1 /****************************************************************
3 The author of this software is David M. Gay.
5 Copyright (C) 1998-2000 by Lucent Technologies
8 Permission to use, copy, modify, and distribute this software and
9 its documentation for any purpose and without fee is hereby
10 granted, provided that the above copyright notice appear in all
11 copies and that both that the copyright notice and this
12 permission notice and warranty disclaimer appear in supporting
13 documentation, and that the name of Lucent or any of its entities
14 not be used in advertising or publicity pertaining to
15 distribution of the software without specific, written prior
18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
27 ****************************************************************/
29 /* $FreeBSD: head/contrib/gdtoa/gdtoaimp.h 227753 2011-11-20 14:45:42Z theraven $ */
31 /* This is a variation on dtoa.c that converts arbitary binary
32 floating-point formats to and from decimal notation. It uses
33 double-precision arithmetic internally, so there are still
34 various #ifdefs that adapt the calculations to the native
35 double-precision arithmetic (any of IEEE, VAX D_floating,
36 or IBM mainframe arithmetic).
38 Please send bug reports to David M. Gay (dmg at acm dot org,
39 with " at " changed at "@" and " dot " changed to ".").
42 /* On a machine with IEEE extended-precision registers, it is
43 * necessary to specify double-precision (53-bit) rounding precision
44 * before invoking strtod or dtoa. If the machine uses (the equivalent
45 * of) Intel 80x87 arithmetic, the call
46 * _control87(PC_53, MCW_PC);
47 * does this with many compilers. Whether this or another call is
48 * appropriate depends on the compiler; for this to work, it may be
49 * necessary to #include "float.h" or another system-dependent header
53 /* strtod for IEEE-, VAX-, and IBM-arithmetic machines.
55 * This strtod returns a nearest machine number to the input decimal
56 * string (or sets errno to ERANGE). With IEEE arithmetic, ties are
57 * broken by the IEEE round-even rule. Otherwise ties are broken by
58 * biased rounding (add half and chop).
60 * Inspired loosely by William D. Clinger's paper "How to Read Floating
61 * Point Numbers Accurately" [Proc. ACM SIGPLAN '90, pp. 112-126].
65 * 1. We only require IEEE, IBM, or VAX double-precision
66 * arithmetic (not IEEE double-extended).
67 * 2. We get by with floating-point arithmetic in a case that
68 * Clinger missed -- when we're computing d * 10^n
69 * for a small integer d and the integer n is not too
70 * much larger than 22 (the maximum integer k for which
71 * we can represent 10^k exactly), we may be able to
72 * compute (d*10^k) * 10^(e-k) with just one roundoff.
73 * 3. Rather than a bit-at-a-time adjustment of the binary
74 * result in the hard case, we use floating-point
75 * arithmetic to determine the adjustment to within
76 * one bit; only in really hard cases do we need to
77 * compute a second residual.
78 * 4. Because of 3., we don't need a large table of powers of 10
79 * for ten-to-e (just some small tables, e.g. of 10^k
84 * #define IEEE_8087 for IEEE-arithmetic machines where the least
85 * significant byte has the lowest address.
86 * #define IEEE_MC68k for IEEE-arithmetic machines where the most
87 * significant byte has the lowest address.
88 * #define Long int on machines with 32-bit ints and 64-bit longs.
89 * #define Sudden_Underflow for IEEE-format machines without gradual
90 * underflow (i.e., that flush to zero on underflow).
91 * #define IBM for IBM mainframe-style floating-point arithmetic.
92 * #define VAX for VAX-style floating-point arithmetic (D_floating).
93 * #define No_leftright to omit left-right logic in fast floating-point
94 * computation of dtoa.
95 * #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3.
96 * #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines
97 * that use extended-precision instructions to compute rounded
98 * products and quotients) with IBM.
99 * #define ROUND_BIASED for IEEE-format with biased rounding and arithmetic
100 * that rounds toward +Infinity.
101 * #define ROUND_BIASED_without_Round_Up for IEEE-format with biased
102 * rounding when the underlying floating-point arithmetic uses
103 * unbiased rounding. This prevent using ordinary floating-point
104 * arithmetic when the result could be computed with one rounding error.
