xref: /dragonfly/contrib/binutils-2.27/ld/ldexp.c (revision ae24b5e0)
1 /* This module handles expression trees.
2    Copyright (C) 1991-2016 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   /* Symbol was defined by an object file.  */
64   unsigned int by_object : 1;
65 
66   /* Symbols was defined by a script.  */
67   unsigned int by_script : 1;
68 
69   /* Low bit of iteration count.  Symbols with matching iteration have
70      been defined in this pass over the script.  */
71   unsigned int iteration : 1;
72 };
73 
74 static struct bfd_hash_table definedness_table;
75 
76 /* Print the string representation of the given token.  Surround it
77    with spaces if INFIX_P is TRUE.  */
78 
79 static void
80 exp_print_token (token_code_type code, int infix_p)
81 {
82   static const struct
83   {
84     token_code_type code;
85     const char *name;
86   }
87   table[] =
88   {
89     { INT, "int" },
90     { NAME, "NAME" },
91     { PLUSEQ, "+=" },
92     { MINUSEQ, "-=" },
93     { MULTEQ, "*=" },
94     { DIVEQ, "/=" },
95     { LSHIFTEQ, "<<=" },
96     { RSHIFTEQ, ">>=" },
97     { ANDEQ, "&=" },
98     { OREQ, "|=" },
99     { OROR, "||" },
100     { ANDAND, "&&" },
101     { EQ, "==" },
102     { NE, "!=" },
103     { LE, "<=" },
104     { GE, ">=" },
105     { LSHIFT, "<<" },
106     { RSHIFT, ">>" },
107     { LOG2CEIL, "LOG2CEIL" },
108     { ALIGN_K, "ALIGN" },
109     { BLOCK, "BLOCK" },
110     { QUAD, "QUAD" },
111     { SQUAD, "SQUAD" },
112     { LONG, "LONG" },
113     { SHORT, "SHORT" },
114     { BYTE, "BYTE" },
115     { SECTIONS, "SECTIONS" },
116     { SIZEOF_HEADERS, "SIZEOF_HEADERS" },
117     { MEMORY, "MEMORY" },
118     { DEFINED, "DEFINED" },
119     { TARGET_K, "TARGET" },
120     { SEARCH_DIR, "SEARCH_DIR" },
121     { MAP, "MAP" },
122     { ENTRY, "ENTRY" },
123     { NEXT, "NEXT" },
124     { ALIGNOF, "ALIGNOF" },
125     { SIZEOF, "SIZEOF" },
126     { ADDR, "ADDR" },
127     { LOADADDR, "LOADADDR" },
128     { CONSTANT, "CONSTANT" },
129     { ABSOLUTE, "ABSOLUTE" },
130     { MAX_K, "MAX" },
131     { MIN_K, "MIN" },
132     { ASSERT_K, "ASSERT" },
133     { REL, "relocatable" },
134     { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
135     { DATA_SEGMENT_RELRO_END, "DATA_SEGMENT_RELRO_END" },
136     { DATA_SEGMENT_END, "DATA_SEGMENT_END" },
137     { ORIGIN, "ORIGIN" },
138     { LENGTH, "LENGTH" },
139     { SEGMENT_START, "SEGMENT_START" }
140   };
141   unsigned int idx;
142 
143   for (idx = 0; idx < ARRAY_SIZE (table); idx++)
144     if (table[idx].code == code)
145       break;
146 
147   if (infix_p)
148     fputc (' ', config.map_file);
149 
150   if (idx < ARRAY_SIZE (table))
151     fputs (table[idx].name, config.map_file);
152   else if (code < 127)
153     fputc (code, config.map_file);
154   else
155     fprintf (config.map_file, "<code %d>", code);
156 
157   if (infix_p)
158     fputc (' ', config.map_file);
159 }
160 
161 static void
162 make_log2ceil (void)
163 {
164   bfd_vma value = expld.result.value;
165   bfd_vma result = -1;
166   bfd_boolean round_up = FALSE;
167 
168   do
169     {
170       result++;
171       /* If more than one bit is set in the value we will need to round up.  */
172       if ((value > 1) && (value & 1))
173 	round_up = TRUE;
174     }
175   while (value >>= 1);
176 
177   if (round_up)
178     result += 1;
179   expld.result.section = NULL;
180   expld.result.value = result;
181 }
182 
183 static void
184 make_abs (void)
185 {
186   if (expld.result.section != NULL)
187     expld.result.value += expld.result.section->vma;
188   expld.result.section = bfd_abs_section_ptr;
189   expld.rel_from_abs = FALSE;
190 }
191 
192 static void
193 new_abs (bfd_vma value)
194 {
195   expld.result.valid_p = TRUE;
196   expld.result.section = bfd_abs_section_ptr;
197   expld.result.value = value;
198   expld.result.str = NULL;
199 }
200 
201 etree_type *
202 exp_intop (bfd_vma value)
203 {
204   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
205   new_e->type.node_code = INT;
206   new_e->type.filename = ldlex_filename ();
207   new_e->type.lineno = lineno;
208   new_e->value.value = value;
209   new_e->value.str = NULL;
210   new_e->type.node_class = etree_value;
211   return new_e;
212 }
213 
214 etree_type *
215 exp_bigintop (bfd_vma value, char *str)
216 {
217   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
218   new_e->type.node_code = INT;
219   new_e->type.filename = ldlex_filename ();
220   new_e->type.lineno = lineno;
221   new_e->value.value = value;
222   new_e->value.str = str;
223   new_e->type.node_class = etree_value;
224   return new_e;
225 }
226 
227 /* Build an expression representing an unnamed relocatable value.  */
228 
229 etree_type *
230 exp_relop (asection *section, bfd_vma value)
231 {
232   etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->rel));
