aboutsummaryrefslogtreecommitdiff
path: root/bfd/reloc.c
blob: bfa7c8552735e430583b77f722e4466e3c1816c2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
/* BFD support for handling relocation entries.
   Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
   Written by Cygnus Support.

This file is part of BFD, the Binary File Descriptor library.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

/*
SECTION
	Relocations

	BFD maintains relocations in much the same was as it maintains
	symbols; they are left alone until required, then read in
	en-mass and traslated into an internal form. There is a common
	routine <<bfd_perform_relocation>> which acts upon the
	canonical form to to the actual fixup.

	Note that relocations are maintained on a per section basis,
	whilst symbols are maintained on a per BFD basis.

	All a back end has to do to fit the BFD interface is to create
	as many <<struct reloc_cache_entry>> as there are relocations
	in a particular section, and fill in the right bits:

@menu
@* typedef arelent::
@* howto manager::
@end menu

*/
#include "bfd.h"
#include "sysdep.h"
#include "libbfd.h"
#include "seclet.h"
/*
DOCDD
INODE
	typedef arelent, howto manager, Relocations, Relocations

SUBSECTION
	typedef arelent

	This is the structure of a relocation entry:

CODE_FRAGMENT
.
.typedef enum bfd_reloc_status 
.{
.       {* No errors detected *}
.  bfd_reloc_ok,
.
.       {* The relocation was performed, but there was an overflow. *}
.  bfd_reloc_overflow,
.
.       {* The address to relocate was not within the section supplied. *}
.  bfd_reloc_outofrange,
.
.       {* Used by special functions *}
.  bfd_reloc_continue,
.
.       {* Unused *}
.  bfd_reloc_notsupported,
.
.       {* Unsupported relocation size requested. *}
.  bfd_reloc_other,
.
.       {* The symbol to relocate against was undefined. *}
.  bfd_reloc_undefined,
.
.       {* The relocation was performed, but may not be ok - presently
.          generated only when linking i960 coff files with i960 b.out
.          symbols. *}
.  bfd_reloc_dangerous
. }
. bfd_reloc_status_type;
.
.
.typedef struct reloc_cache_entry 
.{
.       {* A pointer into the canonical table of pointers  *}
.  struct symbol_cache_entry **sym_ptr_ptr;
.
.       {* offset in section *}
.  bfd_size_type address;
.
.       {* addend for relocation value *}
.  bfd_vma addend;    
.
.       {* Pointer to how to perform the required relocation *}
.  CONST struct reloc_howto_struct *howto;
.
.} arelent;

*/

/*
DESCRIPTION

        Here is a description of each of the fields within a relent:

        o sym_ptr_ptr

        The symbol table pointer points to a pointer to the symbol
        associated with the relocation request. This would naturally
        be the pointer into the table returned by the back end's
        get_symtab action. @xref{Symbols}. The symbol is referenced
        through a pointer to a pointer so that tools like the linker
        can fix up all the symbols of the same name by modifying only
        one pointer. The relocation routine looks in the symbol and
        uses the base of the section the symbol is attached to and the
        value of the symbol as the initial relocation offset. If the
        symbol pointer is zero, then the section provided is looked up.

        o address

        The address field gives the offset in bytes from the base of
        the section data which owns the relocation record to the first
        byte of relocatable information. The actual data relocated
        will be relative to this point - for example, a relocation
        type which modifies the bottom two bytes of a four byte word
        would not touch the first byte pointed to in a big endian
        world.
	
	o addend

	The addend is a value provided by the back end to be added (!)
	to the relocation offset. Its interpretation is dependent upon
	the howto. For example, on the 68k the code:


|        char foo[];
|        main()
|                {
|                return foo[0x12345678];
|                }

        Could be compiled into:

|        linkw fp,#-4
|        moveb @@#12345678,d0
|        extbl d0
|        unlk fp
|        rts


        This could create a reloc pointing to foo, but leave the
        offset in the data (something like)


|RELOCATION RECORDS FOR [.text]:
|offset   type      value 
|00000006 32        _foo
|
|00000000 4e56 fffc          ; linkw fp,#-4
|00000004 1039 1234 5678     ; moveb @@#12345678,d0
|0000000a 49c0               ; extbl d0
|0000000c 4e5e               ; unlk fp
|0000000e 4e75               ; rts


