New file bfdsumm.texi to share with ld.
[deliverable/binutils-gdb.git] / bfd / reloc.c
CommitLineData
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
245
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246/*
247SUBSUBSECTION
e98e6ec1 248 <<reloc_howto_type>>
985fca12 249
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250 The <<reloc_howto_type>> is a structure which contains all the
251 information that BFD needs to know to tie up a back end's data.
985fca12 252
e98e6ec1 253CODE_FRAGMENT
5022aea5 254.struct symbol_cache_entry; {* Forward declaration *}
e98e6ec1 255.
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256.typedef CONST struct reloc_howto_struct
257.{
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258. {* The type field has mainly a documetary use - the back end can
259. to what it wants with it, though the normally the back end's
260. external idea of what a reloc number would be would be stored
261. in this field. For example, the a PC relative word relocation
262. in a coff environment would have the type 023 - because that's
263. what the outside world calls a R_PCRWORD reloc. *}
0cda46cf 264. unsigned int type;
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265.
266. {* The value the final relocation is shifted right by. This drops
267. unwanted data from the relocation. *}
0cda46cf 268. unsigned int rightshift;
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269.
270. {* The size of the item to be relocated - 0, is one byte, 1 is 2
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271. bytes, 2 is four bytes. A negative value indicates that the
272. result is to be subtracted from the data. *}
c26d7d17 273. int size;
e98e6ec1 274.
65cab589 275. {* Now obsolete? But m68k-coff still uses it... *}
0cda46cf 276. unsigned int bitsize;
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277.
278. {* Notes that the relocation is relative to the location in the
279. data section of the addend. The relocation function will
280. subtract from the relocation value the address of the location
281. being relocated. *}
0cda46cf 282. boolean pc_relative;
e98e6ec1 283.
0cda46cf 284. unsigned int bitpos;
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285.
286. {* Now obsolete *}
0cda46cf 287. boolean absolute;
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288.
289. {* Causes the relocation routine to return an error if overflow
290. is detected when relocating. *}
0cda46cf 291. boolean complain_on_overflow;
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292.
293. {* If this field is non null, then the supplied function is
294. called rather than the normal function. This allows really
65cab589 295. strange relocation methods to be accomodated (e.g., i960 callj
e98e6ec1 296. instructions). *}
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297. bfd_reloc_status_type (*special_function)
298. PARAMS ((bfd *abfd,
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299. arelent *reloc_entry,
300. struct symbol_cache_entry *symbol,
301. PTR data,
8070f29d 302. asection *input_section,
fefb4b30 303. bfd *output_bfd));
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304.
305. {* The textual name of the relocation type. *}
0cda46cf 306. char *name;
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307.
308. {* When performing a partial link, some formats must modify the
309. relocations rather than the data - this flag signals this.*}
0cda46cf 310. boolean partial_inplace;
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311.
312. {* The src_mask is used to select what parts of the read in data
65cab589 313. are to be used in the relocation sum. E.g., if this was an 8 bit
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314. bit of data which we read and relocated, this would be
315. 0x000000ff. When we have relocs which have an addend, such as
316. sun4 extended relocs, the value in the offset part of a
317. relocating field is garbage so we never use it. In this case
318. the mask would be 0x00000000. *}
65cab589 319. bfd_vma src_mask;
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320.
321. {* The dst_mask is what parts of the instruction are replaced
322. into the instruction. In most cases src_mask == dst_mask,
323. except in the above special case, where dst_mask would be
324. 0x000000ff, and src_mask would be 0x00000000. *}
65cab589 325. bfd_vma dst_mask;
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326.
327. {* When some formats create PC relative instructions, they leave
328. the value of the pc of the place being relocated in the offset
329. slot of the instruction, so that a PC relative relocation can
65cab589 330. be made just by adding in an ordinary offset (e.g., sun3 a.out).
e98e6ec1 331. Some formats leave the displacement part of an instruction
65cab589 332. empty (e.g., m88k bcs), this flag signals the fact.*}
0cda46cf 333. boolean pcrel_offset;
e98e6ec1 334.
