* hppabsd-core.c (hppabsd_core_core_file_p): Sanity check the
[deliverable/binutils-gdb.git] / bfd / reloc.c
1 /* BFD support for handling relocation entries.
2 Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
3 Written by Cygnus Support.
4
5 This file is part of BFD, the Binary File Descriptor library.
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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
20
21 /*
22 SECTION
23 Relocations
24
25 BFD maintains relocations in much the same way it maintains
26 symbols: they are left alone until required, then read in
27 en-mass and translated into an internal form. A common
28 routine <<bfd_perform_relocation>> acts upon the
29 canonical form to do the fixup.
30
31 Relocations are maintained on a per section basis,
32 while symbols are maintained on a per BFD basis.
33
34 All that a back end has to do to fit the BFD interface is to create
35 a <<struct reloc_cache_entry>> for each relocation
36 in a particular section, and fill in the right bits of the structures.
37
38 @menu
39 @* typedef arelent::
40 @* howto manager::
41 @end menu
42
43 */
44 #include "bfd.h"
45 #include "sysdep.h"
46 #include "bfdlink.h"
47 #include "libbfd.h"
48 /*
49 DOCDD
50 INODE
51 typedef arelent, howto manager, Relocations, Relocations
52
53 SUBSECTION
54 typedef arelent
55
56 This is the structure of a relocation entry:
57
58 CODE_FRAGMENT
59 .
60 .typedef enum bfd_reloc_status
61 .{
62 . {* No errors detected *}
63 . bfd_reloc_ok,
64 .
65 . {* The relocation was performed, but there was an overflow. *}
66 . bfd_reloc_overflow,
67 .
68 . {* The address to relocate was not within the section supplied. *}
69 . bfd_reloc_outofrange,
70 .
71 . {* Used by special functions *}
72 . bfd_reloc_continue,
73 .
74 . {* Unsupported relocation size requested. *}
75 . bfd_reloc_notsupported,
76 .
77 . {* Unused *}
78 . bfd_reloc_other,
79 .
80 . {* The symbol to relocate against was undefined. *}
81 . bfd_reloc_undefined,
82 .
83 . {* The relocation was performed, but may not be ok - presently
84 . generated only when linking i960 coff files with i960 b.out
85 . symbols. If this type is returned, the error_message argument
86 . to bfd_perform_relocation will be set. *}
87 . bfd_reloc_dangerous
88 . }
89 . bfd_reloc_status_type;
90 .
91 .
92 .typedef struct reloc_cache_entry
93 .{
94 . {* A pointer into the canonical table of pointers *}
95 . struct symbol_cache_entry **sym_ptr_ptr;
96 .
97 . {* offset in section *}
98 . bfd_size_type address;
99 .
100 . {* addend for relocation value *}
101 . bfd_vma addend;
102 .
103 . {* Pointer to how to perform the required relocation *}
104 . const struct reloc_howto_struct *howto;
105 .
106 .} arelent;
107
108 */
109
110 /*
111 DESCRIPTION
112
113 Here is a description of each of the fields within an <<arelent>>:
114
115 o <<sym_ptr_ptr>>
116
117 The symbol table pointer points to a pointer to the symbol
118 associated with the relocation request. It is
119 the pointer into the table returned by the back end's
120 <<get_symtab>> action. @xref{Symbols}. The symbol is referenced
121 through a pointer to a pointer so that tools like the linker
122 can fix up all the symbols of the same name by modifying only
123 one pointer. The relocation routine looks in the symbol and
124 uses the base of the section the symbol is attached to and the
125 value of the symbol as the initial relocation offset. If the
126 symbol pointer is zero, then the section provided is looked up.
127
128 o <<address>>
129
130 The <<address>> field gives the offset in bytes from the base of
131 the section data which owns the relocation record to the first
132 byte of relocatable information. The actual data relocated
133 will be relative to this point; for example, a relocation
134 type which modifies the bottom two bytes of a four byte word
135 would not touch the first byte pointed to in a big endian
136 world.
137
138 o <<addend>>
139
140 The <<addend>> is a value provided by the back end to be added (!)
141 to the relocation offset. Its interpretation is dependent upon
142 the howto. For example, on the 68k the code:
143
144
145 | char foo[];
146 | main()
147 | {
148 | return foo[0x12345678];
149 | }
150
151 Could be compiled into:
152
153 | linkw fp,#-4
154 | moveb @@#12345678,d0
155 | extbl d0
156 | unlk fp
157 | rts
158
159
160 This could create a reloc pointing to <<foo>>, but leave the
161 offset in the data, something like:
162
163
164 |RELOCATION RECORDS FOR [.text]:
165 |offset type value
166 |00000006 32 _foo
167 |
168 |00000000 4e56 fffc ; linkw fp,#-4
169 |00000004 1039 1234 5678 ; moveb @@#12345678,d0
170 |0000000a 49c0 ; extbl d0
171 |0000000c 4e5e ; unlk fp
172 |0000000e 4e75 ; rts
173
174
175 Using coff and an 88k, some instructions don't have enough
176 space in them to represent the full address range, and
177 pointers have to be loaded in two parts. So you'd get something like:
178
179
180 | or.u r13,r0,hi16(_foo+0x12345678)
181 | ld.b r2,r13,lo16(_foo+0x12345678)
182 | jmp r1
183
184
185 This should create two relocs, both pointing to <<_foo>>, and with
186 0x12340000 in their addend field. The data would consist of:
187
188
189 |RELOCATION RECORDS FOR [.text]:
190 |offset type value
191 |00000002 HVRT16 _foo+0x12340000
192 |00000006 LVRT16 _foo+0x12340000
193 |
194 |00000000 5da05678 ; or.u r13,r0,0x5678
195 |00000004 1c4d5678 ; ld.b r2,r13,0x5678
196 |00000008 f400c001 ; jmp r1
197
198
199 The relocation routine digs out the value from the data, adds
200 it to the addend to get the original offset, and then adds the
201 value of <<_foo>>. Note that all 32 bits have to be kept around
202 somewhere, to cope with carry from bit 15 to bit 16.
203
204 One further example is the sparc and the a.out format. The
205 sparc has a similar problem to the 88k, in that some
206 instructions don't have room for an entire offset, but on the
207 sparc the parts are created in odd sized lumps. The designers of
208 the a.out format chose to not use the data within the section
209 for storing part of the offset; all the offset is kept within
210 the reloc. Anything in the data should be ignored.
211
212 | save %sp,-112,%sp
213 | sethi %hi(_foo+0x12345678),%g2
214 | ldsb [%g2+%lo(_foo+0x12345678)],%i0
215 | ret
216 | restore
217
218 Both relocs contain a pointer to <<foo>>, and the offsets
219 contain junk.
