {								\
    168   ieee_double_shape_type iw_u;					\
    169   iw_u.parts.msw = (ix0);					\
    170   iw_u.parts.lsw = (ix1);					\
    171   (d) = iw_u.value;						\
    172 } while (0)
    173 
    174 /* Set a double from a 64-bit int. */
    175 #define INSERT_WORD64(d,ix)					\
    176 do {								\
    177   ieee_double_shape_type iw_u;					\
    178   iw_u.xparts.w = (ix);						\
    179   (d) = iw_u.value;						\
    180 } while (0)
    181 
    182 /* Set the more significant 32 bits of a double from an int.  */
    183 
    184 #define SET_HIGH_WORD(d,v)					\
    185 do {								\
    186   ieee_double_shape_type sh_u;					\
    187   sh_u.value = (d);						\
    188   sh_u.parts.msw = (v);						\
    189   (d) = sh_u.value;						\
    190 } while (0)
    191 
    192 /* Set the less significant 32 bits of a double from an int.  */
    193 
    194 #define SET_LOW_WORD(d,v)					\
    195 do {								\
    196   ieee_double_shape_type sl_u;					\
    197   sl_u.value = (d);						\
    198   sl_u.parts.lsw = (v);						\
    199   (d) = sl_u.value;						\
    200 } while (0)
    201 
    202 /*
    203  * A union which permits us to convert between a float and a 32 bit
    204  * int.
    205  */
    206 
    207 typedef union
    208 {
    209   float value;
    210   /* FIXME: Assumes 32 bit int.  */
    211   unsigned int word;
    212 } ieee_float_shape_type;
    213 
    214 /* Get a 32 bit int from a float.  */
    215 
    216 #define GET_FLOAT_WORD(i,d)					\
    217 do {								\
    218   ieee_float_shape_type gf_u;					\
    219   gf_u.value = (d);						\
    220   (i) = gf_u.word;						\
    221 } while (0)
    222 
    223 /* Set a float from a 32 bit int.  */
    224 
    225 #define SET_FLOAT_WORD(d,i)					\
    226 do {								\
    227   ieee_float_shape_type sf_u;					\
    228   sf_u.word = (i);						\
    229   (d) = sf_u.value;						\
    230 } while (0)
    231 
    232 /*
    233  * Get expsign and mantissa as 16 bit and 64 bit ints from an 80 bit long
    234  * double.
    235  */
    236 
    237 #define	EXTRACT_LDBL80_WORDS(ix0,ix1,d)				\
    238 do {								\
    239   union IEEEl2bits ew_u;					\
    240   ew_u.e = (d);							\
    241   (ix0) = ew_u.xbits.expsign;					\
    242   (ix1) = ew_u.xbits.man;					\
    243 } while (0)
    244 
    245 /*
    246  * Get expsign and mantissa as one 16 bit and two 64 bit ints from a 128 bit
    247  * long double.
    248  */
    249 
    250 #define	EXTRACT_LDBL128_WORDS(ix0,ix1,ix2,d)			\
    251 do {								\
    252   union IEEEl2bits ew_u;					\
    253   ew_u.e = (d);							\
    254   (ix0) = ew_u.xbits.expsign;					\
    255   (ix1) = ew_u.xbits.manh;					\
    256   (ix2) = ew_u.xbits.manl;					\
    257 } while (0)
    258 
    259 /* Get expsign as a 16 bit int from a long double.  */
    260 
    261 #define	GET_LDBL_EXPSIGN(i,d)					\
    262 do {								\
    263   union IEEEl2bits ge_u;					\
    264   ge_u.e = (d);							\
    265   (i) = ge_u.xbits.expsign;					\
    266 } while (0)
    267 
    268 /*
    269  * Set an 80 bit long double from a 16 bit int expsign and a 64 bit int
    270  * mantissa.
    271  */
    272 
    273 #define	INSERT_LDBL80_WORDS(d,ix0,ix1)				\
    274 do {								\
    275   union IEEEl2bits iw_u;					\
    276   iw_u.xbits.expsign = (ix0);					\
    277   iw_u.xbits.man = (ix1);					\
    278   (d) = iw_u.e;							\
    279 } while (0)
    280 
    281 /*
    282  * Set a 128 bit long double from a 16 bit int expsign and two 64 bit ints
    283  * comprising the mantissa.
