PR ld/12161
[binutils.git] / bfd / elf32-avr.c
bloba7f92174136773dbe88b67be0eb649fc5e057c4f
1 /* AVR-specific support for 32-bit ELF
2 Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
3 2010, 2011 Free Software Foundation, Inc.
4 Contributed by Denis Chertykov <denisc@overta.ru>
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor,
21 Boston, MA 02110-1301, USA. */
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27 #include "elf/avr.h"
28 #include "elf32-avr.h"
30 /* Enable debugging printout at stdout with this variable. */
31 static bfd_boolean debug_relax = FALSE;
33 /* Enable debugging printout at stdout with this variable. */
34 static bfd_boolean debug_stubs = FALSE;
36 /* Hash table initialization and handling. Code is taken from the hppa port
37 and adapted to the needs of AVR. */
39 /* We use two hash tables to hold information for linking avr objects.
41 The first is the elf32_avr_link_hash_table which is derived from the
42 stanard ELF linker hash table. We use this as a place to attach the other
43 hash table and some static information.
45 The second is the stub hash table which is derived from the base BFD
46 hash table. The stub hash table holds the information on the linker
47 stubs. */
49 struct elf32_avr_stub_hash_entry
51 /* Base hash table entry structure. */
52 struct bfd_hash_entry bh_root;
54 /* Offset within stub_sec of the beginning of this stub. */
55 bfd_vma stub_offset;
57 /* Given the symbol's value and its section we can determine its final
58 value when building the stubs (so the stub knows where to jump). */
59 bfd_vma target_value;
61 /* This way we could mark stubs to be no longer necessary. */
62 bfd_boolean is_actually_needed;
65 struct elf32_avr_link_hash_table
67 /* The main hash table. */
68 struct elf_link_hash_table etab;
70 /* The stub hash table. */
71 struct bfd_hash_table bstab;
73 bfd_boolean no_stubs;
75 /* Linker stub bfd. */
76 bfd *stub_bfd;
78 /* The stub section. */
79 asection *stub_sec;
81 /* Usually 0, unless we are generating code for a bootloader. Will
82 be initialized by elf32_avr_size_stubs to the vma offset of the
83 output section associated with the stub section. */
84 bfd_vma vector_base;
86 /* Assorted information used by elf32_avr_size_stubs. */
87 unsigned int bfd_count;
88 int top_index;
89 asection ** input_list;
90 Elf_Internal_Sym ** all_local_syms;
92 /* Tables for mapping vma beyond the 128k boundary to the address of the
93 corresponding stub. (AMT)
94 "amt_max_entry_cnt" reflects the number of entries that memory is allocated
95 for in the "amt_stub_offsets" and "amt_destination_addr" arrays.
96 "amt_entry_cnt" informs how many of these entries actually contain
97 useful data. */
98 unsigned int amt_entry_cnt;
99 unsigned int amt_max_entry_cnt;
100 bfd_vma * amt_stub_offsets;
101 bfd_vma * amt_destination_addr;
104 /* Various hash macros and functions. */
105 #define avr_link_hash_table(p) \
106 /* PR 3874: Check that we have an AVR style hash table before using it. */\
107 (elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) \
108 == AVR_ELF_DATA ? ((struct elf32_avr_link_hash_table *) ((p)->hash)) : NULL)
110 #define avr_stub_hash_entry(ent) \
111 ((struct elf32_avr_stub_hash_entry *)(ent))
113 #define avr_stub_hash_lookup(table, string, create, copy) \
114 ((struct elf32_avr_stub_hash_entry *) \
115 bfd_hash_lookup ((table), (string), (create), (copy)))
117 static reloc_howto_type elf_avr_howto_table[] =
119 HOWTO (R_AVR_NONE, /* type */
120 0, /* rightshift */
121 2, /* size (0 = byte, 1 = short, 2 = long) */
122 32, /* bitsize */
123 FALSE, /* pc_relative */
124 0, /* bitpos */
125 complain_overflow_bitfield, /* complain_on_overflow */
126 bfd_elf_generic_reloc, /* special_function */
127 "R_AVR_NONE", /* name */
128 FALSE, /* partial_inplace */
129 0, /* src_mask */
130 0, /* dst_mask */
131 FALSE), /* pcrel_offset */
133 HOWTO (R_AVR_32, /* type */
134 0, /* rightshift */
135 2, /* size (0 = byte, 1 = short, 2 = long) */
136 32, /* bitsize */
137 FALSE, /* pc_relative */
138 0, /* bitpos */
139 complain_overflow_bitfield, /* complain_on_overflow */
140 bfd_elf_generic_reloc, /* special_function */
141 "R_AVR_32", /* name */
142 FALSE, /* partial_inplace */
143 0xffffffff, /* src_mask */
144 0xffffffff, /* dst_mask */
145 FALSE), /* pcrel_offset */
147 /* A 7 bit PC relative relocation. */
148 HOWTO (R_AVR_7_PCREL, /* type */
149 1, /* rightshift */
150 1, /* size (0 = byte, 1 = short, 2 = long) */
151 7, /* bitsize */
152 TRUE, /* pc_relative */
153 3, /* bitpos */
154 complain_overflow_bitfield, /* complain_on_overflow */
155 bfd_elf_generic_reloc, /* special_function */
156 "R_AVR_7_PCREL", /* name */
157 FALSE, /* partial_inplace */
158 0xffff, /* src_mask */
159 0xffff, /* dst_mask */
160 TRUE), /* pcrel_offset */
162 /* A 13 bit PC relative relocation. */
163 HOWTO (R_AVR_13_PCREL, /* type */
164 1, /* rightshift */
165 1, /* size (0 = byte, 1 = short, 2 = long) */
166 13, /* bitsize */
167 TRUE, /* pc_relative */
168 0, /* bitpos */
169 complain_overflow_bitfield, /* complain_on_overflow */
170 bfd_elf_generic_reloc, /* special_function */
171 "R_AVR_13_PCREL", /* name */
172 FALSE, /* partial_inplace */
173 0xfff, /* src_mask */
174 0xfff, /* dst_mask */
175 TRUE), /* pcrel_offset */
177 /* A 16 bit absolute relocation. */
178 HOWTO (R_AVR_16, /* type */
179 0, /* rightshift */
180 1, /* size (0 = byte, 1 = short, 2 = long) */
181 16, /* bitsize */
182 FALSE, /* pc_relative */
183 0, /* bitpos */
184 complain_overflow_dont, /* complain_on_overflow */
185 bfd_elf_generic_reloc, /* special_function */
186 "R_AVR_16", /* name */
187 FALSE, /* partial_inplace */
188 0xffff, /* src_mask */
189 0xffff, /* dst_mask */
190 FALSE), /* pcrel_offset */
192 /* A 16 bit absolute relocation for command address
193 Will be changed when linker stubs are needed. */
194 HOWTO (R_AVR_16_PM, /* type */
195 1, /* rightshift */
196 1, /* size (0 = byte, 1 = short, 2 = long) */
197 16, /* bitsize */
198 FALSE, /* pc_relative */
199 0, /* bitpos */
200 complain_overflow_bitfield, /* complain_on_overflow */
201 bfd_elf_generic_reloc, /* special_function */
202 "R_AVR_16_PM", /* name */
203 FALSE, /* partial_inplace */
204 0xffff, /* src_mask */
205 0xffff, /* dst_mask */
206 FALSE), /* pcrel_offset */
207 /* A low 8 bit absolute relocation of 16 bit address.
208 For LDI command. */
209 HOWTO (R_AVR_LO8_LDI, /* type */
210 0, /* rightshift */
211 1, /* size (0 = byte, 1 = short, 2 = long) */
212 8, /* bitsize */
213 FALSE, /* pc_relative */
214 0, /* bitpos */
215 complain_overflow_dont, /* complain_on_overflow */
216 bfd_elf_generic_reloc, /* special_function */
217 "R_AVR_LO8_LDI", /* name */
218 FALSE, /* partial_inplace */
219 0xffff, /* src_mask */
220 0xffff, /* dst_mask */
221 FALSE), /* pcrel_offset */
222 /* A high 8 bit absolute relocation of 16 bit address.
223 For LDI command. */
224 HOWTO (R_AVR_HI8_LDI, /* type */
225 8, /* rightshift */
226 1, /* size (0 = byte, 1 = short, 2 = long) */
227 8, /* bitsize */
228 FALSE, /* pc_relative */
229 0, /* bitpos */
230 complain_overflow_dont, /* complain_on_overflow */
231 bfd_elf_generic_reloc, /* special_function */
232 "R_AVR_HI8_LDI", /* name */
233 FALSE, /* partial_inplace */
234 0xffff, /* src_mask */
235 0xffff, /* dst_mask */
236 FALSE), /* pcrel_offset */
237 /* A high 6 bit absolute relocation of 22 bit address.
238 For LDI command. As well second most significant 8 bit value of
239 a 32 bit link-time constant. */
240 HOWTO (R_AVR_HH8_LDI, /* type */
241 16, /* rightshift */
242 1, /* size (0 = byte, 1 = short, 2 = long) */
243 8, /* bitsize */
244 FALSE, /* pc_relative */
245 0, /* bitpos */
246 complain_overflow_dont, /* complain_on_overflow */
247 bfd_elf_generic_reloc, /* special_function */
248 "R_AVR_HH8_LDI", /* name */
249 FALSE, /* partial_inplace */
250 0xffff, /* src_mask */
251 0xffff, /* dst_mask */
252 FALSE), /* pcrel_offset */
253 /* A negative low 8 bit absolute relocation of 16 bit address.
254 For LDI command. */
255 HOWTO (R_AVR_LO8_LDI_NEG, /* type */
256 0, /* rightshift */
257 1, /* size (0 = byte, 1 = short, 2 = long) */
258 8, /* bitsize */
259 FALSE, /* pc_relative */
260 0, /* bitpos */
261 complain_overflow_dont, /* complain_on_overflow */
262 bfd_elf_generic_reloc, /* special_function */
263 "R_AVR_LO8_LDI_NEG", /* name */
264 FALSE, /* partial_inplace */
265 0xffff, /* src_mask */
266 0xffff, /* dst_mask */
267 FALSE), /* pcrel_offset */
268 /* A negative high 8 bit absolute relocation of 16 bit address.
269 For LDI command. */
270 HOWTO (R_AVR_HI8_LDI_NEG, /* type */
271 8, /* rightshift */
272 1, /* size (0 = byte, 1 = short, 2 = long) */
273 8, /* bitsize */
274 FALSE, /* pc_relative */
275 0, /* bitpos */
276 complain_overflow_dont, /* complain_on_overflow */
277 bfd_elf_generic_reloc, /* special_function */
278 "R_AVR_HI8_LDI_NEG", /* name */
279 FALSE, /* partial_inplace */
280 0xffff, /* src_mask */
281 0xffff, /* dst_mask */
282 FALSE), /* pcrel_offset */
283 /* A negative high 6 bit absolute relocation of 22 bit address.
284 For LDI command. */
285 HOWTO (R_AVR_HH8_LDI_NEG, /* type */
286 16, /* rightshift */
287 1, /* size (0 = byte, 1 = short, 2 = long) */
288 8, /* bitsize */
289 FALSE, /* pc_relative */
290 0, /* bitpos */
291 complain_overflow_dont, /* complain_on_overflow */
292 bfd_elf_generic_reloc, /* special_function */
293 "R_AVR_HH8_LDI_NEG", /* name */
294 FALSE, /* partial_inplace */
295 0xffff, /* src_mask */
296 0xffff, /* dst_mask */
297 FALSE), /* pcrel_offset */
298 /* A low 8 bit absolute relocation of 24 bit program memory address.
299 For LDI command. Will not be changed when linker stubs are needed. */
300 HOWTO (R_AVR_LO8_LDI_PM, /* type */
301 1, /* rightshift */
302 1, /* size (0 = byte, 1 = short, 2 = long) */
303 8, /* bitsize */
304 FALSE, /* pc_relative */
305 0, /* bitpos */
306 complain_overflow_dont, /* complain_on_overflow */
307 bfd_elf_generic_reloc, /* special_function */
308 "R_AVR_LO8_LDI_PM", /* name */
309 FALSE, /* partial_inplace */
310 0xffff, /* src_mask */
311 0xffff, /* dst_mask */
312 FALSE), /* pcrel_offset */
313 /* A low 8 bit absolute relocation of 24 bit program memory address.
314 For LDI command. Will not be changed when linker stubs are needed. */
315 HOWTO (R_AVR_HI8_LDI_PM, /* type */
316 9, /* rightshift */
317 1, /* size (0 = byte, 1 = short, 2 = long) */
318 8, /* bitsize */
319 FALSE, /* pc_relative */
320 0, /* bitpos */
321 complain_overflow_dont, /* complain_on_overflow */
322 bfd_elf_generic_reloc, /* special_function */
323 "R_AVR_HI8_LDI_PM", /* name */
324 FALSE, /* partial_inplace */
325 0xffff, /* src_mask */
326 0xffff, /* dst_mask */
327 FALSE), /* pcrel_offset */
328 /* A low 8 bit absolute relocation of 24 bit program memory address.