105 * #define Inaccurate_Divide for IEEE-format with correctly rounded
106 * products but inaccurate quotients, e.g., for Intel i860.
107 * #define NO_LONG_LONG on machines that do not have a "long long"
108 * integer type (of >= 64 bits). On such machines, you can
109 * #define Just_16 to store 16 bits per 32-bit Long when doing
110 * high-precision integer arithmetic. Whether this speeds things
111 * up or slows things down depends on the machine and the number
112 * being converted. If long long is available and the name is
113 * something other than "long long", #define Llong to be the name,
114 * and if "unsigned Llong" does not work as an unsigned version of
115 * Llong, #define #ULLong to be the corresponding unsigned type.
116 * #define KR_headers for old-style C function headers.
117 * #define Bad_float_h if your system lacks a float.h or if it does not
118 * define some or all of DBL_DIG, DBL_MAX_10_EXP, DBL_MAX_EXP,
119 * FLT_RADIX, FLT_ROUNDS, and DBL_MAX.
120 * #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n)
121 * if memory is available and otherwise does something you deem
122 * appropriate. If MALLOC is undefined, malloc will be invoked
123 * directly -- and assumed always to succeed. Similarly, if you
124 * want something other than the system's free() to be called to
125 * recycle memory acquired from MALLOC, #define FREE to be the
126 * name of the alternate routine. (FREE or free is only called in
127 * pathological cases, e.g., in a gdtoa call after a gdtoa return in
128 * mode 3 with thousands of digits requested.)
129 * #define Omit_Private_Memory to omit logic (added Jan. 1998) for making
130 * memory allocations from a private pool of memory when possible.
131 * When used, the private pool is PRIVATE_MEM bytes long: 2304 bytes,
132 * unless #defined to be a different length. This default length
133 * suffices to get rid of MALLOC calls except for unusual cases,
134 * such as decimal-to-binary conversion of a very long string of
135 * digits. When converting IEEE double precision values, the
136 * longest string gdtoa can return is about 751 bytes long. For
137 * conversions by strtod of strings of 800 digits and all gdtoa
138 * conversions of IEEE doubles in single-threaded executions with
139 * 8-byte pointers, PRIVATE_MEM >= 7400 appears to suffice; with
140 * 4-byte pointers, PRIVATE_MEM >= 7112 appears adequate.
141 * #define NO_INFNAN_CHECK if you do not wish to have INFNAN_CHECK
142 * #defined automatically on IEEE systems. On such systems,
143 * when INFNAN_CHECK is #defined, strtod checks
144 * for Infinity and NaN (case insensitively).
145 * When INFNAN_CHECK is #defined and No_Hex_NaN is not #defined,
146 * strtodg also accepts (case insensitively) strings of the form
147 * NaN(x), where x is a string of hexadecimal digits (optionally
148 * preceded by 0x or 0X) and spaces; if there is only one string
149 * of hexadecimal digits, it is taken for the fraction bits of the
150 * resulting NaN; if there are two or more strings of hexadecimal
151 * digits, each string is assigned to the next available sequence
152 * of 32-bit words of fractions bits (starting with the most
153 * significant), right-aligned in each sequence.
154 * Unless GDTOA_NON_PEDANTIC_NANCHECK is #defined, input "NaN(...)"
155 * is consumed even when ... has the wrong form (in which case the
156 * "(...)" is consumed but ignored).
157 * #define MULTIPLE_THREADS if the system offers preemptively scheduled
158 * multiple threads. In this case, you must provide (or suitably
159 * #define) two locks, acquired by ACQUIRE_DTOA_LOCK(n) and freed
160 * by FREE_DTOA_LOCK(n) for n = 0 or 1. (The second lock, accessed
161 * in pow5mult, ensures lazy evaluation of only one copy of high
162 * powers of 5; omitting this lock would introduce a small
163 * probability of wasting memory, but would otherwise be harmless.)
164 * You must also invoke freedtoa(s) to free the value s returned by
165 * dtoa. You may do so whether or not MULTIPLE_THREADS is #defined.
166 * #define IMPRECISE_INEXACT if you do not care about the setting of
167 * the STRTOG_Inexact bits in the special case of doing IEEE double
168 * precision conversions (which could also be done by the strtod in
170 * #define NO_HEX_FP to disable recognition of C9x's hexadecimal
171 * floating-point constants.
