1 /* This module handles expression trees.
2 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 Free Software Foundation, Inc.
5 Written by Steve Chamberlain of Cygnus Support <sac@cygnus.com>.
7 This file is part of GLD, the Gnu Linker.
9 GLD is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GLD is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GLD; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 /* This module is in charge of working out the contents of expressions.
26 It has to keep track of the relative/absness of a symbol etc. This
27 is done by keeping all values in a struct (an etree_value_type)
28 which contains a value, a section to which it is relative and a
41 #include "libiberty.h"
42 #include "safe-ctype.h"
44 static etree_value_type exp_fold_tree_no_dot
45 (etree_type *, lang_output_section_statement_type *, lang_phase_type);
46 static bfd_vma align_n
49 struct exp_data_seg exp_data_seg;
51 /* Print the string representation of the given token. Surround it
52 with spaces if INFIX_P is TRUE. */
55 exp_print_token (token_code_type code, int infix_p)
89 { SECTIONS, "SECTIONS" },
90 { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
92 { DEFINED, "DEFINED" },
93 { TARGET_K, "TARGET" },
94 { SEARCH_DIR, "SEARCH_DIR" },
100 { LOADADDR, "LOADADDR" },
102 { REL, "relocatable" },
103 { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
104 { DATA_SEGMENT_END, "DATA_SEGMENT_END" }
108 for (idx = 0; idx < ARRAY_SIZE (table); idx++)
109 if (table[idx].code == code)
113 fputc (' ', config.map_file);
115 if (idx < ARRAY_SIZE (table))
116 fputs (table[idx].name, config.map_file);
118 fputc (code, config.map_file);
120 fprintf (config.map_file, "<code %d>", code);
123 fputc (' ', config.map_file);
127 make_abs (etree_value_type *ptr)
129 asection *s = ptr->section->bfd_section;
130 ptr->value += s->vma;
131 ptr->section = abs_output_section;
134 static etree_value_type
135 new_abs (bfd_vma value)
137 etree_value_type new;
139 new.section = abs_output_section;
145 exp_intop (bfd_vma value)
147 etree_type *new = stat_alloc (sizeof (new->value));
148 new->type.node_code = INT;
149 new->value.value = value;
150 new->value.str = NULL;
151 new->type.node_class = etree_value;
156 exp_bigintop (bfd_vma value, char *str)
158 etree_type *new = stat_alloc (sizeof (new->value));
159 new->type.node_code = INT;
160 new->value.value = value;
161 new->value.str = str;
162 new->type.node_class = etree_value;
166 /* Build an expression representing an unnamed relocatable value. */
169 exp_relop (asection *section, bfd_vma value)
171 etree_type *new = stat_alloc (sizeof (new->rel));
172 new->type.node_code = REL;
173 new->type.node_class = etree_rel;
174 new->rel.section = section;
175 new->rel.value = value;
179 static etree_value_type
180 new_rel (bfd_vma value,
182 lang_output_section_statement_type *section)
184 etree_value_type new;
188 new.section = section;
192 static etree_value_type
193 new_rel_from_section (bfd_vma value,
194 lang_output_section_statement_type *section)
196 etree_value_type new;
200 new.section = section;
202 new.value -= section->bfd_section->vma;
207 static etree_value_type
208 fold_unary (etree_type *tree,
209 lang_output_section_statement_type *current_section,
210 lang_phase_type allocation_done,
214 etree_value_type result;
216 result = exp_fold_tree (tree->unary.child,
218 allocation_done, dot, dotp);
221 switch (tree->type.node_code)
224 if (allocation_done != lang_first_phase_enum)
225 result = new_rel_from_section (align_n (dot, result.value),
228 result.valid_p = FALSE;
232 if (allocation_done != lang_first_phase_enum)
234 result.value += result.section->bfd_section->vma;
235 result.section = abs_output_section;
238 result.valid_p = FALSE;
243 result.value = ~result.value;
248 result.value = !result.value;