0cda46cf 335.} reloc_howto_type;
985fca12 336
0cda46cf 337*/
985fca12 338
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339/*
340FUNCTION
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341 the HOWTO macro
342
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343DESCRIPTION
344 The HOWTO define is horrible and will go away.
345
346
347.#define HOWTO(C, R,S,B, P, BI, ABS, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \
348. {(unsigned)C,R,S,B, P, BI, ABS,O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC}
349
350DESCRIPTION
351 And will be replaced with the totally magic way. But for the
352 moment, we are compatible, so do it this way..
353
354
355.#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,false,false,FUNCTION, NAME,false,0,0,IN)
356.
357DESCRIPTION
358 Helper routine to turn a symbol into a relocation value.
359
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360.#define HOWTO_PREPARE(relocation, symbol) \
361. { \
362. if (symbol != (asymbol *)NULL) { \
65cab589 363. if (bfd_is_com_section (symbol->section)) { \
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364. relocation = 0; \
365. } \
366. else { \
367. relocation = symbol->value; \
368. } \
369. } \
370.}
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371
372*/
373
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374/*
375TYPEDEF
376 reloc_chain
985fca12 377
0cda46cf 378DESCRIPTION
985fca12 379
0cda46cf 380 How relocs are tied together
985fca12 381
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382.typedef unsigned char bfd_byte;
383.
384.typedef struct relent_chain {
385. arelent relent;
386. struct relent_chain *next;
387.} arelent_chain;
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388
389*/
390
391
392
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393/*
394FUNCTION
395 bfd_perform_relocation
396
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397SYNOPSIS
398 bfd_reloc_status_type
399 bfd_perform_relocation
400 (bfd * abfd,
401 arelent *reloc_entry,
402 PTR data,
403 asection *input_section,
404 bfd *output_bfd);
405
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406DESCRIPTION
407 If an output_bfd is supplied to this function the generated
408 image will be relocatable, the relocations are copied to the
409 output file after they have been changed to reflect the new
410 state of the world. There are two ways of reflecting the
411 results of partial linkage in an output file; by modifying the
412 output data in place, and by modifying the relocation record.
65cab589 413 Some native formats (e.g., basic a.out and basic coff) have no
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414 way of specifying an addend in the relocation type, so the
415 addend has to go in the output data. This is no big deal
416 since in these formats the output data slot will always be big
417 enough for the addend. Complex reloc types with addends were
418 invented to solve just this problem.
419
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420*/
421
422
0cda46cf 423bfd_reloc_status_type
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424DEFUN(bfd_perform_relocation,(abfd,
425 reloc_entry,
426 data,
427 input_section,
428 output_bfd),
429 bfd *abfd AND
430 arelent *reloc_entry AND
431 PTR data AND
432 asection *input_section AND
433 bfd *output_bfd)
434{
435 bfd_vma relocation;
0cda46cf 436 bfd_reloc_status_type flag = bfd_reloc_ok;
65cab589 437 bfd_size_type addr = reloc_entry->address ;
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438 bfd_vma output_base = 0;
439 reloc_howto_type *howto = reloc_entry->howto;
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440 asection *reloc_target_output_section ;
441
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442 asymbol *symbol;
443
e98e6ec1 444 symbol = *( reloc_entry->sym_ptr_ptr);
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445 if ((symbol->section == &bfd_abs_section)
446 && output_bfd != (bfd *)NULL)
447 {
448 reloc_entry->address += input_section->output_offset;
449
450 return bfd_reloc_ok;
451
452 }
453
e98e6ec1 454 if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL) {
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455 flag = bfd_reloc_undefined;
456 }
985fca12 457
8070f29d 458 if (howto->special_function) {
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459 bfd_reloc_status_type cont;
460 cont = howto->special_function(abfd,
461 reloc_entry,
462 symbol,
463 data,
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464 input_section,
465 output_bfd);
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466 if (cont != bfd_reloc_continue) return cont;
467 }
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468
469 /*
470 Work out which section the relocation is targetted at and the
471 initial relocation command value.
