Add OpenRISC support
[binutils.git] / bfd / reloc.c
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1 /* BFD support for handling relocation entries.
2 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001
4 Free Software Foundation, Inc.
5 Written by Cygnus Support.
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
24 SECTION
25 Relocations
27 BFD maintains relocations in much the same way it maintains
28 symbols: they are left alone until required, then read in
29 en-masse and translated into an internal form. A common
30 routine <<bfd_perform_relocation>> acts upon the
31 canonical form to do the fixup.
33 Relocations are maintained on a per section basis,
34 while symbols are maintained on a per BFD basis.
36 All that a back end has to do to fit the BFD interface is to create
37 a <<struct reloc_cache_entry>> for each relocation
38 in a particular section, and fill in the right bits of the structures.
40 @menu
41 @* typedef arelent::
42 @* howto manager::
43 @end menu
47 /* DO compile in the reloc_code name table from libbfd.h. */
48 #define _BFD_MAKE_TABLE_bfd_reloc_code_real
50 #include "bfd.h"
51 #include "sysdep.h"
52 #include "bfdlink.h"
53 #include "libbfd.h"
55 DOCDD
56 INODE
57 typedef arelent, howto manager, Relocations, Relocations
59 SUBSECTION
60 typedef arelent
62 This is the structure of a relocation entry:
64 CODE_FRAGMENT
66 .typedef enum bfd_reloc_status
68 . {* No errors detected *}
69 . bfd_reloc_ok,
71 . {* The relocation was performed, but there was an overflow. *}
72 . bfd_reloc_overflow,
74 . {* The address to relocate was not within the section supplied. *}
75 . bfd_reloc_outofrange,
77 . {* Used by special functions *}
78 . bfd_reloc_continue,
80 . {* Unsupported relocation size requested. *}
81 . bfd_reloc_notsupported,
83 . {* Unused *}
84 . bfd_reloc_other,
86 . {* The symbol to relocate against was undefined. *}
87 . bfd_reloc_undefined,
89 . {* The relocation was performed, but may not be ok - presently
90 . generated only when linking i960 coff files with i960 b.out
91 . symbols. If this type is returned, the error_message argument
92 . to bfd_perform_relocation will be set. *}
93 . bfd_reloc_dangerous
94 . }
95 . bfd_reloc_status_type;
98 .typedef struct reloc_cache_entry
100 . {* A pointer into the canonical table of pointers *}
101 . struct symbol_cache_entry **sym_ptr_ptr;
103 . {* offset in section *}
104 . bfd_size_type address;
106 . {* addend for relocation value *}
107 . bfd_vma addend;
109 . {* Pointer to how to perform the required relocation *}
110 . reloc_howto_type *howto;
112 .} arelent;
117 DESCRIPTION
119 Here is a description of each of the fields within an <<arelent>>:
121 o <<sym_ptr_ptr>>
123 The symbol table pointer points to a pointer to the symbol
124 associated with the relocation request. It is
125 the pointer into the table returned by the back end's
126 <<get_symtab>> action. @xref{Symbols}. The symbol is referenced
127 through a pointer to a pointer so that tools like the linker
128 can fix up all the symbols of the same name by modifying only
129 one pointer. The relocation routine looks in the symbol and
130 uses the base of the section the symbol is attached to and the
131 value of the symbol as the initial relocation offset. If the
132 symbol pointer is zero, then the section provided is looked up.
134 o <<address>>
136 The <<address>> field gives the offset in bytes from the base of
137 the section data which owns the relocation record to the first
138 byte of relocatable information. The actual data relocated
139 will be relative to this point; for example, a relocation
140 type which modifies the bottom two bytes of a four byte word
141 would not touch the first byte pointed to in a big endian
142 world.
144 o <<addend>>
146 The <<addend>> is a value provided by the back end to be added (!)
147 to the relocation offset. Its interpretation is dependent upon
148 the howto. For example, on the 68k the code:
150 | char foo[];
151 | main()
153 | return foo[0x12345678];
156 Could be compiled into:
158 | linkw fp,#-4
159 | moveb @@#12345678,d0
160 | extbl d0
161 | unlk fp
162 | rts
164 This could create a reloc pointing to <<foo>>, but leave the
165 offset in the data, something like:
167 |RELOCATION RECORDS FOR [.text]:
168 |offset type value
169 |00000006 32 _foo
171 |00000000 4e56 fffc ; linkw fp,#-4
172 |00000004 1039 1234 5678 ; moveb @@#12345678,d0
173 |0000000a 49c0 ; extbl d0
174 |0000000c 4e5e ; unlk fp
175 |0000000e 4e75 ; rts
177 Using coff and an 88k, some instructions don't have enough
178 space in them to represent the full address range, and
179 pointers have to be loaded in two parts. So you'd get something like:
181 | or.u r13,r0,hi16(_foo+0x12345678)
182 | ld.b r2,r13,lo16(_foo+0x12345678)
183 | jmp r1
185 This should create two relocs, both pointing to <<_foo>>, and with
186 0x12340000 in their addend field. The data would consist of:
188 |RELOCATION RECORDS FOR [.text]:
189 |offset type value
190 |00000002 HVRT16 _foo+0x12340000
191 |00000006 LVRT16 _foo+0x12340000
193 |00000000 5da05678 ; or.u r13,r0,0x5678
194 |00000004 1c4d5678 ; ld.b r2,r13,0x5678
195 |00000008 f400c001 ; jmp r1
197 The relocation routine digs out the value from the data, adds
198 it to the addend to get the original offset, and then adds the
199 value of <<_foo>>. Note that all 32 bits have to be kept around
200 somewhere, to cope with carry from bit 15 to bit 16.
202 One further example is the sparc and the a.out format. The
203 sparc has a similar problem to the 88k, in that some
204 instructions don't have room for an entire offset, but on the
205 sparc the parts are created in odd sized lumps. The designers of
206 the a.out format chose to not use the data within the section
207 for storing part of the offset; all the offset is kept within
208 the reloc. Anything in the data should be ignored.
210 | save %sp,-112,%sp
211 | sethi %hi(_foo+0x12345678),%g2
212 | ldsb [%g2+%lo(_foo+0x12345678)],%i0
213 | ret
214 | restore
216 Both relocs contain a pointer to <<foo>>, and the offsets
217 contain junk.
219 |RELOCATION RECORDS FOR [.text]:
220 |offset type value
221 |00000004 HI22 _foo+0x12345678
222 |00000008 LO10 _foo+0x12345678
224 |00000000 9de3bf90 ; save %sp,-112,%sp
225 |00000004 05000000 ; sethi %hi(_foo+0),%g2
226 |00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0
227 |0000000c 81c7e008 ; ret
228 |00000010 81e80000 ; restore
230 o <<howto>>
232 The <<howto>> field can be imagined as a
233 relocation instruction. It is a pointer to a structure which
234 contains information on what to do with all of the other
235 information in the reloc record and data section. A back end
236 would normally have a relocation instruction set and turn
237 relocations into pointers to the correct structure on input -
238 but it would be possible to create each howto field on demand.
243 SUBSUBSECTION
244 <<enum complain_overflow>>
246 Indicates what sort of overflow checking should be done when
247 performing a relocation.
249 CODE_FRAGMENT
251 .enum complain_overflow
253 . {* Do not complain on overflow. *}
254 . complain_overflow_dont,
256 . {* Complain if the bitfield overflows, whether it is considered
257 . as signed or unsigned. *}
258 . complain_overflow_bitfield,
260 . {* Complain if the value overflows when considered as signed
261 . number. *}
262 . complain_overflow_signed,
264 . {* Complain if the value overflows when considered as an
265 . unsigned number. *}
266 . complain_overflow_unsigned
272 SUBSUBSECTION
273 <<reloc_howto_type>>
275 The <<reloc_howto_type>> is a structure which contains all the
276 information that libbfd needs to know to tie up a back end's data.
278 CODE_FRAGMENT
279 .struct symbol_cache_entry; {* Forward declaration *}
281 .struct reloc_howto_struct
283 . {* The type field has mainly a documentary use - the back end can
284 . do what it wants with it, though normally the back end's
285 . external idea of what a reloc number is stored
286 . in this field. For example, a PC relative word relocation
287 . in a coff environment has the type 023 - because that's
288 . what the outside world calls a R_PCRWORD reloc. *}
289 . unsigned int type;
291 . {* The value the final relocation is shifted right by. This drops
292 . unwanted data from the relocation. *}
293 . unsigned int rightshift;
295 . {* The size of the item to be relocated. This is *not* a
296 . power-of-two measure. To get the number of bytes operated
297 . on by a type of relocation, use bfd_get_reloc_size. *}
298 . int size;
300 . {* The number of bits in the item to be relocated. This is used
301 . when doing overflow checking. *}
302 . unsigned int bitsize;
304 . {* Notes that the relocation is relative to the location in the
305 . data section of the addend. The relocation function will
306 . subtract from the relocation value the address of the location
307 . being relocated. *}
308 . boolean pc_relative;
310 . {* The bit position of the reloc value in the destination.
311 . The relocated value is left shifted by this amount. *}
312 . unsigned int bitpos;
314 . {* What type of overflow error should be checked for when
315 . relocating. *}
316 . enum complain_overflow complain_on_overflow;
318 . {* If this field is non null, then the supplied function is
319 . called rather than the normal function. This allows really
320 . strange relocation methods to be accomodated (e.g., i960 callj
321 . instructions). *}
322 . bfd_reloc_status_type (*special_function)
323 . PARAMS ((bfd *abfd,
324 . arelent *reloc_entry,
325 . struct symbol_cache_entry *symbol,
326 . PTR data,
327 . asection *input_section,
328 . bfd *output_bfd,
329 . char **error_message));
331 . {* The textual name of the relocation type. *}
332 . char *name;
334 . {* Some formats record a relocation addend in the section contents
335 . rather than with the relocation. For ELF formats this is the
336 . distinction between USE_REL and USE_RELA (though the code checks
337 . for USE_REL == 1/0). The value of this field is TRUE if the
338 . addend is recorded with the section contents; when performing a
339 . partial link (ld -r) the section contents (the data) will be
340 . modified. The value of this field is FALSE if addends are
341 . recorded with the relocation (in arelent.addend); when performing
342 . a partial link the relocation will be modified.
343 . All relocations for all ELF USE_RELA targets should set this field
344 . to FALSE (values of TRUE should be looked on with suspicion).
345 . However, the converse is not true: not all relocations of all ELF
346 . USE_REL targets set this field to TRUE. Why this is so is peculiar
347 . to each particular target. For relocs that aren't used in partial
348 . links (e.g. GOT stuff) it doesn't matter what this is set to. *}
349 . boolean partial_inplace;
351 . {* The src_mask selects which parts of the read in data
352 . are to be used in the relocation sum. E.g., if this was an 8 bit
353 . byte of data which we read and relocated, this would be
354 . 0x000000ff. When we have relocs which have an addend, such as
355 . sun4 extended relocs, the value in the offset part of a
356 . relocating field is garbage so we never use it. In this case
357 . the mask would be 0x00000000. *}
358 . bfd_vma src_mask;
360 . {* The dst_mask selects which parts of the instruction are replaced
361 . into the instruction. In most cases src_mask == dst_mask,
362 . except in the above special case, where dst_mask would be
363 . 0x000000ff, and src_mask would be 0x00000000. *}
364 . bfd_vma dst_mask;
366 . {* When some formats create PC relative instructions, they leave
367 . the value of the pc of the place being relocated in the offset
368 . slot of the instruction, so that a PC relative relocation can
369 . be made just by adding in an ordinary offset (e.g., sun3 a.out).
370 . Some formats leave the displacement part of an instruction
371 . empty (e.g., m88k bcs); this flag signals the fact.*}
372 . boolean pcrel_offset;
379 FUNCTION
380 The HOWTO Macro
382 DESCRIPTION
383 The HOWTO define is horrible and will go away.
385 .#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
386 . {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
388 DESCRIPTION
389 And will be replaced with the totally magic way. But for the
390 moment, we are compatible, so do it this way.
392 .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
395 DESCRIPTION
396 This is used to fill in an empty howto entry in an array.
398 .#define EMPTY_HOWTO(C) \
399 . HOWTO((C),0,0,0,false,0,complain_overflow_dont,NULL,NULL,false,0,0,false)
402 DESCRIPTION
403 Helper routine to turn a symbol into a relocation value.
405 .#define HOWTO_PREPARE(relocation, symbol) \
406 . { \
407 . if (symbol != (asymbol *)NULL) { \
408 . if (bfd_is_com_section (symbol->section)) { \
409 . relocation = 0; \
410 . } \
411 . else { \
412 . relocation = symbol->value; \
413 . } \
414 . } \
420 FUNCTION
421 bfd_get_reloc_size
423 SYNOPSIS
424 unsigned int bfd_get_reloc_size (reloc_howto_type *);
426 DESCRIPTION
427 For a reloc_howto_type that operates on a fixed number of bytes,
428 this returns the number of bytes operated on.
431 unsigned int
432 bfd_get_reloc_size (howto)
433 reloc_howto_type *howto;
435 switch (howto->size)
437 case 0: return 1;
438 case 1: return 2;
439 case 2: return 4;
440 case 3: return 0;
441 case 4: return 8;
442 case 8: return 16;
443 case -2: return 4;
444 default: abort ();
449 TYPEDEF
450 arelent_chain
452 DESCRIPTION
454 How relocs are tied together in an <<asection>>:
456 .typedef struct relent_chain {
457 . arelent relent;
458 . struct relent_chain *next;
459 .} arelent_chain;
463 /* N_ONES produces N one bits, without overflowing machine arithmetic. */
464 #define N_ONES(n) (((((bfd_vma) 1 << ((n) - 1)) - 1) << 1) | 1)
467 FUNCTION
468 bfd_check_overflow
470 SYNOPSIS
471 bfd_reloc_status_type
472 bfd_check_overflow
473 (enum complain_overflow how,
474 unsigned int bitsize,
475 unsigned int rightshift,
476 unsigned int addrsize,
477 bfd_vma relocation);
479 DESCRIPTION
480 Perform overflow checking on @var{relocation} which has
481 @var{bitsize} significant bits and will be shifted right by
482 @var{rightshift} bits, on a machine with addresses containing
483 @var{addrsize} significant bits. The result is either of
484 @code{bfd_reloc_ok} or @code{bfd_reloc_overflow}.
