xref: /openbsd-src/gnu/usr.bin/binutils/bfd/elf32-avr.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /* AVR-specific support for 32-bit ELF
2    Copyright (C) 1999, 2000 Free Software Foundation, Inc.
3    Contributed by Denis Chertykov <denisc@overta.ru>
4 
5 This file is part of BFD, the Binary File Descriptor library.
6 
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11 
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
20 
21 
22 #include "bfd.h"
23 #include "sysdep.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26 #include "elf/avr.h"
27 
28 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
29   PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
30 static void avr_info_to_howto_rela
31   PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
32 static asection *elf32_avr_gc_mark_hook
33   PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
34 	   struct elf_link_hash_entry *, Elf_Internal_Sym *));
35 static boolean elf32_avr_gc_sweep_hook
36   PARAMS ((bfd *, struct bfd_link_info *, asection *,
37 	   const Elf_Internal_Rela *));
38 static boolean elf32_avr_check_relocs
39   PARAMS ((bfd *, struct bfd_link_info *, asection *,
40 	   const Elf_Internal_Rela *));
41 static bfd_reloc_status_type avr_final_link_relocate
42   PARAMS ((reloc_howto_type *, bfd *, asection *, bfd_byte *,
43 	   Elf_Internal_Rela *, bfd_vma));
44 static boolean elf32_avr_relocate_section
45   PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
46 	   Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
47 static void bfd_elf_avr_final_write_processing PARAMS ((bfd *, boolean));
48 static boolean elf32_avr_object_p PARAMS ((bfd *));
49 
50 
51 /* Use RELA instead of REL */
52 #undef USE_REL
53 
54 static reloc_howto_type elf_avr_howto_table[] =
55 {
56   HOWTO (R_AVR_NONE,		/* type */
57 	 0,			/* rightshift */
58 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
59 	 32,			/* bitsize */
60 	 false,			/* pc_relative */
61 	 0,			/* bitpos */
62 	 complain_overflow_bitfield, /* complain_on_overflow */
63 	 bfd_elf_generic_reloc,	/* special_function */
64 	 "R_AVR_NONE",		/* name */
65 	 false,			/* partial_inplace */
66 	 0,			/* src_mask */
67 	 0,			/* dst_mask */
68 	 false),		/* pcrel_offset */
69 
70   HOWTO (R_AVR_32,		/* type */
71 	 0,			/* rightshift */
72 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
73 	 32,			/* bitsize */
74 	 false,			/* pc_relative */
75 	 0,			/* bitpos */
76 	 complain_overflow_bitfield, /* complain_on_overflow */
77 	 bfd_elf_generic_reloc,	/* special_function */
78 	 "R_AVR_32",		/* name */
79 	 false,			/* partial_inplace */
80 	 0xffffffff,		/* src_mask */
81 	 0xffffffff,		/* dst_mask */
82 	 false),		/* pcrel_offset */
83 
84   /* A 7 bit PC relative relocation.  */
85   HOWTO (R_AVR_7_PCREL,		/* type */
86 	 1,			/* rightshift */
87 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
88 	 7,			/* bitsize */
89 	 true,			/* pc_relative */
90 	 3,			/* bitpos */
91 	 complain_overflow_bitfield, /* complain_on_overflow */
92 	 bfd_elf_generic_reloc, /* special_function */
93 	 "R_AVR_7_PCREL",	/* name */
94 	 false,			/* partial_inplace */
95 	 0xffff,		/* src_mask */
96 	 0xffff,		/* dst_mask */
97 	 true),			/* pcrel_offset */
98 
99   /* A 13 bit PC relative relocation.  */
100   HOWTO (R_AVR_13_PCREL,	/* type */
101 	 1,			/* rightshift */
102 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
103 	 13,			/* bitsize */
104 	 true,			/* pc_relative */
105 	 0,			/* bitpos */
106 	 complain_overflow_bitfield, /* complain_on_overflow */
107 	 bfd_elf_generic_reloc, /* special_function */
108 	 "R_AVR_13_PCREL",	/* name */
109 	 false,			/* partial_inplace */
110 	 0xfff,			/* src_mask */
111 	 0xfff,			/* dst_mask */
112 	 true),			/* pcrel_offset */
113 
114   /* A 16 bit absolute relocation.  */
115   HOWTO (R_AVR_16,		/* type */
116 	 0,			/* rightshift */
117 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
118 	 16,			/* bitsize */
119 	 false,			/* pc_relative */
120 	 0,			/* bitpos */
121 	 complain_overflow_dont, /* complain_on_overflow */
122 	 bfd_elf_generic_reloc,	/* special_function */
123 	 "R_AVR_16",		/* name */
124 	 false,			/* partial_inplace */
125 	 0xffff,		/* src_mask */
126 	 0xffff,		/* dst_mask */
127 	 false),		/* pcrel_offset */
128 
129   /* A 16 bit absolute relocation for command address.  */
130   HOWTO (R_AVR_16_PM,		/* type */
131 	 1,			/* rightshift */
132 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
133 	 16,			/* bitsize */
134 	 false,			/* pc_relative */
135 	 0,			/* bitpos */
136 	 complain_overflow_bitfield, /* complain_on_overflow */
137 	 bfd_elf_generic_reloc,	/* special_function */
138 	 "R_AVR_16_PM",		/* name */
139 	 false,			/* partial_inplace */
140 	 0xffff,		/* src_mask */
141 	 0xffff,		/* dst_mask */
142 	 false),		/* pcrel_offset */
143   /* A low 8 bit absolute relocation of 16 bit address.