233   new_e->type.node_code = REL;
234   new_e->type.filename = ldlex_filename ();
235   new_e->type.lineno = lineno;
236   new_e->type.node_class = etree_rel;
237   new_e->rel.section = section;
238   new_e->rel.value = value;
239   return new_e;
240 }
241 
242 static void
243 new_number (bfd_vma value)
244 {
245   expld.result.valid_p = TRUE;
246   expld.result.value = value;
247   expld.result.str = NULL;
248   expld.result.section = NULL;
249 }
250 
251 static void
252 new_rel (bfd_vma value, asection *section)
253 {
254   expld.result.valid_p = TRUE;
255   expld.result.value = value;
256   expld.result.str = NULL;
257   expld.result.section = section;
258 }
259 
260 static void
261 new_rel_from_abs (bfd_vma value)
262 {
263   asection *s = expld.section;
264 
265   expld.rel_from_abs = TRUE;
266   expld.result.valid_p = TRUE;
267   expld.result.value = value - s->vma;
268   expld.result.str = NULL;
269   expld.result.section = s;
270 }
271 
272 /* New-function for the definedness hash table.  */
273 
274 static struct bfd_hash_entry *
275 definedness_newfunc (struct bfd_hash_entry *entry,
276 		     struct bfd_hash_table *table ATTRIBUTE_UNUSED,
277 		     const char *name ATTRIBUTE_UNUSED)
278 {
279   struct definedness_hash_entry *ret = (struct definedness_hash_entry *) entry;
280 
281   if (ret == NULL)
282     ret = (struct definedness_hash_entry *)
283       bfd_hash_allocate (table, sizeof (struct definedness_hash_entry));
284 
285   if (ret == NULL)
286     einfo (_("%P%F: bfd_hash_allocate failed creating symbol %s\n"), name);
287 
288   ret->by_object = 0;
289   ret->by_script = 0;
290   ret->iteration = 0;
291   return &ret->root;
292 }
293 
294 /* Called during processing of linker script script expressions.
295    For symbols assigned in a linker script, return a struct describing
296    where the symbol is defined relative to the current expression,
297    otherwise return NULL.  */
298 
299 static struct definedness_hash_entry *
300 symbol_defined (const char *name)
301 {
302   return ((struct definedness_hash_entry *)
303 	  bfd_hash_lookup (&definedness_table, name, FALSE, FALSE));
304 }
305 
306 /* Update the definedness state of NAME.  Return FALSE if script symbol
307    is multiply defining a strong symbol in an object.  */
308 
309 static bfd_boolean
310 update_definedness (const char *name, struct bfd_link_hash_entry *h)
311 {
312   bfd_boolean ret;
313   struct definedness_hash_entry *defentry
314     = (struct definedness_hash_entry *)
315     bfd_hash_lookup (&definedness_table, name, TRUE, FALSE);
316 
317   if (defentry == NULL)
318     einfo (_("%P%F: bfd_hash_lookup failed creating symbol %s\n"), name);
319 
320   /* If the symbol was already defined, and not by a script, then it
321      must be defined by an object file or by the linker target code.  */
322   ret = TRUE;
323   if (!defentry->by_script
324       && (h->type == bfd_link_hash_defined
325 	  || h->type == bfd_link_hash_defweak
326 	  || h->type == bfd_link_hash_common))
327     {
328       defentry->by_object = 1;
329       if (h->type == bfd_link_hash_defined
330 	  && h->u.def.section->output_section != NULL
331 	  && !h->linker_def)
332 	ret = FALSE;
333     }
334 
335   defentry->by_script = 1;
336   defentry->iteration = lang_statement_iteration;
337   defentry->final_sec = bfd_abs_section_ptr;
338   if (expld.phase == lang_final_phase_enum
339       && expld.rel_from_abs
340       && expld.result.section == bfd_abs_section_ptr)
341     defentry->final_sec = section_for_dot ();
342   return ret;
343 }
344 
345 static void
346 fold_unary (etree_type *tree)
347 {
348   exp_fold_tree_1 (tree->unary.child);
349   if (expld.result.valid_p)
350     {
351       switch (tree->type.node_code)
352 	{
353 	case ALIGN_K:
354 	  if (expld.phase != lang_first_phase_enum)
355 	    new_rel_from_abs (align_n (expld.dot, expld.result.value));
356 	  else
357 	    expld.result.valid_p = FALSE;
358 	  break;
359 
360 	case ABSOLUTE:
361 	  make_abs ();
362 	  break;
363 
364 	case LOG2CEIL:
365 	  make_log2ceil ();
366 	  break;
367 
368 	case '~':
369 	  expld.result.value = ~expld.result.value;
370 	  break;
371 
372 	case '!':
373 	  expld.result.value = !expld.result.value;
374 	  break;
375 
376 	case '-':
377 	  expld.result.value = -expld.result.value;
378 	  break;
379 
380 	case NEXT:
381 	  /* Return next place aligned to value.  */
382 	  if (expld.phase != lang_first_phase_enum)
383 	    {
384 	      make_abs ();
385 	      expld.result.value = align_n (expld.dot, expld.result.value);
386 	    }
387 	  else
388 	    expld.result.valid_p = FALSE;
389 	  break;
390 
391 	case DATA_SEGMENT_END:
392 	  if (expld.phase == lang_first_phase_enum
393 	      || expld.section != bfd_abs_section_ptr)
394 	    {
395 	      expld.result.valid_p = FALSE;
