1 /* Definitions of floating-point access for GNU compiler.
2    Copyright (C) 1989-2019 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   unsigned int decimal : 1;
45   unsigned int sign : 1;
46   unsigned int signalling : 1;
47   unsigned int canonical : 1;
48   unsigned int uexp : EXP_BITS;
49   unsigned long sig[SIGSZ];
50 };
51 
52 #define REAL_EXP(REAL) \
53   ((int)((REAL)->uexp ^ (unsigned int)(1 << (EXP_BITS - 1))) \
54    - (1 << (EXP_BITS - 1)))
55 #define SET_REAL_EXP(REAL, EXP) \
56   ((REAL)->uexp = ((unsigned int)(EXP) & (unsigned int)((1 << EXP_BITS) - 1)))
57 
58 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
59    needs to be a macro.  We do need to continue to have a structure tag
60    so that other headers can forward declare it.  */
61 #define REAL_VALUE_TYPE struct real_value
62 
63 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
64    consecutive "w" slots.  Moreover, we've got to compute the number of "w"
65    slots at preprocessor time, which means we can't use sizeof.  Guess.  */
66 
67 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
68 #define REAL_WIDTH \
69   (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
70    + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
71 
72 /* Verify the guess.  */
73 extern char test_real_width
74   [sizeof (REAL_VALUE_TYPE) <= REAL_WIDTH * sizeof (HOST_WIDE_INT) ? 1 : -1];
75 
76 /* Calculate the format for CONST_DOUBLE.  We need as many slots as
77    are necessary to overlay a REAL_VALUE_TYPE on them.  This could be
78    as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
79 
80    A number of places assume that there are always at least two 'w'
81    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
82 
83 #if REAL_WIDTH == 1
84 # define CONST_DOUBLE_FORMAT	 "ww"
85 #else
86 # if REAL_WIDTH == 2
87 #  define CONST_DOUBLE_FORMAT	 "ww"
88 # else
89 #  if REAL_WIDTH == 3
90 #   define CONST_DOUBLE_FORMAT	 "www"
91 #  else
92 #   if REAL_WIDTH == 4
93 #    define CONST_DOUBLE_FORMAT	 "wwww"
94 #   else
95 #    if REAL_WIDTH == 5
96 #     define CONST_DOUBLE_FORMAT "wwwww"
97 #    else
98 #     if REAL_WIDTH == 6
99 #      define CONST_DOUBLE_FORMAT "wwwwww"
100 #     else
101        #error "REAL_WIDTH > 6 not supported"
102 #     endif
103 #    endif
104 #   endif
105 #  endif
106 # endif
107 #endif
108 
109 
110 /* Describes the properties of the specific target format in use.  */
111 struct real_format
112 {
113   /* Move to and from the target bytes.  */
114   void (*encode) (const struct real_format *, long *,
115 		  const REAL_VALUE_TYPE *);
116   void (*decode) (const struct real_format *, REAL_VALUE_TYPE *,
117 		  const long *);
118 
119   /* The radix of the exponent and digits of the significand.  */
120   int b;
121 
122   /* Size of the significand in digits of radix B.  */
123   int p;
124 
125   /* Size of the significant of a NaN, in digits of radix B.  */
126   int pnan;
127 
128   /* The minimum negative integer, x, such that b**(x-1) is normalized.  */
129   int emin;
130 
131   /* The maximum integer, x, such that b**(x-1) is representable.  */
132   int emax;
133 
134   /* The bit position of the sign bit, for determining whether a value
135      is positive/negative, or -1 for a complex encoding.  */
136   int signbit_ro;
137 
138   /* The bit position of the sign bit, for changing the sign of a number,
139      or -1 for a complex encoding.  */
140   int signbit_rw;
141 
142   /* If this is an IEEE interchange format, the number of bits in the
143      format; otherwise, if it is an IEEE extended format, one more
144      than the greatest number of bits in an interchange format it
145      extends; otherwise 0.  Formats need not follow the IEEE 754-2008
146      recommended practice regarding how signaling NaNs are identified,
147      and may vary in the choice of default NaN, but must follow other
148      IEEE practice regarding having NaNs, infinities and subnormal
149      values, and the relation of minimum and maximum exponents, and,
150      for interchange formats, the details of the encoding.  */
151   int ieee_bits;
152 
153   /* Default rounding mode for operations on this format.  */
154   bool round_towards_zero;
155   bool has_sign_dependent_rounding;
156 
157   /* Properties of the format.  */
158   bool has_nans;
159   bool has_inf;
160   bool has_denorm;
161   bool has_signed_zero;
162   bool qnan_msb_set;
163   bool canonical_nan_lsbs_set;
164   const char *name;
165 };
166 
167 
168 /* The target format used for each floating point mode.
