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
42 static void exp_print_token PARAMS ((token_code_type code));
43 static void make_abs PARAMS ((etree_value_type *ptr));
44 static etree_value_type new_abs PARAMS ((bfd_vma value));
45 static void check PARAMS ((lang_output_section_statement_type *os,
46 const char *name, const char *op));
47 static etree_value_type new_rel
48 PARAMS ((bfd_vma value, lang_output_section_statement_type *section));
49 static etree_value_type new_rel_from_section
50 PARAMS ((bfd_vma value, lang_output_section_statement_type *section));
51 static etree_value_type fold_binary
52 PARAMS ((etree_type *tree,
53 lang_output_section_statement_type *current_section,
54 lang_phase_type allocation_done,
55 bfd_vma dot, bfd_vma *dotp));
56 static etree_value_type fold_name
57 PARAMS ((etree_type *tree,
58 lang_output_section_statement_type *current_section,
59 lang_phase_type allocation_done,
61 static etree_value_type exp_fold_tree_no_dot
62 PARAMS ((etree_type *tree,
63 lang_output_section_statement_type *current_section,
64 lang_phase_type allocation_done));
67 exp_print_token (code)
75 { REL, "relocateable" },
95 { SECTIONS, "SECTIONS" },
96 { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
100 { LOADADDR, "LOADADDR" },
101 { MEMORY, "MEMORY" },
102 { DEFINED, "DEFINED" },
103 { TARGET_K, "TARGET" },
104 { SEARCH_DIR, "SEARCH_DIR" },
116 for (idx = 0; table[idx].name != (char *) NULL; idx++)
118 if (table[idx].code == code)
120 fprintf (config.map_file, "%s", table[idx].name);
124 /* Not in table, just print it alone */
125 fprintf (config.map_file, "%c", code);
130 etree_value_type *ptr;
132 asection *s = ptr->section->bfd_section;
133 ptr->value += s->vma;
134 ptr->section = abs_output_section;
137 static etree_value_type
141 etree_value_type new;
143 new.section = abs_output_section;
150 lang_output_section_statement_type *os;
155 einfo (_("%F%P: %s uses undefined section %s\n"), op, name);
157 einfo (_("%F%P: %s forward reference of section %s\n"), op, name);
164 etree_type *new = (etree_type *) stat_alloc (sizeof (new->value));
165 new->type.node_code = INT;
166 new->value.value = value;
167 new->type.node_class = etree_value;
172 /* Build an expression representing an unnamed relocateable value. */
175 exp_relop (section, value)
179 etree_type *new = (etree_type *) stat_alloc (sizeof (new->rel));
180 new->type.node_code = REL;
181 new->type.node_class = etree_rel;
182 new->rel.section = section;
183 new->rel.value = value;
187 static etree_value_type
188 new_rel (value, section)
190 lang_output_section_statement_type *section;
192 etree_value_type new;
195 new.section = section;
199 static etree_value_type
200 new_rel_from_section (value, section)
202 lang_output_section_statement_type *section;
204 etree_value_type new;
207 new.section = section;
209 new.value -= section->bfd_section->vma;
214 static etree_value_type
215 fold_binary (tree, current_section, allocation_done, dot, dotp)
217 lang_output_section_statement_type *current_section;
218 lang_phase_type allocation_done;
222 etree_value_type result;
224 result = exp_fold_tree (tree->binary.lhs, current_section,
225 allocation_done, dot, dotp);
228 etree_value_type other;
230 other = exp_fold_tree (tree->binary.rhs,
232 allocation_done, dot, dotp);
235 /* If the values are from different sections, or this is an
236 absolute expression, make both the source arguments
237 absolute. However, adding or subtracting an absolute
238 value from a relative value is meaningful, and is an
240 if (current_section != abs_output_section
241 && (other.section == abs_output_section
242 || (result.section == abs_output_section
243 && tree->type.node_code == '+'))
244 && (tree->type.node_code == '+'
245 || tree->type.node_code == '-'))
247 etree_value_type hold;
249 /* If there is only one absolute term, make sure it is the
251 if (other.section != abs_output_section)
258 else if (result.section != other.section
259 || current_section == abs_output_section)
265 switch (tree->type.node_code)
