xref: /openbsd/gnu/usr.bin/binutils/bfd/coff-x86_64.c (revision 771fbea0)
1 /* BFD back-end for AMD 64 COFF files.
2    Copyright 2006, 2007 Free Software Foundation, Inc.
3 
4    This file is part of BFD, the Binary File Descriptor library.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 2 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
19 
20    Written by Kai Tietz, OneVision Software GmbH&CoKg.  */
21 
22 #ifndef COFF_WITH_pex64
23 #define COFF_WITH_pex64
24 #endif
25 
26 #include "sysdep.h"
27 #include "bfd.h"
28 #include "libbfd.h"
29 #include "coff/x86_64.h"
30 #include "coff/internal.h"
31 #include "coff/pe.h"
32 #include "libcoff.h"
33 #include "libiberty.h"
34 
35 #define BADMAG(x) AMD64BADMAG(x)
36 
37 #ifdef COFF_WITH_pex64
38 # undef  AOUTSZ
39 # define AOUTSZ		PEPAOUTSZ
40 # define PEAOUTHDR	PEPAOUTHDR
41 #endif
42 
43 #define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
44 
45 /* The page size is a guess based on ELF.  */
46 
47 #define COFF_PAGE_SIZE 0x1000
48 
49 /* For some reason when using AMD COFF the value stored in the .text
50    section for a reference to a common symbol is the value itself plus
51    any desired offset.  Ian Taylor, Cygnus Support.  */
52 
53 /* If we are producing relocatable output, we need to do some
54    adjustments to the object file that are not done by the
55    bfd_perform_relocation function.  This function is called by every
56    reloc type to make any required adjustments.  */
57 
58 static bfd_reloc_status_type
59 coff_amd64_reloc (bfd *abfd,
60 		  arelent *reloc_entry,
61 		  asymbol *symbol,
62 		  void * data,
63 		  asection *input_section ATTRIBUTE_UNUSED,
64 		  bfd *output_bfd,
65 		  char **error_message ATTRIBUTE_UNUSED)
66 {
67   symvalue diff;
68 
69 #if !defined(COFF_WITH_PE)
70   if (output_bfd == NULL)
71     return bfd_reloc_continue;
72 #endif
73 
74   if (bfd_is_com_section (symbol->section))
75     {
76 #if !defined(COFF_WITH_PE)
77       /* We are relocating a common symbol.  The current value in the
78 	 object file is ORIG + OFFSET, where ORIG is the value of the
79 	 common symbol as seen by the object file when it was compiled
80 	 (this may be zero if the symbol was undefined) and OFFSET is
81 	 the offset into the common symbol (normally zero, but may be
82 	 non-zero when referring to a field in a common structure).
83 	 ORIG is the negative of reloc_entry->addend, which is set by
84 	 the CALC_ADDEND macro below.  We want to replace the value in
85 	 the object file with NEW + OFFSET, where NEW is the value of
86 	 the common symbol which we are going to put in the final
87 	 object file.  NEW is symbol->value.  */
88       diff = symbol->value + reloc_entry->addend;
89 #else
90       /* In PE mode, we do not offset the common symbol.  */
91       diff = reloc_entry->addend;
92 #endif
93     }
94   else
95     {
96       /* For some reason bfd_perform_relocation always effectively
97 	 ignores the addend for a COFF target when producing
98 	 relocatable output.  This seems to be always wrong for 386
99 	 COFF, so we handle the addend here instead.  */
100 #if defined(COFF_WITH_PE)
101       if (output_bfd == NULL)
102 	{
103 	  reloc_howto_type *howto = reloc_entry->howto;
104 
105 	  /* Although PC relative relocations are very similar between
106 	     PE and non-PE formats, but they are off by 1 << howto->size
107 	     bytes. For the external relocation, PE is very different
108 	     from others. See md_apply_fix3 () in gas/config/tc-amd64.c.