169    Float modes are followed by decimal float modes, with entries for
170    float modes indexed by (MODE - first float mode), and entries for
171    decimal float modes indexed by (MODE - first decimal float mode) +
172    the number of float modes.  */
173 extern const struct real_format *
174   real_format_for_mode[MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1
175 		       + MAX_MODE_DECIMAL_FLOAT - MIN_MODE_DECIMAL_FLOAT + 1];
176 
177 #define REAL_MODE_FORMAT(MODE)						\
178   (real_format_for_mode[DECIMAL_FLOAT_MODE_P (MODE)			\
179 			? (((MODE) - MIN_MODE_DECIMAL_FLOAT)		\
180 			   + (MAX_MODE_FLOAT - MIN_MODE_FLOAT + 1))	\
181 			: GET_MODE_CLASS (MODE) == MODE_FLOAT		\
182 			? ((MODE) - MIN_MODE_FLOAT)			\
183 			: (gcc_unreachable (), 0)])
184 
185 #define FLOAT_MODE_FORMAT(MODE) \
186   (REAL_MODE_FORMAT (as_a <scalar_float_mode> (GET_MODE_INNER (MODE))))
187 
188 /* The following macro determines whether the floating point format is
189    composite, i.e. may contain non-consecutive mantissa bits, in which
190    case compile-time FP overflow may not model run-time overflow.  */
191 #define MODE_COMPOSITE_P(MODE) \
192   (FLOAT_MODE_P (MODE) \
193    && FLOAT_MODE_FORMAT (MODE)->pnan < FLOAT_MODE_FORMAT (MODE)->p)
194 
195 /* Accessor macros for format properties.  */
196 #define MODE_HAS_NANS(MODE) \
197   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_nans)
198 #define MODE_HAS_INFINITIES(MODE) \
199   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_inf)
200 #define MODE_HAS_SIGNED_ZEROS(MODE) \
201   (FLOAT_MODE_P (MODE) && FLOAT_MODE_FORMAT (MODE)->has_signed_zero)
202 #define MODE_HAS_SIGN_DEPENDENT_ROUNDING(MODE) \
203   (FLOAT_MODE_P (MODE) \
204    && FLOAT_MODE_FORMAT (MODE)->has_sign_dependent_rounding)
205 
206 /* This class allows functions in this file to accept a floating-point
207    format as either a mode or an explicit real_format pointer.  In the
208    former case the mode must be VOIDmode (which means "no particular
209    format") or must satisfy SCALAR_FLOAT_MODE_P.  */
210 class format_helper
211 {
212 public:
format_helper(const real_format * format)213   format_helper (const real_format *format) : m_format (format) {}
214   template<typename T> format_helper (const T &);
215   const real_format *operator-> () const { return m_format; }
216   operator const real_format *() const { return m_format; }
217 
decimal_p()218   bool decimal_p () const { return m_format && m_format->b == 10; }
219   bool can_represent_integral_type_p (tree type) const;
220 
221 private:
222   const real_format *m_format;
223 };
224 
225 template<typename T>
format_helper(const T & m)226 inline format_helper::format_helper (const T &m)
227   : m_format (m == VOIDmode ? 0 : REAL_MODE_FORMAT (m))
228 {}
229 
230 /* Declare functions in real.c.  */
231 
232 /* True if the given mode has a NaN representation and the treatment of
233    NaN operands is important.  Certain optimizations, such as folding
234    x * 0 into 0, are not correct for NaN operands, and are normally
235    disabled for modes with NaNs.  The user can ask for them to be
236    done anyway using the -funsafe-math-optimizations switch.  */
237 extern bool HONOR_NANS (machine_mode);
238 extern bool HONOR_NANS (const_tree);
239 extern bool HONOR_NANS (const_rtx);
240 
241 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
242 extern bool HONOR_SNANS (machine_mode);
243 extern bool HONOR_SNANS (const_tree);
244 extern bool HONOR_SNANS (const_rtx);
245 
246 /* As for HONOR_NANS, but true if the mode can represent infinity and
247    the treatment of infinite values is important.  */
248 extern bool HONOR_INFINITIES (machine_mode);
249 extern bool HONOR_INFINITIES (const_tree);
250 extern bool HONOR_INFINITIES (const_rtx);
251 
252 /* Like HONOR_NANS, but true if the given mode distinguishes between
253    positive and negative zero, and the sign of zero is important.  */
254 extern bool HONOR_SIGNED_ZEROS (machine_mode);
255 extern bool HONOR_SIGNED_ZEROS (const_tree);