        Using coff and an 88k, some instructions don't have enough
        space in them to represent the full address range, and
        pointers have to be loaded in two parts. So you'd get something like:


|        or.u     r13,r0,hi16(_foo+0x12345678)
|        ld.b     r2,r13,lo16(_foo+0x12345678)
|        jmp      r1


        This should create two relocs, both pointing to _foo, and with
        0x12340000 in their addend field. The data would consist of:


|RELOCATION RECORDS FOR [.text]:
|offset   type      value 
|00000002 HVRT16    _foo+0x12340000
|00000006 LVRT16    _foo+0x12340000

|00000000 5da05678           ; or.u r13,r0,0x5678
|00000004 1c4d5678           ; ld.b r2,r13,0x5678
|00000008 f400c001           ; jmp r1


        The relocation routine digs out the value from the data, adds
        it to the addend to get the original offset and then adds the
        value of _foo. Note that all 32 bits have to be kept around
        somewhere, to cope with carry from bit 15 to bit 16.

        One further example is the sparc and the a.out format. The
        sparc has a similar problem to the 88k, in that some
        instructions don't have room for an entire offset, but on the
        sparc the parts are created odd sized lumps. The designers of
        the a.out format chose not to use the data within the section
        for storing part of the offset; all the offset is kept within
        the reloc. Any thing in the data should be ignored. 

|        save %sp,-112,%sp
|        sethi %hi(_foo+0x12345678),%g2
|        ldsb [%g2+%lo(_foo+0x12345678)],%i0
|        ret
|        restore

        Both relocs contains a pointer to foo, and the offsets would
        contain junk.


|RELOCATION RECORDS FOR [.text]:
|offset   type      value 
|00000004 HI22      _foo+0x12345678
|00000008 LO10      _foo+0x12345678

|00000000 9de3bf90     ; save %sp,-112,%sp
|00000004 05000000     ; sethi %hi(_foo+0),%g2
|00000008 f048a000     ; ldsb [%g2+%lo(_foo+0)],%i0
|0000000c 81c7e008     ; ret
|00000010 81e80000     ; restore


        o howto 

        The howto field can be imagined as a
        relocation instruction. It is a pointer to a struct which
        contains information on what to do with all the other
        information in the reloc record and data section. A back end
        would normally have a relocation instruction set and turn
        relocations into pointers to the correct structure on input -
        but it would be possible to create each howto field on demand.
        
*/


/*
SUBSUBSECTION 
        <<reloc_howto_type>>

        The <<reloc_howto_type>> is a structure which contains all the
        information that BFD needs to know to tie up a back end's data.