144      For LDI command.  */
145   HOWTO (R_AVR_LO8_LDI,		/* type */
146 	 0,			/* rightshift */
147 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
148 	 8,			/* bitsize */
149 	 false,			/* pc_relative */
150 	 0,			/* bitpos */
151 	 complain_overflow_dont, /* complain_on_overflow */
152 	 bfd_elf_generic_reloc,	/* special_function */
153 	 "R_AVR_LO8_LDI",	/* name */
154 	 false,			/* partial_inplace */
155 	 0xffff,		/* src_mask */
156 	 0xffff,		/* dst_mask */
157 	 false),		/* pcrel_offset */
158   /* A high 8 bit absolute relocation of 16 bit address.
159      For LDI command.  */
160   HOWTO (R_AVR_HI8_LDI,		/* type */
161 	 8,			/* rightshift */
162 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
163 	 8,			/* bitsize */
164 	 false,			/* pc_relative */
165 	 0,			/* bitpos */
166 	 complain_overflow_dont, /* complain_on_overflow */
167 	 bfd_elf_generic_reloc,	/* special_function */
168 	 "R_AVR_HI8_LDI",	/* name */
169 	 false,			/* partial_inplace */
170 	 0xffff,		/* src_mask */
171 	 0xffff,		/* dst_mask */
172 	 false),		/* pcrel_offset */
173   /* A high 6 bit absolute relocation of 22 bit address.
174      For LDI command.  */
175   HOWTO (R_AVR_HH8_LDI,		/* type */
176 	 16,			/* rightshift */
177 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
178 	 8,			/* bitsize */
179 	 false,			/* pc_relative */
180 	 0,			/* bitpos */
181 	 complain_overflow_dont, /* complain_on_overflow */
182 	 bfd_elf_generic_reloc,	/* special_function */
183 	 "R_AVR_HH8_LDI",	/* name */
184 	 false,			/* partial_inplace */
185 	 0xffff,		/* src_mask */
186 	 0xffff,		/* dst_mask */
187 	 false),		/* pcrel_offset */
188   /* A negative low 8 bit absolute relocation of 16 bit address.
189      For LDI command.  */
190   HOWTO (R_AVR_LO8_LDI_NEG,	/* type */
191 	 0,			/* rightshift */
192 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
193 	 8,			/* bitsize */
194 	 false,			/* pc_relative */
195 	 0,			/* bitpos */
196 	 complain_overflow_dont, /* complain_on_overflow */
197 	 bfd_elf_generic_reloc,	/* special_function */
198 	 "R_AVR_LO8_LDI_NEG",	/* name */
199 	 false,			/* partial_inplace */
200 	 0xffff,		/* src_mask */
201 	 0xffff,		/* dst_mask */
202 	 false),		/* pcrel_offset */
203   /* A hegative high 8 bit absolute relocation of 16 bit address.
204      For LDI command.  */
205   HOWTO (R_AVR_HI8_LDI_NEG,	/* type */
206 	 8,			/* rightshift */
207 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
208 	 8,			/* bitsize */
209 	 false,			/* pc_relative */
210 	 0,			/* bitpos */
211 	 complain_overflow_dont, /* complain_on_overflow */
212 	 bfd_elf_generic_reloc,	/* special_function */
213 	 "R_AVR_HI8_LDI_NEG",	/* name */
214 	 false,			/* partial_inplace */
215 	 0xffff,		/* src_mask */
216 	 0xffff,		/* dst_mask */
217 	 false),		/* pcrel_offset */
218   /* A hegative high 6 bit absolute relocation of 22 bit address.