472 */
473
474
65cab589 475 if (bfd_is_com_section (symbol->section)) {
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476 relocation = 0;
477 }
e98e6ec1 478 else {
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479 relocation = symbol->value;
480 }
985fca12 481
985fca12 482
e98e6ec1 483 reloc_target_output_section = symbol->section->output_section;
985fca12 484
e98e6ec1 485 if (output_bfd && howto->partial_inplace==false) {
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486 output_base = 0;
487 }
e98e6ec1 488 else {
5022aea5 489 output_base = reloc_target_output_section->vma;
985fca12 490
5022aea5 491 }
985fca12 492
65cab589 493 relocation += output_base + symbol->section->output_offset;
985fca12 494
65cab589 495 relocation += reloc_entry->addend;
985fca12 496
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497 if(reloc_entry->address > input_section->_cooked_size)
498 {
499 return bfd_reloc_outofrange;
500 }
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501
502
503 if (howto->pc_relative == true)
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504 {
505 /*
506 Anything which started out as pc relative should end up that
507 way too.
508
509 There are two ways we can see a pcrel instruction. Sometimes
510 the pcrel displacement has been partially calculated, it
511 includes the distance from the start of the section to the
65cab589
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512 instruction in it (e.g., sun3), and sometimes the field is
513 totally blank - e.g., m88kbcs.
e98e6ec1 514 */
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515
516
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517 relocation -=
518 input_section->output_section->vma + input_section->output_offset;
985fca12 519
e98e6ec1 520 if (howto->pcrel_offset == true) {
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521 relocation -= reloc_entry->address;
522 }
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523 }
524
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525 if (output_bfd!= (bfd *)NULL)
526 {
527 if ( howto->partial_inplace == false)
528 {
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529 /*
530 This is a partial relocation, and we want to apply the relocation
531 to the reloc entry rather than the raw data. Modify the reloc
532 inplace to reflect what we now know.
533 */
534 reloc_entry->addend = relocation ;
535 reloc_entry->address += input_section->output_offset;
536 return flag;
537 }
538 else
539 {
540 /* This is a partial relocation, but inplace, so modify the
541 reloc record a bit.
542
543 If we've relocated with a symbol with a section, change
544 into a ref to the section belonging to the symbol
545 */
e98e6ec1 546
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547 reloc_entry->address += input_section->output_offset;
548
549 if (abfd->xvec->flavour == bfd_target_coff_flavour)
550 {
551 relocation -= reloc_entry->addend;
552 reloc_entry->addend = 0;
553 }
554 else
555 {
556 reloc_entry->addend = relocation ;
557 }
985fca12 558 }
5022aea5 559 }
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560 else
561 {
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562 reloc_entry->addend = 0;
563 }
e98e6ec1 564
985fca12 565
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566 if (howto->complain_on_overflow && howto->pc_relative)
567 {
568 /* We can detect overflow safely here */
569
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570 bfd_signed_vma reloc_max = (1 << (howto->bitsize - 1))-1;
571 bfd_signed_vma reloc_min = ~(reloc_max);
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572
573 if ((bfd_signed_vma) relocation > reloc_max
574 || (bfd_signed_vma) relocation < reloc_min)
575 {
576 flag = bfd_reloc_overflow;
577 }
578 }
579
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580 /*
581 Either we are relocating all the way, or we don't want to apply
582 the relocation to the reloc entry (probably because there isn't
583 any room in the output format to describe addends to relocs)
584 */
585 relocation >>= howto->rightshift;
586
587 /* Shift everything up to where it's going to be used */
588
589 relocation <<= howto->bitpos;
590