109 	     When we link PE and non-PE object files together to
110 	     generate a non-PE executable, we have to compensate it
111 	     here.  */
112 	  if(howto->pc_relative && howto->pcrel_offset)
113 	    diff = -(1 << howto->size);
114 	  else if(symbol->flags & BSF_WEAK)
115 	    diff = reloc_entry->addend - symbol->value;
116 	  else
117 	    diff = -reloc_entry->addend;
118 	}
119       else
120 #endif
121 	diff = reloc_entry->addend;
122     }
123 
124 #if defined(COFF_WITH_PE)
125   /* FIXME: How should this case be handled?  */
126   if (reloc_entry->howto->type == R_AMD64_IMAGEBASE
127       && output_bfd != NULL
128       && bfd_get_flavour (output_bfd) == bfd_target_coff_flavour)
129     diff -= pe_data (output_bfd)->pe_opthdr.ImageBase;
130 #endif
131 
132 #define DOIT(x) \
133   x = ((x & ~howto->dst_mask) | (((x & howto->src_mask) + diff) & howto->dst_mask))
134 
135     if (diff != 0)
136       {
137 	reloc_howto_type *howto = reloc_entry->howto;
138 	unsigned char *addr = (unsigned char *) data + reloc_entry->address;
139 
140 	switch (howto->size)
141 	  {
142 	  case 0:
143 	    {
144 	      char x = bfd_get_8 (abfd, addr);
145 	      DOIT (x);
146 	      bfd_put_8 (abfd, x, addr);
147 	    }
148 	    break;
149 
150 	  case 1:
151 	    {
152 	      short x = bfd_get_16 (abfd, addr);
153 	      DOIT (x);
154 	      bfd_put_16 (abfd, (bfd_vma) x, addr);
155 	    }
156 	    break;
157 
158 	  case 2:
159 	    {
160 	      long x = bfd_get_32 (abfd, addr);
161 	      DOIT (x);
162 	      bfd_put_32 (abfd, (bfd_vma) x, addr);
163 	    }
164 	    break;
165 	  case 4:
166 	    {
167 	      long long x = bfd_get_64 (abfd, addr);
168 	      DOIT (x);
169 	      bfd_put_64 (abfd, (bfd_vma) x, addr);
170 	    }
171 	    break;
172 
173 	  default:
174 	    abort ();
175 	  }
176       }
177 
178   /* Now let bfd_perform_relocation finish everything up.  */
179   return bfd_reloc_continue;
180 }
181 
182 #if defined(COFF_WITH_PE)
183 /* Return TRUE if this relocation should appear in the output .reloc
184    section.  */
185 
186 static bfd_boolean
187 in_reloc_p (bfd *abfd ATTRIBUTE_UNUSED, reloc_howto_type *howto)
188 {
189   return ! howto->pc_relative && howto->type != R_AMD64_IMAGEBASE;
190 }
191 #endif /* COFF_WITH_PE */
192 
193 #ifndef PCRELOFFSET
194 #define PCRELOFFSET TRUE
195 #endif
196 
197 static reloc_howto_type howto_table[] =
198 {
199   EMPTY_HOWTO (0),
200   HOWTO (R_AMD64_DIR64,		/* type  1*/
201 	 0,			/* rightshift */
202 	 4,			/* size (0 = byte, 1 = short, 2 = long, 4 = long long) */
203 	 64,			/* bitsize */
204 	 FALSE,			/* pc_relative */
205 	 0,			/* bitpos */
206 	 complain_overflow_bitfield, /* complain_on_overflow */
207 	 coff_amd64_reloc,	/* special_function */
208 	 "R_X86_64_64",		/* name */
209 	 TRUE,			/* partial_inplace */
210 	 0xffffffffffffffffll,	/* src_mask */
211 	 0xffffffffffffffffll,	/* dst_mask */
212 	 TRUE),			/* pcrel_offset */
213   HOWTO (R_AMD64_DIR32,		/* type 2 */
214 	 0,			/* rightshift */