    284  */
    285 
    286 #define	INSERT_LDBL128_WORDS(d,ix0,ix1,ix2)			\
    287 do {								\
    288   union IEEEl2bits iw_u;					\
    289   iw_u.xbits.expsign = (ix0);					\
    290   iw_u.xbits.manh = (ix1);					\
    291   iw_u.xbits.manl = (ix2);					\
    292   (d) = iw_u.e;							\
    293 } while (0)
    294 
    295 /* Set expsign of a long double from a 16 bit int.  */
    296 
    297 #define	SET_LDBL_EXPSIGN(d,v)					\
    298 do {								\
    299   union IEEEl2bits se_u;					\
    300   se_u.e = (d);							\
    301   se_u.xbits.expsign = (v);					\
    302   (d) = se_u.e;							\
    303 } while (0)
    304 
    305 #ifdef __i386__
    306 /* Long double constants are broken on i386. */
    307 #define	LD80C(m, ex, v) {						\
    308 	.xbits.man = __CONCAT(m, ULL),					\
    309 	.xbits.expsign = (0x3fff + (ex)) | ((v) < 0 ? 0x8000 : 0),	\
    310 }
    311 #else
    312 /* The above works on non-i386 too, but we use this to check v. */
    313 #define	LD80C(m, ex, v)	{ .e = (v), }
    314 #endif
    315 
    316 #ifdef FLT_EVAL_METHOD
    317 /*
    318  * Attempt to get strict C99 semantics for assignment with non-C99 compilers.
    319  */
    320 #if FLT_EVAL_METHOD == 0 || __GNUC__ == 0
    321 #define	STRICT_ASSIGN(type, lval, rval)	((lval) = (rval))
    322 #else
    323 #define	STRICT_ASSIGN(type, lval, rval) do {	\
    324 	volatile type __lval;			\
    325 						\
    326 	if (sizeof(type) >= sizeof(long double))	\
    327 		(lval) = (rval);		\
    328 	else {					\
    329 		__lval = (rval);		\
    330 		(lval) = __lval;		\
    331 	}					\
    332 } while (0)
    333 #endif
    334 #endif /* FLT_EVAL_METHOD */
    335 
    336 /* Support switching the mode to FP_PE if necessary. */
    337 #if defined(__i386__) && !defined(NO_FPSETPREC)
    338 #define	ENTERI() ENTERIT(long double)
    339 #define	ENTERIT(returntype)			\
    340 	returntype __retval;			\
    341 	fp_prec_t __oprec;			\
    342 						\
    343 	if ((__oprec = fpgetprec()) != FP_PE)	\
    344 		fpsetprec(FP_PE)
    345 #define	RETURNI(x) do {				\
    346 	__retval = (x);				\
    347 	if (__oprec != FP_PE)			\
    348 		fpsetprec(__oprec);		\
    349 	RETURNF(__retval);			\
    350 } while (0)
    351 #define	ENTERV()				\
    352 	fp_prec_t __oprec;			\
    353 						\
    354 	if ((__oprec = fpgetprec()) != FP_PE)	\
    355 		fpsetprec(FP_PE)
    356 #define	RETURNV() do {				\
    357 	if (__oprec != FP_PE)			\
    358 		fpsetprec(__oprec);		\
    359 	return;			\
    360 } while (0)
    361 #else
    362 #define	ENTERI()
    363 #define	ENTERIT(x)
    364 #define	RETURNI(x)	RETURNF(x)
    365 #define	ENTERV()
    366 #define	RETURNV()	return
    367 #endif
    368 
    369 /* Default return statement if hack*_t() is not used. */
    370 #define      RETURNF(v)      return (v)
    371 
    372 /*
    373  * 2sum gives the same result as 2sumF without requiring |a| >= |b| or
    374  * a == 0, but is slower.
