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c618de01 1/* BFD support for handling relocation entries.
65cab589 2 Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
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3 Written by Cygnus Support.
4
5This file is part of BFD, the Binary File Descriptor library.
6
7This program is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2 of the License, or
10(at your option) any later version.
11
12This program is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with this program; if not, write to the Free Software
19Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
20
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21/*
22SECTION
23 Relocations
985fca12 24
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25 BFD maintains relocations in much the same was as it maintains
26 symbols; they are left alone until required, then read in
27 en-mass and traslated into an internal form. There is a common
28 routine <<bfd_perform_relocation>> which acts upon the
29 canonical form to to the actual fixup.
985fca12 30
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31 Note that relocations are maintained on a per section basis,
32 whilst symbols are maintained on a per BFD basis.
985fca12 33
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34 All a back end has to do to fit the BFD interface is to create
35 as many <<struct reloc_cache_entry>> as there are relocations
65cab589 36 in a particular section, and fill in the right bits:
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37
38@menu
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39@* typedef arelent::
40@* howto manager::
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41@end menu
42
43*/
985fca12 44#include "bfd.h"
0cda46cf 45#include "sysdep.h"
985fca12 46#include "libbfd.h"
e98e6ec1 47#include "seclet.h"
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48/*
49DOCDD
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50INODE
51 typedef arelent, howto manager, Relocations, Relocations
985fca12 52
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53SUBSECTION
54 typedef arelent
985fca12 55
e98e6ec1 56 This is the structure of a relocation entry:
985fca12 57
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58CODE_FRAGMENT
59.
60.typedef enum bfd_reloc_status
61.{
62. {* No errors detected *}
0cda46cf 63. bfd_reloc_ok,
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64.
65. {* The relocation was performed, but there was an overflow. *}
0cda46cf 66. bfd_reloc_overflow,
e98e6ec1 67.
65cab589 68. {* The address to relocate was not within the section supplied. *}
0cda46cf 69. bfd_reloc_outofrange,
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70.
71. {* Used by special functions *}
0cda46cf 72. bfd_reloc_continue,
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73.
74. {* Unused *}
0cda46cf 75. bfd_reloc_notsupported,
e98e6ec1 76.
65cab589 77. {* Unsupported relocation size requested. *}
0cda46cf 78. bfd_reloc_other,
e98e6ec1 79.
65cab589 80. {* The symbol to relocate against was undefined. *}
0cda46cf 81. bfd_reloc_undefined,
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82.
83. {* The relocation was performed, but may not be ok - presently
84. generated only when linking i960 coff files with i960 b.out
85. symbols. *}
0cda46cf 86. bfd_reloc_dangerous
e98e6ec1 87. }
0cda46cf 88. bfd_reloc_status_type;
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89.
90.
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91.typedef struct reloc_cache_entry
92.{
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93. {* A pointer into the canonical table of pointers *}
94. struct symbol_cache_entry **sym_ptr_ptr;
95.
96. {* offset in section *}
65cab589 97. bfd_size_type address;
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98.
99. {* addend for relocation value *}
100. bfd_vma addend;
101.
102. {* Pointer to how to perform the required relocation *}
103. CONST struct reloc_howto_struct *howto;
104.
105.} arelent;
985fca12 106
e98e6ec1 107*/
985fca12 108
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109/*
110DESCRIPTION
985fca12 111
e98e6ec1 112 Here is a description of each of the fields within a relent:
985fca12 113
e98e6ec1 114 o sym_ptr_ptr
985fca12 115
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116 The symbol table pointer points to a pointer to the symbol
117 associated with the relocation request. This would naturally
118 be the pointer into the table returned by the back end's
119 get_symtab action. @xref{Symbols}. The symbol is referenced
120 through a pointer to a pointer so that tools like the linker
121 can fix up all the symbols of the same name by modifying only
122 one pointer. The relocation routine looks in the symbol and
123 uses the base of the section the symbol is attached to and the
124 value of the symbol as the initial relocation offset. If the
125 symbol pointer is zero, then the section provided is looked up.
985fca12 126
e98e6ec1 127 o address
985fca12 128
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129 The address field gives the offset in bytes from the base of
130 the section data which owns the relocation record to the first
131 byte of relocatable information. The actual data relocated
132 will be relative to this point - for example, a relocation
133 type which modifies the bottom two bytes of a four byte word
134 would not touch the first byte pointed to in a big endian
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135 world.
136
137 o addend
138
139 The addend is a value provided by the back end to be added (!)
140 to the relocation offset. Its interpretation is dependent upon
141 the howto. For example, on the 68k the code:
985fca12 142
985fca12 143
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144| char foo[];
145| main()
146| {
147| return foo[0x12345678];
148| }
985fca12 149
e98e6ec1 150 Could be compiled into:
985fca12 151
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152| linkw fp,#-4
153| moveb @@#12345678,d0
154| extbl d0
155| unlk fp
156| rts
985fca12 157
985fca12 158
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159 This could create a reloc pointing to foo, but leave the
160 offset in the data (something like)
0cda46cf 161
985fca12 162
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163|RELOCATION RECORDS FOR [.text]:
164|offset type value
165|00000006 32 _foo
166|
167|00000000 4e56 fffc ; linkw fp,#-4
168|00000004 1039 1234 5678 ; moveb @@#12345678,d0
169|0000000a 49c0 ; extbl d0
170|0000000c 4e5e ; unlk fp
171|0000000e 4e75 ; rts
0cda46cf 172
985fca12 173
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174 Using coff and an 88k, some instructions don't have enough
175 space in them to represent the full address range, and
176 pointers have to be loaded in two parts. So you'd get something like:
0cda46cf 177
985fca12 178
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179| or.u r13,r0,hi16(_foo+0x12345678)
180| ld.b r2,r13,lo16(_foo+0x12345678)
181| jmp r1
985fca12 182
985fca12 183
65cab589 184 This should create two relocs, both pointing to _foo, and with
e98e6ec1 185 0x12340000 in their addend field. The data would consist of:
0cda46cf 186
985fca12 187
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188|RELOCATION RECORDS FOR [.text]:
189|offset type value
190|00000002 HVRT16 _foo+0x12340000
191|00000006 LVRT16 _foo+0x12340000
985fca12 192
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193|00000000 5da05678 ; or.u r13,r0,0x5678
194|00000004 1c4d5678 ; ld.b r2,r13,0x5678
195|00000008 f400c001 ; jmp r1
985fca12 196
0cda46cf 197
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198 The relocation routine digs out the value from the data, adds
199 it to the addend to get the original offset and then adds the
200 value of _foo. Note that all 32 bits have to be kept around
201 somewhere, to cope with carry from bit 15 to bit 16.
