xref: /netbsd-src/external/gpl3/binutils/dist/ld/ldexp.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* This module handles expression trees.
2    Copyright (C) 1991-2018 Free Software Foundation, Inc.
3    Written by Steve Chamberlain of Cygnus Support <sac@cygnus.com>.
4 
5    This file is part of the GNU Binutils.
6 
7    This program 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 3 of the License, or
10    (at your option) any later version.
11 
12    This program 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.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 
23 /* This module is in charge of working out the contents of expressions.
24 
25    It has to keep track of the relative/absness of a symbol etc. This
26    is done by keeping all values in a struct (an etree_value_type)
27    which contains a value, a section to which it is relative and a
28    valid bit.  */
29 
30 #include "sysdep.h"
31 #include "bfd.h"
32 #include "bfdlink.h"
33 
34 #include "ld.h"
35 #include "ldmain.h"
36 #include "ldmisc.h"
37 #include "ldexp.h"
38 #include "ldlex.h"
39 #include <ldgram.h>
40 #include "ldlang.h"
41 #include "libiberty.h"
42 #include "safe-ctype.h"
43 
44 static void exp_fold_tree_1 (etree_type *);
45 static bfd_vma align_n (bfd_vma, bfd_vma);
46 
47 segment_type *segments;
48 
49 struct ldexp_control expld;
50 
51 /* This structure records symbols for which we need to keep track of
52    definedness for use in the DEFINED () test.  It is also used in
53    making absolute symbols section relative late in the link.   */
54 
55 struct definedness_hash_entry
56 {
57   struct bfd_hash_entry root;
58 
59   /* If this symbol was assigned from "dot" outside of an output
60      section statement, the section we'd like it relative to.  */
61   asection *final_sec;
62 
63   /* Low bits of iteration count.  Symbols with matching iteration have
64      been defined in this pass over the script.  */
65   unsigned int iteration : 8;
66 
67   /* Symbol was defined by an object file.  */
68   unsigned int by_object : 1;
69 };
70 
71 static struct bfd_hash_table definedness_table;
72 
73 /* Print the string representation of the given token.  Surround it
74    with spaces if INFIX_P is TRUE.  */
75 
76 static void
77 exp_print_token (token_code_type code, int infix_p)
78 {
79   static const struct
80   {
81     token_code_type code;
82     const char *name;
83   }
84   table[] =
85   {
86     { INT, "int" },
87     { NAME, "NAME" },
88     { PLUSEQ, "+=" },
89     { MINUSEQ, "-=" },
90     { MULTEQ, "*=" },
91     { DIVEQ, "/=" },
92     { LSHIFTEQ, "<<=" },
93     { RSHIFTEQ, ">>=" },
94     { ANDEQ, "&=" },
95     { OREQ, "|=" },
96     { OROR, "||" },
97     { ANDAND, "&&" },
98     { EQ, "==" },
99     { NE, "!=" },
100     { LE, "<=" },
101     { GE, ">=" },
102     { LSHIFT, "<<" },
103     { RSHIFT, ">>" },
104     { LOG2CEIL, "LOG2CEIL" },
105     { ALIGN_K, "ALIGN" },
106     { BLOCK, "BLOCK" },
107     { QUAD, "QUAD" },
108     { SQUAD, "SQUAD" },
109     { LONG, "LONG" },
110     { SHORT, "SHORT" },
111     { BYTE, "BYTE" },
112     { SECTIONS, "SECTIONS" },
113     { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
114     { MEMORY, "MEMORY" },
115     { DEFINED, "DEFINED" },
116     { TARGET_K, "TARGET" },
117     { SEARCH_DIR, "SEARCH_DIR" },
118     { MAP, "MAP" },
119     { ENTRY, "ENTRY" },
120     { NEXT, "NEXT" },
121     { ALIGNOF, "ALIGNOF" },
122     { SIZEOF, "SIZEOF" },
123     { ADDR, "ADDR" },
124     { LOADADDR, "LOADADDR" },
125     { CONSTANT, "CONSTANT" },
126     { ABSOLUTE, "ABSOLUTE" },
127     { MAX_K, "MAX" },
128     { MIN_K, "MIN" },
129     { ASSERT_K, "ASSERT" },
130     { REL, "relocatable" },
131     { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
132     { DATA_SEGMENT_RELRO_END, "DATA_SEGMENT_RELRO_END" },
133     { DATA_SEGMENT_END, "DATA_SEGMENT_END" },
134     { ORIGIN, "ORIGIN" },
135     { LENGTH, "LENGTH" },
136     { SEGMENT_START, "SEGMENT_START" }
137   };
138   unsigned int idx;
139 
140   for (idx = 0; idx < ARRAY_SIZE (table); idx++)
141     if (table[idx].code == code)
142       break;
143 
144   if (infix_p)
145     fputc (' ', config.map_file);
146 
147   if (idx < ARRAY_SIZE (table))
148     fputs (table[idx].name, config.map_file);
149   else if (code < 127)
150     fputc (code, config.map_file);
151   else
152     fprintf (config.map_file, "<code %d>", code);
153 
154   if (infix_p)
155     fputc (' ', config.map_file);
156 }
157 
158 static void
159 make_log2ceil (void)
160 {
161   bfd_vma value = expld.result.value;
162   bfd_vma result = -1;
163   bfd_boolean round_up = FALSE;
164 
165   do
166     {
167       result++;
168       /* If more than one bit is set in the value we will need to round up.  */
169       if ((value > 1) && (value & 1))
170 	round_up = TRUE;
171     }
172   while (value >>= 1);
173 
174   if (round_up)
175     result += 1;
176   expld.result.section = NULL;
177   expld.result.value = result;
178 }
179 
180 static void
181 make_abs (void)
182 {
183   if (expld.result.section != NULL)
184     expld.result.value += expld.result.section->vma;
185   expld.result.section = bfd_abs_section_ptr;
186   expld.rel_from_abs = FALSE;
187 }
188 
189 static void
190 new_abs (bfd_vma value)
191 {
192   expld.result.valid_p = TRUE;
193   expld.result.section = bfd_abs_section_ptr;
194   expld.result.value = value;
195   expld.result.str = NULL;
196 }
197 
198 etree_type *
199 exp_intop (bfd_vma value)
200 {
201   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
202   new_e->type.node_code = INT;
203   new_e->type.filename = ldlex_filename ();
204   new_e->type.lineno = lineno;
205   new_e->value.value = value;
206   new_e->value.str = NULL;
207   new_e->type.node_class = etree_value;
208   return new_e;
209 }
210 
211 etree_type *
212 exp_bigintop (bfd_vma value, char *str)
213 {
214   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
215   new_e->type.node_code = INT;
216   new_e->type.filename = ldlex_filename ();
217   new_e->type.lineno = lineno;
218   new_e->value.value = value;
219   new_e->value.str = str;
220   new_e->type.node_class = etree_value;
221   return new_e;
222 }
223 
224 /* Build an expression representing an unnamed relocatable value.  */
225 
226 etree_type *
227 exp_relop (asection *section, bfd_vma value)
228 {
229   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->rel));
230   new_e->type.node_code = REL;
231   new_e->type.filename = ldlex_filename ();
232   new_e->type.lineno = lineno;
233   new_e->type.node_class = etree_rel;
234   new_e->rel.section = section;
235   new_e->rel.value = value;
236   return new_e;
237 }
238 
239 static void
240 new_number (bfd_vma value)
241 {
242   expld.result.valid_p = TRUE;
243   expld.result.value = value;
244   expld.result.str = NULL;
245   expld.result.section = NULL;
246 }
247 
248 static void
249 new_rel (bfd_vma value, asection *section)
250 {
251   expld.result.valid_p = TRUE;
252   expld.result.value = value;
253   expld.result.str = NULL;
254   expld.result.section = section;
255 }
256 
257 static void
258 new_rel_from_abs (bfd_vma value)
259 {
260   asection *s = expld.section;
261 
262   expld.rel_from_abs = TRUE;
263   expld.result.valid_p = TRUE;
264   expld.result.value = value - s->vma;
265   expld.result.str = NULL;
266   expld.result.section = s;
267 }
268 
269 /* New-function for the definedness hash table.  */
270 
271 static struct bfd_hash_entry *
272 definedness_newfunc (struct bfd_hash_entry *entry,
273 		     struct bfd_hash_table *table ATTRIBUTE_UNUSED,
274 		     const char *name ATTRIBUTE_UNUSED)
275 {
276   struct definedness_hash_entry *ret = (struct definedness_hash_entry *) entry;
277 
278   if (ret == NULL)
279     ret = (struct definedness_hash_entry *)
280       bfd_hash_allocate (table, sizeof (struct definedness_hash_entry));
281 
282   if (ret == NULL)
283     einfo (_("%P%F: bfd_hash_allocate failed creating symbol %s\n"), name);
284 
285   ret->by_object = 0;
286   ret->iteration = 0;
287   return &ret->root;
288 }
289 
290 /* Called during processing of linker script script expressions.
