1 /* This module handles expression trees.
2 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 Free Software Foundation, Inc.
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 segment_type *segments;
53 /* Print the string representation of the given token. Surround it
54 with spaces if INFIX_P is TRUE. */
57 exp_print_token (token_code_type code, int infix_p)
91 { SECTIONS, "SECTIONS" },
92 { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
94 { DEFINED, "DEFINED" },
95 { TARGET_K, "TARGET" },
96 { SEARCH_DIR, "SEARCH_DIR" },
100 { SIZEOF, "SIZEOF" },
102 { LOADADDR, "LOADADDR" },
104 { REL, "relocatable" },
105 { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
106 { DATA_SEGMENT_RELRO_END, "DATA_SEGMENT_RELRO_END" },
107 { DATA_SEGMENT_END, "DATA_SEGMENT_END" },
108 { ORIGIN, "ORIGIN" },
109 { LENGTH, "LENGTH" },
110 { SEGMENT_START, "SEGMENT_START" }
114 for (idx = 0; idx < ARRAY_SIZE (table); idx++)
115 if (table[idx].code == code)
119 fputc (' ', config.map_file);
121 if (idx < ARRAY_SIZE (table))
122 fputs (table[idx].name, config.map_file);
124 fputc (code, config.map_file);
126 fprintf (config.map_file, "<code %d>", code);
129 fputc (' ', config.map_file);
133 make_abs (etree_value_type *ptr)
135 asection *s = ptr->section->bfd_section;
136 ptr->value += s->vma;
137 ptr->section = abs_output_section;
140 static etree_value_type
141 new_abs (bfd_vma value)
143 etree_value_type new;
145 new.section = abs_output_section;
151 exp_intop (bfd_vma value)
153 etree_type *new = stat_alloc (sizeof (new->value));
154 new->type.node_code = INT;
155 new->value.value = value;
156 new->value.str = NULL;
157 new->type.node_class = etree_value;
162 exp_bigintop (bfd_vma value, char *str)
164 etree_type *new = stat_alloc (sizeof (new->value));
165 new->type.node_code = INT;
166 new->value.value = value;
167 new->value.str = str;
168 new->type.node_class = etree_value;
172 /* Build an expression representing an unnamed relocatable value. */
175 exp_relop (asection *section, bfd_vma value)
177 etree_type *new = stat_alloc (sizeof (new->rel));
178 new->type.node_code = REL;
179 new->type.node_class = etree_rel;
180 new->rel.section = section;
181 new->rel.value = value;
185 static etree_value_type
186 new_rel (bfd_vma value,
188 lang_output_section_statement_type *section)
190 etree_value_type new;
194 new.section = section;
198 static etree_value_type
199 new_rel_from_section (bfd_vma value,
200 lang_output_section_statement_type *section)
202 etree_value_type new;
206 new.section = section;
208 new.value -= section->bfd_section->vma;
213 static etree_value_type
214 fold_unary (etree_type *tree,
215 lang_output_section_statement_type *current_section,
216 lang_phase_type allocation_done,
220 etree_value_type result;
222 result = exp_fold_tree (tree->unary.child,
224 allocation_done, dot, dotp);
227 switch (tree->type.node_code)
230 if (allocation_done != lang_first_phase_enum)
231 result = new_rel_from_section (align_n (dot, result.value),
234 result.valid_p = FALSE;
238 if (allocation_done != lang_first_phase_enum)
240 result.value += result.section->bfd_section->vma;
241 result.section = abs_output_section;
244 result.valid_p = FALSE;
249 result.value = ~result.value;
254 result.value = !result.value;
259 result.value = -result.value;
263 /* Return next place aligned to value. */
264 if (allocation_done == lang_allocating_phase_enum)
267 result.value = align_n (dot, result.value);
270 result.valid_p = FALSE;
273 case DATA_SEGMENT_END:
274 if (allocation_done != lang_first_phase_enum
275 && current_section == abs_output_section
276 && (exp_data_seg.phase == exp_dataseg_align_seen
277 || exp_data_seg.phase == exp_dataseg_relro_seen
278 || exp_data_seg.phase == exp_dataseg_adjust
279 || exp_data_seg.phase == exp_dataseg_relro_adjust
280 || allocation_done != lang_allocating_phase_enum))
282 if (exp_data_seg.phase == exp_dataseg_align_seen
283 || exp_data_seg.phase == exp_dataseg_relro_seen)
285 exp_data_seg.phase = exp_dataseg_end_seen;
286 exp_data_seg.end = result.value;
290 result.valid_p = FALSE;
302 static etree_value_type
303 fold_binary (etree_type *tree,