985fca12 202
65cab589 203 One further example is the sparc and the a.out format. The
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204 sparc has a similar problem to the 88k, in that some
205 instructions don't have room for an entire offset, but on the
206 sparc the parts are created odd sized lumps. The designers of
207 the a.out format chose not to use the data within the section
208 for storing part of the offset; all the offset is kept within
209 the reloc. Any thing in the data should be ignored.
0cda46cf 210
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211| save %sp,-112,%sp
212| sethi %hi(_foo+0x12345678),%g2
213| ldsb [%g2+%lo(_foo+0x12345678)],%i0
214| ret
215| restore
0cda46cf 216
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217 Both relocs contains a pointer to foo, and the offsets would
218 contain junk.
985fca12 219
0cda46cf 220
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221|RELOCATION RECORDS FOR [.text]:
222|offset type value
223|00000004 HI22 _foo+0x12345678
224|00000008 LO10 _foo+0x12345678
225
226|00000000 9de3bf90 ; save %sp,-112,%sp
227|00000004 05000000 ; sethi %hi(_foo+0),%g2
228|00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0
229|0000000c 81c7e008 ; ret
230|00000010 81e80000 ; restore
231
0cda46cf 232
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233 o howto
234
235 The howto field can be imagined as a
236 relocation instruction. It is a pointer to a struct which
237 contains information on what to do with all the other
238 information in the reloc record and data section. A back end
239 would normally have a relocation instruction set and turn
240 relocations into pointers to the correct structure on input -
241 but it would be possible to create each howto field on demand.
242
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243*/
244
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245/*
246SUBSUBSECTION
247 <<enum complain_overflow>>
248
249 Indicates what sort of overflow checking should be done when
250 performing a relocation.
251
252CODE_FRAGMENT
253.
254.enum complain_overflow
255.{
256. {* Do not complain on overflow. *}
257. complain_overflow_dont,
258.
259. {* Complain if the bitfield overflows, whether it is considered
260. as signed or unsigned. *}
261. complain_overflow_bitfield,
262.
263. {* Complain if the value overflows when considered as signed
264. number. *}
265. complain_overflow_signed,
266.
267. {* Complain if the value overflows when considered as an
268. unsigned number. *}
269. complain_overflow_unsigned
270.};
271
272*/
985fca12 273
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274/*
275SUBSUBSECTION
e98e6ec1 276 <<reloc_howto_type>>
985fca12 277
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278 The <<reloc_howto_type>> is a structure which contains all the
279 information that BFD needs to know to tie up a back end's data.
985fca12 280
e98e6ec1 281CODE_FRAGMENT
5022aea5 282.struct symbol_cache_entry; {* Forward declaration *}
e98e6ec1 283.
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284.typedef CONST struct reloc_howto_struct
285.{
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286. {* The type field has mainly a documetary use - the back end can
287. to what it wants with it, though the normally the back end's
288. external idea of what a reloc number would be would be stored
289. in this field. For example, the a PC relative word relocation
290. in a coff environment would have the type 023 - because that's
291. what the outside world calls a R_PCRWORD reloc. *}
0cda46cf 292. unsigned int type;
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293.
294. {* The value the final relocation is shifted right by. This drops
295. unwanted data from the relocation. *}
0cda46cf 296. unsigned int rightshift;
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297.
298. {* The size of the item to be relocated - 0, is one byte, 1 is 2
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299. bytes, 2 is four bytes. A negative value indicates that the
300. result is to be subtracted from the data. *}
c26d7d17 301. int size;
e98e6ec1 302.
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303. {* The number of bits in the item to be relocated. This is used
304. when doing overflow checking. *}
0cda46cf 305. unsigned int bitsize;
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306.
307. {* Notes that the relocation is relative to the location in the
308. data section of the addend. The relocation function will
309. subtract from the relocation value the address of the location
310. being relocated. *}
0cda46cf 311. boolean pc_relative;
e98e6ec1 312.
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313. {* The bit position of the reloc value in the destination.
314. The relocated value is left shifted by this amount. *}
0cda46cf 315. unsigned int bitpos;
e98e6ec1 316.
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317. {* What type of overflow error should be checked for when
318. relocating. *}
319. enum complain_overflow complain_on_overflow;
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320.
321. {* If this field is non null, then the supplied function is
322. called rather than the normal function. This allows really
65cab589 323. strange relocation methods to be accomodated (e.g., i960 callj
e98e6ec1 324. instructions). *}
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325. bfd_reloc_status_type (*special_function)
326. PARAMS ((bfd *abfd,
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327. arelent *reloc_entry,
328. struct symbol_cache_entry *symbol,
329. PTR data,
8070f29d 330. asection *input_section,
fefb4b30 331. bfd *output_bfd));
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332.