219      For LDI command.  */
220   HOWTO (R_AVR_HH8_LDI_NEG,	/* type */
221 	 16,			/* rightshift */
222 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
223 	 8,			/* bitsize */
224 	 false,			/* pc_relative */
225 	 0,			/* bitpos */
226 	 complain_overflow_dont, /* complain_on_overflow */
227 	 bfd_elf_generic_reloc,	/* special_function */
228 	 "R_AVR_HH8_LDI_NEG",	/* name */
229 	 false,			/* partial_inplace */
230 	 0xffff,		/* src_mask */
231 	 0xffff,		/* dst_mask */
232 	 false),		/* pcrel_offset */
233   /* A low 8 bit absolute relocation of 24 bit program memory address.
234      For LDI command.  */
235   HOWTO (R_AVR_LO8_LDI_PM,	/* type */
236 	 1,			/* rightshift */
237 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
238 	 8,			/* bitsize */
239 	 false,			/* pc_relative */
240 	 0,			/* bitpos */
241 	 complain_overflow_dont, /* complain_on_overflow */
242 	 bfd_elf_generic_reloc,	/* special_function */
243 	 "R_AVR_LO8_LDI_PM",	/* name */
244 	 false,			/* partial_inplace */
245 	 0xffff,		/* src_mask */
246 	 0xffff,		/* dst_mask */
247 	 false),		/* pcrel_offset */
248   /* A high 8 bit absolute relocation of 16 bit program memory address.
249      For LDI command.  */
250   HOWTO (R_AVR_HI8_LDI_PM,	/* type */
251 	 9,			/* rightshift */
252 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
253 	 8,			/* bitsize */
254 	 false,			/* pc_relative */
255 	 0,			/* bitpos */
256 	 complain_overflow_dont, /* complain_on_overflow */
257 	 bfd_elf_generic_reloc,	/* special_function */
258 	 "R_AVR_HI8_LDI_PM",	/* name */
259 	 false,			/* partial_inplace */
260 	 0xffff,		/* src_mask */
261 	 0xffff,		/* dst_mask */
262 	 false),		/* pcrel_offset */
263   /* A high 8 bit absolute relocation of 24 bit program memory address.
264      For LDI command.  */
265   HOWTO (R_AVR_HH8_LDI_PM,	/* type */
266 	 17,			/* rightshift */
267 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
268 	 8,			/* bitsize */
269 	 false,			/* pc_relative */
270 	 0,			/* bitpos */
271 	 complain_overflow_dont, /* complain_on_overflow */
272 	 bfd_elf_generic_reloc,	/* special_function */
273 	 "R_AVR_HH8_LDI_PM",	/* name */
274 	 false,			/* partial_inplace */
275 	 0xffff,		/* src_mask */
276 	 0xffff,		/* dst_mask */
277 	 false),		/* pcrel_offset */
278   /* A low 8 bit absolute relocation of a negative 24 bit
279      program memory address.  For LDI command.  */
280   HOWTO (R_AVR_LO8_LDI_PM_NEG,	/* type */
281 	 1,			/* rightshift */
282 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
283 	 8,			/* bitsize */
284 	 false,			/* pc_relative */
285 	 0,			/* bitpos */
286 	 complain_overflow_dont, /* complain_on_overflow */
287 	 bfd_elf_generic_reloc,	/* special_function */
288 	 "R_AVR_LO8_LDI_PM_NEG", /* name */
289 	 false,			/* partial_inplace */
290 	 0xffff,		/* src_mask */
291 	 0xffff,		/* dst_mask */
292 	 false),		/* pcrel_offset */
293   /* A high 8 bit absolute relocation of a negative 16 bit
294      program memory address.  For LDI command.  */
295   HOWTO (R_AVR_HI8_LDI_PM_NEG,	/* type */
296 	 9,			/* rightshift */
297 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
298 	 8,			/* bitsize */
299 	 false,			/* pc_relative */
300 	 0,			/* bitpos */
301 	 complain_overflow_dont, /* complain_on_overflow */
302 	 bfd_elf_generic_reloc,	/* special_function */
303 	 "R_AVR_HI8_LDI_PM_NEG", /* name */
304 	 false,			/* partial_inplace */
305 	 0xffff,		/* src_mask */
306 	 0xffff,		/* dst_mask */
307 	 false),		/* pcrel_offset */
308   /* A high 8 bit absolute relocation of a negative 24 bit
309      program memory address.  For LDI command.  */
310   HOWTO (R_AVR_HH8_LDI_PM_NEG,	/* type */
311 	 17,			/* rightshift */
312 	 1,			/* size (0 = byte, 1 = short, 2 = long) */
313 	 8,			/* bitsize */
314 	 false,			/* pc_relative */
315 	 0,			/* bitpos */
316 	 complain_overflow_dont, /* complain_on_overflow */
317 	 bfd_elf_generic_reloc,	/* special_function */
318 	 "R_AVR_HH8_LDI_PM_NEG", /* name */
319 	 false,			/* partial_inplace */
320 	 0xffff,		/* src_mask */
321 	 0xffff,		/* dst_mask */
322 	 false),		/* pcrel_offset */
