1 /* Translation of constants 2 Copyright (C) 2002-2020 Free Software Foundation, Inc. 3 Contributed by Paul Brook 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 3, 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 COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 /* trans-const.c -- convert constant values */ 22 23 #include "config.h" 24 #include "system.h" 25 #include "coretypes.h" 26 #include "tree.h" 27 #include "gfortran.h" 28 #include "options.h" 29 #include "trans.h" 30 #include "fold-const.h" 31 #include "stor-layout.h" 32 #include "realmpfr.h" 33 #include "trans-const.h" 34 #include "trans-types.h" 35 #include "target-memory.h" 36 37 tree gfc_rank_cst[GFC_MAX_DIMENSIONS + 1]; 38 39 /* Build a constant with given type from an int_cst. */ 40 41 tree 42 gfc_build_const (tree type, tree intval) 43 { 44 tree val; 45 tree zero; 46 47 switch (TREE_CODE (type)) 48 { 49 case INTEGER_TYPE: 50 val = convert (type, intval); 51 break; 52 53 case REAL_TYPE: 54 val = build_real_from_int_cst (type, intval); 55 break; 56 57 case COMPLEX_TYPE: 58 val = build_real_from_int_cst (TREE_TYPE (type), intval); 59 zero = build_real_from_int_cst (TREE_TYPE (type), integer_zero_node); 60 val = build_complex (type, val, zero); 61 break; 62 63 default: 64 gcc_unreachable (); 65 } 66 return val; 67 } 68 69 /* Build a string constant with C char type. */ 70 71 tree 72 gfc_build_string_const (size_t length, const char *s) 73 { 74 tree str; 75 tree len; 76 77 str = build_string (length, s); 78 len = size_int (length); 79 TREE_TYPE (str) = 80 build_array_type (gfc_character1_type_node, 81 build_range_type (gfc_charlen_type_node, 82 size_one_node, len)); 83 TYPE_STRING_FLAG (TREE_TYPE (str)) = 1; 84 return str; 85 } 86 87 88 /* Build a string constant with a type given by its kind; take care of 89 non-default character kinds. */ 90 91 tree 92 gfc_build_wide_string_const (int kind, size_t length, const gfc_char_t *string) 93 { 94 int i; 95 tree str, len; 96 size_t size; 97 char *s; 98 99 i = gfc_validate_kind (BT_CHARACTER, kind, false); 100 size = length * gfc_character_kinds[i].bit_size / 8; 101 102 s = XCNEWVAR (char, size); 103 gfc_encode_character (kind, length, string, (unsigned char *) s, size); 104 105 str = build_string (size, s); 106 free (s); 107 108 len = size_int (length); 109 TREE_TYPE (str) = 110 build_array_type (gfc_get_char_type (kind), 111 build_range_type (gfc_charlen_type_node, 112 size_one_node, len)); 113 TYPE_STRING_FLAG (TREE_TYPE (str)) = 1; 114 return str; 115 } 116 117 118 /* Build a Fortran character constant from a zero-terminated string. 119 There a two version of this function, one that translates the string 120 and one that doesn't. */ 121 tree 122 gfc_build_cstring_const (const char *string) 123 { 124 return gfc_build_string_const (strlen (string) + 1, string); 125 } 126 127 tree 128 gfc_build_localized_cstring_const (const char *msgid) 129 { 130 const char *localized = _(msgid); 131 return gfc_build_string_const (strlen (localized) + 1, localized); 132 } 133 134 135 /* Return a string constant with the given length. Used for static 136 initializers. The constant will be padded or truncated to match 137 length. */ 138 139 tree 140 gfc_conv_string_init (tree length, gfc_expr * expr) 141 { 142 gfc_char_t *s; 143 HOST_WIDE_INT len; 144 gfc_charlen_t slen; 145 tree str; 146 bool free_s = false; 147 148 gcc_assert (expr->expr_type == EXPR_CONSTANT); 149 gcc_assert (expr->ts.type == BT_CHARACTER); 150 gcc_assert (tree_fits_uhwi_p (length)); 151 152 len = TREE_INT_CST_LOW (length); 153 slen = expr->value.character.length; 154 155 if (len > slen) 156 { 157 s = gfc_get_wide_string (len); 158 memcpy (s, expr->value.character.string, slen * sizeof (gfc_char_t)); 159 gfc_wide_memset (&s[slen], ' ', len - slen); 160 free_s = true; 161 } 162 else 163 s = expr->value.character.string; 164 165 