488 bfd_reloc_status_type
489 bfd_check_overflow (how, bitsize, rightshift, addrsize, relocation)
490 enum complain_overflow how;
491 unsigned int bitsize;
492 unsigned int rightshift;
493 unsigned int addrsize;
494 bfd_vma relocation;
496 bfd_vma fieldmask, addrmask, signmask, ss, a;
497 bfd_reloc_status_type flag = bfd_reloc_ok;
499 a = relocation;
501 /* Note: BITSIZE should always be <= ADDRSIZE, but in case it's not,
502 we'll be permissive: extra bits in the field mask will
503 automatically extend the address mask for purposes of the
504 overflow check. */
505 fieldmask = N_ONES (bitsize);
506 addrmask = N_ONES (addrsize) | fieldmask;
508 switch (how)
510 case complain_overflow_dont:
511 break;
513 case complain_overflow_signed:
514 /* If any sign bits are set, all sign bits must be set. That
515 is, A must be a valid negative address after shifting. */
516 a = (a & addrmask) >> rightshift;
517 signmask = ~ (fieldmask >> 1);
518 ss = a & signmask;
519 if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
520 flag = bfd_reloc_overflow;
521 break;
523 case complain_overflow_unsigned:
524 /* We have an overflow if the address does not fit in the field. */
525 a = (a & addrmask) >> rightshift;
526 if ((a & ~ fieldmask) != 0)
527 flag = bfd_reloc_overflow;
528 break;
530 case complain_overflow_bitfield:
531 /* Bitfields are sometimes signed, sometimes unsigned. We
532 explicitly allow an address wrap too, which means a bitfield
533 of n bits is allowed to store -2**n to 2**n-1. Thus overflow
534 if the value has some, but not all, bits set outside the
535 field. */
536 a >>= rightshift;
537 ss = a & ~ fieldmask;
538 if (ss != 0 && ss != (((bfd_vma) -1 >> rightshift) & ~ fieldmask))
539 flag = bfd_reloc_overflow;
540 break;
542 default:
543 abort ();
546 return flag;
550 FUNCTION
551 bfd_perform_relocation
553 SYNOPSIS
554 bfd_reloc_status_type
555 bfd_perform_relocation
556 (bfd *abfd,
557 arelent *reloc_entry,
558 PTR data,
559 asection *input_section,
560 bfd *output_bfd,
561 char **error_message);
563 DESCRIPTION
564 If @var{output_bfd} is supplied to this function, the
565 generated image will be relocatable; the relocations are
566 copied to the output file after they have been changed to
567 reflect the new state of the world. There are two ways of
568 reflecting the results of partial linkage in an output file:
569 by modifying the output data in place, and by modifying the
570 relocation record. Some native formats (e.g., basic a.out and
571 basic coff) have no way of specifying an addend in the
572 relocation type, so the addend has to go in the output data.
573 This is no big deal since in these formats the output data
574 slot will always be big enough for the addend. Complex reloc
575 types with addends were invented to solve just this problem.
576 The @var{error_message} argument is set to an error message if
577 this return @code{bfd_reloc_dangerous}.
581 bfd_reloc_status_type
582 bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd,
583 error_message)
584 bfd *abfd;
585 arelent *reloc_entry;
586 PTR data;
587 asection *input_section;
588 bfd *output_bfd;
589 char **error_message;
591 bfd_vma relocation;
592 bfd_reloc_status_type flag = bfd_reloc_ok;
593 bfd_size_type octets = reloc_entry->address * bfd_octets_per_byte (abfd);
594 bfd_vma output_base = 0;
595 reloc_howto_type *howto = reloc_entry->howto;
596 asection *reloc_target_output_section;
597 asymbol *symbol;
599 symbol = *(reloc_entry->sym_ptr_ptr);
600 if (bfd_is_abs_section (symbol->section)
601 && output_bfd != (bfd *) NULL)
603 reloc_entry->address += input_section->output_offset;
604 return bfd_reloc_ok;
607 /* If we are not producing relocateable output, return an error if
608 the symbol is not defined. An undefined weak symbol is
609 considered to have a value of zero (SVR4 ABI, p. 4-27). */
610 if (bfd_is_und_section (symbol->section)
611 && (symbol->flags & BSF_WEAK) == 0
612 && output_bfd == (bfd *) NULL)
613 flag = bfd_reloc_undefined;
615 /* If there is a function supplied to handle this relocation type,
616 call it. It'll return `bfd_reloc_continue' if further processing
617 can be done. */
618 if (howto->special_function)
620 bfd_reloc_status_type cont;
621 cont = howto->special_function (abfd, reloc_entry, symbol, data,
622 input_section, output_bfd,
623 error_message);
624 if (cont != bfd_reloc_continue)
625 return cont;
628 /* Is the address of the relocation really within the section? */
629 if (reloc_entry->address > input_section->_cooked_size /
630 bfd_octets_per_byte (abfd))
631 return bfd_reloc_outofrange;
633 /* Work out which section the relocation is targetted at and the
634 initial relocation command value. */
636 /* Get symbol value. (Common symbols are special.) */
637 if (bfd_is_com_section (symbol->section))
638 relocation = 0;
639 else
640 relocation = symbol->value;
642 reloc_target_output_section = symbol->section->output_section;
644 /* Convert input-section-relative symbol value to absolute. */
645 if (output_bfd && howto->partial_inplace == false)
646 output_base = 0;
647 else
648 output_base = reloc_target_output_section->vma;
650 relocation += output_base + symbol->section->output_offset;
652 /* Add in supplied addend. */
653 relocation += reloc_entry->addend;
655 /* Here the variable relocation holds the final address of the
656 symbol we are relocating against, plus any addend. */
658 if (howto->pc_relative == true)
660 /* This is a PC relative relocation. We want to set RELOCATION
661 to the distance between the address of the symbol and the
662 location. RELOCATION is already the address of the symbol.
664 We start by subtracting the address of the section containing
665 the location.
667 If pcrel_offset is set, we must further subtract the position
668 of the location within the section. Some targets arrange for
669 the addend to be the negative of the position of the location
670 within the section; for example, i386-aout does this. For
671 i386-aout, pcrel_offset is false. Some other targets do not
672 include the position of the location; for example, m88kbcs,
673 or ELF. For those targets, pcrel_offset is true.
675 If we are producing relocateable output, then we must ensure
676 that this reloc will be correctly computed when the final
677 relocation is done. If pcrel_offset is false we want to wind
678 up with the negative of the location within the section,
679 which means we must adjust the existing addend by the change
680 in the location within the section. If pcrel_offset is true
681 we do not want to adjust the existing addend at all.
683 FIXME: This seems logical to me, but for the case of
684 producing relocateable output it is not what the code
685 actually does. I don't want to change it, because it seems
686 far too likely that something will break. */
688 relocation -=
689 input_section->output_section->vma + input_section->output_offset;
691 if (howto->pcrel_offset == true)
692 relocation -= reloc_entry->address;
695 if (output_bfd != (bfd *) NULL)
697 if (howto->partial_inplace == false)
699 /* This is a partial relocation, and we want to apply the relocation
700 to the reloc entry rather than the raw data. Modify the reloc
701 inplace to reflect what we now know. */
702 reloc_entry->addend = relocation;
703 reloc_entry->address += input_section->output_offset;
704 return flag;
706 else
708 /* This is a partial relocation, but inplace, so modify the
709 reloc record a bit.
711 If we've relocated with a symbol with a section, change
712 into a ref to the section belonging to the symbol. */
714 reloc_entry->address += input_section->output_offset;
716 /* WTF?? */
717 if (abfd->xvec->flavour == bfd_target_coff_flavour
718 && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
719 && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
721 #if 1
722 /* For m68k-coff, the addend was being subtracted twice during
723 relocation with -r. Removing the line below this comment
724 fixes that problem; see PR 2953.
726 However, Ian wrote the following, regarding removing the line below,
727 which explains why it is still enabled: --djm
729 If you put a patch like that into BFD you need to check all the COFF
730 linkers. I am fairly certain that patch will break coff-i386 (e.g.,
731 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
732 problem in a different way. There may very well be a reason that the
733 code works as it does.
735 Hmmm. The first obvious point is that bfd_perform_relocation should
736 not have any tests that depend upon the flavour. It's seem like
737 entirely the wrong place for such a thing. The second obvious point
738 is that the current code ignores the reloc addend when producing
739 relocateable output for COFF. That's peculiar. In fact, I really
740 have no idea what the point of the line you want to remove is.
742 A typical COFF reloc subtracts the old value of the symbol and adds in
743 the new value to the location in the object file (if it's a pc
744 relative reloc it adds the difference between the symbol value and the
745 location). When relocating we need to preserve that property.
747 BFD handles this by setting the addend to the negative of the old
748 value of the symbol. Unfortunately it handles common symbols in a
749 non-standard way (it doesn't subtract the old value) but that's a
750 different story (we can't change it without losing backward
751 compatibility with old object files) (coff-i386 does subtract the old
752 value, to be compatible with existing coff-i386 targets, like SCO).
754 So everything works fine when not producing relocateable output. When
755 we are producing relocateable output, logically we should do exactly
756 what we do when not producing relocateable output. Therefore, your
757 patch is correct. In fact, it should probably always just set
758 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
759 add the value into the object file. This won't hurt the COFF code,
760 which doesn't use the addend; I'm not sure what it will do to other
761 formats (the thing to check for would be whether any formats both use
762 the addend and set partial_inplace).
764 When I wanted to make coff-i386 produce relocateable output, I ran
765 into the problem that you are running into: I wanted to remove that
766 line. Rather than risk it, I made the coff-i386 relocs use a special
767 function; it's coff_i386_reloc in coff-i386.c. The function
768 specifically adds the addend field into the object file, knowing that
769 bfd_perform_relocation is not going to. If you remove that line, then
770 coff-i386.c will wind up adding the addend field in twice. It's
771 trivial to fix; it just needs to be done.
773 The problem with removing the line is just that it may break some
774 working code. With BFD it's hard to be sure of anything. The right
775 way to deal with this is simply to build and test at least all the
776 supported COFF targets. It should be straightforward if time and disk
777 space consuming. For each target:
778 1) build the linker
779 2) generate some executable, and link it using -r (I would
780 probably use paranoia.o and link against newlib/libc.a, which
781 for all the supported targets would be available in
782 /usr/cygnus/progressive/H-host/target/lib/libc.a).
783 3) make the change to reloc.c
784 4) rebuild the linker
785 5) repeat step 2
786 6) if the resulting object files are the same, you have at least
787 made it no worse
788 7) if they are different you have to figure out which version is
789 right
791 relocation -= reloc_entry->addend;
792 #endif
793 reloc_entry->addend = 0;
795 else
797 reloc_entry->addend = relocation;
801 else
803 reloc_entry->addend = 0;
806 /* FIXME: This overflow checking is incomplete, because the value
807 might have overflowed before we get here. For a correct check we
808 need to compute the value in a size larger than bitsize, but we
809 can't reasonably do that for a reloc the same size as a host
810 machine word.
811 FIXME: We should also do overflow checking on the result after
812 adding in the value contained in the object file. */
813 if (howto->complain_on_overflow != complain_overflow_dont
814 && flag == bfd_reloc_ok)
815 flag = bfd_check_overflow (howto->complain_on_overflow,
816 howto->bitsize,
817 howto->rightshift,
818 bfd_arch_bits_per_address (abfd),
819 relocation);
822 Either we are relocating all the way, or we don't want to apply
823 the relocation to the reloc entry (probably because there isn't
824 any room in the output format to describe addends to relocs)
827 /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
828 (OSF version 1.3, compiler version 3.11). It miscompiles the
829 following program:
831 struct str
833 unsigned int i0;
834 } s = { 0 };
837 main ()
839 unsigned long x;
841 x = 0x100000000;
842 x <<= (unsigned long) s.i0;
843 if (x == 0)
844 printf ("failed\n");
845 else
846 printf ("succeeded (%lx)\n", x);
850 relocation >>= (bfd_vma) howto->rightshift;
852 /* Shift everything up to where it's going to be used */
854 relocation <<= (bfd_vma) howto->bitpos;
856 /* Wait for the day when all have the mask in them */
858 /* What we do:
859 i instruction to be left alone
860 o offset within instruction
861 r relocation offset to apply
862 S src mask
863 D dst mask
864 N ~dst mask
865 A part 1
866 B part 2
867 R result
869 Do this:
870 (( i i i i i o o o o o from bfd_get<size>
871 and S S S S S) to get the size offset we want
872 + r r r r r r r r r r) to get the final value to place
873 and D D D D D to chop to right size
874 -----------------------
875 = A A A A A
876 And this:
877 ( i i i i i o o o o o from bfd_get<size>
878 and N N N N N ) get instruction
879 -----------------------
880 = B B B B B
882 And then:
883 ( B B B B B
884 or A A A A A)
885 -----------------------
886 = R R R R R R R R R R put into bfd_put<size>
889 #define DOIT(x) \
890 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
892 switch (howto->size)
894 case 0:
896 char x = bfd_get_8 (abfd, (char *) data + octets);
897 DOIT (x);
898 bfd_put_8 (abfd, x, (unsigned char *) data + octets);
900 break;
902 case 1:
904 short x = bfd_get_16 (abfd, (bfd_byte *) data + octets);
905 DOIT (x);
906 bfd_put_16 (abfd, x, (unsigned char *) data + octets);
908 break;
909 case 2:
911 long x = bfd_get_32 (abfd, (bfd_byte *) data + octets);
912 DOIT (x);
913 bfd_put_32 (abfd, x, (bfd_byte *) data + octets);
915 break;
916 case -2:
918 long x = bfd_get_32 (abfd, (bfd_byte *) data + octets);
919 relocation = -relocation;
920 DOIT (x);
921 bfd_put_32 (abfd, x, (bfd_byte *) data + octets);
923 break;
925 case -1:
927 long x = bfd_get_16 (abfd, (bfd_byte *) data + octets);
928 relocation = -relocation;
929 DOIT (x);
930 bfd_put_16 (abfd, x, (bfd_byte *) data + octets);
932 break;
934 case 3:
935 /* Do nothing */
936 break;
938 case 4:
939 #ifdef BFD64
941 bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + octets);
942 DOIT (x);
943 bfd_put_64 (abfd, x, (bfd_byte *) data + octets);
945 #else
946 abort ();
947 #endif
948 break;
949 default:
950 return bfd_reloc_other;
953 return flag;
957 FUNCTION
958 bfd_install_relocation
960 SYNOPSIS
961 bfd_reloc_status_type
962 bfd_install_relocation
963 (bfd *abfd,
964 arelent *reloc_entry,
965 PTR data, bfd_vma data_start,
966 asection *input_section,
967 char **error_message);
969 DESCRIPTION
970 This looks remarkably like <<bfd_perform_relocation>>, except it
971 does not expect that the section contents have been filled in.