396 	    }
397 	  else if (expld.dataseg.phase == exp_dataseg_align_seen
398 		   || expld.dataseg.phase == exp_dataseg_relro_seen)
399 	    {
400 	      expld.dataseg.phase = exp_dataseg_end_seen;
401 	      expld.dataseg.end = expld.result.value;
402 	    }
403 	  else if (expld.dataseg.phase == exp_dataseg_done
404 		   || expld.dataseg.phase == exp_dataseg_adjust
405 		   || expld.dataseg.phase == exp_dataseg_relro_adjust)
406 	    {
407 	      /* OK.  */
408 	    }
409 	  else
410 	    expld.result.valid_p = FALSE;
411 	  break;
412 
413 	default:
414 	  FAIL ();
415 	  break;
416 	}
417     }
418 }
419 
420 static void
421 fold_binary (etree_type *tree)
422 {
423   etree_value_type lhs;
424   exp_fold_tree_1 (tree->binary.lhs);
425 
426   /* The SEGMENT_START operator is special because its first
427      operand is a string, not the name of a symbol.  Note that the
428      operands have been swapped, so binary.lhs is second (default)
429      operand, binary.rhs is first operand.  */
430   if (expld.result.valid_p && tree->type.node_code == SEGMENT_START)
431     {
432       const char *segment_name;
433       segment_type *seg;
434 
435       /* Check to see if the user has overridden the default
436 	 value.  */
437       segment_name = tree->binary.rhs->name.name;
438       for (seg = segments; seg; seg = seg->next)
439 	if (strcmp (seg->name, segment_name) == 0)
440 	  {
441 	    if (!seg->used
442 		&& config.magic_demand_paged
443 		&& (seg->value % config.maxpagesize) != 0)
444 	      einfo (_("%P: warning: address of `%s' "
445 		       "isn't multiple of maximum page size\n"),
446 		     segment_name);
447 	    seg->used = TRUE;
448 	    new_rel_from_abs (seg->value);
449 	    break;
450 	  }
451       return;
452     }
453 
454   lhs = expld.result;
455   exp_fold_tree_1 (tree->binary.rhs);
456   expld.result.valid_p &= lhs.valid_p;
457 
458   if (expld.result.valid_p)
459     {
460       if (lhs.section != expld.result.section)
461 	{
462 	  /* If the values are from different sections, and neither is
463 	     just a number, make both the source arguments absolute.  */
464 	  if (expld.result.section != NULL
465 	      && lhs.section != NULL)
466 	    {
467 	      make_abs ();
468 	      lhs.value += lhs.section->vma;
469 	      lhs.section = bfd_abs_section_ptr;
470 	    }
471 
472 	  /* If the rhs is just a number, keep the lhs section.  */
473 	  else if (expld.result.section == NULL)
474 	    {
475 	      expld.result.section = lhs.section;
476 	      /* Make this NULL so that we know one of the operands
477 		 was just a number, for later tests.  */
478 	      lhs.section = NULL;
479 	    }
480 	}
481       /* At this point we know that both operands have the same
482 	 section, or at least one of them is a plain number.  */
483 
484       switch (tree->type.node_code)
485 	{
486 	  /* Arithmetic operators, bitwise AND, bitwise OR and XOR
487 	     keep the section of one of their operands only when the
488 	     other operand is a plain number.  Losing the section when
489 	     operating on two symbols, ie. a result of a plain number,
490 	     is required for subtraction and XOR.  It's justifiable
491 	     for the other operations on the grounds that adding,
492 	     multiplying etc. two section relative values does not
493 	     really make sense unless they are just treated as
494 	     numbers.
495 	     The same argument could be made for many expressions
496 	     involving one symbol and a number.  For example,
497 	     "1 << x" and "100 / x" probably should not be given the
498 	     section of x.  The trouble is that if we fuss about such
499 	     things the rules become complex and it is onerous to
500 	     document ld expression evaluation.  */
501 #define BOP(x, y) \
502 	case x:							\
503 	  expld.result.value = lhs.value y expld.result.value;	\
504 	  if (expld.result.section == lhs.section)		\
505 	    expld.result.section = NULL;			\
506 	  break;
507 
508 	  /* Comparison operators, logical AND, and logical OR always
509 	     return a plain number.  */
510 #define BOPN(x, y) \
511 	case x:							\
512 	  expld.result.value = lhs.value y expld.result.value;	\
513 	  expld.result.section = NULL;				\
514 	  break;
515 
516 	  BOP ('+', +);
517 	  BOP ('*', *);
518 	  BOP ('-', -);
519 	  BOP (LSHIFT, <<);
520 	  BOP (RSHIFT, >>);
521 	  BOP ('&', &);
522 	  BOP ('^', ^);
523 	  BOP ('|', |);
524 	  BOPN (EQ, ==);
525 	  BOPN (NE, !=);
526 	  BOPN ('<', <);
527 	  BOPN ('>', >);
528 	  BOPN (LE, <=);
529 	  BOPN (GE, >=);
530 	  BOPN (ANDAND, &&);
531 	  BOPN (OROR, ||);
532 
533 	case '%':
534 	  if (expld.result.value != 0)
535 	    expld.result.value = ((bfd_signed_vma) lhs.value
536 				  % (bfd_signed_vma) expld.result.value);
537 	  else if (expld.phase != lang_mark_phase_enum)
538 	    einfo (_("%F%S %% by zero\n"), tree->binary.rhs);