333. {* The textual name of the relocation type. *}
0cda46cf 334. char *name;
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335.
336. {* When performing a partial link, some formats must modify the
337. relocations rather than the data - this flag signals this.*}
0cda46cf 338. boolean partial_inplace;
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339.
340. {* The src_mask is used to select what parts of the read in data
65cab589 341. are to be used in the relocation sum. E.g., if this was an 8 bit
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342. bit of data which we read and relocated, this would be
343. 0x000000ff. When we have relocs which have an addend, such as
344. sun4 extended relocs, the value in the offset part of a
345. relocating field is garbage so we never use it. In this case
346. the mask would be 0x00000000. *}
65cab589 347. bfd_vma src_mask;
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348.
349. {* The dst_mask is what parts of the instruction are replaced
350. into the instruction. In most cases src_mask == dst_mask,
351. except in the above special case, where dst_mask would be
352. 0x000000ff, and src_mask would be 0x00000000. *}
65cab589 353. bfd_vma dst_mask;
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354.
355. {* When some formats create PC relative instructions, they leave
356. the value of the pc of the place being relocated in the offset
357. slot of the instruction, so that a PC relative relocation can
65cab589 358. be made just by adding in an ordinary offset (e.g., sun3 a.out).
e98e6ec1 359. Some formats leave the displacement part of an instruction
65cab589 360. empty (e.g., m88k bcs), this flag signals the fact.*}
0cda46cf 361. boolean pcrel_offset;
e98e6ec1 362.
0cda46cf 363.} reloc_howto_type;
985fca12 364
0cda46cf 365*/
985fca12 366
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367/*
368FUNCTION
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369 the HOWTO macro
370
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371DESCRIPTION
372 The HOWTO define is horrible and will go away.
373
374
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375.#define HOWTO(C, R,S,B, P, BI, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
376. {(unsigned)C,R,S,B, P, BI, O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
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377
378DESCRIPTION
379 And will be replaced with the totally magic way. But for the
380 moment, we are compatible, so do it this way..
381
382
66a277ab 383.#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,complain_overflow_dont,FUNCTION, NAME,false,0,0,IN)
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384.
385DESCRIPTION
386 Helper routine to turn a symbol into a relocation value.
387
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388.#define HOWTO_PREPARE(relocation, symbol) \
389. { \
390. if (symbol != (asymbol *)NULL) { \
65cab589 391. if (bfd_is_com_section (symbol->section)) { \
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392. relocation = 0; \
393. } \
394. else { \
395. relocation = symbol->value; \
396. } \
397. } \
398.}
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399
400*/
401
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402/*
403TYPEDEF
404 reloc_chain
985fca12 405
0cda46cf 406DESCRIPTION
985fca12 407
0cda46cf 408 How relocs are tied together
985fca12 409
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410.typedef unsigned char bfd_byte;
411.
412.typedef struct relent_chain {
413. arelent relent;
414. struct relent_chain *next;
415.} arelent_chain;
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416
417*/
418
419
420
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421/*
422FUNCTION
423 bfd_perform_relocation
424
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425SYNOPSIS
426 bfd_reloc_status_type
427 bfd_perform_relocation
428 (bfd * abfd,
429 arelent *reloc_entry,
430 PTR data,
431 asection *input_section,
432 bfd *output_bfd);
433
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434DESCRIPTION
435 If an output_bfd is supplied to this function the generated
436 image will be relocatable, the relocations are copied to the
437 output file after they have been changed to reflect the new
438 state of the world. There are two ways of reflecting the
439 results of partial linkage in an output file; by modifying the
440 output data in place, and by modifying the relocation record.
65cab589 441 Some native formats (e.g., basic a.out and basic coff) have no
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442 way of specifying an addend in the relocation type, so the
443 addend has to go in the output data. This is no big deal
444 since in these formats the output data slot will always be big
445 enough for the addend. Complex reloc types with addends were
446 invented to solve just this problem.
447
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448*/
449
450
0cda46cf 451bfd_reloc_status_type
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452DEFUN(bfd_perform_relocation,(abfd,
453 reloc_entry,
454 data,
455 input_section,
456 output_bfd),
457 bfd *abfd AND
458 arelent *reloc_entry AND
459 PTR data AND
460 asection *input_section AND
461 bfd *output_bfd)
462{
463 bfd_vma relocation;
0cda46cf 464 bfd_reloc_status_type flag = bfd_reloc_ok;
65cab589 465 bfd_size_type addr = reloc_entry->address ;
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466 bfd_vma output_base = 0;
467 reloc_howto_type *howto = reloc_entry->howto;
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468 asection *reloc_target_output_section ;
469
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470 asymbol *symbol;
471
e98e6ec1 472 symbol = *( reloc_entry->sym_ptr_ptr);
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473 if ((symbol->section == &bfd_abs_section)
474 && output_bfd != (bfd *)NULL)
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475 {
476 reloc_entry->address += input_section->output_offset;
477 return bfd_reloc_ok;
478 }
479
480 if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL)
5022aea5 481 flag = bfd_reloc_undefined;
985fca12 482
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483 /* If there is a function supplied to handle this relocation type,
484 call it. It'll return `bfd_reloc_continue' if further processing
485 can be done. */
486 if (howto->special_function)
487 {
488 bfd_reloc_status_type cont;
489 cont = howto->special_function (abfd, reloc_entry, symbol, data,
490 input_section, output_bfd);
491 if (cont != bfd_reloc_continue)
492 return cont;
493 }
985fca12 494
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495 /* Is the address of the relocation really within the section? */
496 if (reloc_entry->address > input_section->_cooked_size)
497 return bfd_reloc_outofrange;
985fca12 498
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499 /* Work out which section the relocation is targetted at and the
500 initial relocation command value. */
501
502 /* Get symbol value. (Common symbols are special.) */
503 if (bfd_is_com_section (symbol->section))
5022aea5 504 relocation = 0;
58acdbd7 505 else
5022aea5 506 relocation = symbol->value;
985fca12 507
985fca12 508
e98e6ec1 509 reloc_target_output_section = symbol->section->output_section;
985fca12 510
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511 /* Convert input-section-relative symbol value to absolute. */
512 if (output_bfd && howto->partial_inplace==false)
5022aea5 513 output_base = 0;
58acdbd7 514 else
5022aea5 515 output_base = reloc_target_output_section->vma;
985fca12 516
65cab589 517 relocation += output_base + symbol->section->output_offset;
985fca12 518
58acdbd7 519 /* Add in supplied addend. */
65cab589 520 relocation += reloc_entry->addend;
985fca12 521
985fca12 522 if (howto->pc_relative == true)
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523 {
524 /* Anything which started out as pc relative should end up that
525 way too.
