1 /* Translation of constants
2 Copyright (C) 2002-2019 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 "trans.h"
29 #include "fold-const.h"
30 #include "stor-layout.h"
31 #include "realmpfr.h"
32 #include "trans-const.h"
33 #include "trans-types.h"
34 #include "target-memory.h"
35
36 tree gfc_rank_cst[GFC_MAX_DIMENSIONS + 1];
37
38 /* Build a constant with given type from an int_cst. */
39
40 tree
gfc_build_const(tree type,tree intval)41 gfc_build_const (tree type, tree intval)
42 {
43 tree val;
44 tree zero;
45
46 switch (TREE_CODE (type))
47 {
48 case INTEGER_TYPE:
49 val = convert (type, intval);
50 break;
51
52 case REAL_TYPE:
53 val = build_real_from_int_cst (type, intval);
54 break;
55
56 case COMPLEX_TYPE:
57 val = build_real_from_int_cst (TREE_TYPE (type), intval);
58 zero = build_real_from_int_cst (TREE_TYPE (type), integer_zero_node);
59 val = build_complex (type, val, zero);
60 break;
61
62 default:
63 gcc_unreachable ();
64 }
65 return val;
66 }
67
68 /* Build a string constant with C char type. */
69
70 tree
gfc_build_string_const(size_t length,const char * s)71 gfc_build_string_const (size_t length, const char *s)
72 {
73 tree str;
74 tree len;
75
76 str = build_string (length, s);
77 len = size_int (length);
78 TREE_TYPE (str) =
79 build_array_type (gfc_character1_type_node,
80 build_range_type (gfc_charlen_type_node,
81 size_one_node, len));
82 TYPE_STRING_FLAG (TREE_TYPE (str)) = 1;
83 return str;
84 }
85
86
87 /* Build a string constant with a type given by its kind; take care of
88 non-default character kinds. */
89
90 tree
gfc_build_wide_string_const(int kind,size_t length,const gfc_char_t * string)91 gfc_build_wide_string_const (int kind, size_t length, const gfc_char_t *string)
92 {
93 int i;
94 tree str, len;
95 size_t size;
96 char *s;
97
98 i = gfc_validate_kind (BT_CHARACTER, kind, false);
99 size = length * gfc_character_kinds[i].bit_size / 8;
100
101 s = XCNEWVAR (char, size);
102 gfc_encode_character (kind, length, string, (unsigned char *) s, size);
103
104 str = build_string (size, s);
105 free (s);
106
107 len = size_int (length);
108 TREE_TYPE (str) =
109 build_array_type (gfc_get_char_type (kind),
110 build_range_type (gfc_charlen_type_node,
111 size_one_node, len));
112 TYPE_STRING_FLAG (TREE_TYPE (str)) = 1;
113 return str;
114 }
115
116
117 /* Build a Fortran character constant from a zero-terminated string.
118 There a two version of this function, one that translates the string
119 and one that doesn't. */
120 tree
gfc_build_cstring_const(const char * string)121 gfc_build_cstring_const (const char *string)
122 {
123 return gfc_build_string_const (strlen (string) + 1, string);
124 }
125
126 tree
gfc_build_localized_cstring_const(const char * msgid)127 gfc_build_localized_cstring_const (const char *msgid)
128 {
129 const char *localized = _(msgid);
130 return gfc_build_string_const (strlen (localized) + 1, localized);
131 }
132
133
134 /* Return a string constant with the given length. Used for static
135 initializers. The constant will be padded or truncated to match
136 length. */
137
138 tree
gfc_conv_string_init(tree length,gfc_expr * expr)139 gfc_conv_string_init (tree length, gfc_expr * expr)
140 {
141 gfc_char_t *s;
142 HOST_WIDE_INT len;
143 gfc_charlen_t slen;
144 tree str;
145 bool free_s = false;
146
147 gcc_assert (expr->expr_type == EXPR_CONSTANT);
148 gcc_assert (expr->ts.type == BT_CHARACTER);
149 gcc_assert (tree_fits_uhwi_p (length));
150
151 len = TREE_INT_CST_LOW (length);
152 slen = expr->value.character.length;
153
154 if (len > slen)
155 {
156 s = gfc_get_wide_string (len);
157 memcpy (s, expr->value.character.string, slen * sizeof (gfc_char_t));
158 gfc_wide_memset (&s[slen], ' ', len - slen);
159 free_s = true;