323   /* Relocation for CALL command in ATmega.  */
324   HOWTO (R_AVR_CALL,		/* type */
325 	 1,			/* rightshift */
326 	 2,			/* size (0 = byte, 1 = short, 2 = long) */
327 	 23,			/* bitsize */
328 	 false,			/* pc_relative */
329 	 0,			/* bitpos */
330 	 complain_overflow_dont, /* complain_on_overflow */
331 	 bfd_elf_generic_reloc,	/* special_function */
332 	 "R_AVR_CALL",		/* name */
333 	 false,			/* partial_inplace */
334 	 0xffffffff,		/* src_mask */
335 	 0xffffffff,		/* dst_mask */
336 	 false)			/* pcrel_offset */
337 };
338 
339 /* Map BFD reloc types to AVR ELF reloc types.  */
340 
341 struct avr_reloc_map
342 {
343   bfd_reloc_code_real_type bfd_reloc_val;
344   unsigned int elf_reloc_val;
345 };
346 
347  static const struct avr_reloc_map avr_reloc_map[] =
348 {
349   { BFD_RELOC_NONE,                 R_AVR_NONE },
350   { BFD_RELOC_32,                   R_AVR_32 },
351   { BFD_RELOC_AVR_7_PCREL,          R_AVR_7_PCREL },
352   { BFD_RELOC_AVR_13_PCREL,         R_AVR_13_PCREL },
353   { BFD_RELOC_16,                   R_AVR_16 },
354   { BFD_RELOC_AVR_16_PM,            R_AVR_16_PM },
355   { BFD_RELOC_AVR_LO8_LDI,          R_AVR_LO8_LDI},
356   { BFD_RELOC_AVR_HI8_LDI,          R_AVR_HI8_LDI },
357   { BFD_RELOC_AVR_HH8_LDI,          R_AVR_HH8_LDI },
358   { BFD_RELOC_AVR_LO8_LDI_NEG,      R_AVR_LO8_LDI_NEG },
359   { BFD_RELOC_AVR_HI8_LDI_NEG,      R_AVR_HI8_LDI_NEG },
360   { BFD_RELOC_AVR_HH8_LDI_NEG,      R_AVR_HH8_LDI_NEG },
361   { BFD_RELOC_AVR_LO8_LDI_PM,       R_AVR_LO8_LDI_PM },
362   { BFD_RELOC_AVR_HI8_LDI_PM,       R_AVR_HI8_LDI_PM },
363   { BFD_RELOC_AVR_HH8_LDI_PM,       R_AVR_HH8_LDI_PM },
364   { BFD_RELOC_AVR_LO8_LDI_PM_NEG,   R_AVR_LO8_LDI_PM_NEG },
365   { BFD_RELOC_AVR_HI8_LDI_PM_NEG,   R_AVR_HI8_LDI_PM_NEG },
366   { BFD_RELOC_AVR_HH8_LDI_PM_NEG,   R_AVR_HH8_LDI_PM_NEG },
367   { BFD_RELOC_AVR_CALL,             R_AVR_CALL }
368 };
369 
370 static reloc_howto_type *
371 bfd_elf32_bfd_reloc_type_lookup (abfd, code)
372      bfd *abfd;
373      bfd_reloc_code_real_type code;
374 {
375   unsigned int i;
376 
377   for (i = 0;
378        i < sizeof (avr_reloc_map) / sizeof (struct avr_reloc_map);
379        i++)
380     {
381       if (avr_reloc_map[i].bfd_reloc_val == code)
382 	return &elf_avr_howto_table[avr_reloc_map[i].elf_reloc_val];
383     }
384 
385   return NULL;
386 }
387 
388 /* Set the howto pointer for an AVR ELF reloc.  */
389 
390 static void
391 avr_info_to_howto_rela (abfd, cache_ptr, dst)
392      bfd *abfd;
393      arelent *cache_ptr;
394      Elf32_Internal_Rela *dst;
395 {
396   unsigned int r_type;
397 
398   r_type = ELF32_R_TYPE (dst->r_info);
399   BFD_ASSERT (r_type < (unsigned int) R_AVR_max);
400   cache_ptr->howto = &elf_avr_howto_table[r_type];
401 }
402 
403 static asection *
404 elf32_avr_gc_mark_hook (abfd, info, rel, h, sym)
405      bfd *abfd;
406      struct bfd_link_info *info;
407      Elf_Internal_Rela *rel;
408      struct elf_link_hash_entry *h;
409      Elf_Internal_Sym *sym;
410 {
411   if (h != NULL)
412     {
413       switch (ELF32_R_TYPE (rel->r_info))
414 	{
415 	default:
416 	  switch (h->root.type)
417 	    {
418 	    case bfd_link_hash_defined:
419 	    case bfd_link_hash_defweak:
420 	      return h->root.u.def.section;
421 
422 	    case bfd_link_hash_common:
423 	      return h->root.u.c.p->section;
424 
425 	    default:
426 	      break;
427 	    }
428 	}
429     }
430   else
431     {
432       if (!(elf_bad_symtab (abfd)
433 	    && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
434 	  && !((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
435 	       && sym->st_shndx != SHN_COMMON))
436 	{
437 	  return bfd_section_from_elf_index (abfd, sym->st_shndx);
438 	}
439     }
440   return NULL;
441 }
442 
443 static boolean
444 elf32_avr_gc_sweep_hook (abfd, info, sec, relocs)
445      bfd *abfd;
446      struct bfd_link_info *info;
447      asection *sec;
448      const Elf_Internal_Rela *relocs;
449 {
450   /* We don't use got and plt entries for avr.  */
451   return true;
452 }
453 
454 /* Look through the relocs for a section during the first phase.