972 I.e., it's suitable for use when creating, rather than applying
973 a relocation.
975 For now, this function should be considered reserved for the
976 assembler.
980 bfd_reloc_status_type
981 bfd_install_relocation (abfd, reloc_entry, data_start, data_start_offset,
982 input_section, error_message)
983 bfd *abfd;
984 arelent *reloc_entry;
985 PTR data_start;
986 bfd_vma data_start_offset;
987 asection *input_section;
988 char **error_message;
990 bfd_vma relocation;
991 bfd_reloc_status_type flag = bfd_reloc_ok;
992 bfd_size_type octets = reloc_entry->address * bfd_octets_per_byte (abfd);
993 bfd_vma output_base = 0;
994 reloc_howto_type *howto = reloc_entry->howto;
995 asection *reloc_target_output_section;
996 asymbol *symbol;
997 bfd_byte *data;
999 symbol = *(reloc_entry->sym_ptr_ptr);
1000 if (bfd_is_abs_section (symbol->section))
1002 reloc_entry->address += input_section->output_offset;
1003 return bfd_reloc_ok;
1006 /* If there is a function supplied to handle this relocation type,
1007 call it. It'll return `bfd_reloc_continue' if further processing
1008 can be done. */
1009 if (howto->special_function)
1011 bfd_reloc_status_type cont;
1013 /* XXX - The special_function calls haven't been fixed up to deal
1014 with creating new relocations and section contents. */
1015 cont = howto->special_function (abfd, reloc_entry, symbol,
1016 /* XXX - Non-portable! */
1017 ((bfd_byte *) data_start
1018 - data_start_offset),
1019 input_section, abfd, error_message);
1020 if (cont != bfd_reloc_continue)
1021 return cont;
1024 /* Is the address of the relocation really within the section? */
1025 if (reloc_entry->address > input_section->_cooked_size)
1026 return bfd_reloc_outofrange;
1028 /* Work out which section the relocation is targetted at and the
1029 initial relocation command value. */
1031 /* Get symbol value. (Common symbols are special.) */
1032 if (bfd_is_com_section (symbol->section))
1033 relocation = 0;
1034 else
1035 relocation = symbol->value;
1037 reloc_target_output_section = symbol->section->output_section;
1039 /* Convert input-section-relative symbol value to absolute. */
1040 if (howto->partial_inplace == false)
1041 output_base = 0;
1042 else
1043 output_base = reloc_target_output_section->vma;
1045 relocation += output_base + symbol->section->output_offset;
1047 /* Add in supplied addend. */
1048 relocation += reloc_entry->addend;
1050 /* Here the variable relocation holds the final address of the
1051 symbol we are relocating against, plus any addend. */
1053 if (howto->pc_relative == true)
1055 /* This is a PC relative relocation. We want to set RELOCATION
1056 to the distance between the address of the symbol and the
1057 location. RELOCATION is already the address of the symbol.
1059 We start by subtracting the address of the section containing
1060 the location.
1062 If pcrel_offset is set, we must further subtract the position
1063 of the location within the section. Some targets arrange for
1064 the addend to be the negative of the position of the location
1065 within the section; for example, i386-aout does this. For
1066 i386-aout, pcrel_offset is false. Some other targets do not
1067 include the position of the location; for example, m88kbcs,
1068 or ELF. For those targets, pcrel_offset is true.
1070 If we are producing relocateable output, then we must ensure
1071 that this reloc will be correctly computed when the final
1072 relocation is done. If pcrel_offset is false we want to wind
1073 up with the negative of the location within the section,
1074 which means we must adjust the existing addend by the change
1075 in the location within the section. If pcrel_offset is true
1076 we do not want to adjust the existing addend at all.
1078 FIXME: This seems logical to me, but for the case of
1079 producing relocateable output it is not what the code
1080 actually does. I don't want to change it, because it seems
1081 far too likely that something will break. */
1083 relocation -=
1084 input_section->output_section->vma + input_section->output_offset;
1086 if (howto->pcrel_offset == true && howto->partial_inplace == true)
1087 relocation -= reloc_entry->address;
1090 if (howto->partial_inplace == false)
1092 /* This is a partial relocation, and we want to apply the relocation
1093 to the reloc entry rather than the raw data. Modify the reloc
1094 inplace to reflect what we now know. */
1095 reloc_entry->addend = relocation;
1096 reloc_entry->address += input_section->output_offset;
1097 return flag;
1099 else
1101 /* This is a partial relocation, but inplace, so modify the
1102 reloc record a bit.
1104 If we've relocated with a symbol with a section, change
1105 into a ref to the section belonging to the symbol. */
1107 reloc_entry->address += input_section->output_offset;
1109 /* WTF?? */
1110 if (abfd->xvec->flavour == bfd_target_coff_flavour
1111 && strcmp (abfd->xvec->name, "coff-Intel-little") != 0
1112 && strcmp (abfd->xvec->name, "coff-Intel-big") != 0)
1114 #if 1
1115 /* For m68k-coff, the addend was being subtracted twice during
1116 relocation with -r. Removing the line below this comment
1117 fixes that problem; see PR 2953.
1119 However, Ian wrote the following, regarding removing the line below,
1120 which explains why it is still enabled: --djm
1122 If you put a patch like that into BFD you need to check all the COFF
1123 linkers. I am fairly certain that patch will break coff-i386 (e.g.,
1124 SCO); see coff_i386_reloc in coff-i386.c where I worked around the
1125 problem in a different way. There may very well be a reason that the
1126 code works as it does.
1128 Hmmm. The first obvious point is that bfd_install_relocation should
1129 not have any tests that depend upon the flavour. It's seem like
1130 entirely the wrong place for such a thing. The second obvious point
1131 is that the current code ignores the reloc addend when producing
1132 relocateable output for COFF. That's peculiar. In fact, I really
1133 have no idea what the point of the line you want to remove is.
1135 A typical COFF reloc subtracts the old value of the symbol and adds in
1136 the new value to the location in the object file (if it's a pc
1137 relative reloc it adds the difference between the symbol value and the
1138 location). When relocating we need to preserve that property.
1140 BFD handles this by setting the addend to the negative of the old
1141 value of the symbol. Unfortunately it handles common symbols in a
1142 non-standard way (it doesn't subtract the old value) but that's a
1143 different story (we can't change it without losing backward
1144 compatibility with old object files) (coff-i386 does subtract the old
1145 value, to be compatible with existing coff-i386 targets, like SCO).
1147 So everything works fine when not producing relocateable output. When
1148 we are producing relocateable output, logically we should do exactly
1149 what we do when not producing relocateable output. Therefore, your
1150 patch is correct. In fact, it should probably always just set
1151 reloc_entry->addend to 0 for all cases, since it is, in fact, going to
1152 add the value into the object file. This won't hurt the COFF code,
1153 which doesn't use the addend; I'm not sure what it will do to other
1154 formats (the thing to check for would be whether any formats both use
1155 the addend and set partial_inplace).
1157 When I wanted to make coff-i386 produce relocateable output, I ran
1158 into the problem that you are running into: I wanted to remove that
1159 line. Rather than risk it, I made the coff-i386 relocs use a special
1160 function; it's coff_i386_reloc in coff-i386.c. The function
1161 specifically adds the addend field into the object file, knowing that
1162 bfd_install_relocation is not going to. If you remove that line, then
1163 coff-i386.c will wind up adding the addend field in twice. It's
1164 trivial to fix; it just needs to be done.
1166 The problem with removing the line is just that it may break some
1167 working code. With BFD it's hard to be sure of anything. The right
1168 way to deal with this is simply to build and test at least all the
1169 supported COFF targets. It should be straightforward if time and disk
1170 space consuming. For each target:
1171 1) build the linker
1172 2) generate some executable, and link it using -r (I would
1173 probably use paranoia.o and link against newlib/libc.a, which
1174 for all the supported targets would be available in
1175 /usr/cygnus/progressive/H-host/target/lib/libc.a).
1176 3) make the change to reloc.c
1177 4) rebuild the linker
1178 5) repeat step 2
1179 6) if the resulting object files are the same, you have at least
1180 made it no worse
1181 7) if they are different you have to figure out which version is
1182 right
1184 relocation -= reloc_entry->addend;
1185 #endif
1186 reloc_entry->addend = 0;
1188 else
1190 reloc_entry->addend = relocation;
1194 /* FIXME: This overflow checking is incomplete, because the value
1195 might have overflowed before we get here. For a correct check we
1196 need to compute the value in a size larger than bitsize, but we
1197 can't reasonably do that for a reloc the same size as a host
1198 machine word.
1199 FIXME: We should also do overflow checking on the result after
1200 adding in the value contained in the object file. */
1201 if (howto->complain_on_overflow != complain_overflow_dont)
1202 flag = bfd_check_overflow (howto->complain_on_overflow,
1203 howto->bitsize,
1204 howto->rightshift,
1205 bfd_arch_bits_per_address (abfd),
1206 relocation);
1209 Either we are relocating all the way, or we don't want to apply
1210 the relocation to the reloc entry (probably because there isn't
1211 any room in the output format to describe addends to relocs)
1214 /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
1215 (OSF version 1.3, compiler version 3.11). It miscompiles the
1216 following program:
1218 struct str
1220 unsigned int i0;
1221 } s = { 0 };
1224 main ()
1226 unsigned long x;
1228 x = 0x100000000;
1229 x <<= (unsigned long) s.i0;
1230 if (x == 0)
1231 printf ("failed\n");
1232 else
1233 printf ("succeeded (%lx)\n", x);
1237 relocation >>= (bfd_vma) howto->rightshift;
1239 /* Shift everything up to where it's going to be used */
1241 relocation <<= (bfd_vma) howto->bitpos;
1243 /* Wait for the day when all have the mask in them */
1245 /* What we do:
1246 i instruction to be left alone
1247 o offset within instruction
1248 r relocation offset to apply
1249 S src mask
1250 D dst mask
1251 N ~dst mask
1252 A part 1
1253 B part 2
1254 R result
1256 Do this:
1257 (( i i i i i o o o o o from bfd_get<size>
1258 and S S S S S) to get the size offset we want
1259 + r r r r r r r r r r) to get the final value to place
1260 and D D D D D to chop to right size
1261 -----------------------
1262 = A A A A A
1263 And this:
1264 ( i i i i i o o o o o from bfd_get<size>
1265 and N N N N N ) get instruction
1266 -----------------------
1267 = B B B B B
1269 And then:
1270 ( B B B B B
1271 or A A A A A)
1272 -----------------------
1273 = R R R R R R R R R R put into bfd_put<size>
1276 #define DOIT(x) \
1277 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
1279 data = (bfd_byte *) data_start + (octets - data_start_offset);
1281 switch (howto->size)
1283 case 0:
1285 char x = bfd_get_8 (abfd, (char *) data);
1286 DOIT (x);
1287 bfd_put_8 (abfd, x, (unsigned char *) data);
1289 break;
1291 case 1:
1293 short x = bfd_get_16 (abfd, (bfd_byte *) data);
1294 DOIT (x);
1295 bfd_put_16 (abfd, x, (unsigned char *) data);
1297 break;
1298 case 2:
1300 long x = bfd_get_32 (abfd, (bfd_byte *) data);
1301 DOIT (x);
1302 bfd_put_32 (abfd, x, (bfd_byte *) data);
1304 break;
1305 case -2:
1307 long x = bfd_get_32 (abfd, (bfd_byte *) data);
1308 relocation = -relocation;
1309 DOIT (x);
1310 bfd_put_32 (abfd, x, (bfd_byte *) data);
1312 break;
1314 case 3:
1315 /* Do nothing */
1316 break;
1318 case 4:
1320 bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data);
1321 DOIT (x);
1322 bfd_put_64 (abfd, x, (bfd_byte *) data);
1324 break;
1325 default:
1326 return bfd_reloc_other;
1329 return flag;
1332 /* This relocation routine is used by some of the backend linkers.
1333 They do not construct asymbol or arelent structures, so there is no
1334 reason for them to use bfd_perform_relocation. Also,
1335 bfd_perform_relocation is so hacked up it is easier to write a new
1336 function than to try to deal with it.
1338 This routine does a final relocation. Whether it is useful for a
1339 relocateable link depends upon how the object format defines
1340 relocations.
1342 FIXME: This routine ignores any special_function in the HOWTO,
1343 since the existing special_function values have been written for
1344 bfd_perform_relocation.
1346 HOWTO is the reloc howto information.
1347 INPUT_BFD is the BFD which the reloc applies to.
1348 INPUT_SECTION is the section which the reloc applies to.
1349 CONTENTS is the contents of the section.
1350 ADDRESS is the address of the reloc within INPUT_SECTION.
1351 VALUE is the value of the symbol the reloc refers to.
1352 ADDEND is the addend of the reloc. */
1354 bfd_reloc_status_type
1355 _bfd_final_link_relocate (howto, input_bfd, input_section, contents, address,
1356 value, addend)
1357 reloc_howto_type *howto;
1358 bfd *input_bfd;
1359 asection *input_section;
1360 bfd_byte *contents;
1361 bfd_vma address;
1362 bfd_vma value;
1363 bfd_vma addend;
1365 bfd_vma relocation;
1367 /* Sanity check the address. */
1368 if (address > input_section->_raw_size)
1369 return bfd_reloc_outofrange;
1371 /* This function assumes that we are dealing with a basic relocation
1372 against a symbol. We want to compute the value of the symbol to
1373 relocate to. This is just VALUE, the value of the symbol, plus
1374 ADDEND, any addend associated with the reloc. */
1375 relocation = value + addend;
1377 /* If the relocation is PC relative, we want to set RELOCATION to
1378 the distance between the symbol (currently in RELOCATION) and the
1379 location we are relocating. Some targets (e.g., i386-aout)
1380 arrange for the contents of the section to be the negative of the
1381 offset of the location within the section; for such targets
1382 pcrel_offset is false. Other targets (e.g., m88kbcs or ELF)
1383 simply leave the contents of the section as zero; for such
1384 targets pcrel_offset is true. If pcrel_offset is false we do not
1385 need to subtract out the offset of the location within the
1386 section (which is just ADDRESS). */
1387 if (howto->pc_relative)
1389 relocation -= (input_section->output_section->vma
1390 + input_section->output_offset);
1391 if (howto->pcrel_offset)
1392 relocation -= address;
1395 return _bfd_relocate_contents (howto, input_bfd, relocation,
1396 contents + address);
1399 /* Relocate a given location using a given value and howto. */
1401 bfd_reloc_status_type
1402 _bfd_relocate_contents (howto, input_bfd, relocation, location)
1403 reloc_howto_type *howto;
1404 bfd *input_bfd;
1405 bfd_vma relocation;
1406 bfd_byte *location;
1408 int size;
1409 bfd_vma x = 0;
1410 bfd_reloc_status_type flag;
1411 unsigned int rightshift = howto->rightshift;
1412 unsigned int bitpos = howto->bitpos;
1414 /* If the size is negative, negate RELOCATION. This isn't very
1415 general. */
1416 if (howto->size < 0)
1417 relocation = -relocation;
1419 /* Get the value we are going to relocate. */
1420 size = bfd_get_reloc_size (howto);
1421 switch (size)
1423 default:
1424 case 0:
1425 abort ();
1426 case 1:
1427 x = bfd_get_8 (input_bfd, location);
1428 break;
1429 case 2:
1430 x = bfd_get_16 (input_bfd, location);
1431 break;
1432 case 4:
1433 x = bfd_get_32 (input_bfd, location);
1434 break;
1435 case 8:
1436 #ifdef BFD64
1437 x = bfd_get_64 (input_bfd, location);
1438 #else
1439 abort ();
1440 #endif
1441 break;
1444 /* Check for overflow. FIXME: We may drop bits during the addition
1445 which we don't check for. We must either check at every single
1446 operation, which would be tedious, or we must do the computations
1447 in a type larger than bfd_vma, which would be inefficient. */
1448 flag = bfd_reloc_ok;
1449 if (howto->complain_on_overflow != complain_overflow_dont)
1451 bfd_vma addrmask, fieldmask, signmask, ss;
1452 bfd_vma a, b, sum;
1454 /* Get the values to be added together. For signed and unsigned
1455 relocations, we assume that all values should be truncated to
1456 the size of an address. For bitfields, all the bits matter.