291    For symbols assigned in a linker script, return a struct describing
292    where the symbol is defined relative to the current expression,
293    otherwise return NULL.  */
294 
295 static struct definedness_hash_entry *
296 symbol_defined (const char *name)
297 {
298   return ((struct definedness_hash_entry *)
299 	  bfd_hash_lookup (&definedness_table, name, FALSE, FALSE));
300 }
301 
302 /* Update the definedness state of NAME.  Return FALSE if script symbol
303    is multiply defining a strong symbol in an object.  */
304 
305 static bfd_boolean
306 update_definedness (const char *name, struct bfd_link_hash_entry *h)
307 {
308   bfd_boolean ret;
309   struct definedness_hash_entry *defentry
310     = (struct definedness_hash_entry *)
311     bfd_hash_lookup (&definedness_table, name, TRUE, FALSE);
312 
313   if (defentry == NULL)
314     einfo (_("%P%F: bfd_hash_lookup failed creating symbol %s\n"), name);
315 
316   /* If the symbol was already defined, and not by a script, then it
317      must be defined by an object file or by the linker target code.  */
318   ret = TRUE;
319   if (!h->ldscript_def
320       && (h->type == bfd_link_hash_defined
321 	  || h->type == bfd_link_hash_defweak
322 	  || h->type == bfd_link_hash_common))
323     {
324       defentry->by_object = 1;
325       if (h->type == bfd_link_hash_defined
326 	  && h->u.def.section->output_section != NULL
327 	  && !h->linker_def)
328 	ret = FALSE;
329     }
330 
331   defentry->iteration = lang_statement_iteration;
332   defentry->final_sec = bfd_abs_section_ptr;
333   if (expld.phase == lang_final_phase_enum
334       && expld.rel_from_abs
335       && expld.result.section == bfd_abs_section_ptr)
336     defentry->final_sec = section_for_dot ();
337   return ret;
338 }
339 
340 static void
341 fold_segment_end (seg_align_type *seg)
342 {
343   if (expld.phase == lang_first_phase_enum
344       || expld.section != bfd_abs_section_ptr)
345     {
346       expld.result.valid_p = FALSE;
347     }
348   else if (seg->phase == exp_seg_align_seen
349 	   || seg->phase == exp_seg_relro_seen)
350     {
351       seg->phase = exp_seg_end_seen;
352       seg->end = expld.result.value;
353     }
354   else if (seg->phase == exp_seg_done
355 	   || seg->phase == exp_seg_adjust
356 	   || seg->phase == exp_seg_relro_adjust)
357     {
358       /* OK.  */
359     }
360   else
361     expld.result.valid_p = FALSE;
362 }
363 
364 static void
365 fold_unary (etree_type *tree)
366 {
367   exp_fold_tree_1 (tree->unary.child);
368   if (expld.result.valid_p)
369     {
370       switch (tree->type.node_code)
371 	{
372 	case ALIGN_K:
373 	  if (expld.phase != lang_first_phase_enum)
374 	    new_rel_from_abs (align_n (expld.dot, expld.result.value));
375 	  else
376 	    expld.result.valid_p = FALSE;
377 	  break;
378 
379 	case ABSOLUTE:
380 	  make_abs ();
381 	  break;
382 
383 	case LOG2CEIL:
384 	  make_log2ceil ();
385 	  break;
386 
387 	case '~':
388 	  expld.result.value = ~expld.result.value;
389 	  break;
390 
391 	case '!':
392 	  expld.result.value = !expld.result.value;
393 	  break;
394 
395 	case '-':
396 	  expld.result.value = -expld.result.value;
397 	  break;
398 
399 	case NEXT:
400 	  /* Return next place aligned to value.  */
401 	  if (expld.phase != lang_first_phase_enum)
402 	    {
403 	      make_abs ();
404 	      expld.result.value = align_n (expld.dot, expld.result.value);
405 	    }
406 	  else
407 	    expld.result.valid_p = FALSE;
408 	  break;
409 
410 	case DATA_SEGMENT_END:
411 	  fold_segment_end (&expld.dataseg);
412 	  break;
413 
414 	default:
415 	  FAIL ();
416 	  break;
417 	}
418     }
419 }
420 
421 /* Arithmetic operators, bitwise AND, bitwise OR and XOR keep the
422    section of one of their operands only when the other operand is a
423    plain number.  Losing the section when operating on two symbols,
424    ie. a result of a plain number, is required for subtraction and
425    XOR.  It's justifiable for the other operations on the grounds that
426    adding, multiplying etc. two section relative values does not
427    really make sense unless they are just treated as numbers.