304 lang_output_section_statement_type *current_section,
305 lang_phase_type allocation_done,
309 etree_value_type result;
311 result = exp_fold_tree (tree->binary.lhs, current_section,
312 allocation_done, dot, dotp);
314 /* The SEGMENT_START operator is special because its first
315 operand is a string, not the name of a symbol. */
316 if (result.valid_p && tree->type.node_code == SEGMENT_START)
318 const char *segment_name;
320 /* Check to see if the user has overridden the default
322 segment_name = tree->binary.rhs->name.name;
323 for (seg = segments; seg; seg = seg->next)
324 if (strcmp (seg->name, segment_name) == 0)
327 result.value = seg->value;
329 result.section = NULL;
333 else if (result.valid_p)
335 etree_value_type other;
337 other = exp_fold_tree (tree->binary.rhs,
339 allocation_done, dot, dotp);
342 /* If the values are from different sections, or this is an
343 absolute expression, make both the source arguments
344 absolute. However, adding or subtracting an absolute
345 value from a relative value is meaningful, and is an
347 if (current_section != abs_output_section
348 && (other.section == abs_output_section
349 || (result.section == abs_output_section
350 && tree->type.node_code == '+'))
351 && (tree->type.node_code == '+'
352 || tree->type.node_code == '-'))
354 if (other.section != abs_output_section)
356 /* Keep the section of the other term. */
357 if (tree->type.node_code == '+')
358 other.value = result.value + other.value;
360 other.value = result.value - other.value;
364 else if (result.section != other.section
365 || current_section == abs_output_section)
371 switch (tree->type.node_code)
374 if (other.value == 0)
375 einfo (_("%F%S %% by zero\n"));
376 result.value = ((bfd_signed_vma) result.value
377 % (bfd_signed_vma) other.value);
381 if (other.value == 0)
382 einfo (_("%F%S / by zero\n"));
383 result.value = ((bfd_signed_vma) result.value
384 / (bfd_signed_vma) other.value);
387 #define BOP(x,y) case x : result.value = result.value y other.value; break;
406 if (result.value < other.value)
411 if (result.value > other.value)
416 result.value = align_n (result.value, other.value);
419 case DATA_SEGMENT_ALIGN:
420 if (allocation_done != lang_first_phase_enum
421 && current_section == abs_output_section
422 && (exp_data_seg.phase == exp_dataseg_none
423 || exp_data_seg.phase == exp_dataseg_adjust
424 || exp_data_seg.phase == exp_dataseg_relro_adjust
425 || allocation_done != lang_allocating_phase_enum))
427 bfd_vma maxpage = result.value;
429 result.value = align_n (dot, maxpage);
430 if (exp_data_seg.phase == exp_dataseg_relro_adjust)
431 result.value = exp_data_seg.base;
432 else if (exp_data_seg.phase != exp_dataseg_adjust)
434 result.value += dot & (maxpage - 1);
435 if (allocation_done == lang_allocating_phase_enum)
437 exp_data_seg.phase = exp_dataseg_align_seen;
438 exp_data_seg.min_base = align_n (dot, maxpage);
439 exp_data_seg.base = result.value;
440 exp_data_seg.pagesize = other.value;
441 exp_data_seg.maxpagesize = maxpage;
442 exp_data_seg.relro_end = 0;
445 else if (other.value < maxpage)
446 result.value += (dot + other.value - 1)
447 & (maxpage - other.value);
450 result.valid_p = FALSE;
453 case DATA_SEGMENT_RELRO_END:
454 if (allocation_done != lang_first_phase_enum
455 && (exp_data_seg.phase == exp_dataseg_align_seen
456 || exp_data_seg.phase == exp_dataseg_adjust
457 || exp_data_seg.phase == exp_dataseg_relro_adjust
458 || allocation_done != lang_allocating_phase_enum))
460 if (exp_data_seg.phase == exp_dataseg_align_seen
461 || exp_data_seg.phase == exp_dataseg_relro_adjust)
462 exp_data_seg.relro_end
463 = result.value + other.value;
464 if (exp_data_seg.phase == exp_dataseg_relro_adjust
465 && (exp_data_seg.relro_end
466 & (exp_data_seg.pagesize - 1)))
468 exp_data_seg.relro_end += exp_data_seg.pagesize - 1;
469 exp_data_seg.relro_end &= ~(exp_data_seg.pagesize - 1);
470 result.value = exp_data_seg.relro_end - other.value;
472 if (exp_data_seg.phase == exp_dataseg_align_seen)
473 exp_data_seg.phase = exp_dataseg_relro_seen;
476 result.valid_p = FALSE;
485 result.valid_p = FALSE;