539 	  if (expld.result.section == lhs.section)
540 	    expld.result.section = NULL;
541 	  break;
542 
543 	case '/':
544 	  if (expld.result.value != 0)
545 	    expld.result.value = ((bfd_signed_vma) lhs.value
546 				  / (bfd_signed_vma) expld.result.value);
547 	  else if (expld.phase != lang_mark_phase_enum)
548 	    einfo (_("%F%S / by zero\n"), tree->binary.rhs);
549 	  if (expld.result.section == lhs.section)
550 	    expld.result.section = NULL;
551 	  break;
552 
553 	case MAX_K:
554 	  if (lhs.value > expld.result.value)
555 	    expld.result.value = lhs.value;
556 	  break;
557 
558 	case MIN_K:
559 	  if (lhs.value < expld.result.value)
560 	    expld.result.value = lhs.value;
561 	  break;
562 
563 	case ALIGN_K:
564 	  expld.result.value = align_n (lhs.value, expld.result.value);
565 	  break;
566 
567 	case DATA_SEGMENT_ALIGN:
568 	  expld.dataseg.relro = exp_dataseg_relro_start;
569 	  if (expld.phase == lang_first_phase_enum
570 	      || expld.section != bfd_abs_section_ptr)
571 	    expld.result.valid_p = FALSE;
572 	  else
573 	    {
574 	      bfd_vma maxpage = lhs.value;
575 	      bfd_vma commonpage = expld.result.value;
576 
577 	      expld.result.value = align_n (expld.dot, maxpage);
578 	      if (expld.dataseg.phase == exp_dataseg_relro_adjust)
579 		expld.result.value = expld.dataseg.base;
580 	      else if (expld.dataseg.phase == exp_dataseg_adjust)
581 		{
582 		  if (commonpage < maxpage)
583 		    expld.result.value += ((expld.dot + commonpage - 1)
584 					   & (maxpage - commonpage));
585 		}
586 	      else
587 		{
588 		  expld.result.value += expld.dot & (maxpage - 1);
589 		  if (expld.dataseg.phase == exp_dataseg_done)
590 		    {
591 		      /* OK.  */
592 		    }
593 		  else if (expld.dataseg.phase == exp_dataseg_none)
594 		    {
595 		      expld.dataseg.phase = exp_dataseg_align_seen;
596 		      expld.dataseg.base = expld.result.value;
597 		      expld.dataseg.pagesize = commonpage;
598 		      expld.dataseg.maxpagesize = maxpage;
599 		      expld.dataseg.relro_end = 0;
600 		    }
601 		  else
602 		    expld.result.valid_p = FALSE;
603 		}
604 	    }
605 	  break;
606 
607 	case DATA_SEGMENT_RELRO_END:
608 	  /* Operands swapped!  DATA_SEGMENT_RELRO_END(offset,exp)
609 	     has offset in expld.result and exp in lhs.  */
610 	  expld.dataseg.relro = exp_dataseg_relro_end;
611 	  expld.dataseg.relro_offset = expld.result.value;
612 	  if (expld.phase == lang_first_phase_enum
613 	      || expld.section != bfd_abs_section_ptr)
614 	    expld.result.valid_p = FALSE;
615 	  else if (expld.dataseg.phase == exp_dataseg_align_seen
616 		   || expld.dataseg.phase == exp_dataseg_adjust
617 		   || expld.dataseg.phase == exp_dataseg_relro_adjust
618 		   || expld.dataseg.phase == exp_dataseg_done)
619 	    {
620 	      if (expld.dataseg.phase == exp_dataseg_align_seen
621 		  || expld.dataseg.phase == exp_dataseg_relro_adjust)
622 		expld.dataseg.relro_end = lhs.value + expld.result.value;
623 
624 	      if (expld.dataseg.phase == exp_dataseg_relro_adjust
625 		  && (expld.dataseg.relro_end
626 		      & (expld.dataseg.pagesize - 1)))
627 		{
628 		  expld.dataseg.relro_end += expld.dataseg.pagesize - 1;
629 		  expld.dataseg.relro_end &= ~(expld.dataseg.pagesize - 1);
630 		  expld.result.value = (expld.dataseg.relro_end
631 					- expld.result.value);
632 		}
633 	      else
634 		expld.result.value = lhs.value;
635 
636 	      if (expld.dataseg.phase == exp_dataseg_align_seen)
637 		expld.dataseg.phase = exp_dataseg_relro_seen;
638 	    }
639 	  else
640 	    expld.result.valid_p = FALSE;
641 	  break;
642 
643 	default:
644 	  FAIL ();
645 	}
646     }
647 }
648 
649 static void
650 fold_trinary (etree_type *tree)
651 {
652   exp_fold_tree_1 (tree->trinary.cond);
653   if (expld.result.valid_p)
654     exp_fold_tree_1 (expld.result.value
655 		     ? tree->trinary.lhs
656 		     : tree->trinary.rhs);
657 }
658 
659 static void
660 fold_name (etree_type *tree)
661 {
662   memset (&expld.result, 0, sizeof (expld.result));
663 
664   switch (tree->type.node_code)
665     {
666     case SIZEOF_HEADERS:
667       if (expld.phase != lang_first_phase_enum)
668 	{
669 	  bfd_vma hdr_size = 0;
670 	  /* Don't find the real header size if only marking sections;
671 	     The bfd function may cache incorrect data.  */
672 	  if (expld.phase != lang_mark_phase_enum)
673 	    hdr_size = bfd_sizeof_headers (link_info.output_bfd, &link_info);
674 	  new_number (hdr_size);
675 	}
676       break;
677 
678     case DEFINED:
679       if (expld.phase != lang_first_phase_enum)
680 	{
681 	  struct bfd_link_hash_entry *h;
682 	  struct definedness_hash_entry *def;
683 
684 	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
685 					    &link_info,
686 					    tree->name.name,
687 					    FALSE, FALSE, TRUE);