215 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
216 	 32,			/* bitsize */
217 	 FALSE,			/* pc_relative */
218 	 0,			/* bitpos */
219 	 complain_overflow_bitfield, /* complain_on_overflow */
220 	 coff_amd64_reloc,	/* special_function */
221 	 "R_X86_64_32",		/* name */
222 	 TRUE,			/* partial_inplace */
223 	 0xffffffff,		/* src_mask */
224 	 0xffffffff,		/* dst_mask */
225 	 TRUE),			/* pcrel_offset */
226   /* PE IMAGE_REL_AMD64_ADDR32NB relocation (3).	*/
227   HOWTO (R_AMD64_IMAGEBASE,	/* type */
228 	 0,			/* rightshift */
229 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
230 	 32,			/* bitsize */
231 	 FALSE,			/* pc_relative */
232 	 0,			/* bitpos */
233 	 complain_overflow_bitfield, /* complain_on_overflow */
234 	 coff_amd64_reloc,	/* special_function */
235 	 "rva32",		/* name */
236 	 TRUE,			/* partial_inplace */
237 	 0xffffffff,		/* src_mask */
238 	 0xffffffff,		/* dst_mask */
239 	 FALSE),		/* pcrel_offset */
240   /* 32-bit longword PC relative relocation (4).  */
241   HOWTO (R_AMD64_PCRLONG,	/* type 4 */
242 	 0,			/* rightshift */
243 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
244 	 32,			/* bitsize */
245 	 TRUE,			/* pc_relative */
246 	 0,			/* bitpos */
247 	 complain_overflow_signed, /* complain_on_overflow */
248 	 coff_amd64_reloc,	/* special_function */
249 	 "R_X86_64_PC32",	/* name */
250 	 TRUE,			/* partial_inplace */
251 	 0xffffffff,		/* src_mask */
252 	 0xffffffff,		/* dst_mask */
253 	 PCRELOFFSET),		/* pcrel_offset */
254 
255  HOWTO (R_AMD64_PCRLONG_1,	/* type 5 */
256 	 0,			/* rightshift */
257 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
258 	 32,			/* bitsize */
259 	 TRUE,			/* pc_relative */
260 	 0,			/* bitpos */
261 	 complain_overflow_signed, /* complain_on_overflow */
262 	 coff_amd64_reloc,	/* special_function */
263 	 "DISP32+1",		/* name */
264 	 TRUE,			/* partial_inplace */
265 	 0xffffffff,		/* src_mask */
266 	 0xffffffff,		/* dst_mask */
267 	 PCRELOFFSET),		/* pcrel_offset */
268  HOWTO (R_AMD64_PCRLONG_2,	/* type 6 */
269 	 0,			/* rightshift */
270 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
271 	 32,			/* bitsize */
272 	 TRUE,			/* pc_relative */
273 	 0,			/* bitpos */
274 	 complain_overflow_signed, /* complain_on_overflow */
275 	 coff_amd64_reloc,	/* special_function */
276 	 "DISP32+2",		/* name */
277 	 TRUE,			/* partial_inplace */
278 	 0xffffffff,		/* src_mask */
279 	 0xffffffff,		/* dst_mask */
280 	 PCRELOFFSET),		/* pcrel_offset */
281  HOWTO (R_AMD64_PCRLONG_3,	/* type 7 */
282 	 0,			/* rightshift */
283 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
284 	 32,			/* bitsize */
285 	 TRUE,			/* pc_relative */
286 	 0,			/* bitpos */
287 	 complain_overflow_signed, /* complain_on_overflow */
288 	 coff_amd64_reloc,	/* special_function */
289 	 "DISP32+3",		/* name */
290 	 TRUE,			/* partial_inplace */
291 	 0xffffffff,		/* src_mask */
292 	 0xffffffff,		/* dst_mask */
293 	 PCRELOFFSET),		/* pcrel_offset */
294  HOWTO (R_AMD64_PCRLONG_4,	/* type 8 */