220
221
222 |RELOCATION RECORDS FOR [.text]:
223 |offset type value
224 |00000004 HI22 _foo+0x12345678
225 |00000008 LO10 _foo+0x12345678
226 |
227 |00000000 9de3bf90 ; save %sp,-112,%sp
228 |00000004 05000000 ; sethi %hi(_foo+0),%g2
229 |00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0
230 |0000000c 81c7e008 ; ret
231 |00000010 81e80000 ; restore
232
233
234 o <<howto>>
235
236 The <<howto>> field can be imagined as a
237 relocation instruction. It is a pointer to a structure which
238 contains information on what to do with all of the other
239 information in the reloc record and data section. A back end
240 would normally have a relocation instruction set and turn
241 relocations into pointers to the correct structure on input -
242 but it would be possible to create each howto field on demand.
243
244 */
245
246 /*
247 SUBSUBSECTION
248 <<enum complain_overflow>>
249
250 Indicates what sort of overflow checking should be done when
251 performing a relocation.
252
253 CODE_FRAGMENT
254 .
255 .enum complain_overflow
256 .{
257 . {* Do not complain on overflow. *}
258 . complain_overflow_dont,
259 .
260 . {* Complain if the bitfield overflows, whether it is considered
261 . as signed or unsigned. *}
262 . complain_overflow_bitfield,
263 .
264 . {* Complain if the value overflows when considered as signed
265 . number. *}
266 . complain_overflow_signed,
267 .
268 . {* Complain if the value overflows when considered as an
269 . unsigned number. *}
270 . complain_overflow_unsigned
271 .};
272
273 */
274
275 /*
276 SUBSUBSECTION
277 <<reloc_howto_type>>
278
279 The <<reloc_howto_type>> is a structure which contains all the
280 information that libbfd needs to know to tie up a back end's data.
281
282 CODE_FRAGMENT
283 .struct symbol_cache_entry; {* Forward declaration *}
284 .
285 .typedef struct reloc_howto_struct
286 .{
287 . {* The type field has mainly a documetary use - the back end can
288 . do what it wants with it, though normally the back end's
289 . external idea of what a reloc number is stored
290 . in this field. For example, a PC relative word relocation
291 . in a coff environment has the type 023 - because that's
292 . what the outside world calls a R_PCRWORD reloc. *}
293 . unsigned int type;
294 .
295 . {* The value the final relocation is shifted right by. This drops
296 . unwanted data from the relocation. *}
297 . unsigned int rightshift;
298 .
299 . {* The size of the item to be relocated. This is *not* a
300 . power-of-two measure. To get the number of bytes operated
301 . on by a type of relocation, use bfd_get_reloc_size. *}
302 . int size;
303 .
304 . {* The number of bits in the item to be relocated. This is used
305 . when doing overflow checking. *}
306 . unsigned int bitsize;
307 .
308 . {* Notes that the relocation is relative to the location in the
309 . data section of the addend. The relocation function will
310 . subtract from the relocation value the address of the location
311 . being relocated. *}
312 . boolean pc_relative;
313 .
314 . {* The bit position of the reloc value in the destination.
315 . The relocated value is left shifted by this amount. *}
316 . unsigned int bitpos;
317 .
318 . {* What type of overflow error should be checked for when
319 . relocating. *}
320 . enum complain_overflow complain_on_overflow;
321 .
322 . {* If this field is non null, then the supplied function is
323 . called rather than the normal function. This allows really
324 . strange relocation methods to be accomodated (e.g., i960 callj
325 . instructions). *}
326 . bfd_reloc_status_type (*special_function)
327 . PARAMS ((bfd *abfd,
328 . arelent *reloc_entry,
329 . struct symbol_cache_entry *symbol,
330 . PTR data,
331 . asection *input_section,
332 . bfd *output_bfd,
333 . char **error_message));
334 .
335 . {* The textual name of the relocation type. *}
336 . char *name;
337 .
338 . {* When performing a partial link, some formats must modify the
339 . relocations rather than the data - this flag signals this.*}
340 . boolean partial_inplace;
341 .
342 . {* The src_mask selects which parts of the read in data
343 . are to be used in the relocation sum. E.g., if this was an 8 bit
344 . bit of data which we read and relocated, this would be
345 . 0x000000ff. When we have relocs which have an addend, such as
346 . sun4 extended relocs, the value in the offset part of a
347 . relocating field is garbage so we never use it. In this case
348 . the mask would be 0x00000000. *}
349 . bfd_vma src_mask;
350 .
351 . {* The dst_mask selects which parts of the instruction are replaced
352 . into the instruction. In most cases src_mask == dst_mask,
353 . except in the above special case, where dst_mask would be
354 . 0x000000ff, and src_mask would be 0x00000000. *}
355 . bfd_vma dst_mask;
356 .
357 . {* When some formats create PC relative instructions, they leave
358 . the value of the pc of the place being relocated in the offset
359 . slot of the instruction, so that a PC relative relocation can
360 . be made just by adding in an ordinary offset (e.g., sun3 a.out).
361 . Some formats leave the displacement part of an instruction
362 . empty (e.g., m88k bcs); this flag signals the fact.*}
363 . boolean pcrel_offset;
364 .
365 .} reloc_howto_type;
366
367 */
368
369 /*
370 FUNCTION
371 The HOWTO Macro
372
373 DESCRIPTION
374 The HOWTO define is horrible and will go away.
375
376
377 .#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
378 . {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
379
380 DESCRIPTION
381 And will be replaced with the totally magic way. But for the
382 moment, we are compatible, so do it this way.
383
384
385 .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
386 .
387 DESCRIPTION
388 Helper routine to turn a symbol into a relocation value.
389
390 .#define HOWTO_PREPARE(relocation, symbol) \
391 . { \
392 . if (symbol != (asymbol *)NULL) { \
393 . if (bfd_is_com_section (symbol->section)) { \
394 . relocation = 0; \
395 . } \
396 . else { \
397 . relocation = symbol->value; \
398 . } \
399 . } \
400 .}
401
402 */
403
404 /*
405 FUNCTION
406 bfd_get_reloc_size
407
408 SYNOPSIS
409 int bfd_get_reloc_size (const reloc_howto_type *);
410
411 DESCRIPTION
412 For a reloc_howto_type that operates on a fixed number of bytes,
413 this returns the number of bytes operated on.
414 */
415
416 int
417 bfd_get_reloc_size (howto)
418 const reloc_howto_type *howto;
419 {
420 switch (howto->size)
421 {
422 case 0: return 1;
423 case 1: return 2;
424 case 2: return 4;
425 case 3: return 0;
426 case 4: return 8;
427 case -2: return 4;
428 default: abort ();
429 }
430 }
431
432 /*
433 TYPEDEF
434 arelent_chain
435
436 DESCRIPTION
437
438 How relocs are tied together in an <<asection>>:
439
440 .typedef unsigned char bfd_byte;
441 .
