xref: /netbsd-src/external/gpl3/gcc/dist/gcc/real.h (revision b1e838363e3c6fc78a55519254d99869742dd33c)
1 /* Definitions of floating-point access for GNU compiler.
2    Copyright (C) 1989-2022 Free Software Foundation, Inc.
3 
4    This file is part of GCC.
5 
6    GCC is free software; you can redistribute it and/or modify it under
7    the terms of the GNU General Public License as published by the Free
8    Software Foundation; either version 3, or (at your option) any later
9    version.
10 
11    GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12    WARRANTY; without even the implied warranty of MERCHANTABILITY or
13    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14    for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with GCC; see the file COPYING3.  If not see
18    <http://www.gnu.org/licenses/>.  */
19 
20 #ifndef GCC_REAL_H
21 #define GCC_REAL_H
22 
23 /* An expanded form of the represented number.  */
24 
25 /* Enumerate the special cases of numbers that we encounter.  */
26 enum real_value_class {
27   rvc_zero,
28   rvc_normal,
29   rvc_inf,
30   rvc_nan
31 };
32 
33 #define SIGNIFICAND_BITS	(128 + HOST_BITS_PER_LONG)
34 #define EXP_BITS		(32 - 6)
35 #define MAX_EXP			((1 << (EXP_BITS - 1)) - 1)
36 #define SIGSZ			(SIGNIFICAND_BITS / HOST_BITS_PER_LONG)
37 #define SIG_MSB			((unsigned long)1 << (HOST_BITS_PER_LONG - 1))
38 
39 struct GTY(()) real_value {
40   /* Use the same underlying type for all bit-fields, so as to make
41      sure they're packed together, otherwise REAL_VALUE_TYPE_SIZE will
42      be miscomputed.  */
43   unsigned int /* ENUM_BITFIELD (real_value_class) */ cl : 2;
44   /* 1 if number is decimal floating point.  */
45   unsigned int decimal : 1;
46   /* 1 if number is negative.  */
47   unsigned int sign : 1;
48   /* 1 if number is signalling.  */
49   unsigned int signalling : 1;
50   /* 1 if number is canonical
51   All are generally used for handling cases in real.cc.  */
52   unsigned int canonical : 1;
53   /* unbiased exponent of the number.  */
54   unsigned int uexp : EXP_BITS;
55   /* significand of the number.  */
56   unsigned long sig[SIGSZ];
57 };
58 
59 #define REAL_EXP(REAL) \
60   ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \
61    - (1 << (EXP_BITS - 1)))
62 #define SET_REAL_EXP(REAL, EXP) \
63   ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1)))
64 
65 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
66    needs to be a macro.  We do need to continue to have a structure tag
67    so that other headers can forward declare it.  */
68 #define REAL_VALUE_TYPE struct real_value
69 
70 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
71    consecutive "w" slots.  Moreover, we've got to compute the number of "w"
72    slots at preprocessor time, which means we can't use sizeof.  Guess.  */
73 
74 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
75 #define REAL_WIDTH \
76   (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
77    + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
78 
79 /* Verify the guess.  */
80 extern char test_real_width
81   [sizeof (REAL_VALUE_TYPE) <= REAL_WIDTH * sizeof (HOST_WIDE_INT) ? 1 : -1];
82 
83 /* Calculate the format for CONST_DOUBLE.  We need as many slots as
84    are necessary to overlay a REAL_VALUE_TYPE on them.  This could be
85    as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
86 
87    A number of places assume that there are always at least two 'w'
88    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
89 
90 #if REAL_WIDTH == 1
91 # define CONST_DOUBLE_FORMAT	 "ww"
92 #else
93 # if REAL_WIDTH == 2
94 #  define CONST_DOUBLE_FORMAT	 "ww"
95 # else
96 #  if REAL_WIDTH == 3
97 #   define CONST_DOUBLE_FORMAT	 "www"
98 #  else
99 #   if REAL_WIDTH == 4
100 #    define CONST_DOUBLE_FORMAT	 "wwww"
101 #   else
102 #    if REAL_WIDTH == 5
103 #     define CONST_DOUBLE_FORMAT "wwwww"
104 #    else
105 #     if REAL_WIDTH == 6
106 #      define CONST_DOUBLE_FORMAT "wwwwww"
107 #     else
108        #error "REAL_WIDTH > 6 not supported"
109 #     endif
110 #    endif
111 #   endif
112 #  endif
113 # endif
114 #endif
115 
116 
117 /* Describes the properties of the specific target format in use.  */
118 struct real_format
119 {
120   /* Move to and from the target bytes.  */
121   void (*encode) (const struct real_format *, long *,
122 		  const REAL_VALUE_TYPE *);
123   void (*decode) (const struct real_format *, REAL_VALUE_TYPE *,
124 		  const long *);
125 