172 * #define -DNO_ERRNO to suppress setting errno (in strtod.c and
174 * #define NO_STRING_H to use private versions of memcpy.
175 * On some K&R systems, it may also be necessary to
176 * #define DECLARE_SIZE_T in this case.
177 * #define USE_LOCALE to use the current locale's decimal_point value.
180 #ifndef GDTOAIMP_H_INCLUDED
181 #define GDTOAIMP_H_INCLUDED
187 #ifdef Honor_FLT_ROUNDS
193 #define Bug(x) {fprintf(stderr, "%s\n", x); exit(1);}
199 #include "libc_private.h"
201 #include "namespace.h"
203 #include "un-namespace.h"
204 #include "xlocale_private.h"
213 extern Char
*MALLOC
ANSI((size_t));
215 #define MALLOC malloc
220 #define NO_LOCALE_CACHE
221 #define Honor_FLT_ROUNDS
222 #define Trust_FLT_ROUNDS
225 #undef Avoid_Underflow
238 #define DBL_MAX_10_EXP 308
239 #define DBL_MAX_EXP 1024
241 #define DBL_MAX 1.7976931348623157e+308
246 #define DBL_MAX_10_EXP 75
247 #define DBL_MAX_EXP 63
249 #define DBL_MAX 7.2370055773322621e+75
254 #define DBL_MAX_10_EXP 38
255 #define DBL_MAX_EXP 127
257 #define DBL_MAX 1.7014118346046923e+38
262 #define LONG_MAX 2147483647
265 #else /* ifndef Bad_float_h */
267 #endif /* Bad_float_h */
270 #define Scale_Bit 0x10
290 #if defined(IEEE_8087) + defined(IEEE_MC68k) + defined(VAX) + defined(IBM) != 1
291 Exactly one of IEEE_8087
, IEEE_MC68k
, VAX
, or IBM should be defined
.
294 typedef union { double d
; ULong L
[2]; } U
;
297 #define word0(x) (x)->L[1]
298 #define word1(x) (x)->L[0]
300 #define word0(x) (x)->L[0]
301 #define word1(x) (x)->L[1]
303 #define dval(x) (x)->d
305 /* The following definition of Storeinc is appropriate for MIPS processors.
306 * An alternative that might be better on some machines is
307 * #define Storeinc(a,b,c) (*a++ = b << 16 | c & 0xffff)
309 #if defined(IEEE_8087) + defined(VAX)
310 #define Storeinc(a,b,c) (((unsigned short *)a)[1] = (unsigned short)b, \
311 ((unsigned short *)a)[0] = (unsigned short)c, a++)
313 #define Storeinc(a,b,c) (((unsigned short *)a)[0] = (unsigned short)b, \
314 ((unsigned short *)a)[1] = (unsigned short)c, a++)
317 /* #define P DBL_MANT_DIG */
318 /* Ten_pmax = floor(P*log(2)/log(5)) */
319 /* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */
320 /* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */
321 /* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */
325 #define Exp_shift1 20
326 #define Exp_msk1 0x100000
327 #define Exp_msk11 0x100000
328 #define Exp_mask 0x7ff00000
332 #define Exp_1 0x3ff00000
333 #define Exp_11 0x3ff00000
335 #define Frac_mask 0xfffff
336 #define Frac_mask1 0xfffff
339 #define Bndry_mask 0xfffff
340 #define Bndry_mask1 0xfffff
342 #define Sign_bit 0x80000000