1457 See also bfd_check_overflow. */
1458 fieldmask = N_ONES (howto->bitsize);
1459 addrmask = N_ONES (bfd_arch_bits_per_address (input_bfd)) | fieldmask;
1460 a = relocation;
1461 b = x & howto->src_mask;
1463 switch (howto->complain_on_overflow)
1465 case complain_overflow_signed:
1466 a = (a & addrmask) >> rightshift;
1468 /* If any sign bits are set, all sign bits must be set.
1469 That is, A must be a valid negative address after
1470 shifting. */
1471 signmask = ~ (fieldmask >> 1);
1472 ss = a & signmask;
1473 if (ss != 0 && ss != ((addrmask >> rightshift) & signmask))
1474 flag = bfd_reloc_overflow;
1476 /* We only need this next bit of code if the sign bit of B
1477 is below the sign bit of A. This would only happen if
1478 SRC_MASK had fewer bits than BITSIZE. Note that if
1479 SRC_MASK has more bits than BITSIZE, we can get into
1480 trouble; we would need to verify that B is in range, as
1481 we do for A above. */
1482 signmask = ((~ howto->src_mask) >> 1) & howto->src_mask;
1484 /* Set all the bits above the sign bit. */
1485 b = (b ^ signmask) - signmask;
1487 b = (b & addrmask) >> bitpos;
1489 /* Now we can do the addition. */
1490 sum = a + b;
1492 /* See if the result has the correct sign. Bits above the
1493 sign bit are junk now; ignore them. If the sum is
1494 positive, make sure we did not have all negative inputs;
1495 if the sum is negative, make sure we did not have all
1496 positive inputs. The test below looks only at the sign
1497 bits, and it really just
1498 SIGN (A) == SIGN (B) && SIGN (A) != SIGN (SUM)
1500 signmask = (fieldmask >> 1) + 1;
1501 if (((~ (a ^ b)) & (a ^ sum)) & signmask)
1502 flag = bfd_reloc_overflow;
1504 break;
1506 case complain_overflow_unsigned:
1507 /* Checking for an unsigned overflow is relatively easy:
1508 trim the addresses and add, and trim the result as well.
1509 Overflow is normally indicated when the result does not
1510 fit in the field. However, we also need to consider the
1511 case when, e.g., fieldmask is 0x7fffffff or smaller, an
1512 input is 0x80000000, and bfd_vma is only 32 bits; then we
1513 will get sum == 0, but there is an overflow, since the
1514 inputs did not fit in the field. Instead of doing a
1515 separate test, we can check for this by or-ing in the
1516 operands when testing for the sum overflowing its final
1517 field. */
1518 a = (a & addrmask) >> rightshift;
1519 b = (b & addrmask) >> bitpos;
1520 sum = (a + b) & addrmask;
1521 if ((a | b | sum) & ~ fieldmask)
1522 flag = bfd_reloc_overflow;
1524 break;
1526 case complain_overflow_bitfield:
1527 /* Much like the signed check, but for a field one bit
1528 wider, and no trimming inputs with addrmask. We allow a
1529 bitfield to represent numbers in the range -2**n to
1530 2**n-1, where n is the number of bits in the field.
1531 Note that when bfd_vma is 32 bits, a 32-bit reloc can't
1532 overflow, which is exactly what we want. */
1533 a >>= rightshift;
1535 signmask = ~ fieldmask;
1536 ss = a & signmask;
1537 if (ss != 0 && ss != (((bfd_vma) -1 >> rightshift) & signmask))
1538 flag = bfd_reloc_overflow;
1540 signmask = ((~ howto->src_mask) >> 1) & howto->src_mask;
1541 b = (b ^ signmask) - signmask;
1543 b >>= bitpos;
1545 sum = a + b;
1547 /* We mask with addrmask here to explicitly allow an address
1548 wrap-around. The Linux kernel relies on it, and it is
1549 the only way to write assembler code which can run when
1550 loaded at a location 0x80000000 away from the location at
1551 which it is linked. */
1552 signmask = fieldmask + 1;
1553 if (((~ (a ^ b)) & (a ^ sum)) & signmask & addrmask)
1554 flag = bfd_reloc_overflow;
1556 break;
1558 default:
1559 abort ();
1563 /* Put RELOCATION in the right bits. */
1564 relocation >>= (bfd_vma) rightshift;
1565 relocation <<= (bfd_vma) bitpos;
1567 /* Add RELOCATION to the right bits of X. */
1568 x = ((x & ~howto->dst_mask)
1569 | (((x & howto->src_mask) + relocation) & howto->dst_mask));
1571 /* Put the relocated value back in the object file. */
1572 switch (size)
1574 default:
1575 case 0:
1576 abort ();
1577 case 1:
1578 bfd_put_8 (input_bfd, x, location);
1579 break;
1580 case 2:
1581 bfd_put_16 (input_bfd, x, location);
1582 break;
1583 case 4:
1584 bfd_put_32 (input_bfd, x, location);
1585 break;
1586 case 8:
1587 #ifdef BFD64
1588 bfd_put_64 (input_bfd, x, location);
1589 #else
1590 abort ();
1591 #endif
1592 break;
1595 return flag;
1599 DOCDD
1600 INODE
1601 howto manager, , typedef arelent, Relocations
1603 SECTION
1604 The howto manager
1606 When an application wants to create a relocation, but doesn't
1607 know what the target machine might call it, it can find out by
1608 using this bit of code.
1613 TYPEDEF
1614 bfd_reloc_code_type
1616 DESCRIPTION
1617 The insides of a reloc code. The idea is that, eventually, there
1618 will be one enumerator for every type of relocation we ever do.
1619 Pass one of these values to <<bfd_reloc_type_lookup>>, and it'll
1620 return a howto pointer.
1622 This does mean that the application must determine the correct
1623 enumerator value; you can't get a howto pointer from a random set
1624 of attributes.
1626 SENUM
1627 bfd_reloc_code_real
1629 ENUM
1630 BFD_RELOC_64
1631 ENUMX
1632 BFD_RELOC_32
1633 ENUMX
1634 BFD_RELOC_26
1635 ENUMX
1636 BFD_RELOC_24
1637 ENUMX
1638 BFD_RELOC_16
1639 ENUMX
1640 BFD_RELOC_14
1641 ENUMX
1642 BFD_RELOC_8
1643 ENUMDOC
1644 Basic absolute relocations of N bits.
1646 ENUM
1647 BFD_RELOC_64_PCREL
1648 ENUMX
1649 BFD_RELOC_32_PCREL
1650 ENUMX
1651 BFD_RELOC_24_PCREL
1652 ENUMX
1653 BFD_RELOC_16_PCREL
1654 ENUMX
1655 BFD_RELOC_12_PCREL
1656 ENUMX
1657 BFD_RELOC_8_PCREL
1658 ENUMDOC
1659 PC-relative relocations. Sometimes these are relative to the address
1660 of the relocation itself; sometimes they are relative to the start of
1661 the section containing the relocation. It depends on the specific target.
1663 The 24-bit relocation is used in some Intel 960 configurations.
1665 ENUM
1666 BFD_RELOC_32_GOT_PCREL
1667 ENUMX
1668 BFD_RELOC_16_GOT_PCREL
1669 ENUMX
1670 BFD_RELOC_8_GOT_PCREL
1671 ENUMX
1672 BFD_RELOC_32_GOTOFF
1673 ENUMX
1674 BFD_RELOC_16_GOTOFF
1675 ENUMX
1676 BFD_RELOC_LO16_GOTOFF
1677 ENUMX
1678 BFD_RELOC_HI16_GOTOFF
1679 ENUMX
1680 BFD_RELOC_HI16_S_GOTOFF
1681 ENUMX
1682 BFD_RELOC_8_GOTOFF
1683 ENUMX
1684 BFD_RELOC_32_PLT_PCREL
1685 ENUMX
1686 BFD_RELOC_24_PLT_PCREL
1687 ENUMX
1688 BFD_RELOC_16_PLT_PCREL
1689 ENUMX
1690 BFD_RELOC_8_PLT_PCREL
1691 ENUMX
1692 BFD_RELOC_32_PLTOFF
1693 ENUMX
1694 BFD_RELOC_16_PLTOFF
1695 ENUMX
1696 BFD_RELOC_LO16_PLTOFF
1697 ENUMX
1698 BFD_RELOC_HI16_PLTOFF
1699 ENUMX
1700 BFD_RELOC_HI16_S_PLTOFF
1701 ENUMX
1702 BFD_RELOC_8_PLTOFF
1703 ENUMDOC
1704 For ELF.
1706 ENUM
1707 BFD_RELOC_68K_GLOB_DAT
1708 ENUMX
1709 BFD_RELOC_68K_JMP_SLOT
1710 ENUMX
1711 BFD_RELOC_68K_RELATIVE
1712 ENUMDOC
1713 Relocations used by 68K ELF.
1715 ENUM
1716 BFD_RELOC_32_BASEREL
1717 ENUMX
1718 BFD_RELOC_16_BASEREL
1719 ENUMX
1720 BFD_RELOC_LO16_BASEREL
1721 ENUMX
1722 BFD_RELOC_HI16_BASEREL
1723 ENUMX
1724 BFD_RELOC_HI16_S_BASEREL
1725 ENUMX
1726 BFD_RELOC_8_BASEREL
1727 ENUMX
1728 BFD_RELOC_RVA
1729 ENUMDOC
1730 Linkage-table relative.
1732 ENUM
1733 BFD_RELOC_8_FFnn
1734 ENUMDOC
1735 Absolute 8-bit relocation, but used to form an address like 0xFFnn.
1737 ENUM
1738 BFD_RELOC_32_PCREL_S2
1739 ENUMX
1740 BFD_RELOC_16_PCREL_S2
1741 ENUMX
1742 BFD_RELOC_23_PCREL_S2
1743 ENUMDOC
1744 These PC-relative relocations are stored as word displacements --
1745 i.e., byte displacements shifted right two bits. The 30-bit word
1746 displacement (<<32_PCREL_S2>> -- 32 bits, shifted 2) is used on the
1747 SPARC. (SPARC tools generally refer to this as <<WDISP30>>.) The
1748 signed 16-bit displacement is used on the MIPS, and the 23-bit
1749 displacement is used on the Alpha.
1751 ENUM
1752 BFD_RELOC_HI22
1753 ENUMX
1754 BFD_RELOC_LO10
1755 ENUMDOC
1756 High 22 bits and low 10 bits of 32-bit value, placed into lower bits of
1757 the target word. These are used on the SPARC.
1759 ENUM
1760 BFD_RELOC_GPREL16
1761 ENUMX
1762 BFD_RELOC_GPREL32
1763 ENUMDOC
1764 For systems that allocate a Global Pointer register, these are
1765 displacements off that register. These relocation types are
1766 handled specially, because the value the register will have is
1767 decided relatively late.
1769 ENUM
1770 BFD_RELOC_I960_CALLJ
1771 ENUMDOC
1772 Reloc types used for i960/b.out.
1774 ENUM
1775 BFD_RELOC_NONE
1776 ENUMX
1777 BFD_RELOC_SPARC_WDISP22
1778 ENUMX
1779 BFD_RELOC_SPARC22
1780 ENUMX
1781 BFD_RELOC_SPARC13
1782 ENUMX
1783 BFD_RELOC_SPARC_GOT10
1784 ENUMX
1785 BFD_RELOC_SPARC_GOT13
1786 ENUMX
1787 BFD_RELOC_SPARC_GOT22
1788 ENUMX
1789 BFD_RELOC_SPARC_PC10
1790 ENUMX
1791 BFD_RELOC_SPARC_PC22
1792 ENUMX
1793 BFD_RELOC_SPARC_WPLT30
1794 ENUMX
1795 BFD_RELOC_SPARC_COPY
1796 ENUMX
1797 BFD_RELOC_SPARC_GLOB_DAT
1798 ENUMX
1799 BFD_RELOC_SPARC_JMP_SLOT
1800 ENUMX
1801 BFD_RELOC_SPARC_RELATIVE
1802 ENUMX
1803 BFD_RELOC_SPARC_UA32
1804 ENUMDOC
1805 SPARC ELF relocations. There is probably some overlap with other
1806 relocation types already defined.
