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Add support for DragonFlyBSD target.
[binutils.git] / bfd / elf32-avr.c
blob1bc40c4403a9ea1dfb7376bfcbd6d8a6bca8a809
1 /* AVR-specific support for 32-bit ELF
2 Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
3 2010 Free Software Foundation, Inc.
4 Contributed by Denis Chertykov <denisc@overta.ru>
5
6 This file is part of BFD, the Binary File Descriptor library.
7
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.
12
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.
17
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. */
22
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"
29
30 /* Enable debugging printout at stdout with this variable. */
31 static bfd_boolean debug_relax = FALSE;
32
33 /* Enable debugging printout at stdout with this variable. */
34 static bfd_boolean debug_stubs = FALSE;
35
36 /* Hash table initialization and handling. Code is taken from the hppa port
37 and adapted to the needs of AVR. */
38
39 /* We use two hash tables to hold information for linking avr objects.
40
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.
44
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. */
48
49 struct elf32_avr_stub_hash_entry
50 {
51 /* Base hash table entry structure. */
52 struct bfd_hash_entry bh_root;
53
54 /* Offset within stub_sec of the beginning of this stub. */
55 bfd_vma stub_offset;
56
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;
60
61 /* This way we could mark stubs to be no longer necessary. */
62 bfd_boolean is_actually_needed;
63 };
64
65 struct elf32_avr_link_hash_table
66 {
67 /* The main hash table. */
68 struct elf_link_hash_table etab;
69
70 /* The stub hash table. */
71 struct bfd_hash_table bstab;
72
73 bfd_boolean no_stubs;
74
75 /* Linker stub bfd. */
76 bfd *stub_bfd;
77
78 /* The stub section. */
79 asection *stub_sec;
80
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;
85
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;
91
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;
102 };
103
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)
109
110 #define avr_stub_hash_entry(ent) \
111 ((struct elf32_avr_stub_hash_entry *)(ent))
112
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)))
116
117 static reloc_howto_type elf_avr_howto_table[] =
118 {
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 */
132
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 */
146
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 */
161
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 */
176
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 */
191
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 */
519 };
520
521 /* Map BFD reloc types to AVR ELF reloc types. */
522
523 struct avr_reloc_map
524 {
525 bfd_reloc_code_real_type bfd_reloc_val;
526 unsigned int elf_reloc_val;
527 };
528
529 static const struct avr_reloc_map avr_reloc_map[] =
530 {
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 }
558 };
559
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.
563
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;
569
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;
574 \f
575 /* Initialize an entry in the stub hash table. */
576
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)
581 {
582 /* Allocate the structure if it has not already been allocated by a
583 subclass. */
584 if (entry == NULL)
585 {
586 entry = bfd_hash_allocate (table,
587 sizeof (struct elf32_avr_stub_hash_entry));
588 if (entry == NULL)
589 return entry;
590 }
591
592 /* Call the allocation method of the superclass. */
593 entry = bfd_hash_newfunc (entry, table, string);
594 if (entry != NULL)
595 {
596 struct elf32_avr_stub_hash_entry *hsh;
597
598 /* Initialize the local fields. */
599 hsh = avr_stub_hash_entry (entry);
600 hsh->stub_offset = 0;
601 hsh->target_value = 0;
602 }
603
604 return entry;
605 }
606
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. */
610
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)
615 {
616 return _bfd_elf_link_hash_newfunc (entry, table, string);
617 }
618
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). */
622
623 static struct bfd_link_hash_table *
624 elf32_avr_link_hash_table_create (bfd *abfd)
625 {
626 struct elf32_avr_link_hash_table *htab;
627 bfd_size_type amt = sizeof (*htab);
628
629 htab = bfd_malloc (amt);
630 if (htab == NULL)
631 return NULL;
632
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))
637 {
638 free (htab);
639 return NULL;
640 }
641
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;
646
647 htab->stub_bfd = NULL;
648 htab->stub_sec = NULL;
649
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;
655
656 return &htab->etab.root;
657 }
658
659 /* Free the derived linker hash table. */
660
661 static void
662 elf32_avr_link_hash_table_free (struct bfd_link_hash_table *btab)
663 {
664 struct elf32_avr_link_hash_table *htab
665 = (struct elf32_avr_link_hash_table *) btab;
666
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);
672
673 bfd_hash_table_free (&htab->bstab);
674 _bfd_generic_link_hash_table_free (btab);
675 }
676
677 /* Calculates the effective distance of a pc relative jump/call. */
678
679 static int
680 avr_relative_distance_considering_wrap_around (unsigned int distance)
681 {
682 unsigned int wrap_around_mask = avr_pc_wrap_around - 1;
683 int dist_with_wrap_around = distance & wrap_around_mask;
684
685 if (dist_with_wrap_around > ((int) (avr_pc_wrap_around >> 1)))
686 dist_with_wrap_around -= avr_pc_wrap_around;
687
688 return dist_with_wrap_around;
689 }
690
691
692 static reloc_howto_type *
693 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
694 bfd_reloc_code_real_type code)
695 {
696 unsigned int i;
697
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];
703
704 return NULL;
705 }
706
707 static reloc_howto_type *
708 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
709 const char *r_name)
710 {
711 unsigned int i;
712
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];
719
720 return NULL;
721 }
722
723 /* Set the howto pointer for an AVR ELF reloc. */
724
725 static void
726 avr_info_to_howto_rela (bfd *abfd ATTRIBUTE_UNUSED,
727 arelent *cache_ptr,
728 Elf_Internal_Rela *dst)
729 {
730 unsigned int r_type;
731
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];
735 }
736
737 static bfd_boolean
738 avr_stub_is_required_for_16_bit_reloc (bfd_vma relocation)
739 {
740 return (relocation >= 0x020000);
741 }
742
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. */
747
748 static bfd_vma
749 avr_get_stub_addr (bfd_vma srel,
750 struct elf32_avr_link_hash_table *htab)
751 {
752 unsigned int sindex;
753 bfd_vma stub_sec_addr =
754 (htab->stub_sec->output_section->vma +
755 htab->stub_sec->output_offset);
756
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;
760
761 /* Return an address that could not be reached by 16 bit relocs. */
762 return 0x020000;
763 }
764
765 /* Perform a single relocation. By default we use the standard BFD
766 routines, but a few relocs, we have to do them ourselves. */
767
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)
776 {
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;
784
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;
788
789 switch (howto->type)
790 {
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);
799
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;
808
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);
817
818 if (srel & 1)
819 return bfd_reloc_outofrange;
820
821 srel = avr_relative_distance_considering_wrap_around (srel);
822
823 /* AVR addresses commands as words. */
824 srel >>= 1;
825
826 /* Check for overflow. */
827 if (srel < -2048 || srel > 2047)
828 {
829 /* Relative distance is too large. */
830
831 /* Always apply WRAPAROUND for avr2, avr25, and avr4. */
832 switch (bfd_get_mach (input_bfd))
833 {
834 case bfd_mach_avr2:
835 case bfd_mach_avr25:
836 case bfd_mach_avr4:
837 break;
838
839 default:
840 return bfd_reloc_overflow;
841 }
842 }
843
844 x = bfd_get_16 (input_bfd, contents);
845 x = (x & 0xf000) | (srel & 0xfff);
846 bfd_put_16 (input_bfd, x, contents);
847 break;
848
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;
856
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;
864
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;
869
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;
881
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;
892
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;
901
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;
910