329 For LDI command. Will not be changed when linker stubs are needed. */
330 HOWTO (R_AVR_HH8_LDI_PM, /* type */
331 17, /* rightshift */
332 1, /* size (0 = byte, 1 = short, 2 = long) */
333 8, /* bitsize */
334 FALSE, /* pc_relative */
335 0, /* bitpos */
336 complain_overflow_dont, /* complain_on_overflow */
337 bfd_elf_generic_reloc, /* special_function */
338 "R_AVR_HH8_LDI_PM", /* name */
339 FALSE, /* partial_inplace */
340 0xffff, /* src_mask */
341 0xffff, /* dst_mask */
342 FALSE), /* pcrel_offset */
343 /* A low 8 bit absolute relocation of 24 bit program memory address.
344 For LDI command. Will not be changed when linker stubs are needed. */
345 HOWTO (R_AVR_LO8_LDI_PM_NEG, /* type */
346 1, /* rightshift */
347 1, /* size (0 = byte, 1 = short, 2 = long) */
348 8, /* bitsize */
349 FALSE, /* pc_relative */
350 0, /* bitpos */
351 complain_overflow_dont, /* complain_on_overflow */
352 bfd_elf_generic_reloc, /* special_function */
353 "R_AVR_LO8_LDI_PM_NEG", /* name */
354 FALSE, /* partial_inplace */
355 0xffff, /* src_mask */
356 0xffff, /* dst_mask */
357 FALSE), /* pcrel_offset */
358 /* A low 8 bit absolute relocation of 24 bit program memory address.
359 For LDI command. Will not be changed when linker stubs are needed. */
360 HOWTO (R_AVR_HI8_LDI_PM_NEG, /* type */
361 9, /* rightshift */
362 1, /* size (0 = byte, 1 = short, 2 = long) */
363 8, /* bitsize */
364 FALSE, /* pc_relative */
365 0, /* bitpos */
366 complain_overflow_dont, /* complain_on_overflow */
367 bfd_elf_generic_reloc, /* special_function */
368 "R_AVR_HI8_LDI_PM_NEG", /* name */
369 FALSE, /* partial_inplace */
370 0xffff, /* src_mask */
371 0xffff, /* dst_mask */
372 FALSE), /* pcrel_offset */
373 /* A low 8 bit absolute relocation of 24 bit program memory address.
374 For LDI command. Will not be changed when linker stubs are needed. */
375 HOWTO (R_AVR_HH8_LDI_PM_NEG, /* type */
376 17, /* rightshift */
377 1, /* size (0 = byte, 1 = short, 2 = long) */
378 8, /* bitsize */
379 FALSE, /* pc_relative */
380 0, /* bitpos */
381 complain_overflow_dont, /* complain_on_overflow */
382 bfd_elf_generic_reloc, /* special_function */
383 "R_AVR_HH8_LDI_PM_NEG", /* name */
384 FALSE, /* partial_inplace */
385 0xffff, /* src_mask */
386 0xffff, /* dst_mask */
387 FALSE), /* pcrel_offset */
388 /* Relocation for CALL command in ATmega. */
389 HOWTO (R_AVR_CALL, /* type */
390 1, /* rightshift */
391 2, /* size (0 = byte, 1 = short, 2 = long) */
392 23, /* bitsize */
393 FALSE, /* pc_relative */
394 0, /* bitpos */
395 complain_overflow_dont,/* complain_on_overflow */
396 bfd_elf_generic_reloc, /* special_function */
397 "R_AVR_CALL", /* name */
398 FALSE, /* partial_inplace */
399 0xffffffff, /* src_mask */
400 0xffffffff, /* dst_mask */
401 FALSE), /* pcrel_offset */
402 /* A 16 bit absolute relocation of 16 bit address.
403 For LDI command. */
404 HOWTO (R_AVR_LDI, /* type */
405 0, /* rightshift */
406 1, /* size (0 = byte, 1 = short, 2 = long) */
407 16, /* bitsize */
408 FALSE, /* pc_relative */
409 0, /* bitpos */
410 complain_overflow_dont,/* complain_on_overflow */
411 bfd_elf_generic_reloc, /* special_function */
412 "R_AVR_LDI", /* name */
413 FALSE, /* partial_inplace */
414 0xffff, /* src_mask */
415 0xffff, /* dst_mask */
416 FALSE), /* pcrel_offset */
417 /* A 6 bit absolute relocation of 6 bit offset.
418 For ldd/sdd command. */
419 HOWTO (R_AVR_6, /* type */
420 0, /* rightshift */
421 0, /* size (0 = byte, 1 = short, 2 = long) */
422 6, /* bitsize */
423 FALSE, /* pc_relative */
424 0, /* bitpos */
425 complain_overflow_dont,/* complain_on_overflow */
426 bfd_elf_generic_reloc, /* special_function */
427 "R_AVR_6", /* name */
428 FALSE, /* partial_inplace */
429 0xffff, /* src_mask */
430 0xffff, /* dst_mask */
431 FALSE), /* pcrel_offset */
432 /* A 6 bit absolute relocation of 6 bit offset.
433 For sbiw/adiw command. */
434 HOWTO (R_AVR_6_ADIW, /* type */
435 0, /* rightshift */
436 0, /* size (0 = byte, 1 = short, 2 = long) */
437 6, /* bitsize */
438 FALSE, /* pc_relative */
439 0, /* bitpos */
440 complain_overflow_dont,/* complain_on_overflow */
441 bfd_elf_generic_reloc, /* special_function */
442 "R_AVR_6_ADIW", /* name */
443 FALSE, /* partial_inplace */
444 0xffff, /* src_mask */
445 0xffff, /* dst_mask */
446 FALSE), /* pcrel_offset */
447 /* Most significant 8 bit value of a 32 bit link-time constant. */
448 HOWTO (R_AVR_MS8_LDI, /* type */
449 24, /* rightshift */
450 1, /* size (0 = byte, 1 = short, 2 = long) */
451 8, /* bitsize */
452 FALSE, /* pc_relative */
453 0, /* bitpos */
454 complain_overflow_dont, /* complain_on_overflow */
455 bfd_elf_generic_reloc, /* special_function */
456 "R_AVR_MS8_LDI", /* name */
457 FALSE, /* partial_inplace */
458 0xffff, /* src_mask */
459 0xffff, /* dst_mask */
460 FALSE), /* pcrel_offset */
461 /* Negative most significant 8 bit value of a 32 bit link-time constant. */
462 HOWTO (R_AVR_MS8_LDI_NEG, /* type */
463 24, /* rightshift */
464 1, /* size (0 = byte, 1 = short, 2 = long) */
465 8, /* bitsize */
466 FALSE, /* pc_relative */
467 0, /* bitpos */
468 complain_overflow_dont, /* complain_on_overflow */
469 bfd_elf_generic_reloc, /* special_function */
470 "R_AVR_MS8_LDI_NEG", /* name */
471 FALSE, /* partial_inplace */
472 0xffff, /* src_mask */
473 0xffff, /* dst_mask */
474 FALSE), /* pcrel_offset */
475 /* A low 8 bit absolute relocation of 24 bit program memory address.
476 For LDI command. Will be changed when linker stubs are needed. */
477 HOWTO (R_AVR_LO8_LDI_GS, /* type */
478 1, /* rightshift */
479 1, /* size (0 = byte, 1 = short, 2 = long) */
480 8, /* bitsize */
481 FALSE, /* pc_relative */
482 0, /* bitpos */
483 complain_overflow_dont, /* complain_on_overflow */
484 bfd_elf_generic_reloc, /* special_function */
485 "R_AVR_LO8_LDI_GS", /* name */
486 FALSE, /* partial_inplace */
487 0xffff, /* src_mask */
488 0xffff, /* dst_mask */
489 FALSE), /* pcrel_offset */
490 /* A low 8 bit absolute relocation of 24 bit program memory address.
491 For LDI command. Will be changed when linker stubs are needed. */
492 HOWTO (R_AVR_HI8_LDI_GS, /* type */
493 9, /* rightshift */
494 1, /* size (0 = byte, 1 = short, 2 = long) */
495 8, /* bitsize */
496 FALSE, /* pc_relative */
497 0, /* bitpos */
498 complain_overflow_dont, /* complain_on_overflow */
499 bfd_elf_generic_reloc, /* special_function */
500 "R_AVR_HI8_LDI_GS", /* name */
501 FALSE, /* partial_inplace */
502 0xffff, /* src_mask */
503 0xffff, /* dst_mask */
504 FALSE), /* pcrel_offset */
505 /* 8 bit offset. */
506 HOWTO (R_AVR_8, /* type */
507 0, /* rightshift */
508 0, /* size (0 = byte, 1 = short, 2 = long) */
509 8, /* bitsize */
510 FALSE, /* pc_relative */
511 0, /* bitpos */
512 complain_overflow_bitfield,/* complain_on_overflow */
513 bfd_elf_generic_reloc, /* special_function */
514 "R_AVR_8", /* name */
515 FALSE, /* partial_inplace */
516 0x000000ff, /* src_mask */
517 0x000000ff, /* dst_mask */
518 FALSE), /* pcrel_offset */
521 /* Map BFD reloc types to AVR ELF reloc types. */
523 struct avr_reloc_map
525 bfd_reloc_code_real_type bfd_reloc_val;
526 unsigned int elf_reloc_val;
529 static const struct avr_reloc_map avr_reloc_map[] =
531 { BFD_RELOC_NONE, R_AVR_NONE },
532 { BFD_RELOC_32, R_AVR_32 },
533 { BFD_RELOC_AVR_7_PCREL, R_AVR_7_PCREL },
534 { BFD_RELOC_AVR_13_PCREL, R_AVR_13_PCREL },
535 { BFD_RELOC_16, R_AVR_16 },
536 { BFD_RELOC_AVR_16_PM, R_AVR_16_PM },
537 { BFD_RELOC_AVR_LO8_LDI, R_AVR_LO8_LDI},
538 { BFD_RELOC_AVR_HI8_LDI, R_AVR_HI8_LDI },
539 { BFD_RELOC_AVR_HH8_LDI, R_AVR_HH8_LDI },
540 { BFD_RELOC_AVR_MS8_LDI, R_AVR_MS8_LDI },
541 { BFD_RELOC_AVR_LO8_LDI_NEG, R_AVR_LO8_LDI_NEG },
542 { BFD_RELOC_AVR_HI8_LDI_NEG, R_AVR_HI8_LDI_NEG },
543 { BFD_RELOC_AVR_HH8_LDI_NEG, R_AVR_HH8_LDI_NEG },
544 { BFD_RELOC_AVR_MS8_LDI_NEG, R_AVR_MS8_LDI_NEG },
545 { BFD_RELOC_AVR_LO8_LDI_PM, R_AVR_LO8_LDI_PM },
546 { BFD_RELOC_AVR_LO8_LDI_GS, R_AVR_LO8_LDI_GS },
547 { BFD_RELOC_AVR_HI8_LDI_PM, R_AVR_HI8_LDI_PM },
548 { BFD_RELOC_AVR_HI8_LDI_GS, R_AVR_HI8_LDI_GS },
549 { BFD_RELOC_AVR_HH8_LDI_PM, R_AVR_HH8_LDI_PM },
550 { BFD_RELOC_AVR_LO8_LDI_PM_NEG, R_AVR_LO8_LDI_PM_NEG },
551 { BFD_RELOC_AVR_HI8_LDI_PM_NEG, R_AVR_HI8_LDI_PM_NEG },
552 { BFD_RELOC_AVR_HH8_LDI_PM_NEG, R_AVR_HH8_LDI_PM_NEG },
553 { BFD_RELOC_AVR_CALL, R_AVR_CALL },
554 { BFD_RELOC_AVR_LDI, R_AVR_LDI },
555 { BFD_RELOC_AVR_6, R_AVR_6 },
556 { BFD_RELOC_AVR_6_ADIW, R_AVR_6_ADIW },
557 { BFD_RELOC_8, R_AVR_8 }
560 /* Meant to be filled one day with the wrap around address for the
561 specific device. I.e. should get the value 0x4000 for 16k devices,
562 0x8000 for 32k devices and so on.
564 We initialize it here with a value of 0x1000000 resulting in
565 that we will never suggest a wrap-around jump during relaxation.
