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. 4 5 This file is part of GCC. 6 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 10 version. 11 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 15 for more details. 16 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 20 02111-1307, USA. */ 21 22 #ifndef GCC_REAL_H 23 #define GCC_REAL_H 24 25 #include "machmode.h" 26 27 /* An expanded form of the represented number. */ 28 29 /* Enumerate the special cases of numbers that we encounter. */ 30 enum real_value_class { 31 rvc_zero, 32 rvc_normal, 33 rvc_inf, 34 rvc_nan 35 }; 36 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)) 42 43 struct real_value GTY(()) 44 { 45 ENUM_BITFIELD (real_value_class) class : 2; 46 unsigned int sign : 1; 47 signed int exp : EXP_BITS; 48 unsigned long sig[SIGSZ]; 49 }; 50 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 55 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. */ 59 60 #define REAL_VALUE_TYPE_SIZE (SIGNIFICAND_BITS + 32) 61 #define REAL_WIDTH \ 62 (REAL_VALUE_TYPE_SIZE/HOST_BITS_PER_WIDE_INT \ 63 + (REAL_VALUE_TYPE_SIZE%HOST_BITS_PER_WIDE_INT ? 1 : 0)) /* round up */ 64 65 /* Verify the guess. */ 66 extern char test_real_width 67 [sizeof(REAL_VALUE_TYPE) <= REAL_WIDTH*sizeof(HOST_WIDE_INT) ? 1 : -1]; 68 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). 72 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. */ 75 76 #if REAL_WIDTH == 1 77 # define CONST_DOUBLE_FORMAT "ww" 78 #else 79 # if REAL_WIDTH == 2 80 # define CONST_DOUBLE_FORMAT "ww" 81 # else 82 # if REAL_WIDTH == 3 83 # define CONST_DOUBLE_FORMAT "www" 84 # else 85 # if REAL_WIDTH == 4 86 # define CONST_DOUBLE_FORMAT "wwww" 87 # else 88 # if REAL_WIDTH == 5 89 # define CONST_DOUBLE_FORMAT "wwwww" 90 # else 91 # if REAL_WIDTH == 6 92 # define CONST_DOUBLE_FORMAT "wwwwww" 93 # else 94 #error "REAL_WIDTH > 6 not supported" 95 # endif 96 # endif 97 # endif 98 # endif 99 # endif 100 #endif 101 102 103 /* Describes the properties of the specific target format in use. */ 104 struct real_format 105 { 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 *, 110 const long *)); 111 112 /* The radix of the exponent and digits of the significand. */ 113 int b; 114 115 /* log2(b). */ 116 int log2_b; 117 118 /* Size of the significand in digits of radix B. */ 119 int p; 120 121 /* The minimum negative integer, x, such that b**(x-1) is normalized. */ 122 int emin; 123 124 /* The maximum integer, x, such that b**(x-1) is representable. */ 125 int emax; 126 127 /* Properties of the format. */ 128 bool has_nans; 129 bool has_inf; 130 bool has_denorm; 131 bool has_signed_zero; 132 bool qnan_msb_set; 133 }; 134 135 136 /* 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]; 139 140 141 /* Declare functions in real.c. */ 142 143 /* 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 *)); 147 148 /* Compare reals by tree_code. */ 149 extern bool real_compare PARAMS ((int, const REAL_VALUE_TYPE *, 150 const REAL_VALUE_TYPE *)); 151 152 /* Determine whether a floating-point value X is infinite. */ 153 extern bool real_isinf PARAMS ((const REAL_VALUE_TYPE *)); 154 155 /* Determine whether a floating-point value X is a NaN. */ 156 extern bool real_isnan PARAMS ((const REAL_VALUE_TYPE *)); 157 158 /* Determine whether a floating-point value X is negative. */ 159 extern bool real_isneg PARAMS ((const REAL_VALUE_TYPE *)); 160 161 /* Determine whether a floating-point value X is minus zero. */ 162 extern bool real_isnegzero PARAMS ((const REAL_VALUE_TYPE *)); 163 164 /* Compare two floating-point objects for bitwise identity. */ 165 extern bool real_identical PARAMS ((const REAL_VALUE_TYPE *, 166 const REAL_VALUE_TYPE *)); 167 168 /* Extend or truncate to a new mode. */ 169 extern void real_convert PARAMS ((REAL_VALUE_TYPE *, 170 enum machine_mode, 171 const REAL_VALUE_TYPE *)); 172 173 /* Return true if truncating to NEW is exact. */ 174 extern bool exact_real_truncate PARAMS ((enum machine_mode, 175 const REAL_VALUE_TYPE *)); 176 177 /* 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)); 180 181 /* 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)); 184 185 /* 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 *)); 189 190 /* Initialize R from a decimal or hexadecimal string. */ 191 extern void real_from_string PARAMS ((REAL_VALUE_TYPE *, const char *)); 192 193 /* Initialize R from an integer pair HIGH/LOW. */ 194 extern void real_from_integer PARAMS ((REAL_VALUE_TYPE *, 195 enum machine_mode, 196 unsigned HOST_WIDE_INT, 197 HOST_WIDE_INT, int)); 198 199 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 *, 202 enum machine_mode)); 203 204 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 *, 207 enum machine_mode)); 208 209 extern void real_inf PARAMS ((REAL_VALUE_TYPE *)); 210 211 extern bool real_nan PARAMS ((REAL_VALUE_TYPE *, const char *, 212 int, enum machine_mode)); 213 214 extern void real_2expN PARAMS ((REAL_VALUE_TYPE *, int)); 215 216 extern unsigned int real_hash PARAMS ((const REAL_VALUE_TYPE *)); 217 218 219 /* 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; 236 237 238 /* ====================================================================== */ 239 /* Crap. */ 240 241 #define REAL_ARITHMETIC(value, code, d1, d2) \ 242 real_arithmetic (&(value), code, &(d1), &(d2)) 243 244 #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)) 247 248 /* Determine whether a floating-point value X is infinite. */ 249 #define REAL_VALUE_ISINF(x) real_isinf (&(x)) 250 251 /* Determine whether a floating-point value X is a NaN. */ 252 #define REAL_VALUE_ISNAN(x) real_isnan (&(x)) 253 254 /* Determine whether a floating-point value X is negative. */ 255 #define REAL_VALUE_NEGATIVE(x) real_isneg (&(x)) 256 257 /* Determine whether a floating-point value X is minus zero. */ 258 #define REAL_VALUE_MINUS_ZERO(x) real_isnegzero (&(x)) 259 260 /* 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)) 264 265 #define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT) \ 266 real_to_target (OUT, &(IN), mode_for_size (64, MODE_FLOAT, 0)) 267 268 /* 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))) 271 272 #define REAL_VALUE_FROM_INT(r, lo, hi, mode) \ 273 real_from_integer (&(r), mode, lo, hi, 0) 274 275 #define REAL_VALUE_FROM_UNSIGNED_INT(r, lo, hi, mode) \ 276 real_from_integer (&(r), mode, lo, hi, 1) 277 278 extern REAL_VALUE_TYPE real_value_truncate PARAMS ((enum machine_mode, 279 REAL_VALUE_TYPE)); 280 281 #define REAL_VALUE_TO_INT(plow, phigh, r) \ 282 real_to_integer2 (plow, phigh, &(r)) 283 284 extern REAL_VALUE_TYPE real_arithmetic2 PARAMS ((int, const REAL_VALUE_TYPE *, 285 const REAL_VALUE_TYPE *)); 286 287 #define REAL_VALUE_NEGATE(X) \ 288 real_arithmetic2 (NEGATE_EXPR, &(X), NULL) 289 290 #define REAL_VALUE_ABS(X) \ 291 real_arithmetic2 (ABS_EXPR, &(X), NULL) 292 293 extern int significand_size PARAMS ((enum machine_mode)); 294 295 extern REAL_VALUE_TYPE real_from_string2 PARAMS ((const char *, 296 enum machine_mode)); 297 298 #define REAL_VALUE_ATOF(s, m) \ 299 real_from_string2 (s, m) 300 301 #define CONST_DOUBLE_ATOF(s, m) \ 302 CONST_DOUBLE_FROM_REAL_VALUE (real_from_string2 (s, m), m) 303 304 #define REAL_VALUE_FIX(r) \ 305 real_to_integer (&(r)) 306 307 /* ??? Not quite right. */ 308 #define REAL_VALUE_UNSIGNED_FIX(r) \ 309 real_to_integer (&(r)) 310 311 /* ??? These were added for Paranoia support. */ 312 313 /* Return floor log2(R). */ 314 extern int real_exponent PARAMS ((const REAL_VALUE_TYPE *)); 315 316 /* R = A * 2**EXP. */ 317 extern void real_ldexp PARAMS ((REAL_VALUE_TYPE *, 318 const REAL_VALUE_TYPE *, int)); 319 320 /* **** End of software floating point emulator interface macros **** */ 321 322 /* Constant real values 0, 1, 2, and -1. */ 323 324 extern REAL_VALUE_TYPE dconst0; 325 extern REAL_VALUE_TYPE dconst1; 326 extern REAL_VALUE_TYPE dconst2; 327 extern REAL_VALUE_TYPE dconstm1; 328 329 /* 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 *, 332 union tree_node *)); 333 334 /* 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)) 337 338 /* 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, 342 enum machine_mode)); 343 344 /* 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 *)); 346 347 /* In tree.c: wrap up a REAL_VALUE_TYPE in a tree node. */ 348 extern tree build_real PARAMS ((tree, REAL_VALUE_TYPE)); 349 350 351 #endif /* ! GCC_REAL_H */ 352