    375  */
    376 #define	_2sum(a, b) do {	\
    377 	__typeof(a) __s, __w;	\
    378 				\
    379 	__w = (a) + (b);	\
    380 	__s = __w - (a);	\
    381 	(b) = ((a) - (__w - __s)) + ((b) - __s); \
    382 	(a) = __w;		\
    383 } while (0)
    384 
    385 /*
    386  * 2sumF algorithm.
    387  *
    388  * "Normalize" the terms in the infinite-precision expression a + b for
    389  * the sum of 2 floating point values so that b is as small as possible
    390  * relative to 'a'.  (The resulting 'a' is the value of the expression in
    391  * the same precision as 'a' and the resulting b is the rounding error.)
    392  * |a| must be >= |b| or 0, b's type must be no larger than 'a's type, and
    393  * exponent overflow or underflow must not occur.  This uses a Theorem of
    394  * Dekker (1971).  See Knuth (1981) 4.2.2 Theorem C.  The name "TwoSum"
    395  * is apparently due to Skewchuk (1997).
    396  *
    397  * For this to always work, assignment of a + b to 'a' must not retain any
    398  * extra precision in a + b.  This is required by C standards but broken
    399  * in many compilers.  The brokenness cannot be worked around using
    400  * STRICT_ASSIGN() like we do elsewhere, since the efficiency of this
    401  * algorithm would be destroyed by non-null strict assignments.  (The
    402  * compilers are correct to be broken -- the efficiency of all floating
    403  * point code calculations would be destroyed similarly if they forced the
    404  * conversions.)
    405  *
    406  * Fortunately, a case that works well can usually be arranged by building
    407  * any extra precision into the type of 'a' -- 'a' should have type float_t,
    408  * double_t or long double.  b's type should be no larger than 'a's type.
    409  * Callers should use these types with scopes as large as possible, to
    410  * reduce their own extra-precision and efficiciency problems.  In
    411  * particular, they shouldn't convert back and forth just to call here.
    412  */
    413 #ifdef DEBUG
    414 #define	_2sumF(a, b) do {				\
    415 	__typeof(a) __w;				\
    416 	volatile __typeof(a) __ia, __ib, __r, __vw;	\
    417 							\
    418 	__ia = (a);					\
    419 	__ib = (b);					\
    420 	assert(__ia == 0 || fabsl(__ia) >= fabsl(__ib));	\
    421 							\
    422 	__w = (a) + (b);				\
    423 	(b) = ((a) - __w) + (b);			\
    424 	(a) = __w;					\
    425 							\
    426 	/* The next 2 assertions are weak if (a) is already long double. */ \
    427 	assert((long double)__ia + __ib == (long double)(a) + (b));	\
    428 	__vw = __ia + __ib;				\
    429 	__r = __ia - __vw;				\
    430 	__r += __ib;					\
    431 	assert(__vw == (a) && __r == (b));		\
    432 } while (0)
    433 #else /* !DEBUG */
    434 #define	_2sumF(a, b) do {	\
    435 	__typeof(a) __w;	\
    436 				\
    437 	__w = (a) + (b);	\
    438 	(b) = ((a) - __w) + (b); \
    439 	(a) = __w;		\
    440 } while (0)
    441 #endif /* DEBUG */
    442 
    443 /*
    444  * Set x += c, where x is represented in extra precision as a + b.
    445  * x must be sufficiently normalized and sufficiently larger than c,
    446  * and the result is then sufficiently normalized.
    447  *
    448  * The details of ordering are that |a| must be >= |c| (so that (a, c)
    449  * can be normalized without extra work to swap 'a' with c).  The details of
    450  * the normalization are that b must be small relative to the normalized 'a'.
    451  * Normalization of (a, c) makes the normalized c tiny relative to the
    452  * normalized a, so b remains small relative to 'a' in the result.  However,
    453  * b need not ever be tiny relative to 'a'.  For example, b might be about
    454  * 2**20 times smaller than 'a' to give about 20 extra bits of precision.