428    The same argument could be made for many expressions involving one
429    symbol and a number.  For example, "1 << x" and "100 / x" probably
430    should not be given the section of x.  The trouble is that if we
431    fuss about such things the rules become complex and it is onerous
432    to document ld expression evaluation.  */
433 static void
434 arith_result_section (const etree_value_type *lhs)
435 {
436   if (expld.result.section == lhs->section)
437     {
438       if (expld.section == bfd_abs_section_ptr
439 	  && !config.sane_expr)
440 	/* Duplicate the insanity in exp_fold_tree_1 case etree_value.  */
441 	expld.result.section = bfd_abs_section_ptr;
442       else
443 	expld.result.section = NULL;
444     }
445 }
446 
447 static void
448 fold_segment_align (seg_align_type *seg, etree_value_type *lhs)
449 {
450   seg->relro = exp_seg_relro_start;
451   if (expld.phase == lang_first_phase_enum
452       || expld.section != bfd_abs_section_ptr)
453     expld.result.valid_p = FALSE;
454   else
455     {
456       bfd_vma maxpage = lhs->value;
457       bfd_vma commonpage = expld.result.value;
458 
459       expld.result.value = align_n (expld.dot, maxpage);
460       if (seg->phase == exp_seg_relro_adjust)
461 	expld.result.value = seg->base;
462       else if (seg->phase == exp_seg_adjust)
463 	{
464 	  if (commonpage < maxpage)
465 	    expld.result.value += ((expld.dot + commonpage - 1)
466 				   & (maxpage - commonpage));
467 	}
468       else
469 	{
470 	  expld.result.value += expld.dot & (maxpage - 1);
471 	  if (seg->phase == exp_seg_done)
472 	    {
473 	      /* OK.  */
474 	    }
475 	  else if (seg->phase == exp_seg_none)
476 	    {
477 	      seg->phase = exp_seg_align_seen;
478 	      seg->base = expld.result.value;
479 	      seg->pagesize = commonpage;
480 	      seg->maxpagesize = maxpage;
481 	      seg->relro_end = 0;
482 	    }
483 	  else
484 	    expld.result.valid_p = FALSE;
485 	}
486     }
487 }
488 
489 static void
490 fold_segment_relro_end (seg_align_type *seg, etree_value_type *lhs)
491 {
492   /* Operands swapped!  XXX_SEGMENT_RELRO_END(offset,exp) has offset
493      in expld.result and exp in lhs.  */
494   seg->relro = exp_seg_relro_end;
495   seg->relro_offset = expld.result.value;
496   if (expld.phase == lang_first_phase_enum
497       || expld.section != bfd_abs_section_ptr)
498     expld.result.valid_p = FALSE;
499   else if (seg->phase == exp_seg_align_seen
500 	   || seg->phase == exp_seg_adjust
501 	   || seg->phase == exp_seg_relro_adjust
502 	   || seg->phase == exp_seg_done)
503     {
504       if (seg->phase == exp_seg_align_seen
505 	  || seg->phase == exp_seg_relro_adjust)
506 	seg->relro_end = lhs->value + expld.result.value;
507 
508       if (seg->phase == exp_seg_relro_adjust
509 	  && (seg->relro_end & (seg->pagesize - 1)))
510 	{
511 	  seg->relro_end += seg->pagesize - 1;
512 	  seg->relro_end &= ~(seg->pagesize - 1);
513 	  expld.result.value = seg->relro_end - expld.result.value;
514 	}
515       else
516 	expld.result.value = lhs->value;
517 
518       if (seg->phase == exp_seg_align_seen)
519 	seg->phase = exp_seg_relro_seen;
520     }
521   else
522     expld.result.valid_p = FALSE;
523 }
524 
525 static void
526 fold_binary (etree_type *tree)
527 {
528   etree_value_type lhs;
529   exp_fold_tree_1 (tree->binary.lhs);
530 
531   /* The SEGMENT_START operator is special because its first
532      operand is a string, not the name of a symbol.  Note that the
533      operands have been swapped, so binary.lhs is second (default)
534      operand, binary.rhs is first operand.  */
535   if (expld.result.valid_p && tree->type.node_code == SEGMENT_START)
536     {
537       const char *segment_name;
538       segment_type *seg;
539 
540       /* Check to see if the user has overridden the default
541 	 value.  */
542       segment_name = tree->binary.rhs->name.name;
543       for (seg = segments; seg; seg = seg->next)
544 	if (strcmp (seg->name, segment_name) == 0)
545 	  {
546 	    if (!seg->used
547 		&& config.magic_demand_paged
548 		&& (seg->value % config.maxpagesize) != 0)
549 	      einfo (_("%P: warning: address of `%s' "
550 		       "isn't multiple of maximum page size\n"),
551 		     segment_name);
552 	    seg->used = TRUE;
553 	    new_rel_from_abs (seg->value);
554 	    break;
555 	  }
556       return;
557     }
558 
559   lhs = expld.result;
560   exp_fold_tree_1 (tree->binary.rhs);
561   expld.result.valid_p &= lhs.valid_p;
562 
563   if (expld.result.valid_p)
564     {
565       if (lhs.section != expld.result.section)
566 	{
567 	  /* If the values are from different sections, and neither is
568 	     just a number, make both the source arguments absolute.  */
569 	  if (expld.result.section != NULL
570 	      && lhs.section != NULL)
571 	    {
572 	      make_abs ();
573 	      lhs.value += lhs.section->vma;
574 	      lhs.section = bfd_abs_section_ptr;
575 	    }
576 
577 	  /* If the rhs is just a number, keep the lhs section.  */
578 	  else if (expld.result.section == NULL)
579 	    {
580 	      expld.result.section = lhs.section;
581 	      /* Make this NULL so that we know one of the operands
582 		 was just a number, for later tests.  */
583 	      lhs.section = NULL;
584 	    }
585 	}
586       /* At this point we know that both operands have the same
587 	 section, or at least one of them is a plain number.  */
588 
589       switch (tree->type.node_code)
590 	{
591 #define BOP(x, y) \
592 	case x:							\
593 	  expld.result.value = lhs.value y expld.result.value;	\
594 	  arith_result_section (&lhs);				\
595 	  break;
596 
597 	  /* Comparison operators, logical AND, and logical OR always
598 	     return a plain number.  */
599 #define BOPN(x, y) \
600 	case x:							\
601 	  expld.result.value = lhs.value y expld.result.value;	\
602 	  expld.result.section = NULL;				\
603 	  break;
604 
605 	  BOP ('+', +);
606 	  BOP ('*', *);
607 	  BOP ('-', -);
608 	  BOP (LSHIFT, <<);
609 	  BOP (RSHIFT, >>);
610 	  BOP ('&', &);
611 	  BOP ('^', ^);
612 	  BOP ('|', |);
613 	  BOPN (EQ, ==);
614 	  BOPN (NE, !=);
615 	  BOPN ('<', <);
616 	  BOPN ('>', >);
617 	  BOPN (LE, <=);
618 	  BOPN (GE, >=);
619 	  BOPN (ANDAND, &&);
620 	  BOPN (OROR, ||);
621 
622 	case '%':
623 	  if (expld.result.value != 0)
624 	    expld.result.value = ((bfd_signed_vma) lhs.value
625 				  % (bfd_signed_vma) expld.result.value);
626 	  else if (expld.phase != lang_mark_phase_enum)
627 	    einfo (_("%F%S %% by zero\n"), tree->binary.rhs);
628 	  arith_result_section (&lhs);
629 	  break;
630 
631 	case '/':
632 	  if (expld.result.value != 0)
633 	    expld.result.value = ((bfd_signed_vma) lhs.value
634 				  / (bfd_signed_vma) expld.result.value);
635 	  else if (expld.phase != lang_mark_phase_enum)
636 	    einfo (_("%F%S / by zero\n"), tree->binary.rhs);
637 	  arith_result_section (&lhs);
638 	  break;
639 
640 	case MAX_K:
641 	  if (lhs.value > expld.result.value)
642 	    expld.result.value = lhs.value;
643 	  break;
644 
645 	case MIN_K:
646 	  if (lhs.value < expld.result.value)
647 	    expld.result.value = lhs.value;
648 	  break;
649 
650 	case ALIGN_K:
651 	  expld.result.value = align_n (lhs.value, expld.result.value);
652 	  break;
653 
654 	case DATA_SEGMENT_ALIGN:
655 	  fold_segment_align (&expld.dataseg, &lhs);
656 	  break;
657 
658 	case DATA_SEGMENT_RELRO_END:
659 	  fold_segment_relro_end (&expld.dataseg, &lhs);
660 	  break;
661 
662 	default:
663 	  FAIL ();
664 	}
665     }
666 }
667 
668 static void
669 fold_trinary (etree_type *tree)
670 {
671   struct bfd_link_hash_entry *save = expld.assign_src;
672 