351 #define Flt_Rounds FLT_ROUNDS
355 #endif /*Flt_Rounds*/
357 #else /* ifndef IEEE_Arith */
358 #undef Sudden_Underflow
359 #define Sudden_Underflow
364 #define Exp_shift1 24
365 #define Exp_msk1 0x1000000
366 #define Exp_msk11 0x1000000
367 #define Exp_mask 0x7f000000
370 #define Exp_1 0x41000000
371 #define Exp_11 0x41000000
372 #define Ebits 8 /* exponent has 7 bits, but 8 is the right value in b2d */
373 #define Frac_mask 0xffffff
374 #define Frac_mask1 0xffffff
377 #define Bndry_mask 0xefffff
378 #define Bndry_mask1 0xffffff
380 #define Sign_bit 0x80000000
382 #define Tiny0 0x100000
391 #define Exp_msk1 0x80
392 #define Exp_msk11 0x800000
393 #define Exp_mask 0x7f80
396 #define Exp_1 0x40800000
397 #define Exp_11 0x4080
399 #define Frac_mask 0x7fffff
400 #define Frac_mask1 0xffff007f
403 #define Bndry_mask 0xffff007f
404 #define Bndry_mask1 0xffff007f
406 #define Sign_bit 0x8000
412 #endif /* IBM, VAX */
413 #endif /* IEEE_Arith */
418 #ifdef ROUND_BIASED_without_Round_Up
425 #define rounded_product(a,b) a = rnd_prod(a, b)
426 #define rounded_quotient(a,b) a = rnd_quot(a, b)
428 extern double rnd_prod(), rnd_quot();
430 extern double rnd_prod(double, double), rnd_quot(double, double);
433 #define rounded_product(a,b) a *= b
434 #define rounded_quotient(a,b) a /= b
437 #define Big0 (Frac_mask1 | Exp_msk1*(DBL_MAX_EXP+Bias-1))
438 #define Big1 0xffffffff
450 /* When Pack_32 is not defined, we store 16 bits per 32-bit Long.
451 * This makes some inner loops simpler and sometimes saves work
452 * during multiplications, but it often seems to make things slightly
453 * slower. Hence the default is now to store 32 bits per Long.
456 #else /* long long available */
458 #define Llong long long
461 #define ULLong unsigned Llong
463 #endif /* NO_LONG_LONG */
469 #define ALL_ON 0xffffffff
474 #define ALL_ON 0xffff
477 #define MULTIPLE_THREADS
478 extern pthread_mutex_t __gdtoa_locks
[2];
479 #define ACQUIRE_DTOA_LOCK(n) do { \
481 _pthread_mutex_lock(&__gdtoa_locks[n]); \
483 #define FREE_DTOA_LOCK(n) do { \
485 _pthread_mutex_unlock(&__gdtoa_locks[n]); \
493 int k
, maxwds
, sign
, wds
;
497 typedef struct Bigint Bigint
;
500 #ifdef DECLARE_SIZE_T
501 typedef unsigned int size_t;
503 extern void memcpy_D2A
ANSI((void*, const void*, size_t));
504 #define Bcopy(x,y) memcpy_D2A(&x->sign,&y->sign,y->wds*sizeof(ULong) + 2*sizeof(int))
505 #else /* !NO_STRING_H */
506 #define Bcopy(x,y) memcpy(&x->sign,&y->sign,y->wds*sizeof(ULong) + 2*sizeof(int))
507 #endif /* NO_STRING_H */
510 * Paranoia: Protect exported symbols, including ones in files we don't
511 * compile right now. The standard strtof and strtod survive.