442 .typedef struct relent_chain {
443 . arelent relent;
444 . struct relent_chain *next;
445 .} arelent_chain;
446
447 */
448
449
450
451 /*
452 FUNCTION
453 bfd_perform_relocation
454
455 SYNOPSIS
456 bfd_reloc_status_type
457 bfd_perform_relocation
458 (bfd *abfd,
459 arelent *reloc_entry,
460 PTR data,
461 asection *input_section,
462 bfd *output_bfd,
463 char **error_message);
464
465 DESCRIPTION
466 If @var{output_bfd} is supplied to this function, the
467 generated image will be relocatable; the relocations are
468 copied to the output file after they have been changed to
469 reflect the new state of the world. There are two ways of
470 reflecting the results of partial linkage in an output file:
471 by modifying the output data in place, and by modifying the
472 relocation record. Some native formats (e.g., basic a.out and
473 basic coff) have no way of specifying an addend in the
474 relocation type, so the addend has to go in the output data.
475 This is no big deal since in these formats the output data
476 slot will always be big enough for the addend. Complex reloc
477 types with addends were invented to solve just this problem.
478 The @var{error_message} argument is set to an error message if
479 this return @code{bfd_reloc_dangerous}.
480
481 */
482
483
484 bfd_reloc_status_type
485 bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd,
486 error_message)
487 bfd *abfd;
488 arelent *reloc_entry;
489 PTR data;
490 asection *input_section;
491 bfd *output_bfd;
492 char **error_message;
493 {
494 bfd_vma relocation;
495 bfd_reloc_status_type flag = bfd_reloc_ok;
496 bfd_size_type addr = reloc_entry->address;
497 bfd_vma output_base = 0;
498 const reloc_howto_type *howto = reloc_entry->howto;
499 asection *reloc_target_output_section;
500 asymbol *symbol;
501
502 symbol = *(reloc_entry->sym_ptr_ptr);
503 if ((symbol->section == &bfd_abs_section)
504 && output_bfd != (bfd *) NULL)
505 {
506 reloc_entry->address += input_section->output_offset;
507 return bfd_reloc_ok;
508 }
509
510 /* If we are not producing relocateable output, return an error if
511 the symbol is not defined. An undefined weak symbol is
512 considered to have a value of zero (SVR4 ABI, p. 4-27). */
513 if (symbol->section == &bfd_und_section
514 && (symbol->flags & BSF_WEAK) == 0
515 && output_bfd == (bfd *) NULL)
516 flag = bfd_reloc_undefined;
517
518 /* If there is a function supplied to handle this relocation type,
519 call it. It'll return `bfd_reloc_continue' if further processing
520 can be done. */
521 if (howto->special_function)
522 {
523 bfd_reloc_status_type cont;
524 cont = howto->special_function (abfd, reloc_entry, symbol, data,
525 input_section, output_bfd,
526 error_message);
527 if (cont != bfd_reloc_continue)
528 return cont;
529 }
530
531 /* Is the address of the relocation really within the section? */
532 if (reloc_entry->address > input_section->_cooked_size)
533 return bfd_reloc_outofrange;
534
535 /* Work out which section the relocation is targetted at and the
536 initial relocation command value. */
537
538 /* Get symbol value. (Common symbols are special.) */
539 if (bfd_is_com_section (symbol->section))
540 relocation = 0;
541 else
542 relocation = symbol->value;
543
544
545 reloc_target_output_section = symbol->section->output_section;
546
547 /* Convert input-section-relative symbol value to absolute. */
548 if (output_bfd && howto->partial_inplace == false)
549 output_base = 0;
550 else
551 output_base = reloc_target_output_section->vma;
552
553 relocation += output_base + symbol->section->output_offset;
554
555 /* Add in supplied addend. */
556 relocation += reloc_entry->addend;
557
558 /* Here the variable relocation holds the final address of the
559 symbol we are relocating against, plus any addend. */
560
561 if (howto->pc_relative == true)
562 {
563 /* This is a PC relative relocation. We want to set RELOCATION
564 to the distance between the address of the symbol and the
565 location. RELOCATION is already the address of the symbol.
566
567 We start by subtracting the address of the section containing
568 the location.
569
570 If pcrel_offset is set, we must further subtract the position
571 of the location within the section. Some targets arrange for
572 the addend to be the negative of the position of the location
573 within the section; for example, i386-aout does this. For
574 i386-aout, pcrel_offset is false. Some other targets do not
575 include the position of the location; for example, m88kbcs,
576 or ELF. For those targets, pcrel_offset is true.
577
578 If we are producing relocateable output, then we must ensure
579 that this reloc will be correctly computed when the final
580 relocation is done. If pcrel_offset is false we want to wind
581 up with the negative of the location within the section,
582 which means we must adjust the existing addend by the change
583 in the location within the section. If pcrel_offset is true
584 we do not want to adjust the existing addend at all.
585
586 FIXME: This seems logical to me, but for the case of
587 producing relocateable output it is not what the code
588 actually does. I don't want to change it, because it seems
589 far too likely that something will break. */
590
591 relocation -=
592 input_section->output_section->vma + input_section->output_offset;
593
594 if (howto->pcrel_offset == true)
595 relocation -= reloc_entry->address;
596 }
597
598 if (output_bfd != (bfd *) NULL)
599 {
600 if (howto->partial_inplace == false)
601 {
602 /* This is a partial relocation, and we want to apply the relocation
603 to the reloc entry rather than the raw data. Modify the reloc
604 inplace to reflect what we now know. */
605 reloc_entry->addend = relocation;
606 reloc_entry->address += input_section->output_offset;
607 return flag;
608 }
609 else
610 {
611 /* This is a partial relocation, but inplace, so modify the
612 reloc record a bit.
613
614 If we've relocated with a symbol with a section, change
615 into a ref to the section belonging to the symbol. */
616
617 reloc_entry->address += input_section->output_offset;
618
619 /* WTF?? */
620 if (abfd->xvec->flavour == bfd_target_coff_flavour
621 && strcmp (abfd->xvec->name, "aixcoff-rs6000") != 0)
622 {
623 #if 1
624 /* For m68k-coff, the addend was being subtracted twice during
625 relocation with -r. Removing the line below this comment
626 fixes that problem; see PR 2953.
627
628 However, Ian wrote the following, regarding removing the line below,
629 which explains why it is still enabled: --djm
630
631 If you put a patch like that into BFD you need to check all the COFF
632 linkers. I am fairly certain that patch will break coff-i386 (e.g.,
633 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
634 problem in a different way. There may very well be a reason that the
635 code works as it does.
636
637 Hmmm. The first obvious point is that bfd_perform_relocation should
638 not have any tests that depend upon the flavour. It's seem like
639 entirely the wrong place for such a thing. The second obvious point
640 is that the current code ignores the reloc addend when producing
641 relocateable output for COFF. That's peculiar. In fact, I really
642 have no idea what the point of the line you want to remove is.