673   exp_fold_tree_1 (tree->trinary.cond);
674   expld.assign_src = save;
675   if (expld.result.valid_p)
676     exp_fold_tree_1 (expld.result.value
677 		     ? tree->trinary.lhs
678 		     : tree->trinary.rhs);
679 }
680 
681 static void
682 fold_name (etree_type *tree)
683 {
684   struct bfd_link_hash_entry *h;
685   struct definedness_hash_entry *def;
686 
687   memset (&expld.result, 0, sizeof (expld.result));
688 
689   switch (tree->type.node_code)
690     {
691     case SIZEOF_HEADERS:
692       if (expld.phase != lang_first_phase_enum)
693 	{
694 	  bfd_vma hdr_size = 0;
695 	  /* Don't find the real header size if only marking sections;
696 	     The bfd function may cache incorrect data.  */
697 	  if (expld.phase != lang_mark_phase_enum)
698 	    hdr_size = bfd_sizeof_headers (link_info.output_bfd, &link_info);
699 	  new_number (hdr_size);
700 	}
701       break;
702 
703     case DEFINED:
704       h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
705 					&link_info,
706 					tree->name.name,
707 					FALSE, FALSE, TRUE);
708       new_number (h != NULL
709 		  && (h->type == bfd_link_hash_defined
710 		      || h->type == bfd_link_hash_defweak
711 		      || h->type == bfd_link_hash_common)
712 		  && (!h->ldscript_def
713 		      || (def = symbol_defined (tree->name.name)) == NULL
714 		      || def->by_object
715 		      || def->iteration == (lang_statement_iteration & 255)));
716       break;
717 
718     case NAME:
719       if (expld.assign_name != NULL
720 	  && strcmp (expld.assign_name, tree->name.name) == 0)
721 	{
722 	  /* Self-assignment is only allowed for absolute symbols
723 	     defined in a linker script.  */
724 	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
725 					    &link_info,
726 					    tree->name.name,
727 					    FALSE, FALSE, TRUE);
728 	  if (!(h != NULL
729 		&& (h->type == bfd_link_hash_defined
730 		    || h->type == bfd_link_hash_defweak)
731 		&& h->u.def.section == bfd_abs_section_ptr
732 		&& (def = symbol_defined (tree->name.name)) != NULL
733 		&& def->iteration == (lang_statement_iteration & 255)))
734 	    expld.assign_name = NULL;
735 	}
736       if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
737 	new_rel_from_abs (expld.dot);
738       else
739 	{
740 	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
741 					    &link_info,
742 					    tree->name.name,
743 					    TRUE, FALSE, TRUE);
744 	  if (!h)
745 	    einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
746 	  else if (h->type == bfd_link_hash_defined
747 		   || h->type == bfd_link_hash_defweak)
748 	    {
749 	      asection *output_section;
750 
751 	      output_section = h->u.def.section->output_section;
752 	      if (output_section == NULL)
753 		{
754 		  if (expld.phase <= lang_mark_phase_enum)
755 		    new_rel (h->u.def.value, h->u.def.section);
756 		  else
757 		    einfo (_("%X%S: unresolvable symbol `%s'"
758 			     " referenced in expression\n"),
759 			   tree, tree->name.name);
760 		}
761 	      else if (output_section == bfd_abs_section_ptr
762 		       && (expld.section != bfd_abs_section_ptr
763 			   || config.sane_expr))
764 		new_number (h->u.def.value + h->u.def.section->output_offset);
765 	      else
766 		new_rel (h->u.def.value + h->u.def.section->output_offset,
767 			 output_section);
768 	    }
769 	  else if (expld.phase == lang_final_phase_enum
770 		   || (expld.phase != lang_mark_phase_enum
771 		       && expld.assigning_to_dot))
772 	    einfo (_("%F%S: undefined symbol `%s'"
773 		     " referenced in expression\n"),
774 		   tree, tree->name.name);
775 	  else if (h->type == bfd_link_hash_new)
776 	    {
777 	      h->type = bfd_link_hash_undefined;
778 	      h->u.undef.abfd = NULL;
779 	      if (h->u.undef.next == NULL && h != link_info.hash->undefs_tail)
780 		bfd_link_add_undef (link_info.hash, h);
781 	    }
782 	  if (expld.assign_src == NULL)
783 	    expld.assign_src = h;
784 	  else
785 	    expld.assign_src = (struct bfd_link_hash_entry *) 0 - 1;
786 	}
787       break;
788 
789     case ADDR:
790       if (expld.phase != lang_first_phase_enum)
791 	{
792 	  lang_output_section_statement_type *os;
793 
794 	  os = lang_output_section_find (tree->name.name);
795 	  if (os == NULL)
796 	    {
797 	      if (expld.phase == lang_final_phase_enum)
798 		einfo (_("%F%S: undefined section `%s'"
799 			 " referenced in expression\n"),
800 		       tree, tree->name.name);
801 	    }
802 	  else if (os->processed_vma)
803 	    new_rel (0, os->bfd_section);
804 	}
805       break;
806 
807     case LOADADDR:
808       if (expld.phase != lang_first_phase_enum)
809 	{
810 	  lang_output_section_statement_type *os;
811 
812 	  os = lang_output_section_find (tree->name.name);
813 	  if (os == NULL)
814 	    {
815 	      if (expld.phase == lang_final_phase_enum)
816 		einfo (_("%F%S: undefined section `%s'"
817 			 " referenced in expression\n"),
818 		       tree, tree->name.name);
819 	    }
820 	  else if (os->processed_lma)
821 	    {
822 	      if (os->load_base == NULL)
823 		new_abs (os->bfd_section->lma);
824 	      else
825 		{
826 		  exp_fold_tree_1 (os->load_base);
827 		  if (expld.result.valid_p)
828 		    make_abs ();
829 		}
830 	    }
831 	}
832       break;
833 
834     case SIZEOF:
835     case ALIGNOF:
836       if (expld.phase != lang_first_phase_enum)
837 	{
838 	  lang_output_section_statement_type *os;
839 
840 	  os = lang_output_section_find (tree->name.name);
841 	  if (os == NULL)
842 	    {
843 	      if (expld.phase == lang_final_phase_enum)
844 		einfo (_("%F%S: undefined section `%s'"
845 			 " referenced in expression\n"),
846 		       tree, tree->name.name);
847 	      new_number (0);
848 	    }
849 	  else if (os->bfd_section != NULL)
850 	    {
851 	      bfd_vma val;
852 
853 	      if (tree->type.node_code == SIZEOF)
854 		val = (os->bfd_section->size
855 		       / bfd_octets_per_byte (link_info.output_bfd));
856 	      else
857 		val = (bfd_vma)1 << os->bfd_section->alignment_power;
858 
859 	      new_number (val);
860 	    }
861 	  else
862 	    new_number (0);
863 	}
864       break;
865 
866     case LENGTH:
867       {
868       if (expld.phase != lang_first_phase_enum)
869 	{
870 	  lang_memory_region_type *mem;
871 
872 	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
873 	  if (mem != NULL)
874 	    new_number (mem->length);
875 	  else
876 	    einfo (_("%F%S: undefined MEMORY region `%s'"
877 		     " referenced in expression\n"),
878 		   tree, tree->name.name);
879 	}
880       }
881       break;
882 
883     case ORIGIN:
884       if (expld.phase != lang_first_phase_enum)
885 	{
886 	  lang_memory_region_type *mem;
887 
888 	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
889 	  if (mem != NULL)
890 	    new_rel_from_abs (mem->origin);
891 	  else
892 	    einfo (_("%F%S: undefined MEMORY region `%s'"
893 		     " referenced in expression\n"),
894 		   tree, tree->name.name);
895 	}
896       break;
897 
898     case CONSTANT:
899       if (strcmp (tree->name.name, "MAXPAGESIZE") == 0)
900 	new_number (config.maxpagesize);
901       else if (strcmp (tree->name.name, "COMMONPAGESIZE") == 0)
902 	new_number (config.commonpagesize);
903       else
904 	einfo (_("%F%S: unknown constant `%s' referenced in expression\n"),
905 	       tree, tree->name.name);
906       break;
907 
908     default:
909       FAIL ();
910       break;
911     }
912 }
913 
914 /* Return true if TREE is '.'.  */
915 
916 static bfd_boolean
917 is_dot (const etree_type *tree)
918 {
919   return (tree->type.node_class == etree_name
920 	  && tree->type.node_code == NAME
921 	  && tree->name.name[0] == '.'