295 	 0,			/* rightshift */
296 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
297 	 32,			/* bitsize */
298 	 TRUE,			/* pc_relative */
299 	 0,			/* bitpos */
300 	 complain_overflow_signed, /* complain_on_overflow */
301 	 coff_amd64_reloc,	/* special_function */
302 	 "DISP32+4",		/* name */
303 	 TRUE,			/* partial_inplace */
304 	 0xffffffff,		/* src_mask */
305 	 0xffffffff,		/* dst_mask */
306 	 PCRELOFFSET),		/* pcrel_offset */
307  HOWTO (R_AMD64_PCRLONG_5,	/* type 9 */
308 	 0,			/* rightshift */
309 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
310 	 32,			/* bitsize */
311 	 TRUE,			/* pc_relative */
312 	 0,			/* bitpos */
313 	 complain_overflow_signed, /* complain_on_overflow */
314 	 coff_amd64_reloc,	/* special_function */
315 	 "DISP32+5",		/* name */
316 	 TRUE,			/* partial_inplace */
317 	 0xffffffff,		/* src_mask */
318 	 0xffffffff,		/* dst_mask */
319 	 PCRELOFFSET),		/* pcrel_offset */
320   EMPTY_HOWTO (10), /* R_AMD64_SECTION 10  */
321 #if defined(COFF_WITH_PE)
322   /* 32-bit longword section relative relocation (11).  */
323   HOWTO (R_AMD64_SECREL,	/* type */
324 	 0,			/* rightshift */
325 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
326 	 32,			/* bitsize */
327 	 FALSE,			/* pc_relative */
328 	 0,			/* bitpos */
329 	 complain_overflow_bitfield, /* complain_on_overflow */
330 	 coff_amd64_reloc,	/* special_function */
331 	 "secrel32",		/* name */
332 	 TRUE,			/* partial_inplace */
333 	 0xffffffff,		/* src_mask */
334 	 0xffffffff,		/* dst_mask */
335 	 TRUE),			/* pcrel_offset */
336 #else
337   EMPTY_HOWTO (11),
338 #endif
339   EMPTY_HOWTO (12),
340   EMPTY_HOWTO (13),
341 #ifndef DONT_EXTEND_AMD64
342   HOWTO (R_AMD64_PCRQUAD,
343          0,                     /* rightshift */
344          4,                     /* size (0 = byte, 1 = short, 2 = long) */
345          64,                    /* bitsize */
346          TRUE,                  /* pc_relative */
347          0,                     /* bitpos */
348          complain_overflow_signed, /* complain_on_overflow */
349          coff_amd64_reloc,      /* special_function */
350          "R_X86_64_PC64",       /* name */
351          TRUE,                  /* partial_inplace */
352          0xffffffffffffffffll,  /* src_mask */
353          0xffffffffffffffffll,  /* dst_mask */
354          PCRELOFFSET),           /* pcrel_offset */
355 #else
356   EMPTY_HOWTO (14),
357 #endif
358   /* Byte relocation (15).  */
359   HOWTO (R_RELBYTE,		/* type */
360 	 0,			/* rightshift */
361 	 0,			/* size (0 = byte, 1 = short, 2 = long) */
362 	 8,			/* bitsize */
363 	 FALSE,			/* pc_relative */
364 	 0,			/* bitpos */
365 	 complain_overflow_bitfield, /* complain_on_overflow */
366 	 coff_amd64_reloc,	/* special_function */
367 	 "R_X86_64_8",		/* name */
368 	 TRUE,			/* partial_inplace */
369 	 0x000000ff,		/* src_mask */
370 	 0x000000ff,		/* dst_mask */
371 	 PCRELOFFSET),		/* pcrel_offset */
372   /* 16-bit word relocation (16).  */