    455  * That is usually enough, and adding c (which by normalization is about
    456  * 2**53 times smaller than a) cannot change b significantly.  However,
    457  * cancellation of 'a' with c in normalization of (a, c) may reduce 'a'
    458  * significantly relative to b.  The caller must ensure that significant
    459  * cancellation doesn't occur, either by having c of the same sign as 'a',
    460  * or by having |c| a few percent smaller than |a|.  Pre-normalization of
    461  * (a, b) may help.
    462  *
    463  * This is is a variant of an algorithm of Kahan (see Knuth (1981) 4.2.2
    464  * exercise 19).  We gain considerable efficiency by requiring the terms to
    465  * be sufficiently normalized and sufficiently increasing.
    466  */
    467 #define	_3sumF(a, b, c) do {	\
    468 	__typeof(a) __tmp;	\
    469 				\
    470 	__tmp = (c);		\
    471 	_2sumF(__tmp, (a));	\
    472 	(b) += (a);		\
    473 	(a) = __tmp;		\
    474 } while (0)
    475 
    476 /*
    477  * Common routine to process the arguments to nan(), nanf(), and nanl().
    478  */
    479 void _scan_nan(uint32_t *__words, int __num_words, const char *__s);
    480 
    481 /*
    482  * Mix 0, 1 or 2 NaNs.  First add 0 to each arg.  This normally just turns
    483  * signaling NaNs into quiet NaNs by setting a quiet bit.  We do this
    484  * because we want to never return a signaling NaN, and also because we
    485  * don't want the quiet bit to affect the result.  Then mix the converted
    486  * args using the specified operation.
    487  *
    488  * When one arg is NaN, the result is typically that arg quieted.  When both
    489  * args are NaNs, the result is typically the quietening of the arg whose
    490  * mantissa is largest after quietening.  When neither arg is NaN, the
    491  * result may be NaN because it is indeterminate, or finite for subsequent
    492  * construction of a NaN as the indeterminate 0.0L/0.0L.
    493  *
    494  * Technical complications: the result in bits after rounding to the final
    495  * precision might depend on the runtime precision and/or on compiler
    496  * optimizations, especially when different register sets are used for
    497  * different precisions.  Try to make the result not depend on at least the
    498  * runtime precision by always doing the main mixing step in long double
    499  * precision.  Try to reduce dependencies on optimizations by adding the
    500  * the 0's in different precisions (unless everything is in long double
    501  * precision).
    502  */
    503 #define	nan_mix(x, y)		(nan_mix_op((x), (y), +))
    504 #define	nan_mix_op(x, y, op)	(((x) + 0.0L) op ((y) + 0))
    505 
    506 #ifdef _COMPLEX_H
    507 
    508 /*
    509  * C99 specifies that complex numbers have the same representation as
    510  * an array of two elements, where the first element is the real part
    511  * and the second element is the imaginary part.
    512  */
    513 typedef union {
    514 	float complex f;
    515 	float a[2];
    516 } float_complex;
    517 typedef union {
    518 	double complex f;
    519 	double a[2];
    520 } double_complex;
    521 typedef union {
    522 	long double complex f;
    523 	long double a[2];
    524 } long_double_complex;
    525 #define	REALPART(z)	((z).a[0])
    526 #define	IMAGPART(z)	((z).a[1])
    527 
    528 /*
    529  * Inline functions that can be used to construct complex values.
    530  *
    531  * The C99 standard intends x+I*y to be used for this, but x+I*y is
    532  * currently unusable in general since gcc introduces many overflow,
    533  * underflow, sign and efficiency bugs by rewriting I*y as
    534  * (0.0+I)*(y+0.0*I) and laboriously computing the full complex product.
    535  * In particular, I*Inf is corrupted to NaN+I*Inf, and I*-0 is corrupted
    536  * to -0.0+I*0.0.
    537  *
    538  * The C11 standard introduced the macros CMPLX(), CMPLXF() and CMPLXL()
    539  * to construct complex values.  Compilers that conform to the C99
    540  * standard require the following functions to avoid the above issues.