591 /* Wait for the day when all have the mask in them */
592
593 /* What we do:
594 i instruction to be left alone
595 o offset within instruction
596 r relocation offset to apply
597 S src mask
598 D dst mask
599 N ~dst mask
600 A part 1
601 B part 2
602 R result
603
604 Do this:
605 i i i i i o o o o o from bfd_get<size>
606 and S S S S S to get the size offset we want
607 + r r r r r r r r r r to get the final value to place
608 and D D D D D to chop to right size
609 -----------------------
610 A A A A A
611 And this:
612 ... i i i i i o o o o o from bfd_get<size>
613 and N N N N N get instruction
614 -----------------------
615 ... B B B B B
616
617 And then:
618 B B B B B
619 or A A A A A
620 -----------------------
621 R R R R R R R R R R put into bfd_put<size>
622 */
623
624#define DOIT(x) \
625 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
626
e98e6ec1 627 switch (howto->size)
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628 {
629 case 0:
630 {
631 char x = bfd_get_8(abfd, (char *)data + addr);
632 DOIT(x);
633 bfd_put_8(abfd,x, (unsigned char *) data + addr);
634 }
635 break;
636
637 case 1:
638 if (relocation)
639 {
640 short x = bfd_get_16(abfd, (bfd_byte *)data + addr);
641 DOIT(x);
642 bfd_put_16(abfd, x, (unsigned char *)data + addr);
643 }
644 break;
645 case 2:
646 if (relocation)
647 {
648 long x = bfd_get_32 (abfd, (bfd_byte *) data + addr);
649 DOIT (x);
650 bfd_put_32 (abfd, x, (bfd_byte *)data + addr);
651 }
652 break;
653 case -2:
654 {
655 long x = bfd_get_32(abfd, (bfd_byte *) data + addr);
656 relocation = -relocation;
657 DOIT(x);
658 bfd_put_32(abfd,x, (bfd_byte *)data + addr);
659 }
660 break;
661
662 case 3:
663
664 /* Do nothing */
665 break;
666 default:
667 return bfd_reloc_other;
668 }
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669
670 return flag;
671}
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672
673
2cf44d7b 674
0cda46cf 675/*
c26d7d17 676DOCDD
e98e6ec1
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677INODE
678 howto manager, , typedef arelent, Relocations
679
0cda46cf
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680SECTION
681 The howto manager
2cf44d7b 682
0cda46cf
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683 When an application wants to create a relocation, but doesn't
684 know what the target machine might call it, it can find out by
685 using this bit of code.
2cf44d7b 686
0cda46cf 687*/
2cf44d7b 688
0cda46cf
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689/*
690TYPEDEF
691 bfd_reloc_code_type
2cf44d7b 692
0cda46cf
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693DESCRIPTION
694 The insides of a reloc code
695
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696CODE_FRAGMENT
697.
698.typedef enum bfd_reloc_code_real
c26d7d17 699.
e98e6ec1 700.{
defcfb55
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701. {* 64 bits wide, simple reloc *}
702. BFD_RELOC_64,
703. {* 64 bits, PC-relative *}
704. BFD_RELOC_64_PCREL,
705.
706. {* 32 bits wide, simple reloc *}
707. BFD_RELOC_32,
708. {* 32 bits, PC-relative *}
709. BFD_RELOC_32_PCREL,
710.
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711. {* 16 bits wide, simple reloc *}
712. BFD_RELOC_16,
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713. {* 16 bits, PC-relative *}
714. BFD_RELOC_16_PCREL,
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715.
716. {* 8 bits wide, simple *}
0cda46cf 717. BFD_RELOC_8,
e98e6ec1 718. {* 8 bits wide, pc relative *}
0cda46cf 719. BFD_RELOC_8_PCREL,
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720. {* 8 bits wide, but used to form an address like 0xffnn *}
721. BFD_RELOC_8_FFnn,
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722.
723. {* The type of reloc used to build a contructor table - at the
724. moment probably a 32 bit wide abs address, but the cpu can
725. choose. *}
726.
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727. BFD_RELOC_CTOR,
728.
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729. {* High 22 bits of 32-bit value; simple reloc. *}
730. BFD_RELOC_HI22,
731. {* Low 10 bits. *}
732. BFD_RELOC_LO10,
733.
734. {* Reloc types used for i960/b.out. *}
735. BFD_RELOC_24_PCREL,
736. BFD_RELOC_I960_CALLJ,
737.