268 if (other.value == 0)
269 einfo (_("%F%S %% by zero\n"));
270 result.value = ((bfd_signed_vma) result.value
271 % (bfd_signed_vma) other.value);
275 if (other.value == 0)
276 einfo (_("%F%S / by zero\n"));
277 result.value = ((bfd_signed_vma) result.value
278 / (bfd_signed_vma) other.value);
281 #define BOP(x,y) case x : result.value = result.value y other.value; break;
300 if (result.value < other.value)
305 if (result.value > other.value)
315 result.valid_p = false;
325 etree_value_type new;
330 static etree_value_type
331 fold_name (tree, current_section, allocation_done, dot)
333 lang_output_section_statement_type *current_section;
334 lang_phase_type allocation_done;
337 etree_value_type result;
338 switch (tree->type.node_code)
341 if (allocation_done != lang_first_phase_enum)
343 result = new_abs ((bfd_vma)
344 bfd_sizeof_headers (output_bfd,
345 link_info.relocateable));
349 result.valid_p = false;
353 if (allocation_done == lang_first_phase_enum)
354 result.valid_p = false;
357 struct bfd_link_hash_entry *h;
359 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
362 result.value = (h != (struct bfd_link_hash_entry *) NULL
363 && (h->type == bfd_link_hash_defined
364 || h->type == bfd_link_hash_defweak
365 || h->type == bfd_link_hash_common));
367 result.valid_p = true;
371 result.valid_p = false;
372 if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
374 if (allocation_done != lang_first_phase_enum)
375 result = new_rel_from_section (dot, current_section);
379 else if (allocation_done != lang_first_phase_enum)
381 struct bfd_link_hash_entry *h;
383 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
387 && (h->type == bfd_link_hash_defined
388 || h->type == bfd_link_hash_defweak))
390 if (bfd_is_abs_section (h->u.def.section))
391 result = new_abs (h->u.def.value);
392 else if (allocation_done == lang_final_phase_enum
393 || allocation_done == lang_allocating_phase_enum)
395 asection *output_section;
397 output_section = h->u.def.section->output_section;
398 if (output_section == NULL)
399 einfo (_("%X%S: unresolvable symbol `%s' referenced in expression\n"),
403 lang_output_section_statement_type *os;
405 os = (lang_output_section_statement_lookup
406 (bfd_get_section_name (output_bfd,
409 /* FIXME: Is this correct if this section is
410 being linked with -R? */
411 result = new_rel ((h->u.def.value
412 + h->u.def.section->output_offset),
417 else if (allocation_done == lang_final_phase_enum)
418 einfo (_("%F%S: undefined symbol `%s' referenced in expression\n"),
424 if (allocation_done != lang_first_phase_enum)
426 lang_output_section_statement_type *os;
428 os = lang_output_section_find (tree->name.name);
429 check (os, tree->name.name, "ADDR");
430 result = new_rel (0, os);
437 if (allocation_done != lang_first_phase_enum)
439 lang_output_section_statement_type *os;
441 os = lang_output_section_find (tree->name.name);
442 check (os, tree->name.name, "LOADADDR");
443 if (os->load_base == NULL)
444 result = new_rel (0, os);
446 result = exp_fold_tree_no_dot (os->load_base,
455 if (allocation_done != lang_first_phase_enum)
457 int opb = bfd_octets_per_byte (output_bfd);
458 lang_output_section_statement_type *os;
460 os = lang_output_section_find (tree->name.name);
461 check (os, tree->name.name, "SIZEOF");
462 result = new_abs (os->bfd_section->_raw_size / opb);
477 exp_fold_tree (tree, current_section, allocation_done, dot, dotp)
479 lang_output_section_statement_type *current_section;
480 lang_phase_type allocation_done;
484 etree_value_type result;
488 result.valid_p = false;
492 switch (tree->type.node_class)
495 result = new_rel (tree->value.value, current_section);
499 if (allocation_done != lang_final_phase_enum)
500 result.valid_p = false;
502 result = new_rel ((tree->rel.value
503 + tree->rel.section->output_section->vma
504 + tree->rel.section->output_offset),
509 result = exp_fold_tree (tree->assert_s.child,
511 allocation_done, dot, dotp);
515 einfo ("%F%P: %s\n", tree->assert_s.message);
521 result = exp_fold_tree (tree->unary.child,