126   /* The radix of the exponent and digits of the significand.  */
127   int b;
128 
129   /* Size of the significand in digits of radix B.  */
130   int p;
131 
132   /* Size of the significant of a NaN, in digits of radix B.  */
133   int pnan;
134 
135   /* The minimum negative integer, x, such that b**(x-1) is normalized.  */
136   int emin;
137 
138   /* The maximum integer, x, such that b**(x-1) is representable.  */
139   int emax;
140 
141   /* The bit position of the sign bit, for determining whether a value
142      is positive/negative, or -1 for a complex encoding.  */
143   int signbit_ro;
144 
145   /* The bit position of the sign bit, for changing the sign of a number,
146      or -1 for a complex encoding.  */
147   int signbit_rw;
148 
149   /* If this is an IEEE interchange format, the number of bits in the
150      format; otherwise, if it is an IEEE extended format, one more
151      than the greatest number of bits in an interchange format it
152      extends; otherwise 0.  Formats need not follow the IEEE 754-2008
153      recommended practice regarding how signaling NaNs are identified,
154      and may vary in the choice of default NaN, but must follow other
155      IEEE practice regarding having NaNs, infinities and subnormal
156      values, and the relation of minimum and maximum exponents, and,
157      for interchange formats, the details of the encoding.  */
158   int ieee_bits;
159 
160   /* Default rounding mode for operations on this format.  */
161   bool round_towards_zero;
162   bool has_sign_dependent_rounding;
163 
164   /* Properties of the format.  */
165   bool has_nans;
166   bool has_inf;
167   bool has_denorm;
168   bool has_signed_zero;
169   bool qnan_msb_set;
170   bool canonical_nan_lsbs_set;
171   const char *name;
172 };
173 
174 
175 /* The target format used for each floating point mode.
176    Float modes are followed by decimal float modes, with entries for
177    float modes indexed by (MODE - first float mode), and entries for
178    decimal float modes indexed by (MODE - first decimal float mode) +
179    the number of float modes.  */
180 extern const struct real_format *
181   real_format_for_mode[NUM_MODE_FLOAT + NUM_MODE_DECIMAL_FLOAT];
182 
183 #define REAL_MODE_FORMAT(MODE)						\
184   (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE)			\
185 			? (((MODE) - MIN_MODE_DECIMAL_FLOAT)		\
186 			   + NUM_MODE_FLOAT)				\
187 			: GET_MODE_CLASS (MODE) == MODE_FLOAT		\
188 			? ((MODE) - MIN_MODE_FLOAT)			\
189 			: (gcc_unreachable (), 0)])
190 
191 #define FLOAT_MODE_FORMAT(MODE) \
192   (REAL_MODE_FORMAT (as_a <scalar_float_mode> (GET_MODE_INNER (MODE))))
193 
194 /* The following macro determines whether the floating point format is
195    composite, i.e. may contain non-consecutive mantissa bits, in which
196    case compile-time FP overflow may not model run-time overflow.  */
197 #define MODE_COMPOSITE_P(MODE) \
198   (FLOAT_MODE_P (MODE) \
199    && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p)
200 
201 /* Accessor macros for format properties.  */
202 #define MODE_HAS_NANS(MODE) \
203   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans)
204 #define MODE_HAS_INFINITIES(MODE) \
205   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf)
206 #define MODE_HAS_SIGNED_ZEROS(MODE) \
207   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero)
208 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \
209   (FLOAT_MODE_P (MODE) \
210    && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding)
211 
212 /* This class allows functions in this file to accept a floating-point
213    format as either a mode or an explicit real_format pointer.  In the
214    former case the mode must be VOIDmode (which means "no particular
215    format") or must satisfy SCALAR_FLOAT_MODE_P.  */
216 class format_helper
217 {
218 public:
format_helper(const real_format * format)219   format_helper (const real_format *format) : m_format (format) {}
220   template<typename T> format_helper (const T &);
221   const real_format *operator-> () const { return m_format; }
222   operator const real_format *() const { return m_format; }
223 
decimal_p()224   bool decimal_p () const { return m_format && m_format->b == 10; }
225   bool can_represent_integral_type_p (tree type) const;
226 
227 private:
228   const real_format *m_format;
229 };
230 
231 template<typename T>
format_helper(const T & m)232 inline format_helper::format_helper (const T &m)