688 	  new_number (h != NULL
689 		      && (h->type == bfd_link_hash_defined
690 			  || h->type == bfd_link_hash_defweak
691 			  || h->type == bfd_link_hash_common)
692 		      && ((def = symbol_defined (tree->name.name)) == NULL
693 			  || def->by_object
694 			  || def->iteration == (lang_statement_iteration & 1)));
695 	}
696       break;
697 
698     case NAME:
699       if (expld.assign_name != NULL
700 	  && strcmp (expld.assign_name, tree->name.name) == 0)
701 	{
702 	  /* Self-assignment is only allowed for absolute symbols
703 	     defined in a linker script.  */
704 	  struct bfd_link_hash_entry *h;
705 	  struct definedness_hash_entry *def;
706 
707 	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
708 					    &link_info,
709 					    tree->name.name,
710 					    FALSE, FALSE, TRUE);
711 	  if (!(h != NULL
712 		&& (h->type == bfd_link_hash_defined
713 		    || h->type == bfd_link_hash_defweak)
714 		&& h->u.def.section == bfd_abs_section_ptr
715 		&& (def = symbol_defined (tree->name.name)) != NULL
716 		&& def->iteration == (lang_statement_iteration & 1)))
717 	    expld.assign_name = NULL;
718 	}
719       if (expld.phase == lang_first_phase_enum)
720 	;
721       else if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
722 	new_rel_from_abs (expld.dot);
723       else
724 	{
725 	  struct bfd_link_hash_entry *h;
726 
727 	  h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
728 					    &link_info,
729 					    tree->name.name,
730 					    TRUE, FALSE, TRUE);
731 	  if (!h)
732 	    einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
733 	  else if (h->type == bfd_link_hash_defined
734 		   || h->type == bfd_link_hash_defweak)
735 	    {
736 	      asection *output_section;
737 
738 	      output_section = h->u.def.section->output_section;
739 	      if (output_section == NULL)
740 		{
741 		  if (expld.phase == lang_mark_phase_enum)
742 		    new_rel (h->u.def.value, h->u.def.section);
743 		  else
744 		    einfo (_("%X%S: unresolvable symbol `%s'"
745 			     " referenced in expression\n"),
746 			   tree, tree->name.name);
747 		}
748 	      else if (output_section == bfd_abs_section_ptr
749 		       && (expld.section != bfd_abs_section_ptr
750 			   || config.sane_expr))
751 		new_number (h->u.def.value + h->u.def.section->output_offset);
752 	      else
753 		new_rel (h->u.def.value + h->u.def.section->output_offset,
754 			 output_section);
755 	    }
756 	  else if (expld.phase == lang_final_phase_enum
757 		   || (expld.phase != lang_mark_phase_enum
758 		       && expld.assigning_to_dot))
759 	    einfo (_("%F%S: undefined symbol `%s'"
760 		     " referenced in expression\n"),
761 		   tree, tree->name.name);
762 	  else if (h->type == bfd_link_hash_new)
763 	    {
764 	      h->type = bfd_link_hash_undefined;
765 	      h->u.undef.abfd = NULL;
766 	      if (h->u.undef.next == NULL && h != link_info.hash->undefs_tail)
767 		bfd_link_add_undef (link_info.hash, h);
768 	    }
769 	}
770       break;
771 
772     case ADDR:
773       if (expld.phase != lang_first_phase_enum)
774 	{
775 	  lang_output_section_statement_type *os;
776 
777 	  os = lang_output_section_find (tree->name.name);
778 	  if (os == NULL)
779 	    {
780 	      if (expld.phase == lang_final_phase_enum)
781 		einfo (_("%F%S: undefined section `%s'"
782 			 " referenced in expression\n"),
783 		       tree, tree->name.name);
784 	    }
785 	  else if (os->processed_vma)
786 	    new_rel (0, os->bfd_section);
787 	}
788       break;
789 
790     case LOADADDR:
791       if (expld.phase != lang_first_phase_enum)
792 	{
793 	  lang_output_section_statement_type *os;
794 
795 	  os = lang_output_section_find (tree->name.name);
796 	  if (os == NULL)
797 	    {
798 	      if (expld.phase == lang_final_phase_enum)
799 		einfo (_("%F%S: undefined section `%s'"
800 			 " referenced in expression\n"),
801 		       tree, tree->name.name);
802 	    }
803 	  else if (os->processed_lma)
804 	    {
805 	      if (os->load_base == NULL)
806 		new_abs (os->bfd_section->lma);
807 	      else
808 		{
809 		  exp_fold_tree_1 (os->load_base);
810 		  if (expld.result.valid_p)
811 		    make_abs ();
812 		}
813 	    }
814 	}
815       break;
816 
817     case SIZEOF:
818     case ALIGNOF:
819       if (expld.phase != lang_first_phase_enum)
820 	{
821 	  lang_output_section_statement_type *os;
822 
823 	  os = lang_output_section_find (tree->name.name);
824 	  if (os == NULL)
825 	    {
826 	      if (expld.phase == lang_final_phase_enum)
827 		einfo (_("%F%S: undefined section `%s'"
828 			 " referenced in expression\n"),
829 		       tree, tree->name.name);
830 	      new_number (0);
831 	    }
832 	  else if (os->bfd_section != NULL)
833 	    {
834 	      bfd_vma val;
835 
836 	      if (tree->type.node_code == SIZEOF)
837 		val = (os->bfd_section->size