str = gfc_build_wide_string_const (expr->ts.kind, len, s); 166 167 if (free_s) 168 free (s); 169 170 return str; 171 } 172 173 174 /* Create a tree node for the string length if it is constant. */ 175 176 void 177 gfc_conv_const_charlen (gfc_charlen * cl) 178 { 179 if (!cl || cl->backend_decl) 180 return; 181 182 if (cl->length && cl->length->expr_type == EXPR_CONSTANT) 183 { 184 cl->backend_decl = gfc_conv_mpz_to_tree (cl->length->value.integer, 185 cl->length->ts.kind); 186 cl->backend_decl = fold_convert (gfc_charlen_type_node, 187 cl->backend_decl); 188 } 189 } 190 191 void 192 gfc_init_constants (void) 193 { 194 int n; 195 196 for (n = 0; n <= GFC_MAX_DIMENSIONS; n++) 197 gfc_rank_cst[n] = build_int_cst (gfc_array_index_type, n); 198 } 199 200 /* Converts a GMP integer into a backend tree node. */ 201 202 tree 203 gfc_conv_mpz_to_tree (mpz_t i, int kind) 204 { 205 wide_int val = wi::from_mpz (gfc_get_int_type (kind), i, true); 206 return wide_int_to_tree (gfc_get_int_type (kind), val); 207 } 208 209 210 /* Convert a GMP integer into a tree node of type given by the type 211 argument. */ 212 213 tree 214 gfc_conv_mpz_to_tree_type (mpz_t i, const tree type) 215 { 216 const wide_int val = wi::from_mpz (type, i, true); 217 return wide_int_to_tree (type, val); 218 } 219 220 221 /* Converts a backend tree into a GMP integer. */ 222 223 void 224 gfc_conv_tree_to_mpz (mpz_t i, tree source) 225 { 226 wi::to_mpz (wi::to_wide (source), i, TYPE_SIGN (TREE_TYPE (source))); 227 } 228 229 /* Converts a real constant into backend form. */ 230 231 tree 232 gfc_conv_mpfr_to_tree (mpfr_t f, int kind, int is_snan) 233 { 234 tree type; 235 int n; 236 REAL_VALUE_TYPE real; 237 238 n = gfc_validate_kind (BT_REAL, kind, false); 239 gcc_assert (gfc_real_kinds[n].radix == 2); 240 241 type = gfc_get_real_type (kind); 242 if (mpfr_nan_p (f) && is_snan) 243 real_from_string (&real, "SNaN"); 244 else 245 real_from_mpfr (&real, f, type, GFC_RND_MODE); 246 247 return build_real (type, real); 248 } 249 250 /* Returns a real constant that is +Infinity if the target 251 supports infinities for this floating-point mode, and 252 +HUGE_VAL otherwise (the largest representable number). */ 253 254 tree 255 gfc_build_inf_or_huge (tree type, int kind) 256 { 257 if (HONOR_INFINITIES (TYPE_MODE (type))) 258 { 259 REAL_VALUE_TYPE real; 260 real_inf (&real); 261 return build_real (type, real); 262 } 263 else 264 { 265 int k = gfc_validate_kind (BT_REAL, kind, false); 266 return gfc_conv_mpfr_to_tree (gfc_real_kinds[k].huge, kind, 0); 267 } 268 } 269 270 /* Returns a floating-point NaN of a given type. */ 271 272 tree 273 gfc_build_nan (tree type, const char *str) 274 { 275 REAL_VALUE_TYPE real; 276 real_nan (&real, str, 1, TYPE_MODE (type)); 277 return build_real (type, real); 278 } 279 280 /* Converts a backend tree into a real constant. */ 281 282 void 283 gfc_conv_tree_to_mpfr (mpfr_ptr f, tree source) 284 { 285 mpfr_from_real (f, TREE_REAL_CST_PTR (source), GFC_RND_MODE); 286 } 287 288 /* Translate any literal constant to a tree. Constants never have 289 pre or post chains. Character literal constants are special 290 special because they have a value and a length, so they cannot be 291 returned as a single tree. It is up to the caller to set the 292 length somewhere if necessary. 