1 /* Definitions of floating-point access for GNU compiler.
2 Copyright (C) 1989, 1991, 1994, 1996, 1997, 1998,
3 1999, 2000, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
27 /* An expanded form of the represented number. */
29 /* Enumerate the special cases of numbers that we encounter. */
30 enum real_value_class {
37 #define SIGNIFICAND_BITS (128 + HOST_BITS_PER_LONG)
38 #define EXP_BITS (32 - 3)
39 #define MAX_EXP ((1 << (EXP_BITS - 1)) - 1)
40 #define SIGSZ (SIGNIFICAND_BITS / HOST_BITS_PER_LONG)
41 #define SIG_MSB ((unsigned long)1 << (HOST_BITS_PER_LONG - 1))
43 struct real_value GTY(())
45 ENUM_BITFIELD (real_value_class) class : 2;
46 unsigned int sign : 1;
47 signed int exp : EXP_BITS;
48 unsigned long sig[SIGSZ];
51 /* Various headers condition prototypes on #ifdef REAL_VALUE_TYPE, so it
52 needs to be a macro. We do need to continue to have a structure tag
53 so that other headers can forward declare it. */
54 #define REAL_VALUE_TYPE struct real_value
56 /* We store a REAL_VALUE_TYPE into an rtx, and we do this by putting it in
57 consecutive "w" slots. Moreover, we've got to compute the number of "w"
58 slots at preprocessor time, which means we can't use sizeof. Guess. */
60 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32)
62 (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \
63 + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */
65 /* Verify the guess. */
66 extern char test_real_width
67 [sizeof(REAL_VALUE_TYPE) <= REAL_WIDTH*sizeof(HOST_WIDE_INT) ? 1 : -1];
69 /* Calculate the format for CONST_DOUBLE. We need as many slots as
70 are necessary to overlay a REAL_VALUE_TYPE on them. This could be
71 as many as four (32-bit HOST_WIDE_INT, 128-bit REAL_VALUE_TYPE).
73 A number of places assume that there are always at least two 'w'
74 slots in a CONST_DOUBLE, so we provide them even if one would suffice. */
77 # define CONST_DOUBLE_FORMAT "ww"
80 # define CONST_DOUBLE_FORMAT "ww"
83 # define CONST_DOUBLE_FORMAT "www"
86 # define CONST_DOUBLE_FORMAT "wwww"
89 # define CONST_DOUBLE_FORMAT "wwwww"
92 # define CONST_DOUBLE_FORMAT "wwwwww"
94 #error "REAL_WIDTH > 6 not supported"
103 /* Describes the properties of the specific target format in use. */
106 /* Move to and from the target bytes. */
107 void (*encode) PARAMS ((const struct real_format *, long *,
108 const REAL_VALUE_TYPE *));
109 void (*decode) PARAMS ((const struct real_format *, REAL_VALUE_TYPE *,
112 /* The radix of the exponent and digits of the significand. */
118 /* Size of the significand in digits of radix B. */
121 /* The minimum negative integer, x, such that b**(x-1) is normalized. */
124 /* The maximum integer, x, such that b**(x-1) is representable. */
127 /* Properties of the format. */
131 bool has_signed_zero;
136 /* The target format used for each floating floating point mode.