233   : m_format (m == VOIDmode ? 0 : REAL_MODE_FORMAT (m))
234 {}
235 
236 /* Declare functions in real.cc.  */
237 
238 /* True if the given mode has a NaN representation and the treatment of
239    NaN operands is important.  Certain optimizations, such as folding
240    x * 0 into 0, are not correct for NaN operands, and are normally
241    disabled for modes with NaNs.  The user can ask for them to be
242    done anyway using the -funsafe-math-optimizations switch.  */
243 extern bool HONOR_NANS (machine_mode);
244 extern bool HONOR_NANS (const_tree);
245 extern bool HONOR_NANS (const_rtx);
246 
247 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
248 extern bool HONOR_SNANS (machine_mode);
249 extern bool HONOR_SNANS (const_tree);
250 extern bool HONOR_SNANS (const_rtx);
251 
252 /* As for HONOR_NANS, but true if the mode can represent infinity and
253    the treatment of infinite values is important.  */
254 extern bool HONOR_INFINITIES (machine_mode);
255 extern bool HONOR_INFINITIES (const_tree);
256 extern bool HONOR_INFINITIES (const_rtx);
257 
258 /* Like HONOR_NANS, but true if the given mode distinguishes between
259    positive and negative zero, and the sign of zero is important.  */
260 extern bool HONOR_SIGNED_ZEROS (machine_mode);
261 extern bool HONOR_SIGNED_ZEROS (const_tree);
262 extern bool HONOR_SIGNED_ZEROS (const_rtx);
263 
264 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
265    and the rounding mode is important.  */
266 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (machine_mode);
267 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_tree);
268 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_rtx);
269 
270 /* Binary or unary arithmetic on tree_code.  */
271 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *,
272 			     const REAL_VALUE_TYPE *);
273 
274 /* Compare reals by tree_code.  */
275 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
276 
277 /* Determine whether a floating-point value X is infinite.  */
278 extern bool real_isinf (const REAL_VALUE_TYPE *);
279 
280 /* Determine whether a floating-point value X is a NaN.  */
281 extern bool real_isnan (const REAL_VALUE_TYPE *);
282 
283 /* Determine whether a floating-point value X is a signaling NaN.  */
284 extern bool real_issignaling_nan (const REAL_VALUE_TYPE *);
285 
286 /* Determine whether a floating-point value X is finite.  */
287 extern bool real_isfinite (const REAL_VALUE_TYPE *);
288 
289 /* Determine whether a floating-point value X is negative.  */
290 extern bool real_isneg (const REAL_VALUE_TYPE *);
291 
292 /* Determine whether a floating-point value X is minus zero.  */
293 extern bool real_isnegzero (const REAL_VALUE_TYPE *);
294 
295 /* Test relationships between reals.  */
296 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
297 extern bool real_equal (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
298 extern bool real_less (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
299 
300 /* Extend or truncate to a new format.  */
301 extern void real_convert (REAL_VALUE_TYPE *, format_helper,
302 			  const REAL_VALUE_TYPE *);
303 
304 /* Return true if truncating to NEW is exact.  */
305 extern bool exact_real_truncate (format_helper, const REAL_VALUE_TYPE *);
306 
307 /* Render R as a decimal floating point constant.  */
308 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t,
309 			     size_t, int);
310 
311 /* Render R as a decimal floating point constant, rounded so as to be
312    parsed back to the same value when interpreted in mode MODE.  */
313 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t,
314 				      size_t, int, machine_mode);
315 
316 /* Render R as a hexadecimal floating point constant.  */
317 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *,
318 				 size_t, size_t, int);
319 
320 /* Render R as an integer.  */
321 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *);
322 
323 /* Initialize R from a decimal or hexadecimal string.  Return -1 if
324    the value underflows, +1 if overflows, and 0 otherwise.  */
325 extern int real_from_string (REAL_VALUE_TYPE *, const char *);
326 /* Wrapper to allow different internal representation for decimal floats. */
327 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, format_helper);
328 
329 extern long real_to_target (long *, const REAL_VALUE_TYPE *, format_helper);
330 
331 extern void real_from_target (REAL_VALUE_TYPE *, const long *,
332 			      format_helper);
333 