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738. {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit
739. word displacement, e.g. for SPARC) *}
740. BFD_RELOC_32_PCREL_S2,
741.
742. {* now for the sparc/elf codes *}
743. BFD_RELOC_NONE, {* actually used *}
744. BFD_RELOC_SPARC_WDISP22,
745. BFD_RELOC_SPARC22,
746. BFD_RELOC_SPARC13,
747. BFD_RELOC_SPARC_BASE13,
748. BFD_RELOC_SPARC_GOT10,
749. BFD_RELOC_SPARC_GOT13,
750. BFD_RELOC_SPARC_GOT22,
751. BFD_RELOC_SPARC_PC10,
752. BFD_RELOC_SPARC_PC22,
753. BFD_RELOC_SPARC_WPLT30,
754. BFD_RELOC_SPARC_COPY,
755. BFD_RELOC_SPARC_GLOB_DAT,
756. BFD_RELOC_SPARC_JMP_SLOT,
757. BFD_RELOC_SPARC_RELATIVE,
758. BFD_RELOC_SPARC_UA32,
759.
760. {* this one is a.out specific? *}
761. BFD_RELOC_SPARC_BASE22,
762.
defcfb55
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763. {* start-sanitize-v9 *}
764. BFD_RELOC_SPARC_WDISP19,
765. BFD_RELOC_SPARC_10,
766. BFD_RELOC_SPARC_11,
767.#define BFD_RELOC_SPARC_64 BFD_RELOC_64
768. BFD_RELOC_SPARC_OLO10,
769. BFD_RELOC_SPARC_HH22,
770. BFD_RELOC_SPARC_HM10,
771. BFD_RELOC_SPARC_LM22,
772. BFD_RELOC_SPARC_PC_HH22,
773. BFD_RELOC_SPARC_PC_HM10,
774. BFD_RELOC_SPARC_PC_LM22,
775. BFD_RELOC_SPARC_WDISP16,
776. BFD_RELOC_SPARC_GLOB_JMP,
777. BFD_RELOC_SPARC_LO7,
778. {* end-sanitize-v9 *}
65cab589
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779. {* Bits 27..2 of the relocation address shifted right 2 bits;
780. simple reloc otherwise. *}
781. BFD_RELOC_MIPS_JMP,
782.
783. {* signed 16-bit pc-relative, shifted right 2 bits (e.g. for MIPS) *}
784. BFD_RELOC_16_PCREL_S2,
785.
786. {* High 16 bits of 32-bit value; simple reloc. *}
787. BFD_RELOC_HI16,
788. {* High 16 bits of 32-bit value but the low 16 bits will be sign
789. extended and added to form the final result. If the low 16
790. bits form a negative number, we need to add one to the high value
791. to compensate for the borrow when the low bits are added. *}
792. BFD_RELOC_HI16_S,
793. {* Low 16 bits. *}
794. BFD_RELOC_LO16,
795.
796. {* 16 bit relocation relative to the global pointer. *}
797. BFD_RELOC_MIPS_GPREL,
798.
799. {* These are, so far, specific to HPPA processors. I'm not sure that
800. some don't duplicate other reloc types, such as BFD_RELOC_32 and
801. _32_PCREL. Also, many more were in the list I got that don't
802. fit in well in the model BFD uses, so I've omitted them for now.