492 static etree_value_type
493 fold_trinary (etree_type *tree,
494 lang_output_section_statement_type *current_section,
495 lang_phase_type allocation_done,
499 etree_value_type result;
501 result = exp_fold_tree (tree->trinary.cond, current_section,
502 allocation_done, dot, dotp);
504 result = exp_fold_tree ((result.value
506 : tree->trinary.rhs),
508 allocation_done, dot, dotp);
513 static etree_value_type
514 fold_name (etree_type *tree,
515 lang_output_section_statement_type *current_section,
516 lang_phase_type allocation_done,
519 etree_value_type result;
521 result.valid_p = FALSE;
523 switch (tree->type.node_code)
526 if (allocation_done != lang_first_phase_enum)
527 result = new_abs (bfd_sizeof_headers (output_bfd,
528 link_info.relocatable));
531 if (allocation_done == lang_first_phase_enum)
532 lang_track_definedness (tree->name.name);
535 struct bfd_link_hash_entry *h;
537 = lang_symbol_definition_iteration (tree->name.name);
539 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
542 result.value = (h != NULL
543 && (h->type == bfd_link_hash_defined
544 || h->type == bfd_link_hash_defweak
545 || h->type == bfd_link_hash_common)
546 && (def_iteration == lang_statement_iteration
547 || def_iteration == -1));
548 result.section = abs_output_section;
549 result.valid_p = TRUE;
553 if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
555 if (allocation_done != lang_first_phase_enum)
556 result = new_rel_from_section (dot, current_section);
558 else if (allocation_done != lang_first_phase_enum)
560 struct bfd_link_hash_entry *h;
562 h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
566 einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
567 else if (h->type == bfd_link_hash_defined
568 || h->type == bfd_link_hash_defweak)
570 if (bfd_is_abs_section (h->u.def.section))
571 result = new_abs (h->u.def.value);
572 else if (allocation_done == lang_final_phase_enum
573 || allocation_done == lang_allocating_phase_enum)
575 asection *output_section;
577 output_section = h->u.def.section->output_section;
578 if (output_section == NULL)
579 einfo (_("%X%S: unresolvable symbol `%s' referenced in expression\n"),
583 lang_output_section_statement_type *os;
585 os = (lang_output_section_statement_lookup
586 (bfd_get_section_name (output_bfd,
589 /* FIXME: Is this correct if this section is
590 being linked with -R? */
591 result = new_rel ((h->u.def.value
592 + h->u.def.section->output_offset),
598 else if (allocation_done == lang_final_phase_enum)
599 einfo (_("%F%S: undefined symbol `%s' referenced in expression\n"),
601 else if (h->type == bfd_link_hash_new)
603 h->type = bfd_link_hash_undefined;
604 h->u.undef.abfd = NULL;
605 if (h->u.undef.next == NULL && h != link_info.hash->undefs_tail)
606 bfd_link_add_undef (link_info.hash, h);
612 if (allocation_done != lang_first_phase_enum)
614 lang_output_section_statement_type *os;
616 os = lang_output_section_find (tree->name.name);
617 if (os && os->processed > 0)
618 result = new_rel (0, NULL, os);
623 if (allocation_done != lang_first_phase_enum)
625 lang_output_section_statement_type *os;
627 os = lang_output_section_find (tree->name.name);
628 if (os && os->processed != 0)
630 if (os->load_base == NULL)
631 result = new_rel (0, NULL, os);
633 result = exp_fold_tree_no_dot (os->load_base,
641 if (allocation_done != lang_first_phase_enum)
643 int opb = bfd_octets_per_byte (output_bfd);
644 lang_output_section_statement_type *os;
646 os = lang_output_section_find (tree->name.name);
647 if (os && os->processed > 0)
648 result = new_abs (os->bfd_section->size / opb);
654 lang_memory_region_type *mem;
656 mem = lang_memory_region_lookup (tree->name.name, FALSE);
658 result = new_abs (mem->length);
660 einfo (_("%F%S: undefined MEMORY region `%s' referenced in expression\n"),
667 lang_memory_region_type *mem;
669 mem = lang_memory_region_lookup (tree->name.name, FALSE);
671 result = new_abs (mem->origin);
673 einfo (_("%F%S: undefined MEMORY region `%s' referenced in expression\n"),
687 exp_fold_tree (etree_type *tree,
688 lang_output_section_statement_type *current_section,
689 lang_phase_type allocation_done,