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;
919
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;
928
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;
938
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;
948
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;
958
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;
965
966 if (use_stubs
967 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
968 {
969 bfd_vma old_srel = srel;
970
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);
979
980 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
981 return bfd_reloc_outofrange;
982 }
983
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;
991
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;
998
999 if (use_stubs
1000 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1001 {
1002 bfd_vma old_srel = srel;
1003
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);
1012
1013 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1014 return bfd_reloc_outofrange;
1015 }
1016
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;
1025
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;
1037
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;
1049
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;
1062
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;
1075
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;
1087
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;
1092
1093 if (use_stubs
1094 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1095 {
1096 bfd_vma old_srel = srel;
1097
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);
1106
1107 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1108 return bfd_reloc_outofrange;
1109 }
1110
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;
1116
1117 default:
1118 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1119 contents, rel->r_offset,
1120 relocation, rel->r_addend);
1121 }
1122
1123 return r;
1124 }
1125
1126 /* Relocate an AVR ELF section. */
1127
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)
1137 {
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);
1143
1144 if (htab == NULL)
1145 return FALSE;
1146
1147 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1148 sym_hashes = elf_sym_hashes (input_bfd);
1149 relend = relocs + input_section->reloc_count;
1150
1151 for (rel = relocs; rel < relend; rel ++)
1152 {
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;
1162
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;
1169
1170 if (r_symndx < symtab_hdr->sh_info)
1171 {
1172 sym = local_syms + r_symndx;
1173 sec = local_sections [r_symndx];
1174 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1175
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;
1179 }
1180 else
1181 {
1182 bfd_boolean unresolved_reloc, warned;
1183
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);
1188
1189 name = h->root.root.string;
1190 }
1191
1192 if (sec != NULL && elf_discarded_section (sec))
1193 RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
1194 rel, relend, howto, contents);
1195
1196 if (info->relocatable)
1197 continue;
1198
1199 r = avr_final_link_relocate (howto, input_bfd, input_section,
1200 contents, rel, relocation, htab);
1201
1202 if (r != bfd_reloc_ok)
1203 {
1204 const char * msg = (const char *) NULL;
1205
1206 switch (r)
1207 {
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;
1214
1215 case bfd_reloc_undefined:
1216 r = info->callbacks->undefined_symbol
1217 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
1218 break;
1219
1220 case bfd_reloc_outofrange:
1221 msg = _("internal error: out of range error");
1222 break;
1223
1224 case bfd_reloc_notsupported:
1225 msg = _("internal error: unsupported relocation error");
1226 break;
1227
1228 case bfd_reloc_dangerous:
1229 msg = _("internal error: dangerous relocation");
1230 break;
1231
1232 default:
1233 msg = _("internal error: unknown error");
1234 break;
1235 }
1236
1237 if (msg)
1238 r = info->callbacks->warning
1239 (info, msg, name, input_bfd, input_section, rel->r_offset);
1240
1241 if (! r)
1242 return FALSE;
1243 }
1244 }
1245
1246 return TRUE;
1247 }
1248
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. */
1252
1253 static void
1254 bfd_elf_avr_final_write_processing (bfd *abfd,
1255 bfd_boolean linker ATTRIBUTE_UNUSED)
1256 {
1257 unsigned long val;
1258
1259 switch (bfd_get_mach (abfd))
1260 {
1261 default:
1262 case bfd_mach_avr2:
1263 val = E_AVR_MACH_AVR2;
1264 break;
1265
1266 case bfd_mach_avr1:
1267 val = E_AVR_MACH_AVR1;
1268 break;
1269
1270 case bfd_mach_avr25:
1271 val = E_AVR_MACH_AVR25;
1272 break;
1273
1274 case bfd_mach_avr3:
1275 val = E_AVR_MACH_AVR3;
1276 break;
1277
1278 case bfd_mach_avr31:
1279 val = E_AVR_MACH_AVR31;
1280 break;
1281
1282 case bfd_mach_avr35:
1283 val = E_AVR_MACH_AVR35;
1284 break;
1285
1286 case bfd_mach_avr4:
1287 val = E_AVR_MACH_AVR4;
1288 break;
1289
1290 case bfd_mach_avr5:
1291 val = E_AVR_MACH_AVR5;
1292 break;
1293
1294 case bfd_mach_avr51:
1295 val = E_AVR_MACH_AVR51;
1296 break;
1297
1298 case bfd_mach_avr6:
1299 val = E_AVR_MACH_AVR6;
1300 break;
1301
1302 case bfd_mach_avrxmega1:
1303 val = E_AVR_MACH_XMEGA1;
1304 break;
1305
1306 case bfd_mach_avrxmega2:
1307 val = E_AVR_MACH_XMEGA2;
1308 break;
1309
1310 case bfd_mach_avrxmega3:
1311 val = E_AVR_MACH_XMEGA3;
1312 break;
1313
1314 case bfd_mach_avrxmega4:
1315 val = E_AVR_MACH_XMEGA4;
1316 break;
1317
1318 case bfd_mach_avrxmega5:
1319 val = E_AVR_MACH_XMEGA5;
1320 break;
1321
1322 case bfd_mach_avrxmega6:
1323 val = E_AVR_MACH_XMEGA6;
1324 break;
1325
1326 case bfd_mach_avrxmega7:
1327 val = E_AVR_MACH_XMEGA7;
1328 break;
1329 }
1330
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;
1335 }
1336
1337 /* Set the right machine number. */
1338
1339 static bfd_boolean
1340 elf32_avr_object_p (bfd *abfd)
1341 {
1342 unsigned int e_set = bfd_mach_avr2;
1343
1344 if (elf_elfheader (abfd)->e_machine == EM_AVR
1345 || elf_elfheader (abfd)->e_machine == EM_AVR_OLD)
1346 {
1347 int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
1348
1349 switch (e_mach)
1350 {
1351 default:
1352 case E_AVR_MACH_AVR2:
1353 e_set = bfd_mach_avr2;
1354 break;
1355
1356 case E_AVR_MACH_AVR1:
1357 e_set = bfd_mach_avr1;
1358 break;
1359
1360 case E_AVR_MACH_AVR25:
1361 e_set = bfd_mach_avr25;
1362 break;
1363
1364 case E_AVR_MACH_AVR3:
1365 e_set = bfd_mach_avr3;
1366 break;
1367
1368 case E_AVR_MACH_AVR31:
1369 e_set = bfd_mach_avr31;
1370 break;
1371
1372 case E_AVR_MACH_AVR35:
1373 e_set = bfd_mach_avr35;
1374 break;
1375
1376 case E_AVR_MACH_AVR4:
1377 e_set = bfd_mach_avr4;
1378 break;
1379
1380 case E_AVR_MACH_AVR5:
1381 e_set = bfd_mach_avr5;
1382 break;
1383
1384 case E_AVR_MACH_AVR51:
1385 e_set = bfd_mach_avr51;
1386 break;
1387
1388 case E_AVR_MACH_AVR6:
1389 e_set = bfd_mach_avr6;
1390 break;
1391
1392 case E_AVR_MACH_XMEGA1:
1393 e_set = bfd_mach_avrxmega1;
1394 break;
1395
1396 case E_AVR_MACH_XMEGA2:
1397 e_set = bfd_mach_avrxmega2;
1398 break;
1399
1400 case E_AVR_MACH_XMEGA3:
1401 e_set = bfd_mach_avrxmega3;
1402 break;
1403
1404 case E_AVR_MACH_XMEGA4:
1405 e_set = bfd_mach_avrxmega4;
1406 break;
1407
1408 case E_AVR_MACH_XMEGA5:
1409 e_set = bfd_mach_avrxmega5;
1410 break;
1411
1412 case E_AVR_MACH_XMEGA6:
1413 e_set = bfd_mach_avrxmega6;
1414 break;
1415
1416 case E_AVR_MACH_XMEGA7:
1417 e_set = bfd_mach_avrxmega7;
1418 break;
1419 }
1420 }
1421 return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
1422 e_set);
1423 }
1424
1425
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. */
1430
1431 static bfd_boolean
1432 elf32_avr_relax_delete_bytes (bfd *abfd,
1433 asection *sec,
1434 bfd_vma addr,
1435 int count)
1436 {
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;
1447
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;
1451
1452 toaddr = sec->size;
1453
1454 irel = elf_section_data (sec)->relocs;
1455 irelend = irel + sec->reloc_count;
1456
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;
1462
1463 /* Adjust all the reloc addresses. */
1464 for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
1465 {
1466 bfd_vma old_reloc_address;
1467
1468 old_reloc_address = (sec->output_section->vma
1469 + sec->output_offset + irel->r_offset);
1470
1471 /* Get the new reloc address. */
1472 if ((irel->r_offset > addr
1473 && irel->r_offset < toaddr))
1474 {
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));
1481
1482 irel->r_offset -= count;
1483 }
1484
1485 }
1486
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.
1492
1493 The most common case where this happens are relocs relative to
1494 the section-start symbol.