838 		       / bfd_octets_per_byte (link_info.output_bfd));
839 	      else
840 		val = (bfd_vma)1 << os->bfd_section->alignment_power;
841 
842 	      new_number (val);
843 	    }
844 	  else
845 	    new_number (0);
846 	}
847       break;
848 
849     case LENGTH:
850       {
851       if (expld.phase != lang_first_phase_enum)
852 	{
853 	  lang_memory_region_type *mem;
854 
855 	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
856 	  if (mem != NULL)
857 	    new_number (mem->length);
858 	  else
859 	    einfo (_("%F%S: undefined MEMORY region `%s'"
860 		     " referenced in expression\n"),
861 		   tree, tree->name.name);
862 	}
863       }
864       break;
865 
866     case ORIGIN:
867       if (expld.phase != lang_first_phase_enum)
868 	{
869 	  lang_memory_region_type *mem;
870 
871 	  mem = lang_memory_region_lookup (tree->name.name, FALSE);
872 	  if (mem != NULL)
873 	    new_rel_from_abs (mem->origin);
874 	  else
875 	    einfo (_("%F%S: undefined MEMORY region `%s'"
876 		     " referenced in expression\n"),
877 		   tree, tree->name.name);
878 	}
879       break;
880 
881     case CONSTANT:
882       if (strcmp (tree->name.name, "MAXPAGESIZE") == 0)
883 	new_number (config.maxpagesize);
884       else if (strcmp (tree->name.name, "COMMONPAGESIZE") == 0)
885 	new_number (config.commonpagesize);
886       else
887 	einfo (_("%F%S: unknown constant `%s' referenced in expression\n"),
888 	       tree, tree->name.name);
889       break;
890 
891     default:
892       FAIL ();
893       break;
894     }
895 }
896 
897 /* Return true if TREE is '.'.  */
898 
899 static bfd_boolean
900 is_dot (const etree_type *tree)
901 {
902   return (tree->type.node_class == etree_name
903 	  && tree->type.node_code == NAME
904 	  && tree->name.name[0] == '.'
905 	  && tree->name.name[1] == 0);
906 }
907 
908 /* Return true if TREE is a constant equal to VAL.  */
909 
910 static bfd_boolean
911 is_value (const etree_type *tree, bfd_vma val)
912 {
913   return (tree->type.node_class == etree_value
914 	  && tree->value.value == val);
915 }
916 
917 /* Return true if TREE is an absolute symbol equal to VAL defined in
918    a linker script.  */
919 
920 static bfd_boolean
921 is_sym_value (const etree_type *tree, bfd_vma val)
922 {
923   struct bfd_link_hash_entry *h;
924   struct definedness_hash_entry *def;
925 
926   return (tree->type.node_class == etree_name
927 	  && tree->type.node_code == NAME
928 	  && (def = symbol_defined (tree->name.name)) != NULL
929 	  && def->by_script
930 	  && def->iteration == (lang_statement_iteration & 1)
931 	  && (h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
932 						&link_info,
933 						tree->name.name,
934 						FALSE, FALSE, TRUE)) != NULL
935 	  && h->type == bfd_link_hash_defined
936 	  && h->u.def.section == bfd_abs_section_ptr
937 	  && h->u.def.value == val);
938 }
939 
940 /* Return true if TREE is ". != 0".  */
941 
942 static bfd_boolean
943 is_dot_ne_0 (const etree_type *tree)
944 {
945   return (tree->type.node_class == etree_binary
946 	  && tree->type.node_code == NE
947 	  && is_dot (tree->binary.lhs)
948 	  && is_value (tree->binary.rhs, 0));
949 }
950 
951 /* Return true if TREE is ". = . + 0" or ". = . + sym" where sym is an
952    absolute constant with value 0 defined in a linker script.  */
953 
954 static bfd_boolean
955 is_dot_plus_0 (const etree_type *tree)
956 {
957   return (tree->type.node_class == etree_binary
958 	  && tree->type.node_code == '+'
959 	  && is_dot (tree->binary.lhs)
960 	  && (is_value (tree->binary.rhs, 0)
961 	      || is_sym_value (tree->binary.rhs, 0)));
962 }
963 
964 /* Return true if TREE is "ALIGN (. != 0 ? some_expression : 1)".  */
965 
966 static bfd_boolean
967 is_align_conditional (const etree_type *tree)
968 {
969   if (tree->type.node_class == etree_unary
970       && tree->type.node_code == ALIGN_K)
971     {
972       tree = tree->unary.child;
973       return (tree->type.node_class == etree_trinary
974 	      && is_dot_ne_0 (tree->trinary.cond)
975 	      && is_value (tree->trinary.rhs, 1));
976     }
977   return FALSE;
978 }
979 
980 /* Subroutine of exp_fold_tree_1 for copying a symbol type.  */
981 
982 static void
983 try_copy_symbol_type (struct bfd_link_hash_entry *h, etree_type *src)
984 {
985   if (src->type.node_class == etree_name)
986     {
987       struct bfd_link_hash_entry *hsrc;
988 
989       hsrc = bfd_link_hash_lookup (link_info.hash, src->name.name,
990 				    FALSE, FALSE, TRUE);
991       if (hsrc)
992 	bfd_copy_link_hash_symbol_type (link_info.output_bfd, h,
993 						    hsrc);
994     }
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.result.valid_p
1073 		       && expld.result.value == 0
1074 		       && (is_value (tree->assign.src, 0)
1075 			   || is_sym_value (tree->assign.src, 0)