373   HOWTO (R_RELWORD,		/* type */
374 	 0,			/* rightshift */
375 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
376 	 16,			/* bitsize */
377 	 FALSE,			/* pc_relative */
378 	 0,			/* bitpos */
379 	 complain_overflow_bitfield, /* complain_on_overflow */
380 	 coff_amd64_reloc,	/* special_function */
381 	 "R_X86_64_16",		/* name */
382 	 TRUE,			/* partial_inplace */
383 	 0x0000ffff,		/* src_mask */
384 	 0x0000ffff,		/* dst_mask */
385 	 PCRELOFFSET),		/* pcrel_offset */
386   /* 32-bit longword relocation (17).	*/
387   HOWTO (R_RELLONG,		/* type */
388 	 0,			/* rightshift */
389 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
390 	 32,			/* bitsize */
391 	 FALSE,			/* pc_relative */
392 	 0,			/* bitpos */
393 	 complain_overflow_bitfield, /* complain_on_overflow */
394 	 coff_amd64_reloc,	/* special_function */
395 	 "R_X86_64_32S",	/* name */
396 	 TRUE,			/* partial_inplace */
397 	 0xffffffff,		/* src_mask */
398 	 0xffffffff,		/* dst_mask */
399 	 PCRELOFFSET),		/* pcrel_offset */
400   /* Byte PC relative relocation (18).	 */
401   HOWTO (R_PCRBYTE,		/* type */
402 	 0,			/* rightshift */
403 	 0,			/* size (0 = byte, 1 = short, 2 = long) */
404 	 8,			/* bitsize */
405 	 TRUE,			/* pc_relative */
406 	 0,			/* bitpos */
407 	 complain_overflow_signed, /* complain_on_overflow */
408 	 coff_amd64_reloc,	/* special_function */
409 	 "R_X86_64_PC8",	/* name */
410 	 TRUE,			/* partial_inplace */
411 	 0x000000ff,		/* src_mask */
412 	 0x000000ff,		/* dst_mask */
413 	 PCRELOFFSET),		/* pcrel_offset */
414   /* 16-bit word PC relative relocation (19).	*/
415   HOWTO (R_PCRWORD,		/* type */
416 	 0,			/* rightshift */
417 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
418 	 16,			/* bitsize */
419 	 TRUE,			/* pc_relative */
420 	 0,			/* bitpos */
421 	 complain_overflow_signed, /* complain_on_overflow */
422 	 coff_amd64_reloc,	/* special_function */
423 	 "R_X86_64_PC16",	/* name */
424 	 TRUE,			/* partial_inplace */
425 	 0x0000ffff,		/* src_mask */
426 	 0x0000ffff,		/* dst_mask */
427 	 PCRELOFFSET),		/* pcrel_offset */
428   /* 32-bit longword PC relative relocation (20).  */
429   HOWTO (R_PCRLONG,		/* type */
430 	 0,			/* rightshift */
431 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
432 	 32,			/* bitsize */
433 	 TRUE,			/* pc_relative */
434 	 0,			/* bitpos */
435 	 complain_overflow_signed, /* complain_on_overflow */
436 	 coff_amd64_reloc,	/* special_function */
437 	 "R_X86_64_PC32",	/* name */
438 	 TRUE,			/* partial_inplace */
439 	 0xffffffff,		/* src_mask */
440 	 0xffffffff,		/* dst_mask */
441 	 PCRELOFFSET)		/* pcrel_offset */
442 };
443 
444 /* Turn a howto into a reloc  nunmber */
445 
446 #define SELECT_RELOC(x,howto) { x.r_type = howto->type; }
447 #define I386  1			/* Customize coffcode.h */
448 #define AMD64 1
449 
450 #define RTYPE2HOWTO(cache_ptr, dst)		\
451   ((cache_ptr)->howto =				\
452    ((dst)->r_type < ARRAY_SIZE (howto_table))	\
453     ? howto_table + (dst)->r_type		\
454     : NULL)