985fca12 526
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527 There are two ways we can see a pcrel instruction. Sometimes
528 the pcrel displacement has been partially calculated, it
529 includes the distance from the start of the section to the
530 instruction in it (e.g., sun3), and sometimes the field is
531 totally blank - e.g., m88kbcs. */
985fca12 532
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533 relocation -=
534 input_section->output_section->vma + input_section->output_offset;
535
536 if (howto->pcrel_offset == true)
537 relocation -= reloc_entry->address;
5022aea5 538 }
e98e6ec1 539
c26d7d17 540 if (output_bfd!= (bfd *)NULL)
5022aea5 541 {
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542 if ( howto->partial_inplace == false)
543 {
544 /* This is a partial relocation, and we want to apply the relocation
545 to the reloc entry rather than the raw data. Modify the reloc
546 inplace to reflect what we now know. */
547 reloc_entry->addend = relocation;
548 reloc_entry->address += input_section->output_offset;
549 return flag;
550 }
c26d7d17 551 else
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552 {
553 /* This is a partial relocation, but inplace, so modify the
554 reloc record a bit.
555
556 If we've relocated with a symbol with a section, change
557 into a ref to the section belonging to the symbol. */
558
559 reloc_entry->address += input_section->output_offset;
560
561 /* WTF?? */
562 if (abfd->xvec->flavour == bfd_target_coff_flavour)
563 {
564 relocation -= reloc_entry->addend;
565 reloc_entry->addend = 0;
566 }
567 else
568 {
569 reloc_entry->addend = relocation;
570 }
571 }
985fca12 572 }
e98e6ec1 573 else
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574 {
575 reloc_entry->addend = 0;
576 }
985fca12 577
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578 /* FIXME: This overflow checking is incomplete, because the value
579 might have overflowed before we get here. For a correct check we
580 need to compute the value in a size larger than bitsize, but we
581 can't reasonably do that for a reloc the same size as a host
a49880c8
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582 machine word.
583 FIXME: We should also do overflow checking on the result after
584 adding in the value contained in the object file. */
109a640b 585 if (howto->complain_on_overflow != complain_overflow_dont)
65cab589 586 {
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587 bfd_vma check;
588
589 /* Get the value that will be used for the relocation, but
590 starting at bit position zero. */
591 if (howto->rightshift > howto->bitpos)
592 check = relocation >> (howto->rightshift - howto->bitpos);
593 else
594 check = relocation << (howto->bitpos - howto->rightshift);
595 switch (howto->complain_on_overflow)
596 {
597 case complain_overflow_signed:
598 {
599 /* Assumes two's complement. */
600 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
601 bfd_signed_vma reloc_signed_min = ~ reloc_signed_max;
602
603 /* The above right shift is incorrect for a signed value.