    541  */
    542 
    543 #ifndef CMPLXF
    544 static __inline float complex
    545 CMPLXF(float x, float y)
    546 {
    547 	float_complex z;
    548 
    549 	REALPART(z) = x;
    550 	IMAGPART(z) = y;
    551 	return (z.f);
    552 }
    553 #endif
    554 
    555 #ifndef CMPLX
    556 static __inline double complex
    557 CMPLX(double x, double y)
    558 {
    559 	double_complex z;
    560 
    561 	REALPART(z) = x;
    562 	IMAGPART(z) = y;
    563 	return (z.f);
    564 }
    565 #endif
    566 
    567 #ifndef CMPLXL
    568 static __inline long double complex
    569 CMPLXL(long double x, long double y)
    570 {
    571 	long_double_complex z;
    572 
    573 	REALPART(z) = x;
    574 	IMAGPART(z) = y;
    575 	return (z.f);
    576 }
    577 #endif
    578 
    579 #endif /* _COMPLEX_H */
    580 
    581 /*
    582  * The rnint() family rounds to the nearest integer for a restricted range
    583  * range of args (up to about 2**MANT_DIG).  We assume that the current
    584  * rounding mode is FE_TONEAREST so that this can be done efficiently.
    585  * Extra precision causes more problems in practice, and we only centralize
    586  * this here to reduce those problems, and have not solved the efficiency
    587  * problems.  The exp2() family uses a more delicate version of this that
    588  * requires extracting bits from the intermediate value, so it is not
    589  * centralized here and should copy any solution of the efficiency problems.
    590  */
    591 
    592 static inline double
    593 rnint(__double_t x)
    594 {
    595 	/*
    596 	 * This casts to double to kill any extra precision.  This depends
    597 	 * on the cast being applied to a double_t to avoid compiler bugs
    598 	 * (this is a cleaner version of STRICT_ASSIGN()).  This is
    599 	 * inefficient if there actually is extra precision, but is hard
    600 	 * to improve on.  We use double_t in the API to minimise conversions
    601 	 * for just calling here.  Note that we cannot easily change the
    602 	 * magic number to the one that works directly with double_t, since
    603 	 * the rounding precision is variable at runtime on x86 so the
    604 	 * magic number would need to be variable.  Assuming that the
    605 	 * rounding precision is always the default is too fragile.  This
    606 	 * and many other complications will move when the default is
    607 	 * changed to FP_PE.
    608 	 */
    609 	return ((double)(x + 0x1.8p52) - 0x1.8p52);
    610 }
    611 
    612 static inline float
    613 rnintf(__float_t x)
    614 {
    615 	/*
    616 	 * As for rnint(), except we could just call that to handle the
    617 	 * extra precision case, usually without losing efficiency.
    618 	 */
    619 	return ((float)(x + 0x1.8p23F) - 0x1.8p23F);
    620 }
    621 
    622 #ifdef LDBL_MANT_DIG
    623 /*
    624  * The complications for extra precision are smaller for rnintl() since it
    625  * can safely assume that the rounding precision has been increased from
    626  * its default to FP_PE on x86.  We don't exploit that here to get small
    627  * optimizations from limiting the rangle to double.  We just need it for
    628  * the magic number to work with long doubles.  ld128 callers should use
    629  * rnint() instead of this if possible.  ld80 callers should prefer
    630  * rnintl() since for amd64 this avoids swapping the register set, while
    631  * for i386 it makes no difference (assuming FP_PE), and for other arches
    632  * it makes little difference.
    633  */
    634 static inline long double
    635 rnintl(long double x)
    636 {
    637 	return (x + __CONCAT(0x1.8p, LDBL_MANT_DIG) / 2 -
    638 	    __CONCAT(0x1.8p, LDBL_MANT_DIG) / 2);
    639 }
    640 #endif /* LDBL_MANT_DIG */
    641 
    642 /*
    643  * irint() and i64rint() give the same result as casting to their integer
    644  * return type provided their arg is a floating point integer.  They can
    645  * sometimes be more efficient because no rounding is required.