566 The logic of the source code later on assumes that in
567 avr_pc_wrap_around one single bit is set. */
568 static bfd_vma avr_pc_wrap_around = 0x10000000;
570 /* If this variable holds a value different from zero, the linker relaxation
571 machine will try to optimize call/ret sequences by a single jump
572 instruction. This option could be switched off by a linker switch. */
573 static int avr_replace_call_ret_sequences = 1;
575 /* Initialize an entry in the stub hash table. */
577 static struct bfd_hash_entry *
578 stub_hash_newfunc (struct bfd_hash_entry *entry,
579 struct bfd_hash_table *table,
580 const char *string)
582 /* Allocate the structure if it has not already been allocated by a
583 subclass. */
584 if (entry == NULL)
586 entry = bfd_hash_allocate (table,
587 sizeof (struct elf32_avr_stub_hash_entry));
588 if (entry == NULL)
589 return entry;
592 /* Call the allocation method of the superclass. */
593 entry = bfd_hash_newfunc (entry, table, string);
594 if (entry != NULL)
596 struct elf32_avr_stub_hash_entry *hsh;
598 /* Initialize the local fields. */
599 hsh = avr_stub_hash_entry (entry);
600 hsh->stub_offset = 0;
601 hsh->target_value = 0;
604 return entry;
607 /* This function is just a straight passthrough to the real
608 function in linker.c. Its prupose is so that its address
609 can be compared inside the avr_link_hash_table macro. */
611 static struct bfd_hash_entry *
612 elf32_avr_link_hash_newfunc (struct bfd_hash_entry * entry,
613 struct bfd_hash_table * table,
614 const char * string)
616 return _bfd_elf_link_hash_newfunc (entry, table, string);
619 /* Create the derived linker hash table. The AVR ELF port uses the derived
620 hash table to keep information specific to the AVR ELF linker (without
621 using static variables). */
623 static struct bfd_link_hash_table *
624 elf32_avr_link_hash_table_create (bfd *abfd)
626 struct elf32_avr_link_hash_table *htab;
627 bfd_size_type amt = sizeof (*htab);
629 htab = bfd_malloc (amt);
630 if (htab == NULL)
631 return NULL;
633 if (!_bfd_elf_link_hash_table_init (&htab->etab, abfd,
634 elf32_avr_link_hash_newfunc,
635 sizeof (struct elf_link_hash_entry),
636 AVR_ELF_DATA))
638 free (htab);
639 return NULL;
642 /* Init the stub hash table too. */
643 if (!bfd_hash_table_init (&htab->bstab, stub_hash_newfunc,
644 sizeof (struct elf32_avr_stub_hash_entry)))
645 return NULL;
647 htab->stub_bfd = NULL;
648 htab->stub_sec = NULL;
650 /* Initialize the address mapping table. */
651 htab->amt_stub_offsets = NULL;
652 htab->amt_destination_addr = NULL;
653 htab->amt_entry_cnt = 0;
654 htab->amt_max_entry_cnt = 0;
656 return &htab->etab.root;
659 /* Free the derived linker hash table. */
661 static void
662 elf32_avr_link_hash_table_free (struct bfd_link_hash_table *btab)
664 struct elf32_avr_link_hash_table *htab
665 = (struct elf32_avr_link_hash_table *) btab;
667 /* Free the address mapping table. */
668 if (htab->amt_stub_offsets != NULL)
669 free (htab->amt_stub_offsets);
670 if (htab->amt_destination_addr != NULL)
671 free (htab->amt_destination_addr);
673 bfd_hash_table_free (&htab->bstab);
674 _bfd_generic_link_hash_table_free (btab);
677 /* Calculates the effective distance of a pc relative jump/call. */
679 static int
680 avr_relative_distance_considering_wrap_around (unsigned int distance)
682 unsigned int wrap_around_mask = avr_pc_wrap_around - 1;
683 int dist_with_wrap_around = distance & wrap_around_mask;
685 if (dist_with_wrap_around > ((int) (avr_pc_wrap_around >> 1)))
686 dist_with_wrap_around -= avr_pc_wrap_around;
688 return dist_with_wrap_around;
692 static reloc_howto_type *
693 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
694 bfd_reloc_code_real_type code)
696 unsigned int i;
698 for (i = 0;
699 i < sizeof (avr_reloc_map) / sizeof (struct avr_reloc_map);
700 i++)
701 if (avr_reloc_map[i].bfd_reloc_val == code)
702 return &elf_avr_howto_table[avr_reloc_map[i].elf_reloc_val];
704 return NULL;
707 static reloc_howto_type *
708 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
709 const char *r_name)
711 unsigned int i;
713 for (i = 0;
714 i < sizeof (elf_avr_howto_table) / sizeof (elf_avr_howto_table[0]);
715 i++)
716 if (elf_avr_howto_table[i].name != NULL
717 && strcasecmp (elf_avr_howto_table[i].name, r_name) == 0)
718 return &elf_avr_howto_table[i];
720 return NULL;
723 /* Set the howto pointer for an AVR ELF reloc. */
725 static void
726 avr_info_to_howto_rela (bfd *abfd ATTRIBUTE_UNUSED,
727 arelent *cache_ptr,
728 Elf_Internal_Rela *dst)
730 unsigned int r_type;
732 r_type = ELF32_R_TYPE (dst->r_info);
733 BFD_ASSERT (r_type < (unsigned int) R_AVR_max);
734 cache_ptr->howto = &elf_avr_howto_table[r_type];
737 static bfd_boolean
738 avr_stub_is_required_for_16_bit_reloc (bfd_vma relocation)
740 return (relocation >= 0x020000);
743 /* Returns the address of the corresponding stub if there is one.
744 Returns otherwise an address above 0x020000. This function
745 could also be used, if there is no knowledge on the section where
746 the destination is found. */
748 static bfd_vma
749 avr_get_stub_addr (bfd_vma srel,
750 struct elf32_avr_link_hash_table *htab)
752 unsigned int sindex;
753 bfd_vma stub_sec_addr =
754 (htab->stub_sec->output_section->vma +
755 htab->stub_sec->output_offset);
757 for (sindex = 0; sindex < htab->amt_max_entry_cnt; sindex ++)
758 if (htab->amt_destination_addr[sindex] == srel)
759 return htab->amt_stub_offsets[sindex] + stub_sec_addr;
761 /* Return an address that could not be reached by 16 bit relocs. */
762 return 0x020000;
765 /* Perform a single relocation. By default we use the standard BFD
766 routines, but a few relocs, we have to do them ourselves. */
768 static bfd_reloc_status_type
769 avr_final_link_relocate (reloc_howto_type * howto,
770 bfd * input_bfd,
771 asection * input_section,
772 bfd_byte * contents,
773 Elf_Internal_Rela * rel,
774 bfd_vma relocation,
775 struct elf32_avr_link_hash_table * htab)
777 bfd_reloc_status_type r = bfd_reloc_ok;
778 bfd_vma x;
779 bfd_signed_vma srel;
780 bfd_signed_vma reloc_addr;
781 bfd_boolean use_stubs = FALSE;
782 /* Usually is 0, unless we are generating code for a bootloader. */
783 bfd_signed_vma base_addr = htab->vector_base;
785 /* Absolute addr of the reloc in the final excecutable. */
786 reloc_addr = rel->r_offset + input_section->output_section->vma
787 + input_section->output_offset;
789 switch (howto->type)
791 case R_AVR_7_PCREL:
792 contents += rel->r_offset;
793 srel = (bfd_signed_vma) relocation;
794 srel += rel->r_addend;
795 srel -= rel->r_offset;
796 srel -= 2; /* Branch instructions add 2 to the PC... */
797 srel -= (input_section->output_section->vma +
798 input_section->output_offset);
800 if (srel & 1)
801 return bfd_reloc_outofrange;
802 if (srel > ((1 << 7) - 1) || (srel < - (1 << 7)))
803 return bfd_reloc_overflow;
804 x = bfd_get_16 (input_bfd, contents);
805 x = (x & 0xfc07) | (((srel >> 1) << 3) & 0x3f8);
806 bfd_put_16 (input_bfd, x, contents);
807 break;
809 case R_AVR_13_PCREL:
810 contents += rel->r_offset;
811 srel = (bfd_signed_vma) relocation;
812 srel += rel->r_addend;
813 srel -= rel->r_offset;
814 srel -= 2; /* Branch instructions add 2 to the PC... */
815 srel -= (input_section->output_section->vma +
816 input_section->output_offset);
818 if (srel & 1)
819 return bfd_reloc_outofrange;
821 srel = avr_relative_distance_considering_wrap_around (srel);
823 /* AVR addresses commands as words. */
824 srel >>= 1;
826 /* Check for overflow. */
827 if (srel < -2048 || srel > 2047)
829 /* Relative distance is too large. */
831 /* Always apply WRAPAROUND for avr2, avr25, and avr4. */
832 switch (bfd_get_mach (input_bfd))
834 case bfd_mach_avr2:
835 case bfd_mach_avr25:
836 case bfd_mach_avr4:
837 break;
839 default:
840 return bfd_reloc_overflow;
844 x = bfd_get_16 (input_bfd, contents);
845 x = (x & 0xf000) | (srel & 0xfff);
846 bfd_put_16 (input_bfd, x, contents);
847 break;
849 case R_AVR_LO8_LDI:
850 contents += rel->r_offset;
851 srel = (bfd_signed_vma) relocation + rel->r_addend;
852 x = bfd_get_16 (input_bfd, contents);
853 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
854 bfd_put_16 (input_bfd, x, contents);
855 break;
857 case R_AVR_LDI:
858 contents += rel->r_offset;
859 srel = (bfd_signed_vma) relocation + rel->r_addend;
860 if (((srel > 0) && (srel & 0xffff) > 255)
861 || ((srel < 0) && ((-srel) & 0xffff) > 128))
862 /* Remove offset for data/eeprom section. */
863 return bfd_reloc_overflow;
865 x = bfd_get_16 (input_bfd, contents);
866 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
867 bfd_put_16 (input_bfd, x, contents);
868 break;
870 case R_AVR_6:
871 contents += rel->r_offset;
872 srel = (bfd_signed_vma) relocation + rel->r_addend;
873 if (((srel & 0xffff) > 63) || (srel < 0))
874 /* Remove offset for data/eeprom section. */
875 return bfd_reloc_overflow;
876 x = bfd_get_16 (input_bfd, contents);
877 x = (x & 0xd3f8) | ((srel & 7) | ((srel & (3 << 3)) << 7)
878 | ((srel & (1 << 5)) << 8));
879 bfd_put_16 (input_bfd, x, contents);
880 break;
882 case R_AVR_6_ADIW:
883 contents += rel->r_offset;
884 srel = (bfd_signed_vma) relocation + rel->r_addend;
885 if (((srel & 0xffff) > 63) || (srel < 0))
886 /* Remove offset for data/eeprom section. */
887 return bfd_reloc_overflow;
888 x = bfd_get_16 (input_bfd, contents);
889 x = (x & 0xff30) | (srel & 0xf) | ((srel & 0x30) << 2);
890 bfd_put_16 (input_bfd, x, contents);
891 break;
893 case R_AVR_HI8_LDI:
894 contents += rel->r_offset;
895 srel = (bfd_signed_vma) relocation + rel->r_addend;
896 srel = (srel >> 8) & 0xff;
897 x = bfd_get_16 (input_bfd, contents);
898 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
899 bfd_put_16 (input_bfd, x, contents);
900 break;
902 case R_AVR_HH8_LDI:
903 contents += rel->r_offset;
904 srel = (bfd_signed_vma) relocation + rel->r_addend;
905 srel = (srel >> 16) & 0xff;
906 x = bfd_get_16 (input_bfd, contents);
907 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
908 bfd_put_16 (input_bfd, x, contents);
909 break;
911 case R_AVR_MS8_LDI:
912 contents += rel->r_offset;
913 srel = (bfd_signed_vma) relocation + rel->r_addend;
914 srel = (srel >> 24) & 0xff;
915 x = bfd_get_16 (input_bfd, contents);
916 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
917 bfd_put_16 (input_bfd, x, contents);
918 break;
920 case R_AVR_LO8_LDI_NEG:
921 contents += rel->r_offset;
922 srel = (bfd_signed_vma) relocation + rel->r_addend;
923 srel = -srel;
924 x = bfd_get_16 (input_bfd, contents);
925 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
926 bfd_put_16 (input_bfd, x, contents);
927 break;
929 case R_AVR_HI8_LDI_NEG:
930 contents += rel->r_offset;
931 srel = (bfd_signed_vma) relocation + rel->r_addend;
932 srel = -srel;
933 srel = (srel >> 8) & 0xff;
934 x = bfd_get_16 (input_bfd, contents);
935 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
936 bfd_put_16 (input_bfd, x, contents);
937 break;
939 case R_AVR_HH8_LDI_NEG:
940 contents += rel->r_offset;
941 srel = (bfd_signed_vma) relocation + rel->r_addend;
942 srel = -srel;
943 srel = (srel >> 16) & 0xff;
944 x = bfd_get_16 (input_bfd, contents);
945 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
946 bfd_put_16 (input_bfd, x, contents);
947 break;
949 case R_AVR_MS8_LDI_NEG:
950 contents += rel->r_offset;
951 srel = (bfd_signed_vma) relocation + rel->r_addend;
952 srel = -srel;
953 srel = (srel >> 24) & 0xff;
954 x = bfd_get_16 (input_bfd, contents);