643
644 A typical COFF reloc subtracts the old value of the symbol and adds in
645 the new value to the location in the object file (if it's a pc
646 relative reloc it adds the difference between the symbol value and the
647 location). When relocating we need to preserve that property.
648
649 BFD handles this by setting the addend to the negative of the old
650 value of the symbol. Unfortunately it handles common symbols in a
651 non-standard way (it doesn't subtract the old value) but that's a
652 different story (we can't change it without losing backward
653 compatibility with old object files) (coff-i386 does subtract the old
654 value, to be compatible with existing coff-i386 targets, like SCO).
655
656 So everything works fine when not producing relocateable output. When
657 we are producing relocateable output, logically we should do exactly
658 what we do when not producing relocateable output. Therefore, your
659 patch is correct. In fact, it should probably always just set
660 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
661 add the value into the object file. This won't hurt the COFF code,
662 which doesn't use the addend; I'm not sure what it will do to other
663 formats (the thing to check for would be whether any formats both use
664 the addend and set partial_inplace).
665
666 When I wanted to make coff-i386 produce relocateable output, I ran
667 into the problem that you are running into: I wanted to remove that
668 line. Rather than risk it, I made the coff-i386 relocs use a special
669 function; it's coff_i386_reloc in coff-i386.c. The function
670 specifically adds the addend field into the object file, knowing that
671 bfd_perform_relocation is not going to. If you remove that line, then
672 coff-i386.c will wind up adding the addend field in twice. It's
673 trivial to fix; it just needs to be done.
674
675 The problem with removing the line is just that it may break some
676 working code. With BFD it's hard to be sure of anything. The right
677 way to deal with this is simply to build and test at least all the
678 supported COFF targets. It should be straightforward if time and disk
679 space consuming. For each target:
680 1) build the linker
681 2) generate some executable, and link it using -r (I would
682 probably use paranoia.o and link against newlib/libc.a, which
683 for all the supported targets would be available in
684 /usr/cygnus/progressive/H-host/target/lib/libc.a).
685 3) make the change to reloc.c
686 4) rebuild the linker
687 5) repeat step 2
688 6) if the resulting object files are the same, you have at least
689 made it no worse
690 7) if they are different you have to figure out which version is
691 right
692 */
693 relocation -= reloc_entry->addend;
694 #endif
695 reloc_entry->addend = 0;
696 }
697 else
698 {
699 reloc_entry->addend = relocation;
700 }
701 }
702 }
703 else
704 {
705 reloc_entry->addend = 0;
706 }
707
708 /* FIXME: This overflow checking is incomplete, because the value
709 might have overflowed before we get here. For a correct check we
710 need to compute the value in a size larger than bitsize, but we
711 can't reasonably do that for a reloc the same size as a host
712 machine word.
713 FIXME: We should also do overflow checking on the result after
714 adding in the value contained in the object file. */
715 if (howto->complain_on_overflow != complain_overflow_dont)
716 {
717 bfd_vma check;
718
719 /* Get the value that will be used for the relocation, but
720 starting at bit position zero. */
721 if (howto->rightshift > howto->bitpos)
722 check = relocation >> (howto->rightshift - howto->bitpos);
723 else
724 check = relocation << (howto->bitpos - howto->rightshift);
725 switch (howto->complain_on_overflow)
726 {
727 case complain_overflow_signed:
728 {
729 /* Assumes two's complement. */
730 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
731 bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
732
733 /* The above right shift is incorrect for a signed value.
734 Fix it up by forcing on the upper bits. */
735 if (howto->rightshift > howto->bitpos
736 && (bfd_signed_vma) relocation < 0)
737 check |= ((bfd_vma) - 1
738 & ~((bfd_vma) - 1
739 >> (howto->rightshift - howto->bitpos)));
740 if ((bfd_signed_vma) check > reloc_signed_max
741 || (bfd_signed_vma) check < reloc_signed_min)
742 flag = bfd_reloc_overflow;
743 }
744 break;
745 case complain_overflow_unsigned:
746 {
747 /* Assumes two's complement. This expression avoids
748 overflow if howto->bitsize is the number of bits in
749 bfd_vma. */
750 bfd_vma reloc_unsigned_max =
751 (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
752
753 if ((bfd_vma) check > reloc_unsigned_max)
754 flag = bfd_reloc_overflow;
755 }
756 break;
757 case complain_overflow_bitfield:
758 {
759 /* Assumes two's complement. This expression avoids
760 overflow if howto->bitsize is the number of bits in
761 bfd_vma. */
762 bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
763
764 if (((bfd_vma) check & ~reloc_bits) != 0
765 && ((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
766 {
767 /* The above right shift is incorrect for a signed
768 value. See if turning on the upper bits fixes the
769 overflow. */
770 if (howto->rightshift > howto->bitpos
771 && (bfd_signed_vma) relocation < 0)
772 {
773 check |= ((bfd_vma) - 1
774 & ~((bfd_vma) - 1
775 >> (howto->rightshift - howto->bitpos)));
776 if (((bfd_vma) check & ~reloc_bits) != (-1 & ~reloc_bits))
777 flag = bfd_reloc_overflow;
778 }
779 else
780 flag = bfd_reloc_overflow;
781 }
782 }
783 break;
784 default:
785 abort ();
786 }
787 }
788
789 /*
790 Either we are relocating all the way, or we don't want to apply
791 the relocation to the reloc entry (probably because there isn't
792 any room in the output format to describe addends to relocs)
793 */
794
795 /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
796 (OSF version 1.3, compiler version 3.11). It miscompiles the
797 following program:
798
799 struct str
800 {
801 unsigned int i0;
802 } s = { 0 };
803
804 int
805 main ()
806 {
807 unsigned long x;
808
809 x = 0x100000000;
810 x <<= (unsigned long) s.i0;
811 if (x == 0)
812 printf ("failed\n");
813 else
814 printf ("succeeded (%lx)\n", x);
815 }
816 */
817
818 relocation >>= (bfd_vma) howto->rightshift;
819
820 /* Shift everything up to where it's going to be used */
821
822 relocation <<= (bfd_vma) howto->bitpos;
823
824 /* Wait for the day when all have the mask in them */
825
826 /* What we do:
827 i instruction to be left alone
828 o offset within instruction
829 r relocation offset to apply
830 S src mask
831 D dst mask
832 N ~dst mask
833 A part 1
834 B part 2
835 R result
836
837 Do this:
838 i i i i i o o o o o from bfd_get<size>
839 and S S S S S to get the size offset we want
840 + r r r r r r r r r r to get the final value to place
841 and D D D D D to chop to right size
842 -----------------------
843 A A A A A
844 And this:
845 ... i i i i i o o o o o from bfd_get<size>
846 and N N N N N get instruction
847 -----------------------
848 ... B B B B B
849
850 And then:
851 B B B B B
852 or A A A A A
853 -----------------------
854 R R R R R R R R R R put into bfd_put<size>
855 */
856
857 #define DOIT(x) \
858 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
859
860 switch (howto->size)
861 {
862 case 0:
863 {
864 char x = bfd_get_8 (abfd, (char *) data + addr);
865 DOIT (x);
866 bfd_put_8 (abfd, x, (unsigned char *) data + addr);
867 }
868 break;
869
870 case 1:
871 if (relocation)
872 {
873 short x = bfd_get_16 (abfd, (bfd_byte *) data + addr);
874 DOIT (x);
875 bfd_put_16 (abfd, x, (unsigned char *) data + addr);
876 }
877 break;
878 case 2:
879 if (relocation)
880 {
881 long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
882 DOIT (x);
883 bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
884 }
885 break;
886 case -2:
887 {
888 long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
889 relocation = -relocation;
890 DOIT (x);
891 bfd_put_32 (abfd, x, (bfd_byte *) data + addr);
892 }
893 break;
894
895 case 3:
896 /* Do nothing */
897 break;
898
899 case 4:
900 #ifdef BFD64
901 if (relocation)
902 {
903 bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + addr);
904 DOIT (x);
905 bfd_put_64 (abfd, x, (bfd_byte *) data + addr);
906 }
907 #else
908 abort ();
909 #endif
910 break;
911 default:
912 return bfd_reloc_other;
913 }
914
915 return flag;
916 }
917
918 /* This relocation routine is used by some of the backend linkers.