604 Fix it up by forcing on the upper bits. */
605 if (howto->rightshift > howto->bitpos
606 && (bfd_signed_vma) relocation < 0)
607 check |= ((bfd_vma) -1
608 &~ ((bfd_vma) -1
609 >> (howto->rightshift - howto->bitpos)));
610 if ((bfd_signed_vma) check > reloc_signed_max
611 || (bfd_signed_vma) check < reloc_signed_min)
612 flag = bfd_reloc_overflow;
613 }
614 break;
615 case complain_overflow_unsigned:
616 {
617 /* Assumes two's complement. This expression avoids
618 overflow if howto->bitsize is the number of bits in
619 bfd_vma. */
620 bfd_vma reloc_unsigned_max =
621 (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
622
623 if ((bfd_vma) check > reloc_unsigned_max)
624 flag = bfd_reloc_overflow;
625 }
626 break;
627 case complain_overflow_bitfield:
628 {
629 /* Assumes two's complement. This expression avoids
630 overflow if howto->bitsize is the number of bits in
631 bfd_vma. */
632 bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
633
634 if (((bfd_vma) check &~ reloc_bits) != 0
635 && ((bfd_vma) check &~ reloc_bits) != (-1 &~ reloc_bits))
a49880c8
KR
636 {
637 /* The above right shift is incorrect for a signed
638 value. See if turning on the upper bits fixes the
639 overflow. */
640 if (howto->rightshift > howto->bitpos
641 && (bfd_signed_vma) relocation < 0)
642 {
643 check |= ((bfd_vma) -1
644 &~ ((bfd_vma) -1
645 >> (howto->rightshift - howto->bitpos)));
646 if (((bfd_vma) check &~ reloc_bits) != (-1 &~ reloc_bits))
647 flag = bfd_reloc_overflow;
648 }
649 else
650 flag = bfd_reloc_overflow;
651 }
109a640b
KR
652 }
653 break;
654 default:
655 abort ();
656 }
65cab589
DM
657 }
658
985fca12
SC
659 /*
660 Either we are relocating all the way, or we don't want to apply
661 the relocation to the reloc entry (probably because there isn't
662 any room in the output format to describe addends to relocs)
663 */
664 relocation >>= howto->rightshift;
665
666 /* Shift everything up to where it's going to be used */
667
668 relocation <<= howto->bitpos;
669
670 /* Wait for the day when all have the mask in them */
671
672 /* What we do:
673 i instruction to be left alone
674 o offset within instruction
675 r relocation offset to apply
676 S src mask
677 D dst mask
678 N ~dst mask
679 A part 1
680 B part 2
681 R result
682
683 Do this:
684 i i i i i o o o o o from bfd_get<size>
685 and S S S S S to get the size offset we want
686 + r r r r r r r r r r to get the final value to place
687 and D D D D D to chop to right size
688 -----------------------
689 A A A A A
690 And this:
691 ... i i i i i o o o o o from bfd_get<size>
692 and N N N N N get instruction
693 -----------------------
694 ... B B B B B
695
696 And then:
697 B B B B B
698 or A A A A A
699 -----------------------
700 R R R R R R R R R R put into bfd_put<size>
701 */
702
703#define DOIT(x) \
704 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
705
e98e6ec1 706 switch (howto->size)
65cab589
DM
707 {
708 case 0:
709 {
710 char x = bfd_get_8(abfd, (char *)data + addr);
711 DOIT(x);
712 bfd_put_8(abfd,x, (unsigned char *) data + addr);
713 }
714 break;
715
716 case 1:
717 if (relocation)
718 {
719 short x = bfd_get_16(abfd, (bfd_byte *)data + addr);
720 DOIT(x);
721 bfd_put_16(abfd, x, (unsigned char *)data + addr);
722 }
723 break;
724 case 2:
725 if (relocation)
726 {
727 long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
728 DOIT (x);
729 bfd_put_32 (abfd, x, (bfd_byte *)data + addr);
730 }
731 break;
732 case -2:
733 {
734 long x = bfd_get_32(abfd, (bfd_byte *) data + addr);
735 relocation = -relocation;
736 DOIT(x);
737 bfd_put_32(abfd,x, (bfd_byte *)data + addr);
738 }
739 break;
740
741 case 3:
65cab589
DM
742 /* Do nothing */
743 break;
109a640b
KR
744
745 case 4:
746#ifdef BFD64
747 if (relocation)
748 {
749 bfd_vma x = bfd_get_64 (abfd, (bfd_byte *) data + addr);
750 DOIT (x);
751 bfd_put_64 (abfd, x, (bfd_byte *) data + addr);
752 }
753#else
754 abort ();
755#endif
756 break;
65cab589
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757 default:
758 return bfd_reloc_other;
759 }
985fca12
SC
760
761 return flag;
762}
c618de01
SC
763
764
2cf44d7b 765
0cda46cf 766/*
c26d7d17 767DOCDD
e98e6ec1
SC
768INODE
769 howto manager, , typedef arelent, Relocations
770
0cda46cf
SC
771SECTION
772 The howto manager
2cf44d7b 773
0cda46cf
SC
774 When an application wants to create a relocation, but doesn't
775 know what the target machine might call it, it can find out by
776 using this bit of code.
2cf44d7b 777
0cda46cf 778*/
2cf44d7b 779
0cda46cf
SC
780/*
781TYPEDEF
782 bfd_reloc_code_type
2cf44d7b 783
0cda46cf
SC
784DESCRIPTION
785 The insides of a reloc code
786
e98e6ec1
SC
787CODE_FRAGMENT
788.
789.typedef enum bfd_reloc_code_real
c26d7d17 790.
e98e6ec1 791.{
defcfb55
KR
792. {* 64 bits wide, simple reloc *}
793. BFD_RELOC_64,
794. {* 64 bits, PC-relative *}
795. BFD_RELOC_64_PCREL,
796.
797. {* 32 bits wide, simple reloc *}
798. BFD_RELOC_32,
799. {* 32 bits, PC-relative *}
800. BFD_RELOC_32_PCREL,
801.
e98e6ec1
SC
802. {* 16 bits wide, simple reloc *}
803. BFD_RELOC_16,
defcfb55
KR
804. {* 16 bits, PC-relative *}
805. BFD_RELOC_16_PCREL,
e98e6ec1
SC
806.
807. {* 8 bits wide, simple *}
0cda46cf 808. BFD_RELOC_8,
e98e6ec1 809. {* 8 bits wide, pc relative *}
0cda46cf 810. BFD_RELOC_8_PCREL,
defcfb55
KR
811. {* 8 bits wide, but used to form an address like 0xffnn *}
812. BFD_RELOC_8_FFnn,
e98e6ec1
SC
813.
814. {* The type of reloc used to build a contructor table - at the
815. moment probably a 32 bit wide abs address, but the cpu can
816. choose. *}
817.
8070f29d
KR
818. BFD_RELOC_CTOR,
819.
8070f29d
KR
820. {* High 22 bits of 32-bit value; simple reloc. *}
821. BFD_RELOC_HI22,
822. {* Low 10 bits. *}
823. BFD_RELOC_LO10,
824.