CODE_FRAGMENT
.struct symbol_cache_entry;		{* Forward declaration *}
.
.typedef CONST struct reloc_howto_struct 
.{ 
.       {*  The type field has mainly a documetary use - the back end can
.           to what it wants with it, though the normally the back end's
.           external idea of what a reloc number would be would be stored
.           in this field. For example, the a PC relative word relocation
.           in a coff environment would have the type 023 - because that's
.           what the outside world calls a R_PCRWORD reloc. *}
.  unsigned int type;
.
.       {*  The value the final relocation is shifted right by. This drops
.           unwanted data from the relocation.  *}
.  unsigned int rightshift;
.
.       {*  The size of the item to be relocated - 0, is one byte, 1 is 2
.           bytes, 2 is four bytes.  A negative value indicates that the
.	    result is to be subtracted from the data.  *}
.  int size;
.
.       {*  Now obsolete?  But m68k-coff still uses it... *}
.  unsigned int bitsize;
.
.       {*  Notes that the relocation is relative to the location in the
.           data section of the addend. The relocation function will
.           subtract from the relocation value the address of the location
.           being relocated. *}
.  boolean pc_relative;
.
.  unsigned int bitpos;
.
.       {*  Now obsolete *}
.  boolean absolute;
.
.       {* Causes the relocation routine to return an error if overflow
.          is detected when relocating. *}
.  boolean complain_on_overflow;
.
.       {* If this field is non null, then the supplied function is
.          called rather than the normal function. This allows really
.          strange relocation methods to be accomodated (e.g., i960 callj
.          instructions). *}
.  bfd_reloc_status_type (*special_function) 
.				    PARAMS ((bfd *abfd,
.					     arelent *reloc_entry,
.                                            struct symbol_cache_entry *symbol,
.                                            PTR data,
.                                            asection *input_section, 
.                                            bfd *output_bfd));
.
.       {* The textual name of the relocation type. *}
.  char *name;
.
.       {* When performing a partial link, some formats must modify the
.          relocations rather than the data - this flag signals this.*}
.  boolean partial_inplace;
.
.       {* The src_mask is used to select what parts of the read in data
.          are to be used in the relocation sum.  E.g., if this was an 8 bit
.          bit of data which we read and relocated, this would be
.          0x000000ff. When we have relocs which have an addend, such as
.          sun4 extended relocs, the value in the offset part of a
.          relocating field is garbage so we never use it. In this case
.          the mask would be 0x00000000. *}
.  bfd_vma src_mask;
.
.       {* The dst_mask is what parts of the instruction are replaced
.          into the instruction. In most cases src_mask == dst_mask,
.          except in the above special case, where dst_mask would be
.          0x000000ff, and src_mask would be 0x00000000.   *}
.  bfd_vma dst_mask;           
.
.       {* When some formats create PC relative instructions, they leave
.          the value of the pc of the place being relocated in the offset
.          slot of the instruction, so that a PC relative relocation can
.          be made just by adding in an ordinary offset (e.g., sun3 a.out).
.          Some formats leave the displacement part of an instruction
.          empty (e.g., m88k bcs), this flag signals the fact.*}
.  boolean pcrel_offset;
.
.} reloc_howto_type;

*/

/*
FUNCTION
	the HOWTO macro

DESCRIPTION
	The HOWTO define is horrible and will go away.


.#define HOWTO(C, R,S,B, P, BI, ABS, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
.  {(unsigned)C,R,S,B, P, BI, ABS,O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}

DESCRIPTION
	And will be replaced with the totally magic way. But for the
	moment, we are compatible, so do it this way..


.#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,false,false,FUNCTION, NAME,false,0,0,IN)
.
DESCRIPTION
	Helper routine to turn a symbol into a relocation value.

.#define HOWTO_PREPARE(relocation, symbol)      \
.  {                                            \
.  if (symbol != (asymbol *)NULL) {             \
.    if (bfd_is_com_section (symbol->section)) { \
.      relocation = 0;                          \
.    }                                          \
.    else {                                     \
.      relocation = symbol->value;              \
.    }                                          \
.  }                                            \
.}                      

*/

/*
TYPEDEF
	reloc_chain

DESCRIPTION

	How relocs are tied together

.typedef unsigned char bfd_byte;
.
.typedef struct relent_chain {
.  arelent relent;
.  struct   relent_chain *next;
.} arelent_chain;

*/



/*
FUNCTION 
	bfd_perform_relocation

SYNOPSIS
	bfd_reloc_status_type
                bfd_perform_relocation
                        (bfd * abfd,
                        arelent *reloc_entry,
                        PTR data,
                        asection *input_section,
                        bfd *output_bfd);

DESCRIPTION
	If an output_bfd is supplied to this function the generated
	image will be relocatable, the relocations are copied to the
	output file after they have been changed to reflect the new
	state of the world. There are two ways of reflecting the
	results of partial linkage in an output file; by modifying the
	output data in place, and by modifying the relocation record.
	Some native formats (e.g., basic a.out and basic coff) have no
	way of specifying an addend in the relocation type, so the
	addend has to go in the output data.  This is no big deal
	since in these formats the output data slot will always be big
	enough for the addend. Complex reloc types with addends were
	invented to solve just this problem.