955 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
956 bfd_put_16 (input_bfd, x, contents);
957 break;
959 case R_AVR_LO8_LDI_GS:
960 use_stubs = (!htab->no_stubs);
961 /* Fall through. */
962 case R_AVR_LO8_LDI_PM:
963 contents += rel->r_offset;
964 srel = (bfd_signed_vma) relocation + rel->r_addend;
966 if (use_stubs
967 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
969 bfd_vma old_srel = srel;
971 /* We need to use the address of the stub instead. */
972 srel = avr_get_stub_addr (srel, htab);
973 if (debug_stubs)
974 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
975 "reloc at address 0x%x.\n",
976 (unsigned int) srel,
977 (unsigned int) old_srel,
978 (unsigned int) reloc_addr);
980 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
981 return bfd_reloc_outofrange;
984 if (srel & 1)
985 return bfd_reloc_outofrange;
986 srel = srel >> 1;
987 x = bfd_get_16 (input_bfd, contents);
988 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
989 bfd_put_16 (input_bfd, x, contents);
990 break;
992 case R_AVR_HI8_LDI_GS:
993 use_stubs = (!htab->no_stubs);
994 /* Fall through. */
995 case R_AVR_HI8_LDI_PM:
996 contents += rel->r_offset;
997 srel = (bfd_signed_vma) relocation + rel->r_addend;
999 if (use_stubs
1000 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1002 bfd_vma old_srel = srel;
1004 /* We need to use the address of the stub instead. */
1005 srel = avr_get_stub_addr (srel, htab);
1006 if (debug_stubs)
1007 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
1008 "reloc at address 0x%x.\n",
1009 (unsigned int) srel,
1010 (unsigned int) old_srel,
1011 (unsigned int) reloc_addr);
1013 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1014 return bfd_reloc_outofrange;
1017 if (srel & 1)
1018 return bfd_reloc_outofrange;
1019 srel = srel >> 1;
1020 srel = (srel >> 8) & 0xff;
1021 x = bfd_get_16 (input_bfd, contents);
1022 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1023 bfd_put_16 (input_bfd, x, contents);
1024 break;
1026 case R_AVR_HH8_LDI_PM:
1027 contents += rel->r_offset;
1028 srel = (bfd_signed_vma) relocation + rel->r_addend;
1029 if (srel & 1)
1030 return bfd_reloc_outofrange;
1031 srel = srel >> 1;
1032 srel = (srel >> 16) & 0xff;
1033 x = bfd_get_16 (input_bfd, contents);
1034 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1035 bfd_put_16 (input_bfd, x, contents);
1036 break;
1038 case R_AVR_LO8_LDI_PM_NEG:
1039 contents += rel->r_offset;
1040 srel = (bfd_signed_vma) relocation + rel->r_addend;
1041 srel = -srel;
1042 if (srel & 1)
1043 return bfd_reloc_outofrange;
1044 srel = srel >> 1;
1045 x = bfd_get_16 (input_bfd, contents);
1046 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1047 bfd_put_16 (input_bfd, x, contents);
1048 break;
1050 case R_AVR_HI8_LDI_PM_NEG:
1051 contents += rel->r_offset;
1052 srel = (bfd_signed_vma) relocation + rel->r_addend;
1053 srel = -srel;
1054 if (srel & 1)
1055 return bfd_reloc_outofrange;
1056 srel = srel >> 1;
1057 srel = (srel >> 8) & 0xff;
1058 x = bfd_get_16 (input_bfd, contents);
1059 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1060 bfd_put_16 (input_bfd, x, contents);
1061 break;
1063 case R_AVR_HH8_LDI_PM_NEG:
1064 contents += rel->r_offset;
1065 srel = (bfd_signed_vma) relocation + rel->r_addend;
1066 srel = -srel;
1067 if (srel & 1)
1068 return bfd_reloc_outofrange;
1069 srel = srel >> 1;
1070 srel = (srel >> 16) & 0xff;
1071 x = bfd_get_16 (input_bfd, contents);
1072 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1073 bfd_put_16 (input_bfd, x, contents);
1074 break;
1076 case R_AVR_CALL:
1077 contents += rel->r_offset;
1078 srel = (bfd_signed_vma) relocation + rel->r_addend;
1079 if (srel & 1)
1080 return bfd_reloc_outofrange;
1081 srel = srel >> 1;
1082 x = bfd_get_16 (input_bfd, contents);
1083 x |= ((srel & 0x10000) | ((srel << 3) & 0x1f00000)) >> 16;
1084 bfd_put_16 (input_bfd, x, contents);
1085 bfd_put_16 (input_bfd, (bfd_vma) srel & 0xffff, contents+2);
1086 break;
1088 case R_AVR_16_PM:
1089 use_stubs = (!htab->no_stubs);
1090 contents += rel->r_offset;
1091 srel = (bfd_signed_vma) relocation + rel->r_addend;
1093 if (use_stubs
1094 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1096 bfd_vma old_srel = srel;
1098 /* We need to use the address of the stub instead. */
1099 srel = avr_get_stub_addr (srel,htab);
1100 if (debug_stubs)
1101 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
1102 "reloc at address 0x%x.\n",
1103 (unsigned int) srel,
1104 (unsigned int) old_srel,
1105 (unsigned int) reloc_addr);
1107 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1108 return bfd_reloc_outofrange;
1111 if (srel & 1)
1112 return bfd_reloc_outofrange;
1113 srel = srel >> 1;
1114 bfd_put_16 (input_bfd, (bfd_vma) srel &0x00ffff, contents);
1115 break;
1117 default:
1118 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1119 contents, rel->r_offset,
1120 relocation, rel->r_addend);
1123 return r;
1126 /* Relocate an AVR ELF section. */
1128 static bfd_boolean
1129 elf32_avr_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
1130 struct bfd_link_info *info,
1131 bfd *input_bfd,
1132 asection *input_section,
1133 bfd_byte *contents,
1134 Elf_Internal_Rela *relocs,
1135 Elf_Internal_Sym *local_syms,
1136 asection **local_sections)
1138 Elf_Internal_Shdr * symtab_hdr;
1139 struct elf_link_hash_entry ** sym_hashes;
1140 Elf_Internal_Rela * rel;
1141 Elf_Internal_Rela * relend;
1142 struct elf32_avr_link_hash_table * htab = avr_link_hash_table (info);
1144 if (htab == NULL)
1145 return FALSE;
1147 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1148 sym_hashes = elf_sym_hashes (input_bfd);
1149 relend = relocs + input_section->reloc_count;
1151 for (rel = relocs; rel < relend; rel ++)
1153 reloc_howto_type * howto;
1154 unsigned long r_symndx;
1155 Elf_Internal_Sym * sym;
1156 asection * sec;
1157 struct elf_link_hash_entry * h;
1158 bfd_vma relocation;
1159 bfd_reloc_status_type r;
1160 const char * name;
1161 int r_type;
1163 r_type = ELF32_R_TYPE (rel->r_info);
1164 r_symndx = ELF32_R_SYM (rel->r_info);
1165 howto = elf_avr_howto_table + r_type;
1166 h = NULL;
1167 sym = NULL;
1168 sec = NULL;
1170 if (r_symndx < symtab_hdr->sh_info)
1172 sym = local_syms + r_symndx;
1173 sec = local_sections [r_symndx];
1174 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1176 name = bfd_elf_string_from_elf_section
1177 (input_bfd, symtab_hdr->sh_link, sym->st_name);
1178 name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
1180 else
1182 bfd_boolean unresolved_reloc, warned;
1184 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1185 r_symndx, symtab_hdr, sym_hashes,
1186 h, sec, relocation,
1187 unresolved_reloc, warned);
1189 name = h->root.root.string;
1192 if (sec != NULL && elf_discarded_section (sec))
1193 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
1194 rel, relend, howto, contents);
1196 if (info->relocatable)
1197 continue;
1199 r = avr_final_link_relocate (howto, input_bfd, input_section,
1200 contents, rel, relocation, htab);
1202 if (r != bfd_reloc_ok)
1204 const char * msg = (const char *) NULL;
1206 switch (r)
1208 case bfd_reloc_overflow:
1209 r = info->callbacks->reloc_overflow
1210 (info, (h ? &h->root : NULL),
1211 name, howto->name, (bfd_vma) 0,
1212 input_bfd, input_section, rel->r_offset);
1213 break;
1215 case bfd_reloc_undefined:
1216 r = info->callbacks->undefined_symbol
1217 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
1218 break;
1220 case bfd_reloc_outofrange:
1221 msg = _("internal error: out of range error");
1222 break;
1224 case bfd_reloc_notsupported:
1225 msg = _("internal error: unsupported relocation error");
1226 break;
1228 case bfd_reloc_dangerous:
1229 msg = _("internal error: dangerous relocation");
1230 break;
1232 default:
1233 msg = _("internal error: unknown error");
1234 break;
1237 if (msg)
1238 r = info->callbacks->warning
1239 (info, msg, name, input_bfd, input_section, rel->r_offset);
1241 if (! r)
1242 return FALSE;
1246 return TRUE;
1249 /* The final processing done just before writing out a AVR ELF object
1250 file. This gets the AVR architecture right based on the machine
1251 number. */
1253 static void
1254 bfd_elf_avr_final_write_processing (bfd *abfd,
1255 bfd_boolean linker ATTRIBUTE_UNUSED)
1257 unsigned long val;
1259 switch (bfd_get_mach (abfd))
1261 default:
1262 case bfd_mach_avr2:
1263 val = E_AVR_MACH_AVR2;
1264 break;
1266 case bfd_mach_avr1:
1267 val = E_AVR_MACH_AVR1;
1268 break;
1270 case bfd_mach_avr25:
1271 val = E_AVR_MACH_AVR25;
1272 break;
1274 case bfd_mach_avr3:
1275 val = E_AVR_MACH_AVR3;
1276 break;
1278 case bfd_mach_avr31:
1279 val = E_AVR_MACH_AVR31;
1280 break;
1282 case bfd_mach_avr35:
1283 val = E_AVR_MACH_AVR35;
1284 break;
1286 case bfd_mach_avr4:
1287 val = E_AVR_MACH_AVR4;
1288 break;
1290 case bfd_mach_avr5:
1291 val = E_AVR_MACH_AVR5;
1292 break;
1294 case bfd_mach_avr51:
1295 val = E_AVR_MACH_AVR51;
1296 break;
1298 case bfd_mach_avr6:
1299 val = E_AVR_MACH_AVR6;
1300 break;
1302 case bfd_mach_avrxmega1:
1303 val = E_AVR_MACH_XMEGA1;
1304 break;
1306 case bfd_mach_avrxmega2:
1307 val = E_AVR_MACH_XMEGA2;
1308 break;
1310 case bfd_mach_avrxmega3:
1311 val = E_AVR_MACH_XMEGA3;
1312 break;
1314 case bfd_mach_avrxmega4:
1315 val = E_AVR_MACH_XMEGA4;
1316 break;
1318 case bfd_mach_avrxmega5:
1319 val = E_AVR_MACH_XMEGA5;
1320 break;
1322 case bfd_mach_avrxmega6:
1323 val = E_AVR_MACH_XMEGA6;
1324 break;
1326 case bfd_mach_avrxmega7:
1327 val = E_AVR_MACH_XMEGA7;
1328 break;
1331 elf_elfheader (abfd)->e_machine = EM_AVR;
1332 elf_elfheader (abfd)->e_flags &= ~ EF_AVR_MACH;
1333 elf_elfheader (abfd)->e_flags |= val;
1334 elf_elfheader (abfd)->e_flags |= EF_AVR_LINKRELAX_PREPARED;
1337 /* Set the right machine number. */
1339 static bfd_boolean
1340 elf32_avr_object_p (bfd *abfd)
1342 unsigned int e_set = bfd_mach_avr2;
1344 if (elf_elfheader (abfd)->e_machine == EM_AVR
1345 || elf_elfheader (abfd)->e_machine == EM_AVR_OLD)
1347 int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
1349 switch (e_mach)
1351 default:
1352 case E_AVR_MACH_AVR2:
1353 e_set = bfd_mach_avr2;
1354 break;
1356 case E_AVR_MACH_AVR1:
1357 e_set = bfd_mach_avr1;
1358 break;
1360 case E_AVR_MACH_AVR25:
1361 e_set = bfd_mach_avr25;
1362 break;
1364 case E_AVR_MACH_AVR3:
1365 e_set = bfd_mach_avr3;
1366 break;
1368 case E_AVR_MACH_AVR31:
1369 e_set = bfd_mach_avr31;
1370 break;
1372 case E_AVR_MACH_AVR35:
1373 e_set = bfd_mach_avr35;
1374 break;
1376 case E_AVR_MACH_AVR4:
1377 e_set = bfd_mach_avr4;
1378 break;
1380 case E_AVR_MACH_AVR5:
1381 e_set = bfd_mach_avr5;
1382 break;
1384 case E_AVR_MACH_AVR51:
1385 e_set = bfd_mach_avr51;
1386 break;
1388 case E_AVR_MACH_AVR6:
1389 e_set = bfd_mach_avr6;
1390 break;
1392 case E_AVR_MACH_XMEGA1:
1393 e_set = bfd_mach_avrxmega1;
1394 break;
1396 case E_AVR_MACH_XMEGA2:
1397 e_set = bfd_mach_avrxmega2;
1398 break;
1400 case E_AVR_MACH_XMEGA3:
1401 e_set = bfd_mach_avrxmega3;
1402 break;
1404 case E_AVR_MACH_XMEGA4:
1405 e_set = bfd_mach_avrxmega4;
1406 break;
1408 case E_AVR_MACH_XMEGA5:
1409 e_set = bfd_mach_avrxmega5;
1410 break;
1412 case E_AVR_MACH_XMEGA6:
1413 e_set = bfd_mach_avrxmega6;
1414 break;
1416 case E_AVR_MACH_XMEGA7:
1417 e_set = bfd_mach_avrxmega7;
1418 break;
1421 return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
1422 e_set);
1426 /* Delete some bytes from a section while changing the size of an instruction.