1495
1496 This step needs to be done for all of the sections of the bfd. */
1497
1498 {
1499 struct bfd_section *isec;
1500
1501 for (isec = abfd->sections; isec; isec = isec->next)
1502 {
1503 bfd_vma symval;
1504 bfd_vma shrinked_insn_address;
1505
1506 shrinked_insn_address = (sec->output_section->vma
1507 + sec->output_offset + addr - count);
1508
1509 irelend = elf_section_data (isec)->relocs + isec->reloc_count;
1510 for (irel = elf_section_data (isec)->relocs;
1511 irel < irelend;
1512 irel++)
1513 {
1514 /* Read this BFD's local symbols if we haven't done
1515 so already. */
1516 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1517 {
1518 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1519 if (isymbuf == NULL)
1520 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1521 symtab_hdr->sh_info, 0,
1522 NULL, NULL, NULL);
1523 if (isymbuf == NULL)
1524 return FALSE;
1525 }
1526
1527 /* Get the value of the symbol referred to by the reloc. */
1528 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1529 {
1530 /* A local symbol. */
1531 asection *sym_sec;
1532
1533 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1534 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1535 symval = isym->st_value;
1536 /* If the reloc is absolute, it will not have
1537 a symbol or section associated with it. */
1538 if (sym_sec == sec)
1539 {
1540 symval += sym_sec->output_section->vma
1541 + sym_sec->output_offset;
1542
1543 if (debug_relax)
1544 printf ("Checking if the relocation's "
1545 "addend needs corrections.\n"
1546 "Address of anchor symbol: 0x%x \n"
1547 "Address of relocation target: 0x%x \n"
1548 "Address of relaxed insn: 0x%x \n",
1549 (unsigned int) symval,
1550 (unsigned int) (symval + irel->r_addend),
1551 (unsigned int) shrinked_insn_address);
1552
1553 if (symval <= shrinked_insn_address
1554 && (symval + irel->r_addend) > shrinked_insn_address)
1555 {
1556 irel->r_addend -= count;
1557
1558 if (debug_relax)
1559 printf ("Relocation's addend needed to be fixed \n");
1560 }
1561 }
1562 /* else...Reference symbol is absolute. No adjustment needed. */
1563 }
1564 /* else...Reference symbol is extern. No need for adjusting
1565 the addend. */
1566 }
1567 }
1568 }
1569
1570 /* Adjust the local symbols defined in this section. */
1571 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
1572 /* Fix PR 9841, there may be no local symbols. */
1573 if (isym != NULL)
1574 {
1575 Elf_Internal_Sym *isymend;
1576
1577 isymend = isym + symtab_hdr->sh_info;
1578 for (; isym < isymend; isym++)
1579 {
1580 if (isym->st_shndx == sec_shndx
1581 && isym->st_value > addr
1582 && isym->st_value < toaddr)
1583 isym->st_value -= count;
1584 }
1585 }
1586
1587 /* Now adjust the global symbols defined in this section. */
1588 symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
1589 - symtab_hdr->sh_info);
1590 sym_hashes = elf_sym_hashes (abfd);
1591 end_hashes = sym_hashes + symcount;
1592 for (; sym_hashes < end_hashes; sym_hashes++)
1593 {
1594 struct elf_link_hash_entry *sym_hash = *sym_hashes;
1595 if ((sym_hash->root.type == bfd_link_hash_defined
1596 || sym_hash->root.type == bfd_link_hash_defweak)
1597 && sym_hash->root.u.def.section == sec
1598 && sym_hash->root.u.def.value > addr
1599 && sym_hash->root.u.def.value < toaddr)
1600 {
1601 sym_hash->root.u.def.value -= count;
1602 }
1603 }
1604
1605 return TRUE;
1606 }
1607
1608 /* This function handles relaxing for the avr.
1609 Many important relaxing opportunities within functions are already
1610 realized by the compiler itself.
1611 Here we try to replace call (4 bytes) -> rcall (2 bytes)
1612 and jump -> rjmp (safes also 2 bytes).
1613 As well we now optimize seqences of
1614 - call/rcall function
1615 - ret
1616 to yield
1617 - jmp/rjmp function
1618 - ret
1619 . In case that within a sequence
1620 - jmp/rjmp label
1621 - ret
1622 the ret could no longer be reached it is optimized away. In order
1623 to check if the ret is no longer needed, it is checked that the ret's address
1624 is not the target of a branch or jump within the same section, it is checked
1625 that there is no skip instruction before the jmp/rjmp and that there
1626 is no local or global label place at the address of the ret.
1627
1628 We refrain from relaxing within sections ".vectors" and
1629 ".jumptables" in order to maintain the position of the instructions.
1630 There, however, we substitute jmp/call by a sequence rjmp,nop/rcall,nop
1631 if possible. (In future one could possibly use the space of the nop
1632 for the first instruction of the irq service function.
1633
1634 The .jumptables sections is meant to be used for a future tablejump variant
1635 for the devices with 3-byte program counter where the table itself
1636 contains 4-byte jump instructions whose relative offset must not
1637 be changed. */
1638
1639 static bfd_boolean
1640 elf32_avr_relax_section (bfd *abfd,
1641 asection *sec,
1642 struct bfd_link_info *link_info,
1643 bfd_boolean *again)
1644 {
1645 Elf_Internal_Shdr *symtab_hdr;
1646 Elf_Internal_Rela *internal_relocs;
1647 Elf_Internal_Rela *irel, *irelend;
1648 bfd_byte *contents = NULL;
1649 Elf_Internal_Sym *isymbuf = NULL;
1650 struct elf32_avr_link_hash_table *htab;
1651
1652 if (link_info->relocatable)
1653 (*link_info->callbacks->einfo)
1654 (_("%P%F: --relax and -r may not be used together\n"));
1655
1656 htab = avr_link_hash_table (link_info);
1657 if (htab == NULL)
1658 return FALSE;
1659
1660 /* Assume nothing changes. */
1661 *again = FALSE;
1662
1663 if ((!htab->no_stubs) && (sec == htab->stub_sec))
1664 {
1665 /* We are just relaxing the stub section.