    646  */
    647 #if (defined(amd64) || defined(__i386__)) && defined(__GNUCLIKE_ASM)
    648 #define	irint(x)						\
    649     (sizeof(x) == sizeof(float) &&				\
    650     sizeof(__float_t) == sizeof(long double) ? irintf(x) :	\
    651     sizeof(x) == sizeof(double) &&				\
    652     sizeof(__double_t) == sizeof(long double) ? irintd(x) :	\
    653     sizeof(x) == sizeof(long double) ? irintl(x) : (int)(x))
    654 #else
    655 #define	irint(x)	((int)(x))
    656 #endif
    657 
    658 #define	i64rint(x)	((int64_t)(x))	/* only needed for ld128 so not opt. */
    659 
    660 #if defined(__i386__) && defined(__GNUCLIKE_ASM)
    661 static __inline int
    662 irintf(float x)
    663 {
    664 	int n;
    665 
    666 	__asm("fistl %0" : "=m" (n) : "t" (x));
    667 	return (n);
    668 }
    669 
    670 static __inline int
    671 irintd(double x)
    672 {
    673 	int n;
    674 
    675 	__asm("fistl %0" : "=m" (n) : "t" (x));
    676 	return (n);
    677 }
    678 #endif
    679 
    680 #if (defined(__amd64__) || defined(__i386__)) && defined(__GNUCLIKE_ASM)
    681 static __inline int
    682 irintl(long double x)
    683 {
    684 	int n;
    685 
    686 	__asm("fistl %0" : "=m" (n) : "t" (x));
    687 	return (n);
    688 }
    689 #endif
    690 
    691 #ifdef DEBUG
    692 #if defined(__amd64__) || defined(__i386__)
    693 #define	breakpoint()	asm("int $3")
    694 #else
    695 #include <signal.h>
    696 
    697 #define	breakpoint()	raise(SIGTRAP)
    698 #endif
    699 #endif
    700 
    701 /* Write a pari script to test things externally. */
    702 #ifdef DOPRINT
    703 #include <stdio.h>
    704 
    705 #ifndef DOPRINT_SWIZZLE
    706 #define	DOPRINT_SWIZZLE		0
    707 #endif
    708 
    709 #ifdef DOPRINT_LD80
    710 
    711 #define	DOPRINT_START(xp) do {						\
    712 	uint64_t __lx;							\
    713 	uint16_t __hx;							\
    714 									\
    715 	/* Hack to give more-problematic args. */			\
    716 	EXTRACT_LDBL80_WORDS(__hx, __lx, *xp);				\
    717 	__lx ^= DOPRINT_SWIZZLE;					\
    718 	INSERT_LDBL80_WORDS(*xp, __hx, __lx);				\
    719 	printf("x = %.21Lg; ", (long double)*xp);			\
    720 } while (0)
    721 #define	DOPRINT_END1(v)							\
    722 	printf("y = %.21Lg; z = 0; show(x, y, z);\n", (long double)(v))
    723 #define	DOPRINT_END2(hi, lo)						\
    724 	printf("y = %.21Lg; z = %.21Lg; show(x, y, z);\n",		\
    725 	    (long double)(hi), (long double)(lo))
    726 
    727 #elif defined(DOPRINT_D64)
    728 
    729 #define	DOPRINT_START(xp) do {						\
    730 	uint32_t __hx, __lx;						\
    731 									\
    732 	EXTRACT_WORDS(__hx, __lx, *xp);					\
    733 	__lx ^= DOPRINT_SWIZZLE;					\
    734 	INSERT_WORDS(*xp, __hx, __lx);					\
    735 	printf("x = %.21Lg; ", (long double)*xp);			\
    736 } while (0)
    737 #define	DOPRINT_END1(v)							\
    738 	printf("y = %.21Lg; z = 0; show(x, y, z);\n", (long double)(v))
    739 #define	DOPRINT_END2(hi, lo)						\