1427 The parameter "addr" denotes the section-relative offset pointing just
1428 behind the shrinked instruction. "addr+count" point at the first
1429 byte just behind the original unshrinked instruction. */
1431 static bfd_boolean
1432 elf32_avr_relax_delete_bytes (bfd *abfd,
1433 asection *sec,
1434 bfd_vma addr,
1435 int count)
1437 Elf_Internal_Shdr *symtab_hdr;
1438 unsigned int sec_shndx;
1439 bfd_byte *contents;
1440 Elf_Internal_Rela *irel, *irelend;
1441 Elf_Internal_Sym *isym;
1442 Elf_Internal_Sym *isymbuf = NULL;
1443 bfd_vma toaddr;
1444 struct elf_link_hash_entry **sym_hashes;
1445 struct elf_link_hash_entry **end_hashes;
1446 unsigned int symcount;
1448 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1449 sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
1450 contents = elf_section_data (sec)->this_hdr.contents;
1452 toaddr = sec->size;
1454 irel = elf_section_data (sec)->relocs;
1455 irelend = irel + sec->reloc_count;
1457 /* Actually delete the bytes. */
1458 if (toaddr - addr - count > 0)
1459 memmove (contents + addr, contents + addr + count,
1460 (size_t) (toaddr - addr - count));
1461 sec->size -= count;
1463 /* Adjust all the reloc addresses. */
1464 for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
1466 bfd_vma old_reloc_address;
1468 old_reloc_address = (sec->output_section->vma
1469 + sec->output_offset + irel->r_offset);
1471 /* Get the new reloc address. */
1472 if ((irel->r_offset > addr
1473 && irel->r_offset < toaddr))
1475 if (debug_relax)
1476 printf ("Relocation at address 0x%x needs to be moved.\n"
1477 "Old section offset: 0x%x, New section offset: 0x%x \n",
1478 (unsigned int) old_reloc_address,
1479 (unsigned int) irel->r_offset,
1480 (unsigned int) ((irel->r_offset) - count));
1482 irel->r_offset -= count;
1487 /* The reloc's own addresses are now ok. However, we need to readjust
1488 the reloc's addend, i.e. the reloc's value if two conditions are met:
1489 1.) the reloc is relative to a symbol in this section that
1490 is located in front of the shrinked instruction
1491 2.) symbol plus addend end up behind the shrinked instruction.
1493 The most common case where this happens are relocs relative to
1494 the section-start symbol.
1496 This step needs to be done for all of the sections of the bfd. */
1499 struct bfd_section *isec;
1501 for (isec = abfd->sections; isec; isec = isec->next)
1503 bfd_vma symval;
1504 bfd_vma shrinked_insn_address;
1506 if (isec->reloc_count == 0)
1507 continue;
1509 shrinked_insn_address = (sec->output_section->vma
1510 + sec->output_offset + addr - count);
1512 irel = elf_section_data (isec)->relocs;
1513 /* PR 12161: Read in the relocs for this section if necessary. */
1514 if (irel == NULL)
1515 irel = _bfd_elf_link_read_relocs (abfd, isec, NULL, NULL, FALSE);
1517 for (irelend = irel + isec->reloc_count;
1518 irel < irelend;
1519 irel++)
1521 /* Read this BFD's local symbols if we haven't done
1522 so already. */
1523 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1525 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1526 if (isymbuf == NULL)
1527 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1528 symtab_hdr->sh_info, 0,
1529 NULL, NULL, NULL);
1530 if (isymbuf == NULL)
1531 return FALSE;
1534 /* Get the value of the symbol referred to by the reloc. */
1535 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1537 /* A local symbol. */
1538 asection *sym_sec;
1540 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1541 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1542 symval = isym->st_value;
1543 /* If the reloc is absolute, it will not have
1544 a symbol or section associated with it. */
1545 if (sym_sec == sec)
1547 symval += sym_sec->output_section->vma
1548 + sym_sec->output_offset;
1550 if (debug_relax)
1551 printf ("Checking if the relocation's "
1552 "addend needs corrections.\n"
1553 "Address of anchor symbol: 0x%x \n"
1554 "Address of relocation target: 0x%x \n"
1555 "Address of relaxed insn: 0x%x \n",
1556 (unsigned int) symval,
1557 (unsigned int) (symval + irel->r_addend),
1558 (unsigned int) shrinked_insn_address);
1560 if (symval <= shrinked_insn_address
1561 && (symval + irel->r_addend) > shrinked_insn_address)
1563 irel->r_addend -= count;
1565 if (debug_relax)
1566 printf ("Relocation's addend needed to be fixed \n");
1569 /* else...Reference symbol is absolute. No adjustment needed. */
1571 /* else...Reference symbol is extern. No need for adjusting
1572 the addend. */
1575 if (elf_section_data (isec)->relocs == NULL)
1576 free (irelend - isec->reloc_count);
1580 /* Adjust the local symbols defined in this section. */
1581 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
1582 /* Fix PR 9841, there may be no local symbols. */
1583 if (isym != NULL)
1585 Elf_Internal_Sym *isymend;
1587 isymend = isym + symtab_hdr->sh_info;
1588 for (; isym < isymend; isym++)
1590 if (isym->st_shndx == sec_shndx
1591 && isym->st_value > addr
1592 && isym->st_value < toaddr)
1593 isym->st_value -= count;
1597 /* Now adjust the global symbols defined in this section. */
1598 symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
1599 - symtab_hdr->sh_info);
1600 sym_hashes = elf_sym_hashes (abfd);
1601 end_hashes = sym_hashes + symcount;
1602 for (; sym_hashes < end_hashes; sym_hashes++)
1604 struct elf_link_hash_entry *sym_hash = *sym_hashes;
1605 if ((sym_hash->root.type == bfd_link_hash_defined
1606 || sym_hash->root.type == bfd_link_hash_defweak)
1607 && sym_hash->root.u.def.section == sec
1608 && sym_hash->root.u.def.value > addr
1609 && sym_hash->root.u.def.value < toaddr)
1611 sym_hash->root.u.def.value -= count;
1615 return TRUE;
1618 /* This function handles relaxing for the avr.
1619 Many important relaxing opportunities within functions are already
1620 realized by the compiler itself.
1621 Here we try to replace call (4 bytes) -> rcall (2 bytes)
1622 and jump -> rjmp (safes also 2 bytes).
1623 As well we now optimize seqences of
1624 - call/rcall function
1625 - ret
1626 to yield
1627 - jmp/rjmp function
1628 - ret
1629 . In case that within a sequence
1630 - jmp/rjmp label
1631 - ret
1632 the ret could no longer be reached it is optimized away. In order
1633 to check if the ret is no longer needed, it is checked that the ret's address
1634 is not the target of a branch or jump within the same section, it is checked
1635 that there is no skip instruction before the jmp/rjmp and that there
1636 is no local or global label place at the address of the ret.
1638 We refrain from relaxing within sections ".vectors" and
1639 ".jumptables" in order to maintain the position of the instructions.
1640 There, however, we substitute jmp/call by a sequence rjmp,nop/rcall,nop
1641 if possible. (In future one could possibly use the space of the nop
1642 for the first instruction of the irq service function.
1644 The .jumptables sections is meant to be used for a future tablejump variant
1645 for the devices with 3-byte program counter where the table itself
1646 contains 4-byte jump instructions whose relative offset must not
1647 be changed. */
1649 static bfd_boolean
1650 elf32_avr_relax_section (bfd *abfd,
1651 asection *sec,
1652 struct bfd_link_info *link_info,
1653 bfd_boolean *again)
1655 Elf_Internal_Shdr *symtab_hdr;
1656 Elf_Internal_Rela *internal_relocs;
1657 Elf_Internal_Rela *irel, *irelend;
1658 bfd_byte *contents = NULL;
1659 Elf_Internal_Sym *isymbuf = NULL;
1660 struct elf32_avr_link_hash_table *htab;
1662 if (link_info->relocatable)
1663 (*link_info->callbacks->einfo)
1664 (_("%P%F: --relax and -r may not be used together\n"));
1666 htab = avr_link_hash_table (link_info);
1667 if (htab == NULL)
1668 return FALSE;
1670 /* Assume nothing changes. */
1671 *again = FALSE;
1673 if ((!htab->no_stubs) && (sec == htab->stub_sec))
1675 /* We are just relaxing the stub section.
1676 Let's calculate the size needed again. */
1677 bfd_size_type last_estimated_stub_section_size = htab->stub_sec->size;
1679 if (debug_relax)
1680 printf ("Relaxing the stub section. Size prior to this pass: %i\n",
1681 (int) last_estimated_stub_section_size);
1683 elf32_avr_size_stubs (htab->stub_sec->output_section->owner,
1684 link_info, FALSE);
1686 /* Check if the number of trampolines changed. */
1687 if (last_estimated_stub_section_size != htab->stub_sec->size)
1688 *again = TRUE;
1690 if (debug_relax)
1691 printf ("Size of stub section after this pass: %i\n",
1692 (int) htab->stub_sec->size);
1694 return TRUE;
1697 /* We don't have to do anything for a relocatable link, if
1698 this section does not have relocs, or if this is not a
1699 code section. */
1700 if (link_info->relocatable
1701 || (sec->flags & SEC_RELOC) == 0
1702 || sec->reloc_count == 0
1703 || (sec->flags & SEC_CODE) == 0)
1704 return TRUE;
1706 /* Check if the object file to relax uses internal symbols so that we
1707 could fix up the relocations. */
1708 if (!(elf_elfheader (abfd)->e_flags & EF_AVR_LINKRELAX_PREPARED))
1709 return TRUE;
1711 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1713 /* Get a copy of the native relocations. */
1714 internal_relocs = (_bfd_elf_link_read_relocs
1715 (abfd, sec, NULL, NULL, link_info->keep_memory));
1716 if (internal_relocs == NULL)
1717 goto error_return;
1719 /* Walk through the relocs looking for relaxing opportunities. */
1720 irelend = internal_relocs + sec->reloc_count;
1721 for (irel = internal_relocs; irel < irelend; irel++)
1723 bfd_vma symval;
1725 if ( ELF32_R_TYPE (irel->r_info) != R_AVR_13_PCREL
1726 && ELF32_R_TYPE (irel->r_info) != R_AVR_7_PCREL
1727 && ELF32_R_TYPE (irel->r_info) != R_AVR_CALL)
1728 continue;
1730 /* Get the section contents if we haven't done so already. */
1731 if (contents == NULL)
1733 /* Get cached copy if it exists. */
1734 if (elf_section_data (sec)->this_hdr.contents != NULL)
1735 contents = elf_section_data (sec)->this_hdr.contents;
1736 else
1738 /* Go get them off disk. */
1739 if (! bfd_malloc_and_get_section (abfd, sec, &contents))
1740 goto error_return;
1744 /* Read this BFD's local symbols if we haven't done so already. */
1745 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1747 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1748 if (isymbuf == NULL)
1749 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1750 symtab_hdr->sh_info, 0,
1751 NULL, NULL, NULL);
1752 if (isymbuf == NULL)
1753 goto error_return;
1757 /* Get the value of the symbol referred to by the reloc. */
1758 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1760 /* A local symbol. */
1761 Elf_Internal_Sym *isym;
1762 asection *sym_sec;
1764 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1765 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1766 symval = isym->st_value;
1767 /* If the reloc is absolute, it will not have
1768 a symbol or section associated with it. */
1769 if (sym_sec)
1770 symval += sym_sec->output_section->vma
1771 + sym_sec->output_offset;
1773 else
1775 unsigned long indx;
1776 struct elf_link_hash_entry *h;
1778 /* An external symbol. */
1779 indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
1780 h = elf_sym_hashes (abfd)[indx];
1781 BFD_ASSERT (h != NULL);
1782 if (h->root.type != bfd_link_hash_defined
1783 && h->root.type != bfd_link_hash_defweak)
1784 /* This appears to be a reference to an undefined
1785 symbol. Just ignore it--it will be caught by the
1786 regular reloc processing. */
1787 continue;
1789 symval = (h->root.u.def.value
1790 + h->root.u.def.section->output_section->vma
1791 + h->root.u.def.section->output_offset);
1794 /* For simplicity of coding, we are going to modify the section
1795 contents, the section relocs, and the BFD symbol table. We
1796 must tell the rest of the code not to free up this
1797 information. It would be possible to instead create a table
1798 of changes which have to be made, as is done in coff-mips.c;
1799 that would be more work, but would require less memory when
1800 the linker is run. */
1801 switch (ELF32_R_TYPE (irel->r_info))
1803 /* Try to turn a 22-bit absolute call/jump into an 13-bit
1804 pc-relative rcall/rjmp. */
1805 case R_AVR_CALL:
1807 bfd_vma value = symval + irel->r_addend;
1808 bfd_vma dot, gap;
1809 int distance_short_enough = 0;
1811 /* Get the address of this instruction. */
1812 dot = (sec->output_section->vma
1813 + sec->output_offset + irel->r_offset);
1815 /* Compute the distance from this insn to the branch target. */
1816 gap = value - dot;
1818 /* If the distance is within -4094..+4098 inclusive, then we can
1819 relax this jump/call. +4098 because the call/jump target
1820 will be closer after the relaxation. */
1821 if ((int) gap >= -4094 && (int) gap <= 4098)
1822 distance_short_enough = 1;
1824 /* Here we handle the wrap-around case. E.g. for a 16k device
1825 we could use a rjmp to jump from address 0x100 to 0x3d00!