1808 ENUM
1809 BFD_RELOC_SPARC_BASE13
1810 ENUMX
1811 BFD_RELOC_SPARC_BASE22
1812 ENUMDOC
1813 I think these are specific to SPARC a.out (e.g., Sun 4).
1815 ENUMEQ
1816 BFD_RELOC_SPARC_64
1817 BFD_RELOC_64
1818 ENUMX
1819 BFD_RELOC_SPARC_10
1820 ENUMX
1821 BFD_RELOC_SPARC_11
1822 ENUMX
1823 BFD_RELOC_SPARC_OLO10
1824 ENUMX
1825 BFD_RELOC_SPARC_HH22
1826 ENUMX
1827 BFD_RELOC_SPARC_HM10
1828 ENUMX
1829 BFD_RELOC_SPARC_LM22
1830 ENUMX
1831 BFD_RELOC_SPARC_PC_HH22
1832 ENUMX
1833 BFD_RELOC_SPARC_PC_HM10
1834 ENUMX
1835 BFD_RELOC_SPARC_PC_LM22
1836 ENUMX
1837 BFD_RELOC_SPARC_WDISP16
1838 ENUMX
1839 BFD_RELOC_SPARC_WDISP19
1840 ENUMX
1841 BFD_RELOC_SPARC_7
1842 ENUMX
1843 BFD_RELOC_SPARC_6
1844 ENUMX
1845 BFD_RELOC_SPARC_5
1846 ENUMEQX
1847 BFD_RELOC_SPARC_DISP64
1848 BFD_RELOC_64_PCREL
1849 ENUMX
1850 BFD_RELOC_SPARC_PLT64
1851 ENUMX
1852 BFD_RELOC_SPARC_HIX22
1853 ENUMX
1854 BFD_RELOC_SPARC_LOX10
1855 ENUMX
1856 BFD_RELOC_SPARC_H44
1857 ENUMX
1858 BFD_RELOC_SPARC_M44
1859 ENUMX
1860 BFD_RELOC_SPARC_L44
1861 ENUMX
1862 BFD_RELOC_SPARC_REGISTER
1863 ENUMDOC
1864 SPARC64 relocations
1866 ENUM
1867 BFD_RELOC_SPARC_REV32
1868 ENUMDOC
1869 SPARC little endian relocation
1871 ENUM
1872 BFD_RELOC_ALPHA_GPDISP_HI16
1873 ENUMDOC
1874 Alpha ECOFF and ELF relocations. Some of these treat the symbol or
1875 "addend" in some special way.
1876 For GPDISP_HI16 ("gpdisp") relocations, the symbol is ignored when
1877 writing; when reading, it will be the absolute section symbol. The
1878 addend is the displacement in bytes of the "lda" instruction from
1879 the "ldah" instruction (which is at the address of this reloc).
1880 ENUM
1881 BFD_RELOC_ALPHA_GPDISP_LO16
1882 ENUMDOC
1883 For GPDISP_LO16 ("ignore") relocations, the symbol is handled as
1884 with GPDISP_HI16 relocs. The addend is ignored when writing the
1885 relocations out, and is filled in with the file's GP value on
1886 reading, for convenience.
1888 ENUM
1889 BFD_RELOC_ALPHA_GPDISP
1890 ENUMDOC
1891 The ELF GPDISP relocation is exactly the same as the GPDISP_HI16
1892 relocation except that there is no accompanying GPDISP_LO16
1893 relocation.
1895 ENUM
1896 BFD_RELOC_ALPHA_LITERAL
1897 ENUMX
1898 BFD_RELOC_ALPHA_ELF_LITERAL
1899 ENUMX
1900 BFD_RELOC_ALPHA_LITUSE
1901 ENUMDOC
1902 The Alpha LITERAL/LITUSE relocs are produced by a symbol reference;
1903 the assembler turns it into a LDQ instruction to load the address of
1904 the symbol, and then fills in a register in the real instruction.
1906 The LITERAL reloc, at the LDQ instruction, refers to the .lita
1907 section symbol. The addend is ignored when writing, but is filled
1908 in with the file's GP value on reading, for convenience, as with the
1909 GPDISP_LO16 reloc.
1911 The ELF_LITERAL reloc is somewhere between 16_GOTOFF and GPDISP_LO16.
1912 It should refer to the symbol to be referenced, as with 16_GOTOFF,
1913 but it generates output not based on the position within the .got
1914 section, but relative to the GP value chosen for the file during the
1915 final link stage.
1917 The LITUSE reloc, on the instruction using the loaded address, gives
1918 information to the linker that it might be able to use to optimize
1919 away some literal section references. The symbol is ignored (read
1920 as the absolute section symbol), and the "addend" indicates the type
1921 of instruction using the register:
1922 1 - "memory" fmt insn
1923 2 - byte-manipulation (byte offset reg)
1924 3 - jsr (target of branch)
1926 The GNU linker currently doesn't do any of this optimizing.
1928 ENUM
1929 BFD_RELOC_ALPHA_USER_LITERAL
1930 ENUMX
1931 BFD_RELOC_ALPHA_USER_LITUSE_BASE
1932 ENUMX
1933 BFD_RELOC_ALPHA_USER_LITUSE_BYTOFF
1934 ENUMX
1935 BFD_RELOC_ALPHA_USER_LITUSE_JSR
1936 ENUMX
1937 BFD_RELOC_ALPHA_USER_GPDISP
1938 ENUMX
1939 BFD_RELOC_ALPHA_USER_GPRELHIGH
1940 ENUMX
1941 BFD_RELOC_ALPHA_USER_GPRELLOW
1942 ENUMDOC
1943 The BFD_RELOC_ALPHA_USER_* relocations are used by the assembler to
1944 process the explicit !<reloc>!sequence relocations, and are mapped
1945 into the normal relocations at the end of processing.
1947 ENUM
1948 BFD_RELOC_ALPHA_HINT
1949 ENUMDOC
1950 The HINT relocation indicates a value that should be filled into the
1951 "hint" field of a jmp/jsr/ret instruction, for possible branch-
1952 prediction logic which may be provided on some processors.
1954 ENUM
1955 BFD_RELOC_ALPHA_LINKAGE
1956 ENUMDOC
1957 The LINKAGE relocation outputs a linkage pair in the object file,
1958 which is filled by the linker.
1960 ENUM
1961 BFD_RELOC_ALPHA_CODEADDR
1962 ENUMDOC
1963 The CODEADDR relocation outputs a STO_CA in the object file,
1964 which is filled by the linker.
1966 ENUM
1967 BFD_RELOC_MIPS_JMP
1968 ENUMDOC
1969 Bits 27..2 of the relocation address shifted right 2 bits;
1970 simple reloc otherwise.
1972 ENUM
1973 BFD_RELOC_MIPS16_JMP
1974 ENUMDOC
1975 The MIPS16 jump instruction.
1977 ENUM
1978 BFD_RELOC_MIPS16_GPREL
1979 ENUMDOC
1980 MIPS16 GP relative reloc.
1982 ENUM
1983 BFD_RELOC_HI16
1984 ENUMDOC
1985 High 16 bits of 32-bit value; simple reloc.
1986 ENUM
1987 BFD_RELOC_HI16_S
1988 ENUMDOC
1989 High 16 bits of 32-bit value but the low 16 bits will be sign
1990 extended and added to form the final result. If the low 16
1991 bits form a negative number, we need to add one to the high value
1992 to compensate for the borrow when the low bits are added.
1993 ENUM
1994 BFD_RELOC_LO16
1995 ENUMDOC
1996 Low 16 bits.
1997 ENUM
1998 BFD_RELOC_PCREL_HI16_S
1999 ENUMDOC
2000 Like BFD_RELOC_HI16_S, but PC relative.
2001 ENUM
2002 BFD_RELOC_PCREL_LO16
2003 ENUMDOC
2004 Like BFD_RELOC_LO16, but PC relative.
2006 ENUMEQ
2007 BFD_RELOC_MIPS_GPREL
2008 BFD_RELOC_GPREL16
2009 ENUMDOC
2010 Relocation relative to the global pointer.
2012 ENUM
2013 BFD_RELOC_MIPS_LITERAL
2014 ENUMDOC
2015 Relocation against a MIPS literal section.
2017 ENUM
2018 BFD_RELOC_MIPS_GOT16
2019 ENUMX
2020 BFD_RELOC_MIPS_CALL16
2021 ENUMEQX
2022 BFD_RELOC_MIPS_GPREL32
2023 BFD_RELOC_GPREL32
2024 ENUMX
2025 BFD_RELOC_MIPS_GOT_HI16
2026 ENUMX
2027 BFD_RELOC_MIPS_GOT_LO16
2028 ENUMX
2029 BFD_RELOC_MIPS_CALL_HI16
2030 ENUMX
2031 BFD_RELOC_MIPS_CALL_LO16
2032 ENUMX
2033 BFD_RELOC_MIPS_SUB
2034 ENUMX
2035 BFD_RELOC_MIPS_GOT_PAGE
2036 ENUMX
2037 BFD_RELOC_MIPS_GOT_OFST
2038 ENUMX
2039 BFD_RELOC_MIPS_GOT_DISP
2040 COMMENT
2041 ENUMDOC
2042 MIPS ELF relocations.
2044 COMMENT
2046 ENUM
2047 BFD_RELOC_386_GOT32
2048 ENUMX
2049 BFD_RELOC_386_PLT32
2050 ENUMX
2051 BFD_RELOC_386_COPY
2052 ENUMX
2053 BFD_RELOC_386_GLOB_DAT
2054 ENUMX
2055 BFD_RELOC_386_JUMP_SLOT
2056 ENUMX
2057 BFD_RELOC_386_RELATIVE
2058 ENUMX
2059 BFD_RELOC_386_GOTOFF
2060 ENUMX
2061 BFD_RELOC_386_GOTPC
2062 ENUMDOC
2063 i386/elf relocations
2065 ENUM
2066 BFD_RELOC_X86_64_GOT32
2067 ENUMX
2068 BFD_RELOC_X86_64_PLT32
2069 ENUMX
2070 BFD_RELOC_X86_64_COPY
2071 ENUMX
2072 BFD_RELOC_X86_64_GLOB_DAT
2073 ENUMX
2074 BFD_RELOC_X86_64_JUMP_SLOT
2075 ENUMX
2076 BFD_RELOC_X86_64_RELATIVE
2077 ENUMX
2078 BFD_RELOC_X86_64_GOTPCREL
2079 ENUMX
2080 BFD_RELOC_X86_64_32S
2081 ENUMDOC
2082 x86-64/elf relocations
2084 ENUM
2085 BFD_RELOC_NS32K_IMM_8
2086 ENUMX
2087 BFD_RELOC_NS32K_IMM_16
2088 ENUMX
2089 BFD_RELOC_NS32K_IMM_32
2090 ENUMX
2091 BFD_RELOC_NS32K_IMM_8_PCREL
2092 ENUMX
2093 BFD_RELOC_NS32K_IMM_16_PCREL
2094 ENUMX
2095 BFD_RELOC_NS32K_IMM_32_PCREL
2096 ENUMX
2097 BFD_RELOC_NS32K_DISP_8
2098 ENUMX
2099 BFD_RELOC_NS32K_DISP_16
2100 ENUMX
2101 BFD_RELOC_NS32K_DISP_32
2102 ENUMX
2103 BFD_RELOC_NS32K_DISP_8_PCREL
2104 ENUMX
2105 BFD_RELOC_NS32K_DISP_16_PCREL
2106 ENUMX
2107 BFD_RELOC_NS32K_DISP_32_PCREL
2108 ENUMDOC
2109 ns32k relocations
2111 ENUM
2112 BFD_RELOC_PDP11_DISP_8_PCREL
2113 ENUMX
2114 BFD_RELOC_PDP11_DISP_6_PCREL
2115 ENUMDOC
2116 PDP11 relocations
2118 ENUM
2119 BFD_RELOC_PJ_CODE_HI16
2120 ENUMX
2121 BFD_RELOC_PJ_CODE_LO16
2122 ENUMX
2123 BFD_RELOC_PJ_CODE_DIR16
2124 ENUMX
2125 BFD_RELOC_PJ_CODE_DIR32
2126 ENUMX
2127 BFD_RELOC_PJ_CODE_REL16
2128 ENUMX
2129 BFD_RELOC_PJ_CODE_REL32
2130 ENUMDOC
2131 Picojava relocs. Not all of these appear in object files.
2133 ENUM
2134 BFD_RELOC_PPC_B26
2135 ENUMX
2136 BFD_RELOC_PPC_BA26
2137 ENUMX
2138 BFD_RELOC_PPC_TOC16
2139 ENUMX
2140 BFD_RELOC_PPC_B16
2141 ENUMX
2142 BFD_RELOC_PPC_B16_BRTAKEN
2143 ENUMX
2144 BFD_RELOC_PPC_B16_BRNTAKEN
2145 ENUMX
2146 BFD_RELOC_PPC_BA16
2147 ENUMX
2148 BFD_RELOC_PPC_BA16_BRTAKEN
2149 ENUMX
2150 BFD_RELOC_PPC_BA16_BRNTAKEN
2151 ENUMX
2152 BFD_RELOC_PPC_COPY
2153 ENUMX
2154 BFD_RELOC_PPC_GLOB_DAT
2155 ENUMX
2156 BFD_RELOC_PPC_JMP_SLOT
2157 ENUMX
2158 BFD_RELOC_PPC_RELATIVE
2159 ENUMX
2160 BFD_RELOC_PPC_LOCAL24PC
2161 ENUMX
2162 BFD_RELOC_PPC_EMB_NADDR32
2163 ENUMX
2164 BFD_RELOC_PPC_EMB_NADDR16
2165 ENUMX
2166 BFD_RELOC_PPC_EMB_NADDR16_LO
2167 ENUMX
2168 BFD_RELOC_PPC_EMB_NADDR16_HI
2169 ENUMX
2170 BFD_RELOC_PPC_EMB_NADDR16_HA
2171 ENUMX
2172 BFD_RELOC_PPC_EMB_SDAI16
2173 ENUMX
2174 BFD_RELOC_PPC_EMB_SDA2I16
2175 ENUMX
2176 BFD_RELOC_PPC_EMB_SDA2REL
2177 ENUMX
2178 BFD_RELOC_PPC_EMB_SDA21
2179 ENUMX
2180 BFD_RELOC_PPC_EMB_MRKREF
2181 ENUMX
2182 BFD_RELOC_PPC_EMB_RELSEC16
2183 ENUMX
2184 BFD_RELOC_PPC_EMB_RELST_LO
2185 ENUMX
2186 BFD_RELOC_PPC_EMB_RELST_HI
2187 ENUMX
2188 BFD_RELOC_PPC_EMB_RELST_HA
2189 ENUMX
2190 BFD_RELOC_PPC_EMB_BIT_FLD
2191 ENUMX
2192 BFD_RELOC_PPC_EMB_RELSDA
2193 ENUMDOC
2194 Power(rs6000) and PowerPC relocations.
2196 ENUM
2197 BFD_RELOC_I370_D12
2198 ENUMDOC
2199 IBM 370/390 relocations
2201 ENUM
2202 BFD_RELOC_CTOR
2203 ENUMDOC
2204 The type of reloc used to build a contructor table - at the moment
2205 probably a 32 bit wide absolute relocation, but the target can choose.