455    Since we don't do .gots or .plts, we just need to consider the
456    virtual table relocs for gc.  */
457 
458 static boolean
459 elf32_avr_check_relocs (abfd, info, sec, relocs)
460      bfd *abfd;
461      struct bfd_link_info *info;
462      asection *sec;
463      const Elf_Internal_Rela *relocs;
464 {
465   Elf_Internal_Shdr *symtab_hdr;
466   struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
467   const Elf_Internal_Rela *rel;
468   const Elf_Internal_Rela *rel_end;
469 
470   if (info->relocateable)
471     return true;
472 
473   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
474   sym_hashes = elf_sym_hashes (abfd);
475   sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof(Elf32_External_Sym);
476   if (!elf_bad_symtab (abfd))
477     sym_hashes_end -= symtab_hdr->sh_info;
478 
479   rel_end = relocs + sec->reloc_count;
480   for (rel = relocs; rel < rel_end; rel++)
481     {
482       struct elf_link_hash_entry *h;
483       unsigned long r_symndx;
484 
485       r_symndx = ELF32_R_SYM (rel->r_info);
486       if (r_symndx < symtab_hdr->sh_info)
487         h = NULL;
488       else
489         h = sym_hashes[r_symndx - symtab_hdr->sh_info];
490     }
491 
492   return true;
493 }
494 
495 /* Perform a single relocation.  By default we use the standard BFD
496    routines, but a few relocs, we have to do them ourselves.  */
497 
498 static bfd_reloc_status_type
499 avr_final_link_relocate (howto, input_bfd, input_section,
500 			 contents, rel, relocation)
501      reloc_howto_type *  howto;
502      bfd *               input_bfd;
503      asection *          input_section;
504      bfd_byte *          contents;
505      Elf_Internal_Rela * rel;
506      bfd_vma             relocation;
507 {
508   bfd_reloc_status_type r = bfd_reloc_ok;
509   bfd_vma               x;
510   bfd_signed_vma	srel;
511 
512   switch (howto->type)
513     {
514     case R_AVR_7_PCREL:
515       contents += rel->r_offset;
516       srel = (bfd_signed_vma) relocation;
517       srel += rel->r_addend;
518       srel -= rel->r_offset;
519       srel -= 2;	/* Branch instructions add 2 to the PC... */
520       srel -= (input_section->output_section->vma +
521 	       input_section->output_offset);
522 
523       if (srel & 1)
524 	return bfd_reloc_outofrange;
525       if (srel > ((1 << 7) - 1) || (srel < - (1 << 7)))
526 	return bfd_reloc_overflow;
527       x = bfd_get_16 (input_bfd, contents);
528       x = (x & 0xfc07) | (((srel >> 1) << 3) & 0x3f8);
529       bfd_put_16 (input_bfd, x, contents);
530       break;
531 
532     case R_AVR_13_PCREL:
533       contents   += rel->r_offset;
534       srel = (bfd_signed_vma) relocation;
535       srel += rel->r_addend;
536       srel -= rel->r_offset;
537       srel -= 2;	/* Branch instructions add 2 to the PC... */
538       srel -= (input_section->output_section->vma +
539 	       input_section->output_offset);
540 
541       if (srel & 1)
542 	return bfd_reloc_outofrange;
543 
544       /* AVR addresses commands as words.  */
545       srel >>= 1;
546 
547       /* Check for overflow.  */
548       if (srel < -2048 || srel > 2047)
549 	{
550 	  /* Apply WRAPAROUND if possible.  */
551 	  if (bfd_get_mach (input_bfd) == bfd_mach_avr2)
552 	    {
553 	      if (srel > 2047)
554 		srel -= 4096;
555 	      else
556 		srel += 4096;
557 	    }
558 	  else
559 	    return bfd_reloc_overflow;
560 	}
561 
562       x = bfd_get_16 (input_bfd, contents);
563       x = (x & 0xf000) | (srel & 0xfff);
564       bfd_put_16 (input_bfd, x, contents);
565       break;
566 
567     case R_AVR_LO8_LDI:
568       contents += rel->r_offset;
569       srel = (bfd_signed_vma) relocation + rel->r_addend;
570       x = bfd_get_16 (input_bfd, contents);
571       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
572       bfd_put_16 (input_bfd, x, contents);
573       break;
574 
575     case R_AVR_HI8_LDI:
576       contents += rel->r_offset;
577       srel = (bfd_signed_vma) relocation + rel->r_addend;
578       srel = (srel >> 8) & 0xff;
579       x = bfd_get_16 (input_bfd, contents);