*/


bfd_reloc_status_type
DEFUN(bfd_perform_relocation,(abfd,
                              reloc_entry,
                              data,
                              input_section,
                              output_bfd),
      bfd *abfd AND
      arelent *reloc_entry AND
      PTR data AND
      asection *input_section AND
      bfd *output_bfd)
{
  bfd_vma relocation;
  bfd_reloc_status_type flag = bfd_reloc_ok;
  bfd_size_type addr = reloc_entry->address ;
  bfd_vma output_base = 0;
  reloc_howto_type *howto = reloc_entry->howto;
  asection *reloc_target_output_section ;

  asymbol *symbol;

  symbol = *( reloc_entry->sym_ptr_ptr);
  if ((symbol->section == &bfd_abs_section) 
      && output_bfd != (bfd *)NULL) 
    {
      reloc_entry->address += input_section->output_offset;
      return bfd_reloc_ok;
    }

  if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL)
    flag = bfd_reloc_undefined;

  /* If there is a function supplied to handle this relocation type,
     call it.  It'll return `bfd_reloc_continue' if further processing
     can be done.  */
  if (howto->special_function)
    {
      bfd_reloc_status_type cont;
      cont = howto->special_function (abfd, reloc_entry, symbol, data,
				      input_section, output_bfd);
      if (cont != bfd_reloc_continue)
	return cont;
    }

  /* Is the address of the relocation really within the section?  */
  if (reloc_entry->address > input_section->_cooked_size)
    return bfd_reloc_outofrange;

  /* Work out which section the relocation is targetted at and the
     initial relocation command value.  */

  /* Get symbol value.  (Common symbols are special.)  */
  if (bfd_is_com_section (symbol->section))
    relocation = 0;
  else
    relocation = symbol->value;


  reloc_target_output_section = symbol->section->output_section;

  /* Convert input-section-relative symbol value to absolute.  */
  if (output_bfd && howto->partial_inplace==false)
    output_base = 0;
  else
    output_base = reloc_target_output_section->vma;

  relocation += output_base + symbol->section->output_offset;

  /* Add in supplied addend.  */
  relocation += reloc_entry->addend;

  if (howto->pc_relative == true)
    {
      /* Anything which started out as pc relative should end up that
	 way too. 

	 There are two ways we can see a pcrel instruction. Sometimes
	 the pcrel displacement has been partially calculated, it
	 includes the distance from the start of the section to the
	 instruction in it (e.g., sun3), and sometimes the field is
	 totally blank - e.g., m88kbcs.  */

      relocation -= 
	input_section->output_section->vma + input_section->output_offset;

      if (howto->pcrel_offset == true)
	relocation -= reloc_entry->address;
    }

  if (output_bfd!= (bfd *)NULL) 
    {
      if ( howto->partial_inplace == false)  
	{
	  /* This is a partial relocation, and we want to apply the relocation
	     to the reloc entry rather than the raw data. Modify the reloc
	     inplace to reflect what we now know.  */
	  reloc_entry->addend = relocation;
	  reloc_entry->address +=  input_section->output_offset;
	  return flag;
	}
      else
	{
	  /* This is a partial relocation, but inplace, so modify the
	     reloc record a bit. 

	     If we've relocated with a symbol with a section, change
	     into a ref to the section belonging to the symbol.  */

	  reloc_entry->address += input_section->output_offset;

	  /* WTF?? */
	  if (abfd->xvec->flavour == bfd_target_coff_flavour) 
	    {
	      relocation -= reloc_entry->addend;
	      reloc_entry->addend = 0;
	    }
	  else
	    {
	      reloc_entry->addend = relocation;
	    }
	}
    }
  else 
    {
      reloc_entry->addend = 0;
    }


  if (howto->complain_on_overflow && howto->pc_relative)
    {
      /* We can detect overflow safely here */

      bfd_signed_vma reloc_max = (1 << (howto->bitsize - 1))-1;
      bfd_signed_vma reloc_min = ~(reloc_max);

      if ((bfd_signed_vma) relocation > reloc_max
	  || (bfd_signed_vma) relocation < reloc_min)
	{
	  flag = bfd_reloc_overflow;
	}
    }
  
  /* 
    Either we are relocating all the way, or we don't want to apply
    the relocation to the reloc entry (probably because there isn't
    any room in the output format to describe addends to relocs)
    */
  relocation >>= howto->rightshift;

  /* Shift everything up to where it's going to be used */
   
  relocation <<= howto->bitpos;

  /* Wait for the day when all have the mask in them */

  /* What we do:
     i instruction to be left alone
     o offset within instruction
     r relocation offset to apply
     S src mask
     D dst mask
     N ~dst mask
     A part 1
     B part 2
     R result
     