825. {* Reloc types used for i960/b.out. *}
826. BFD_RELOC_24_PCREL,
827. BFD_RELOC_I960_CALLJ,
828.
8070f29d
KR
829. {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
830. word displacement, e.g. for SPARC) *}
831. BFD_RELOC_32_PCREL_S2,
832.
833. {* now for the sparc/elf codes *}
834. BFD_RELOC_NONE, {* actually used *}
835. BFD_RELOC_SPARC_WDISP22,
836. BFD_RELOC_SPARC22,
837. BFD_RELOC_SPARC13,
8070f29d
KR
838. BFD_RELOC_SPARC_GOT10,
839. BFD_RELOC_SPARC_GOT13,
840. BFD_RELOC_SPARC_GOT22,
841. BFD_RELOC_SPARC_PC10,
842. BFD_RELOC_SPARC_PC22,
843. BFD_RELOC_SPARC_WPLT30,
844. BFD_RELOC_SPARC_COPY,
845. BFD_RELOC_SPARC_GLOB_DAT,
846. BFD_RELOC_SPARC_JMP_SLOT,
847. BFD_RELOC_SPARC_RELATIVE,
848. BFD_RELOC_SPARC_UA32,
849.
850. {* this one is a.out specific? *}
58acdbd7 851. BFD_RELOC_SPARC_BASE13,
8070f29d
KR
852. BFD_RELOC_SPARC_BASE22,
853.
defcfb55 854. {* start-sanitize-v9 *}
defcfb55
KR
855. BFD_RELOC_SPARC_10,
856. BFD_RELOC_SPARC_11,
857.#define BFD_RELOC_SPARC_64 BFD_RELOC_64
858. BFD_RELOC_SPARC_OLO10,
859. BFD_RELOC_SPARC_HH22,
860. BFD_RELOC_SPARC_HM10,
861. BFD_RELOC_SPARC_LM22,
862. BFD_RELOC_SPARC_PC_HH22,
863. BFD_RELOC_SPARC_PC_HM10,
864. BFD_RELOC_SPARC_PC_LM22,
865. BFD_RELOC_SPARC_WDISP16,
58acdbd7 866. BFD_RELOC_SPARC_WDISP19,
defcfb55
KR
867. BFD_RELOC_SPARC_GLOB_JMP,
868. BFD_RELOC_SPARC_LO7,
869. {* end-sanitize-v9 *}
58acdbd7 870.
65cab589
DM
871. {* Bits 27..2 of the relocation address shifted right 2 bits;
872. simple reloc otherwise. *}
873. BFD_RELOC_MIPS_JMP,
874.
875. {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
876. BFD_RELOC_16_PCREL_S2,
877.
878. {* High 16 bits of 32-bit value; simple reloc. *}
879. BFD_RELOC_HI16,
880. {* High 16 bits of 32-bit value but the low 16 bits will be sign
881. extended and added to form the final result. If the low 16
882. bits form a negative number, we need to add one to the high value
883. to compensate for the borrow when the low bits are added. *}
884. BFD_RELOC_HI16_S,
885. {* Low 16 bits. *}
886. BFD_RELOC_LO16,
887.
888. {* 16 bit relocation relative to the global pointer. *}
889. BFD_RELOC_MIPS_GPREL,
890.
891. {* These are, so far, specific to HPPA processors. I'm not sure that
892. some don't duplicate other reloc types, such as BFD_RELOC_32 and
893. _32_PCREL. Also, many more were in the list I got that don't
894. fit in well in the model BFD uses, so I've omitted them for now.
895. If we do make this reloc type get used for code that really does
896. implement the funky reloc types, they'll have to be added to this
897. list. *}
898. BFD_RELOC_HPPA_32,
899. BFD_RELOC_HPPA_11,
900. BFD_RELOC_HPPA_14,
901. BFD_RELOC_HPPA_17,
902. BFD_RELOC_HPPA_L21,
903. BFD_RELOC_HPPA_R11,
904. BFD_RELOC_HPPA_R14,
905. BFD_RELOC_HPPA_R17,
906. BFD_RELOC_HPPA_LS21,
907. BFD_RELOC_HPPA_RS11,
908. BFD_RELOC_HPPA_RS14,
909. BFD_RELOC_HPPA_RS17,
910. BFD_RELOC_HPPA_LD21,
911. BFD_RELOC_HPPA_RD11,
912. BFD_RELOC_HPPA_RD14,
913. BFD_RELOC_HPPA_RD17,
914. BFD_RELOC_HPPA_LR21,
915. BFD_RELOC_HPPA_RR14,
916. BFD_RELOC_HPPA_RR17,
917. BFD_RELOC_HPPA_GOTOFF_11,
918. BFD_RELOC_HPPA_GOTOFF_14,
919. BFD_RELOC_HPPA_GOTOFF_L21,
920. BFD_RELOC_HPPA_GOTOFF_R11,
921. BFD_RELOC_HPPA_GOTOFF_R14,
922. BFD_RELOC_HPPA_GOTOFF_LS21,
923. BFD_RELOC_HPPA_GOTOFF_RS11,
924. BFD_RELOC_HPPA_GOTOFF_RS14,
925. BFD_RELOC_HPPA_GOTOFF_LD21,
926. BFD_RELOC_HPPA_GOTOFF_RD11,
927. BFD_RELOC_HPPA_GOTOFF_RD14,
928. BFD_RELOC_HPPA_GOTOFF_LR21,
929. BFD_RELOC_HPPA_GOTOFF_RR14,