580       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
581       bfd_put_16 (input_bfd, x, contents);
582       break;
583 
584     case R_AVR_HH8_LDI:
585       contents += rel->r_offset;
586       srel = (bfd_signed_vma) relocation + rel->r_addend;
587       srel = (srel >> 16) & 0xff;
588       x = bfd_get_16 (input_bfd, contents);
589       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
590       bfd_put_16 (input_bfd, x, contents);
591       break;
592 
593     case R_AVR_LO8_LDI_NEG:
594       contents += rel->r_offset;
595       srel = (bfd_signed_vma) relocation + rel->r_addend;
596       srel = -srel;
597       x = bfd_get_16 (input_bfd, contents);
598       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
599       bfd_put_16 (input_bfd, x, contents);
600       break;
601 
602     case R_AVR_HI8_LDI_NEG:
603       contents += rel->r_offset;
604       srel = (bfd_signed_vma) relocation + rel->r_addend;
605       srel = -srel;
606       srel = (srel >> 8) & 0xff;
607       x = bfd_get_16 (input_bfd, contents);
608       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
609       bfd_put_16 (input_bfd, x, contents);
610       break;
611 
612     case R_AVR_HH8_LDI_NEG:
613       contents += rel->r_offset;
614       srel = (bfd_signed_vma) relocation + rel->r_addend;
615       srel = -srel;
616       srel = (srel >> 16) & 0xff;
617       x = bfd_get_16 (input_bfd, contents);
618       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
619       bfd_put_16 (input_bfd, x, contents);
620       break;
621 
622     case R_AVR_LO8_LDI_PM:
623       contents += rel->r_offset;
624       srel = (bfd_signed_vma) relocation + rel->r_addend;
625       if (srel & 1)
626 	return bfd_reloc_outofrange;
627       srel = srel >> 1;
628       x = bfd_get_16 (input_bfd, contents);
629       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
630       bfd_put_16 (input_bfd, x, contents);
631       break;
632 
633     case R_AVR_HI8_LDI_PM:
634       contents += rel->r_offset;
635       srel = (bfd_signed_vma) relocation + rel->r_addend;
636       if (srel & 1)
637 	return bfd_reloc_outofrange;
638       srel = srel >> 1;
639       srel = (srel >> 8) & 0xff;
640       x = bfd_get_16 (input_bfd, contents);
641       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
642       bfd_put_16 (input_bfd, x, contents);
643       break;
644 
645     case R_AVR_HH8_LDI_PM:
646       contents += rel->r_offset;
647       srel = (bfd_signed_vma) relocation + rel->r_addend;
648       if (srel & 1)
649 	return bfd_reloc_outofrange;
650       srel = srel >> 1;
651       srel = (srel >> 16) & 0xff;
652       x = bfd_get_16 (input_bfd, contents);
653       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
654       bfd_put_16 (input_bfd, x, contents);
655       break;
656 
657     case R_AVR_LO8_LDI_PM_NEG:
658       contents += rel->r_offset;
659       srel = (bfd_signed_vma) relocation + rel->r_addend;
660       srel = -srel;
661       if (srel & 1)
662 	return bfd_reloc_outofrange;
663       srel = srel >> 1;
664       x = bfd_get_16 (input_bfd, contents);
665       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
666       bfd_put_16 (input_bfd, x, contents);
667       break;
668 
669     case R_AVR_HI8_LDI_PM_NEG:
670       contents += rel->r_offset;
671       srel = (bfd_signed_vma) relocation + rel->r_addend;
672       srel = -srel;
673       if (srel & 1)
674 	return bfd_reloc_outofrange;
675       srel = srel >> 1;
676       srel = (srel >> 8) & 0xff;
677       x = bfd_get_16 (input_bfd, contents);
678       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
679       bfd_put_16 (input_bfd, x, contents);
680       break;
681 
682     case R_AVR_HH8_LDI_PM_NEG:
683       contents += rel->r_offset;
684       srel = (bfd_signed_vma) relocation + rel->r_addend;
685       srel = -srel;
686       if (srel & 1)
687 	return bfd_reloc_outofrange;
688       srel = srel >> 1;
689       srel = (srel >> 16) & 0xff;
690       x = bfd_get_16 (input_bfd, contents);