256 extern bool HONOR_SIGNED_ZEROS (const_rtx);
257 
258 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
259    and the rounding mode is important.  */
260 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (machine_mode);
261 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_tree);
262 extern bool HONOR_SIGN_DEPENDENT_ROUNDING (const_rtx);
263 
264 /* Binary or unary arithmetic on tree_code.  */
265 extern bool real_arithmetic (REAL_VALUE_TYPE *, int, const REAL_VALUE_TYPE *,
266 			     const REAL_VALUE_TYPE *);
267 
268 /* Compare reals by tree_code.  */
269 extern bool real_compare (int, const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
270 
271 /* Determine whether a floating-point value X is infinite.  */
272 extern bool real_isinf (const REAL_VALUE_TYPE *);
273 
274 /* Determine whether a floating-point value X is a NaN.  */
275 extern bool real_isnan (const REAL_VALUE_TYPE *);
276 
277 /* Determine whether a floating-point value X is a signaling NaN.  */
278 extern bool real_issignaling_nan (const REAL_VALUE_TYPE *);
279 
280 /* Determine whether a floating-point value X is finite.  */
281 extern bool real_isfinite (const REAL_VALUE_TYPE *);
282 
283 /* Determine whether a floating-point value X is negative.  */
284 extern bool real_isneg (const REAL_VALUE_TYPE *);
285 
286 /* Determine whether a floating-point value X is minus zero.  */
287 extern bool real_isnegzero (const REAL_VALUE_TYPE *);
288 
289 /* Test relationships between reals.  */
290 extern bool real_identical (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
291 extern bool real_equal (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
292 extern bool real_less (const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
293 
294 /* Extend or truncate to a new format.  */
295 extern void real_convert (REAL_VALUE_TYPE *, format_helper,
296 			  const REAL_VALUE_TYPE *);
297 
298 /* Return true if truncating to NEW is exact.  */
299 extern bool exact_real_truncate (format_helper, const REAL_VALUE_TYPE *);
300 
301 /* Render R as a decimal floating point constant.  */
302 extern void real_to_decimal (char *, const REAL_VALUE_TYPE *, size_t,
303 			     size_t, int);
304 
305 /* Render R as a decimal floating point constant, rounded so as to be
306    parsed back to the same value when interpreted in mode MODE.  */
307 extern void real_to_decimal_for_mode (char *, const REAL_VALUE_TYPE *, size_t,
308 				      size_t, int, machine_mode);
309 
310 /* Render R as a hexadecimal floating point constant.  */
311 extern void real_to_hexadecimal (char *, const REAL_VALUE_TYPE *,
312 				 size_t, size_t, int);
313 
314 /* Render R as an integer.  */
315 extern HOST_WIDE_INT real_to_integer (const REAL_VALUE_TYPE *);
316 
317 /* Initialize R from a decimal or hexadecimal string.  Return -1 if
318    the value underflows, +1 if overflows, and 0 otherwise.  */
319 extern int real_from_string (REAL_VALUE_TYPE *, const char *);
320 /* Wrapper to allow different internal representation for decimal floats. */
321 extern void real_from_string3 (REAL_VALUE_TYPE *, const char *, format_helper);
322 
323 extern long real_to_target (long *, const REAL_VALUE_TYPE *, format_helper);
324 
325 extern void real_from_target (REAL_VALUE_TYPE *, const long *,
326 			      format_helper);
327 
328 extern void real_inf (REAL_VALUE_TYPE *);
329 
330 extern bool real_nan (REAL_VALUE_TYPE *, const char *, int, format_helper);
331 
332 extern void real_maxval (REAL_VALUE_TYPE *, int, machine_mode);
333 
334 extern void real_2expN (REAL_VALUE_TYPE *, int, format_helper);
335 
336 extern unsigned int real_hash (const REAL_VALUE_TYPE *);
337 
338 
339 /* Target formats defined in real.c.  */
340 extern const struct real_format ieee_single_format;
341 extern const struct real_format mips_single_format;
342 extern const struct real_format motorola_single_format;
343 extern const struct real_format spu_single_format;
344 extern const struct real_format ieee_double_format;
345 extern const struct real_format mips_double_format;
346 extern const struct real_format motorola_double_format;