2206 It generally does map to one of the other relocation types.
2208 ENUM
2209 BFD_RELOC_ARM_PCREL_BRANCH
2210 ENUMDOC
2211 ARM 26 bit pc-relative branch. The lowest two bits must be zero and are
2212 not stored in the instruction.
2213 ENUM
2214 BFD_RELOC_ARM_PCREL_BLX
2215 ENUMDOC
2216 ARM 26 bit pc-relative branch. The lowest bit must be zero and is
2217 not stored in the instruction. The 2nd lowest bit comes from a 1 bit
2218 field in the instruction.
2219 ENUM
2220 BFD_RELOC_THUMB_PCREL_BLX
2221 ENUMDOC
2222 Thumb 22 bit pc-relative branch. The lowest bit must be zero and is
2223 not stored in the instruction. The 2nd lowest bit comes from a 1 bit
2224 field in the instruction.
2225 ENUM
2226 BFD_RELOC_ARM_IMMEDIATE
2227 ENUMX
2228 BFD_RELOC_ARM_ADRL_IMMEDIATE
2229 ENUMX
2230 BFD_RELOC_ARM_OFFSET_IMM
2231 ENUMX
2232 BFD_RELOC_ARM_SHIFT_IMM
2233 ENUMX
2234 BFD_RELOC_ARM_SWI
2235 ENUMX
2236 BFD_RELOC_ARM_MULTI
2237 ENUMX
2238 BFD_RELOC_ARM_CP_OFF_IMM
2239 ENUMX
2240 BFD_RELOC_ARM_ADR_IMM
2241 ENUMX
2242 BFD_RELOC_ARM_LDR_IMM
2243 ENUMX
2244 BFD_RELOC_ARM_LITERAL
2245 ENUMX
2246 BFD_RELOC_ARM_IN_POOL
2247 ENUMX
2248 BFD_RELOC_ARM_OFFSET_IMM8
2249 ENUMX
2250 BFD_RELOC_ARM_HWLITERAL
2251 ENUMX
2252 BFD_RELOC_ARM_THUMB_ADD
2253 ENUMX
2254 BFD_RELOC_ARM_THUMB_IMM
2255 ENUMX
2256 BFD_RELOC_ARM_THUMB_SHIFT
2257 ENUMX
2258 BFD_RELOC_ARM_THUMB_OFFSET
2259 ENUMX
2260 BFD_RELOC_ARM_GOT12
2261 ENUMX
2262 BFD_RELOC_ARM_GOT32
2263 ENUMX
2264 BFD_RELOC_ARM_JUMP_SLOT
2265 ENUMX
2266 BFD_RELOC_ARM_COPY
2267 ENUMX
2268 BFD_RELOC_ARM_GLOB_DAT
2269 ENUMX
2270 BFD_RELOC_ARM_PLT32
2271 ENUMX
2272 BFD_RELOC_ARM_RELATIVE
2273 ENUMX
2274 BFD_RELOC_ARM_GOTOFF
2275 ENUMX
2276 BFD_RELOC_ARM_GOTPC
2277 ENUMDOC
2278 These relocs are only used within the ARM assembler. They are not
2279 (at present) written to any object files.
2281 ENUM
2282 BFD_RELOC_SH_PCDISP8BY2
2283 ENUMX
2284 BFD_RELOC_SH_PCDISP12BY2
2285 ENUMX
2286 BFD_RELOC_SH_IMM4
2287 ENUMX
2288 BFD_RELOC_SH_IMM4BY2
2289 ENUMX
2290 BFD_RELOC_SH_IMM4BY4
2291 ENUMX
2292 BFD_RELOC_SH_IMM8
2293 ENUMX
2294 BFD_RELOC_SH_IMM8BY2
2295 ENUMX
2296 BFD_RELOC_SH_IMM8BY4
2297 ENUMX
2298 BFD_RELOC_SH_PCRELIMM8BY2
2299 ENUMX
2300 BFD_RELOC_SH_PCRELIMM8BY4
2301 ENUMX
2302 BFD_RELOC_SH_SWITCH16
2303 ENUMX
2304 BFD_RELOC_SH_SWITCH32
2305 ENUMX
2306 BFD_RELOC_SH_USES
2307 ENUMX
2308 BFD_RELOC_SH_COUNT
2309 ENUMX
2310 BFD_RELOC_SH_ALIGN
2311 ENUMX
2312 BFD_RELOC_SH_CODE
2313 ENUMX
2314 BFD_RELOC_SH_DATA
2315 ENUMX
2316 BFD_RELOC_SH_LABEL
2317 ENUMX
2318 BFD_RELOC_SH_LOOP_START
2319 ENUMX
2320 BFD_RELOC_SH_LOOP_END
2321 ENUMX
2322 BFD_RELOC_SH_COPY
2323 ENUMX
2324 BFD_RELOC_SH_GLOB_DAT
2325 ENUMX
2326 BFD_RELOC_SH_JMP_SLOT
2327 ENUMX
2328 BFD_RELOC_SH_RELATIVE
2329 ENUMX
2330 BFD_RELOC_SH_GOTPC
2331 ENUMDOC
2332 Hitachi SH relocs. Not all of these appear in object files.
2334 ENUM
2335 BFD_RELOC_THUMB_PCREL_BRANCH9
2336 ENUMX
2337 BFD_RELOC_THUMB_PCREL_BRANCH12
2338 ENUMX
2339 BFD_RELOC_THUMB_PCREL_BRANCH23
2340 ENUMDOC
2341 Thumb 23-, 12- and 9-bit pc-relative branches. The lowest bit must
2342 be zero and is not stored in the instruction.
2344 ENUM
2345 BFD_RELOC_ARC_B22_PCREL
2346 ENUMDOC
2347 ARC Cores relocs.
2348 ARC 22 bit pc-relative branch. The lowest two bits must be zero and are
2349 not stored in the instruction. The high 20 bits are installed in bits 26
2350 through 7 of the instruction.
2351 ENUM
2352 BFD_RELOC_ARC_B26
2353 ENUMDOC
2354 ARC 26 bit absolute branch. The lowest two bits must be zero and are not
2355 stored in the instruction. The high 24 bits are installed in bits 23
2356 through 0.
2358 ENUM
2359 BFD_RELOC_D10V_10_PCREL_R
2360 ENUMDOC
2361 Mitsubishi D10V relocs.
2362 This is a 10-bit reloc with the right 2 bits
2363 assumed to be 0.
2364 ENUM
2365 BFD_RELOC_D10V_10_PCREL_L
2366 ENUMDOC
2367 Mitsubishi D10V relocs.
2368 This is a 10-bit reloc with the right 2 bits
2369 assumed to be 0. This is the same as the previous reloc
2370 except it is in the left container, i.e.,
2371 shifted left 15 bits.
2372 ENUM
2373 BFD_RELOC_D10V_18
2374 ENUMDOC
2375 This is an 18-bit reloc with the right 2 bits
2376 assumed to be 0.
2377 ENUM
2378 BFD_RELOC_D10V_18_PCREL
2379 ENUMDOC
2380 This is an 18-bit reloc with the right 2 bits
2381 assumed to be 0.
2383 ENUM
2384 BFD_RELOC_D30V_6
2385 ENUMDOC
2386 Mitsubishi D30V relocs.
2387 This is a 6-bit absolute reloc.
2388 ENUM
2389 BFD_RELOC_D30V_9_PCREL
2390 ENUMDOC
2391 This is a 6-bit pc-relative reloc with
2392 the right 3 bits assumed to be 0.
2393 ENUM
2394 BFD_RELOC_D30V_9_PCREL_R
2395 ENUMDOC
2396 This is a 6-bit pc-relative reloc with
2397 the right 3 bits assumed to be 0. Same
2398 as the previous reloc but on the right side
2399 of the container.
2400 ENUM
2401 BFD_RELOC_D30V_15
2402 ENUMDOC
2403 This is a 12-bit absolute reloc with the
2404 right 3 bitsassumed to be 0.
2405 ENUM
2406 BFD_RELOC_D30V_15_PCREL
2407 ENUMDOC
2408 This is a 12-bit pc-relative reloc with
2409 the right 3 bits assumed to be 0.
2410 ENUM
2411 BFD_RELOC_D30V_15_PCREL_R
2412 ENUMDOC
2413 This is a 12-bit pc-relative reloc with
2414 the right 3 bits assumed to be 0. Same
2415 as the previous reloc but on the right side
2416 of the container.
2417 ENUM
2418 BFD_RELOC_D30V_21
2419 ENUMDOC
2420 This is an 18-bit absolute reloc with
2421 the right 3 bits assumed to be 0.
2422 ENUM
2423 BFD_RELOC_D30V_21_PCREL
2424 ENUMDOC
2425 This is an 18-bit pc-relative reloc with
2426 the right 3 bits assumed to be 0.
2427 ENUM
2428 BFD_RELOC_D30V_21_PCREL_R
2429 ENUMDOC
2430 This is an 18-bit pc-relative reloc with
2431 the right 3 bits assumed to be 0. Same
2432 as the previous reloc but on the right side
2433 of the container.
2434 ENUM
2435 BFD_RELOC_D30V_32
2436 ENUMDOC
2437 This is a 32-bit absolute reloc.
2438 ENUM
2439 BFD_RELOC_D30V_32_PCREL
2440 ENUMDOC
2441 This is a 32-bit pc-relative reloc.
2443 ENUM
2444 BFD_RELOC_M32R_24
2445 ENUMDOC
2446 Mitsubishi M32R relocs.
2447 This is a 24 bit absolute address.
2448 ENUM
2449 BFD_RELOC_M32R_10_PCREL
2450 ENUMDOC
2451 This is a 10-bit pc-relative reloc with the right 2 bits assumed to be 0.
2452 ENUM
2453 BFD_RELOC_M32R_18_PCREL
2454 ENUMDOC
2455 This is an 18-bit reloc with the right 2 bits assumed to be 0.
2456 ENUM
2457 BFD_RELOC_M32R_26_PCREL
2458 ENUMDOC
2459 This is a 26-bit reloc with the right 2 bits assumed to be 0.
2460 ENUM
2461 BFD_RELOC_M32R_HI16_ULO
2462 ENUMDOC
2463 This is a 16-bit reloc containing the high 16 bits of an address
2464 used when the lower 16 bits are treated as unsigned.
2465 ENUM
2466 BFD_RELOC_M32R_HI16_SLO
2467 ENUMDOC
2468 This is a 16-bit reloc containing the high 16 bits of an address
2469 used when the lower 16 bits are treated as signed.
2470 ENUM
2471 BFD_RELOC_M32R_LO16
2472 ENUMDOC
2473 This is a 16-bit reloc containing the lower 16 bits of an address.
2474 ENUM
2475 BFD_RELOC_M32R_SDA16
2476 ENUMDOC
2477 This is a 16-bit reloc containing the small data area offset for use in
2478 add3, load, and store instructions.
2480 ENUM
2481 BFD_RELOC_V850_9_PCREL
2482 ENUMDOC
2483 This is a 9-bit reloc
2484 ENUM
2485 BFD_RELOC_V850_22_PCREL
2486 ENUMDOC
2487 This is a 22-bit reloc
2489 ENUM
2490 BFD_RELOC_V850_SDA_16_16_OFFSET
2491 ENUMDOC
2492 This is a 16 bit offset from the short data area pointer.
2493 ENUM
2494 BFD_RELOC_V850_SDA_15_16_OFFSET
2495 ENUMDOC
2496 This is a 16 bit offset (of which only 15 bits are used) from the
2497 short data area pointer.
2498 ENUM
2499 BFD_RELOC_V850_ZDA_16_16_OFFSET
2500 ENUMDOC
2501 This is a 16 bit offset from the zero data area pointer.
2502 ENUM
2503 BFD_RELOC_V850_ZDA_15_16_OFFSET
2504 ENUMDOC
2505 This is a 16 bit offset (of which only 15 bits are used) from the
2506 zero data area pointer.
2507 ENUM
2508 BFD_RELOC_V850_TDA_6_8_OFFSET
2509 ENUMDOC
2510 This is an 8 bit offset (of which only 6 bits are used) from the
2511 tiny data area pointer.
2512 ENUM
2513 BFD_RELOC_V850_TDA_7_8_OFFSET
2514 ENUMDOC
2515 This is an 8bit offset (of which only 7 bits are used) from the tiny
2516 data area pointer.
2517 ENUM
2518 BFD_RELOC_V850_TDA_7_7_OFFSET
2519 ENUMDOC
2520 This is a 7 bit offset from the tiny data area pointer.
2521 ENUM
2522 BFD_RELOC_V850_TDA_16_16_OFFSET
2523 ENUMDOC
2524 This is a 16 bit offset from the tiny data area pointer.
2525 COMMENT
2526 ENUM
2527 BFD_RELOC_V850_TDA_4_5_OFFSET
2528 ENUMDOC
2529 This is a 5 bit offset (of which only 4 bits are used) from the tiny
2530 data area pointer.
2531 ENUM
2532 BFD_RELOC_V850_TDA_4_4_OFFSET
2533 ENUMDOC
2534 This is a 4 bit offset from the tiny data area pointer.
2535 ENUM
2536 BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET
2537 ENUMDOC
2538 This is a 16 bit offset from the short data area pointer, with the
2539 bits placed non-contigously in the instruction.
2540 ENUM
2541 BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET
2542 ENUMDOC
2543 This is a 16 bit offset from the zero data area pointer, with the
2544 bits placed non-contigously in the instruction.
2545 ENUM
2546 BFD_RELOC_V850_CALLT_6_7_OFFSET
2547 ENUMDOC
2548 This is a 6 bit offset from the call table base pointer.
2549 ENUM
2550 BFD_RELOC_V850_CALLT_16_16_OFFSET
2551 ENUMDOC
2552 This is a 16 bit offset from the call table base pointer.
2553 COMMENT
2555 ENUM
2556 BFD_RELOC_MN10300_32_PCREL
2557 ENUMDOC
2558 This is a 32bit pcrel reloc for the mn10300, offset by two bytes in the
2559 instruction.
2560 ENUM
2561 BFD_RELOC_MN10300_16_PCREL
2562 ENUMDOC
2563 This is a 16bit pcrel reloc for the mn10300, offset by two bytes in the
2564 instruction.