919 They do not construct asymbol or arelent structures, so there is no
920 reason for them to use bfd_perform_relocation. Also,
921 bfd_perform_relocation is so hacked up it is easier to write a new
922 function than to try to deal with it.
923
924 This routine does a final relocation. It should not be used when
925 generating relocateable output.
926
927 FIXME: This routine ignores any special_function in the HOWTO,
928 since the existing special_function values have been written for
929 bfd_perform_relocation.
930
931 HOWTO is the reloc howto information.
932 INPUT_BFD is the BFD which the reloc applies to.
933 INPUT_SECTION is the section which the reloc applies to.
934 CONTENTS is the contents of the section.
935 ADDRESS is the address of the reloc within INPUT_SECTION.
936 VALUE is the value of the symbol the reloc refers to.
937 ADDEND is the addend of the reloc. */
938
939 bfd_reloc_status_type
940 _bfd_final_link_relocate (howto, input_bfd, input_section, contents, address,
941 value, addend)
942 const reloc_howto_type *howto;
943 bfd *input_bfd;
944 asection *input_section;
945 bfd_byte *contents;
946 bfd_vma address;
947 bfd_vma value;
948 bfd_vma addend;
949 {
950 bfd_vma relocation;
951
952 /* Sanity check the address. */
953 if (address > input_section->_cooked_size)
954 return bfd_reloc_outofrange;
955
956 /* This function assumes that we are dealing with a basic relocation
957 against a symbol. We want to compute the value of the symbol to
958 relocate to. This is just VALUE, the value of the symbol, plus
959 ADDEND, any addend associated with the reloc. */
960 relocation = value + addend;
961
962 /* If the relocation is PC relative, we want to set RELOCATION to
963 the distance between the symbol (currently in RELOCATION) and the
964 location we are relocating. Some targets (e.g., i386-aout)
965 arrange for the contents of the section to be the negative of the
966 offset of the location within the section; for such targets
967 pcrel_offset is false. Other targets (e.g., m88kbcs or ELF)
968 simply leave the contents of the section as zero; for such
969 targets pcrel_offset is true. If pcrel_offset is false we do not
970 need to subtract out the offset of the location within the
971 section (which is just ADDRESS). */
972 if (howto->pc_relative)
973 {
974 relocation -= (input_section->output_section->vma
975 + input_section->output_offset);
976 if (howto->pcrel_offset)
977 relocation -= address;
978 }
979
980 return _bfd_relocate_contents (howto, input_bfd, relocation,
981 contents + address);
982 }
983
984 /* Relocate a given location using a given value and howto. */
985
986 bfd_reloc_status_type
987 _bfd_relocate_contents (howto, input_bfd, relocation, location)
988 const reloc_howto_type *howto;
989 bfd *input_bfd;
990 bfd_vma relocation;
991 bfd_byte *location;
992 {
993 int size;
994 bfd_vma x;
995 boolean overflow;
996
997 /* If the size is negative, negate RELOCATION. This isn't very
998 general. */
999 if (howto->size < 0)
1000 relocation = -relocation;
1001
1002 /* Get the value we are going to relocate. */
1003 size = bfd_get_reloc_size (howto);
1004 switch (size)
1005 {
1006 default:
1007 case 0:
1008 abort ();
1009 case 1:
1010 x = bfd_get_8 (input_bfd, location);
1011 break;
1012 case 2:
1013 x = bfd_get_16 (input_bfd, location);
1014 break;
1015 case 4:
1016 x = bfd_get_32 (input_bfd, location);
1017 break;
1018 case 8:
1019 #ifdef BFD64
1020 x = bfd_get_64 (input_bfd, location);
1021 #else
1022 abort ();
1023 #endif
1024 break;
1025 }
1026
1027 /* Check for overflow. FIXME: We may drop bits during the addition
1028 which we don't check for. We must either check at every single
1029 operation, which would be tedious, or we must do the computations
1030 in a type larger than bfd_vma, which would be inefficient. */
1031 overflow = false;
1032 if (howto->complain_on_overflow != complain_overflow_dont)
1033 {
1034 bfd_vma check;
1035 bfd_signed_vma signed_check;
1036 bfd_vma add;
1037 bfd_signed_vma signed_add;
1038
1039 if (howto->rightshift == 0)
1040 {
1041 check = relocation;
1042 signed_check = (bfd_signed_vma) relocation;
1043 }
1044 else
1045 {
1046 /* Drop unwanted bits from the value we are relocating to. */
1047 check = relocation >> howto->rightshift;
1048
1049 /* If this is a signed value, the rightshift just dropped
1050 leading 1 bits (assuming twos complement). */
1051 if ((bfd_signed_vma) relocation >= 0)
1052 signed_check = check;
1053 else
1054 signed_check = (check
1055 | ((bfd_vma) - 1
1056 & ~((bfd_vma) - 1 >> howto->rightshift)));
1057 }
1058
1059 /* Get the value from the object file. */
1060 add = x & howto->src_mask;
1061
1062 /* Get the value from the object file with an appropriate sign.