347 extern const struct real_format ieee_extended_motorola_format;
348 extern const struct real_format ieee_extended_intel_96_format;
349 extern const struct real_format ieee_extended_intel_96_round_53_format;
350 extern const struct real_format ieee_extended_intel_128_format;
351 extern const struct real_format ibm_extended_format;
352 extern const struct real_format mips_extended_format;
353 extern const struct real_format ieee_quad_format;
354 extern const struct real_format mips_quad_format;
355 extern const struct real_format vax_f_format;
356 extern const struct real_format vax_d_format;
357 extern const struct real_format vax_g_format;
358 extern const struct real_format real_internal_format;
359 extern const struct real_format decimal_single_format;
360 extern const struct real_format decimal_double_format;
361 extern const struct real_format decimal_quad_format;
362 extern const struct real_format ieee_half_format;
363 extern const struct real_format arm_half_format;
364 
365 
366 /* ====================================================================== */
367 /* Crap.  */
368 
369 /* Determine whether a floating-point value X is infinite.  */
370 #define REAL_VALUE_ISINF(x)		real_isinf (&(x))
371 
372 /* Determine whether a floating-point value X is a NaN.  */
373 #define REAL_VALUE_ISNAN(x)		real_isnan (&(x))
374 
375 /* Determine whether a floating-point value X is a signaling NaN.  */
376 #define REAL_VALUE_ISSIGNALING_NAN(x)  real_issignaling_nan (&(x))
377 
378 /* Determine whether a floating-point value X is negative.  */
379 #define REAL_VALUE_NEGATIVE(x)		real_isneg (&(x))
380 
381 /* Determine whether a floating-point value X is minus zero.  */
382 #define REAL_VALUE_MINUS_ZERO(x)	real_isnegzero (&(x))
383 
384 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
385 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT)			\
386   real_to_target (OUT, &(IN),						\
387 		  float_mode_for_size (LONG_DOUBLE_TYPE_SIZE).require ())
388 
389 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
390   real_to_target (OUT, &(IN), float_mode_for_size (64).require ())
391 
392 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
393 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
394   ((OUT) = real_to_target (NULL, &(IN), float_mode_for_size (32).require ()))
395 
396 /* Real values to IEEE 754 decimal floats.  */
397 
398 /* IN is a REAL_VALUE_TYPE.  OUT is an array of longs.  */
399 #define REAL_VALUE_TO_TARGET_DECIMAL128(IN, OUT) \
400   real_to_target (OUT, &(IN), decimal_float_mode_for_size (128).require ())
401 
402 #define REAL_VALUE_TO_TARGET_DECIMAL64(IN, OUT) \
403   real_to_target (OUT, &(IN), decimal_float_mode_for_size (64).require ())
404 
405 /* IN is a REAL_VALUE_TYPE.  OUT is a long.  */
406 #define REAL_VALUE_TO_TARGET_DECIMAL32(IN, OUT) \
407   ((OUT) = real_to_target (NULL, &(IN), \
408 			   decimal_float_mode_for_size (32).require ()))
409 
410 extern REAL_VALUE_TYPE real_value_truncate (format_helper, REAL_VALUE_TYPE);
411 
412 extern REAL_VALUE_TYPE real_value_negate (const REAL_VALUE_TYPE *);
413 extern REAL_VALUE_TYPE real_value_abs (const REAL_VALUE_TYPE *);
414 
415 extern int significand_size (format_helper);
416 
417 extern REAL_VALUE_TYPE real_from_string2 (const char *, format_helper);
418 
419 #define REAL_VALUE_ATOF(s, m) \
420   real_from_string2 (s, m)
421 
422 #define CONST_DOUBLE_ATOF(s, m) \
423   const_double_from_real_value (real_from_string2 (s, m), m)
424 
425 #define REAL_VALUE_FIX(r) \
426   real_to_integer (&(r))
427 
428 /* ??? Not quite right.  */
429 #define REAL_VALUE_UNSIGNED_FIX(r) \
430   real_to_integer (&(r))
431 
432 /* ??? These were added for Paranoia support.  */
433 
434 /* Return floor log2(R).  */
435 extern int real_exponent (const REAL_VALUE_TYPE *);
436 
437 /* R = A * 2**EXP.  */
438 extern void real_ldexp (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *, int);
439 
440 /* **** End of software floating point emulator interface macros **** */
441 
442 /* Constant real values 0, 1, 2, -1 and 0.5.  */