160 }
161 else
162 s = expr->value.character.string;
163
164 str = gfc_build_wide_string_const (expr->ts.kind, len, s);
165
166 if (free_s)
167 free (s);
168
169 return str;
170 }
171
172
173 /* Create a tree node for the string length if it is constant. */
174
175 void
gfc_conv_const_charlen(gfc_charlen * cl)176 gfc_conv_const_charlen (gfc_charlen * cl)
177 {
178 if (!cl || cl->backend_decl)
179 return;
180
181 if (cl->length && cl->length->expr_type == EXPR_CONSTANT)
182 {
183 cl->backend_decl = gfc_conv_mpz_to_tree (cl->length->value.integer,
184 cl->length->ts.kind);
185 cl->backend_decl = fold_convert (gfc_charlen_type_node,
186 cl->backend_decl);
187 }
188 }
189
190 void
gfc_init_constants(void)191 gfc_init_constants (void)
192 {
193 int n;
194
195 for (n = 0; n <= GFC_MAX_DIMENSIONS; n++)
196 gfc_rank_cst[n] = build_int_cst (gfc_array_index_type, n);
197 }
198
199 /* Converts a GMP integer into a backend tree node. */
200
201 tree
gfc_conv_mpz_to_tree(mpz_t i,int kind)202 gfc_conv_mpz_to_tree (mpz_t i, int kind)
203 {
204 wide_int val = wi::from_mpz (gfc_get_int_type (kind), i, true);
205 return wide_int_to_tree (gfc_get_int_type (kind), val);
206 }
207
208
209 /* Convert a GMP integer into a tree node of type given by the type
210 argument. */
211
212 tree
gfc_conv_mpz_to_tree_type(mpz_t i,const tree type)213 gfc_conv_mpz_to_tree_type (mpz_t i, const tree type)
214 {
215 const wide_int val = wi::from_mpz (type, i, true);
216 return wide_int_to_tree (type, val);
217 }
218
219
220 /* Converts a backend tree into a GMP integer. */
221
222 void
gfc_conv_tree_to_mpz(mpz_t i,tree source)223 gfc_conv_tree_to_mpz (mpz_t i, tree source)
224 {
225 wi::to_mpz (wi::to_wide (source), i, TYPE_SIGN (TREE_TYPE (source)));
226 }
227
228 /* Converts a real constant into backend form. */
229
230 tree
gfc_conv_mpfr_to_tree(mpfr_t f,int kind,int is_snan)231 gfc_conv_mpfr_to_tree (mpfr_t f, int kind, int is_snan)
232 {
233 tree type;
234 int n;
235 REAL_VALUE_TYPE real;
236
237 n = gfc_validate_kind (BT_REAL, kind, false);
238 gcc_assert (gfc_real_kinds[n].radix == 2);
239
240 type = gfc_get_real_type (kind);
241 if (mpfr_nan_p (f) && is_snan)
242 real_from_string (&real, "SNaN");
243 else
244 real_from_mpfr (&real, f, type, GFC_RND_MODE);
245
246 return build_real (type, real);
247 }
248
249 /* Returns a real constant that is +Infinity if the target
250 supports infinities for this floating-point mode, and
251 +HUGE_VAL otherwise (the largest representable number). */
252
253 tree
gfc_build_inf_or_huge(tree type,int kind)254 gfc_build_inf_or_huge (tree type, int kind)
255 {
256 if (HONOR_INFINITIES (TYPE_MODE (type)))
257 {
258 REAL_VALUE_TYPE real;
259 real_inf (&real);
260 return build_real (type, real);
261 }
262 else
263 {
264 int k = gfc_validate_kind (BT_REAL, kind, false);
265 return gfc_conv_mpfr_to_tree (gfc_real_kinds[k].huge, kind, 0);
266 }
267 }
268
269 /* Returns a floating-point NaN of a given type. */
270
271 tree
gfc_build_nan(tree type,const char * str)272 gfc_build_nan (tree type, const char *str)
273 {
274 REAL_VALUE_TYPE real;
275 real_nan (&real, str, 1, TYPE_MODE (type));
276 return build_real (type, real);
277 }
278
279 /* Converts a backend tree into a real constant. */
280
281 void
gfc_conv_tree_to_mpfr(mpfr_ptr f,tree source)282 gfc_conv_tree_to_mpfr (mpfr_ptr f, tree source)
283 {
284 mpfr_from_real (f, TREE_REAL_CST_PTR (source), GFC_RND_MODE);
285 }
286
287 /* Translate any literal constant to a tree. Constants never have
288 pre or post chains. Character literal constants are special
289 special because they have a value and a length, so they cannot be
290 returned as a single tree. It is up to the caller to set the
291 length somewhere if necessary.