1063 The expression involving howto->src_mask isolates the upper
1064 bit of src_mask. If that bit is set in the value we are
1065 adding, it is negative, and we subtract out that number times
1066 two. If src_mask includes the highest possible bit, then we
1067 can not get the upper bit, but that does not matter since
1068 signed_add needs no adjustment to become negative in that
1069 case. */
1070 signed_add = add;
1071 if ((add & (((~howto->src_mask) >> 1) & howto->src_mask)) != 0)
1072 signed_add -= (((~howto->src_mask) >> 1) & howto->src_mask) << 1;
1073
1074 /* Add the value from the object file, shifted so that it is a
1075 straight number. */
1076 if (howto->bitpos == 0)
1077 {
1078 check += add;
1079 signed_check += signed_add;
1080 }
1081 else
1082 {
1083 check += add >> howto->bitpos;
1084
1085 /* For the signed case we use ADD, rather than SIGNED_ADD,
1086 to avoid warnings from SVR4 cc. This is OK since we
1087 explictly handle the sign bits. */
1088 if (signed_add >= 0)
1089 signed_check += add >> howto->bitpos;
1090 else
1091 signed_check += ((add >> howto->bitpos)
1092 | ((bfd_vma) - 1
1093 & ~((bfd_vma) - 1 >> howto->bitpos)));
1094 }
1095
1096 switch (howto->complain_on_overflow)
1097 {
1098 case complain_overflow_signed:
1099 {
1100 /* Assumes two's complement. */
1101 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
1102 bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
1103
1104 if (signed_check > reloc_signed_max
1105 || signed_check < reloc_signed_min)
1106 overflow = true;
1107 }
1108 break;
1109 case complain_overflow_unsigned:
1110 {
1111 /* Assumes two's complement. This expression avoids
1112 overflow if howto->bitsize is the number of bits in
1113 bfd_vma. */
1114 bfd_vma reloc_unsigned_max =
1115 (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
1116
1117 if (check > reloc_unsigned_max)
1118 overflow = true;
1119 }
1120 break;
1121 case complain_overflow_bitfield:
1122 {
1123 /* Assumes two's complement. This expression avoids
1124 overflow if howto->bitsize is the number of bits in
1125 bfd_vma. */
1126 bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
1127
1128 if ((check & ~reloc_bits) != 0
1129 && (((bfd_vma) signed_check & ~reloc_bits)
1130 != (-1 & ~reloc_bits)))
1131 overflow = true;
1132 }
1133 break;
1134 default:
1135 abort ();
1136 }
1137 }
1138
1139 /* Put RELOCATION in the right bits. */
1140 relocation >>= (bfd_vma) howto->rightshift;
1141 relocation <<= (bfd_vma) howto->bitpos;
1142
1143 /* Add RELOCATION to the right bits of X. */
1144 x = ((x & ~howto->dst_mask)
1145 | (((x & howto->src_mask) + relocation) & howto->dst_mask));
1146
1147 /* Put the relocated value back in the object file. */
1148 switch (size)
1149 {
1150 default:
1151 case 0:
1152 abort ();
1153 case 1:
1154 bfd_put_8 (input_bfd, x, location);
1155 break;
1156 case 2:
1157 bfd_put_16 (input_bfd, x, location);
1158 break;
1159 case 4:
1160 bfd_put_32 (input_bfd, x, location);
1161 break;
1162 case 8:
1163 #ifdef BFD64
1164 bfd_put_64 (input_bfd, x, location);
1165 #else
1166 abort ();
1167 #endif
1168 break;
1169 }
1170
1171 return overflow ? bfd_reloc_overflow : bfd_reloc_ok;
1172 }
1173
1174 /*
1175 DOCDD
1176 INODE
1177 howto manager, , typedef arelent, Relocations
1178
1179 SECTION
1180 The howto manager
1181
1182 When an application wants to create a relocation, but doesn't
1183 know what the target machine might call it, it can find out by
1184 using this bit of code.
1185
1186 */
1187
1188 /*
1189 TYPEDEF
1190 bfd_reloc_code_type
1191
1192 DESCRIPTION
1193 The insides of a reloc code. The idea is that, eventually, there
1194 will be one enumerator for every type of relocation we ever do.
1195 Pass one of these values to <<bfd_reloc_type_lookup>>, and it'll
1196 return a howto pointer.
1197
1198 This does mean that the application must determine the correct
1199 enumerator value; you can't get a howto pointer from a random set
1200 of attributes.
1201
1202 CODE_FRAGMENT
1203 .
1204 .typedef enum bfd_reloc_code_real
1205 .{
1206 . {* Basic absolute relocations *}
1207 . BFD_RELOC_64,
1208 . BFD_RELOC_32,
1209 . BFD_RELOC_26,
1210 . BFD_RELOC_16,
1211 . BFD_RELOC_14,
1212 . BFD_RELOC_8,
1213 .
1214 . {* PC-relative relocations *}
1215 . BFD_RELOC_64_PCREL,
1216 . BFD_RELOC_32_PCREL,
1217 . BFD_RELOC_24_PCREL, {* used by i960 *}
1218 . BFD_RELOC_16_PCREL,
1219 . BFD_RELOC_8_PCREL,
1220 .
1221 . {* Linkage-table relative *}
1222 . BFD_RELOC_32_BASEREL,
1223 . BFD_RELOC_16_BASEREL,
1224 . BFD_RELOC_8_BASEREL,
1225 .
1226 . {* The type of reloc used to build a contructor table - at the moment
1227 . probably a 32 bit wide abs address, but the cpu can choose. *}
1228 . BFD_RELOC_CTOR,
1229 .
1230 . {* 8 bits wide, but used to form an address like 0xffnn *}
1231 . BFD_RELOC_8_FFnn,
1232 .
1233 . {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
1234 . word displacement, e.g. for SPARC) *}
1235 . BFD_RELOC_32_PCREL_S2,
1236 . {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
1237 . BFD_RELOC_16_PCREL_S2,
1238 . {* this is used on the Alpha *}
1239 . BFD_RELOC_23_PCREL_S2,
1240 .
1241 . {* High 22 bits of 32-bit value, placed into lower 22 bits of
1242 . target word; simple reloc. *}
1243 . BFD_RELOC_HI22,
1244 . {* Low 10 bits. *}
1245 . BFD_RELOC_LO10,
1246 .
1247 . {* For systems that allocate a Global Pointer register, these are
1248 . displacements off that register. These relocation types are
1249 . handled specially, because the value the register will have is
1250 . decided relatively late. *}
1251 . BFD_RELOC_GPREL16,
1252 . BFD_RELOC_GPREL32,
1253 .
1254 . {* Reloc types used for i960/b.out. *}
1255 . BFD_RELOC_I960_CALLJ,
1256 .
1257 . {* now for the sparc/elf codes *}
1258 . BFD_RELOC_NONE, {* actually used *}
1259 . BFD_RELOC_SPARC_WDISP22,
1260 . BFD_RELOC_SPARC22,
1261 . BFD_RELOC_SPARC13,
1262 . BFD_RELOC_SPARC_GOT10,
1263 . BFD_RELOC_SPARC_GOT13,
1264 . BFD_RELOC_SPARC_GOT22,
1265 . BFD_RELOC_SPARC_PC10,
1266 . BFD_RELOC_SPARC_PC22,
1267 . BFD_RELOC_SPARC_WPLT30,
1268 . BFD_RELOC_SPARC_COPY,
1269 . BFD_RELOC_SPARC_GLOB_DAT,
1270 . BFD_RELOC_SPARC_JMP_SLOT,
1271 . BFD_RELOC_SPARC_RELATIVE,
1272 . BFD_RELOC_SPARC_UA32,
1273 .