1076 			   || is_dot_plus_0 (tree->assign.src)
1077 			   || is_align_conditional (tree->assign.src))))
1078 		expld.section->flags |= SEC_KEEP;
1079 
1080 	      if (!expld.result.valid_p)
1081 		{
1082 		  if (expld.phase != lang_mark_phase_enum)
1083 		    einfo (_("%F%S invalid assignment to"
1084 			     " location counter\n"), tree);
1085 		}
1086 	      else if (expld.dotp == NULL)
1087 		einfo (_("%F%S assignment to location counter"
1088 			 " invalid outside of SECTIONS\n"), tree);
1089 
1090 	      /* After allocation, assignment to dot should not be
1091 		 done inside an output section since allocation adds a
1092 		 padding statement that effectively duplicates the
1093 		 assignment.  */
1094 	      else if (expld.phase <= lang_allocating_phase_enum
1095 		       || expld.section == bfd_abs_section_ptr)
1096 		{
1097 		  bfd_vma nextdot;
1098 
1099 		  nextdot = expld.result.value;
1100 		  if (expld.result.section != NULL)
1101 		    nextdot += expld.result.section->vma;
1102 		  else
1103 		    nextdot += expld.section->vma;
1104 		  if (nextdot < expld.dot
1105 		      && expld.section != bfd_abs_section_ptr)
1106 		    einfo (_("%F%S cannot move location counter backwards"
1107 			     " (from %V to %V)\n"),
1108 			   tree, expld.dot, nextdot);
1109 		  else
1110 		    {
1111 		      expld.dot = nextdot;
1112 		      *expld.dotp = nextdot;
1113 		    }
1114 		}
1115 	    }
1116 	  else
1117 	    memset (&expld.result, 0, sizeof (expld.result));
1118 	}
1119       else
1120 	{
1121 	  struct bfd_link_hash_entry *h = NULL;
1122 
1123 	  if (tree->type.node_class == etree_provide)
1124 	    {
1125 	      h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
1126 					FALSE, FALSE, TRUE);
1127 	      if (h == NULL
1128 		  || !(h->type == bfd_link_hash_new
1129 		       || h->type == bfd_link_hash_undefined
1130 		       || h->type == bfd_link_hash_undefweak
1131 		       || h->linker_def))
1132 		{
1133 		  /* Do nothing.  The symbol was never referenced, or
1134 		     was defined in some object file.  Note that
1135 		     undefweak symbols are defined by PROVIDE.  This
1136 		     is to support glibc use of __rela_iplt_start and
1137 		     similar weak references.  */
1138 		  break;
1139 		}
1140 	    }
1141 
1142 	  expld.assign_name = tree->assign.dst;
1143 	  exp_fold_tree_1 (tree->assign.src);
1144 	  /* expld.assign_name remaining equal to tree->assign.dst
1145 	     below indicates the evaluation of tree->assign.src did
1146 	     not use the value of tree->assign.dst.  We don't allow
1147 	     self assignment until the final phase for two reasons:
1148 	     1) Expressions are evaluated multiple times.  With
1149 	     relaxation, the number of times may vary.
1150 	     2) Section relative symbol values cannot be correctly
1151 	     converted to absolute values, as is required by many
1152 	     expressions, until final section sizing is complete.  */
1153 	  if ((expld.result.valid_p
1154 	       && (expld.phase == lang_final_phase_enum
1155 		   || expld.assign_name != NULL))
1156 	      || (expld.phase <= lang_mark_phase_enum
1157 		  && tree->type.node_class == etree_assign
1158 		  && tree->assign.defsym))
1159 	    {
1160 	      if (h == NULL)
1161 		{
1162 		  h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
1163 					    TRUE, FALSE, TRUE);
1164 		  if (h == NULL)
1165 		    einfo (_("%P%F:%s: hash creation failed\n"),
1166 			   tree->assign.dst);
1167 		}
1168 
1169 	      if (expld.result.section == NULL)
1170 		expld.result.section = expld.section;
1171 	      if (!update_definedness (tree->assign.dst, h) && 0)
1172 		{
1173 		  /* Symbol was already defined.  For now this error
1174 		     is disabled because it causes failures in the ld
1175 		     testsuite: ld-elf/var1, ld-scripts/defined5, and
1176 		     ld-scripts/pr14962.  Some of these no doubt
1177 		     reflect scripts used in the wild.  */
1178 		  (*link_info.callbacks->multiple_definition)
1179 		    (&link_info, h, link_info.output_bfd,
1180 		     expld.result.section, expld.result.value);
1181 		}
1182 	      h->type = bfd_link_hash_defined;
1183 	      h->u.def.value = expld.result.value;
1184 	      h->u.def.section = expld.result.section;
1185 	      h->linker_def = 0;
1186 	      if (tree->type.node_class == etree_provide)
1187 		tree->type.node_class = etree_provided;
1188 
1189 	      /* Copy the symbol type if this is a simple assignment of
1190 		 one symbol to another.  Also, handle the case of a foldable
1191 		 ternary conditional with names on either side.  */
1192 	      if (tree->assign.src->type.node_class == etree_name)
1193 		try_copy_symbol_type (h, tree->assign.src);
1194 	      else if (tree->assign.src->type.node_class == etree_trinary)
1195 		{
1196 		  exp_fold_tree_1 (tree->assign.src->trinary.cond);
1197 		  if (expld.result.valid_p)