922 	  && tree->name.name[1] == 0);
923 }
924 
925 /* Return true if TREE is a constant equal to VAL.  */
926 
927 static bfd_boolean
928 is_value (const etree_type *tree, bfd_vma val)
929 {
930   return (tree->type.node_class == etree_value
931 	  && tree->value.value == val);
932 }
933 
934 /* Return true if TREE is an absolute symbol equal to VAL defined in
935    a linker script.  */
936 
937 static bfd_boolean
938 is_sym_value (const etree_type *tree, bfd_vma val)
939 {
940   struct bfd_link_hash_entry *h;
941   struct definedness_hash_entry *def;
942 
943   return (tree->type.node_class == etree_name
944 	  && tree->type.node_code == NAME
945 	  && (def = symbol_defined (tree->name.name)) != NULL
946 	  && def->iteration == (lang_statement_iteration & 255)
947 	  && (h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
948 						&link_info,
949 						tree->name.name,
950 						FALSE, FALSE, TRUE)) != NULL
951 	  && h->ldscript_def
952 	  && h->type == bfd_link_hash_defined
953 	  && h->u.def.section == bfd_abs_section_ptr
954 	  && h->u.def.value == val);
955 }
956 
957 /* Return true if TREE is ". != 0".  */
958 
959 static bfd_boolean
960 is_dot_ne_0 (const etree_type *tree)
961 {
962   return (tree->type.node_class == etree_binary
963 	  && tree->type.node_code == NE
964 	  && is_dot (tree->binary.lhs)
965 	  && is_value (tree->binary.rhs, 0));
966 }
967 
968 /* Return true if TREE is ". = . + 0" or ". = . + sym" where sym is an
969    absolute constant with value 0 defined in a linker script.  */
970 
971 static bfd_boolean
972 is_dot_plus_0 (const etree_type *tree)
973 {
974   return (tree->type.node_class == etree_binary
975 	  && tree->type.node_code == '+'
976 	  && is_dot (tree->binary.lhs)
977 	  && (is_value (tree->binary.rhs, 0)
978 	      || is_sym_value (tree->binary.rhs, 0)));
979 }
980 
981 /* Return true if TREE is "ALIGN (. != 0 ? some_expression : 1)".  */
982 
983 static bfd_boolean
984 is_align_conditional (const etree_type *tree)
985 {
986   if (tree->type.node_class == etree_unary
987       && tree->type.node_code == ALIGN_K)
988     {
989       tree = tree->unary.child;
990       return (tree->type.node_class == etree_trinary
991 	      && is_dot_ne_0 (tree->trinary.cond)
992 	      && is_value (tree->trinary.rhs, 1));
993     }
994   return FALSE;
995 }
996 
997 static void
998 exp_fold_tree_1 (etree_type *tree)
999 {
1000   if (tree == NULL)
1001     {
1002       memset (&expld.result, 0, sizeof (expld.result));
1003       return;
1004     }
1005 
1006   switch (tree->type.node_class)
1007     {
1008     case etree_value:
1009       if (expld.section == bfd_abs_section_ptr
1010 	  && !config.sane_expr)
1011 	new_abs (tree->value.value);
1012       else
1013 	new_number (tree->value.value);
1014       expld.result.str = tree->value.str;
1015       break;
1016 
1017     case etree_rel:
1018       if (expld.phase != lang_first_phase_enum)
1019 	{
1020 	  asection *output_section = tree->rel.section->output_section;
1021 	  new_rel (tree->rel.value + tree->rel.section->output_offset,
1022 		   output_section);
1023 	}
1024       else
1025 	memset (&expld.result, 0, sizeof (expld.result));
1026       break;
1027 
1028     case etree_assert:
1029       exp_fold_tree_1 (tree->assert_s.child);
1030       if (expld.phase == lang_final_phase_enum && !expld.result.value)
1031 	einfo ("%X%P: %s\n", tree->assert_s.message);
1032       break;
1033 
1034     case etree_unary:
1035       fold_unary (tree);
1036       break;
1037 
1038     case etree_binary:
1039       fold_binary (tree);
1040       break;
1041 
1042     case etree_trinary:
1043       fold_trinary (tree);
1044       break;
1045 
1046     case etree_assign:
1047     case etree_provide:
1048     case etree_provided:
1049       if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
1050 	{
1051 	  if (tree->type.node_class != etree_assign)
1052 	    einfo (_("%F%S can not PROVIDE assignment to"
1053 		     " location counter\n"), tree);
1054 	  if (expld.phase != lang_first_phase_enum)
1055 	    {
1056 	      /* Notify the folder that this is an assignment to dot.  */
1057 	      expld.assigning_to_dot = TRUE;
1058 	      exp_fold_tree_1 (tree->assign.src);
1059 	      expld.assigning_to_dot = FALSE;
1060 
1061 	      /* If we are assigning to dot inside an output section
1062 		 arrange to keep the section, except for certain
1063 		 expressions that evaluate to zero.  We ignore . = 0,
1064 		 . = . + 0, and . = ALIGN (. != 0 ? expr : 1).