     Do this:
     i i i i i o o o o o        from bfd_get<size>
     and           S S S S S    to get the size offset we want
     +   r r r r r r r r r r  to get the final value to place
     and           D D D D D  to chop to right size
     -----------------------
     A A A A A 
     And this:
     ...   i i i i i o o o o o  from bfd_get<size>
     and   N N N N N            get instruction
     -----------------------
     ...   B B B B B
     
     And then:       
     B B B B B       
     or              A A A A A     
     -----------------------
     R R R R R R R R R R        put into bfd_put<size>
     */

#define DOIT(x) \
  x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) +  relocation) & howto->dst_mask))

   switch (howto->size)
     {
     case 0:
       {
	 char x = bfd_get_8(abfd, (char *)data + addr);
	 DOIT(x);
	 bfd_put_8(abfd,x, (unsigned char *) data + addr);
       }
       break;

     case 1:
       if (relocation)
	 {
	   short x = bfd_get_16(abfd, (bfd_byte *)data + addr);
	   DOIT(x);
	   bfd_put_16(abfd, x,   (unsigned char *)data + addr);
	 }
       break;
     case 2:
       if (relocation)
	 {
	   long  x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
	   DOIT (x);
	   bfd_put_32 (abfd, x, (bfd_byte *)data + addr);
	 }
       break;
     case -2:
       {
	 long  x = bfd_get_32(abfd, (bfd_byte *) data + addr);
	 relocation = -relocation;
	 DOIT(x);
	 bfd_put_32(abfd,x,    (bfd_byte *)data + addr);
       }
       break;

     case 3:

       /* Do nothing */
       break;
     default:
       return bfd_reloc_other;
     }

  return flag;
}



/*
DOCDD
INODE
	howto manager,  , typedef arelent, Relocations

SECTION
	The howto manager 

	When an application wants to create a relocation, but doesn't
	know what the target machine might call it, it can find out by
	using this bit of code.