514 #define gdtoa __gdtoa
515 #define freedtoa __freedtoa
516 #define strtodg __strtodg
517 #define g_ddfmt __g_ddfmt
518 #define g_dfmt __g_dfmt
519 #define g_ffmt __g_ffmt
520 #define g_Qfmt __g_Qfmt
521 #define g_xfmt __g_xfmt
522 #define g_xLfmt __g_xLfmt
523 #define strtoId __strtoId
524 #define strtoIdd __strtoIdd
525 #define strtoIf __strtoIf
526 #define strtoIQ __strtoIQ
527 #define strtoIx __strtoIx
528 #define strtoIxL __strtoIxL
529 #define strtord_l __strtord_l
530 #define strtordd __strtordd
531 #define strtorf __strtorf
532 #define strtorQ_l __strtorQ_l
533 #define strtorx_l __strtorx_l
534 #define strtorxL __strtorxL
535 #define strtodI __strtodI
536 #define strtopd __strtopd
537 #define strtopdd __strtopdd
538 #define strtopf __strtopf
539 #define strtopQ __strtopQ
540 #define strtopx __strtopx
541 #define strtopxL __strtopxL
543 /* Protect gdtoa-internal symbols */
544 #define Balloc __Balloc_D2A
545 #define Bfree __Bfree_D2A
546 #define ULtoQ __ULtoQ_D2A
547 #define ULtof __ULtof_D2A
548 #define ULtod __ULtod_D2A
549 #define ULtodd __ULtodd_D2A
550 #define ULtox __ULtox_D2A
551 #define ULtoxL __ULtoxL_D2A
552 #define any_on __any_on_D2A
553 #define b2d __b2d_D2A
554 #define bigtens __bigtens_D2A
555 #define cmp __cmp_D2A
556 #define copybits __copybits_D2A
557 #define d2b __d2b_D2A
558 #define decrement __decrement_D2A
559 #define diff __diff_D2A
560 #define dtoa_result __dtoa_result_D2A
561 #define g__fmt __g__fmt_D2A
562 #define gethex __gethex_D2A
563 #define hexdig __hexdig_D2A
564 #define hexdig_init_D2A __hexdig_init_D2A
565 #define hexnan __hexnan_D2A
566 #define hi0bits __hi0bits_D2A
567 #define hi0bits_D2A __hi0bits_D2A
568 #define i2b __i2b_D2A
569 #define increment __increment_D2A
570 #define lo0bits __lo0bits_D2A
571 #define lshift __lshift_D2A
572 #define match __match_D2A
573 #define mult __mult_D2A
574 #define multadd __multadd_D2A
575 #define nrv_alloc __nrv_alloc_D2A
576 #define pow5mult __pow5mult_D2A
577 #define quorem __quorem_D2A
578 #define ratio __ratio_D2A
579 #define rshift __rshift_D2A
580 #define rv_alloc __rv_alloc_D2A
581 #define s2b __s2b_D2A
582 #define set_ones __set_ones_D2A
583 #define strcp __strcp_D2A
584 #define strcp_D2A __strcp_D2A
585 #define strtoIg __strtoIg_D2A
586 #define sum __sum_D2A
587 #define tens __tens_D2A
588 #define tinytens __tinytens_D2A
589 #define tinytens __tinytens_D2A
590 #define trailz __trailz_D2A
591 #define ulp __ulp_D2A
593 extern char *dtoa_result
;
594 extern CONST
double bigtens
[], tens
[], tinytens
[];
595 extern unsigned char hexdig
[];
597 extern Bigint
*Balloc
ANSI((int));
598 extern void Bfree
ANSI((Bigint
*));
599 extern void ULtof
ANSI((ULong
*, ULong
*, Long
, int));
600 extern void ULtod
ANSI((ULong
*, ULong
*, Long
, int));
601 extern void ULtodd
ANSI((ULong
*, ULong
*, Long
, int));
602 extern void ULtoQ
ANSI((ULong
*, ULong
*, Long
, int));
603 extern void ULtox
ANSI((UShort
*, ULong
*, Long
, int));
604 extern void ULtoxL
ANSI((ULong
*, ULong
*, Long
, int));
605 extern ULong any_on
ANSI((Bigint
*, int));
606 extern double b2d
ANSI((Bigint
*, int*));
607 extern int cmp
ANSI((Bigint
*, Bigint
*));
608 extern void copybits
ANSI((ULong
*, int, Bigint
*));
609 extern Bigint
*d2b
ANSI((double, int*, int*));
610 extern void decrement
ANSI((Bigint
*));
611 extern Bigint
*diff
ANSI((Bigint
*, Bigint
*));
612 extern char *dtoa
ANSI((double d
, int mode
, int ndigits
,
613 int *decpt
, int *sign
, char **rve
));
614 extern void freedtoa
ANSI((char*));
615 extern char *gdtoa
ANSI((FPI
*fpi
, int be
, ULong