455 
456 /* For 386 COFF a STYP_NOLOAD | STYP_BSS section is part of a shared
457    library.  On some other COFF targets STYP_BSS is normally
458    STYP_NOLOAD.  */
459 #define BSS_NOLOAD_IS_SHARED_LIBRARY
460 
461 /* Compute the addend of a reloc.  If the reloc is to a common symbol,
462    the object file contains the value of the common symbol.  By the
463    time this is called, the linker may be using a different symbol
464    from a different object file with a different value.  Therefore, we
465    hack wildly to locate the original symbol from this file so that we
466    can make the correct adjustment.  This macro sets coffsym to the
467    symbol from the original file, and uses it to set the addend value
468    correctly.  If this is not a common symbol, the usual addend
469    calculation is done, except that an additional tweak is needed for
470    PC relative relocs.
471    FIXME: This macro refers to symbols and asect; these are from the
472    calling function, not the macro arguments.  */
473 
474 #define CALC_ADDEND(abfd, ptr, reloc, cache_ptr)		\
475   {								\
476     coff_symbol_type *coffsym = NULL;				\
477     								\
478     if (ptr && bfd_asymbol_bfd (ptr) != abfd)			\
479       coffsym = (obj_symbols (abfd)				\
480 	         + (cache_ptr->sym_ptr_ptr - symbols));		\
481     else if (ptr)						\
482       coffsym = coff_symbol_from (abfd, ptr);			\
483     								\
484     if (coffsym != NULL						\
485 	&& coffsym->native->u.syment.n_scnum == 0)		\
486       cache_ptr->addend = - coffsym->native->u.syment.n_value;	\
487     else if (ptr && bfd_asymbol_bfd (ptr) == abfd		\
488 	     && ptr->section != NULL)				\
489       cache_ptr->addend = - (ptr->section->vma + ptr->value);	\
490     else							\
491       cache_ptr->addend = 0;					\
492     if (ptr && howto_table[reloc.r_type].pc_relative)		\
493       cache_ptr->addend += asect->vma;				\
494   }
495 
496 /* We use the special COFF backend linker.  For normal AMD64 COFF, we
497    can use the generic relocate_section routine.  For PE, we need our
498    own routine.  */
499 
500 #if !defined(COFF_WITH_PE)
501 
502 #define coff_relocate_section _bfd_coff_generic_relocate_section
503 
504 #else /* COFF_WITH_PE */
505 
506 /* The PE relocate section routine.  The only difference between this
507    and the regular routine is that we don't want to do anything for a
508    relocatable link.  */
509 
510 static bfd_boolean
511 coff_pe_amd64_relocate_section (bfd *output_bfd,
512 				struct bfd_link_info *info,
513 				bfd *input_bfd,
514 				asection *input_section,
515 				bfd_byte *contents,
516 				struct internal_reloc *relocs,
517 				struct internal_syment *syms,
518 				asection **sections)
519 {
520   if (info->relocatable)
521     return TRUE;
522 
523   return _bfd_coff_generic_relocate_section (output_bfd, info, input_bfd,input_section, contents,relocs, syms, sections);
524 }
525 
526 #define coff_relocate_section coff_pe_amd64_relocate_section
527 
528 #endif /* COFF_WITH_PE */
529 
530 /* Convert an rtype to howto for the COFF backend linker.  */
531 
532 static reloc_howto_type *
533 coff_amd64_rtype_to_howto (bfd *abfd ATTRIBUTE_UNUSED,
534 			   asection *sec,
535 			   struct internal_reloc *rel,
536 			   struct coff_link_hash_entry *h,
537 			   struct internal_syment *sym,
538 			   bfd_vma *addendp)
539 {
540   reloc_howto_type *howto;
541 
542   if (rel->r_type > ARRAY_SIZE (howto_table))
543     {
544       bfd_set_error (bfd_error_bad_value);
545       return NULL;
546     }
547   if (rel->r_type >= R_AMD64_PCRLONG_1 && rel->r_type <= R_AMD64_PCRLONG_5)
548     {
549       rel->r_vaddr += (bfd_vma)(rel->r_type-R_AMD64_PCRLONG);
550       rel->r_type = R_AMD64_PCRLONG;
551     }
552   howto = howto_table + rel->r_type;
553 
554 #if defined(COFF_WITH_PE)
555   /* Cancel out code in _bfd_coff_generic_relocate_section.  */
556   *addendp = 0;
557 #endif
558 
559   if (howto->pc_relative)
560     *addendp += sec->vma;
561 
562   if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0)
563     {
564       /* This is a common symbol.  The section contents include the
565 	 size (sym->n_value) as an addend.  The relocate_section
566 	 function will be adding in the final value of the symbol.  We
567 	 need to subtract out the current size in order to get the
568 	 correct result.  */
569       BFD_ASSERT (h != NULL);
570 
571 #if !defined(COFF_WITH_PE)
572       /* I think we *do* want to bypass this.  If we don't, I have
573 	 seen some data parameters get the wrong relocation address.