1666 Let's calculate the size needed again. */
1667 bfd_size_type last_estimated_stub_section_size = htab->stub_sec->size;
1668
1669 if (debug_relax)
1670 printf ("Relaxing the stub section. Size prior to this pass: %i\n",
1671 (int) last_estimated_stub_section_size);
1672
1673 elf32_avr_size_stubs (htab->stub_sec->output_section->owner,
1674 link_info, FALSE);
1675
1676 /* Check if the number of trampolines changed. */
1677 if (last_estimated_stub_section_size != htab->stub_sec->size)
1678 *again = TRUE;
1679
1680 if (debug_relax)
1681 printf ("Size of stub section after this pass: %i\n",
1682 (int) htab->stub_sec->size);
1683
1684 return TRUE;
1685 }
1686
1687 /* We don't have to do anything for a relocatable link, if
1688 this section does not have relocs, or if this is not a
1689 code section. */
1690 if (link_info->relocatable
1691 || (sec->flags & SEC_RELOC) == 0
1692 || sec->reloc_count == 0
1693 || (sec->flags & SEC_CODE) == 0)
1694 return TRUE;
1695
1696 /* Check if the object file to relax uses internal symbols so that we
1697 could fix up the relocations. */
1698 if (!(elf_elfheader (abfd)->e_flags & EF_AVR_LINKRELAX_PREPARED))
1699 return TRUE;
1700
1701 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1702
1703 /* Get a copy of the native relocations. */
1704 internal_relocs = (_bfd_elf_link_read_relocs
1705 (abfd, sec, NULL, NULL, link_info->keep_memory));
1706 if (internal_relocs == NULL)
1707 goto error_return;
1708
1709 /* Walk through the relocs looking for relaxing opportunities. */
1710 irelend = internal_relocs + sec->reloc_count;
1711 for (irel = internal_relocs; irel < irelend; irel++)
1712 {
1713 bfd_vma symval;
1714
1715 if ( ELF32_R_TYPE (irel->r_info) != R_AVR_13_PCREL
1716 && ELF32_R_TYPE (irel->r_info) != R_AVR_7_PCREL
1717 && ELF32_R_TYPE (irel->r_info) != R_AVR_CALL)
1718 continue;
1719
1720 /* Get the section contents if we haven't done so already. */
1721 if (contents == NULL)
1722 {
1723 /* Get cached copy if it exists. */
1724 if (elf_section_data (sec)->this_hdr.contents != NULL)
1725 contents = elf_section_data (sec)->this_hdr.contents;
1726 else
1727 {
1728 /* Go get them off disk. */
1729 if (! bfd_malloc_and_get_section (abfd, sec, &contents))
1730 goto error_return;
1731 }
1732 }
1733
1734 /* Read this BFD's local symbols if we haven't done so already. */
1735 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1736 {
1737 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1738 if (isymbuf == NULL)
1739 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1740 symtab_hdr->sh_info, 0,
1741 NULL, NULL, NULL);
1742 if (isymbuf == NULL)
1743 goto error_return;
1744 }
1745
1746
1747 /* Get the value of the symbol referred to by the reloc. */
1748 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1749 {
1750 /* A local symbol. */
1751 Elf_Internal_Sym *isym;
1752 asection *sym_sec;
1753
1754 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1755 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1756 symval = isym->st_value;
1757 /* If the reloc is absolute, it will not have
1758 a symbol or section associated with it. */
1759 if (sym_sec)
1760 symval += sym_sec->output_section->vma
1761 + sym_sec->output_offset;
1762 }
1763 else
1764 {
1765 unsigned long indx;
1766 struct elf_link_hash_entry *h;
1767
1768 /* An external symbol. */
1769 indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
1770 h = elf_sym_hashes (abfd)[indx];
1771 BFD_ASSERT (h != NULL);
1772 if (h->root.type != bfd_link_hash_defined
1773 && h->root.type != bfd_link_hash_defweak)
1774 /* This appears to be a reference to an undefined
1775 symbol. Just ignore it--it will be caught by the
1776 regular reloc processing. */
1777 continue;
1778
1779 symval = (h->root.u.def.value
1780 + h->root.u.def.section->output_section->vma
1781 + h->root.u.def.section->output_offset);
1782 }
1783
1784 /* For simplicity of coding, we are going to modify the section
1785 contents, the section relocs, and the BFD symbol table. We
1786 must tell the rest of the code not to free up this
1787 information. It would be possible to instead create a table
1788 of changes which have to be made, as is done in coff-mips.c;
1789 that would be more work, but would require less memory when
1790 the linker is run. */
1791 switch (ELF32_R_TYPE (irel->r_info))
1792 {
1793 /* Try to turn a 22-bit absolute call/jump into an 13-bit
1794 pc-relative rcall/rjmp. */
1795 case R_AVR_CALL:
1796 {
1797 bfd_vma value = symval + irel->r_addend;
1798 bfd_vma dot, gap;
1799 int distance_short_enough = 0;
1800
1801 /* Get the address of this instruction. */
1802 dot = (sec->output_section->vma
1803 + sec->output_offset + irel->r_offset);
1804
1805 /* Compute the distance from this insn to the branch target. */
1806 gap = value - dot;
1807
1808 /* If the distance is within -4094..+4098 inclusive, then we can
1809 relax this jump/call. +4098 because the call/jump target
1810 will be closer after the relaxation. */
1811 if ((int) gap >= -4094 && (int) gap <= 4098)
1812 distance_short_enough = 1;
1813
1814 /* Here we handle the wrap-around case. E.g. for a 16k device
1815 we could use a rjmp to jump from address 0x100 to 0x3d00!
1816 In order to make this work properly, we need to fill the
1817 vaiable avr_pc_wrap_around with the appropriate value.
1818 I.e. 0x4000 for a 16k device. */
1819 {
1820 /* Shrinking the code size makes the gaps larger in the
1821 case of wrap-arounds. So we use a heuristical safety
1822 margin to avoid that during relax the distance gets
1823 again too large for the short jumps. Let's assume
1824 a typical code-size reduction due to relax for a
1825 16k device of 600 bytes. So let's use twice the
1826 typical value as safety margin. */
1827 int rgap;
1828 int safety_margin;
1829
1830 int assumed_shrink = 600;
1831 if (avr_pc_wrap_around > 0x4000)
1832 assumed_shrink = 900;
1833
1834 safety_margin = 2 * assumed_shrink;
1835
1836 rgap = avr_relative_distance_considering_wrap_around (gap);
1837
1838 if (rgap >= (-4092 + safety_margin)
1839 && rgap <= (4094 - safety_margin))
1840 distance_short_enough = 1;
1841 }
1842
1843 if (distance_short_enough)
1844 {
1845 unsigned char code_msb;
1846 unsigned char code_lsb;
1847
1848 if (debug_relax)
1849 printf ("shrinking jump/call instruction at address 0x%x"
1850 " in section %s\n\n",
1851 (int) dot, sec->name);
1852
1853 /* Note that we've changed the relocs, section contents,
1854 etc. */
1855 elf_section_data (sec)->relocs = internal_relocs;
1856 elf_section_data (sec)->this_hdr.contents = contents;
1857 symtab_hdr->contents = (unsigned char *) isymbuf;
1858
1859 /* Get the instruction code for relaxing. */
1860 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset);
1861 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1862
1863 /* Mask out the relocation bits. */
1864 code_msb &= 0x94;
1865 code_lsb &= 0x0E;
1866 if (code_msb == 0x94 && code_lsb == 0x0E)
1867 {
1868 /* we are changing call -> rcall . */
1869 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1870 bfd_put_8 (abfd, 0xD0, contents + irel->r_offset + 1);
1871 }
1872 else if (code_msb == 0x94 && code_lsb == 0x0C)
1873 {
1874 /* we are changeing jump -> rjmp. */
1875 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1876 bfd_put_8 (abfd, 0xC0, contents + irel->r_offset + 1);
1877 }
1878 else
1879 abort ();
1880
1881 /* Fix the relocation's type. */
1882 irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
1883 R_AVR_13_PCREL);
1884
1885 /* Check for the vector section. There we don't want to
1886 modify the ordering! */
1887
1888 if (!strcmp (sec->name,".vectors")
1889 || !strcmp (sec->name,".jumptables"))
1890 {
1891 /* Let's insert a nop. */
1892 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
1893 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 3);
1894 }
1895 else
1896 {
1897 /* Delete two bytes of data. */
1898 if (!elf32_avr_relax_delete_bytes (abfd, sec,
1899 irel->r_offset + 2, 2))
1900 goto error_return;
1901
1902 /* That will change things, so, we should relax again.