693 etree_value_type result;
697 result.valid_p = FALSE;
701 switch (tree->type.node_class)
704 result = new_rel (tree->value.value, tree->value.str, current_section);
708 if (allocation_done != lang_final_phase_enum)
709 result.valid_p = FALSE;
711 result = new_rel ((tree->rel.value
712 + tree->rel.section->output_section->vma
713 + tree->rel.section->output_offset),
719 result = exp_fold_tree (tree->assert_s.child,
721 allocation_done, dot, dotp);
725 einfo ("%X%P: %s\n", tree->assert_s.message);
731 result = fold_unary (tree, current_section, allocation_done,
736 result = fold_binary (tree, current_section, allocation_done,
741 result = fold_trinary (tree, current_section, allocation_done,
748 if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
750 /* Assignment to dot can only be done during allocation. */
751 if (tree->type.node_class != etree_assign)
752 einfo (_("%F%S can not PROVIDE assignment to location counter\n"));
753 if (allocation_done == lang_allocating_phase_enum
754 || (allocation_done == lang_final_phase_enum
755 && current_section == abs_output_section))
757 result = exp_fold_tree (tree->assign.src,
759 allocation_done, dot,
761 if (! result.valid_p)
762 einfo (_("%F%S invalid assignment to location counter\n"));
765 if (current_section == NULL)
766 einfo (_("%F%S assignment to location counter invalid outside of SECTION\n"));
771 nextdot = (result.value
772 + current_section->bfd_section->vma);
774 && current_section != abs_output_section)
775 einfo (_("%F%S cannot move location counter backwards (from %V to %V)\n"),
785 result = exp_fold_tree (tree->assign.src,
786 current_section, allocation_done,
791 struct bfd_link_hash_entry *h;
793 if (tree->type.node_class == etree_assign)
797 h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
798 create, FALSE, TRUE);
802 einfo (_("%P%F:%s: hash creation failed\n"),
805 else if (tree->type.node_class == etree_provide
806 && h->type != bfd_link_hash_new
807 && h->type != bfd_link_hash_undefined
808 && h->type != bfd_link_hash_common)
810 /* Do nothing. The symbol was defined by some
815 /* FIXME: Should we worry if the symbol is already
817 lang_update_definedness (tree->assign.dst, h);
818 h->type = bfd_link_hash_defined;
819 h->u.def.value = result.value;
820 h->u.def.section = result.section->bfd_section;
821 if (tree->type.node_class == etree_provide)
822 tree->type.node_class = etree_provided;
829 result = fold_name (tree, current_section, allocation_done, dot);
840 static etree_value_type
841 exp_fold_tree_no_dot (etree_type *tree,
842 lang_output_section_statement_type *current_section,
843 lang_phase_type allocation_done)
845 return exp_fold_tree (tree, current_section, allocation_done, 0, NULL);
849 exp_binop (int code, etree_type *lhs, etree_type *rhs)
851 etree_type value, *new;
854 value.type.node_code = code;
855 value.binary.lhs = lhs;
856 value.binary.rhs = rhs;
857 value.type.node_class = etree_binary;
858 r = exp_fold_tree_no_dot (&value,
860 lang_first_phase_enum);
863 return exp_intop (r.value);
865 new = stat_alloc (sizeof (new->binary));
866 memcpy (new, &value, sizeof (new->binary));
871 exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
873 etree_type value, *new;
875 value.type.node_code = code;
876 value.trinary.lhs = lhs;
877 value.trinary.cond = cond;
878 value.trinary.rhs = rhs;
879 value.type.node_class = etree_trinary;
880 r = exp_fold_tree_no_dot (&value, NULL, lang_first_phase_enum);
882 return exp_intop (r.value);
884 new = stat_alloc (sizeof (new->trinary));
885 memcpy (new, &value, sizeof (new->trinary));
890 exp_unop (int code, etree_type *child)
892 etree_type value, *new;
895 value.unary.type.node_code = code;
896 value.unary.child = child;
897 value.unary.type.node_class = etree_unary;
898 r = exp_fold_tree_no_dot (&value, abs_output_section,
899 lang_first_phase_enum);
901 return exp_intop (r.value);
903 new = stat_alloc (sizeof (new->unary));
904 memcpy (new, &value, sizeof (new->unary));
909 exp_nameop (int code, const char *name)
911 etree_type value, *new;
913 value.name.type.node_code = code;
914 value.name.name = name;