334 extern void real_inf (REAL_VALUE_TYPE *);
335 
336 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, format_helper);
337 
338 extern void real_maxval (REAL_VALUE_TYPE *, int, machine_mode);
339 
340 extern void real_2expN (REAL_VALUE_TYPE *, int, format_helper);
341 
342 extern unsigned int real_hash (const REAL_VALUE_TYPE *);
343 
344 
345 /* Target formats defined in real.cc.  */
346 extern const struct real_format ieee_single_format;
347 extern const struct real_format mips_single_format;
348 extern const struct real_format motorola_single_format;
349 extern const struct real_format spu_single_format;
350 extern const struct real_format ieee_double_format;
351 extern const struct real_format mips_double_format;
352 extern const struct real_format motorola_double_format;
353 extern const struct real_format ieee_extended_motorola_format;
354 extern const struct real_format ieee_extended_intel_96_format;
355 extern const struct real_format ieee_extended_intel_96_round_53_format;
356 extern const struct real_format ieee_extended_intel_128_format;
357 extern const struct real_format ibm_extended_format;
358 extern const struct real_format mips_extended_format;
359 extern const struct real_format ieee_quad_format;
360 extern const struct real_format mips_quad_format;
361 extern const struct real_format vax_f_format;
362 extern const struct real_format vax_d_format;
363 extern const struct real_format vax_g_format;
364 extern const struct real_format real_internal_format;
365 extern const struct real_format decimal_single_format;
366 extern const struct real_format decimal_double_format;
367 extern const struct real_format decimal_quad_format;
368 extern const struct real_format ieee_half_format;
369 extern const struct real_format arm_half_format;
370 extern const struct real_format arm_bfloat_half_format;
371 
372 
373 /* ====================================================================== */
374 /* Crap.  */
375 
376 /* Determine whether a floating-point value X is infinite.  */
377 #define REAL_VALUE_ISINF(x)		real_isinf (&(x))
378 
379 /* Determine whether a floating-point value X is a NaN.  */
380 #define REAL_VALUE_ISNAN(x)		real_isnan (&(x))
381 
382 /* Determine whether a floating-point value X is a signaling NaN.  */
383 #define REAL_VALUE_ISSIGNALING_NAN(x)  real_issignaling_nan (&(x))
384 
385 /* Determine whether a floating-point value X is negative.  */
386 #define REAL_VALUE_NEGATIVE(x)		real_isneg (&(x))
387 
388 /* Determine whether a floating-point value X is minus zero.  */
389 #define REAL_VALUE_MINUS_ZERO(x)	real_isnegzero (&(x))
390 
391 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
392 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)			\
393   real_to_target (OUT, &(IN),						\
394 		  float_mode_for_size (LONG_DOUBLE_TYPE_SIZE).require ())
395 
396 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
397   real_to_target (OUT, &(IN), float_mode_for_size (64).require ())
398 
399 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
400 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
401   ((OUT) = real_to_target (NULL, &(IN), float_mode_for_size (32).require ()))
402 
403 /* Real values to IEEE 754 decimal floats.  */
404 
405 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
406 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
407   real_to_target (OUT, &(IN), decimal_float_mode_for_size (128).require ())
408 
409 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
410   real_to_target (OUT, &(IN), decimal_float_mode_for_size (64).require ())
411 
412 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
413 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
414   ((OUT) = real_to_target (NULL, &(IN), \
415 			   decimal_float_mode_for_size (32).require ()))
416 
417 extern REAL_VALUE_TYPE real_value_truncate (format_helper, REAL_VALUE_TYPE);
418 
419 extern REAL_VALUE_TYPE real_value_negate (const REAL_VALUE_TYPE *);
420 extern REAL_VALUE_TYPE real_value_abs (const REAL_VALUE_TYPE *);
421 
422 extern int significand_size (format_helper);
423 
424 extern REAL_VALUE_TYPE real_from_string2 (const char *, format_helper);
425 
426 #define REAL_VALUE_ATOF(s, m) \
427   real_from_string2 (s, m)
428 
429 #define CONST_DOUBLE_ATOF(s, m) \
430   const_double_from_real_value (real_from_string2 (s, m), m)
431 
432 #define REAL_VALUE_FIX(r) \
433   real_to_integer (&(r))
434 
435 /* ??? Not quite right.  */
436 #define REAL_VALUE_UNSIGNED_FIX(r) \
437   real_to_integer (&(r))