1826 In order to make this work properly, we need to fill the
1827 vaiable avr_pc_wrap_around with the appropriate value.
1828 I.e. 0x4000 for a 16k device. */
1830 /* Shrinking the code size makes the gaps larger in the
1831 case of wrap-arounds. So we use a heuristical safety
1832 margin to avoid that during relax the distance gets
1833 again too large for the short jumps. Let's assume
1834 a typical code-size reduction due to relax for a
1835 16k device of 600 bytes. So let's use twice the
1836 typical value as safety margin. */
1837 int rgap;
1838 int safety_margin;
1840 int assumed_shrink = 600;
1841 if (avr_pc_wrap_around > 0x4000)
1842 assumed_shrink = 900;
1844 safety_margin = 2 * assumed_shrink;
1846 rgap = avr_relative_distance_considering_wrap_around (gap);
1848 if (rgap >= (-4092 + safety_margin)
1849 && rgap <= (4094 - safety_margin))
1850 distance_short_enough = 1;
1853 if (distance_short_enough)
1855 unsigned char code_msb;
1856 unsigned char code_lsb;
1858 if (debug_relax)
1859 printf ("shrinking jump/call instruction at address 0x%x"
1860 " in section %s\n\n",
1861 (int) dot, sec->name);
1863 /* Note that we've changed the relocs, section contents,
1864 etc. */
1865 elf_section_data (sec)->relocs = internal_relocs;
1866 elf_section_data (sec)->this_hdr.contents = contents;
1867 symtab_hdr->contents = (unsigned char *) isymbuf;
1869 /* Get the instruction code for relaxing. */
1870 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset);
1871 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1873 /* Mask out the relocation bits. */
1874 code_msb &= 0x94;
1875 code_lsb &= 0x0E;
1876 if (code_msb == 0x94 && code_lsb == 0x0E)
1878 /* we are changing call -> rcall . */
1879 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1880 bfd_put_8 (abfd, 0xD0, contents + irel->r_offset + 1);
1882 else if (code_msb == 0x94 && code_lsb == 0x0C)
1884 /* we are changeing jump -> rjmp. */
1885 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1886 bfd_put_8 (abfd, 0xC0, contents + irel->r_offset + 1);
1888 else
1889 abort ();
1891 /* Fix the relocation's type. */
1892 irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
1893 R_AVR_13_PCREL);
1895 /* Check for the vector section. There we don't want to
1896 modify the ordering! */
1898 if (!strcmp (sec->name,".vectors")
1899 || !strcmp (sec->name,".jumptables"))
1901 /* Let's insert a nop. */
1902 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
1903 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 3);
1905 else
1907 /* Delete two bytes of data. */
1908 if (!elf32_avr_relax_delete_bytes (abfd, sec,
1909 irel->r_offset + 2, 2))
1910 goto error_return;
1912 /* That will change things, so, we should relax again.
1913 Note that this is not required, and it may be slow. */
1914 *again = TRUE;
1919 default:
1921 unsigned char code_msb;
1922 unsigned char code_lsb;
1923 bfd_vma dot;
1925 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1926 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset + 0);
1928 /* Get the address of this instruction. */
1929 dot = (sec->output_section->vma
1930 + sec->output_offset + irel->r_offset);
1932 /* Here we look for rcall/ret or call/ret sequences that could be
1933 safely replaced by rjmp/ret or jmp/ret. */
1934 if (((code_msb & 0xf0) == 0xd0)
1935 && avr_replace_call_ret_sequences)
1937 /* This insn is a rcall. */
1938 unsigned char next_insn_msb = 0;
1939 unsigned char next_insn_lsb = 0;
1941 if (irel->r_offset + 3 < sec->size)
1943 next_insn_msb =
1944 bfd_get_8 (abfd, contents + irel->r_offset + 3);
1945 next_insn_lsb =
1946 bfd_get_8 (abfd, contents + irel->r_offset + 2);
1949 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1951 /* The next insn is a ret. We now convert the rcall insn
1952 into a rjmp instruction. */
1953 code_msb &= 0xef;
1954 bfd_put_8 (abfd, code_msb, contents + irel->r_offset + 1);
1955 if (debug_relax)
1956 printf ("converted rcall/ret sequence at address 0x%x"
1957 " into rjmp/ret sequence. Section is %s\n\n",
1958 (int) dot, sec->name);
1959 *again = TRUE;
1960 break;
1963 else if ((0x94 == (code_msb & 0xfe))
1964 && (0x0e == (code_lsb & 0x0e))
1965 && avr_replace_call_ret_sequences)
1967 /* This insn is a call. */
1968 unsigned char next_insn_msb = 0;
1969 unsigned char next_insn_lsb = 0;
1971 if (irel->r_offset + 5 < sec->size)
1973 next_insn_msb =
1974 bfd_get_8 (abfd, contents + irel->r_offset + 5);
1975 next_insn_lsb =
1976 bfd_get_8 (abfd, contents + irel->r_offset + 4);
1979 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1981 /* The next insn is a ret. We now convert the call insn
1982 into a jmp instruction. */
1984 code_lsb &= 0xfd;
1985 bfd_put_8 (abfd, code_lsb, contents + irel->r_offset);
1986 if (debug_relax)
1987 printf ("converted call/ret sequence at address 0x%x"
1988 " into jmp/ret sequence. Section is %s\n\n",
1989 (int) dot, sec->name);
1990 *again = TRUE;
1991 break;
1994 else if ((0xc0 == (code_msb & 0xf0))
1995 || ((0x94 == (code_msb & 0xfe))
1996 && (0x0c == (code_lsb & 0x0e))))
1998 /* This insn is a rjmp or a jmp. */
1999 unsigned char next_insn_msb = 0;
2000 unsigned char next_insn_lsb = 0;
2001 int insn_size;
2003 if (0xc0 == (code_msb & 0xf0))
2004 insn_size = 2; /* rjmp insn */
2005 else
2006 insn_size = 4; /* jmp insn */
2008 if (irel->r_offset + insn_size + 1 < sec->size)
2010 next_insn_msb =
2011 bfd_get_8 (abfd, contents + irel->r_offset
2012 + insn_size + 1);
2013 next_insn_lsb =
2014 bfd_get_8 (abfd, contents + irel->r_offset
2015 + insn_size);
2018 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
2020 /* The next insn is a ret. We possibly could delete
2021 this ret. First we need to check for preceding
2022 sbis/sbic/sbrs or cpse "skip" instructions. */
2024 int there_is_preceding_non_skip_insn = 1;
2025 bfd_vma address_of_ret;
2027 address_of_ret = dot + insn_size;
2029 if (debug_relax && (insn_size == 2))
2030 printf ("found rjmp / ret sequence at address 0x%x\n",
2031 (int) dot);
2032 if (debug_relax && (insn_size == 4))
2033 printf ("found jmp / ret sequence at address 0x%x\n",
2034 (int) dot);
2036 /* We have to make sure that there is a preceding insn. */
2037 if (irel->r_offset >= 2)
2039 unsigned char preceding_msb;
2040 unsigned char preceding_lsb;
2042 preceding_msb =
2043 bfd_get_8 (abfd, contents + irel->r_offset - 1);
2044 preceding_lsb =
2045 bfd_get_8 (abfd, contents + irel->r_offset - 2);
2047 /* sbic. */
2048 if (0x99 == preceding_msb)
2049 there_is_preceding_non_skip_insn = 0;
2051 /* sbis. */
2052 if (0x9b == preceding_msb)
2053 there_is_preceding_non_skip_insn = 0;
2055 /* sbrc */
2056 if ((0xfc == (preceding_msb & 0xfe)
2057 && (0x00 == (preceding_lsb & 0x08))))
2058 there_is_preceding_non_skip_insn = 0;
2060 /* sbrs */
2061 if ((0xfe == (preceding_msb & 0xfe)
2062 && (0x00 == (preceding_lsb & 0x08))))
2063 there_is_preceding_non_skip_insn = 0;
2065 /* cpse */
2066 if (0x10 == (preceding_msb & 0xfc))
2067 there_is_preceding_non_skip_insn = 0;
2069 if (there_is_preceding_non_skip_insn == 0)
2070 if (debug_relax)
2071 printf ("preceding skip insn prevents deletion of"
2072 " ret insn at Addy 0x%x in section %s\n",
2073 (int) dot + 2, sec->name);
2075 else
2077 /* There is no previous instruction. */
2078 there_is_preceding_non_skip_insn = 0;
2081 if (there_is_preceding_non_skip_insn)
2083 /* We now only have to make sure that there is no
2084 local label defined at the address of the ret
2085 instruction and that there is no local relocation
2086 in this section pointing to the ret. */
2088 int deleting_ret_is_safe = 1;
2089 unsigned int section_offset_of_ret_insn =
2090 irel->r_offset + insn_size;
2091 Elf_Internal_Sym *isym, *isymend;
2092 unsigned int sec_shndx;
2094 sec_shndx =
2095 _bfd_elf_section_from_bfd_section (abfd, sec);
2097 /* Check for local symbols. */
2098 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
2099 isymend = isym + symtab_hdr->sh_info;
2100 /* PR 6019: There may not be any local symbols. */
2101 for (; isym != NULL && isym < isymend; isym++)
2103 if (isym->st_value == section_offset_of_ret_insn
2104 && isym->st_shndx == sec_shndx)
2106 deleting_ret_is_safe = 0;
2107 if (debug_relax)
2108 printf ("local label prevents deletion of ret "
2109 "insn at address 0x%x\n",
2110 (int) dot + insn_size);
2114 /* Now check for global symbols. */
2116 int symcount;
2117 struct elf_link_hash_entry **sym_hashes;
2118 struct elf_link_hash_entry **end_hashes;
2120 symcount = (symtab_hdr->sh_size
2121 / sizeof (Elf32_External_Sym)
2122 - symtab_hdr->sh_info);
2123 sym_hashes = elf_sym_hashes (abfd);
2124 end_hashes = sym_hashes + symcount;
2125 for (; sym_hashes < end_hashes; sym_hashes++)
2127 struct elf_link_hash_entry *sym_hash =
2128 *sym_hashes;
2129 if ((sym_hash->root.type == bfd_link_hash_defined
2130 || sym_hash->root.type ==
2131 bfd_link_hash_defweak)
2132 && sym_hash->root.u.def.section == sec
2133 && sym_hash->root.u.def.value == section_offset_of_ret_insn)
2135 deleting_ret_is_safe = 0;
2136 if (debug_relax)
2137 printf ("global label prevents deletion of "
2138 "ret insn at address 0x%x\n",
2139 (int) dot + insn_size);
2143 /* Now we check for relocations pointing to ret. */
2145 Elf_Internal_Rela *rel;
2146 Elf_Internal_Rela *relend;
2148 relend = elf_section_data (sec)->relocs
2149 + sec->reloc_count;
2151 for (rel = elf_section_data (sec)->relocs;
2152 rel < relend; rel++)
2154 bfd_vma reloc_target = 0;
2156 /* Read this BFD's local symbols if we haven't
2157 done so already. */
2158 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
2160 isymbuf = (Elf_Internal_Sym *)
2161 symtab_hdr->contents;
2162 if (isymbuf == NULL)
2163 isymbuf = bfd_elf_get_elf_syms
2164 (abfd,
2165 symtab_hdr,
2166 symtab_hdr->sh_info, 0,
2167 NULL, NULL, NULL);
2168 if (isymbuf == NULL)
2169 break;
2172 /* Get the value of the symbol referred to
2173 by the reloc. */
2174 if (ELF32_R_SYM (rel->r_info)
2175 < symtab_hdr->sh_info)
2177 /* A local symbol. */
2178 asection *sym_sec;
2180 isym = isymbuf
2181 + ELF32_R_SYM (rel->r_info);
2182 sym_sec = bfd_section_from_elf_index
2183 (abfd, isym->st_shndx);
2184 symval = isym->st_value;
2186 /* If the reloc is absolute, it will not
2187 have a symbol or section associated
2188 with it. */
2190 if (sym_sec)
2192 symval +=
2193 sym_sec->output_section->vma
2194 + sym_sec->output_offset;
2195 reloc_target = symval + rel->r_addend;
2197 else
2199 reloc_target = symval + rel->r_addend;
2200 /* Reference symbol is absolute. */
2203 /* else ... reference symbol is extern. */
2205 if (address_of_ret == reloc_target)
2207 deleting_ret_is_safe = 0;
2208 if (debug_relax)
2209 printf ("ret from "
2210 "rjmp/jmp ret sequence at address"
2211 " 0x%x could not be deleted. ret"
2212 " is target of a relocation.\n",
2213 (int) address_of_ret);
2218 if (deleting_ret_is_safe)
2220 if (debug_relax)
2221 printf ("unreachable ret instruction "
2222 "at address 0x%x deleted.\n",
2223 (int) dot + insn_size);
2225 /* Delete two bytes of data. */
2226 if (!elf32_avr_relax_delete_bytes (abfd, sec,
2227 irel->r_offset + insn_size, 2))
2228 goto error_return;
2230 /* That will change things, so, we should relax
2231 again. Note that this is not required, and it
2232 may be slow. */
2233 *again = TRUE;
2234 break;
2240 break;
2245 if (contents != NULL
2246 && elf_section_data (sec)->this_hdr.contents != contents)
2248 if (! link_info->keep_memory)
2249 free (contents);
2250 else
2252 /* Cache the section contents for elf_link_input_bfd. */
2253 elf_section_data (sec)->this_hdr.contents = contents;
2257 if (internal_relocs != NULL
2258 && elf_section_data (sec)->relocs != internal_relocs)
2259 free (internal_relocs);
2261 return TRUE;
2263 error_return:
2264 if (isymbuf != NULL
2265 && symtab_hdr->contents != (unsigned char *) isymbuf)
2266 free (isymbuf);
2267 if (contents != NULL
2268 && elf_section_data (sec)->this_hdr.contents != contents)
2269 free (contents);
2270 if (internal_relocs != NULL
2271 && elf_section_data (sec)->relocs != internal_relocs)
2272 free (internal_relocs);
2274 return FALSE;
2277 /* This is a version of bfd_generic_get_relocated_section_contents
2278 which uses elf32_avr_relocate_section.