*/

/*
TYPEDEF
	bfd_reloc_code_type

DESCRIPTION
	The insides of a reloc code

CODE_FRAGMENT
.
.typedef enum bfd_reloc_code_real 
.
.{
.	{* 64 bits wide, simple reloc *}
.  BFD_RELOC_64,
.	{* 64 bits, PC-relative *}
.  BFD_RELOC_64_PCREL,
.
.       {* 32 bits wide, simple reloc *}
.  BFD_RELOC_32,
.	{* 32 bits, PC-relative *}
.  BFD_RELOC_32_PCREL,
.
.       {* 16 bits wide, simple reloc *}
.  BFD_RELOC_16,        
.	{* 16 bits, PC-relative *}
.  BFD_RELOC_16_PCREL,
.
.       {* 8 bits wide, simple *}
.  BFD_RELOC_8,
.       {* 8 bits wide, pc relative *}
.  BFD_RELOC_8_PCREL,
.       {* 8 bits wide, but used to form an address like 0xffnn *}
.  BFD_RELOC_8_FFnn,
.
.       {* The type of reloc used to build a contructor table - at the
.          moment probably a 32 bit wide abs address, but the cpu can
.          choose. *}
.
.  BFD_RELOC_CTOR,
.
.	{* High 22 bits of 32-bit value; simple reloc.  *}
.  BFD_RELOC_HI22,
.	{* Low 10 bits.  *}
.  BFD_RELOC_LO10,
.
.	{* Reloc types used for i960/b.out.  *}
.  BFD_RELOC_24_PCREL,
.  BFD_RELOC_I960_CALLJ,
.
.	{* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
.	   word displacement, e.g. for SPARC) *}
.  BFD_RELOC_32_PCREL_S2,
.
.  {* now for the sparc/elf codes *}
.  BFD_RELOC_NONE,		{* actually used *}
.  BFD_RELOC_SPARC_WDISP22,
.  BFD_RELOC_SPARC22,
.  BFD_RELOC_SPARC13,
.  BFD_RELOC_SPARC_GOT10,
.  BFD_RELOC_SPARC_GOT13,
.  BFD_RELOC_SPARC_GOT22,
.  BFD_RELOC_SPARC_PC10,
.  BFD_RELOC_SPARC_PC22,
.  BFD_RELOC_SPARC_WPLT30,
.  BFD_RELOC_SPARC_COPY,
.  BFD_RELOC_SPARC_GLOB_DAT,
.  BFD_RELOC_SPARC_JMP_SLOT,
.  BFD_RELOC_SPARC_RELATIVE,
.  BFD_RELOC_SPARC_UA32,
.
.  {* this one is a.out specific? *}
.  BFD_RELOC_SPARC_BASE13,
.  BFD_RELOC_SPARC_BASE22,
.
.  {* start-sanitize-v9 *}
.  BFD_RELOC_SPARC_10,
.  BFD_RELOC_SPARC_11,
.#define  BFD_RELOC_SPARC_64 BFD_RELOC_64
.  BFD_RELOC_SPARC_OLO10,
.  BFD_RELOC_SPARC_HH22,
.  BFD_RELOC_SPARC_HM10,
.  BFD_RELOC_SPARC_LM22,
.  BFD_RELOC_SPARC_PC_HH22,
.  BFD_RELOC_SPARC_PC_HM10,
.  BFD_RELOC_SPARC_PC_LM22,
.  BFD_RELOC_SPARC_WDISP16,
.  BFD_RELOC_SPARC_WDISP19,
.  BFD_RELOC_SPARC_GLOB_JMP,
.  BFD_RELOC_SPARC_LO7,
.  {* end-sanitize-v9 *}
.
.       {* Bits 27..2 of the relocation address shifted right 2 bits;
.         simple reloc otherwise.  *}
.  BFD_RELOC_MIPS_JMP,
.
.       {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
.  BFD_RELOC_16_PCREL_S2,
.
.       {* High 16 bits of 32-bit value; simple reloc.  *}
.  BFD_RELOC_HI16,
.       {* High 16 bits of 32-bit value but the low 16 bits will be sign
.          extended and added to form the final result.  If the low 16
.          bits form a negative number, we need to add one to the high value
.          to compensate for the borrow when the low bits are added.  *}
.  BFD_RELOC_HI16_S,
.       {* Low 16 bits.  *}
.  BFD_RELOC_LO16,
.
.	{* 16 bit relocation relative to the global pointer.  *}
.  BFD_RELOC_MIPS_GPREL,
.
.       {* These are, so far, specific to HPPA processors.  I'm not sure that