438 
439 /* ??? These were added for Paranoia support.  */
440 
441 /* Return floor log2(R).  */
442 extern int real_exponent (const REAL_VALUE_TYPE *);
443 
444 /* R = A * 2**EXP.  */
445 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int);
446 
447 /* **** End of software floating point emulator interface macros **** */
448 
449 /* Constant real values 0, 1, 2, -1 and 0.5.  */
450 
451 extern REAL_VALUE_TYPE dconst0;
452 extern REAL_VALUE_TYPE dconst1;
453 extern REAL_VALUE_TYPE dconst2;
454 extern REAL_VALUE_TYPE dconstm1;
455 extern REAL_VALUE_TYPE dconsthalf;
456 
457 #define dconst_e() (*dconst_e_ptr ())
458 #define dconst_third() (*dconst_third_ptr ())
459 #define dconst_quarter() (*dconst_quarter_ptr ())
460 #define dconst_sixth() (*dconst_sixth_ptr ())
461 #define dconst_ninth() (*dconst_ninth_ptr ())
462 #define dconst_sqrt2() (*dconst_sqrt2_ptr ())
463 
464 /* Function to return the real value special constant 'e'.  */
465 extern const REAL_VALUE_TYPE * dconst_e_ptr (void);
466 
467 /* Returns a cached REAL_VALUE_TYPE corresponding to 1/n, for various n.  */
468 extern const REAL_VALUE_TYPE *dconst_third_ptr (void);
469 extern const REAL_VALUE_TYPE *dconst_quarter_ptr (void);
470 extern const REAL_VALUE_TYPE *dconst_sixth_ptr (void);
471 extern const REAL_VALUE_TYPE *dconst_ninth_ptr (void);
472 
473 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2).  */
474 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void);
475 
476 /* Function to return a real value (not a tree node)
477    from a given integer constant.  */
478 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree);
479 
480 /* Return a CONST_DOUBLE with value R and mode M.  */
481 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, machine_mode);
482 
483 /* Replace R by 1/R in the given format, if the result is exact.  */
484 extern bool exact_real_inverse (format_helper, REAL_VALUE_TYPE *);
485 
486 /* Return true if arithmetic on values in IMODE that were promoted
487    from values in TMODE is equivalent to direct arithmetic on values
488    in TMODE.  */
489 bool real_can_shorten_arithmetic (machine_mode, machine_mode);
490 
491 /* In tree.cc: wrap up a REAL_VALUE_TYPE in a tree node.  */
492 extern tree build_real (tree, REAL_VALUE_TYPE);
493 
494 /* Likewise, but first truncate the value to the type.  */
495 extern tree build_real_truncate (tree, REAL_VALUE_TYPE);
496 
497 /* Calculate R as X raised to the integer exponent N in format FMT.  */
498 extern bool real_powi (REAL_VALUE_TYPE *, format_helper,
499 		       const REAL_VALUE_TYPE *, HOST_WIDE_INT);
500 
501 /* Standard round to integer value functions.  */
502 extern void real_trunc (REAL_VALUE_TYPE *, format_helper,
503 			const REAL_VALUE_TYPE *);
504 extern void real_floor (REAL_VALUE_TYPE *, format_helper,
505 			const REAL_VALUE_TYPE *);
506 extern void real_ceil (REAL_VALUE_TYPE *, format_helper,
507 		       const REAL_VALUE_TYPE *);
508 extern void real_round (REAL_VALUE_TYPE *, format_helper,
509 			const REAL_VALUE_TYPE *);
510 extern void real_roundeven (REAL_VALUE_TYPE *, format_helper,
511 			    const REAL_VALUE_TYPE *);
512 
513 /* Set the sign of R to the sign of X.  */
514 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
515 
516 /* Check whether the real constant value given is an integer.  */
517 extern bool real_isinteger (const REAL_VALUE_TYPE *, format_helper);
518 extern bool real_isinteger (const REAL_VALUE_TYPE *, HOST_WIDE_INT *);
519 
520 /* Calculate nextafter (X, Y) in format FMT.  */
521 extern bool real_nextafter (REAL_VALUE_TYPE *, format_helper,
522 			    const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
523 
524 /* Write into BUF the maximum representable finite floating-point
525    number, (1 - b**-p) * b**emax for a given FP format FMT as a hex
526    float string.  BUF must be large enough to contain the result.  */
527 extern void get_max_float (const struct real_format *, char *, size_t, bool);
528 
529 #ifndef GENERATOR_FILE
530 /* real related routines.  */
531 extern wide_int real_to_integer (const REAL_VALUE_TYPE *, bool *, int);
532 extern void real_from_integer (REAL_VALUE_TYPE *, format_helper,
533 			       const wide_int_ref &, signop);
534 #endif
535 
536 /* Fills r with the largest value such that 1 + r*r won't overflow.
537    This is used in both sin (atan (x)) and cos (atan(x)) optimizations. */
538 extern void build_sinatan_real (REAL_VALUE_TYPE *, tree);
539 
540 #endif /* ! GCC_REAL_H */
541