2280 For avr it's essentially a cut and paste taken from the H8300 port.
2281 The author of the relaxation support patch for avr had absolutely no
2282 clue what is happening here but found out that this part of the code
2283 seems to be important. */
2285 static bfd_byte *
2286 elf32_avr_get_relocated_section_contents (bfd *output_bfd,
2287 struct bfd_link_info *link_info,
2288 struct bfd_link_order *link_order,
2289 bfd_byte *data,
2290 bfd_boolean relocatable,
2291 asymbol **symbols)
2293 Elf_Internal_Shdr *symtab_hdr;
2294 asection *input_section = link_order->u.indirect.section;
2295 bfd *input_bfd = input_section->owner;
2296 asection **sections = NULL;
2297 Elf_Internal_Rela *internal_relocs = NULL;
2298 Elf_Internal_Sym *isymbuf = NULL;
2300 /* We only need to handle the case of relaxing, or of having a
2301 particular set of section contents, specially. */
2302 if (relocatable
2303 || elf_section_data (input_section)->this_hdr.contents == NULL)
2304 return bfd_generic_get_relocated_section_contents (output_bfd, link_info,
2305 link_order, data,
2306 relocatable,
2307 symbols);
2308 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2310 memcpy (data, elf_section_data (input_section)->this_hdr.contents,
2311 (size_t) input_section->size);
2313 if ((input_section->flags & SEC_RELOC) != 0
2314 && input_section->reloc_count > 0)
2316 asection **secpp;
2317 Elf_Internal_Sym *isym, *isymend;
2318 bfd_size_type amt;
2320 internal_relocs = (_bfd_elf_link_read_relocs
2321 (input_bfd, input_section, NULL, NULL, FALSE));
2322 if (internal_relocs == NULL)
2323 goto error_return;
2325 if (symtab_hdr->sh_info != 0)
2327 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
2328 if (isymbuf == NULL)
2329 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2330 symtab_hdr->sh_info, 0,
2331 NULL, NULL, NULL);
2332 if (isymbuf == NULL)
2333 goto error_return;
2336 amt = symtab_hdr->sh_info;
2337 amt *= sizeof (asection *);
2338 sections = bfd_malloc (amt);
2339 if (sections == NULL && amt != 0)
2340 goto error_return;
2342 isymend = isymbuf + symtab_hdr->sh_info;
2343 for (isym = isymbuf, secpp = sections; isym < isymend; ++isym, ++secpp)
2345 asection *isec;
2347 if (isym->st_shndx == SHN_UNDEF)
2348 isec = bfd_und_section_ptr;
2349 else if (isym->st_shndx == SHN_ABS)
2350 isec = bfd_abs_section_ptr;
2351 else if (isym->st_shndx == SHN_COMMON)
2352 isec = bfd_com_section_ptr;
2353 else
2354 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
2356 *secpp = isec;
2359 if (! elf32_avr_relocate_section (output_bfd, link_info, input_bfd,
2360 input_section, data, internal_relocs,
2361 isymbuf, sections))
2362 goto error_return;
2364 if (sections != NULL)
2365 free (sections);
2366 if (isymbuf != NULL
2367 && symtab_hdr->contents != (unsigned char *) isymbuf)
2368 free (isymbuf);
2369 if (elf_section_data (input_section)->relocs != internal_relocs)
2370 free (internal_relocs);
2373 return data;
2375 error_return:
2376 if (sections != NULL)
2377 free (sections);
2378 if (isymbuf != NULL
2379 && symtab_hdr->contents != (unsigned char *) isymbuf)
2380 free (isymbuf);
2381 if (internal_relocs != NULL
2382 && elf_section_data (input_section)->relocs != internal_relocs)
2383 free (internal_relocs);
2384 return NULL;
2388 /* Determines the hash entry name for a particular reloc. It consists of
2389 the identifier of the symbol section and the added reloc addend and
2390 symbol offset relative to the section the symbol is attached to. */
2392 static char *
2393 avr_stub_name (const asection *symbol_section,
2394 const bfd_vma symbol_offset,
2395 const Elf_Internal_Rela *rela)
2397 char *stub_name;
2398 bfd_size_type len;
2400 len = 8 + 1 + 8 + 1 + 1;
2401 stub_name = bfd_malloc (len);
2403 sprintf (stub_name, "%08x+%08x",
2404 symbol_section->id & 0xffffffff,
2405 (unsigned int) ((rela->r_addend & 0xffffffff) + symbol_offset));
2407 return stub_name;
2411 /* Add a new stub entry to the stub hash. Not all fields of the new
2412 stub entry are initialised. */
2414 static struct elf32_avr_stub_hash_entry *
2415 avr_add_stub (const char *stub_name,
2416 struct elf32_avr_link_hash_table *htab)
2418 struct elf32_avr_stub_hash_entry *hsh;
2420 /* Enter this entry into the linker stub hash table. */
2421 hsh = avr_stub_hash_lookup (&htab->bstab, stub_name, TRUE, FALSE);
2423 if (hsh == NULL)
2425 (*_bfd_error_handler) (_("%B: cannot create stub entry %s"),
2426 NULL, stub_name);
2427 return NULL;
2430 hsh->stub_offset = 0;
2431 return hsh;
2434 /* We assume that there is already space allocated for the stub section
2435 contents and that before building the stubs the section size is
2436 initialized to 0. We assume that within the stub hash table entry,
2437 the absolute position of the jmp target has been written in the
2438 target_value field. We write here the offset of the generated jmp insn
2439 relative to the trampoline section start to the stub_offset entry in
2440 the stub hash table entry. */
2442 static bfd_boolean
2443 avr_build_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2445 struct elf32_avr_stub_hash_entry *hsh;
2446 struct bfd_link_info *info;
2447 struct elf32_avr_link_hash_table *htab;
2448 bfd *stub_bfd;
2449 bfd_byte *loc;
2450 bfd_vma target;
2451 bfd_vma starget;
2453 /* Basic opcode */
2454 bfd_vma jmp_insn = 0x0000940c;
2456 /* Massage our args to the form they really have. */
2457 hsh = avr_stub_hash_entry (bh);
2459 if (!hsh->is_actually_needed)
2460 return TRUE;
2462 info = (struct bfd_link_info *) in_arg;
2464 htab = avr_link_hash_table (info);
2465 if (htab == NULL)
2466 return FALSE;
2468 target = hsh->target_value;
2470 /* Make a note of the offset within the stubs for this entry. */
2471 hsh->stub_offset = htab->stub_sec->size;
2472 loc = htab->stub_sec->contents + hsh->stub_offset;
2474 stub_bfd = htab->stub_sec->owner;
2476 if (debug_stubs)
2477 printf ("Building one Stub. Address: 0x%x, Offset: 0x%x\n",
2478 (unsigned int) target,
2479 (unsigned int) hsh->stub_offset);
2481 /* We now have to add the information on the jump target to the bare
2482 opcode bits already set in jmp_insn. */
2484 /* Check for the alignment of the address. */
2485 if (target & 1)
2486 return FALSE;
2488 starget = target >> 1;
2489 jmp_insn |= ((starget & 0x10000) | ((starget << 3) & 0x1f00000)) >> 16;
2490 bfd_put_16 (stub_bfd, jmp_insn, loc);
2491 bfd_put_16 (stub_bfd, (bfd_vma) starget & 0xffff, loc + 2);
2493 htab->stub_sec->size += 4;
2495 /* Now add the entries in the address mapping table if there is still
2496 space left. */
2498 unsigned int nr;
2500 nr = htab->amt_entry_cnt + 1;
2501 if (nr <= htab->amt_max_entry_cnt)
2503 htab->amt_entry_cnt = nr;
2505 htab->amt_stub_offsets[nr - 1] = hsh->stub_offset;
2506 htab->amt_destination_addr[nr - 1] = target;
2510 return TRUE;
2513 static bfd_boolean
2514 avr_mark_stub_not_to_be_necessary (struct bfd_hash_entry *bh,
2515 void *in_arg ATTRIBUTE_UNUSED)
2517 struct elf32_avr_stub_hash_entry *hsh;
2519 hsh = avr_stub_hash_entry (bh);
2520 hsh->is_actually_needed = FALSE;
2522 return TRUE;
2525 static bfd_boolean
2526 avr_size_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2528 struct elf32_avr_stub_hash_entry *hsh;
2529 struct elf32_avr_link_hash_table *htab;
2530 int size;
2532 /* Massage our args to the form they really have. */
2533 hsh = avr_stub_hash_entry (bh);
2534 htab = in_arg;
2536 if (hsh->is_actually_needed)
2537 size = 4;
2538 else
2539 size = 0;
2541 htab->stub_sec->size += size;
2542 return TRUE;
2545 void
2546 elf32_avr_setup_params (struct bfd_link_info *info,
2547 bfd *avr_stub_bfd,
2548 asection *avr_stub_section,
2549 bfd_boolean no_stubs,
2550 bfd_boolean deb_stubs,
2551 bfd_boolean deb_relax,
2552 bfd_vma pc_wrap_around,
2553 bfd_boolean call_ret_replacement)
2555 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2557 if (htab == NULL)
2558 return;
2559 htab->stub_sec = avr_stub_section;
2560 htab->stub_bfd = avr_stub_bfd;
2561 htab->no_stubs = no_stubs;
2563 debug_relax = deb_relax;
2564 debug_stubs = deb_stubs;
2565 avr_pc_wrap_around = pc_wrap_around;
2566 avr_replace_call_ret_sequences = call_ret_replacement;
2570 /* Set up various things so that we can make a list of input sections
2571 for each output section included in the link. Returns -1 on error,
2572 0 when no stubs will be needed, and 1 on success. It also sets
2573 information on the stubs bfd and the stub section in the info
2574 struct. */
2577 elf32_avr_setup_section_lists (bfd *output_bfd,
2578 struct bfd_link_info *info)
2580 bfd *input_bfd;
2581 unsigned int bfd_count;
2582 int top_id, top_index;
2583 asection *section;
2584 asection **input_list, **list;
2585 bfd_size_type amt;
2586 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2588 if (htab == NULL || htab->no_stubs)
2589 return 0;
2591 /* Count the number of input BFDs and find the top input section id. */
2592 for (input_bfd = info->input_bfds, bfd_count = 0, top_id = 0;
2593 input_bfd != NULL;
2594 input_bfd = input_bfd->link_next)
2596 bfd_count += 1;
2597 for (section = input_bfd->sections;
2598 section != NULL;
2599 section = section->next)
2600 if (top_id < section->id)
2601 top_id = section->id;
2604 htab->bfd_count = bfd_count;
2606 /* We can't use output_bfd->section_count here to find the top output
2607 section index as some sections may have been removed, and
2608 strip_excluded_output_sections doesn't renumber the indices. */
2609 for (section = output_bfd->sections, top_index = 0;
2610 section != NULL;
2611 section = section->next)
2612 if (top_index < section->index)
2613 top_index = section->index;
2615 htab->top_index = top_index;
2616 amt = sizeof (asection *) * (top_index + 1);
2617 input_list = bfd_malloc (amt);
2618 htab->input_list = input_list;
2619 if (input_list == NULL)
2620 return -1;
2622 /* For sections we aren't interested in, mark their entries with a
2623 value we can check later. */
2624 list = input_list + top_index;
2626 *list = bfd_abs_section_ptr;
2627 while (list-- != input_list);
2629 for (section = output_bfd->sections;
2630 section != NULL;
2631 section = section->next)
2632 if ((section->flags & SEC_CODE) != 0)
2633 input_list[section->index] = NULL;
2635 return 1;
2639 /* Read in all local syms for all input bfds, and create hash entries
2640 for export stubs if we are building a multi-subspace shared lib.