2566 ENUM
2567 BFD_RELOC_TIC30_LDP
2568 ENUMDOC
2569 This is a 8bit DP reloc for the tms320c30, where the most
2570 significant 8 bits of a 24 bit word are placed into the least
2571 significant 8 bits of the opcode.
2573 ENUM
2574 BFD_RELOC_TIC54X_PARTLS7
2575 ENUMDOC
2576 This is a 7bit reloc for the tms320c54x, where the least
2577 significant 7 bits of a 16 bit word are placed into the least
2578 significant 7 bits of the opcode.
2580 ENUM
2581 BFD_RELOC_TIC54X_PARTMS9
2582 ENUMDOC
2583 This is a 9bit DP reloc for the tms320c54x, where the most
2584 significant 9 bits of a 16 bit word are placed into the least
2585 significant 9 bits of the opcode.
2587 ENUM
2588 BFD_RELOC_TIC54X_23
2589 ENUMDOC
2590 This is an extended address 23-bit reloc for the tms320c54x.
2592 ENUM
2593 BFD_RELOC_TIC54X_16_OF_23
2594 ENUMDOC
2595 This is a 16-bit reloc for the tms320c54x, where the least
2596 significant 16 bits of a 23-bit extended address are placed into
2597 the opcode.
2599 ENUM
2600 BFD_RELOC_TIC54X_MS7_OF_23
2601 ENUMDOC
2602 This is a reloc for the tms320c54x, where the most
2603 significant 7 bits of a 23-bit extended address are placed into
2604 the opcode.
2606 ENUM
2607 BFD_RELOC_FR30_48
2608 ENUMDOC
2609 This is a 48 bit reloc for the FR30 that stores 32 bits.
2610 ENUM
2611 BFD_RELOC_FR30_20
2612 ENUMDOC
2613 This is a 32 bit reloc for the FR30 that stores 20 bits split up into
2614 two sections.
2615 ENUM
2616 BFD_RELOC_FR30_6_IN_4
2617 ENUMDOC
2618 This is a 16 bit reloc for the FR30 that stores a 6 bit word offset in
2619 4 bits.
2620 ENUM
2621 BFD_RELOC_FR30_8_IN_8
2622 ENUMDOC
2623 This is a 16 bit reloc for the FR30 that stores an 8 bit byte offset
2624 into 8 bits.
2625 ENUM
2626 BFD_RELOC_FR30_9_IN_8
2627 ENUMDOC
2628 This is a 16 bit reloc for the FR30 that stores a 9 bit short offset
2629 into 8 bits.
2630 ENUM
2631 BFD_RELOC_FR30_10_IN_8
2632 ENUMDOC
2633 This is a 16 bit reloc for the FR30 that stores a 10 bit word offset
2634 into 8 bits.
2635 ENUM
2636 BFD_RELOC_FR30_9_PCREL
2637 ENUMDOC
2638 This is a 16 bit reloc for the FR30 that stores a 9 bit pc relative
2639 short offset into 8 bits.
2640 ENUM
2641 BFD_RELOC_FR30_12_PCREL
2642 ENUMDOC
2643 This is a 16 bit reloc for the FR30 that stores a 12 bit pc relative
2644 short offset into 11 bits.
2646 ENUM
2647 BFD_RELOC_MCORE_PCREL_IMM8BY4
2648 ENUMX
2649 BFD_RELOC_MCORE_PCREL_IMM11BY2
2650 ENUMX
2651 BFD_RELOC_MCORE_PCREL_IMM4BY2
2652 ENUMX
2653 BFD_RELOC_MCORE_PCREL_32
2654 ENUMX
2655 BFD_RELOC_MCORE_PCREL_JSR_IMM11BY2
2656 ENUMX
2657 BFD_RELOC_MCORE_RVA
2658 ENUMDOC
2659 Motorola Mcore relocations.
2661 ENUM
2662 BFD_RELOC_AVR_7_PCREL
2663 ENUMDOC
2664 This is a 16 bit reloc for the AVR that stores 8 bit pc relative
2665 short offset into 7 bits.
2666 ENUM
2667 BFD_RELOC_AVR_13_PCREL
2668 ENUMDOC
2669 This is a 16 bit reloc for the AVR that stores 13 bit pc relative
2670 short offset into 12 bits.
2671 ENUM
2672 BFD_RELOC_AVR_16_PM
2673 ENUMDOC
2674 This is a 16 bit reloc for the AVR that stores 17 bit value (usually
2675 program memory address) into 16 bits.
2676 ENUM
2677 BFD_RELOC_AVR_LO8_LDI
2678 ENUMDOC
2679 This is a 16 bit reloc for the AVR that stores 8 bit value (usually
2680 data memory address) into 8 bit immediate value of LDI insn.
2681 ENUM
2682 BFD_RELOC_AVR_HI8_LDI
2683 ENUMDOC
2684 This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 bit
2685 of data memory address) into 8 bit immediate value of LDI insn.
2686 ENUM
2687 BFD_RELOC_AVR_HH8_LDI
2688 ENUMDOC
2689 This is a 16 bit reloc for the AVR that stores 8 bit value (most high 8 bit
2690 of program memory address) into 8 bit immediate value of LDI insn.
2691 ENUM
2692 BFD_RELOC_AVR_LO8_LDI_NEG
2693 ENUMDOC
2694 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2695 (usually data memory address) into 8 bit immediate value of SUBI insn.
2696 ENUM
2697 BFD_RELOC_AVR_HI8_LDI_NEG
2698 ENUMDOC
2699 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2700 (high 8 bit of data memory address) into 8 bit immediate value of
2701 SUBI insn.
2702 ENUM
2703 BFD_RELOC_AVR_HH8_LDI_NEG
2704 ENUMDOC
2705 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2706 (most high 8 bit of program memory address) into 8 bit immediate value
2707 of LDI or SUBI insn.
2708 ENUM
2709 BFD_RELOC_AVR_LO8_LDI_PM
2710 ENUMDOC
2711 This is a 16 bit reloc for the AVR that stores 8 bit value (usually
2712 command address) into 8 bit immediate value of LDI insn.
2713 ENUM
2714 BFD_RELOC_AVR_HI8_LDI_PM
2715 ENUMDOC
2716 This is a 16 bit reloc for the AVR that stores 8 bit value (high 8 bit
2717 of command address) into 8 bit immediate value of LDI insn.
2718 ENUM
2719 BFD_RELOC_AVR_HH8_LDI_PM
2720 ENUMDOC
2721 This is a 16 bit reloc for the AVR that stores 8 bit value (most high 8 bit
2722 of command address) into 8 bit immediate value of LDI insn.
2723 ENUM
2724 BFD_RELOC_AVR_LO8_LDI_PM_NEG
2725 ENUMDOC
2726 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2727 (usually command address) into 8 bit immediate value of SUBI insn.
2728 ENUM
2729 BFD_RELOC_AVR_HI8_LDI_PM_NEG
2730 ENUMDOC
2731 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2732 (high 8 bit of 16 bit command address) into 8 bit immediate value
2733 of SUBI insn.
2734 ENUM
2735 BFD_RELOC_AVR_HH8_LDI_PM_NEG
2736 ENUMDOC
2737 This is a 16 bit reloc for the AVR that stores negated 8 bit value
2738 (high 6 bit of 22 bit command address) into 8 bit immediate
2739 value of SUBI insn.
2740 ENUM
2741 BFD_RELOC_AVR_CALL
2742 ENUMDOC
2743 This is a 32 bit reloc for the AVR that stores 23 bit value
2744 into 22 bits.
2746 ENUM
2747 BFD_RELOC_390_12
2748 ENUMDOC
2749 Direct 12 bit.
2750 ENUM
2751 BFD_RELOC_390_GOT12
2752 ENUMDOC
2753 12 bit GOT offset.
2754 ENUM
2755 BFD_RELOC_390_PLT32
2756 ENUMDOC
2757 32 bit PC relative PLT address.
2758 ENUM
2759 BFD_RELOC_390_COPY
2760 ENUMDOC
2761 Copy symbol at runtime.
2762 ENUM
2763 BFD_RELOC_390_GLOB_DAT
2764 ENUMDOC
2765 Create GOT entry.
2766 ENUM
2767 BFD_RELOC_390_JMP_SLOT
2768 ENUMDOC
2769 Create PLT entry.
2770 ENUM
2771 BFD_RELOC_390_RELATIVE
2772 ENUMDOC
2773 Adjust by program base.
2774 ENUM
2775 BFD_RELOC_390_GOTPC
2776 ENUMDOC
2777 32 bit PC relative offset to GOT.
2778 ENUM
2779 BFD_RELOC_390_GOT16
2780 ENUMDOC
2781 16 bit GOT offset.
2782 ENUM
2783 BFD_RELOC_390_PC16DBL
2784 ENUMDOC
2785 PC relative 16 bit shifted by 1.
2786 ENUM
2787 BFD_RELOC_390_PLT16DBL
2788 ENUMDOC
2789 16 bit PC rel. PLT shifted by 1.
2790 ENUM
2791 BFD_RELOC_390_PC32DBL
2792 ENUMDOC
2793 PC relative 32 bit shifted by 1.
2794 ENUM
2795 BFD_RELOC_390_PLT32DBL
2796 ENUMDOC
2797 32 bit PC rel. PLT shifted by 1.
2798 ENUM
2799 BFD_RELOC_390_GOTPCDBL
2800 ENUMDOC
2801 32 bit PC rel. GOT shifted by 1.
2802 ENUM
2803 BFD_RELOC_390_GOT64
2804 ENUMDOC
2805 64 bit GOT offset.
2806 ENUM
2807 BFD_RELOC_390_PLT64
2808 ENUMDOC
2809 64 bit PC relative PLT address.
2810 ENUM
2811 BFD_RELOC_390_GOTENT
2812 ENUMDOC
2813 32 bit rel. offset to GOT entry.
2815 ENUM
2816 BFD_RELOC_VTABLE_INHERIT
2817 ENUMX
2818 BFD_RELOC_VTABLE_ENTRY
2819 ENUMDOC
2820 These two relocations are used by the linker to determine which of
2821 the entries in a C++ virtual function table are actually used. When
2822 the --gc-sections option is given, the linker will zero out the entries
2823 that are not used, so that the code for those functions need not be
2824 included in the output.
2826 VTABLE_INHERIT is a zero-space relocation used to describe to the
2827 linker the inheritence tree of a C++ virtual function table. The
2828 relocation's symbol should be the parent class' vtable, and the
2829 relocation should be located at the child vtable.
2831 VTABLE_ENTRY is a zero-space relocation that describes the use of a
2832 virtual function table entry. The reloc's symbol should refer to the
2833 table of the class mentioned in the code. Off of that base, an offset
2834 describes the entry that is being used. For Rela hosts, this offset
2835 is stored in the reloc's addend. For Rel hosts, we are forced to put
2836 this offset in the reloc's section offset.
