1 /* This module handles expression trees.
2 Copyright (C) 1991, 1993, 1994, 1995 Free Software Foundation, Inc.
3 Written by Steve Chamberlain of Cygnus Support (sac@cygnus.com).
5 This file is part of GLD, the Gnu Linker.
7 GLD is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GLD is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GLD; see the file COPYING. If not, write to
19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
22 This module is in charge of working out the contents of expressions.
24 It has to keep track of the relative/absness of a symbol etc. This is
25 done by keeping all values in a struct (an etree_value_type) which
26 contains a value, a section to which it is relative and a valid bit.
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)
77 { REL, "relocateable" },
97 { SECTIONS,"SECTIONS" },
98 { SIZEOF_HEADERS,"SIZEOF_HEADERS" },
103 { DEFINED,"DEFINED" },
104 { TARGET_K,"TARGET" },
105 { SEARCH_DIR,"SEARCH_DIR" },
116 for (idx = 0; table[idx].name != (char*)NULL; idx++) {
117 if (table[idx].code == code) {
118 fprintf(config.map_file, "%s", table[idx].name);
122 /* Not in table, just print it alone */
123 fprintf(config.map_file, "%c",code);
128 etree_value_type *ptr;
130 asection *s = ptr->section->bfd_section;
131 ptr->value += s->vma;
132 ptr->section = abs_output_section;
135 static etree_value_type
139 etree_value_type new;
141 new.section = abs_output_section;
148 lang_output_section_statement_type *os;
152 if (os == (lang_output_section_statement_type *)NULL) {
153 einfo("%F%P: %s uses undefined section %s\n", op, name);
155 if (os->processed == false) {
156 einfo("%F%P: %s forward reference of section %s\n",op, name);
164 etree_type *new = (etree_type *)stat_alloc((bfd_size_type)(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 && (result.section == abs_output_section
242 || other.section == abs_output_section)
243 && (tree->type.node_code == '+'
244 || tree->type.node_code == '-'))
246 etree_value_type hold;
248 /* If there is only one absolute term, make sure it is the
250 if (result.section == abs_output_section)
257 else if (result.section != other.section
258 || current_section == abs_output_section)
264 switch (tree->type.node_code)
267 if (other.value == 0)
268 einfo ("%F%S %% by zero\n");
269 result.value = ((bfd_signed_vma) result.value
270 % (bfd_signed_vma) other.value);
274 if (other.value == 0)
275 einfo ("%F%S / by zero\n");
276 result.value = ((bfd_signed_vma) result.value
277 / (bfd_signed_vma) other.value);
280 #define BOP(x,y) case x : result.value = result.value y other.value; break;
304 result.valid = false;
314 etree_value_type new;
319 static etree_value_type
320 fold_name (tree, current_section, allocation_done, dot)
322 lang_output_section_statement_type *current_section;
323 lang_phase_type allocation_done;
326 etree_value_type result;
327 switch (tree->type.node_code)
330 if (allocation_done != lang_first_phase_enum)
332 result = new_abs ((bfd_vma)
333 bfd_sizeof_headers (output_bfd,
334 link_info.relocateable));
338 result.valid = false;
342 if (allocation_done == lang_first_phase_enum)
343 result.valid = false;
346 struct bfd_link_hash_entry *h;
348 h = bfd_link_hash_lookup (link_info.hash, tree->name.name,
350 result.value = (h != (struct bfd_link_hash_entry *) NULL
351 && (h->type == bfd_link_hash_defined
352 || h->type == bfd_link_hash_common));
358 result.valid = false;
359 if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
361 if (allocation_done != lang_first_phase_enum)
362 result = new_rel_from_section(dot, current_section);
366 else if (allocation_done != lang_first_phase_enum)
368 struct bfd_link_hash_entry *h;
370 h = bfd_link_hash_lookup (link_info.hash, tree->name.name,
372 if (h != NULL && h->type == bfd_link_hash_defined)
374 if (bfd_is_abs_section (h->u.def.section))
375 result = new_abs (h->u.def.value);
376 else if (allocation_done == lang_final_phase_enum)
378 lang_output_section_statement_type *os;
380 os = (lang_output_section_statement_lookup
381 (h->u.def.section->output_section->name));
383 /* FIXME: Is this correct if this section is being
385 result = new_rel ((h->u.def.value
386 + h->u.def.section->output_offset),
390 else if (allocation_done == lang_final_phase_enum)
391 einfo ("%F%S: undefined symbol `%s' referenced in expression\n",
398 if (allocation_done != lang_first_phase_enum) {