691       x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
692       bfd_put_16 (input_bfd, x, contents);
693       break;
694 
695     case R_AVR_CALL:
696       contents += rel->r_offset;
697       srel = (bfd_signed_vma) relocation + rel->r_addend;
698       if (srel & 1)
699 	return bfd_reloc_outofrange;
700       srel = srel >> 1;
701       x = bfd_get_16 (input_bfd, contents);
702       x |= ((srel & 0x10000) | ((srel << 3) & 0x1f00000)) >> 16;
703       bfd_put_16 (input_bfd, x, contents);
704       bfd_put_16 (input_bfd, srel & 0xffff, contents+2);
705       break;
706 
707     default:
708       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
709 				    contents, rel->r_offset,
710 				    relocation, rel->r_addend);
711     }
712 
713   return r;
714 }
715 
716 /* Relocate an AVR ELF section.  */
717 static boolean
718 elf32_avr_relocate_section (output_bfd, info, input_bfd, input_section,
719 			    contents, relocs, local_syms, local_sections)
720      bfd *output_bfd;
721      struct bfd_link_info *info;
722      bfd *input_bfd;
723      asection *input_section;
724      bfd_byte *contents;
725      Elf_Internal_Rela *relocs;
726      Elf_Internal_Sym *local_syms;
727      asection **local_sections;
728 {
729   Elf_Internal_Shdr *           symtab_hdr;
730   struct elf_link_hash_entry ** sym_hashes;
731   Elf_Internal_Rela *           rel;
732   Elf_Internal_Rela *           relend;
733 
734   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
735   sym_hashes = elf_sym_hashes (input_bfd);
736   relend     = relocs + input_section->reloc_count;
737 
738   for (rel = relocs; rel < relend; rel ++)
739     {
740       reloc_howto_type *           howto;
741       unsigned long                r_symndx;
742       Elf_Internal_Sym *           sym;
743       asection *                   sec;
744       struct elf_link_hash_entry * h;
745       bfd_vma                      relocation;
746       bfd_reloc_status_type        r;
747       const char *                 name = NULL;
748       int                          r_type;
749 
750       r_type = ELF32_R_TYPE (rel->r_info);
751       r_symndx = ELF32_R_SYM (rel->r_info);
752 
753       if (info->relocateable)
754 	{
755 	  /* This is a relocateable link.  We don't have to change
756              anything, unless the reloc is against a section symbol,
757              in which case we have to adjust according to where the
758              section symbol winds up in the output section.  */
759 	  if (r_symndx < symtab_hdr->sh_info)
760 	    {
761 	      sym = local_syms + r_symndx;
762 
763 	      if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
764 		{
765 		  sec = local_sections [r_symndx];
766 		  rel->r_addend += sec->output_offset + sym->st_value;
767 		}
768 	    }
769 
770 	  continue;
771 	}
772 
773       /* This is a final link.  */
774       howto  = elf_avr_howto_table + ELF32_R_TYPE (rel->r_info);
775       h      = NULL;
776       sym    = NULL;
777       sec    = NULL;
778 
779       if (r_symndx < symtab_hdr->sh_info)
780 	{
781 	  sym = local_syms + r_symndx;
782 	  sec = local_sections [r_symndx];
783 	  relocation = (sec->output_section->vma
784 			+ sec->output_offset
785 			+ sym->st_value);
786 
787 	  name = bfd_elf_string_from_elf_section
788 	    (input_bfd, symtab_hdr->sh_link, sym->st_name);
789 	  name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
790 	}
791       else
792 	{
793 	  h = sym_hashes [r_symndx - symtab_hdr->sh_info];
794 
795 	  while (h->root.type == bfd_link_hash_indirect
796 		 || h->root.type == bfd_link_hash_warning)
797 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
798 
799 	  name = h->root.root.string;
800 
801 	  if (h->root.type == bfd_link_hash_defined
802 	      || h->root.type == bfd_link_hash_defweak)
803 	    {
804 	      sec = h->root.u.def.section;
805 	      relocation = (h->root.u.def.value
806 			    + sec->output_section->vma
807 			    + sec->output_offset);
808 	    }
809 	  else if (h->root.type == bfd_link_hash_undefweak)
810 	    {
811 	      relocation = 0;
