1 /* Translation of constants
2 Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
3 Contributed by Paul Brook
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
22 /* trans-const.c -- convert constant values */
26 #include "coretypes.h"
37 #include "trans-const.h"
38 #include "trans-types.h"
40 /* String constants. */
41 tree gfc_strconst_bounds;
42 tree gfc_strconst_fault;
43 tree gfc_strconst_wrong_return;
44 tree gfc_strconst_current_filename;
46 tree gfc_rank_cst[GFC_MAX_DIMENSIONS + 1];
48 /* Build a constant with given type from an int_cst. */
51 gfc_build_const (tree type, tree intval)
56 switch (TREE_CODE (type))
59 val = convert (type, intval);
63 val = build_real_from_int_cst (type, intval);
67 val = build_real_from_int_cst (TREE_TYPE (type), intval);
68 zero = build_real_from_int_cst (TREE_TYPE (type), integer_zero_node);
69 val = build_complex (type, val, zero);
79 gfc_build_string_const (int length, const char *s)
84 str = build_string (length, s);
85 len = build_int_cst (NULL_TREE, length, 0);
87 build_array_type (gfc_character1_type_node,
88 build_range_type (gfc_strlen_type_node,
89 integer_one_node, len));
93 /* Return a string constant with the given length. Used for static
94 initializers. The constant will be padded or truncated to match
98 gfc_conv_string_init (tree length, gfc_expr * expr)
105 assert (expr->expr_type == EXPR_CONSTANT);
106 assert (expr->ts.type == BT_CHARACTER && expr->ts.kind == 1);
107 assert (INTEGER_CST_P (length));
108 assert (TREE_INT_CST_HIGH (length) == 0);
110 len = TREE_INT_CST_LOW (length);
111 slen = expr->value.character.length;
115 s = gfc_getmem (len);
116 memcpy (s, expr->value.character.string, slen);
117 memset (&s[slen], ' ', len - slen);
118 str = gfc_build_string_const (len, s);
122 str = gfc_build_string_const (len, expr->value.character.string);
128 /* Create a tree node for the string length if it is constant. */
131 gfc_conv_const_charlen (gfc_charlen * cl)
133 if (cl->backend_decl)
136 if (cl->length && cl->length->expr_type == EXPR_CONSTANT)
138 cl->backend_decl = gfc_conv_mpz_to_tree (cl->length->value.integer,
139 cl->length->ts.kind);
144 gfc_init_constants (void)
148 for (n = 0; n <= GFC_MAX_DIMENSIONS; n++)
149 gfc_rank_cst[n] = build_int_cst (gfc_array_index_type, n, 0);
151 gfc_strconst_bounds = gfc_build_string_const (21, "Array bound mismatch");
154 gfc_build_string_const (30, "Array reference out of bounds");
156 gfc_strconst_wrong_return =
157 gfc_build_string_const (32, "Incorrect function return value");
159 gfc_strconst_current_filename =
160 gfc_build_string_const (strlen (gfc_option.source) + 1,
164 /* Converts a GMP integer into a backend tree node. */
166 gfc_conv_mpz_to_tree (mpz_t i, int kind)
169 unsigned HOST_WIDE_INT low;
171 if (mpz_fits_slong_p (i))
173 /* Note that HOST_WIDE_INT is never smaller than long. */
174 low = mpz_get_si (i);
175 high = mpz_sgn (i) < 0 ? -1 : 0;
179 /* Note that mp_limb_t can be anywhere from short to long long,
180 which gives us a nice variety of cases to choose from. */
182 if (sizeof (mp_limb_t) == sizeof (HOST_WIDE_INT))
184 low = mpz_getlimbn (i, 0);
185 high = mpz_getlimbn (i, 1);
187 else if (sizeof (mp_limb_t) == 2 * sizeof (HOST_WIDE_INT))
189 mp_limb_t limb0 = mpz_getlimbn (i, 0);