137 Indexed by MODE - QFmode. */
138 extern const struct real_format *real_format_for_mode[TFmode - QFmode + 1];
141 /* Declare functions in real.c. */
143 /* Binary or unary arithmetic on tree_code. */
144 extern void real_arithmetic PARAMS ((REAL_VALUE_TYPE *, int,
145 const REAL_VALUE_TYPE *,
146 const REAL_VALUE_TYPE *));
148 /* Compare reals by tree_code. */
149 extern bool real_compare PARAMS ((int, const REAL_VALUE_TYPE *,
150 const REAL_VALUE_TYPE *));
152 /* Determine whether a floating-point value X is infinite. */
153 extern bool real_isinf PARAMS ((const REAL_VALUE_TYPE *));
155 /* Determine whether a floating-point value X is a NaN. */
156 extern bool real_isnan PARAMS ((const REAL_VALUE_TYPE *));
158 /* Determine whether a floating-point value X is negative. */
159 extern bool real_isneg PARAMS ((const REAL_VALUE_TYPE *));
161 /* Determine whether a floating-point value X is minus zero. */
162 extern bool real_isnegzero PARAMS ((const REAL_VALUE_TYPE *));
164 /* Compare two floating-point objects for bitwise identity. */
165 extern bool real_identical PARAMS ((const REAL_VALUE_TYPE *,
166 const REAL_VALUE_TYPE *));
168 /* Extend or truncate to a new mode. */
169 extern void real_convert PARAMS ((REAL_VALUE_TYPE *,
171 const REAL_VALUE_TYPE *));
173 /* Return true if truncating to NEW is exact. */
174 extern bool exact_real_truncate PARAMS ((enum machine_mode,
175 const REAL_VALUE_TYPE *));
177 /* Render R as a decimal floating point constant. */
178 extern void real_to_decimal PARAMS ((char *, const REAL_VALUE_TYPE *,
179 size_t, size_t, int));
181 /* Render R as a hexadecimal floating point constant. */
182 extern void real_to_hexadecimal PARAMS ((char *, const REAL_VALUE_TYPE *,
183 size_t, size_t, int));
185 /* Render R as an integer. */
186 extern HOST_WIDE_INT real_to_integer PARAMS ((const REAL_VALUE_TYPE *));
187 extern void real_to_integer2 PARAMS ((HOST_WIDE_INT *, HOST_WIDE_INT *,
188 const REAL_VALUE_TYPE *));
190 /* Initialize R from a decimal or hexadecimal string. */
191 extern void real_from_string PARAMS ((REAL_VALUE_TYPE *, const char *));
193 /* Initialize R from an integer pair HIGH/LOW. */
194 extern void real_from_integer PARAMS ((REAL_VALUE_TYPE *,
196 unsigned HOST_WIDE_INT,
197 HOST_WIDE_INT, int));
199 extern long real_to_target_fmt PARAMS ((long *, const REAL_VALUE_TYPE *,
200 const struct real_format *));
201 extern long real_to_target PARAMS ((long *, const REAL_VALUE_TYPE *,
204 extern void real_from_target_fmt PARAMS ((REAL_VALUE_TYPE *, const long *,
205 const struct real_format *));
206 extern void real_from_target PARAMS ((REAL_VALUE_TYPE *, const long *,
209 extern void real_inf PARAMS ((REAL_VALUE_TYPE *));
211 extern bool real_nan PARAMS ((REAL_VALUE_TYPE *, const char *,
212 int, enum machine_mode));
214 extern void real_2expN PARAMS ((REAL_VALUE_TYPE *, int));
216 extern unsigned int real_hash PARAMS ((const REAL_VALUE_TYPE *));
219 /* Target formats defined in real.c. */
220 extern const struct real_format ieee_single_format;
221 extern const struct real_format ieee_double_format;
222 extern const struct real_format ieee_extended_motorola_format;
223 extern const struct real_format ieee_extended_intel_96_format;
224 extern const struct real_format ieee_extended_intel_96_round_53_format;
225 extern const struct real_format ieee_extended_intel_128_format;
226 extern const struct real_format ibm_extended_format;
227 extern const struct real_format ieee_quad_format;
228 extern const struct real_format vax_f_format;
229 extern const struct real_format vax_d_format;
230 extern const struct real_format vax_g_format;
231 extern const struct real_format i370_single_format;
232 extern const struct real_format i370_double_format;
233 extern const struct real_format c4x_single_format;
234 extern const struct real_format c4x_extended_format;
235 extern const struct real_format real_internal_format;