1198 		    {
1199 		      if (expld.result.value
1200 			  && tree->assign.src->trinary.lhs->type.node_class
1201 			     == etree_name)
1202 			try_copy_symbol_type (h, tree->assign.src->trinary.lhs);
1203 
1204 		      if (!expld.result.value
1205 			  && tree->assign.src->trinary.rhs->type.node_class
1206 			     == etree_name)
1207 			try_copy_symbol_type (h, tree->assign.src->trinary.rhs);
1208 		    }
1209 		}
1210 	    }
1211 	  else if (expld.phase == lang_final_phase_enum)
1212 	    {
1213 	      h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
1214 					FALSE, FALSE, TRUE);
1215 	      if (h != NULL
1216 		  && h->type == bfd_link_hash_new)
1217 		h->type = bfd_link_hash_undefined;
1218 	    }
1219 	  expld.assign_name = NULL;
1220 	}
1221       break;
1222 
1223     case etree_name:
1224       fold_name (tree);
1225       break;
1226 
1227     default:
1228       FAIL ();
1229       memset (&expld.result, 0, sizeof (expld.result));
1230       break;
1231     }
1232 }
1233 
1234 void
1235 exp_fold_tree (etree_type *tree, asection *current_section, bfd_vma *dotp)
1236 {
1237   expld.rel_from_abs = FALSE;
1238   expld.dot = *dotp;
1239   expld.dotp = dotp;
1240   expld.section = current_section;
1241   exp_fold_tree_1 (tree);
1242 }
1243 
1244 void
1245 exp_fold_tree_no_dot (etree_type *tree)
1246 {
1247   expld.rel_from_abs = FALSE;
1248   expld.dot = 0;
1249   expld.dotp = NULL;
1250   expld.section = bfd_abs_section_ptr;
1251   exp_fold_tree_1 (tree);
1252 }
1253 
1254 etree_type *
1255 exp_binop (int code, etree_type *lhs, etree_type *rhs)
1256 {
1257   etree_type value, *new_e;
1258 
1259   value.type.node_code = code;
1260   value.type.filename = lhs->type.filename;
1261   value.type.lineno = lhs->type.lineno;
1262   value.binary.lhs = lhs;
1263   value.binary.rhs = rhs;
1264   value.type.node_class = etree_binary;
1265   exp_fold_tree_no_dot (&value);
1266   if (expld.result.valid_p)
1267     return exp_intop (expld.result.value);
1268 
1269   new_e = (etree_type *) stat_alloc (sizeof (new_e->binary));
1270   memcpy (new_e, &value, sizeof (new_e->binary));
1271   return new_e;
1272 }
1273 
1274 etree_type *
1275 exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
1276 {
1277   etree_type value, *new_e;
1278 
1279   value.type.node_code = code;
1280   value.type.filename = cond->type.filename;
1281   value.type.lineno = cond->type.lineno;
1282   value.trinary.lhs = lhs;
1283   value.trinary.cond = cond;
1284   value.trinary.rhs = rhs;
1285   value.type.node_class = etree_trinary;
1286   exp_fold_tree_no_dot (&value);
1287   if (expld.result.valid_p)
1288     return exp_intop (expld.result.value);
1289 
1290   new_e = (etree_type *) stat_alloc (sizeof (new_e->trinary));
1291   memcpy (new_e, &value, sizeof (new_e->trinary));
1292   return new_e;
1293 }
1294 
1295 etree_type *
1296 exp_unop (int code, etree_type *child)
1297 {
1298   etree_type value, *new_e;
1299 
1300   value.unary.type.node_code = code;
1301   value.unary.type.filename = child->type.filename;
1302   value.unary.type.lineno = child->type.lineno;
1303   value.unary.child = child;
1304   value.unary.type.node_class = etree_unary;
1305   exp_fold_tree_no_dot (&value);
1306   if (expld.result.valid_p)
1307     return exp_intop (expld.result.value);
1308 
1309   new_e = (etree_type *) stat_alloc (sizeof (new_e->unary));
1310   memcpy (new_e, &value, sizeof (new_e->unary));
1311   return new_e;
1312 }
1313 
1314 etree_type *
1315 exp_nameop (int code, const char *name)
1316 {
1317   etree_type value, *new_e;
1318 
1319   value.name.type.node_code = code;
1320   value.name.type.filename = ldlex_filename ();
1321   value.name.type.lineno = lineno;
1322   value.name.name = name;
1323   value.name.type.node_class = etree_name;
1324 
1325   exp_fold_tree_no_dot (&value);
1326   if (expld.result.valid_p)
1327     return exp_intop (expld.result.value);
1328 
1329   new_e = (etree_type *) stat_alloc (sizeof (new_e->name));
1330   memcpy (new_e, &value, sizeof (new_e->name));
1331   return new_e;
1332 
1333 }
1334 
1335 static etree_type *
1336 exp_assop (const char *dst,
1337 	   etree_type *src,
1338 	   enum node_tree_enum class,
1339 	   bfd_boolean defsym,
1340 	   bfd_boolean hidden)
1341 {
1342   etree_type *n;
1343 
1344   n = (etree_type *) stat_alloc (sizeof (n->assign));
1345   n->assign.type.node_code = '=';
1346   n->assign.type.filename = src->type.filename;
1347   n->assign.type.lineno = src->type.lineno;
1348   n->assign.type.node_class = class;
1349   n->assign.src = src;
1350   n->assign.dst = dst;
1351   n->assign.defsym = defsym;
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, FALSE, 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, TRUE, 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, FALSE, 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