*bits
, int *kindp
,
616 int mode
, int ndigits
, int *decpt
, char **rve
));
617 extern char *g__fmt
ANSI((char*, char*, char*, int, ULong
, size_t));
618 extern int gethex
ANSI((CONST
char**, FPI
*, Long
*, Bigint
**, int));
619 extern void hexdig_init_D2A(Void
);
620 extern int hexnan
ANSI((CONST
char**, FPI
*, ULong
*));
621 extern int hi0bits
ANSI((ULong
));
622 extern Bigint
*i2b
ANSI((int));
623 extern Bigint
*increment
ANSI((Bigint
*));
624 extern int lo0bits
ANSI((ULong
*));
625 extern Bigint
*lshift
ANSI((Bigint
*, int));
626 extern int match
ANSI((CONST
char**, char*));
627 extern Bigint
*mult
ANSI((Bigint
*, Bigint
*));
628 extern Bigint
*multadd
ANSI((Bigint
*, int, int));
629 extern char *nrv_alloc
ANSI((char*, char **, int));
630 extern Bigint
*pow5mult
ANSI((Bigint
*, int));
631 extern int quorem
ANSI((Bigint
*, Bigint
*));
632 extern double ratio
ANSI((Bigint
*, Bigint
*));
633 extern void rshift
ANSI((Bigint
*, int));
634 extern char *rv_alloc
ANSI((int));
635 extern Bigint
*s2b
ANSI((CONST
char*, int, int, ULong
, int));
636 extern Bigint
*set_ones
ANSI((Bigint
*, int));
637 extern char *strcp
ANSI((char*, const char*));
638 extern int strtodg_l
ANSI((CONST
char*, char**, FPI
*, Long
*, ULong
*, locale_t
));
640 extern int strtoId
ANSI((CONST
char *, char **, double *, double *));
641 extern int strtoIdd
ANSI((CONST
char *, char **, double *, double *));
642 extern int strtoIf
ANSI((CONST
char *, char **, float *, float *));
643 extern int strtoIg
ANSI((CONST
char*, char**, FPI
*, Long
*, Bigint
**, int*));
644 extern int strtoIQ
ANSI((CONST
char *, char **, void *, void *));
645 extern int strtoIx
ANSI((CONST
char *, char **, void *, void *));
646 extern int strtoIxL
ANSI((CONST
char *, char **, void *, void *));
647 extern double strtod
ANSI((const char *s00
, char **se
));
648 extern double strtod_l
ANSI((const char *s00
, char **se
, locale_t
));
649 extern int strtopQ
ANSI((CONST
char *, char **, Void
*));
650 extern int strtopf
ANSI((CONST
char *, char **, float *));
651 extern int strtopd
ANSI((CONST
char *, char **, double *));
652 extern int strtopdd
ANSI((CONST
char *, char **, double *));
653 extern int strtopx
ANSI((CONST
char *, char **, Void
*));
654 extern int strtopxL
ANSI((CONST
char *, char **, Void
*));
655 extern int strtord_l
ANSI((CONST
char *, char **, int, double *, locale_t
));
656 extern int strtordd
ANSI((CONST
char *, char **, int, double *));
657 extern int strtorf
ANSI((CONST
char *, char **, int, float *));
658 extern int strtorQ_l
ANSI((CONST
char *, char **, int, void *, locale_t
));
659 extern int strtorx_l
ANSI((CONST
char *, char **, int, void *, locale_t
));
660 extern int strtorxL
ANSI((CONST
char *, char **, int, void *));
661 extern Bigint
*sum
ANSI((Bigint
*, Bigint
*));
662 extern int trailz
ANSI((Bigint
*));
663 extern double ulp
ANSI((U
*));
669 * NAN_WORD0 and NAN_WORD1 are only referenced in strtod.c. Prior to
670 * 20050115, they used to be hard-wired here (to 0x7ff80000 and 0,
671 * respectively), but now are determined by compiling and running
672 * qnan.c to generate gd_qnan.h, which specifies d_QNAN0 and d_QNAN1.
673 * Formerly gdtoaimp.h recommended supplying suitable -DNAN_WORD0=...
674 * and -DNAN_WORD1=... values if necessary. This should still work.
675 * (On HP Series 700/800 machines, -DNAN_WORD0=0x7ff40000 works.)
678 #ifndef NO_INFNAN_CHECK
686 #define NAN_WORD0 d_QNAN0
689 #define NAN_WORD1 d_QNAN1
695 #define NAN_WORD0 d_QNAN1
698 #define NAN_WORD1 d_QNAN0
706 #ifdef Sudden_Underflow
712 #endif /* GDTOAIMP_H_INCLUDED */