1065 		 We can't ignore all expressions that evaluate to zero
1066 		 because an otherwise empty section might have padding
1067 		 added by an alignment expression that changes with
1068 		 relaxation.  Such a section might have zero size
1069 		 before relaxation and so be stripped incorrectly.  */
1070 	      if (expld.phase == lang_mark_phase_enum
1071 		  && expld.section != bfd_abs_section_ptr
1072 		  && expld.section != bfd_und_section_ptr
1073 		  && !(expld.result.valid_p
1074 		       && expld.result.value == 0
1075 		       && (is_value (tree->assign.src, 0)
1076 			   || is_sym_value (tree->assign.src, 0)
1077 			   || is_dot_plus_0 (tree->assign.src)
1078 			   || is_align_conditional (tree->assign.src))))
1079 		expld.section->flags |= SEC_KEEP;
1080 
1081 	      if (!expld.result.valid_p
1082 		  || expld.section == bfd_und_section_ptr)
1083 		{
1084 		  if (expld.phase != lang_mark_phase_enum)
1085 		    einfo (_("%F%S invalid assignment to"
1086 			     " location counter\n"), tree);
1087 		}
1088 	      else if (expld.dotp == NULL)
1089 		einfo (_("%F%S assignment to location counter"
1090 			 " invalid outside of SECTIONS\n"), tree);
1091 
1092 	      /* After allocation, assignment to dot should not be
1093 		 done inside an output section since allocation adds a
1094 		 padding statement that effectively duplicates the
1095 		 assignment.  */
1096 	      else if (expld.phase <= lang_allocating_phase_enum
1097 		       || expld.section == bfd_abs_section_ptr)
1098 		{
1099 		  bfd_vma nextdot;
1100 
1101 		  nextdot = expld.result.value;
1102 		  if (expld.result.section != NULL)
1103 		    nextdot += expld.result.section->vma;
1104 		  else
1105 		    nextdot += expld.section->vma;
1106 		  if (nextdot < expld.dot
1107 		      && expld.section != bfd_abs_section_ptr)
1108 		    einfo (_("%F%S cannot move location counter backwards"
1109 			     " (from %V to %V)\n"),
1110 			   tree, expld.dot, nextdot);
1111 		  else
1112 		    {
1113 		      expld.dot = nextdot;
1114 		      *expld.dotp = nextdot;
1115 		    }
1116 		}
1117 	    }
1118 	  else
1119 	    memset (&expld.result, 0, sizeof (expld.result));
1120 	}
1121       else
1122 	{
1123 	  struct bfd_link_hash_entry *h = NULL;
1124 
1125 	  if (tree->type.node_class == etree_provide)
1126 	    {
1127 	      h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
1128 					FALSE, FALSE, TRUE);
1129 	      if (h == NULL
1130 		  || !(h->type == bfd_link_hash_new
1131 		       || h->type == bfd_link_hash_undefined
1132 		       || h->type == bfd_link_hash_undefweak
1133 		       || h->linker_def))
1134 		{
1135 		  /* Do nothing.  The symbol was never referenced, or
1136 		     was defined in some object file.  Note that
1137 		     undefweak symbols are defined by PROVIDE.  This
1138 		     is to support glibc use of __rela_iplt_start and
1139 		     similar weak references.  */
1140 		  break;
1141 		}
1142 	    }
1143 
1144 	  expld.assign_name = tree->assign.dst;
1145 	  expld.assign_src = NULL;
1146 	  exp_fold_tree_1 (tree->assign.src);
1147 	  /* expld.assign_name remaining equal to tree->assign.dst
1148 	     below indicates the evaluation of tree->assign.src did
1149 	     not use the value of tree->assign.dst.  We don't allow
1150 	     self assignment until the final phase for two reasons:
1151 	     1) Expressions are evaluated multiple times.  With
1152 	     relaxation, the number of times may vary.
1153 	     2) Section relative symbol values cannot be correctly
1154 	     converted to absolute values, as is required by many
1155 	     expressions, until final section sizing is complete.  */
1156 	  if (expld.phase == lang_final_phase_enum
1157               || expld.assign_name != NULL)
1158 	    {
1159 	      if (tree->type.node_class == etree_provide)
1160 		tree->type.node_class = etree_provided;
1161 
1162 	      if (h == NULL)
1163 		{
1164 		  h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
1165 					    TRUE, FALSE, TRUE);
1166 		  if (h == NULL)
1167 		    einfo (_("%P%F:%s: hash creation failed\n"),
1168 			   tree->assign.dst);
1169 		}
1170 
1171               /* If the expression is not valid then fake a zero value.  In
1172                  the final phase any errors will already have been raised,
1173                  in earlier phases we want to create this definition so
1174                  that it can be seen by other expressions.  */
1175               if (!expld.result.valid_p
1176                   && h->type == bfd_link_hash_new)
1177                 {
1178                   expld.result.value = 0;
1179                   expld.result.section = NULL;
1180                   expld.result.valid_p = TRUE;
1181                 }
1182 
1183 	      if (expld.result.valid_p)
1184 		{
1185 		  if (expld.result.section == NULL)
1186 		    expld.result.section = expld.section;
1187 		  if (!update_definedness (tree->assign.dst, h) && 0)
1188 		    {
1189 		      /* Symbol was already defined.  For now this error
1190 			 is disabled because it causes failures in the ld
1191 			 testsuite: ld-elf/var1, ld-scripts/defined5, and
1192 			 ld-scripts/pr14962.  Some of these no doubt
1193 			 reflect scripts used in the wild.  */
1194 		      (*link_info.callbacks->multiple_definition)
1195 			(&link_info, h, link_info.output_bfd,
1196 			 expld.result.section, expld.result.value);
1197 		    }
1198 		  h->type = bfd_link_hash_defined;
1199 		  h->u.def.value = expld.result.value;
1200 		  h->u.def.section = expld.result.section;
1201 		  h->linker_def = ! tree->assign.type.lineno;
1202 		  h->ldscript_def = 1;
1203 
1204 		  /* Copy the symbol type if this is an expression only
1205 		     referencing a single symbol.  (If the expression
1206 		     contains ternary conditions, ignoring symbols on
1207 		     false branches.)  */
1208 		  if (expld.assign_src != NULL
1209 		      && (expld.assign_src
1210 			  != (struct bfd_link_hash_entry *) 0 - 1))
1211 		    bfd_copy_link_hash_symbol_type (link_info.output_bfd, h,
1212 						    expld.assign_src);
1213 		}
1214 	    }
1215 	  expld.assign_name = NULL;
1216 	}
1217       break;
1218 
1219     case etree_name:
1220       fold_name (tree);
1221       break;
1222 
1223     default:
1224       FAIL ();
1225       memset (&expld.result, 0, sizeof (expld.result));
1226       break;
1227     }
1228 }
1229 
1230 void
1231 exp_fold_tree (etree_type *tree, asection *current_section, bfd_vma *dotp)