443 
444 extern REAL_VALUE_TYPE dconst0;
445 extern REAL_VALUE_TYPE dconst1;
446 extern REAL_VALUE_TYPE dconst2;
447 extern REAL_VALUE_TYPE dconstm1;
448 extern REAL_VALUE_TYPE dconsthalf;
449 
450 #define dconst_e() (*dconst_e_ptr ())
451 #define dconst_third() (*dconst_third_ptr ())
452 #define dconst_quarter() (*dconst_quarter_ptr ())
453 #define dconst_sixth() (*dconst_sixth_ptr ())
454 #define dconst_ninth() (*dconst_ninth_ptr ())
455 #define dconst_sqrt2() (*dconst_sqrt2_ptr ())
456 
457 /* Function to return the real value special constant 'e'.  */
458 extern const REAL_VALUE_TYPE * dconst_e_ptr (void);
459 
460 /* Returns a cached REAL_VALUE_TYPE corresponding to 1/n, for various n.  */
461 extern const REAL_VALUE_TYPE *dconst_third_ptr (void);
462 extern const REAL_VALUE_TYPE *dconst_quarter_ptr (void);
463 extern const REAL_VALUE_TYPE *dconst_sixth_ptr (void);
464 extern const REAL_VALUE_TYPE *dconst_ninth_ptr (void);
465 
466 /* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2).  */
467 extern const REAL_VALUE_TYPE * dconst_sqrt2_ptr (void);
468 
469 /* Function to return a real value (not a tree node)
470    from a given integer constant.  */
471 REAL_VALUE_TYPE real_value_from_int_cst (const_tree, const_tree);
472 
473 /* Return a CONST_DOUBLE with value R and mode M.  */
474 extern rtx const_double_from_real_value (REAL_VALUE_TYPE, machine_mode);
475 
476 /* Replace R by 1/R in the given format, if the result is exact.  */
477 extern bool exact_real_inverse (format_helper, REAL_VALUE_TYPE *);
478 
479 /* Return true if arithmetic on values in IMODE that were promoted
480    from values in TMODE is equivalent to direct arithmetic on values
481    in TMODE.  */
482 bool real_can_shorten_arithmetic (machine_mode, machine_mode);
483 
484 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node.  */
485 extern tree build_real (tree, REAL_VALUE_TYPE);
486 
487 /* Likewise, but first truncate the value to the type.  */
488 extern tree build_real_truncate (tree, REAL_VALUE_TYPE);
489 
490 /* Calculate R as X raised to the integer exponent N in format FMT.  */
491 extern bool real_powi (REAL_VALUE_TYPE *, format_helper,
492 		       const REAL_VALUE_TYPE *, HOST_WIDE_INT);
493 
494 /* Standard round to integer value functions.  */
495 extern void real_trunc (REAL_VALUE_TYPE *, format_helper,
496 			const REAL_VALUE_TYPE *);
497 extern void real_floor (REAL_VALUE_TYPE *, format_helper,
498 			const REAL_VALUE_TYPE *);
499 extern void real_ceil (REAL_VALUE_TYPE *, format_helper,
500 		       const REAL_VALUE_TYPE *);
501 extern void real_round (REAL_VALUE_TYPE *, format_helper,
502 			const REAL_VALUE_TYPE *);
503 
504 /* Set the sign of R to the sign of X.  */
505 extern void real_copysign (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
506 
507 /* Check whether the real constant value given is an integer.  */
508 extern bool real_isinteger (const REAL_VALUE_TYPE *, format_helper);
509 extern bool real_isinteger (const REAL_VALUE_TYPE *, HOST_WIDE_INT *);
510 
511 /* Calculate nextafter (X, Y) in format FMT.  */
512 extern bool real_nextafter (REAL_VALUE_TYPE *, format_helper,
513 			    const REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
514 
515 /* Write into BUF the maximum representable finite floating-point
516    number, (1 - b**-p) * b**emax for a given FP format FMT as a hex
517    float string.  BUF must be large enough to contain the result.  */
518 extern void get_max_float (const struct real_format *, char *, size_t);
519 
520 #ifndef GENERATOR_FILE
521 /* real related routines.  */
522 extern wide_int real_to_integer (const REAL_VALUE_TYPE *, bool *, int);
523 extern void real_from_integer (REAL_VALUE_TYPE *, format_helper,
524 			       const wide_int_ref &, signop);
525 #endif
526 
527 /* Fills r with the largest value such that 1 + r*r won't overflow.
528    This is used in both sin (atan (x)) and cos (atan(x)) optimizations. */
529 extern void build_sinatan_real (REAL_VALUE_TYPE *, tree);
530 
531 #endif /* ! GCC_REAL_H */
532