812 	    }
813 	  else
814 	    {
815 	      if (! ((*info->callbacks->undefined_symbol)
816 		     (info, h->root.root.string, input_bfd,
817 		      input_section, rel->r_offset, true)))
818 		return false;
819 	      relocation = 0;
820 	    }
821 	}
822 
823       r = avr_final_link_relocate (howto, input_bfd, input_section,
824 				   contents, rel, relocation);
825 
826       if (r != bfd_reloc_ok)
827 	{
828 	  const char * msg = (const char *) NULL;
829 
830 	  switch (r)
831 	    {
832 	    case bfd_reloc_overflow:
833 	      r = info->callbacks->reloc_overflow
834 		(info, name, howto->name, (bfd_vma) 0,
835 		 input_bfd, input_section, rel->r_offset);
836 	      break;
837 
838 	    case bfd_reloc_undefined:
839 	      r = info->callbacks->undefined_symbol
840 		(info, name, input_bfd, input_section, rel->r_offset, true);
841 	      break;
842 
843 	    case bfd_reloc_outofrange:
844 	      msg = _("internal error: out of range error");
845 	      break;
846 
847 	    case bfd_reloc_notsupported:
848 	      msg = _("internal error: unsupported relocation error");
849 	      break;
850 
851 	    case bfd_reloc_dangerous:
852 	      msg = _("internal error: dangerous relocation");
853 	      break;
854 
855 	    default:
856 	      msg = _("internal error: unknown error");
857 	      break;
858 	    }
859 
860 	  if (msg)
861 	    r = info->callbacks->warning
862 	      (info, msg, name, input_bfd, input_section, rel->r_offset);
863 
864 	  if (! r)
865 	    return false;
866 	}
867     }
868 
869   return true;
870 }
871 
872 /* The final processing done just before writing out a AVR ELF object
873    file.  This gets the AVR architecture right based on the machine
874    number.  */
875 
876 static void
877 bfd_elf_avr_final_write_processing (abfd, linker)
878      bfd *abfd;
879      boolean linker ATTRIBUTE_UNUSED;
880 {
881   unsigned long val;
882 
883   switch (bfd_get_mach (abfd))
884     {
885     default:
886     case bfd_mach_avr2:
887       val = E_AVR_MACH_AVR2;
888       break;
889 
890     case bfd_mach_avr1:
891       val = E_AVR_MACH_AVR1;
892       break;
893 
894     case bfd_mach_avr3:
895       val = E_AVR_MACH_AVR3;
896       break;
897 
898     case bfd_mach_avr4:
899       val = E_AVR_MACH_AVR4;
900       break;
901 
902     }
903 
904   elf_elfheader (abfd)->e_machine = EM_AVR;
905   elf_elfheader (abfd)->e_flags &= ~ EF_AVR_MACH;
906   elf_elfheader (abfd)->e_flags |= val;
907 }
908 
909 /* Set the right machine number.  */
910 
911 static boolean
912 elf32_avr_object_p (abfd)
913      bfd *abfd;
914 {
915   int e_set = bfd_mach_avr2;
916   if (elf_elfheader (abfd)->e_machine == EM_AVR)
917     {
918       int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
919       switch (e_mach)
920 	{
921 	default:
922 	case E_AVR_MACH_AVR2:
923 	  e_set = bfd_mach_avr2;
924 	  break;
925 
926 	case E_AVR_MACH_AVR1:
927 	  e_set = bfd_mach_avr1;
928 	  break;
929 
930 	case E_AVR_MACH_AVR3:
931 	  e_set = bfd_mach_avr3;
932 	  break;
933 
934 	case E_AVR_MACH_AVR4:
935 	  e_set = bfd_mach_avr4;
936 	  break;
937 	}
938     }
939   return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
940 				    e_set);
941 }
942 
943 
944 #define ELF_ARCH		bfd_arch_avr
945 #define ELF_MACHINE_CODE	EM_AVR
946 #define ELF_MAXPAGESIZE		1
947 
948 #define TARGET_LITTLE_SYM       bfd_elf32_avr_vec
949 #define TARGET_LITTLE_NAME	"elf32-avr"
950 
951 #define elf_info_to_howto	             avr_info_to_howto_rela
952 #define elf_info_to_howto_rel	             NULL
953 #define elf_backend_relocate_section         elf32_avr_relocate_section
954 #define elf_backend_gc_mark_hook             elf32_avr_gc_mark_hook
955 #define elf_backend_gc_sweep_hook            elf32_avr_gc_sweep_hook
956 #define elf_backend_check_relocs             elf32_avr_check_relocs
957 #define elf_backend_can_gc_sections          1
958 #define elf_backend_final_write_processing \
959 					bfd_elf_avr_final_write_processing
960 #define elf_backend_object_p		elf32_avr_object_p
961 
962 
963 #include "elf32-target.h"
964