    740 	printf("y = %.21Lg; z = %.21Lg; show(x, y, z);\n",		\
    741 	    (long double)(hi), (long double)(lo))
    742 
    743 #elif defined(DOPRINT_F32)
    744 
    745 #define	DOPRINT_START(xp) do {						\
    746 	uint32_t __hx;							\
    747 									\
    748 	GET_FLOAT_WORD(__hx, *xp);					\
    749 	__hx ^= DOPRINT_SWIZZLE;					\
    750 	SET_FLOAT_WORD(*xp, __hx);					\
    751 	printf("x = %.21Lg; ", (long double)*xp);			\
    752 } while (0)
    753 #define	DOPRINT_END1(v)							\
    754 	printf("y = %.21Lg; z = 0; show(x, y, z);\n", (long double)(v))
    755 #define	DOPRINT_END2(hi, lo)						\
    756 	printf("y = %.21Lg; z = %.21Lg; show(x, y, z);\n",		\
    757 	    (long double)(hi), (long double)(lo))
    758 
    759 #else /* !DOPRINT_LD80 && !DOPRINT_D64 (LD128 only) */
    760 
    761 #ifndef DOPRINT_SWIZZLE_HIGH
    762 #define	DOPRINT_SWIZZLE_HIGH	0
    763 #endif
    764 
    765 #define	DOPRINT_START(xp) do {						\
    766 	uint64_t __lx, __llx;						\
    767 	uint16_t __hx;							\
    768 									\
    769 	EXTRACT_LDBL128_WORDS(__hx, __lx, __llx, *xp);			\
    770 	__llx ^= DOPRINT_SWIZZLE;					\
    771 	__lx ^= DOPRINT_SWIZZLE_HIGH;					\
    772 	INSERT_LDBL128_WORDS(*xp, __hx, __lx, __llx);			\
    773 	printf("x = %.36Lg; ", (long double)*xp);					\
    774 } while (0)
    775 #define	DOPRINT_END1(v)							\
    776 	printf("y = %.36Lg; z = 0; show(x, y, z);\n", (long double)(v))
    777 #define	DOPRINT_END2(hi, lo)						\
    778 	printf("y = %.36Lg; z = %.36Lg; show(x, y, z);\n",		\
    779 	    (long double)(hi), (long double)(lo))
    780 
    781 #endif /* DOPRINT_LD80 */
    782 
    783 #else /* !DOPRINT */
    784 #define	DOPRINT_START(xp)
    785 #define	DOPRINT_END1(v)
    786 #define	DOPRINT_END2(hi, lo)
    787 #endif /* DOPRINT */
    788 
    789 #define	RETURNP(x) do {			\
    790 	DOPRINT_END1(x);		\
    791 	RETURNF(x);			\
    792 } while (0)
    793 #define	RETURNPI(x) do {		\
    794 	DOPRINT_END1(x);		\
    795 	RETURNI(x);			\
    796 } while (0)
    797 #define	RETURN2P(x, y) do {		\
    798 	DOPRINT_END2((x), (y));		\
    799 	RETURNF((x) + (y));		\
    800 } while (0)
    801 #define	RETURN2PI(x, y) do {		\
    802 	DOPRINT_END2((x), (y));		\
    803 	RETURNI((x) + (y));		\
    804 } while (0)
    805 #ifdef STRUCT_RETURN
    806 #define	RETURNSP(rp) do {		\
    807 	if (!(rp)->lo_set)		\
    808 		RETURNP((rp)->hi);	\
    809 	RETURN2P((rp)->hi, (rp)->lo);	\
    810 } while (0)
    811 #define	RETURNSPI(rp) do {		\
    812 	if (!(rp)->lo_set)		\
    813 		RETURNPI((rp)->hi);	\
    814 	RETURN2PI((rp)->hi, (rp)->lo);	\
    815 } while (0)
    816 #endif
    817 #define	SUM2P(x, y) ({			\
    818 	const __typeof (x) __x = (x);	\
    819 	const __typeof (y) __y = (y);	\
    820 					\
    821 	DOPRINT_END2(__x, __y);		\
    822 	__x + __y;			\
    823 })
    824 
    825 /*
    826  * ieee style elementary functions
    827  *
    828  * We rename functions here to improve other sources' diffability
    829  * against fdlibm.