1903 Note that this is not required, and it may be slow. */
1904 *again = TRUE;
1905 }
1906 }
1907 }
1908
1909 default:
1910 {
1911 unsigned char code_msb;
1912 unsigned char code_lsb;
1913 bfd_vma dot;
1914
1915 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1916 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset + 0);
1917
1918 /* Get the address of this instruction. */
1919 dot = (sec->output_section->vma
1920 + sec->output_offset + irel->r_offset);
1921
1922 /* Here we look for rcall/ret or call/ret sequences that could be
1923 safely replaced by rjmp/ret or jmp/ret. */
1924 if (((code_msb & 0xf0) == 0xd0)
1925 && avr_replace_call_ret_sequences)
1926 {
1927 /* This insn is a rcall. */
1928 unsigned char next_insn_msb = 0;
1929 unsigned char next_insn_lsb = 0;
1930
1931 if (irel->r_offset + 3 < sec->size)
1932 {
1933 next_insn_msb =
1934 bfd_get_8 (abfd, contents + irel->r_offset + 3);
1935 next_insn_lsb =
1936 bfd_get_8 (abfd, contents + irel->r_offset + 2);
1937 }
1938
1939 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1940 {
1941 /* The next insn is a ret. We now convert the rcall insn
1942 into a rjmp instruction. */
1943 code_msb &= 0xef;
1944 bfd_put_8 (abfd, code_msb, contents + irel->r_offset + 1);
1945 if (debug_relax)
1946 printf ("converted rcall/ret sequence at address 0x%x"
1947 " into rjmp/ret sequence. Section is %s\n\n",
1948 (int) dot, sec->name);
1949 *again = TRUE;
1950 break;
1951 }
1952 }
1953 else if ((0x94 == (code_msb & 0xfe))
1954 && (0x0e == (code_lsb & 0x0e))
1955 && avr_replace_call_ret_sequences)
1956 {
1957 /* This insn is a call. */
1958 unsigned char next_insn_msb = 0;
1959 unsigned char next_insn_lsb = 0;
1960
1961 if (irel->r_offset + 5 < sec->size)
1962 {
1963 next_insn_msb =
1964 bfd_get_8 (abfd, contents + irel->r_offset + 5);
1965 next_insn_lsb =
1966 bfd_get_8 (abfd, contents + irel->r_offset + 4);
1967 }
1968
1969 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1970 {
1971 /* The next insn is a ret. We now convert the call insn
1972 into a jmp instruction. */
1973
1974 code_lsb &= 0xfd;
1975 bfd_put_8 (abfd, code_lsb, contents + irel->r_offset);
1976 if (debug_relax)
1977 printf ("converted call/ret sequence at address 0x%x"
1978 " into jmp/ret sequence. Section is %s\n\n",
1979 (int) dot, sec->name);
1980 *again = TRUE;
1981 break;
1982 }
1983 }
1984 else if ((0xc0 == (code_msb & 0xf0))
1985 || ((0x94 == (code_msb & 0xfe))
1986 && (0x0c == (code_lsb & 0x0e))))
1987 {
1988 /* This insn is a rjmp or a jmp. */
1989 unsigned char next_insn_msb = 0;
1990 unsigned char next_insn_lsb = 0;
1991 int insn_size;
1992
1993 if (0xc0 == (code_msb & 0xf0))
1994 insn_size = 2; /* rjmp insn */
1995 else
1996 insn_size = 4; /* jmp insn */
1997
1998 if (irel->r_offset + insn_size + 1 < sec->size)
1999 {
2000 next_insn_msb =
2001 bfd_get_8 (abfd, contents + irel->r_offset
2002 + insn_size + 1);
2003 next_insn_lsb =
2004 bfd_get_8 (abfd, contents + irel->r_offset
2005 + insn_size);
2006 }
2007
2008 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
2009 {
2010 /* The next insn is a ret. We possibly could delete
2011 this ret. First we need to check for preceeding
2012 sbis/sbic/sbrs or cpse "skip" instructions. */
2013
2014 int there_is_preceeding_non_skip_insn = 1;
2015 bfd_vma address_of_ret;
2016
2017 address_of_ret = dot + insn_size;
2018
2019 if (debug_relax && (insn_size == 2))
2020 printf ("found rjmp / ret sequence at address 0x%x\n",
2021 (int) dot);
2022 if (debug_relax && (insn_size == 4))
2023 printf ("found jmp / ret sequence at address 0x%x\n",
2024 (int) dot);
2025
2026 /* We have to make sure that there is a preceeding insn. */
2027 if (irel->r_offset >= 2)
2028 {
2029 unsigned char preceeding_msb;
2030 unsigned char preceeding_lsb;
2031 preceeding_msb =
2032 bfd_get_8 (abfd, contents + irel->r_offset - 1);
2033 preceeding_lsb =
2034 bfd_get_8 (abfd, contents + irel->r_offset - 2);
2035
2036 /* sbic. */
2037 if (0x99 == preceeding_msb)
2038 there_is_preceeding_non_skip_insn = 0;
2039
2040 /* sbis. */
2041 if (0x9b == preceeding_msb)
2042 there_is_preceeding_non_skip_insn = 0;
2043
2044 /* sbrc */
2045 if ((0xfc == (preceeding_msb & 0xfe)
2046 && (0x00 == (preceeding_lsb & 0x08))))
2047 there_is_preceeding_non_skip_insn = 0;
2048
2049 /* sbrs */
2050 if ((0xfe == (preceeding_msb & 0xfe)
2051 && (0x00 == (preceeding_lsb & 0x08))))
2052 there_is_preceeding_non_skip_insn = 0;
2053
2054 /* cpse */
2055 if (0x10 == (preceeding_msb & 0xfc))
2056 there_is_preceeding_non_skip_insn = 0;
2057
2058 if (there_is_preceeding_non_skip_insn == 0)
2059 if (debug_relax)
2060 printf ("preceeding skip insn prevents deletion of"
2061 " ret insn at addr 0x%x in section %s\n",
2062 (int) dot + 2, sec->name);
2063 }
2064 else
2065 {
2066 /* There is no previous instruction. */
2067 there_is_preceeding_non_skip_insn = 0;
2068 }
2069
2070 if (there_is_preceeding_non_skip_insn)
2071 {
2072 /* We now only have to make sure that there is no
2073 local label defined at the address of the ret
2074 instruction and that there is no local relocation
2075 in this section pointing to the ret. */
2076
2077 int deleting_ret_is_safe = 1;
2078 unsigned int section_offset_of_ret_insn =
2079 irel->r_offset + insn_size;
2080 Elf_Internal_Sym *isym, *isymend;
2081 unsigned int sec_shndx;
2082
2083 sec_shndx =
2084 _bfd_elf_section_from_bfd_section (abfd, sec);
2085
2086 /* Check for local symbols. */
2087 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
2088 isymend = isym + symtab_hdr->sh_info;
2089 /* PR 6019: There may not be any local symbols. */
2090 for (; isym != NULL && isym < isymend; isym++)
2091 {
2092 if (isym->st_value == section_offset_of_ret_insn
2093 && isym->st_shndx == sec_shndx)
2094 {
2095 deleting_ret_is_safe = 0;
2096 if (debug_relax)
2097 printf ("local label prevents deletion of ret "
2098 "insn at address 0x%x\n",
2099 (int) dot + insn_size);
2100 }
2101 }
2102
2103 /* Now check for global symbols. */
2104 {
2105 int symcount;
2106 struct elf_link_hash_entry **sym_hashes;
2107 struct elf_link_hash_entry **end_hashes;
2108
2109 symcount = (symtab_hdr->sh_size
2110 / sizeof (Elf32_External_Sym)
2111 - symtab_hdr->sh_info);
2112 sym_hashes = elf_sym_hashes (abfd);
2113 end_hashes = sym_hashes + symcount;
2114 for (; sym_hashes < end_hashes; sym_hashes++)
2115 {
2116 struct elf_link_hash_entry *sym_hash =
2117 *sym_hashes;
2118 if ((sym_hash->root.type == bfd_link_hash_defined
2119 || sym_hash->root.type ==
2120 bfd_link_hash_defweak)
2121 && sym_hash->root.u.def.section == sec
2122 && sym_hash->root.u.def.value == section_offset_of_ret_insn)
2123 {
2124 deleting_ret_is_safe = 0;
2125 if (debug_relax)
2126 printf ("global label prevents deletion of "
2127 "ret insn at address 0x%x\n",
2128 (int) dot + insn_size);
2129 }
2130 }
2131 }
2132 /* Now we check for relocations pointing to ret. */
2133 {
2134 Elf_Internal_Rela *rel;
2135 Elf_Internal_Rela *relend;
2136
2137 relend = elf_section_data (sec)->relocs
2138 + sec->reloc_count;
2139
2140 for (rel = elf_section_data (sec)->relocs;
2141 rel < relend; rel++)
2142 {
2143 bfd_vma reloc_target = 0;
2144
2145 /* Read this BFD's local symbols if we haven't
2146 done so already. */
2147 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
2148 {
2149 isymbuf = (Elf_Internal_Sym *)