915 value.name.type.node_class = etree_name;
917 r = exp_fold_tree_no_dot (&value, NULL, lang_first_phase_enum);
919 return exp_intop (r.value);
921 new = stat_alloc (sizeof (new->name));
922 memcpy (new, &value, sizeof (new->name));
928 exp_assop (int code, const char *dst, etree_type *src)
930 etree_type value, *new;
932 value.assign.type.node_code = code;
934 value.assign.src = src;
935 value.assign.dst = dst;
936 value.assign.type.node_class = etree_assign;
938 new = stat_alloc (sizeof (new->assign));
939 memcpy (new, &value, sizeof (new->assign));
943 /* Handle PROVIDE. */
946 exp_provide (const char *dst, etree_type *src)
950 n = stat_alloc (sizeof (n->assign));
951 n->assign.type.node_code = '=';
952 n->assign.type.node_class = etree_provide;
961 exp_assert (etree_type *exp, const char *message)
965 n = stat_alloc (sizeof (n->assert_s));
966 n->assert_s.type.node_code = '!';
967 n->assert_s.type.node_class = etree_assert;
968 n->assert_s.child = exp;
969 n->assert_s.message = message;
974 exp_print_tree (etree_type *tree)
976 if (config.map_file == NULL)
977 config.map_file = stderr;
981 minfo ("NULL TREE\n");
985 switch (tree->type.node_class)
988 minfo ("0x%v", tree->value.value);
991 if (tree->rel.section->owner != NULL)
992 minfo ("%B:", tree->rel.section->owner);
993 minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
996 fprintf (config.map_file, "%s", tree->assign.dst);
997 exp_print_token (tree->type.node_code, TRUE);
998 exp_print_tree (tree->assign.src);
1001 case etree_provided:
1002 fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
1003 exp_print_tree (tree->assign.src);
1004 fprintf (config.map_file, ")");
1007 fprintf (config.map_file, "(");
1008 exp_print_tree (tree->binary.lhs);
1009 exp_print_token (tree->type.node_code, TRUE);
1010 exp_print_tree (tree->binary.rhs);
1011 fprintf (config.map_file, ")");
1014 exp_print_tree (tree->trinary.cond);
1015 fprintf (config.map_file, "?");
1016 exp_print_tree (tree->trinary.lhs);
1017 fprintf (config.map_file, ":");
1018 exp_print_tree (tree->trinary.rhs);
1021 exp_print_token (tree->unary.type.node_code, FALSE);
1022 if (tree->unary.child)
1024 fprintf (config.map_file, " (");
1025 exp_print_tree (tree->unary.child);
1026 fprintf (config.map_file, ")");
1031 fprintf (config.map_file, "ASSERT (");
1032 exp_print_tree (tree->assert_s.child);
1033 fprintf (config.map_file, ", %s)", tree->assert_s.message);
1037 fprintf (config.map_file, "????????");
1040 if (tree->type.node_code == NAME)
1042 fprintf (config.map_file, "%s", tree->name.name);
1046 exp_print_token (tree->type.node_code, FALSE);
1047 if (tree->name.name)
1048 fprintf (config.map_file, " (%s)", tree->name.name);
1058 exp_get_vma (etree_type *tree,
1061 lang_phase_type allocation_done)
1067 r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
1068 if (! r.valid_p && name != NULL)
1069 einfo (_("%F%S nonconstant expression for %s\n"), name);
1077 exp_get_value_int (etree_type *tree,
1080 lang_phase_type allocation_done)
1082 return exp_get_vma (tree, def, name, allocation_done);
1086 exp_get_fill (etree_type *tree,
1089 lang_phase_type allocation_done)
1099 r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
1100 if (! r.valid_p && name != NULL)
1101 einfo (_("%F%S nonconstant expression for %s\n"), name);
1103 if (r.str != NULL && (len = strlen (r.str)) != 0)
1107 fill = xmalloc ((len + 1) / 2 + sizeof (*fill) - 1);
1108 fill->size = (len + 1) / 2;
1118 digit = (digit - 'A' + '0' + 10) & 0xf;
1132 fill = xmalloc (4 + sizeof (*fill) - 1);
1134 fill->data[0] = (val >> 24) & 0xff;
1135 fill->data[1] = (val >> 16) & 0xff;
1136 fill->data[2] = (val >> 8) & 0xff;
1137 fill->data[3] = (val >> 0) & 0xff;
1144 exp_get_abs_int (etree_type *tree,
1145 int def ATTRIBUTE_UNUSED,
1147 lang_phase_type allocation_done)
1149 etree_value_type res;
1150 res = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
1153 res.value += res.section->bfd_section->vma;
1155 einfo (_("%F%S non constant expression for %s\n"), name);
1161 align_n (bfd_vma value, bfd_vma align)
1166 value = (value + align - 1) / align;
1167 return value * align;