    830  */
    831 #define	__ieee754_sqrt	sqrt
    832 #define	__ieee754_acos	acos
    833 #define	__ieee754_acosh	acosh
    834 #define	__ieee754_log	log
    835 #define	__ieee754_log2	log2
    836 #define	__ieee754_atanh	atanh
    837 #define	__ieee754_asin	asin
    838 #define	__ieee754_atan2	atan2
    839 #define	__ieee754_exp	exp
    840 #define	__ieee754_cosh	cosh
    841 #define	__ieee754_fmod	fmod
    842 #define	__ieee754_pow	pow
    843 #define	__ieee754_lgamma lgamma
    844 #define	__ieee754_gamma	gamma
    845 #define	__ieee754_lgamma_r lgamma_r
    846 #define	__ieee754_gamma_r gamma_r
    847 #define	__ieee754_log10	log10
    848 #define	__ieee754_sinh	sinh
    849 #define	__ieee754_hypot	hypot
    850 #define	__ieee754_j0	j0
    851 #define	__ieee754_j1	j1
    852 #define	__ieee754_y0	y0
    853 #define	__ieee754_y1	y1
    854 #define	__ieee754_jn	jn
    855 #define	__ieee754_yn	yn
    856 #define	__ieee754_remainder remainder
    857 #define	__ieee754_scalb	scalb
    858 #define	__ieee754_sqrtf	sqrtf
    859 #define	__ieee754_acosf	acosf
    860 #define	__ieee754_acoshf acoshf
    861 #define	__ieee754_logf	logf
    862 #define	__ieee754_atanhf atanhf
    863 #define	__ieee754_asinf	asinf
    864 #define	__ieee754_atan2f atan2f
    865 #define	__ieee754_expf	expf
    866 #define	__ieee754_coshf	coshf
    867 #define	__ieee754_fmodf	fmodf
    868 #define	__ieee754_powf	powf
    869 #define	__ieee754_lgammaf lgammaf
    870 #define	__ieee754_gammaf gammaf
    871 #define	__ieee754_lgammaf_r lgammaf_r
    872 #define	__ieee754_gammaf_r gammaf_r
    873 #define	__ieee754_log10f log10f
    874 #define	__ieee754_log2f log2f
    875 #define	__ieee754_sinhf	sinhf
    876 #define	__ieee754_hypotf hypotf
    877 #define	__ieee754_j0f	j0f
    878 #define	__ieee754_j1f	j1f
    879 #define	__ieee754_y0f	y0f
    880 #define	__ieee754_y1f	y1f
    881 #define	__ieee754_jnf	jnf
    882 #define	__ieee754_ynf	ynf
    883 #define	__ieee754_remainderf remainderf
    884 #define	__ieee754_scalbf scalbf
    885 
    886 /* fdlibm kernel function */
    887 int	__kernel_rem_pio2(double*,double*,int,int,int);
    888 
    889 /* double precision kernel functions */
    890 #ifndef INLINE_REM_PIO2
    891 int	__ieee754_rem_pio2(double,double*);
    892 #endif
    893 double	__kernel_sin(double,double,int);
    894 double	__kernel_cos(double,double);
    895 double	__kernel_tan(double,double,int);
    896 double	__ldexp_exp(double,int);
    897 #ifdef _COMPLEX_H
    898 double complex __ldexp_cexp(double complex,int);
    899 #endif
    900 
    901 /* float precision kernel functions */
    902 #ifndef INLINE_REM_PIO2F
    903 int	__ieee754_rem_pio2f(float,double*);
    904 #endif
    905 #ifndef INLINE_KERNEL_SINDF
    906 float	__kernel_sindf(double);
    907 #endif
    908 #ifndef INLINE_KERNEL_COSDF
    909 float	__kernel_cosdf(double);
    910 #endif
    911 #ifndef INLINE_KERNEL_TANDF
    912 float	__kernel_tandf(double,int);
    913 #endif
    914 float	__ldexp_expf(float,int);
    915 #ifdef _COMPLEX_H
    916 float complex __ldexp_cexpf(float complex,int);
    917 #endif
    918 
    919 /* long double precision kernel functions */
    920 long double __kernel_sinl(long double, long double, int);
    921 long double __kernel_cosl(long double, long double);
    922 long double __kernel_tanl(long double, long double, int);
    923 
    924 #endif /* !_MATH_PRIVATE_H_ */
    925