2150 symtab_hdr->contents;
2151 if (isymbuf == NULL)
2152 isymbuf = bfd_elf_get_elf_syms
2153 (abfd,
2154 symtab_hdr,
2155 symtab_hdr->sh_info, 0,
2156 NULL, NULL, NULL);
2157 if (isymbuf == NULL)
2158 break;
2159 }
2160
2161 /* Get the value of the symbol referred to
2162 by the reloc. */
2163 if (ELF32_R_SYM (rel->r_info)
2164 < symtab_hdr->sh_info)
2165 {
2166 /* A local symbol. */
2167 asection *sym_sec;
2168
2169 isym = isymbuf
2170 + ELF32_R_SYM (rel->r_info);
2171 sym_sec = bfd_section_from_elf_index
2172 (abfd, isym->st_shndx);
2173 symval = isym->st_value;
2174
2175 /* If the reloc is absolute, it will not
2176 have a symbol or section associated
2177 with it. */
2178
2179 if (sym_sec)
2180 {
2181 symval +=
2182 sym_sec->output_section->vma
2183 + sym_sec->output_offset;
2184 reloc_target = symval + rel->r_addend;
2185 }
2186 else
2187 {
2188 reloc_target = symval + rel->r_addend;
2189 /* Reference symbol is absolute. */
2190 }
2191 }
2192 /* else ... reference symbol is extern. */
2193
2194 if (address_of_ret == reloc_target)
2195 {
2196 deleting_ret_is_safe = 0;
2197 if (debug_relax)
2198 printf ("ret from "
2199 "rjmp/jmp ret sequence at address"
2200 " 0x%x could not be deleted. ret"
2201 " is target of a relocation.\n",
2202 (int) address_of_ret);
2203 }
2204 }
2205 }
2206
2207 if (deleting_ret_is_safe)
2208 {
2209 if (debug_relax)
2210 printf ("unreachable ret instruction "
2211 "at address 0x%x deleted.\n",
2212 (int) dot + insn_size);
2213
2214 /* Delete two bytes of data. */
2215 if (!elf32_avr_relax_delete_bytes (abfd, sec,
2216 irel->r_offset + insn_size, 2))
2217 goto error_return;
2218
2219 /* That will change things, so, we should relax
2220 again. Note that this is not required, and it
2221 may be slow. */
2222 *again = TRUE;
2223 break;
2224 }
2225 }
2226
2227 }
2228 }
2229 break;
2230 }
2231 }
2232 }
2233
2234 if (contents != NULL
2235 && elf_section_data (sec)->this_hdr.contents != contents)
2236 {
2237 if (! link_info->keep_memory)
2238 free (contents);
2239 else
2240 {
2241 /* Cache the section contents for elf_link_input_bfd. */
2242 elf_section_data (sec)->this_hdr.contents = contents;
2243 }
2244 }
2245
2246 if (internal_relocs != NULL
2247 && elf_section_data (sec)->relocs != internal_relocs)
2248 free (internal_relocs);
2249
2250 return TRUE;
2251
2252 error_return:
2253 if (isymbuf != NULL
2254 && symtab_hdr->contents != (unsigned char *) isymbuf)
2255 free (isymbuf);
2256 if (contents != NULL
2257 && elf_section_data (sec)->this_hdr.contents != contents)
2258 free (contents);
2259 if (internal_relocs != NULL
2260 && elf_section_data (sec)->relocs != internal_relocs)
2261 free (internal_relocs);
2262
2263 return FALSE;
2264 }
2265
2266 /* This is a version of bfd_generic_get_relocated_section_contents
2267 which uses elf32_avr_relocate_section.
2268
2269 For avr it's essentially a cut and paste taken from the H8300 port.
2270 The author of the relaxation support patch for avr had absolutely no
2271 clue what is happening here but found out that this part of the code
2272 seems to be important. */
2273
2274 static bfd_byte *
2275 elf32_avr_get_relocated_section_contents (bfd *output_bfd,
2276 struct bfd_link_info *link_info,
2277 struct bfd_link_order *link_order,
2278 bfd_byte *data,
2279 bfd_boolean relocatable,
2280 asymbol **symbols)
2281 {
2282 Elf_Internal_Shdr *symtab_hdr;
2283 asection *input_section = link_order->u.indirect.section;
2284 bfd *input_bfd = input_section->owner;
2285 asection **sections = NULL;
2286 Elf_Internal_Rela *internal_relocs = NULL;
2287 Elf_Internal_Sym *isymbuf = NULL;
2288
2289 /* We only need to handle the case of relaxing, or of having a
2290 particular set of section contents, specially. */
2291 if (relocatable
2292 || elf_section_data (input_section)->this_hdr.contents == NULL)
2293 return bfd_generic_get_relocated_section_contents (output_bfd, link_info,
2294 link_order, data,
2295 relocatable,
2296 symbols);
2297 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2298
2299 memcpy (data, elf_section_data (input_section)->this_hdr.contents,
2300 (size_t) input_section->size);
2301
2302 if ((input_section->flags & SEC_RELOC) != 0
2303 && input_section->reloc_count > 0)
2304 {
2305 asection **secpp;
2306 Elf_Internal_Sym *isym, *isymend;
2307 bfd_size_type amt;
2308
2309 internal_relocs = (_bfd_elf_link_read_relocs
2310 (input_bfd, input_section, NULL, NULL, FALSE));
2311 if (internal_relocs == NULL)
2312 goto error_return;
2313
2314 if (symtab_hdr->sh_info != 0)
2315 {
2316 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
2317 if (isymbuf == NULL)
2318 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2319 symtab_hdr->sh_info, 0,
2320 NULL, NULL, NULL);
2321 if (isymbuf == NULL)
2322 goto error_return;
2323 }
2324
2325 amt = symtab_hdr->sh_info;
2326 amt *= sizeof (asection *);
2327 sections = bfd_malloc (amt);
2328 if (sections == NULL && amt != 0)
2329 goto error_return;
2330
2331 isymend = isymbuf + symtab_hdr->sh_info;
2332 for (isym = isymbuf, secpp = sections; isym < isymend; ++isym, ++secpp)
2333 {
2334 asection *isec;
2335
2336 if (isym->st_shndx == SHN_UNDEF)
2337 isec = bfd_und_section_ptr;
2338 else if (isym->st_shndx == SHN_ABS)
2339 isec = bfd_abs_section_ptr;
2340 else if (isym->st_shndx == SHN_COMMON)
2341 isec = bfd_com_section_ptr;
2342 else
2343 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
2344
2345 *secpp = isec;
2346 }
2347
2348 if (! elf32_avr_relocate_section (output_bfd, link_info, input_bfd,
2349 input_section, data, internal_relocs,
2350 isymbuf, sections))
2351 goto error_return;
2352
2353 if (sections != NULL)
2354 free (sections);
2355 if (isymbuf != NULL
2356 && symtab_hdr->contents != (unsigned char *) isymbuf)
2357 free (isymbuf);
2358 if (elf_section_data (input_section)->relocs != internal_relocs)
2359 free (internal_relocs);
2360 }
2361
2362 return data;
2363
2364 error_return:
2365 if (sections != NULL)
2366 free (sections);
2367 if (isymbuf != NULL
2368 && symtab_hdr->contents != (unsigned char *) isymbuf)
2369 free (isymbuf);
2370 if (internal_relocs != NULL
2371 && elf_section_data (input_section)->relocs != internal_relocs)
2372 free (internal_relocs);
2373 return NULL;
2374 }
2375
2376
2377 /* Determines the hash entry name for a particular reloc. It consists of
2378 the identifier of the symbol section and the added reloc addend and
2379 symbol offset relative to the section the symbol is attached to. */
2380
2381 static char *
2382 avr_stub_name (const asection *symbol_section,
2383 const bfd_vma symbol_offset,
2384 const Elf_Internal_Rela *rela)
2385 {
2386 char *stub_name;
2387 bfd_size_type len;
2388
2389 len = 8 + 1 + 8 + 1 + 1;
2390 stub_name = bfd_malloc (len);
2391
2392 sprintf (stub_name, "%08x+%08x",
2393 symbol_section->id & 0xffffffff,
2394 (unsigned int) ((rela->r_addend & 0xffffffff) + symbol_offset));
2395
2396 return stub_name;
2397 }
2398
2399
2400 /* Add a new stub entry to the stub hash. Not all fields of the new
2401 stub entry are initialised. */
2402
2403 static struct elf32_avr_stub_hash_entry *
2404 avr_add_stub (const char *stub_name,
2405 struct elf32_avr_link_hash_table *htab)
2406 {
2407 struct elf32_avr_stub_hash_entry *hsh;
2408
2409 /* Enter this entry into the linker stub hash table. */