803. If we do make this reloc type get used for code that really does
804. implement the funky reloc types, they'll have to be added to this
805. list. *}
806. BFD_RELOC_HPPA_32,
807. BFD_RELOC_HPPA_11,
808. BFD_RELOC_HPPA_14,
809. BFD_RELOC_HPPA_17,
810. BFD_RELOC_HPPA_L21,
811. BFD_RELOC_HPPA_R11,
812. BFD_RELOC_HPPA_R14,
813. BFD_RELOC_HPPA_R17,
814. BFD_RELOC_HPPA_LS21,
815. BFD_RELOC_HPPA_RS11,
816. BFD_RELOC_HPPA_RS14,
817. BFD_RELOC_HPPA_RS17,
818. BFD_RELOC_HPPA_LD21,
819. BFD_RELOC_HPPA_RD11,
820. BFD_RELOC_HPPA_RD14,
821. BFD_RELOC_HPPA_RD17,
822. BFD_RELOC_HPPA_LR21,
823. BFD_RELOC_HPPA_RR14,
824. BFD_RELOC_HPPA_RR17,
825. BFD_RELOC_HPPA_GOTOFF_11,
826. BFD_RELOC_HPPA_GOTOFF_14,
827. BFD_RELOC_HPPA_GOTOFF_L21,
828. BFD_RELOC_HPPA_GOTOFF_R11,
829. BFD_RELOC_HPPA_GOTOFF_R14,
830. BFD_RELOC_HPPA_GOTOFF_LS21,
831. BFD_RELOC_HPPA_GOTOFF_RS11,
832. BFD_RELOC_HPPA_GOTOFF_RS14,
833. BFD_RELOC_HPPA_GOTOFF_LD21,
834. BFD_RELOC_HPPA_GOTOFF_RD11,
835. BFD_RELOC_HPPA_GOTOFF_RD14,
836. BFD_RELOC_HPPA_GOTOFF_LR21,
837. BFD_RELOC_HPPA_GOTOFF_RR14,
838. BFD_RELOC_HPPA_DLT_32,
839. BFD_RELOC_HPPA_DLT_11,
840. BFD_RELOC_HPPA_DLT_14,
841. BFD_RELOC_HPPA_DLT_L21,
842. BFD_RELOC_HPPA_DLT_R11,
843. BFD_RELOC_HPPA_DLT_R14,
844. BFD_RELOC_HPPA_ABS_CALL_11,
845. BFD_RELOC_HPPA_ABS_CALL_14,
846. BFD_RELOC_HPPA_ABS_CALL_17,
847. BFD_RELOC_HPPA_ABS_CALL_L21,
848. BFD_RELOC_HPPA_ABS_CALL_R11,
849. BFD_RELOC_HPPA_ABS_CALL_R14,
850. BFD_RELOC_HPPA_ABS_CALL_R17,
851. BFD_RELOC_HPPA_ABS_CALL_LS21,
852. BFD_RELOC_HPPA_ABS_CALL_RS11,
853. BFD_RELOC_HPPA_ABS_CALL_RS14,
854. BFD_RELOC_HPPA_ABS_CALL_RS17,
855. BFD_RELOC_HPPA_ABS_CALL_LD21,
856. BFD_RELOC_HPPA_ABS_CALL_RD11,
857. BFD_RELOC_HPPA_ABS_CALL_RD14,
858. BFD_RELOC_HPPA_ABS_CALL_RD17,
859. BFD_RELOC_HPPA_ABS_CALL_LR21,
860. BFD_RELOC_HPPA_ABS_CALL_RR14,
861. BFD_RELOC_HPPA_ABS_CALL_RR17,
862. BFD_RELOC_HPPA_PCREL_CALL_11,
863. BFD_RELOC_HPPA_PCREL_CALL_12,
864. BFD_RELOC_HPPA_PCREL_CALL_14,
865. BFD_RELOC_HPPA_PCREL_CALL_17,
866. BFD_RELOC_HPPA_PCREL_CALL_L21,
867. BFD_RELOC_HPPA_PCREL_CALL_R11,
868. BFD_RELOC_HPPA_PCREL_CALL_R14,
869. BFD_RELOC_HPPA_PCREL_CALL_R17,
870. BFD_RELOC_HPPA_PCREL_CALL_LS21,
871. BFD_RELOC_HPPA_PCREL_CALL_RS11,
872. BFD_RELOC_HPPA_PCREL_CALL_RS14,
873. BFD_RELOC_HPPA_PCREL_CALL_RS17,
874. BFD_RELOC_HPPA_PCREL_CALL_LD21,
875. BFD_RELOC_HPPA_PCREL_CALL_RD11,
876. BFD_RELOC_HPPA_PCREL_CALL_RD14,
877. BFD_RELOC_HPPA_PCREL_CALL_RD17,
878. BFD_RELOC_HPPA_PCREL_CALL_LR21,
879. BFD_RELOC_HPPA_PCREL_CALL_RR14,
880. BFD_RELOC_HPPA_PCREL_CALL_RR17,
881. BFD_RELOC_HPPA_PLABEL_32,
882. BFD_RELOC_HPPA_PLABEL_11,
883. BFD_RELOC_HPPA_PLABEL_14,
884. BFD_RELOC_HPPA_PLABEL_L21,
885. BFD_RELOC_HPPA_PLABEL_R11,
886. BFD_RELOC_HPPA_PLABEL_R14,
887. BFD_RELOC_HPPA_UNWIND_ENTRY,
888. BFD_RELOC_HPPA_UNWIND_ENTRIES,
889.