253 result.value = -result.value;
257 /* Return next place aligned to value. */
258 if (allocation_done == lang_allocating_phase_enum)
261 result.value = align_n (dot, result.value);
264 result.valid_p = FALSE;
267 case DATA_SEGMENT_END:
268 if (allocation_done != lang_first_phase_enum
269 && current_section == abs_output_section
270 && (exp_data_seg.phase == exp_dataseg_align_seen
271 || exp_data_seg.phase == exp_dataseg_adjust
272 || allocation_done != lang_allocating_phase_enum))
274 if (exp_data_seg.phase == exp_dataseg_align_seen)
276 exp_data_seg.phase = exp_dataseg_end_seen;
277 exp_data_seg.end = result.value;
281 result.valid_p = FALSE;
293 static etree_value_type
294 fold_binary (etree_type *tree,
295 lang_output_section_statement_type *current_section,
296 lang_phase_type allocation_done,
300 etree_value_type result;
302 result = exp_fold_tree (tree->binary.lhs, current_section,
303 allocation_done, dot, dotp);
306 etree_value_type other;
308 other = exp_fold_tree (tree->binary.rhs,
310 allocation_done, dot, dotp);
313 /* If the values are from different sections, or this is an
314 absolute expression, make both the source arguments
315 absolute. However, adding or subtracting an absolute
316 value from a relative value is meaningful, and is an
318 if (current_section != abs_output_section
319 && (other.section == abs_output_section
320 || (result.section == abs_output_section
321 && tree->type.node_code == '+'))
322 && (tree->type.node_code == '+'
323 || tree->type.node_code == '-'))
325 if (other.section != abs_output_section)
327 /* Keep the section of the other term. */
328 if (tree->type.node_code == '+')
329 other.value = result.value + other.value;
331 other.value = result.value - other.value;
335 else if (result.section != other.section
336 || current_section == abs_output_section)
342 switch (tree->type.node_code)
345 if (other.value == 0)
346 einfo (_("%F%S %% by zero\n"));
347 result.value = ((bfd_signed_vma) result.value
348 % (bfd_signed_vma) other.value);
352 if (other.value == 0)
353 einfo (_("%F%S / by zero\n"));
354 result.value = ((bfd_signed_vma) result.value
355 / (bfd_signed_vma) other.value);
358 #define BOP(x,y) case x : result.value = result.value y other.value; break;
377 if (result.value < other.value)
382 if (result.value > other.value)
387 result.value = align_n (result.value, other.value);
390 case DATA_SEGMENT_ALIGN:
391 if (allocation_done != lang_first_phase_enum
392 && current_section == abs_output_section
393 && (exp_data_seg.phase == exp_dataseg_none
394 || exp_data_seg.phase == exp_dataseg_adjust
395 || allocation_done != lang_allocating_phase_enum))
397 bfd_vma maxpage = result.value;
399 result.value = align_n (dot, maxpage);
400 if (exp_data_seg.phase != exp_dataseg_adjust)
402 result.value += dot & (maxpage - 1);
403 if (allocation_done == lang_allocating_phase_enum)
405 exp_data_seg.phase = exp_dataseg_align_seen;
406 exp_data_seg.base = result.value;
407 exp_data_seg.pagesize = other.value;
410 else if (other.value < maxpage)
411 result.value += (dot + other.value - 1)
412 & (maxpage - other.value);
415 result.valid_p = FALSE;
424 result.valid_p = FALSE;
431 static etree_value_type
432 fold_trinary (etree_type *tree,
433 lang_output_section_statement_type *current_section,
434 lang_phase_type allocation_done,
438 etree_value_type result;
440 result = exp_fold_tree (tree->trinary.cond, current_section,
441 allocation_done, dot, dotp);
443 result = exp_fold_tree ((result.value
445 : tree->trinary.rhs),
447 allocation_done, dot, dotp);
452 static etree_value_type
453 fold_name (etree_type *tree,
454 lang_output_section_statement_type *current_section,
455 lang_phase_type allocation_done,
458 etree_value_type result;
460 result.valid_p = FALSE;
462 switch (tree->type.node_code)