2410 hsh = avr_stub_hash_lookup (&htab->bstab, stub_name, TRUE, FALSE);
2411
2412 if (hsh == NULL)
2413 {
2414 (*_bfd_error_handler) (_("%B: cannot create stub entry %s"),
2415 NULL, stub_name);
2416 return NULL;
2417 }
2418
2419 hsh->stub_offset = 0;
2420 return hsh;
2421 }
2422
2423 /* We assume that there is already space allocated for the stub section
2424 contents and that before building the stubs the section size is
2425 initialized to 0. We assume that within the stub hash table entry,
2426 the absolute position of the jmp target has been written in the
2427 target_value field. We write here the offset of the generated jmp insn
2428 relative to the trampoline section start to the stub_offset entry in
2429 the stub hash table entry. */
2430
2431 static bfd_boolean
2432 avr_build_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2433 {
2434 struct elf32_avr_stub_hash_entry *hsh;
2435 struct bfd_link_info *info;
2436 struct elf32_avr_link_hash_table *htab;
2437 bfd *stub_bfd;
2438 bfd_byte *loc;
2439 bfd_vma target;
2440 bfd_vma starget;
2441
2442 /* Basic opcode */
2443 bfd_vma jmp_insn = 0x0000940c;
2444
2445 /* Massage our args to the form they really have. */
2446 hsh = avr_stub_hash_entry (bh);
2447
2448 if (!hsh->is_actually_needed)
2449 return TRUE;
2450
2451 info = (struct bfd_link_info *) in_arg;
2452
2453 htab = avr_link_hash_table (info);
2454 if (htab == NULL)
2455 return FALSE;
2456
2457 target = hsh->target_value;
2458
2459 /* Make a note of the offset within the stubs for this entry. */
2460 hsh->stub_offset = htab->stub_sec->size;
2461 loc = htab->stub_sec->contents + hsh->stub_offset;
2462
2463 stub_bfd = htab->stub_sec->owner;
2464
2465 if (debug_stubs)
2466 printf ("Building one Stub. Address: 0x%x, Offset: 0x%x\n",
2467 (unsigned int) target,
2468 (unsigned int) hsh->stub_offset);
2469
2470 /* We now have to add the information on the jump target to the bare
2471 opcode bits already set in jmp_insn. */
2472
2473 /* Check for the alignment of the address. */
2474 if (target & 1)
2475 return FALSE;
2476
2477 starget = target >> 1;
2478 jmp_insn |= ((starget & 0x10000) | ((starget << 3) & 0x1f00000)) >> 16;
2479 bfd_put_16 (stub_bfd, jmp_insn, loc);
2480 bfd_put_16 (stub_bfd, (bfd_vma) starget & 0xffff, loc + 2);
2481
2482 htab->stub_sec->size += 4;
2483
2484 /* Now add the entries in the address mapping table if there is still
2485 space left. */
2486 {
2487 unsigned int nr;
2488
2489 nr = htab->amt_entry_cnt + 1;
2490 if (nr <= htab->amt_max_entry_cnt)
2491 {
2492 htab->amt_entry_cnt = nr;
2493
2494 htab->amt_stub_offsets[nr - 1] = hsh->stub_offset;
2495 htab->amt_destination_addr[nr - 1] = target;
2496 }
2497 }
2498
2499 return TRUE;
2500 }
2501
2502 static bfd_boolean
2503 avr_mark_stub_not_to_be_necessary (struct bfd_hash_entry *bh,
2504 void *in_arg ATTRIBUTE_UNUSED)
2505 {
2506 struct elf32_avr_stub_hash_entry *hsh;
2507
2508 hsh = avr_stub_hash_entry (bh);
2509 hsh->is_actually_needed = FALSE;
2510
2511 return TRUE;
2512 }
2513
2514 static bfd_boolean
2515 avr_size_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2516 {
2517 struct elf32_avr_stub_hash_entry *hsh;
2518 struct elf32_avr_link_hash_table *htab;
2519 int size;
2520
2521 /* Massage our args to the form they really have. */
2522 hsh = avr_stub_hash_entry (bh);
2523 htab = in_arg;
2524
2525 if (hsh->is_actually_needed)
2526 size = 4;
2527 else
2528 size = 0;
2529
2530 htab->stub_sec->size += size;
2531 return TRUE;
2532 }
2533
2534 void
2535 elf32_avr_setup_params (struct bfd_link_info *info,
2536 bfd *avr_stub_bfd,
2537 asection *avr_stub_section,
2538 bfd_boolean no_stubs,
2539 bfd_boolean deb_stubs,
2540 bfd_boolean deb_relax,
2541 bfd_vma pc_wrap_around,
2542 bfd_boolean call_ret_replacement)
2543 {
2544 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2545
2546 if (htab == NULL)
2547 return;
2548 htab->stub_sec = avr_stub_section;
2549 htab->stub_bfd = avr_stub_bfd;
2550 htab->no_stubs = no_stubs;
2551
2552 debug_relax = deb_relax;
2553 debug_stubs = deb_stubs;
2554 avr_pc_wrap_around = pc_wrap_around;
2555 avr_replace_call_ret_sequences = call_ret_replacement;
2556 }
2557
2558
2559 /* Set up various things so that we can make a list of input sections
2560 for each output section included in the link. Returns -1 on error,
2561 0 when no stubs will be needed, and 1 on success. It also sets
2562 information on the stubs bfd and the stub section in the info
2563 struct. */
2564
2565 int
2566 elf32_avr_setup_section_lists (bfd *output_bfd,
2567 struct bfd_link_info *info)
2568 {
2569 bfd *input_bfd;
2570 unsigned int bfd_count;
2571 int top_id, top_index;
2572 asection *section;
2573 asection **input_list, **list;
2574 bfd_size_type amt;
2575 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2576
2577 if (htab == NULL || htab->no_stubs)
2578 return 0;
2579
2580 /* Count the number of input BFDs and find the top input section id. */
2581 for (input_bfd = info->input_bfds, bfd_count = 0, top_id = 0;
2582 input_bfd != NULL;
2583 input_bfd = input_bfd->link_next)
2584 {
2585 bfd_count += 1;
2586 for (section = input_bfd->sections;
2587 section != NULL;
2588 section = section->next)
2589 if (top_id < section->id)
2590 top_id = section->id;
2591 }
2592
2593 htab->bfd_count = bfd_count;
2594
2595 /* We can't use output_bfd->section_count here to find the top output
2596 section index as some sections may have been removed, and
2597 strip_excluded_output_sections doesn't renumber the indices. */
2598 for (section = output_bfd->sections, top_index = 0;
2599 section != NULL;
2600 section = section->next)
2601 if (top_index < section->index)
2602 top_index = section->index;
2603
2604 htab->top_index = top_index;
2605 amt = sizeof (asection *) * (top_index + 1);
2606 input_list = bfd_malloc (amt);
2607 htab->input_list = input_list;
2608 if (input_list == NULL)
2609 return -1;
2610
2611 /* For sections we aren't interested in, mark their entries with a
2612 value we can check later. */
2613 list = input_list + top_index;
2614 do
2615 *list = bfd_abs_section_ptr;
2616 while (list-- != input_list);
2617
2618 for (section = output_bfd->sections;
2619 section != NULL;
2620 section = section->next)
2621 if ((section->flags & SEC_CODE) != 0)
2622 input_list[section->index] = NULL;
2623
2624 return 1;
2625 }
2626
2627
2628 /* Read in all local syms for all input bfds, and create hash entries
2629 for export stubs if we are building a multi-subspace shared lib.
2630 Returns -1 on error, 0 otherwise. */
2631
2632 static int
2633 get_local_syms (bfd *input_bfd, struct bfd_link_info *info)
2634 {
2635 unsigned int bfd_indx;
2636 Elf_Internal_Sym *local_syms, **all_local_syms;
2637 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2638 bfd_size_type amt;
2639
2640 if (htab == NULL)
2641 return -1;
2642
2643 /* We want to read in symbol extension records only once. To do this
2644 we need to read in the local symbols in parallel and save them for
2645 later use; so hold pointers to the local symbols in an array. */
2646 amt = sizeof (Elf_Internal_Sym *) * htab->bfd_count;
2647 all_local_syms = bfd_zmalloc (amt);
2648 htab->all_local_syms = all_local_syms;
2649 if (all_local_syms == NULL)
2650 return -1;
2651
2652 /* Walk over all the input BFDs, swapping in local symbols.