1274 . {* these are a.out specific? *}
1275 . BFD_RELOC_SPARC_BASE13,
1276 . BFD_RELOC_SPARC_BASE22,
1277 .
1278 . {* some relocations we're using for sparc v9
1279 . -- subject to change *}
1280 . BFD_RELOC_SPARC_10,
1281 . BFD_RELOC_SPARC_11,
1282 .#define BFD_RELOC_SPARC_64 BFD_RELOC_64
1283 . BFD_RELOC_SPARC_OLO10,
1284 . BFD_RELOC_SPARC_HH22,
1285 . BFD_RELOC_SPARC_HM10,
1286 . BFD_RELOC_SPARC_LM22,
1287 . BFD_RELOC_SPARC_PC_HH22,
1288 . BFD_RELOC_SPARC_PC_HM10,
1289 . BFD_RELOC_SPARC_PC_LM22,
1290 . BFD_RELOC_SPARC_WDISP16,
1291 . BFD_RELOC_SPARC_WDISP19,
1292 . BFD_RELOC_SPARC_GLOB_JMP,
1293 . BFD_RELOC_SPARC_LO7,
1294 .
1295 . {* Alpha ECOFF relocations. Some of these treat the symbol or "addend"
1296 . in some special way. *}
1297 . {* For GPDISP_HI16 ("gpdisp") relocations, the symbol is ignored when
1298 . writing; when reading, it will be the absolute section symbol. The
1299 . addend is the displacement in bytes of the "lda" instruction from
1300 . the "ldah" instruction (which is at the address of this reloc). *}
1301 . BFD_RELOC_ALPHA_GPDISP_HI16,
1302 . {* For GPDISP_LO16 ("ignore") relocations, the symbol is handled as
1303 . with GPDISP_HI16 relocs. The addend is ignored when writing the
1304 . relocations out, and is filled in with the file's GP value on
1305 . reading, for convenience. *}
1306 . BFD_RELOC_ALPHA_GPDISP_LO16,
1307 .
1308 . {* The Alpha LITERAL/LITUSE relocs are produced by a symbol reference;
1309 . the assembler turns it into a LDQ instruction to load the address of
1310 . the symbol, and then fills in a register in the real instruction.
1311 .
1312 . The LITERAL reloc, at the LDQ instruction, refers to the .lita
1313 . section symbol. The addend is ignored when writing, but is filled
1314 . in with the file's GP value on reading, for convenience, as with the
1315 . GPDISP_LO16 reloc.
1316 .
1317 . The LITUSE reloc, on the instruction using the loaded address, gives
1318 . information to the linker that it might be able to use to optimize
1319 . away some literal section references. The symbol is ignored (read
1320 . as the absolute section symbol), and the "addend" indicates the type
1321 . of instruction using the register:
1322 . 1 - "memory" fmt insn
1323 . 2 - byte-manipulation (byte offset reg)
1324 . 3 - jsr (target of branch)
1325 .
1326 . The GNU linker currently doesn't do any of this optimizing. *}
1327 . BFD_RELOC_ALPHA_LITERAL,
1328 . BFD_RELOC_ALPHA_LITUSE,
1329 .
1330 . {* The HINT relocation indicates a value that should be filled into the
1331 . "hint" field of a jmp/jsr/ret instruction, for possible branch-
1332 . prediction logic which may be provided on some processors. *}
1333 . BFD_RELOC_ALPHA_HINT,
1334 .
1335 . {* Bits 27..2 of the relocation address shifted right 2 bits;
1336 . simple reloc otherwise. *}
1337 . BFD_RELOC_MIPS_JMP,
1338 .
1339 . {* High 16 bits of 32-bit value; simple reloc. *}
1340 . BFD_RELOC_HI16,
1341 . {* High 16 bits of 32-bit value but the low 16 bits will be sign
1342 . extended and added to form the final result. If the low 16
1343 . bits form a negative number, we need to add one to the high value
1344 . to compensate for the borrow when the low bits are added. *}
1345 . BFD_RELOC_HI16_S,
1346 . {* Low 16 bits. *}
1347 . BFD_RELOC_LO16,
1348 . {* Like BFD_RELOC_HI16_S, but PC relative. *}
1349 . BFD_RELOC_PCREL_HI16_S,
1350 . {* Like BFD_RELOC_LO16, but PC relative. *}
1351 . BFD_RELOC_PCREL_LO16,
1352 .
1353 . {* relocation relative to the global pointer. *}
1354 .#define BFD_RELOC_MIPS_GPREL BFD_RELOC_GPREL16
1355 .
1356 . {* Relocation against a MIPS literal section. *}
1357 . BFD_RELOC_MIPS_LITERAL,
1358 .
1359 . {* MIPS ELF relocations. *}
1360 . BFD_RELOC_MIPS_GOT16,
1361 . BFD_RELOC_MIPS_CALL16,
1362 .#define BFD_RELOC_MIPS_GPREL32 BFD_RELOC_GPREL32
1363 .
1364 . {* i386/elf relocations *}
1365 . BFD_RELOC_386_GOT32,
1366 . BFD_RELOC_386_PLT32,
1367 . BFD_RELOC_386_COPY,
1368 . BFD_RELOC_386_GLOB_DAT,
1369 . BFD_RELOC_386_JUMP_SLOT,
1370 . BFD_RELOC_386_RELATIVE,
1371 . BFD_RELOC_386_GOTOFF,
1372 . BFD_RELOC_386_GOTPC,
1373 .
1374 . {* PowerPC/POWER (RS/6000) relocs. *}
1375 . {* 26 bit relative branch. Low two bits must be zero. High 24
1376 . bits installed in bits 6 through 29 of instruction. *}
1377 . BFD_RELOC_PPC_B26,
1378 . {* 26 bit absolute branch, like BFD_RELOC_PPC_B26 but absolute. *}
1379 . BFD_RELOC_PPC_BA26,
1380 . {* 16 bit TOC relative reference. *}
1381 . BFD_RELOC_PPC_TOC16,
1382 .
1383 . {* this must be the highest numeric value *}
1384 . BFD_RELOC_UNUSED
1385 . } bfd_reloc_code_real_type;
1386 */
1387
1388
1389 /*
1390 FUNCTION
1391 bfd_reloc_type_lookup
1392
1393 SYNOPSIS
1394 const struct reloc_howto_struct *
1395 bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
1396
1397 DESCRIPTION
1398 Return a pointer to a howto structure which, when
1399 invoked, will perform the relocation @var{code} on data from the
1400 architecture noted.