238 /* ====================================================================== */
241 #define REAL_ARITHMETIC(value, code, d1, d2) \
242 real_arithmetic (&(value), code, &(d1), &(d2))
244 #define REAL_VALUES_IDENTICAL(x, y) real_identical (&(x), &(y))
245 #define REAL_VALUES_EQUAL(x, y) real_compare (EQ_EXPR, &(x), &(y))
246 #define REAL_VALUES_LESS(x, y) real_compare (LT_EXPR, &(x), &(y))
248 /* Determine whether a floating-point value X is infinite. */
249 #define REAL_VALUE_ISINF(x) real_isinf (&(x))
251 /* Determine whether a floating-point value X is a NaN. */
252 #define REAL_VALUE_ISNAN(x) real_isnan (&(x))
254 /* Determine whether a floating-point value X is negative. */
255 #define REAL_VALUE_NEGATIVE(x) real_isneg (&(x))
257 /* Determine whether a floating-point value X is minus zero. */
258 #define REAL_VALUE_MINUS_ZERO(x) real_isnegzero (&(x))
260 /* IN is a REAL_VALUE_TYPE. OUT is an array of longs. */
261 #define REAL_VALUE_TO_TARGET_LONG_DOUBLE(IN, OUT) \
262 real_to_target (OUT, &(IN), \
263 mode_for_size (LONG_DOUBLE_TYPE_SIZE, MODE_FLOAT, 0))
265 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \
266 real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0))
268 /* IN is a REAL_VALUE_TYPE. OUT is a long. */
269 #define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT) \
270 ((OUT) = real_to_target (NULL, &(IN), mode_for_size (32, MODE_FLOAT, 0)))
272 #define REAL_VALUE_FROM_INT(r, lo, hi, mode) \
273 real_from_integer (&(r), mode, lo, hi, 0)
275 #define REAL_VALUE_FROM_UNSIGNED_INT(r, lo, hi, mode) \
276 real_from_integer (&(r), mode, lo, hi, 1)
278 extern REAL_VALUE_TYPE real_value_truncate PARAMS ((enum machine_mode,
281 #define REAL_VALUE_TO_INT(plow, phigh, r) \
282 real_to_integer2 (plow, phigh, &(r))
284 extern REAL_VALUE_TYPE real_arithmetic2 PARAMS ((int, const REAL_VALUE_TYPE *,
285 const REAL_VALUE_TYPE *));
287 #define REAL_VALUE_NEGATE(X) \
288 real_arithmetic2 (NEGATE_EXPR, &(X), NULL)
290 #define REAL_VALUE_ABS(X) \
291 real_arithmetic2 (ABS_EXPR, &(X), NULL)
293 extern int significand_size PARAMS ((enum machine_mode));
295 extern REAL_VALUE_TYPE real_from_string2 PARAMS ((const char *,
298 #define REAL_VALUE_ATOF(s, m) \
299 real_from_string2 (s, m)
301 #define CONST_DOUBLE_ATOF(s, m) \
302 CONST_DOUBLE_FROM_REAL_VALUE (real_from_string2 (s, m), m)
304 #define REAL_VALUE_FIX(r) \
305 real_to_integer (&(r))
307 /* ??? Not quite right. */
308 #define REAL_VALUE_UNSIGNED_FIX(r) \
309 real_to_integer (&(r))
311 /* ??? These were added for Paranoia support. */
313 /* Return floor log2(R). */
314 extern int real_exponent PARAMS ((const REAL_VALUE_TYPE *));
316 /* R = A * 2**EXP. */
317 extern void real_ldexp PARAMS ((REAL_VALUE_TYPE *,
318 const REAL_VALUE_TYPE *, int));
320 /* **** End of software floating point emulator interface macros **** */
322 /* Constant real values 0, 1, 2, and -1. */
324 extern REAL_VALUE_TYPE dconst0;
325 extern REAL_VALUE_TYPE dconst1;
326 extern REAL_VALUE_TYPE dconst2;
327 extern REAL_VALUE_TYPE dconstm1;
329 /* Function to return a real value (not a tree node)
330 from a given integer constant. */
331 REAL_VALUE_TYPE real_value_from_int_cst PARAMS ((union tree_node *,
334 /* Given a CONST_DOUBLE in FROM, store into TO the value it represents. */
335 #define REAL_VALUE_FROM_CONST_DOUBLE(to, from) \
336 memcpy (&(to), &CONST_DOUBLE_LOW ((from)), sizeof (REAL_VALUE_TYPE))
338 /* Return a CONST_DOUBLE with value R and mode M. */
339 #define CONST_DOUBLE_FROM_REAL_VALUE(r, m) \
340 const_double_from_real_value (r, m)
341 extern rtx const_double_from_real_value PARAMS ((REAL_VALUE_TYPE,
344 /* Replace R by 1/R in the given machine mode, if the result is exact. */
345 extern bool exact_real_inverse PARAMS ((enum machine_mode, REAL_VALUE_TYPE *));
347 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node. */
348 extern tree build_real PARAMS ((tree, REAL_VALUE_TYPE));
351 #endif /* ! GCC_REAL_H */