1232 {
1233   expld.rel_from_abs = FALSE;
1234   expld.dot = *dotp;
1235   expld.dotp = dotp;
1236   expld.section = current_section;
1237   exp_fold_tree_1 (tree);
1238 }
1239 
1240 void
1241 exp_fold_tree_no_dot (etree_type *tree)
1242 {
1243   expld.rel_from_abs = FALSE;
1244   expld.dot = 0;
1245   expld.dotp = NULL;
1246   expld.section = bfd_abs_section_ptr;
1247   exp_fold_tree_1 (tree);
1248 }
1249 
1250 static void
1251 exp_value_fold (etree_type *tree)
1252 {
1253   exp_fold_tree_no_dot (tree);
1254   if (expld.result.valid_p)
1255     {
1256       tree->type.node_code = INT;
1257       tree->value.value = expld.result.value;
1258       tree->value.str = NULL;
1259       tree->type.node_class = etree_value;
1260     }
1261 }
1262 
1263 #define MAX(a, b) ((a) > (b) ? (a) : (b))
1264 
1265 etree_type *
1266 exp_binop (int code, etree_type *lhs, etree_type *rhs)
1267 {
1268   etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->binary),
1269 						      sizeof (new_e->value)));
1270   new_e->type.node_code = code;
1271   new_e->type.filename = lhs->type.filename;
1272   new_e->type.lineno = lhs->type.lineno;
1273   new_e->binary.lhs = lhs;
1274   new_e->binary.rhs = rhs;
1275   new_e->type.node_class = etree_binary;
1276   if (lhs->type.node_class == etree_value
1277       && rhs->type.node_class == etree_value
1278       && code != ALIGN_K
1279       && code != DATA_SEGMENT_ALIGN
1280       && code != DATA_SEGMENT_RELRO_END)
1281     exp_value_fold (new_e);
1282   return new_e;
1283 }
1284 
1285 etree_type *
1286 exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
1287 {
1288   etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->trinary),
1289 						      sizeof (new_e->value)));
1290   new_e->type.node_code = code;
1291   new_e->type.filename = cond->type.filename;
1292   new_e->type.lineno = cond->type.lineno;
1293   new_e->trinary.lhs = lhs;
1294   new_e->trinary.cond = cond;
1295   new_e->trinary.rhs = rhs;
1296   new_e->type.node_class = etree_trinary;
1297   if (cond->type.node_class == etree_value
1298       && lhs->type.node_class == etree_value
1299       && rhs->type.node_class == etree_value)
1300     exp_value_fold (new_e);
1301   return new_e;
1302 }
1303 
1304 etree_type *
1305 exp_unop (int code, etree_type *child)
1306 {
1307   etree_type *new_e = (etree_type *) stat_alloc (MAX (sizeof (new_e->unary),
1308 						      sizeof (new_e->value)));
1309   new_e->unary.type.node_code = code;
1310   new_e->unary.type.filename = child->type.filename;
1311   new_e->unary.type.lineno = child->type.lineno;
1312   new_e->unary.child = child;
1313   new_e->unary.type.node_class = etree_unary;
1314   if (child->type.node_class == etree_value
1315       && code != ALIGN_K
1316       && code != ABSOLUTE
1317       && code != NEXT
1318       && code != DATA_SEGMENT_END)
1319     exp_value_fold (new_e);
1320   return new_e;
1321 }
1322 
1323 etree_type *
1324 exp_nameop (int code, const char *name)
1325 {
1326   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->name));
1327 
1328   new_e->name.type.node_code = code;
1329   new_e->name.type.filename = ldlex_filename ();
1330   new_e->name.type.lineno = lineno;
1331   new_e->name.name = name;
1332   new_e->name.type.node_class = etree_name;
1333   return new_e;
1334 
1335 }
1336 
1337 static etree_type *
1338 exp_assop (const char *dst,
1339 	   etree_type *src,
1340 	   enum node_tree_enum class,
1341 	   bfd_boolean hidden)
1342 {
1343   etree_type *n;
1344 
1345   n = (etree_type *) stat_alloc (sizeof (n->assign));
1346   n->assign.type.node_code = '=';
1347   n->assign.type.filename = src->type.filename;
1348   n->assign.type.lineno = src->type.lineno;
1349   n->assign.type.node_class = class;
1350   n->assign.src = src;
1351   n->assign.dst = dst;
1352   n->assign.hidden = hidden;
1353   return n;
1354 }
1355 
1356 /* Handle linker script assignments and HIDDEN.  */
1357 
1358 etree_type *
1359 exp_assign (const char *dst, etree_type *src, bfd_boolean hidden)
1360 {
1361   return exp_assop (dst, src, etree_assign, hidden);
1362 }
1363 
1364 /* Handle --defsym command-line option.  */
1365 
1366 etree_type *
1367 exp_defsym (const char *dst, etree_type *src)
1368 {
1369   return exp_assop (dst, src, etree_assign, FALSE);
1370 }
1371 
1372 /* Handle PROVIDE.  */
1373 
1374 etree_type *
1375 exp_provide (const char *dst, etree_type *src, bfd_boolean hidden)
1376 {
1377   return exp_assop (dst, src, etree_provide, hidden);
1378 }
1379 
1380 /* Handle ASSERT.  */
1381 
1382 etree_type *
1383 exp_assert (etree_type *exp, const char *message)
1384 {
1385   etree_type *n;
1386 
1387   n = (etree_type *) stat_alloc (sizeof (n->assert_s));
1388   n->assert_s.type.node_code = '!';
1389   n->assert_s.type.filename = exp->type.filename;
1390   n->assert_s.type.lineno = exp->type.lineno;
1391   n->assert_s.type.node_class = etree_assert;
1392   n->assert_s.child = exp;
1393   n->assert_s.message = message;
1394   return n;
1395 }
1396 
1397 void
1398 exp_print_tree (etree_type *tree)
1399 {
1400   bfd_boolean function_like;
1401 
1402   if (config.map_file == NULL)
1403     config.map_file = stderr;
1404 
1405   if (tree == NULL)
1406     {
1407       minfo ("NULL TREE\n");
1408       return;
1409     }
1410 
1411   switch (tree->type.node_class)
1412     {
1413     case etree_value:
1414       minfo ("0x%v", tree->value.value);
1415       return;
1416     case etree_rel:
1417       if (tree->rel.section->owner != NULL)
1418 	minfo ("%B:", tree->rel.section->owner);
1419       minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
1420       return;
1421     case etree_assign:
1422       fputs (tree->assign.dst, config.map_file);
1423       exp_print_token (tree->type.node_code, TRUE);
1424       exp_print_tree (tree->assign.src);
1425       break;
1426     case etree_provide:
1427     case etree_provided:
1428       fprintf (config.map_file, "PROVIDE (%s = ", tree->assign.dst);
1429       exp_print_tree (tree->assign.src);
1430       fputc (')', config.map_file);
1431       break;
1432     case etree_binary:
1433       function_like = FALSE;
1434       switch (tree->type.node_code)
1435 	{
1436 	case MAX_K:
1437 	case MIN_K:
1438 	case ALIGN_K:
1439 	case DATA_SEGMENT_ALIGN:
1440 	case DATA_SEGMENT_RELRO_END:
1441 	  function_like = TRUE;
1442 	  break;
1443 	case SEGMENT_START:
1444 	  /* Special handling because arguments are in reverse order and
1445 	     the segment name is quoted.  */
1446 	  exp_print_token (tree->type.node_code, FALSE);
1447 	  fputs (" (\"", config.map_file);
1448 	  exp_print_tree (tree->binary.rhs);
1449 	  fputs ("\", ", config.map_file);
1450 	  exp_print_tree (tree->binary.lhs);
1451 	  fputc (')', config.map_file);
1452 	  return;
1453 	}
1454       if (function_like)
1455 	{
1456 	  exp_print_token (tree->type.node_code, FALSE);
1457 	  fputc (' ', config.map_file);
1458 	}
1459       fputc ('(', config.map_file);
1460       exp_print_tree (tree->binary.lhs);
1461       if (function_like)
1462 	fprintf (config.map_file, ", ");
1463       else
1464 	exp_print_token (tree->type.node_code, TRUE);
1465       exp_print_tree (tree->binary.rhs);
1466       fputc (')', config.map_file);
1467       break;
1468     case etree_trinary:
1469       exp_print_tree (tree->trinary.cond);
1470       fputc ('?', config.map_file);
1471       exp_print_tree (tree->trinary.lhs);
1472       fputc (':', config.map_file);
1473       exp_print_tree (tree->trinary.rhs);
1474       break;
1475     case etree_unary:
1476       exp_print_token (tree->unary.type.node_code, FALSE);
1477       if (tree->unary.child)
1478 	{
1479 	  fprintf (config.map_file, " (");
1480 	  exp_print_tree (tree->unary.child);
1481 	  fputc (')', config.map_file);
1482 	}
1483       break;
1484 
1485     case etree_assert:
1486       fprintf (config.map_file, "ASSERT (");
1487       exp_print_tree (tree->assert_s.child);
1488       fprintf (config.map_file, ", %s)", tree->assert_s.message);
1489       break;
1490 
1491     case etree_name:
1492       if (tree->type.node_code == NAME)
1493 	fputs (tree->name.name, config.map_file);
1494       else
1495 	{
1496 	  exp_print_token (tree->type.node_code, FALSE);
1497 	  if (tree->name.name)
1498 	    fprintf (config.map_file, " (%s)", tree->name.name);
1499 	}
1500       break;
1501     default:
1502       FAIL ();
1503       break;
1504     }
1505 }
1506 
1507 bfd_vma
1508 exp_get_vma (etree_type *tree, bfd_vma def, char *name)
1509 {
1510   if (tree != NULL)
1511     {
1512       exp_fold_tree_no_dot (tree);
1513       if (expld.result.valid_p)
1514 	return expld.result.value;
1515       else if (name != NULL && expld.phase != lang_mark_phase_enum)
1516 	einfo (_("%F%S: nonconstant expression for %s\n"),
1517 	       tree, name);
1518     }
1519   return def;
1520 }
1521 
1522 int
1523 exp_get_value_int (etree_type *tree, int def, char *name)
1524 {
1525   return exp_get_vma (tree, def, name);
1526 }
1527 
1528 fill_type *
1529 exp_get_fill (etree_type *tree, fill_type *def, char *name)
1530 {
1531   fill_type *fill;
1532   size_t len;
1533   unsigned int val;
1534 
1535   if (tree == NULL)
1536     return def;
1537 
1538   exp_fold_tree_no_dot (tree);
1539   if (!expld.result.valid_p)
1540     {
1541       if (name != NULL && expld.phase != lang_mark_phase_enum)
1542 	einfo (_("%F%S: nonconstant expression for %s\n"),
1543 	       tree, name);
1544       return def;
1545     }
1546 
1547   if (expld.result.str != NULL && (len = strlen (expld.result.str)) != 0)
1548     {
1549       unsigned char *dst;
1550       unsigned char *s;
1551       fill = (fill_type *) xmalloc ((len + 1) / 2 + sizeof (*fill) - 1);
1552       fill->size = (len + 1) / 2;
1553       dst = fill->data;
1554       s = (unsigned char *) expld.result.str;
1555       val = 0;
1556       do
1557 	{
1558 	  unsigned int digit;
1559 
1560 	  digit = *s++ - '0';
1561 	  if (digit > 9)
1562 	    digit = (digit - 'A' + '0' + 10) & 0xf;
1563 	  val <<= 4;
1564 	  val += digit;
1565 	  --len;
1566 	  if ((len & 1) == 0)
1567 	    {
1568 	      *dst++ = val;
1569 	      val = 0;
1570 	    }
1571 	}
1572       while (len != 0);
1573     }
1574   else
1575     {
1576       fill = (fill_type *) xmalloc (4 + sizeof (*fill) - 1);
1577       val = expld.result.value;
1578       fill->data[0] = (val >> 24) & 0xff;
1579       fill->data[1] = (val >> 16) & 0xff;
1580       fill->data[2] = (val >>  8) & 0xff;
1581       fill->data[3] = (val >>  0) & 0xff;
1582       fill->size = 4;
1583     }
1584   return fill;
1585 }
1586 
1587 bfd_vma
1588 exp_get_abs_int (etree_type *tree, int def, char *name)
1589 {
1590   if (tree != NULL)
1591     {
1592       exp_fold_tree_no_dot (tree);
1593 
1594       if (expld.result.valid_p)
1595 	{
1596 	  if (expld.result.section != NULL)
1597 	    expld.result.value += expld.result.section->vma;
1598 	  return expld.result.value;
1599 	}
1600       else if (name != NULL && expld.phase != lang_mark_phase_enum)
1601 	{
1602 	  einfo (_("%F%S: nonconstant expression for %s\n"),
1603 		 tree, name);
1604 	}
1605     }
1606   return def;
1607 }
1608 
1609 static bfd_vma
1610 align_n (bfd_vma value, bfd_vma align)
1611 {
1612   if (align <= 1)
1613     return value;
1614 
1615   value = (value + align - 1) / align;
1616   return value * align;
1617 }
1618 
1619 void
1620 ldexp_init (void)
1621 {
1622   /* The value "13" is ad-hoc, somewhat related to the expected number of
1623      assignments in a linker script.  */
1624   if (!bfd_hash_table_init_n (&definedness_table,
1625 			      definedness_newfunc,
1626 			      sizeof (struct definedness_hash_entry),
1627 			      13))
1628     einfo (_("%P%F: can not create hash table: %E\n"));
1629 }
1630 
1631 /* Convert absolute symbols defined by a script from "dot" (also
1632    SEGMENT_START or ORIGIN) outside of an output section statement,
1633    to section relative.  */
1634 
1635 static bfd_boolean
1636 set_sym_sections (struct bfd_hash_entry *bh, void *inf ATTRIBUTE_UNUSED)
1637 {
1638   struct definedness_hash_entry *def = (struct definedness_hash_entry *) bh;
1639   if (def->final_sec != bfd_abs_section_ptr)
1640     {
1641       struct bfd_link_hash_entry *h;
1642       h = bfd_link_hash_lookup (link_info.hash, bh->string,
1643 				FALSE, FALSE, TRUE);
1644       if (h != NULL
1645 	  && h->type == bfd_link_hash_defined
1646 	  && h->u.def.section == bfd_abs_section_ptr)
1647 	{
1648 	  h->u.def.value -= def->final_sec->vma;
1649 	  h->u.def.section = def->final_sec;
1650 	}
1651     }
1652   return TRUE;
1653 }
1654 
1655 void
1656 ldexp_finalize_syms (void)
1657 {
1658   bfd_hash_traverse (&definedness_table, set_sym_sections, NULL);
1659 }
1660 
1661 void
1662 ldexp_finish (void)
1663 {
1664   bfd_hash_table_free (&definedness_table);
1665 }
1666