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890. {* this must be the highest numeric value *}
891. BFD_RELOC_UNUSED
0cda46cf 892. } bfd_reloc_code_real_type;
2cf44d7b
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893*/
894
895
896
0cda46cf
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897/*
898SECTION
899 bfd_reloc_type_lookup
2cf44d7b 900
e98e6ec1
SC
901SYNOPSIS
902 CONST struct reloc_howto_struct *
3860075f 903 bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code);
e98e6ec1 904
0cda46cf
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905DESCRIPTION
906 This routine returns a pointer to a howto struct which when
907 invoked, will perform the supplied relocation on data from the
908 architecture noted.
2cf44d7b 909
2cf44d7b
SC
910*/
911
912
913CONST struct reloc_howto_struct *
3860075f 914DEFUN(bfd_reloc_type_lookup,(abfd, code),
8070f29d 915 bfd *abfd AND
3860075f 916 bfd_reloc_code_real_type code)
2cf44d7b 917{
8070f29d 918 return BFD_SEND (abfd, reloc_type_lookup, (abfd, code));
2cf44d7b
SC
919}
920
0cda46cf
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921static reloc_howto_type bfd_howto_32 =
922 HOWTO(0, 00,2,32,false,0,false,true,0,"VRT32", false,0xffffffff,0xffffffff,true);
2cf44d7b
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923
924
0cda46cf 925/*
e98e6ec1 926INTERNAL_FUNCTION
0cda46cf
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927 bfd_default_reloc_type_lookup
928
0cda46cf
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929SYNOPSIS
930 CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup
65cab589 931 (bfd *abfd AND
3860075f 932 bfd_reloc_code_real_type code);
0cda46cf 933
e98e6ec1 934DESCRIPTION
65cab589 935 Provides a default relocation lookup routine for any architecture.
e98e6ec1
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936
937
0cda46cf 938*/
65cab589 939
0cda46cf 940CONST struct reloc_howto_struct *
65cab589
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941DEFUN(bfd_default_reloc_type_lookup, (abfd, code),
942 bfd *abfd AND
943 bfd_reloc_code_real_type code)
0cda46cf 944{
65cab589 945 switch (code)
0cda46cf 946 {
65cab589
DM
947 case BFD_RELOC_CTOR:
948 /* The type of reloc used in a ctor, which will be as wide as the
949 address - so either a 64, 32, or 16 bitter.. */
950 switch (bfd_get_arch_info (abfd)->bits_per_address) {
951 case 64:
952 BFD_FAIL();
953 case 32:
954 return &bfd_howto_32;
955 case 16:
956 BFD_FAIL();
957 default:
0cda46cf 958 BFD_FAIL();
65cab589
DM
959 }
960 default:
961 BFD_FAIL();
0cda46cf 962 }
65cab589 963 return (CONST struct reloc_howto_struct *)NULL;
0cda46cf 964}
e98e6ec1
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965
966
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967/*
968INTERNAL_FUNCTION
969 bfd_generic_relax_section
970
971SYNOPSIS
972 boolean bfd_generic_relax_section
973 (bfd *abfd,
974 asection *section,
5022aea5 975 asymbol **symbols);
d58b7049
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976
977DESCRIPTION
978 Provides default handling for relaxing for back ends which
8070f29d 979 don't do relaxing -- i.e., does nothing.