465 if (allocation_done != lang_first_phase_enum)
466 result = new_abs (bfd_sizeof_headers (output_bfd,
467 link_info.relocatable));
470 if (allocation_done == lang_first_phase_enum)
471 lang_track_definedness (tree->name.name);
474 struct bfd_link_hash_entry *h;
476 = lang_symbol_definition_iteration (tree->name.name);
478 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
481 result.value = (h != NULL
482 && (h->type == bfd_link_hash_defined
483 || h->type == bfd_link_hash_defweak
484 || h->type == bfd_link_hash_common)
485 && (def_iteration == lang_statement_iteration
486 || def_iteration == -1));
487 result.section = abs_output_section;
488 result.valid_p = TRUE;
492 if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
494 if (allocation_done != lang_first_phase_enum)
495 result = new_rel_from_section (dot, current_section);
497 else if (allocation_done != lang_first_phase_enum)
499 struct bfd_link_hash_entry *h;
501 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
505 einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
506 else if (h->type == bfd_link_hash_defined
507 || h->type == bfd_link_hash_defweak)
509 if (bfd_is_abs_section (h->u.def.section))
510 result = new_abs (h->u.def.value);
511 else if (allocation_done == lang_final_phase_enum
512 || allocation_done == lang_allocating_phase_enum)
514 asection *output_section;
516 output_section = h->u.def.section->output_section;
517 if (output_section == NULL)
518 einfo (_("%X%S: unresolvable symbol `%s' referenced in expression\n"),
522 lang_output_section_statement_type *os;
524 os = (lang_output_section_statement_lookup
525 (bfd_get_section_name (output_bfd,
528 /* FIXME: Is this correct if this section is
529 being linked with -R? */
530 result = new_rel ((h->u.def.value
531 + h->u.def.section->output_offset),
537 else if (allocation_done == lang_final_phase_enum)
538 einfo (_("%F%S: undefined symbol `%s' referenced in expression\n"),
540 else if (h->type == bfd_link_hash_new)
542 h->type = bfd_link_hash_undefined;
543 h->u.undef.abfd = NULL;
544 bfd_link_add_undef (link_info.hash, h);
550 if (allocation_done != lang_first_phase_enum)
552 lang_output_section_statement_type *os;
554 os = lang_output_section_find (tree->name.name);
555 if (os && os->processed > 0)
556 result = new_rel (0, NULL, os);
561 if (allocation_done != lang_first_phase_enum)
563 lang_output_section_statement_type *os;
565 os = lang_output_section_find (tree->name.name);
566 if (os && os->processed != 0)
568 if (os->load_base == NULL)
569 result = new_rel (0, NULL, os);
571 result = exp_fold_tree_no_dot (os->load_base,
579 if (allocation_done != lang_first_phase_enum)
581 int opb = bfd_octets_per_byte (output_bfd);
582 lang_output_section_statement_type *os;
584 os = lang_output_section_find (tree->name.name);
585 if (os && os->processed > 0)
586 result = new_abs (os->bfd_section->_raw_size / opb);
599 exp_fold_tree (etree_type *tree,
600 lang_output_section_statement_type *current_section,
601 lang_phase_type allocation_done,
605 etree_value_type result;
609 result.valid_p = FALSE;
613 switch (tree->type.node_class)
616 result = new_rel (tree->value.value, tree->value.str, current_section);
620 if (allocation_done != lang_final_phase_enum)
621 result.valid_p = FALSE;
623 result = new_rel ((tree->rel.value
624 + tree->rel.section->output_section->vma
625 + tree->rel.section->output_offset),
631 result = exp_fold_tree (tree->assert_s.child,
633 allocation_done, dot, dotp);
637 einfo ("%F%P: %s\n", tree->assert_s.message);
643 result = fold_unary (tree, current_section, allocation_done,
648 result = fold_binary (tree, current_section, allocation_done,
653 result = fold_trinary (tree, current_section, allocation_done,
660 if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
662 /* Assignment to dot can only be done during allocation. */