.	   some don't duplicate other reloc types, such as BFD_RELOC_32 and
.	   _32_PCREL.  Also, many more were in the list I got that don't
.	   fit in well in the model BFD uses, so I've omitted them for now.
.	   If we do make this reloc type get used for code that really does
.	   implement the funky reloc types, they'll have to be added to this
.	   list.   *}
.  BFD_RELOC_HPPA_32,
.  BFD_RELOC_HPPA_11,
.  BFD_RELOC_HPPA_14,
.  BFD_RELOC_HPPA_17,
.  BFD_RELOC_HPPA_L21,
.  BFD_RELOC_HPPA_R11,
.  BFD_RELOC_HPPA_R14,
.  BFD_RELOC_HPPA_R17,
.  BFD_RELOC_HPPA_LS21,
.  BFD_RELOC_HPPA_RS11,
.  BFD_RELOC_HPPA_RS14,
.  BFD_RELOC_HPPA_RS17,
.  BFD_RELOC_HPPA_LD21,
.  BFD_RELOC_HPPA_RD11,
.  BFD_RELOC_HPPA_RD14,
.  BFD_RELOC_HPPA_RD17,
.  BFD_RELOC_HPPA_LR21,
.  BFD_RELOC_HPPA_RR14,
.  BFD_RELOC_HPPA_RR17,
.  BFD_RELOC_HPPA_GOTOFF_11,
.  BFD_RELOC_HPPA_GOTOFF_14,
.  BFD_RELOC_HPPA_GOTOFF_L21,
.  BFD_RELOC_HPPA_GOTOFF_R11,
.  BFD_RELOC_HPPA_GOTOFF_R14,
.  BFD_RELOC_HPPA_GOTOFF_LS21,
.  BFD_RELOC_HPPA_GOTOFF_RS11,
.  BFD_RELOC_HPPA_GOTOFF_RS14,
.  BFD_RELOC_HPPA_GOTOFF_LD21,
.  BFD_RELOC_HPPA_GOTOFF_RD11,
.  BFD_RELOC_HPPA_GOTOFF_RD14,
.  BFD_RELOC_HPPA_GOTOFF_LR21,
.  BFD_RELOC_HPPA_GOTOFF_RR14,
.  BFD_RELOC_HPPA_DLT_32,
.  BFD_RELOC_HPPA_DLT_11,
.  BFD_RELOC_HPPA_DLT_14,
.  BFD_RELOC_HPPA_DLT_L21,
.  BFD_RELOC_HPPA_DLT_R11,
.  BFD_RELOC_HPPA_DLT_R14,
.  BFD_RELOC_HPPA_ABS_CALL_11,
.  BFD_RELOC_HPPA_ABS_CALL_14,
.  BFD_RELOC_HPPA_ABS_CALL_17,
.  BFD_RELOC_HPPA_ABS_CALL_L21,
.  BFD_RELOC_HPPA_ABS_CALL_R11,
.  BFD_RELOC_HPPA_ABS_CALL_R14,
.  BFD_RELOC_HPPA_ABS_CALL_R17,
.  BFD_RELOC_HPPA_ABS_CALL_LS21,
.  BFD_RELOC_HPPA_ABS_CALL_RS11,
.  BFD_RELOC_HPPA_ABS_CALL_RS14,
.  BFD_RELOC_HPPA_ABS_CALL_RS17,
.  BFD_RELOC_HPPA_ABS_CALL_LD21,
.  BFD_RELOC_HPPA_ABS_CALL_RD11,
.  BFD_RELOC_HPPA_ABS_CALL_RD14,
.  BFD_RELOC_HPPA_ABS_CALL_RD17,
.  BFD_RELOC_HPPA_ABS_CALL_LR21,
.  BFD_RELOC_HPPA_ABS_CALL_RR14,
.  BFD_RELOC_HPPA_ABS_CALL_RR17,
.  BFD_RELOC_HPPA_PCREL_CALL_11,
.  BFD_RELOC_HPPA_PCREL_CALL_12,
.  BFD_RELOC_HPPA_PCREL_CALL_14,
.  BFD_RELOC_HPPA_PCREL_CALL_17,
.  BFD_RELOC_HPPA_PCREL_CALL_L21,
.  BFD_RELOC_HPPA_PCREL_CALL_R11,
.  BFD_RELOC_HPPA_PCREL_CALL_R14,
.  BFD_RELOC_HPPA_PCREL_CALL_R17,
.  BFD_RELOC_HPPA_PCREL_CALL_LS21,
.  BFD_RELOC_HPPA_PCREL_CALL_RS11,
.  BFD_RELOC_HPPA_PCREL_CALL_RS14,
.  BFD_RELOC_HPPA_PCREL_CALL_RS17,
.  BFD_RELOC_HPPA_PCREL_CALL_LD21,
.  BFD_RELOC_HPPA_PCREL_CALL_RD11,
.  BFD_RELOC_HPPA_PCREL_CALL_RD14,
.  BFD_RELOC_HPPA_PCREL_CALL_RD17,
.  BFD_RELOC_HPPA_PCREL_CALL_LR21,
.  BFD_RELOC_HPPA_PCREL_CALL_RR14,
.  BFD_RELOC_HPPA_PCREL_CALL_RR17,
.  BFD_RELOC_HPPA_PLABEL_32,
.  BFD_RELOC_HPPA_PLABEL_11,
.  BFD_RELOC_HPPA_PLABEL_14,
.  BFD_RELOC_HPPA_PLABEL_L21,
.  BFD_RELOC_HPPA_PLABEL_R11,
.  BFD_RELOC_HPPA_PLABEL_R14,
.  BFD_RELOC_HPPA_UNWIND_ENTRY,
.  BFD_RELOC_HPPA_UNWIND_ENTRIES,
.
.  {* this must be the highest numeric value *}
.  BFD_RELOC_UNUSED
. } bfd_reloc_code_real_type;
*/