1401
1402 */
1403
1404
1405 const struct reloc_howto_struct *
1406 bfd_reloc_type_lookup (abfd, code)
1407 bfd *abfd;
1408 bfd_reloc_code_real_type code;
1409 {
1410 return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
1411 }
1412
1413 static reloc_howto_type bfd_howto_32 =
1414 HOWTO (0, 00, 2, 32, false, 0, complain_overflow_bitfield, 0, "VRT32", false, 0xffffffff, 0xffffffff, true);
1415
1416
1417 /*
1418 INTERNAL_FUNCTION
1419 bfd_default_reloc_type_lookup
1420
1421 SYNOPSIS
1422 const struct reloc_howto_struct *bfd_default_reloc_type_lookup
1423 (bfd *abfd, bfd_reloc_code_real_type code);
1424
1425 DESCRIPTION
1426 Provides a default relocation lookup routine for any architecture.
1427
1428
1429 */
1430
1431 const struct reloc_howto_struct *
1432 bfd_default_reloc_type_lookup (abfd, code)
1433 bfd *abfd;
1434 bfd_reloc_code_real_type code;
1435 {
1436 switch (code)
1437 {
1438 case BFD_RELOC_CTOR:
1439 /* The type of reloc used in a ctor, which will be as wide as the
1440 address - so either a 64, 32, or 16 bitter. */
1441 switch (bfd_get_arch_info (abfd)->bits_per_address)
1442 {
1443 case 64:
1444 BFD_FAIL ();
1445 case 32:
1446 return &bfd_howto_32;
1447 case 16:
1448 BFD_FAIL ();
1449 default:
1450 BFD_FAIL ();
1451 }
1452 default:
1453 BFD_FAIL ();
1454 }
1455 return (const struct reloc_howto_struct *) NULL;
1456 }
1457
1458
1459 /*
1460 INTERNAL_FUNCTION
1461 bfd_generic_relax_section
1462
1463 SYNOPSIS
1464 boolean bfd_generic_relax_section
1465 (bfd *abfd,
1466 asection *section,
1467 struct bfd_link_info *,
1468 boolean *);
1469
1470 DESCRIPTION
1471 Provides default handling for relaxing for back ends which
1472 don't do relaxing -- i.e., does nothing.
1473 */
1474
1475 /*ARGSUSED*/
1476 boolean
1477 bfd_generic_relax_section (abfd, section, link_info, again)
1478 bfd *abfd;
1479 asection *section;
1480 struct bfd_link_info *link_info;
1481 boolean *again;
1482 {
1483 *again = false;
1484 return true;
1485 }
1486
1487 /*
1488 INTERNAL_FUNCTION
1489 bfd_generic_get_relocated_section_contents
1490
1491 SYNOPSIS
1492 bfd_byte *
1493 bfd_generic_get_relocated_section_contents (bfd *abfd,
1494 struct bfd_link_info *link_info,
1495 struct bfd_link_order *link_order,
1496 bfd_byte *data,
1497 boolean relocateable,
1498 asymbol **symbols);
1499
1500 DESCRIPTION
1501 Provides default handling of relocation effort for back ends
1502 which can't be bothered to do it efficiently.
1503
1504 */
1505
1506 bfd_byte *
1507 bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data,
1508 relocateable, symbols)
1509 bfd *abfd;
1510 struct bfd_link_info *link_info;
1511 struct bfd_link_order *link_order;
1512 bfd_byte *data;
1513 boolean relocateable;
1514 asymbol **symbols;
1515 {
1516 /* Get enough memory to hold the stuff */
1517 bfd *input_bfd = link_order->u.indirect.section->owner;
1518 asection *input_section = link_order->u.indirect.section;
1519
1520 long reloc_size = bfd_get_reloc_upper_bound (input_bfd, input_section);
1521 arelent **reloc_vector = NULL;
1522 long reloc_count;
1523
1524 if (reloc_size < 0)
1525 goto error_return;
1526
1527 reloc_vector = (arelent **) malloc (reloc_size);
1528 if (reloc_vector == NULL && reloc_size != 0)
1529 {
1530 bfd_set_error (bfd_error_no_memory);
1531 goto error_return;
1532 }
1533
1534 /* read in the section */
1535 if (!bfd_get_section_contents (input_bfd,
1536 input_section,
1537 (PTR) data,
1538 0,
1539 input_section->_raw_size))
1540 goto error_return;
1541
1542 /* We're not relaxing the section, so just copy the size info */
1543 input_section->_cooked_size = input_section->_raw_size;
1544 input_section->reloc_done = true;
1545
1546 reloc_count = bfd_canonicalize_reloc (input_bfd,
1547 input_section,
1548 reloc_vector,
1549 symbols);
1550 if (reloc_count < 0)
1551 goto error_return;
1552
1553 if (reloc_count > 0)
1554 {
1555 arelent **parent;
1556 for (parent = reloc_vector; *parent != (arelent *) NULL;
1557 parent++)
1558 {
1559 char *error_message = (char *) NULL;
1560 bfd_reloc_status_type r =
1561 bfd_perform_relocation (input_bfd,
1562 *parent,
1563 (PTR) data,
1564 input_section,
1565 relocateable ? abfd : (bfd *) NULL,
1566 &error_message);
1567
1568 if (relocateable)
1569 {
1570 asection *os = input_section->output_section;
1571
1572 /* A partial link, so keep the relocs */
1573 os->orelocation[os->reloc_count] = *parent;
1574 os->reloc_count++;
1575 }
1576
1577 if (r != bfd_reloc_ok)
1578 {
1579 switch (r)
1580 {
1581 case bfd_reloc_undefined:
1582 if (!((*link_info->callbacks->undefined_symbol)
1583 (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
1584 input_bfd, input_section, (*parent)->address)))
1585 goto error_return;
1586 break;
1587 case bfd_reloc_dangerous:
1588 BFD_ASSERT (error_message != (char *) NULL);
1589 if (!((*link_info->callbacks->reloc_dangerous)
1590 (link_info, error_message, input_bfd, input_section,
1591 (*parent)->address)))
1592 goto error_return;
1593 break;
1594 case bfd_reloc_overflow:
1595 if (!((*link_info->callbacks->reloc_overflow)
1596 (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
1597 (*parent)->howto->name, (*parent)->addend,
1598 input_bfd, input_section, (*parent)->address)))
1599 goto error_return;
1600 break;
1601 case bfd_reloc_outofrange:
1602 default:
1603 abort ();
1604 break;
1605 }
1606
1607 }
1608 }
1609 }
1610 if (reloc_vector != NULL)
1611 free (reloc_vector);
1612 return data;
1613
1614 error_return:
1615 if (reloc_vector != NULL)
1616 free (reloc_vector);
1617 return NULL;
1618 }
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