663 if (tree->type.node_class != etree_assign)
664 einfo (_("%F%S can not PROVIDE assignment to location counter\n"));
665 if (allocation_done == lang_allocating_phase_enum
666 || (allocation_done == lang_final_phase_enum
667 && current_section == abs_output_section))
669 result = exp_fold_tree (tree->assign.src,
671 allocation_done, dot,
673 if (! result.valid_p)
674 einfo (_("%F%S invalid assignment to location counter\n"));
677 if (current_section == NULL)
678 einfo (_("%F%S assignment to location counter invalid outside of SECTION\n"));
683 nextdot = (result.value
684 + current_section->bfd_section->vma);
686 && current_section != abs_output_section)
687 einfo (_("%F%S cannot move location counter backwards (from %V to %V)\n"),
697 result = exp_fold_tree (tree->assign.src,
698 current_section, allocation_done,
703 struct bfd_link_hash_entry *h;
705 if (tree->type.node_class == etree_assign)
709 h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
710 create, FALSE, TRUE);
714 einfo (_("%P%F:%s: hash creation failed\n"),
717 else if (tree->type.node_class == etree_provide
718 && h->type != bfd_link_hash_new
719 && h->type != bfd_link_hash_undefined
720 && h->type != bfd_link_hash_common)
722 /* Do nothing. The symbol was defined by some
727 /* FIXME: Should we worry if the symbol is already
729 lang_update_definedness (tree->assign.dst, h);
730 h->type = bfd_link_hash_defined;
731 h->u.def.value = result.value;
732 h->u.def.section = result.section->bfd_section;
733 if (tree->type.node_class == etree_provide)
734 tree->type.node_class = etree_provided;
741 result = fold_name (tree, current_section, allocation_done, dot);
752 static etree_value_type
753 exp_fold_tree_no_dot (etree_type *tree,
754 lang_output_section_statement_type *current_section,
755 lang_phase_type allocation_done)
757 return exp_fold_tree (tree, current_section, allocation_done, 0, NULL);
761 exp_binop (int code, etree_type *lhs, etree_type *rhs)
763 etree_type value, *new;
766 value.type.node_code = code;
767 value.binary.lhs = lhs;
768 value.binary.rhs = rhs;
769 value.type.node_class = etree_binary;
770 r = exp_fold_tree_no_dot (&value,
772 lang_first_phase_enum);
775 return exp_intop (r.value);
777 new = stat_alloc (sizeof (new->binary));
778 memcpy (new, &value, sizeof (new->binary));
783 exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
785 etree_type value, *new;
787 value.type.node_code = code;
788 value.trinary.lhs = lhs;
789 value.trinary.cond = cond;
790 value.trinary.rhs = rhs;
791 value.type.node_class = etree_trinary;
792 r = exp_fold_tree_no_dot (&value, NULL, lang_first_phase_enum);
794 return exp_intop (r.value);
796 new = stat_alloc (sizeof (new->trinary));
797 memcpy (new, &value, sizeof (new->trinary));
802 exp_unop (int code, etree_type *child)
804 etree_type value, *new;
807 value.unary.type.node_code = code;
808 value.unary.child = child;
809 value.unary.type.node_class = etree_unary;
810 r = exp_fold_tree_no_dot (&value, abs_output_section,
811 lang_first_phase_enum);
813 return exp_intop (r.value);
815 new = stat_alloc (sizeof (new->unary));
816 memcpy (new, &value, sizeof (new->unary));
821 exp_nameop (int code, const char *name)
823 etree_type value, *new;
825 value.name.type.node_code = code;
826 value.name.name = name;
827 value.name.type.node_class = etree_name;
829 r = exp_fold_tree_no_dot (&value, NULL, lang_first_phase_enum);
831 return exp_intop (r.value);
833 new = stat_alloc (sizeof (new->name));
834 memcpy (new, &value, sizeof (new->name));
840 exp_assop (int code, const char *dst, etree_type *src)
842 etree_type value, *new;
844 value.assign.type.node_code = code;
846 value.assign.src = src;
847 value.assign.dst = dst;
848 value.assign.type.node_class = etree_assign;
851 if (exp_fold_tree_no_dot (&value, &result))