930. BFD_RELOC_HPPA_DLT_32,
931. BFD_RELOC_HPPA_DLT_11,
932. BFD_RELOC_HPPA_DLT_14,
933. BFD_RELOC_HPPA_DLT_L21,
934. BFD_RELOC_HPPA_DLT_R11,
935. BFD_RELOC_HPPA_DLT_R14,
936. BFD_RELOC_HPPA_ABS_CALL_11,
937. BFD_RELOC_HPPA_ABS_CALL_14,
938. BFD_RELOC_HPPA_ABS_CALL_17,
939. BFD_RELOC_HPPA_ABS_CALL_L21,
940. BFD_RELOC_HPPA_ABS_CALL_R11,
941. BFD_RELOC_HPPA_ABS_CALL_R14,
942. BFD_RELOC_HPPA_ABS_CALL_R17,
943. BFD_RELOC_HPPA_ABS_CALL_LS21,
944. BFD_RELOC_HPPA_ABS_CALL_RS11,
945. BFD_RELOC_HPPA_ABS_CALL_RS14,
946. BFD_RELOC_HPPA_ABS_CALL_RS17,
947. BFD_RELOC_HPPA_ABS_CALL_LD21,
948. BFD_RELOC_HPPA_ABS_CALL_RD11,
949. BFD_RELOC_HPPA_ABS_CALL_RD14,
950. BFD_RELOC_HPPA_ABS_CALL_RD17,
951. BFD_RELOC_HPPA_ABS_CALL_LR21,
952. BFD_RELOC_HPPA_ABS_CALL_RR14,
953. BFD_RELOC_HPPA_ABS_CALL_RR17,
954. BFD_RELOC_HPPA_PCREL_CALL_11,
955. BFD_RELOC_HPPA_PCREL_CALL_12,
956. BFD_RELOC_HPPA_PCREL_CALL_14,
957. BFD_RELOC_HPPA_PCREL_CALL_17,
958. BFD_RELOC_HPPA_PCREL_CALL_L21,
959. BFD_RELOC_HPPA_PCREL_CALL_R11,
960. BFD_RELOC_HPPA_PCREL_CALL_R14,
961. BFD_RELOC_HPPA_PCREL_CALL_R17,
962. BFD_RELOC_HPPA_PCREL_CALL_LS21,
963. BFD_RELOC_HPPA_PCREL_CALL_RS11,
964. BFD_RELOC_HPPA_PCREL_CALL_RS14,
965. BFD_RELOC_HPPA_PCREL_CALL_RS17,
966. BFD_RELOC_HPPA_PCREL_CALL_LD21,
967. BFD_RELOC_HPPA_PCREL_CALL_RD11,
968. BFD_RELOC_HPPA_PCREL_CALL_RD14,
969. BFD_RELOC_HPPA_PCREL_CALL_RD17,
970. BFD_RELOC_HPPA_PCREL_CALL_LR21,
971. BFD_RELOC_HPPA_PCREL_CALL_RR14,
972. BFD_RELOC_HPPA_PCREL_CALL_RR17,
973. BFD_RELOC_HPPA_PLABEL_32,
974. BFD_RELOC_HPPA_PLABEL_11,
975. BFD_RELOC_HPPA_PLABEL_14,
976. BFD_RELOC_HPPA_PLABEL_L21,
977. BFD_RELOC_HPPA_PLABEL_R11,
978. BFD_RELOC_HPPA_PLABEL_R14,
979. BFD_RELOC_HPPA_UNWIND_ENTRY,
980. BFD_RELOC_HPPA_UNWIND_ENTRIES,
981.
a49880c8
KR
982. {* i386/elf relocations *}
983. BFD_RELOC_386_GOT32,
984. BFD_RELOC_386_PLT32,
985. BFD_RELOC_386_COPY,
986. BFD_RELOC_386_GLOB_DAT,
987. BFD_RELOC_386_JUMP_SLOT,
988. BFD_RELOC_386_RELATIVE,
989. BFD_RELOC_386_GOTOFF,
990. BFD_RELOC_386_GOTPC,
991.
8070f29d
KR
992. {* this must be the highest numeric value *}
993. BFD_RELOC_UNUSED
0cda46cf 994. } bfd_reloc_code_real_type;
2cf44d7b
SC
995*/
996
997
998
0cda46cf
SC
999/*
1000SECTION
1001 bfd_reloc_type_lookup
2cf44d7b 1002
e98e6ec1
SC
1003SYNOPSIS
1004 CONST struct reloc_howto_struct *
3860075f 1005 bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
e98e6ec1 1006
0cda46cf
SC
1007DESCRIPTION
1008 This routine returns a pointer to a howto struct which when
1009 invoked, will perform the supplied relocation on data from the
1010 architecture noted.
2cf44d7b 1011
2cf44d7b
SC
1012*/
1013
1014
1015CONST struct reloc_howto_struct *
3860075f 1016DEFUN(bfd_reloc_type_lookup,(abfd, code),
8070f29d 1017 bfd *abfd AND
3860075f 1018 bfd_reloc_code_real_type code)
2cf44d7b 1019{
8070f29d 1020 return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
2cf44d7b
SC
1021}
1022
0cda46cf 1023static reloc_howto_type bfd_howto_32 =
66a277ab 1024 HOWTO(0, 00,2,32,false,0,complain_overflow_bitfield,0,"VRT32", false,0xffffffff,0xffffffff,true);
2cf44d7b
SC
1025
1026
0cda46cf 1027/*
e98e6ec1 1028INTERNAL_FUNCTION
0cda46cf
SC
1029 bfd_default_reloc_type_lookup
1030
0cda46cf
SC
1031SYNOPSIS
1032 CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
65cab589 1033 (bfd *abfd AND
3860075f 1034 bfd_reloc_code_real_type code);
0cda46cf 1035
e98e6ec1 1036DESCRIPTION
65cab589 1037 Provides a default relocation lookup routine for any architecture.