293 294 Returns the translated constant, or aborts if it gets a type it 295 can't handle. */ 296 297 tree 298 gfc_conv_constant_to_tree (gfc_expr * expr) 299 { 300 tree res; 301 302 gcc_assert (expr->expr_type == EXPR_CONSTANT); 303 304 /* If it is has a prescribed memory representation, we build a string 305 constant and VIEW_CONVERT to its type. */ 306 307 switch (expr->ts.type) 308 { 309 case BT_INTEGER: 310 if (expr->representation.string) 311 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR, 312 gfc_get_int_type (expr->ts.kind), 313 gfc_build_string_const (expr->representation.length, 314 expr->representation.string)); 315 else 316 return gfc_conv_mpz_to_tree (expr->value.integer, expr->ts.kind); 317 318 case BT_REAL: 319 if (expr->representation.string) 320 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR, 321 gfc_get_real_type (expr->ts.kind), 322 gfc_build_string_const (expr->representation.length, 323 expr->representation.string)); 324 else 325 return gfc_conv_mpfr_to_tree (expr->value.real, expr->ts.kind, expr->is_snan); 326 327 case BT_LOGICAL: 328 if (expr->representation.string) 329 { 330 tree tmp = fold_build1_loc (input_location, VIEW_CONVERT_EXPR, 331 gfc_get_int_type (expr->ts.kind), 332 gfc_build_string_const (expr->representation.length, 333 expr->representation.string)); 334 if (!integer_zerop (tmp) && !integer_onep (tmp)) 335 gfc_warning (flag_dec_char_conversions ? OPT_Wsurprising : 0, 336 "Assigning value other than 0 or 1 to LOGICAL has " 337 "undefined result at %L", &expr->where); 338 return fold_convert (gfc_get_logical_type (expr->ts.kind), tmp); 339 } 340 else 341 return build_int_cst (gfc_get_logical_type (expr->ts.kind), 342 expr->value.logical); 343 344 case BT_COMPLEX: 345 if (expr->representation.string) 346 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR, 347 gfc_get_complex_type (expr->ts.kind), 348 gfc_build_string_const (expr->representation.length, 349 expr->representation.string)); 350 else 351 { 352 tree real = gfc_conv_mpfr_to_tree (mpc_realref (expr->value.complex), 353 expr->ts.kind, expr->is_snan); 354 tree imag = gfc_conv_mpfr_to_tree (mpc_imagref (expr->value.complex), 355 expr->ts.kind, expr->is_snan); 356 357 return build_complex (gfc_typenode_for_spec (&expr->ts), 358 real, imag); 359 } 360 361 case BT_CHARACTER: 362 res = gfc_build_wide_string_const (expr->ts.kind, 363 expr->value.character.length, 364 expr->value.character.string); 365 return res; 366 367 case BT_HOLLERITH: 368 return gfc_build_string_const (expr->representation.length, 369 expr->representation.string); 370 371 default: 372 gcc_unreachable (); 373 } 374 } 375 376 377 /* Like gfc_conv_constant_to_tree, but for a simplified expression. 378 We can handle character literal constants here as well. */ 379 380 void 381 gfc_conv_constant (gfc_se * se, gfc_expr * expr) 382 { 383 gfc_ss *ss; 384 385 /* We may be receiving an expression for C_NULL_PTR or C_NULL_FUNPTR. If 386 so, the expr_type will not yet be an EXPR_CONSTANT. We need to make 387 it so here. */ 388 if (expr->ts.type == BT_DERIVED && expr->ts.u.derived 389 && expr->ts.u.derived->attr.is_iso_c) 390 { 391 if (expr->symtree->n.sym->intmod_sym_id == ISOCBINDING_NULL_PTR 392 || expr->symtree->n.sym->intmod_sym_id == ISOCBINDING_NULL_FUNPTR) 393 { 394 /* Create a new EXPR_CONSTANT expression for our local uses. */ 395 expr = gfc_get_int_expr (gfc_default_integer_kind, NULL, 0); 396 } 397 } 398 399 if (expr->expr_type != EXPR_CONSTANT) 400 { 401 gfc_expr *e = gfc_get_int_expr (gfc_default_integer_kind, NULL, 0); 402 gfc_error ("non-constant initialization expression at %L", &expr->where); 403 se->expr = gfc_conv_constant_to_tree (e); 404 return; 405 } 406 407 ss = se->ss; 408 if (ss != NULL) 409 { 410 gfc_ss_info *ss_info; 411 412 ss_info = ss->info; 413 gcc_assert (ss != gfc_ss_terminator); 414 gcc_assert (ss_info->type == GFC_SS_SCALAR); 415 gcc_assert (ss_info->expr == expr); 416 417 se->expr = ss_info->data.scalar.value; 418 se->string_length = ss_info->string_length; 419 gfc_advance_se_ss_chain (se); 420 return; 421 } 422 423 /* Translate the constant and put it in the simplifier structure. */ 424 se->expr = gfc_conv_constant_to_tree (expr); 425 426 /* If this is a CHARACTER string, set its length in the simplifier 427 structure, too. */ 428 if (expr->ts.type == BT_CHARACTER) 429 se->string_length = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (se->expr))); 430 } 431