523 allocation_done, dot, dotp);
526 switch (tree->type.node_code)
529 if (allocation_done != lang_first_phase_enum)
530 result = new_rel_from_section (ALIGN_N (dot, result.value),
533 result.valid_p = false;
537 if (allocation_done != lang_first_phase_enum && result.valid_p)
539 result.value += result.section->bfd_section->vma;
540 result.section = abs_output_section;
543 result.valid_p = false;
548 result.value = ~result.value;
553 result.value = !result.value;
558 result.value = -result.value;
562 /* Return next place aligned to value. */
563 if (allocation_done == lang_allocating_phase_enum)
566 result.value = ALIGN_N (dot, result.value);
569 result.valid_p = false;
580 result = exp_fold_tree (tree->trinary.cond, current_section,
581 allocation_done, dot, dotp);
583 result = exp_fold_tree ((result.value
585 : tree->trinary.rhs),
587 allocation_done, dot, dotp);
591 result = fold_binary (tree, current_section, allocation_done,
598 if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
600 /* Assignment to dot can only be done during allocation */
601 if (tree->type.node_class != etree_assign)
602 einfo (_("%F%S can not PROVIDE assignment to location counter\n"));
603 if (allocation_done == lang_allocating_phase_enum
604 || (allocation_done == lang_final_phase_enum
605 && current_section == abs_output_section))
607 result = exp_fold_tree (tree->assign.src,
609 lang_allocating_phase_enum, dot,
611 if (! result.valid_p)
612 einfo (_("%F%S invalid assignment to location counter\n"));
615 if (current_section == NULL)
616 einfo (_("%F%S assignment to location counter invalid outside of SECTION\n"));
621 nextdot = (result.value
622 + current_section->bfd_section->vma);
624 && current_section != abs_output_section)
626 einfo (_("%F%S cannot move location counter backwards (from %V to %V)\n"),
637 result = exp_fold_tree (tree->assign.src,
638 current_section, allocation_done,
643 struct bfd_link_hash_entry *h;
645 if (tree->type.node_class == etree_assign)
649 h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
650 create, false, false);
651 if (h == (struct bfd_link_hash_entry *) NULL)
653 if (tree->type.node_class == etree_assign)
654 einfo (_("%P%F:%s: hash creation failed\n"),
657 else if (tree->type.node_class == etree_provide
658 && h->type != bfd_link_hash_undefined
659 && h->type != bfd_link_hash_common)
661 /* Do nothing. The symbol was defined by some
666 /* FIXME: Should we worry if the symbol is already
668 h->type = bfd_link_hash_defined;
669 h->u.def.value = result.value;
670 h->u.def.section = result.section->bfd_section;
671 if (tree->type.node_class == etree_provide)
672 tree->type.node_class = etree_provided;
679 result = fold_name (tree, current_section, allocation_done, dot);
690 static etree_value_type
691 exp_fold_tree_no_dot (tree, current_section, allocation_done)
693 lang_output_section_statement_type *current_section;
694 lang_phase_type allocation_done;
696 return exp_fold_tree (tree, current_section, allocation_done,
697 (bfd_vma) 0, (bfd_vma *) NULL);
701 exp_binop (code, lhs, rhs)
706 etree_type value, *new;
709 value.type.node_code = code;
710 value.binary.lhs = lhs;
711 value.binary.rhs = rhs;
712 value.type.node_class = etree_binary;
713 r = exp_fold_tree_no_dot (&value,
715 lang_first_phase_enum);
718 return exp_intop (r.value);
720 new = (etree_type *) stat_alloc (sizeof (new->binary));
721 memcpy ((char *) new, (char *) &value, sizeof (new->binary));
726 exp_trinop (code, cond, lhs, rhs)
732 etree_type value, *new;
734 value.type.node_code = code;
735 value.trinary.lhs = lhs;
736 value.trinary.cond = cond;
737 value.trinary.rhs = rhs;
738 value.type.node_class = etree_trinary;
739 r = exp_fold_tree_no_dot (&value,
740 (lang_output_section_statement_type *) NULL,
741 lang_first_phase_enum);
744 return exp_intop (r.value);
746 new = (etree_type *) stat_alloc (sizeof (new->trinary));
747 memcpy ((char *) new, (char *) &value, sizeof (new->trinary));
752 exp_unop (code, child)
756 etree_type value, *new;
759 value.unary.type.node_code = code;