852 return exp_intop (result);
854 new = stat_alloc (sizeof (new->assign));
855 memcpy (new, &value, sizeof (new->assign));
859 /* Handle PROVIDE. */
862 exp_provide (const char *dst, etree_type *src)
866 n = stat_alloc (sizeof (n->assign));
867 n->assign.type.node_code = '=';
868 n->assign.type.node_class = etree_provide;
877 exp_assert (etree_type *exp, const char *message)
881 n = stat_alloc (sizeof (n->assert_s));
882 n->assert_s.type.node_code = '!';
883 n->assert_s.type.node_class = etree_assert;
884 n->assert_s.child = exp;
885 n->assert_s.message = message;
890 exp_print_tree (etree_type *tree)
892 if (config.map_file == NULL)
893 config.map_file = stderr;
897 minfo ("NULL TREE\n");
901 switch (tree->type.node_class)
904 minfo ("0x%v", tree->value.value);
907 if (tree->rel.section->owner != NULL)
908 minfo ("%B:", tree->rel.section->owner);
909 minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
913 if (tree->assign.dst->sdefs != NULL)
914 fprintf (config.map_file, "%s (%x) ", tree->assign.dst->name,
915 tree->assign.dst->sdefs->value);
917 fprintf (config.map_file, "%s (UNDEFINED)", tree->assign.dst->name);
919 fprintf (config.map_file, "%s", tree->assign.dst);
920 exp_print_token (tree->type.node_code, TRUE);
921 exp_print_tree (tree->assign.src);
925 fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
926 exp_print_tree (tree->assign.src);
927 fprintf (config.map_file, ")");
930 fprintf (config.map_file, "(");
931 exp_print_tree (tree->binary.lhs);
932 exp_print_token (tree->type.node_code, TRUE);
933 exp_print_tree (tree->binary.rhs);
934 fprintf (config.map_file, ")");
937 exp_print_tree (tree->trinary.cond);
938 fprintf (config.map_file, "?");
939 exp_print_tree (tree->trinary.lhs);
940 fprintf (config.map_file, ":");
941 exp_print_tree (tree->trinary.rhs);
944 exp_print_token (tree->unary.type.node_code, FALSE);
945 if (tree->unary.child)
947 fprintf (config.map_file, " (");
948 exp_print_tree (tree->unary.child);
949 fprintf (config.map_file, ")");
954 fprintf (config.map_file, "ASSERT (");
955 exp_print_tree (tree->assert_s.child);
956 fprintf (config.map_file, ", %s)", tree->assert_s.message);
960 fprintf (config.map_file, "????????");
963 if (tree->type.node_code == NAME)
965 fprintf (config.map_file, "%s", tree->name.name);
969 exp_print_token (tree->type.node_code, FALSE);
971 fprintf (config.map_file, " (%s)", tree->name.name);
981 exp_get_vma (etree_type *tree,
984 lang_phase_type allocation_done)
990 r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
991 if (! r.valid_p && name != NULL)
992 einfo (_("%F%S nonconstant expression for %s\n"), name);
1000 exp_get_value_int (etree_type *tree,
1003 lang_phase_type allocation_done)
1005 return exp_get_vma (tree, def, name, allocation_done);
1009 exp_get_fill (etree_type *tree,
1012 lang_phase_type allocation_done)
1022 r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
1023 if (! r.valid_p && name != NULL)
1024 einfo (_("%F%S nonconstant expression for %s\n"), name);
1026 if (r.str != NULL && (len = strlen (r.str)) != 0)
1030 fill = xmalloc ((len + 1) / 2 + sizeof (*fill) - 1);
1031 fill->size = (len + 1) / 2;
1041 digit = (digit - 'A' + '0' + 10) & 0xf;
1055 fill = xmalloc (4 + sizeof (*fill) - 1);
1057 fill->data[0] = (val >> 24) & 0xff;
1058 fill->data[1] = (val >> 16) & 0xff;
1059 fill->data[2] = (val >> 8) & 0xff;
1060 fill->data[3] = (val >> 0) & 0xff;
1067 exp_get_abs_int (etree_type *tree,
1068 int def ATTRIBUTE_UNUSED,
1070 lang_phase_type allocation_done)
1072 etree_value_type res;
1073 res = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
1076 res.value += res.section->bfd_section->vma;
1078 einfo (_("%F%S non constant expression for %s\n"), name);
1084 align_n (bfd_vma value, bfd_vma align)
1089 value = (value + align - 1) / align;
1090 return value * align;