2838 ENUM
2839 BFD_RELOC_IA64_IMM14
2840 ENUMX
2841 BFD_RELOC_IA64_IMM22
2842 ENUMX
2843 BFD_RELOC_IA64_IMM64
2844 ENUMX
2845 BFD_RELOC_IA64_DIR32MSB
2846 ENUMX
2847 BFD_RELOC_IA64_DIR32LSB
2848 ENUMX
2849 BFD_RELOC_IA64_DIR64MSB
2850 ENUMX
2851 BFD_RELOC_IA64_DIR64LSB
2852 ENUMX
2853 BFD_RELOC_IA64_GPREL22
2854 ENUMX
2855 BFD_RELOC_IA64_GPREL64I
2856 ENUMX
2857 BFD_RELOC_IA64_GPREL32MSB
2858 ENUMX
2859 BFD_RELOC_IA64_GPREL32LSB
2860 ENUMX
2861 BFD_RELOC_IA64_GPREL64MSB
2862 ENUMX
2863 BFD_RELOC_IA64_GPREL64LSB
2864 ENUMX
2865 BFD_RELOC_IA64_LTOFF22
2866 ENUMX
2867 BFD_RELOC_IA64_LTOFF64I
2868 ENUMX
2869 BFD_RELOC_IA64_PLTOFF22
2870 ENUMX
2871 BFD_RELOC_IA64_PLTOFF64I
2872 ENUMX
2873 BFD_RELOC_IA64_PLTOFF64MSB
2874 ENUMX
2875 BFD_RELOC_IA64_PLTOFF64LSB
2876 ENUMX
2877 BFD_RELOC_IA64_FPTR64I
2878 ENUMX
2879 BFD_RELOC_IA64_FPTR32MSB
2880 ENUMX
2881 BFD_RELOC_IA64_FPTR32LSB
2882 ENUMX
2883 BFD_RELOC_IA64_FPTR64MSB
2884 ENUMX
2885 BFD_RELOC_IA64_FPTR64LSB
2886 ENUMX
2887 BFD_RELOC_IA64_PCREL21B
2888 ENUMX
2889 BFD_RELOC_IA64_PCREL21BI
2890 ENUMX
2891 BFD_RELOC_IA64_PCREL21M
2892 ENUMX
2893 BFD_RELOC_IA64_PCREL21F
2894 ENUMX
2895 BFD_RELOC_IA64_PCREL22
2896 ENUMX
2897 BFD_RELOC_IA64_PCREL60B
2898 ENUMX
2899 BFD_RELOC_IA64_PCREL64I
2900 ENUMX
2901 BFD_RELOC_IA64_PCREL32MSB
2902 ENUMX
2903 BFD_RELOC_IA64_PCREL32LSB
2904 ENUMX
2905 BFD_RELOC_IA64_PCREL64MSB
2906 ENUMX
2907 BFD_RELOC_IA64_PCREL64LSB
2908 ENUMX
2909 BFD_RELOC_IA64_LTOFF_FPTR22
2910 ENUMX
2911 BFD_RELOC_IA64_LTOFF_FPTR64I
2912 ENUMX
2913 BFD_RELOC_IA64_LTOFF_FPTR64MSB
2914 ENUMX
2915 BFD_RELOC_IA64_LTOFF_FPTR64LSB
2916 ENUMX
2917 BFD_RELOC_IA64_SEGREL32MSB
2918 ENUMX
2919 BFD_RELOC_IA64_SEGREL32LSB
2920 ENUMX
2921 BFD_RELOC_IA64_SEGREL64MSB
2922 ENUMX
2923 BFD_RELOC_IA64_SEGREL64LSB
2924 ENUMX
2925 BFD_RELOC_IA64_SECREL32MSB
2926 ENUMX
2927 BFD_RELOC_IA64_SECREL32LSB
2928 ENUMX
2929 BFD_RELOC_IA64_SECREL64MSB
2930 ENUMX
2931 BFD_RELOC_IA64_SECREL64LSB
2932 ENUMX
2933 BFD_RELOC_IA64_REL32MSB
2934 ENUMX
2935 BFD_RELOC_IA64_REL32LSB
2936 ENUMX
2937 BFD_RELOC_IA64_REL64MSB
2938 ENUMX
2939 BFD_RELOC_IA64_REL64LSB
2940 ENUMX
2941 BFD_RELOC_IA64_LTV32MSB
2942 ENUMX
2943 BFD_RELOC_IA64_LTV32LSB
2944 ENUMX
2945 BFD_RELOC_IA64_LTV64MSB
2946 ENUMX
2947 BFD_RELOC_IA64_LTV64LSB
2948 ENUMX
2949 BFD_RELOC_IA64_IPLTMSB
2950 ENUMX
2951 BFD_RELOC_IA64_IPLTLSB
2952 ENUMX
2953 BFD_RELOC_IA64_COPY
2954 ENUMX
2955 BFD_RELOC_IA64_TPREL22
2956 ENUMX
2957 BFD_RELOC_IA64_TPREL64MSB
2958 ENUMX
2959 BFD_RELOC_IA64_TPREL64LSB
2960 ENUMX
2961 BFD_RELOC_IA64_LTOFF_TP22
2962 ENUMX
2963 BFD_RELOC_IA64_LTOFF22X
2964 ENUMX
2965 BFD_RELOC_IA64_LDXMOV
2966 ENUMDOC
2967 Intel IA64 Relocations.
2969 ENUM
2970 BFD_RELOC_M68HC11_HI8
2971 ENUMDOC
2972 Motorola 68HC11 reloc.
2973 This is the 8 bits high part of an absolute address.
2974 ENUM
2975 BFD_RELOC_M68HC11_LO8
2976 ENUMDOC
2977 Motorola 68HC11 reloc.
2978 This is the 8 bits low part of an absolute address.
2979 ENUM
2980 BFD_RELOC_M68HC11_3B
2981 ENUMDOC
2982 Motorola 68HC11 reloc.
2983 This is the 3 bits of a value.
2985 ENUM
2986 BFD_RELOC_CRIS_BDISP8
2987 ENUMX
2988 BFD_RELOC_CRIS_UNSIGNED_5
2989 ENUMX
2990 BFD_RELOC_CRIS_SIGNED_6
2991 ENUMX
2992 BFD_RELOC_CRIS_UNSIGNED_6
2993 ENUMX
2994 BFD_RELOC_CRIS_UNSIGNED_4
2995 ENUMDOC
2996 These relocs are only used within the CRIS assembler. They are not
2997 (at present) written to any object files.
2998 ENUM
2999 BFD_RELOC_CRIS_COPY
3000 ENUMX
3001 BFD_RELOC_CRIS_GLOB_DAT
3002 ENUMX
3003 BFD_RELOC_CRIS_JUMP_SLOT
3004 ENUMX
3005 BFD_RELOC_CRIS_RELATIVE
3006 ENUMDOC
3007 Relocs used in ELF shared libraries for CRIS.
3008 ENUM
3009 BFD_RELOC_CRIS_32_GOT
3010 ENUMDOC
3011 32-bit offset to symbol-entry within GOT.
3012 ENUM
3013 BFD_RELOC_CRIS_16_GOT
3014 ENUMDOC
3015 16-bit offset to symbol-entry within GOT.
3016 ENUM
3017 BFD_RELOC_CRIS_32_GOTPLT
3018 ENUMDOC
3019 32-bit offset to symbol-entry within GOT, with PLT handling.
3020 ENUM
3021 BFD_RELOC_CRIS_16_GOTPLT
3022 ENUMDOC
3023 16-bit offset to symbol-entry within GOT, with PLT handling.
3024 ENUM
3025 BFD_RELOC_CRIS_32_GOTREL
3026 ENUMDOC
3027 32-bit offset to symbol, relative to GOT.
3028 ENUM
3029 BFD_RELOC_CRIS_32_PLT_GOTREL
3030 ENUMDOC
3031 32-bit offset to symbol with PLT entry, relative to GOT.
3032 ENUM
3033 BFD_RELOC_CRIS_32_PLT_PCREL
3034 ENUMDOC
3035 32-bit offset to symbol with PLT entry, relative to this relocation.
3037 ENUM
3038 BFD_RELOC_860_COPY
3039 ENUMX
3040 BFD_RELOC_860_GLOB_DAT
3041 ENUMX
3042 BFD_RELOC_860_JUMP_SLOT
3043 ENUMX
3044 BFD_RELOC_860_RELATIVE
3045 ENUMX
3046 BFD_RELOC_860_PC26
3047 ENUMX
3048 BFD_RELOC_860_PLT26
3049 ENUMX
3050 BFD_RELOC_860_PC16
3051 ENUMX
3052 BFD_RELOC_860_LOW0
3053 ENUMX
3054 BFD_RELOC_860_SPLIT0
3055 ENUMX
3056 BFD_RELOC_860_LOW1
3057 ENUMX
3058 BFD_RELOC_860_SPLIT1
3059 ENUMX
3060 BFD_RELOC_860_LOW2
3061 ENUMX
3062 BFD_RELOC_860_SPLIT2
3063 ENUMX
3064 BFD_RELOC_860_LOW3
3065 ENUMX
3066 BFD_RELOC_860_LOGOT0
3067 ENUMX
3068 BFD_RELOC_860_SPGOT0
3069 ENUMX
3070 BFD_RELOC_860_LOGOT1
3071 ENUMX
3072 BFD_RELOC_860_SPGOT1
3073 ENUMX
3074 BFD_RELOC_860_LOGOTOFF0
3075 ENUMX
3076 BFD_RELOC_860_SPGOTOFF0
3077 ENUMX
3078 BFD_RELOC_860_LOGOTOFF1
3079 ENUMX
3080 BFD_RELOC_860_SPGOTOFF1
3081 ENUMX
3082 BFD_RELOC_860_LOGOTOFF2
3083 ENUMX
3084 BFD_RELOC_860_LOGOTOFF3
3085 ENUMX
3086 BFD_RELOC_860_LOPC
3087 ENUMX
3088 BFD_RELOC_860_HIGHADJ
3089 ENUMX
3090 BFD_RELOC_860_HAGOT
3091 ENUMX
3092 BFD_RELOC_860_HAGOTOFF
3093 ENUMX
3094 BFD_RELOC_860_HAPC
3095 ENUMX
3096 BFD_RELOC_860_HIGH
3097 ENUMX
3098 BFD_RELOC_860_HIGOT
3099 ENUMX
3100 BFD_RELOC_860_HIGOTOFF
3101 ENUMDOC
3102 Intel i860 Relocations.
3104 ENUM
3105 BFD_RELOC_OPENRISC_ABS_26
3106 ENUMX
3107 BFD_RELOC_OPENRISC_REL_26
3108 ENUMDOC
3109 OpenRISC Relocations.
3111 ENDSENUM
3112 BFD_RELOC_UNUSED
3113 CODE_FRAGMENT
3115 .typedef enum bfd_reloc_code_real bfd_reloc_code_real_type;
3119 FUNCTION
3120 bfd_reloc_type_lookup
3122 SYNOPSIS
3123 reloc_howto_type *
3124 bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
3126 DESCRIPTION
3127 Return a pointer to a howto structure which, when
3128 invoked, will perform the relocation @var{code} on data from the
3129 architecture noted.
3133 reloc_howto_type *
3134 bfd_reloc_type_lookup (abfd, code)
3135 bfd *abfd;
3136 bfd_reloc_code_real_type code;
3138 return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
3141 static reloc_howto_type bfd_howto_32 =
3142 HOWTO (0, 00, 2, 32, false, 0, complain_overflow_bitfield, 0, "VRT32", false, 0xffffffff, 0xffffffff, true);
3145 INTERNAL_FUNCTION
3146 bfd_default_reloc_type_lookup
3148 SYNOPSIS
3149 reloc_howto_type *bfd_default_reloc_type_lookup
3150 (bfd *abfd, bfd_reloc_code_real_type code);
3152 DESCRIPTION
3153 Provides a default relocation lookup routine for any architecture.
3157 reloc_howto_type *
3158 bfd_default_reloc_type_lookup (abfd, code)
3159 bfd *abfd;
3160 bfd_reloc_code_real_type code;
3162 switch (code)
3164 case BFD_RELOC_CTOR:
3165 /* The type of reloc used in a ctor, which will be as wide as the
3166 address - so either a 64, 32, or 16 bitter. */
3167 switch (bfd_get_arch_info (abfd)->bits_per_address)
3169 case 64:
3170 BFD_FAIL ();
3171 case 32:
3172 return &bfd_howto_32;
3173 case 16:
3174 BFD_FAIL ();
3175 default:
3176 BFD_FAIL ();
3178 default:
3179 BFD_FAIL ();
3181 return (reloc_howto_type *) NULL;
3185 FUNCTION
3186 bfd_get_reloc_code_name
3188 SYNOPSIS
3189 const char *bfd_get_reloc_code_name (bfd_reloc_code_real_type code);
3191 DESCRIPTION
3192 Provides a printable name for the supplied relocation code.
3193 Useful mainly for printing error messages.
3196 const char *
3197 bfd_get_reloc_code_name (code)
3198 bfd_reloc_code_real_type code;
3200 if (code > BFD_RELOC_UNUSED)
3201 return 0;
3202 return bfd_reloc_code_real_names[(int)code];
3206 INTERNAL_FUNCTION
3207 bfd_generic_relax_section
3209 SYNOPSIS
3210 boolean bfd_generic_relax_section
3211 (bfd *abfd,
3212 asection *section,
3213 struct bfd_link_info *,
3214 boolean *);
3216 DESCRIPTION
3217 Provides default handling for relaxing for back ends which
3218 don't do relaxing -- i.e., does nothing.
3221 /*ARGSUSED*/
3222 boolean
3223 bfd_generic_relax_section (abfd, section, link_info, again)
3224 bfd *abfd ATTRIBUTE_UNUSED;
3225 asection *section ATTRIBUTE_UNUSED;
3226 struct bfd_link_info *link_info ATTRIBUTE_UNUSED;
3227 boolean *again;
3229 *again = false;
3230 return true;
3234 INTERNAL_FUNCTION
3235 bfd_generic_gc_sections
3237 SYNOPSIS
3238 boolean bfd_generic_gc_sections
3239 (bfd *, struct bfd_link_info *);
3241 DESCRIPTION
3242 Provides default handling for relaxing for back ends which
3243 don't do section gc -- i.e., does nothing.
3246 /*ARGSUSED*/
3247 boolean
3248 bfd_generic_gc_sections (abfd, link_info)
3249 bfd *abfd ATTRIBUTE_UNUSED;
3250 struct bfd_link_info *link_info ATTRIBUTE_UNUSED;
3252 return true;
3256 INTERNAL_FUNCTION
3257 bfd_generic_get_relocated_section_contents
3259 SYNOPSIS
3260 bfd_byte *
3261 bfd_generic_get_relocated_section_contents (bfd *abfd,
3262 struct bfd_link_info *link_info,
3263 struct bfd_link_order *link_order,
3264 bfd_byte *data,
3265 boolean relocateable,
3266 asymbol **symbols);
3268 DESCRIPTION
3269 Provides default handling of relocation effort for back ends
3270 which can't be bothered to do it efficiently.
3274 bfd_byte *
3275 bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data,
3276 relocateable, symbols)
3277 bfd *abfd;
3278 struct bfd_link_info *link_info;
3279 struct bfd_link_order *link_order;
3280 bfd_byte *data;
3281 boolean relocateable;
3282 asymbol **symbols;
3284 /* Get enough memory to hold the stuff */
3285 bfd *input_bfd = link_order->u.indirect.section->owner;
3286 asection *input_section = link_order->u.indirect.section;
3288 long reloc_size = bfd_get_reloc_upper_bound (input_bfd, input_section);
3289 arelent **reloc_vector = NULL;
3290 long reloc_count;
3292 if (reloc_size < 0)
3293 goto error_return;
3295 reloc_vector = (arelent **) bfd_malloc ((size_t) reloc_size);
3296 if (reloc_vector == NULL && reloc_size != 0)
3297 goto error_return;
3299 /* read in the section */
3300 if (!bfd_get_section_contents (input_bfd,
3301 input_section,
3302 (PTR) data,
3304 input_section->_raw_size))
3305 goto error_return;
3307 /* We're not relaxing the section, so just copy the size info */
3308 input_section->_cooked_size = input_section->_raw_size;
3309 input_section->reloc_done = true;
3311 reloc_count = bfd_canonicalize_reloc (input_bfd,
3312 input_section,
3313 reloc_vector,
3314 symbols);
3315 if (reloc_count < 0)
3316 goto error_return;
3318 if (reloc_count > 0)
3320 arelent **parent;
3321 for (parent = reloc_vector; *parent != (arelent *) NULL;
3322 parent++)
3324 char *error_message = (char *) NULL;
3325 bfd_reloc_status_type r =
3326 bfd_perform_relocation (input_bfd,
3327 *parent,
3328 (PTR) data,
3329 input_section,
3330 relocateable ? abfd : (bfd *) NULL,
3331 &error_message);
3333 if (relocateable)
3335 asection *os = input_section->output_section;
3337 /* A partial link, so keep the relocs */
3338 os->orelocation[os->reloc_count] = *parent;
3339 os->reloc_count++;
3342 if (r != bfd_reloc_ok)
3344 switch (r)
3346 case bfd_reloc_undefined:
3347 if (!((*link_info->callbacks->undefined_symbol)
3348 (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
3349 input_bfd, input_section, (*parent)->address,
3350 true)))
3351 goto error_return;
3352 break;
3353 case bfd_reloc_dangerous:
3354 BFD_ASSERT (error_message != (char *) NULL);
3355 if (!((*link_info->callbacks->reloc_dangerous)
3356 (link_info, error_message, input_bfd, input_section,
3357 (*parent)->address)))
3358 goto error_return;
3359 break;
3360 case bfd_reloc_overflow:
3361 if (!((*link_info->callbacks->reloc_overflow)
3362 (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr),
3363 (*parent)->howto->name, (*parent)->addend,
3364 input_bfd, input_section, (*parent)->address)))
3365 goto error_return;
3366 break;
3367 case bfd_reloc_outofrange:
3368 default:
3369 abort ();
3370 break;
3376 if (reloc_vector != NULL)
3377 free (reloc_vector);
3378 return data;
3380 error_return:
3381 if (reloc_vector != NULL)
3382 free (reloc_vector);
3383 return NULL;