e98e6ec1
SC
1038
1039
0cda46cf 1040*/
65cab589 1041
0cda46cf 1042CONST struct reloc_howto_struct *
65cab589
DM
1043DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
1044 bfd *abfd AND
1045 bfd_reloc_code_real_type code)
0cda46cf 1046{
65cab589 1047 switch (code)
0cda46cf 1048 {
65cab589
DM
1049 case BFD_RELOC_CTOR:
1050 /* The type of reloc used in a ctor, which will be as wide as the
1051 address - so either a 64, 32, or 16 bitter.. */
1052 switch (bfd_get_arch_info (abfd)->bits_per_address) {
1053 case 64:
1054 BFD_FAIL();
1055 case 32:
1056 return &bfd_howto_32;
1057 case 16:
1058 BFD_FAIL();
1059 default:
0cda46cf 1060 BFD_FAIL();
65cab589
DM
1061 }
1062 default:
1063 BFD_FAIL();
0cda46cf 1064 }
65cab589 1065 return (CONST struct reloc_howto_struct *)NULL;
0cda46cf 1066}
e98e6ec1
SC
1067
1068
d58b7049
SC
1069/*
1070INTERNAL_FUNCTION
1071 bfd_generic_relax_section
1072
1073SYNOPSIS
1074 boolean bfd_generic_relax_section
1075 (bfd *abfd,
1076 asection *section,
5022aea5 1077 asymbol **symbols);
d58b7049
SC
1078
1079DESCRIPTION
1080 Provides default handling for relaxing for back ends which
8070f29d 1081 don't do relaxing -- i.e., does nothing.
d58b7049
SC
1082*/
1083
1084boolean
5022aea5 1085DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
d58b7049
SC
1086 bfd *abfd AND
1087 asection *section AND
5022aea5 1088 asymbol **symbols)
d58b7049
SC
1089{
1090
1091 return false;
1092
1093}
e98e6ec1 1094
d58b7049 1095
e98e6ec1
SC
1096/*
1097INTERNAL_FUNCTION
1098 bfd_generic_get_relocated_section_contents
1099
1100SYNOPSIS
1101 bfd_byte *
65cab589
DM
1102 bfd_generic_get_relocated_section_contents (bfd *abfd,
1103 struct bfd_seclet *seclet,
1104 bfd_byte *data,
1105 boolean relocateable);
e98e6ec1
SC
1106
1107DESCRIPTION
1108 Provides default handling of relocation effort for back ends
1109 which can't be bothered to do it efficiently.
1110
1111*/
1112
1113bfd_byte *
65cab589
DM
1114DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
1115 seclet,
1116 data,
1117 relocateable),
e98e6ec1 1118 bfd *abfd AND
65cab589
DM
1119 struct bfd_seclet *seclet AND
1120 bfd_byte *data AND
1121 boolean relocateable)
e98e6ec1
SC
1122{
1123 extern bfd_error_vector_type bfd_error_vector;
e98e6ec1
SC
1124
1125 /* Get enough memory to hold the stuff */
1126 bfd *input_bfd = seclet->u.indirect.section->owner;
1127 asection *input_section = seclet->u.indirect.section;
1128
8070f29d 1129
e98e6ec1 1130
defcfb55 1131 size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
8070f29d 1132 arelent **reloc_vector = (arelent **) alloca(reloc_size);
e98e6ec1
SC
1133
1134 /* read in the section */
1135 bfd_get_section_contents(input_bfd,
1136 input_section,
1137 data,
1138 0,
1139 input_section->_raw_size);
1140
1141/* We're not relaxing the section, so just copy the size info */
1142 input_section->_cooked_size = input_section->_raw_size;
1143 input_section->reloc_done = true;
1144
1145
1146 if (bfd_canonicalize_reloc(input_bfd,
1147 input_section,
1148 reloc_vector,
1149 seclet->u.indirect.symbols) )
1150 {
1151 arelent **parent;
1152 for (parent = reloc_vector; * parent != (arelent *)NULL;
1153 parent++)
1154 {
1155 bfd_reloc_status_type r=
1156 bfd_perform_relocation(input_bfd,
1157 *parent,
1158 data,
65cab589
DM
1159 input_section,
1160 relocateable ? abfd : (bfd *) NULL);
e98e6ec1 1161
65cab589
DM
1162 if (relocateable)
1163 {
1164 asection *os = input_section->output_section;
1165
1166 /* A partial link, so keep the relocs */
1167 os->orelocation[os->reloc_count] = *parent;
1168 os->reloc_count++;
1169 }
e98e6ec1
SC
1170
1171 if (r != bfd_reloc_ok)
1172 {
e98e6ec1
SC
1173 switch (r)
1174 {
1175 case bfd_reloc_undefined:
1176 bfd_error_vector.undefined_symbol(*parent, seclet);
1177 break;
1178 case bfd_reloc_dangerous:
1179 bfd_error_vector.reloc_dangerous(*parent, seclet);
1180 break;
1181 case bfd_reloc_outofrange:
1182 case bfd_reloc_overflow:
1183 bfd_error_vector.reloc_value_truncated(*parent, seclet);
1184 break;
1185 default:
1186 abort();
1187 break;
1188 }
1189
1190 }
1191 }
1192 }
1193
8070f29d 1194
e98e6ec1
SC
1195 return data;
1196
1197
1198}
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