574 	 If I link two versions with and without this section bypassed
575 	 and then do a binary comparison, the addresses which are
576 	 different can be looked up in the map.  The case in which
577 	 this section has been bypassed has addresses which correspond
578 	 to values I can find in the map.  */
579       *addendp -= sym->n_value;
580 #endif
581     }
582 
583 #if !defined(COFF_WITH_PE)
584   /* If the output symbol is common (in which case this must be a
585      relocatable link), we need to add in the final size of the
586      common symbol.  */
587   if (h != NULL && h->root.type == bfd_link_hash_common)
588     *addendp += h->root.u.c.size;
589 #endif
590 
591 #if defined(COFF_WITH_PE)
592   if (howto->pc_relative)
593     {
594       *addendp -= 4;
595 
596       /* If the symbol is defined, then the generic code is going to
597          add back the symbol value in order to cancel out an
598          adjustment it made to the addend.  However, we set the addend
599          to 0 at the start of this function.  We need to adjust here,
600          to avoid the adjustment the generic code will make.  FIXME:
601          This is getting a bit hackish.  */
602       if (sym != NULL && sym->n_scnum != 0)
603 	*addendp -= sym->n_value;
604     }
605 
606   if (rel->r_type == R_AMD64_IMAGEBASE
607       && (bfd_get_flavour (sec->output_section->owner) == bfd_target_coff_flavour))
608     *addendp -= pe_data (sec->output_section->owner)->pe_opthdr.ImageBase;
609 
610   if (rel->r_type == R_AMD64_SECREL)
611     {
612       bfd_vma osect_vma;
613 
614       if (h && (h->type == bfd_link_hash_defined || h->type == bfd_link_hash_defweak))
615 	osect_vma = h->root.u.def.section->output_section->vma;
616       else
617 	{
618 	  asection *sec;
619 	  int i;
620 
621 	  /* Sigh, the only way to get the section to offset against
622 	     is to find it the hard way.  */
623 	  for (sec = abfd->sections, i = 1; i < sym->n_scnum; i++)
624 	    sec = sec->next;
625 
626 	  osect_vma = sec->output_section->vma;
627 	}
628 
629       *addendp -= osect_vma;
630     }
631 #endif
632 
633   return howto;
634 }
635 
636 #define coff_bfd_reloc_type_lookup coff_amd64_reloc_type_lookup
637 #define coff_bfd_reloc_name_lookup coff_amd64_reloc_name_lookup
638 
639 static reloc_howto_type *
640 coff_amd64_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, bfd_reloc_code_real_type code)
641 {
642   switch (code)
643     {
644     case BFD_RELOC_RVA:
645       return howto_table + R_AMD64_IMAGEBASE;
646     case BFD_RELOC_32:
647       return howto_table + R_AMD64_DIR32;
648     case BFD_RELOC_64:
649       return howto_table + R_AMD64_DIR64;
650     case BFD_RELOC_64_PCREL:
651 #ifndef DONT_EXTEND_AMD64
652       return howto_table + R_AMD64_PCRQUAD;
653 #else
654       /* Fall through.  */
655 #endif
656     case BFD_RELOC_32_PCREL:
657       return howto_table + R_AMD64_PCRLONG;
658     case BFD_RELOC_X86_64_32S:
659       return howto_table + R_RELLONG;
660     case BFD_RELOC_16:
661       return howto_table + R_RELWORD;
662     case BFD_RELOC_16_PCREL:
663       return howto_table + R_PCRWORD;
664     case BFD_RELOC_8:
665       return howto_table + R_RELBYTE;
666     case BFD_RELOC_8_PCREL:
667       return howto_table + R_PCRBYTE;
668 #ifdef notyet
669 #if defined(COFF_WITH_PE)
670     case BFD_RELOC_32_SECREL:
671       return howto_table + R_AMD64_SECREL;
672 #endif
673 #endif
674     default:
675       BFD_FAIL ();