2641 Returns -1 on error, 0 otherwise. */
2643 static int
2644 get_local_syms (bfd *input_bfd, struct bfd_link_info *info)
2646 unsigned int bfd_indx;
2647 Elf_Internal_Sym *local_syms, **all_local_syms;
2648 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2649 bfd_size_type amt;
2651 if (htab == NULL)
2652 return -1;
2654 /* We want to read in symbol extension records only once. To do this
2655 we need to read in the local symbols in parallel and save them for
2656 later use; so hold pointers to the local symbols in an array. */
2657 amt = sizeof (Elf_Internal_Sym *) * htab->bfd_count;
2658 all_local_syms = bfd_zmalloc (amt);
2659 htab->all_local_syms = all_local_syms;
2660 if (all_local_syms == NULL)
2661 return -1;
2663 /* Walk over all the input BFDs, swapping in local symbols.
2664 If we are creating a shared library, create hash entries for the
2665 export stubs. */
2666 for (bfd_indx = 0;
2667 input_bfd != NULL;
2668 input_bfd = input_bfd->link_next, bfd_indx++)
2670 Elf_Internal_Shdr *symtab_hdr;
2672 /* We'll need the symbol table in a second. */
2673 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2674 if (symtab_hdr->sh_info == 0)
2675 continue;
2677 /* We need an array of the local symbols attached to the input bfd. */
2678 local_syms = (Elf_Internal_Sym *) symtab_hdr->contents;
2679 if (local_syms == NULL)
2681 local_syms = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2682 symtab_hdr->sh_info, 0,
2683 NULL, NULL, NULL);
2684 /* Cache them for elf_link_input_bfd. */
2685 symtab_hdr->contents = (unsigned char *) local_syms;
2687 if (local_syms == NULL)
2688 return -1;
2690 all_local_syms[bfd_indx] = local_syms;
2693 return 0;
2696 #define ADD_DUMMY_STUBS_FOR_DEBUGGING 0
2698 bfd_boolean
2699 elf32_avr_size_stubs (bfd *output_bfd,
2700 struct bfd_link_info *info,
2701 bfd_boolean is_prealloc_run)
2703 struct elf32_avr_link_hash_table *htab;
2704 int stub_changed = 0;
2706 htab = avr_link_hash_table (info);
2707 if (htab == NULL)
2708 return FALSE;
2710 /* At this point we initialize htab->vector_base
2711 To the start of the text output section. */
2712 htab->vector_base = htab->stub_sec->output_section->vma;
2714 if (get_local_syms (info->input_bfds, info))
2716 if (htab->all_local_syms)
2717 goto error_ret_free_local;
2718 return FALSE;
2721 if (ADD_DUMMY_STUBS_FOR_DEBUGGING)
2723 struct elf32_avr_stub_hash_entry *test;
2725 test = avr_add_stub ("Hugo",htab);
2726 test->target_value = 0x123456;
2727 test->stub_offset = 13;
2729 test = avr_add_stub ("Hugo2",htab);
2730 test->target_value = 0x84210;
2731 test->stub_offset = 14;
2734 while (1)
2736 bfd *input_bfd;
2737 unsigned int bfd_indx;
2739 /* We will have to re-generate the stub hash table each time anything
2740 in memory has changed. */
2742 bfd_hash_traverse (&htab->bstab, avr_mark_stub_not_to_be_necessary, htab);
2743 for (input_bfd = info->input_bfds, bfd_indx = 0;
2744 input_bfd != NULL;
2745 input_bfd = input_bfd->link_next, bfd_indx++)
2747 Elf_Internal_Shdr *symtab_hdr;
2748 asection *section;
2749 Elf_Internal_Sym *local_syms;
2751 /* We'll need the symbol table in a second. */
2752 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2753 if (symtab_hdr->sh_info == 0)
2754 continue;
2756 local_syms = htab->all_local_syms[bfd_indx];
2758 /* Walk over each section attached to the input bfd. */
2759 for (section = input_bfd->sections;
2760 section != NULL;
2761 section = section->next)
2763 Elf_Internal_Rela *internal_relocs, *irelaend, *irela;
2765 /* If there aren't any relocs, then there's nothing more
2766 to do. */
2767 if ((section->flags & SEC_RELOC) == 0
2768 || section->reloc_count == 0)
2769 continue;
2771 /* If this section is a link-once section that will be
2772 discarded, then don't create any stubs. */
2773 if (section->output_section == NULL
2774 || section->output_section->owner != output_bfd)
2775 continue;
2777 /* Get the relocs. */
2778 internal_relocs
2779 = _bfd_elf_link_read_relocs (input_bfd, section, NULL, NULL,
2780 info->keep_memory);
2781 if (internal_relocs == NULL)
2782 goto error_ret_free_local;
2784 /* Now examine each relocation. */
2785 irela = internal_relocs;
2786 irelaend = irela + section->reloc_count;
2787 for (; irela < irelaend; irela++)
2789 unsigned int r_type, r_indx;
2790 struct elf32_avr_stub_hash_entry *hsh;
2791 asection *sym_sec;
2792 bfd_vma sym_value;
2793 bfd_vma destination;
2794 struct elf_link_hash_entry *hh;
2795 char *stub_name;
2797 r_type = ELF32_R_TYPE (irela->r_info);
2798 r_indx = ELF32_R_SYM (irela->r_info);
2800 /* Only look for 16 bit GS relocs. No other reloc will need a
2801 stub. */
2802 if (!((r_type == R_AVR_16_PM)
2803 || (r_type == R_AVR_LO8_LDI_GS)
2804 || (r_type == R_AVR_HI8_LDI_GS)))
2805 continue;
2807 /* Now determine the call target, its name, value,
2808 section. */
2809 sym_sec = NULL;
2810 sym_value = 0;
2811 destination = 0;
2812 hh = NULL;
2813 if (r_indx < symtab_hdr->sh_info)
2815 /* It's a local symbol. */
2816 Elf_Internal_Sym *sym;
2817 Elf_Internal_Shdr *hdr;
2818 unsigned int shndx;
2820 sym = local_syms + r_indx;
2821 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2822 sym_value = sym->st_value;
2823 shndx = sym->st_shndx;
2824 if (shndx < elf_numsections (input_bfd))
2826 hdr = elf_elfsections (input_bfd)[shndx];
2827 sym_sec = hdr->bfd_section;
2828 destination = (sym_value + irela->r_addend
2829 + sym_sec->output_offset
2830 + sym_sec->output_section->vma);
2833 else
2835 /* It's an external symbol. */
2836 int e_indx;
2838 e_indx = r_indx - symtab_hdr->sh_info;
2839 hh = elf_sym_hashes (input_bfd)[e_indx];
2841 while (hh->root.type == bfd_link_hash_indirect
2842 || hh->root.type == bfd_link_hash_warning)
2843 hh = (struct elf_link_hash_entry *)
2844 (hh->root.u.i.link);
2846 if (hh->root.type == bfd_link_hash_defined
2847 || hh->root.type == bfd_link_hash_defweak)
2849 sym_sec = hh->root.u.def.section;
2850 sym_value = hh->root.u.def.value;
2851 if (sym_sec->output_section != NULL)
2852 destination = (sym_value + irela->r_addend
2853 + sym_sec->output_offset
2854 + sym_sec->output_section->vma);
2856 else if (hh->root.type == bfd_link_hash_undefweak)
2858 if (! info->shared)
2859 continue;
2861 else if (hh->root.type == bfd_link_hash_undefined)
2863 if (! (info->unresolved_syms_in_objects == RM_IGNORE
2864 && (ELF_ST_VISIBILITY (hh->other)
2865 == STV_DEFAULT)))
2866 continue;
2868 else
2870 bfd_set_error (bfd_error_bad_value);
2872 error_ret_free_internal:
2873 if (elf_section_data (section)->relocs == NULL)
2874 free (internal_relocs);
2875 goto error_ret_free_local;
2879 if (! avr_stub_is_required_for_16_bit_reloc
2880 (destination - htab->vector_base))
2882 if (!is_prealloc_run)
2883 /* We are having a reloc that does't need a stub. */
2884 continue;
2886 /* We don't right now know if a stub will be needed.
2887 Let's rather be on the safe side. */
2890 /* Get the name of this stub. */
2891 stub_name = avr_stub_name (sym_sec, sym_value, irela);
2893 if (!stub_name)
2894 goto error_ret_free_internal;
2897 hsh = avr_stub_hash_lookup (&htab->bstab,
2898 stub_name,
2899 FALSE, FALSE);
2900 if (hsh != NULL)
2902 /* The proper stub has already been created. Mark it
2903 to be used and write the possibly changed destination
2904 value. */
2905 hsh->is_actually_needed = TRUE;
2906 hsh->target_value = destination;
2907 free (stub_name);
2908 continue;
2911 hsh = avr_add_stub (stub_name, htab);
2912 if (hsh == NULL)
2914 free (stub_name);
2915 goto error_ret_free_internal;
2918 hsh->is_actually_needed = TRUE;
2919 hsh->target_value = destination;
2921 if (debug_stubs)
2922 printf ("Adding stub with destination 0x%x to the"
2923 " hash table.\n", (unsigned int) destination);
2924 if (debug_stubs)
2925 printf ("(Pre-Alloc run: %i)\n", is_prealloc_run);
2927 stub_changed = TRUE;
2930 /* We're done with the internal relocs, free them. */
2931 if (elf_section_data (section)->relocs == NULL)
2932 free (internal_relocs);
2936 /* Re-Calculate the number of needed stubs. */
2937 htab->stub_sec->size = 0;
2938 bfd_hash_traverse (&htab->bstab, avr_size_one_stub, htab);
2940 if (!stub_changed)
2941 break;
2943 stub_changed = FALSE;
2946 free (htab->all_local_syms);
2947 return TRUE;
2949 error_ret_free_local:
2950 free (htab->all_local_syms);
2951 return FALSE;
2955 /* Build all the stubs associated with the current output file. The
2956 stubs are kept in a hash table attached to the main linker hash
2957 table. We also set up the .plt entries for statically linked PIC
2958 functions here. This function is called via hppaelf_finish in the
2959 linker. */
2961 bfd_boolean
2962 elf32_avr_build_stubs (struct bfd_link_info *info)
2964 asection *stub_sec;
2965 struct bfd_hash_table *table;
2966 struct elf32_avr_link_hash_table *htab;
2967 bfd_size_type total_size = 0;
2969 htab = avr_link_hash_table (info);
2970 if (htab == NULL)
2971 return FALSE;
2973 /* In case that there were several stub sections: */
2974 for (stub_sec = htab->stub_bfd->sections;
2975 stub_sec != NULL;
2976 stub_sec = stub_sec->next)
2978 bfd_size_type size;
2980 /* Allocate memory to hold the linker stubs. */
2981 size = stub_sec->size;
2982 total_size += size;
2984 stub_sec->contents = bfd_zalloc (htab->stub_bfd, size);
2985 if (stub_sec->contents == NULL && size != 0)
2986 return FALSE;
2987 stub_sec->size = 0;
2990 /* Allocate memory for the adress mapping table. */
2991 htab->amt_entry_cnt = 0;
2992 htab->amt_max_entry_cnt = total_size / 4;
2993 htab->amt_stub_offsets = bfd_malloc (sizeof (bfd_vma)
2994 * htab->amt_max_entry_cnt);
2995 htab->amt_destination_addr = bfd_malloc (sizeof (bfd_vma)
2996 * htab->amt_max_entry_cnt );
2998 if (debug_stubs)
2999 printf ("Allocating %i entries in the AMT\n", htab->amt_max_entry_cnt);
3001 /* Build the stubs as directed by the stub hash table. */
3002 table = &htab->bstab;
3003 bfd_hash_traverse (table, avr_build_one_stub, info);
3005 if (debug_stubs)
3006 printf ("Final Stub section Size: %i\n", (int) htab->stub_sec->size);
3008 return TRUE;
3011 #define ELF_ARCH bfd_arch_avr
3012 #define ELF_TARGET_ID AVR_ELF_DATA
3013 #define ELF_MACHINE_CODE EM_AVR
3014 #define ELF_MACHINE_ALT1 EM_AVR_OLD
3015 #define ELF_MAXPAGESIZE 1
3017 #define TARGET_LITTLE_SYM bfd_elf32_avr_vec
3018 #define TARGET_LITTLE_NAME "elf32-avr"
3020 #define bfd_elf32_bfd_link_hash_table_create elf32_avr_link_hash_table_create
3021 #define bfd_elf32_bfd_link_hash_table_free elf32_avr_link_hash_table_free
3023 #define elf_info_to_howto avr_info_to_howto_rela
3024 #define elf_info_to_howto_rel NULL
3025 #define elf_backend_relocate_section elf32_avr_relocate_section
3026 #define elf_backend_can_gc_sections 1
3027 #define elf_backend_rela_normal 1
3028 #define elf_backend_final_write_processing \
3029 bfd_elf_avr_final_write_processing
3030 #define elf_backend_object_p elf32_avr_object_p
3032 #define bfd_elf32_bfd_relax_section elf32_avr_relax_section
3033 #define bfd_elf32_bfd_get_relocated_section_contents \
3034 elf32_avr_get_relocated_section_contents
3036 #include "elf32-target.h"