399 lang_output_section_statement_type *os =
400 lang_output_section_find(tree->name.name);
401 check(os,tree->name.name,"ADDR");
402 result = new_rel((bfd_vma)0, os);
409 if(allocation_done != lang_first_phase_enum) {
410 lang_output_section_statement_type *os =
411 lang_output_section_find(tree->name.name);
412 check(os,tree->name.name,"SIZEOF");
413 result = new_abs((bfd_vma)(os->bfd_section->_raw_size));
428 exp_fold_tree (tree, current_section, allocation_done, dot, dotp)
430 lang_output_section_statement_type *current_section;
431 lang_phase_type allocation_done;
435 etree_value_type result;
437 if (tree == (etree_type *)NULL) {
438 result.valid = false;
441 switch (tree->type.node_class)
444 result = new_rel(tree->value.value, current_section);
447 if (allocation_done != lang_final_phase_enum)
448 result.valid = false;
450 result = new_rel ((tree->rel.value
451 + tree->rel.section->output_section->vma
452 + tree->rel.section->output_offset),
456 result = exp_fold_tree(tree->unary.child,
458 allocation_done, dot, dotp);
459 if (result.valid == true)
461 switch(tree->type.node_code)
464 if (allocation_done != lang_first_phase_enum) {
465 result = new_rel_from_section(ALIGN_N(dot,
471 result.valid = false;
475 if (allocation_done != lang_first_phase_enum)
478 == (lang_output_section_statement_type*)NULL)
480 /* Outside a section, so it's all ok */
484 /* Inside a section, subtract the base of the section,
485 so when it's added again (in an assignment), everything comes out fine
487 result.section = abs_output_section;
488 result.value -= current_section->bfd_section->vma;
494 result.valid = false;
500 result.value = ~result.value;
504 result.value = !result.value;
508 result.value = -result.value;
511 if (allocation_done ==lang_allocating_phase_enum) {
513 result.value = ALIGN_N(dot, result.value);
516 /* Return next place aligned to value */
517 result.valid = false;
528 result = exp_fold_tree(tree->trinary.cond,
530 allocation_done, dot, dotp);
532 result = exp_fold_tree(result.value ?
533 tree->trinary.lhs:tree->trinary.rhs,
535 allocation_done, dot, dotp);
540 result = fold_binary(tree, current_section, allocation_done,
545 if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0) {
546 /* Assignment to dot can only be done during allocation */
547 if (tree->type.node_class == etree_provide)
548 einfo ("%F%S can not PROVIDE assignment to location counter\n");
549 if (allocation_done == lang_allocating_phase_enum) {
550 result = exp_fold_tree(tree->assign.src,
552 lang_allocating_phase_enum, dot, dotp);
553 if (result.valid == false) {
554 einfo("%F%S invalid assignment to location counter\n");
557 if (current_section ==
558 (lang_output_section_statement_type *)NULL) {
559 einfo("%F%S assignment to location counter invalid outside of SECTION\n");
562 bfd_vma nextdot =result.value +
563 current_section->bfd_section->vma;
565 einfo("%F%S cannot move location counter backwards (from %V to %V)\n", dot, nextdot);
576 result = exp_fold_tree (tree->assign.src,
577 current_section, allocation_done,
581 struct bfd_link_hash_entry *h;
583 h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
584 (tree->type.node_class == etree_assign
587 if (h == (struct bfd_link_hash_entry *) NULL)
589 if (tree->type.node_class == etree_assign)
590 einfo ("%P%F:%s: hash creation failed\n",
593 else if (tree->type.node_class == etree_provide
594 && h->type != bfd_link_hash_undefined
595 && h->type != bfd_link_hash_common)
597 /* Do nothing. The symbol was defined by some
602 /* FIXME: Should we worry if the symbol is already
604 h->type = bfd_link_hash_defined;
605 h->u.def.value = result.value;
606 h->u.def.section = result.section->bfd_section;
612 result = fold_name(tree, current_section, allocation_done, dot);
615 einfo("%F%S need more of these %d\n",tree->type.node_class );
624 static etree_value_type
625 exp_fold_tree_no_dot (tree, current_section, allocation_done)
627 lang_output_section_statement_type *current_section;
628 lang_phase_type allocation_done;
630 return exp_fold_tree(tree, current_section, allocation_done, (bfd_vma)
635 exp_binop (code, lhs, rhs)
640 etree_type value, *new;
643 value.type.node_code = code;
644 value.binary.lhs = lhs;
645 value.binary.rhs = rhs;
646 value.type.node_class = etree_binary;
647 r = exp_fold_tree_no_dot(&value,
649 lang_first_phase_enum );
652 return exp_intop(r.value);