/*
SECTION
	bfd_reloc_type_lookup

SYNOPSIS
	CONST struct reloc_howto_struct *
	bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);

DESCRIPTION
	This routine returns a pointer to a howto struct which when
	invoked, will perform the supplied relocation on data from the
	architecture noted.

*/


CONST struct reloc_howto_struct *
DEFUN(bfd_reloc_type_lookup,(abfd, code),
      bfd *abfd AND
      bfd_reloc_code_real_type code)
{
  return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
}

static reloc_howto_type bfd_howto_32 =
 HOWTO(0, 00,2,32,false,0,false,true,0,"VRT32", false,0xffffffff,0xffffffff,true);


/*
INTERNAL_FUNCTION
	bfd_default_reloc_type_lookup

SYNOPSIS
	CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
	(bfd *abfd AND
         bfd_reloc_code_real_type  code);

DESCRIPTION
	Provides a default relocation lookup routine for any architecture.


*/

CONST struct reloc_howto_struct *
DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
      bfd *abfd AND
      bfd_reloc_code_real_type code)
{
  switch (code) 
    {
    case BFD_RELOC_CTOR:
      /* The type of reloc used in a ctor, which will be as wide as the
	 address - so either a 64, 32, or 16 bitter.. */
      switch (bfd_get_arch_info (abfd)->bits_per_address) {
      case 64:
	BFD_FAIL();
      case 32:
	return &bfd_howto_32;
      case 16:
	BFD_FAIL();
      default:
	BFD_FAIL();
      }
    default:
      BFD_FAIL();
    }
  return (CONST struct reloc_howto_struct *)NULL;
}


/*
INTERNAL_FUNCTION
	bfd_generic_relax_section

SYNOPSIS
	boolean bfd_generic_relax_section
	 (bfd *abfd,
	  asection *section,
	  asymbol **symbols);

DESCRIPTION
	Provides default handling for relaxing for back ends which
	don't do relaxing -- i.e., does nothing.
*/

boolean
DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
      bfd *abfd AND
      asection *section AND
      asymbol **symbols)
{
  
  return false;
  
}

		
/*
INTERNAL_FUNCTION
	bfd_generic_get_relocated_section_contents

SYNOPSIS
	bfd_byte *
	   bfd_generic_get_relocated_section_contents (bfd *abfd,
	     struct bfd_seclet *seclet,
	     bfd_byte *data,
	     boolean relocateable);

DESCRIPTION
	Provides default handling of relocation effort for back ends
	which can't be bothered to do it efficiently.

*/

bfd_byte *
DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
						  seclet,
						  data,
						  relocateable),
      bfd *abfd AND
      struct bfd_seclet *seclet AND
      bfd_byte *data AND
      boolean relocateable)
{
  extern bfd_error_vector_type bfd_error_vector;

  /* Get enough memory to hold the stuff */
  bfd *input_bfd = seclet->u.indirect.section->owner;
  asection *input_section = seclet->u.indirect.section;



  size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
  arelent **reloc_vector = (arelent **) alloca(reloc_size);
  
  /* read in the section */
  bfd_get_section_contents(input_bfd,
			   input_section,
			   data,
			   0,
			   input_section->_raw_size);
  
/* We're not relaxing the section, so just copy the size info */
  input_section->_cooked_size = input_section->_raw_size;
  input_section->reloc_done = true;
  

  if (bfd_canonicalize_reloc(input_bfd, 
			     input_section,
			     reloc_vector,
			     seclet->u.indirect.symbols) )
  {
    arelent **parent;
    for (parent = reloc_vector;  * parent != (arelent *)NULL;
	 parent++) 
    { 
      bfd_reloc_status_type r=
       bfd_perform_relocation(input_bfd,
			      *parent,
			      data,
			      input_section,
			      relocateable ? abfd : (bfd *) NULL);
      
      if (relocateable)
	{
	  asection *os = input_section->output_section;

	  /* A partial link, so keep the relocs */
	  os->orelocation[os->reloc_count] = *parent;
	  os->reloc_count++;
	}

      if (r != bfd_reloc_ok) 
      {
	switch (r)
	{
	case bfd_reloc_undefined:
	  bfd_error_vector.undefined_symbol(*parent, seclet);
	  break;
	case bfd_reloc_dangerous: 
	  bfd_error_vector.reloc_dangerous(*parent, seclet);
	  break;
	case bfd_reloc_outofrange:
	case bfd_reloc_overflow:
	  bfd_error_vector.reloc_value_truncated(*parent, seclet);
	  break;
	default:
	  abort();
	  break;
	}

      }
    }    
  }


  return data;

  
}