676       return 0;
677     }
678 }
679 
680 static reloc_howto_type *
681 coff_amd64_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
682 			      const char *r_name)
683 {
684   unsigned int i;
685 
686   for (i = 0; i < sizeof (howto_table) / sizeof (howto_table[0]); i++)
687     if (howto_table[i].name != NULL
688 	&& strcasecmp (howto_table[i].name, r_name) == 0)
689       return &howto_table[i];
690 
691   return NULL;
692 }
693 
694 #define coff_rtype_to_howto coff_amd64_rtype_to_howto
695 
696 #ifdef TARGET_UNDERSCORE
697 
698 /* If amd64 gcc uses underscores for symbol names, then it does not use
699    a leading dot for local labels, so if TARGET_UNDERSCORE is defined
700    we treat all symbols starting with L as local.  */
701 
702 static bfd_boolean
703 coff_amd64_is_local_label_name (bfd *abfd, const char *name)
704 {
705   if (name[0] == 'L')
706     return TRUE;
707 
708   return _bfd_coff_is_local_label_name (abfd, name);
709 }
710 
711 #define coff_bfd_is_local_label_name coff_amd64_is_local_label_name
712 
713 #endif /* TARGET_UNDERSCORE */
714 
715 #include "coffcode.h"
716 
717 #ifdef PE
718 #define amd64coff_object_p pe_bfd_object_p
719 #else
720 #define amd64coff_object_p coff_object_p
721 #endif
722 
723 const bfd_target
724 #ifdef TARGET_SYM
725   TARGET_SYM =
726 #else
727   x86_64coff_vec =
728 #endif
729 {
730 #ifdef TARGET_NAME
731   TARGET_NAME,
732 #else
733  "coff-x86-64",			/* Name.  */
734 #endif
735   bfd_target_coff_flavour,
736   BFD_ENDIAN_LITTLE,		/* Data byte order is little.  */
737   BFD_ENDIAN_LITTLE,		/* Header byte order is little.  */
738 
739   (HAS_RELOC | EXEC_P |		/* Object flags.  */
740    HAS_LINENO | HAS_DEBUG |
741    HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
742 
743   (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC /* Section flags.  */
744 #if defined(COFF_WITH_PE)
745    | SEC_LINK_ONCE | SEC_LINK_DUPLICATES | SEC_READONLY
746 #endif
747    | SEC_CODE | SEC_DATA),
748 
749 #ifdef TARGET_UNDERSCORE
750   TARGET_UNDERSCORE,		/* Leading underscore.  */
751 #else
752   0,				/* Leading underscore.  */
753 #endif
754   '/',				/* Ar_pad_char.  */
755   15,				/* Ar_max_namelen.  */
756 
757   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
758      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
759      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* Data.  */
760   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
761      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
762      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* Hdrs.  */
763 
764   /* Note that we allow an object file to be treated as a core file as well.  */
765   { _bfd_dummy_target, amd64coff_object_p, /* BFD_check_format.  */
766     bfd_generic_archive_p, amd64coff_object_p },
767   { bfd_false, coff_mkobject, _bfd_generic_mkarchive, /* bfd_set_format.  */
768     bfd_false },
769   { bfd_false, coff_write_object_contents, /* bfd_write_contents.  */
770    _bfd_write_archive_contents, bfd_false },
771 
772   BFD_JUMP_TABLE_GENERIC (coff),
773   BFD_JUMP_TABLE_COPY (coff),
774   BFD_JUMP_TABLE_CORE (_bfd_nocore),
775   BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
776   BFD_JUMP_TABLE_SYMBOLS (coff),
777   BFD_JUMP_TABLE_RELOCS (coff),
778   BFD_JUMP_TABLE_WRITE (coff),
779   BFD_JUMP_TABLE_LINK (coff),
780   BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
781 
782   NULL,
783 
784   COFF_SWAP_TABLE
785 };
786