292
293 Returns the translated constant, or aborts if it gets a type it
294 can't handle. */
295
296 tree
gfc_conv_constant_to_tree(gfc_expr * expr)297 gfc_conv_constant_to_tree (gfc_expr * expr)
298 {
299 tree res;
300
301 gcc_assert (expr->expr_type == EXPR_CONSTANT);
302
303 /* If it is has a prescribed memory representation, we build a string
304 constant and VIEW_CONVERT to its type. */
305
306 switch (expr->ts.type)
307 {
308 case BT_INTEGER:
309 if (expr->representation.string)
310 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR,
311 gfc_get_int_type (expr->ts.kind),
312 gfc_build_string_const (expr->representation.length,
313 expr->representation.string));
314 else
315 return gfc_conv_mpz_to_tree (expr->value.integer, expr->ts.kind);
316
317 case BT_REAL:
318 if (expr->representation.string)
319 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR,
320 gfc_get_real_type (expr->ts.kind),
321 gfc_build_string_const (expr->representation.length,
322 expr->representation.string));
323 else
324 return gfc_conv_mpfr_to_tree (expr->value.real, expr->ts.kind, expr->is_snan);
325
326 case BT_LOGICAL:
327 if (expr->representation.string)
328 {
329 tree tmp = fold_build1_loc (input_location, VIEW_CONVERT_EXPR,
330 gfc_get_int_type (expr->ts.kind),
331 gfc_build_string_const (expr->representation.length,
332 expr->representation.string));
333 if (!integer_zerop (tmp) && !integer_onep (tmp))
334 gfc_warning (0, "Assigning value other than 0 or 1 to LOGICAL"
335 " has undefined result at %L", &expr->where);
336 return fold_convert (gfc_get_logical_type (expr->ts.kind), tmp);
337 }
338 else
339 return build_int_cst (gfc_get_logical_type (expr->ts.kind),
340 expr->value.logical);
341
342 case BT_COMPLEX:
343 if (expr->representation.string)
344 return fold_build1_loc (input_location, VIEW_CONVERT_EXPR,
345 gfc_get_complex_type (expr->ts.kind),
346 gfc_build_string_const (expr->representation.length,
347 expr->representation.string));
348 else
349 {
350 tree real = gfc_conv_mpfr_to_tree (mpc_realref (expr->value.complex),
351 expr->ts.kind, expr->is_snan);
352 tree imag = gfc_conv_mpfr_to_tree (mpc_imagref (expr->value.complex),
353 expr->ts.kind, expr->is_snan);
354
355 return build_complex (gfc_typenode_for_spec (&expr->ts),
356 real, imag);
357 }
358
359 case BT_CHARACTER:
360 res = gfc_build_wide_string_const (expr->ts.kind,
361 expr->value.character.length,
362 expr->value.character.string);
363 return res;
364
365 case BT_HOLLERITH:
366 return gfc_build_string_const (expr->representation.length,
367 expr->representation.string);
368
369 default:
370 gcc_unreachable ();
371 }
372 }
373
374
375 /* Like gfc_conv_constant_to_tree, but for a simplified expression.
376 We can handle character literal constants here as well. */
377
378 void
gfc_conv_constant(gfc_se * se,gfc_expr * expr)379 gfc_conv_constant (gfc_se * se, gfc_expr * expr)
380 {
381 gfc_ss *ss;
382
383 /* We may be receiving an expression for C_NULL_PTR or C_NULL_FUNPTR. If
384 so, the expr_type will not yet be an EXPR_CONSTANT. We need to make
385 it so here. */
386 if (expr->ts.type == BT_DERIVED && expr->ts.u.derived
387 && expr->ts.u.derived->attr.is_iso_c)
388 {
389 if (expr->symtree->n.sym->intmod_sym_id == ISOCBINDING_NULL_PTR
390 || expr->symtree->n.sym->intmod_sym_id == ISOCBINDING_NULL_FUNPTR)
391 {
392 /* Create a new EXPR_CONSTANT expression for our local uses. */
393 expr = gfc_get_int_expr (gfc_default_integer_kind, NULL, 0);
394 }
395 }
396
397 if (expr->expr_type != EXPR_CONSTANT)
398 {
399 gfc_expr *e = gfc_get_int_expr (gfc_default_integer_kind, NULL, 0);
400 gfc_error ("non-constant initialization expression at %L", &expr->where);
401 se->expr = gfc_conv_constant_to_tree (e);
402 return;
403 }
404
405 ss = se->ss;
406 if (ss != NULL)
407 {
408 gfc_ss_info *ss_info;
409
410 ss_info = ss->info;
411 gcc_assert (ss != gfc_ss_terminator);
412 gcc_assert (ss_info->type == GFC_SS_SCALAR);
413 gcc_assert (ss_info->expr == expr);
414
415 se->expr = ss_info->data.scalar.value;
416 se->string_length = ss_info->string_length;
417 gfc_advance_se_ss_chain (se);
418 return;
419 }
420
421 /* Translate the constant and put it in the simplifier structure. */
422 se->expr = gfc_conv_constant_to_tree (expr);
423
424 /* If this is a CHARACTER string, set its length in the simplifier
425 structure, too. */
426 if (expr->ts.type == BT_CHARACTER)
427 se->string_length = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (se->expr)));
428 }
429