d58b7049
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980*/
981
982boolean
5022aea5 983DEFUN(bfd_generic_relax_section,(abfd, section, symbols),
d58b7049
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984 bfd *abfd AND
985 asection *section AND
5022aea5 986 asymbol **symbols)
d58b7049
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987{
988
989 return false;
990
991}
e98e6ec1 992
d58b7049 993
e98e6ec1
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994/*
995INTERNAL_FUNCTION
996 bfd_generic_get_relocated_section_contents
997
998SYNOPSIS
999 bfd_byte *
65cab589
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1000 bfd_generic_get_relocated_section_contents (bfd *abfd,
1001 struct bfd_seclet *seclet,
1002 bfd_byte *data,
1003 boolean relocateable);
e98e6ec1
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1004
1005DESCRIPTION
1006 Provides default handling of relocation effort for back ends
1007 which can't be bothered to do it efficiently.
1008
1009*/
1010
1011bfd_byte *
65cab589
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1012DEFUN(bfd_generic_get_relocated_section_contents,(abfd,
1013 seclet,
1014 data,
1015 relocateable),
e98e6ec1 1016 bfd *abfd AND
65cab589
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1017 struct bfd_seclet *seclet AND
1018 bfd_byte *data AND
1019 boolean relocateable)
e98e6ec1
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1020{
1021 extern bfd_error_vector_type bfd_error_vector;
e98e6ec1
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1022
1023 /* Get enough memory to hold the stuff */
1024 bfd *input_bfd = seclet->u.indirect.section->owner;
1025 asection *input_section = seclet->u.indirect.section;
1026
8070f29d 1027
e98e6ec1 1028
defcfb55 1029 size_t reloc_size = bfd_get_reloc_upper_bound(input_bfd, input_section);
8070f29d 1030 arelent **reloc_vector = (arelent **) alloca(reloc_size);
e98e6ec1
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1031
1032 /* read in the section */
1033 bfd_get_section_contents(input_bfd,
1034 input_section,
1035 data,
1036 0,
1037 input_section->_raw_size);
1038
1039/* We're not relaxing the section, so just copy the size info */
1040 input_section->_cooked_size = input_section->_raw_size;
1041 input_section->reloc_done = true;
1042
1043
1044 if (bfd_canonicalize_reloc(input_bfd,
1045 input_section,
1046 reloc_vector,
1047 seclet->u.indirect.symbols) )
1048 {
1049 arelent **parent;
1050 for (parent = reloc_vector; * parent != (arelent *)NULL;
1051 parent++)
1052 {
1053 bfd_reloc_status_type r=
1054 bfd_perform_relocation(input_bfd,
1055 *parent,
1056 data,
65cab589
DM
1057 input_section,
1058 relocateable ? abfd : (bfd *) NULL);
e98e6ec1 1059
65cab589
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1060 if (relocateable)
1061 {
1062 asection *os = input_section->output_section;
1063
1064 /* A partial link, so keep the relocs */
1065 os->orelocation[os->reloc_count] = *parent;
1066 os->reloc_count++;
1067 }
e98e6ec1
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1068
1069 if (r != bfd_reloc_ok)
1070 {
e98e6ec1
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1071 switch (r)
1072 {
1073 case bfd_reloc_undefined:
1074 bfd_error_vector.undefined_symbol(*parent, seclet);
1075 break;
1076 case bfd_reloc_dangerous:
1077 bfd_error_vector.reloc_dangerous(*parent, seclet);
1078 break;
1079 case bfd_reloc_outofrange:
1080 case bfd_reloc_overflow:
1081 bfd_error_vector.reloc_value_truncated(*parent, seclet);
1082 break;
1083 default:
1084 abort();
1085 break;
1086 }
1087
1088 }
1089 }
1090 }
1091
8070f29d 1092
e98e6ec1
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1093 return data;
1094
1095
1096}
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