190 int shift = (sizeof (mp_limb_t) - sizeof (HOST_WIDE_INT)) * CHAR_BIT;
192 high = limb0 >> shift;
194 else if (sizeof (mp_limb_t) < sizeof (HOST_WIDE_INT))
196 int shift = sizeof (mp_limb_t) * CHAR_BIT;
197 int n, count = sizeof (HOST_WIDE_INT) / sizeof (mp_limb_t);
198 for (low = n = 0; n < count; ++n)
201 low |= mpz_getlimbn (i, n);
203 for (high = 0, n = count; n < 2*count; ++n)
206 high |= mpz_getlimbn (i, n);
210 /* By extracting limbs we constructed the absolute value of the
211 desired number. Negate if necessary. */
217 low = -low, high = ~high;
221 return build_int_cst (gfc_get_int_type (kind), low, high);
224 /* Converts a real constant into backend form. Uses an intermediate string
228 gfc_conv_mpfr_to_tree (mpfr_t f, int kind)
238 for (n = 0; gfc_real_kinds[n].kind != 0; n++)
240 if (gfc_real_kinds[n].kind == kind)
243 assert (gfc_real_kinds[n].kind);
245 n = MAX (abs (gfc_real_kinds[n].min_exponent),
246 abs (gfc_real_kinds[n].max_exponent));
255 if (kind == gfc_default_double_kind())
256 p = mpfr_get_str (NULL, &exp, 10, 17, f, GFC_RND_MODE);
258 p = mpfr_get_str (NULL, &exp, 10, 8, f, GFC_RND_MODE);
261 /* We also have one minus sign, "e", "." and a null terminator. */
262 q = (char *) gfc_getmem (strlen (p) + edigits + 4);
268 strcpy (&q[2], &p[1]);
278 sprintf (&q[strlen (q)], "%d", (int) exp);
285 type = gfc_get_real_type (kind);
286 res = build_real (type, REAL_VALUE_ATOF (q, TYPE_MODE (type)));
295 /* Translate any literal constant to a tree. Constants never have
296 pre or post chains. Character literal constants are special
297 special because they have a value and a length, so they cannot be
298 returned as a single tree. It is up to the caller to set the
299 length somewhere if necessary.
301 Returns the translated constant, or aborts if it gets a type it
305 gfc_conv_constant_to_tree (gfc_expr * expr)
307 assert (expr->expr_type == EXPR_CONSTANT);
309 switch (expr->ts.type)
312 return gfc_conv_mpz_to_tree (expr->value.integer, expr->ts.kind);
315 return gfc_conv_mpfr_to_tree (expr->value.real, expr->ts.kind);
318 return build_int_cst (NULL_TREE, expr->value.logical, 0);
322 tree real = gfc_conv_mpfr_to_tree (expr->value.complex.r,
324 tree imag = gfc_conv_mpfr_to_tree (expr->value.complex.i,
327 return build_complex (NULL_TREE, real, imag);
331 return gfc_build_string_const (expr->value.character.length,
332 expr->value.character.string);
335 fatal_error ("gfc_conv_constant_to_tree(): invalid type: %s",
336 gfc_typename (&expr->ts));
341 /* Like gfc_conv_constant_to_tree, but for a simplified expression.
342 We can handle character literal constants here as well. */
345 gfc_conv_constant (gfc_se * se, gfc_expr * expr)
347 assert (expr->expr_type == EXPR_CONSTANT);
351 assert (se->ss != gfc_ss_terminator);
352 assert (se->ss->type == GFC_SS_SCALAR);
353 assert (se->ss->expr == expr);
355 se->expr = se->ss->data.scalar.expr;
356 se->string_length = se->ss->data.scalar.string_length;
357 gfc_advance_se_ss_chain (se);
361 /* Translate the constant and put it in the simplifier structure. */
362 se->expr = gfc_conv_constant_to_tree (expr);
364 /* If this is a CHARACTER string, set its length in the simplifier
366 if (expr->ts.type == BT_CHARACTER)
367 se->string_length = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (se->expr)));