760 value.unary.child = child;
761 value.unary.type.node_class = etree_unary;
762 r = exp_fold_tree_no_dot (&value, abs_output_section,
763 lang_first_phase_enum);
766 return exp_intop (r.value);
768 new = (etree_type *) stat_alloc (sizeof (new->unary));
769 memcpy ((char *) new, (char *) &value, sizeof (new->unary));
774 exp_nameop (code, name)
778 etree_type value, *new;
780 value.name.type.node_code = code;
781 value.name.name = name;
782 value.name.type.node_class = etree_name;
784 r = exp_fold_tree_no_dot (&value,
785 (lang_output_section_statement_type *) NULL,
786 lang_first_phase_enum);
789 return exp_intop (r.value);
791 new = (etree_type *) stat_alloc (sizeof (new->name));
792 memcpy ((char *) new, (char *) &value, sizeof (new->name));
798 exp_assop (code, dst, src)
803 etree_type value, *new;
805 value.assign.type.node_code = code;
807 value.assign.src = src;
808 value.assign.dst = dst;
809 value.assign.type.node_class = etree_assign;
812 if (exp_fold_tree_no_dot (&value, &result))
814 return exp_intop (result);
817 new = (etree_type *) stat_alloc (sizeof (new->assign));
818 memcpy ((char *) new, (char *) &value, sizeof (new->assign));
822 /* Handle PROVIDE. */
825 exp_provide (dst, src)
831 n = (etree_type *) stat_alloc (sizeof (n->assign));
832 n->assign.type.node_code = '=';
833 n->assign.type.node_class = etree_provide;
842 exp_assert (exp, message)
848 n = (etree_type *) stat_alloc (sizeof (n->assert_s));
849 n->assert_s.type.node_code = '!';
850 n->assert_s.type.node_class = etree_assert;
851 n->assert_s.child = exp;
852 n->assert_s.message = message;
857 exp_print_tree (tree)
860 switch (tree->type.node_class)
863 minfo ("0x%v", tree->value.value);
866 if (tree->rel.section->owner != NULL)
867 minfo ("%B:", tree->rel.section->owner);
868 minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
872 if (tree->assign.dst->sdefs != (asymbol *) NULL)
874 fprintf (config.map_file, "%s (%x) ", tree->assign.dst->name,
875 tree->assign.dst->sdefs->value);
879 fprintf (config.map_file, "%s (UNDEFINED)", tree->assign.dst->name);
882 fprintf (config.map_file, "%s", tree->assign.dst);
883 exp_print_token (tree->type.node_code);
884 exp_print_tree (tree->assign.src);
888 fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
889 exp_print_tree (tree->assign.src);
890 fprintf (config.map_file, ")");
893 fprintf (config.map_file, "(");
894 exp_print_tree (tree->binary.lhs);
895 exp_print_token (tree->type.node_code);
896 exp_print_tree (tree->binary.rhs);
897 fprintf (config.map_file, ")");
900 exp_print_tree (tree->trinary.cond);
901 fprintf (config.map_file, "?");
902 exp_print_tree (tree->trinary.lhs);
903 fprintf (config.map_file, ":");
904 exp_print_tree (tree->trinary.rhs);
907 exp_print_token (tree->unary.type.node_code);
908 if (tree->unary.child)
910 fprintf (config.map_file, "(");
911 exp_print_tree (tree->unary.child);
912 fprintf (config.map_file, ")");
917 fprintf (config.map_file, "ASSERT (");
918 exp_print_tree (tree->assert_s.child);
919 fprintf (config.map_file, ", %s)", tree->assert_s.message);
923 fprintf (config.map_file, "????????");
926 if (tree->type.node_code == NAME)
928 fprintf (config.map_file, "%s", tree->name.name);
932 exp_print_token (tree->type.node_code);
934 fprintf (config.map_file, "(%s)", tree->name.name);
944 exp_get_vma (tree, def, name, allocation_done)
948 lang_phase_type allocation_done;
954 r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
955 if (! r.valid_p && name != NULL)
956 einfo (_("%F%S nonconstant expression for %s\n"), name);
964 exp_get_value_int (tree, def, name, allocation_done)
968 lang_phase_type allocation_done;
970 return (int) exp_get_vma (tree, (bfd_vma) def, name, allocation_done);
974 exp_get_abs_int (tree, def, name, allocation_done)
976 int def ATTRIBUTE_UNUSED;
978 lang_phase_type allocation_done;
980 etree_value_type res;
981 res = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
985 res.value += res.section->bfd_section->vma;
989 einfo (_("%F%S non constant expression for %s\n"), name);