654 new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->binary)));
655 memcpy((char *)new, (char *)&value, sizeof(new->binary));
660 exp_trinop (code, cond, lhs, rhs)
666 etree_type value, *new;
668 value.type.node_code = code;
669 value.trinary.lhs = lhs;
670 value.trinary.cond = cond;
671 value.trinary.rhs = rhs;
672 value.type.node_class = etree_trinary;
673 r= exp_fold_tree_no_dot(&value, (lang_output_section_statement_type
674 *)NULL,lang_first_phase_enum);
676 return exp_intop(r.value);
678 new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->trinary)));
679 memcpy((char *)new,(char *) &value, sizeof(new->trinary));
685 exp_unop (code, child)
689 etree_type value, *new;
692 value.unary.type.node_code = code;
693 value.unary.child = child;
694 value.unary.type.node_class = etree_unary;
695 r = exp_fold_tree_no_dot(&value,abs_output_section,
696 lang_first_phase_enum);
698 return exp_intop(r.value);
700 new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->unary)));
701 memcpy((char *)new, (char *)&value, sizeof(new->unary));
707 exp_nameop (code, name)
711 etree_type value, *new;
713 value.name.type.node_code = code;
714 value.name.name = name;
715 value.name.type.node_class = etree_name;
718 r = exp_fold_tree_no_dot(&value,
719 (lang_output_section_statement_type *)NULL,
720 lang_first_phase_enum);
722 return exp_intop(r.value);
724 new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->name)));
725 memcpy((char *)new, (char *)&value, sizeof(new->name));
734 exp_assop (code, dst, src)
739 etree_type value, *new;
741 value.assign.type.node_code = code;
744 value.assign.src = src;
745 value.assign.dst = dst;
746 value.assign.type.node_class = etree_assign;
749 if (exp_fold_tree_no_dot(&value, &result)) {
750 return exp_intop(result);
753 new = (etree_type*)stat_alloc((bfd_size_type)(sizeof(new->assign)));
754 memcpy((char *)new, (char *)&value, sizeof(new->assign));
758 /* Handle PROVIDE. */
761 exp_provide (dst, src)
767 n = (etree_type *) stat_alloc (sizeof (n->assign));
768 n->assign.type.node_code = '=';
769 n->assign.type.node_class = etree_provide;
776 exp_print_tree (tree)
779 switch (tree->type.node_class) {
781 print_address(tree->value.value);
784 if (tree->rel.section->owner != NULL)
785 fprintf (config.map_file, "%s:",
786 bfd_get_filename (tree->rel.section->owner));
787 fprintf (config.map_file, "%s+", tree->rel.section->name);
788 print_address (tree->rel.value);
792 if (tree->assign.dst->sdefs != (asymbol *)NULL){
793 fprintf(config.map_file,"%s (%x) ",tree->assign.dst->name,
794 tree->assign.dst->sdefs->value);
797 fprintf(config.map_file,"%s (UNDEFINED)",tree->assign.dst->name);
800 fprintf(config.map_file,"%s ",tree->assign.dst);
801 exp_print_token(tree->type.node_code);
802 exp_print_tree(tree->assign.src);
805 fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
806 exp_print_tree (tree->assign.src);
807 fprintf (config.map_file, ")");
810 fprintf(config.map_file,"(");
811 exp_print_tree(tree->binary.lhs);
812 exp_print_token(tree->type.node_code);
813 exp_print_tree(tree->binary.rhs);
814 fprintf(config.map_file,")");
817 exp_print_tree(tree->trinary.cond);
818 fprintf(config.map_file,"?");
819 exp_print_tree(tree->trinary.lhs);
820 fprintf(config.map_file,":");
821 exp_print_tree(tree->trinary.rhs);
824 exp_print_token(tree->unary.type.node_code);
825 if (tree->unary.child)
828 fprintf(config.map_file,"(");
829 exp_print_tree(tree->unary.child);
830 fprintf(config.map_file,")");
835 fprintf(config.map_file,"????????");
838 if (tree->type.node_code == NAME) {
839 fprintf(config.map_file,"%s", tree->name.name);
842 exp_print_token(tree->type.node_code);
844 fprintf(config.map_file,"(%s)", tree->name.name);
857 exp_get_vma (tree, def, name, allocation_done)
861 lang_phase_type allocation_done;
865 if (tree != (etree_type *)NULL) {
866 r = exp_fold_tree_no_dot(tree,
869 if (r.valid == false && name) {
870 einfo("%F%S nonconstant expression for %s\n",name);
880 exp_get_value_int (tree,def,name, allocation_done)
884 lang_phase_type allocation_done;
886 return (int)exp_get_vma(tree,(bfd_vma)def,name, allocation_done);
891 exp_get_abs_int (tree, def, name, allocation_done)
895 lang_phase_type allocation_done;
897 etree_value_type res;
898 res = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
902 res.value += res.section->bfd_section->vma;
905 einfo ("%F%S non constant expression for %s\n",name);