2653 If we are creating a shared library, create hash entries for the
2654 export stubs. */
2655 for (bfd_indx = 0;
2656 input_bfd != NULL;
2657 input_bfd = input_bfd->link_next, bfd_indx++)
2658 {
2659 Elf_Internal_Shdr *symtab_hdr;
2660
2661 /* We'll need the symbol table in a second. */
2662 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2663 if (symtab_hdr->sh_info == 0)
2664 continue;
2665
2666 /* We need an array of the local symbols attached to the input bfd. */
2667 local_syms = (Elf_Internal_Sym *) symtab_hdr->contents;
2668 if (local_syms == NULL)
2669 {
2670 local_syms = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2671 symtab_hdr->sh_info, 0,
2672 NULL, NULL, NULL);
2673 /* Cache them for elf_link_input_bfd. */
2674 symtab_hdr->contents = (unsigned char *) local_syms;
2675 }
2676 if (local_syms == NULL)
2677 return -1;
2678
2679 all_local_syms[bfd_indx] = local_syms;
2680 }
2681
2682 return 0;
2683 }
2684
2685 #define ADD_DUMMY_STUBS_FOR_DEBUGGING 0
2686
2687 bfd_boolean
2688 elf32_avr_size_stubs (bfd *output_bfd,
2689 struct bfd_link_info *info,
2690 bfd_boolean is_prealloc_run)
2691 {
2692 struct elf32_avr_link_hash_table *htab;
2693 int stub_changed = 0;
2694
2695 htab = avr_link_hash_table (info);
2696 if (htab == NULL)
2697 return FALSE;
2698
2699 /* At this point we initialize htab->vector_base
2700 To the start of the text output section. */
2701 htab->vector_base = htab->stub_sec->output_section->vma;
2702
2703 if (get_local_syms (info->input_bfds, info))
2704 {
2705 if (htab->all_local_syms)
2706 goto error_ret_free_local;
2707 return FALSE;
2708 }
2709
2710 if (ADD_DUMMY_STUBS_FOR_DEBUGGING)
2711 {
2712 struct elf32_avr_stub_hash_entry *test;
2713
2714 test = avr_add_stub ("Hugo",htab);
2715 test->target_value = 0x123456;
2716 test->stub_offset = 13;
2717
2718 test = avr_add_stub ("Hugo2",htab);
2719 test->target_value = 0x84210;
2720 test->stub_offset = 14;
2721 }
2722
2723 while (1)
2724 {
2725 bfd *input_bfd;
2726 unsigned int bfd_indx;
2727
2728 /* We will have to re-generate the stub hash table each time anything
2729 in memory has changed. */
2730
2731 bfd_hash_traverse (&htab->bstab, avr_mark_stub_not_to_be_necessary, htab);
2732 for (input_bfd = info->input_bfds, bfd_indx = 0;
2733 input_bfd != NULL;
2734 input_bfd = input_bfd->link_next, bfd_indx++)
2735 {
2736 Elf_Internal_Shdr *symtab_hdr;
2737 asection *section;
2738 Elf_Internal_Sym *local_syms;
2739
2740 /* We'll need the symbol table in a second. */
2741 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2742 if (symtab_hdr->sh_info == 0)
2743 continue;
2744
2745 local_syms = htab->all_local_syms[bfd_indx];
2746
2747 /* Walk over each section attached to the input bfd. */
2748 for (section = input_bfd->sections;
2749 section != NULL;
2750 section = section->next)
2751 {
2752 Elf_Internal_Rela *internal_relocs, *irelaend, *irela;
2753
2754 /* If there aren't any relocs, then there's nothing more
2755 to do. */
2756 if ((section->flags & SEC_RELOC) == 0
2757 || section->reloc_count == 0)
2758 continue;
2759
2760 /* If this section is a link-once section that will be
2761 discarded, then don't create any stubs. */
2762 if (section->output_section == NULL
2763 || section->output_section->owner != output_bfd)
2764 continue;
2765
2766 /* Get the relocs. */
2767 internal_relocs
2768 = _bfd_elf_link_read_relocs (input_bfd, section, NULL, NULL,
2769 info->keep_memory);
2770 if (internal_relocs == NULL)
2771 goto error_ret_free_local;
2772
2773 /* Now examine each relocation. */
2774 irela = internal_relocs;
2775 irelaend = irela + section->reloc_count;
2776 for (; irela < irelaend; irela++)
2777 {
2778 unsigned int r_type, r_indx;
2779 struct elf32_avr_stub_hash_entry *hsh;
2780 asection *sym_sec;
2781 bfd_vma sym_value;
2782 bfd_vma destination;
2783 struct elf_link_hash_entry *hh;
2784 char *stub_name;
2785
2786 r_type = ELF32_R_TYPE (irela->r_info);
2787 r_indx = ELF32_R_SYM (irela->r_info);
2788
2789 /* Only look for 16 bit GS relocs. No other reloc will need a
2790 stub. */
2791 if (!((r_type == R_AVR_16_PM)
2792 || (r_type == R_AVR_LO8_LDI_GS)
2793 || (r_type == R_AVR_HI8_LDI_GS)))
2794 continue;
2795
2796 /* Now determine the call target, its name, value,
2797 section. */
2798 sym_sec = NULL;
2799 sym_value = 0;
2800 destination = 0;
2801 hh = NULL;
2802 if (r_indx < symtab_hdr->sh_info)
2803 {
2804 /* It's a local symbol. */
2805 Elf_Internal_Sym *sym;
2806 Elf_Internal_Shdr *hdr;
2807 unsigned int shndx;
2808
2809 sym = local_syms + r_indx;
2810 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2811 sym_value = sym->st_value;
2812 shndx = sym->st_shndx;
2813 if (shndx < elf_numsections (input_bfd))
2814 {
2815 hdr = elf_elfsections (input_bfd)[shndx];
2816 sym_sec = hdr->bfd_section;
2817 destination = (sym_value + irela->r_addend
2818 + sym_sec->output_offset
2819 + sym_sec->output_section->vma);
2820 }
2821 }
2822 else
2823 {
2824 /* It's an external symbol. */
2825 int e_indx;
2826
2827 e_indx = r_indx - symtab_hdr->sh_info;
2828 hh = elf_sym_hashes (input_bfd)[e_indx];
2829
2830 while (hh->root.type == bfd_link_hash_indirect
2831 || hh->root.type == bfd_link_hash_warning)
2832 hh = (struct elf_link_hash_entry *)
2833 (hh->root.u.i.link);
2834
2835 if (hh->root.type == bfd_link_hash_defined
2836 || hh->root.type == bfd_link_hash_defweak)
2837 {
2838 sym_sec = hh->root.u.def.section;
2839 sym_value = hh->root.u.def.value;
2840 if (sym_sec->output_section != NULL)
2841 destination = (sym_value + irela->r_addend
2842 + sym_sec->output_offset
2843 + sym_sec->output_section->vma);
2844 }
2845 else if (hh->root.type == bfd_link_hash_undefweak)
2846 {
2847 if (! info->shared)
2848 continue;
2849 }
2850 else if (hh->root.type == bfd_link_hash_undefined)
2851 {
2852 if (! (info->unresolved_syms_in_objects == RM_IGNORE
2853 && (ELF_ST_VISIBILITY (hh->other)
2854 == STV_DEFAULT)))
2855 continue;
2856 }
2857 else
2858 {
2859 bfd_set_error (bfd_error_bad_value);
2860
2861 error_ret_free_internal:
2862 if (elf_section_data (section)->relocs == NULL)
2863 free (internal_relocs);
2864 goto error_ret_free_local;
2865 }
2866 }
2867
2868 if (! avr_stub_is_required_for_16_bit_reloc
2869 (destination - htab->vector_base))
2870 {
2871 if (!is_prealloc_run)
2872 /* We are having a reloc that does't need a stub. */
2873 continue;
2874
2875 /* We don't right now know if a stub will be needed.
2876 Let's rather be on the safe side. */
2877 }
2878
2879 /* Get the name of this stub. */
2880 stub_name = avr_stub_name (sym_sec, sym_value, irela);
2881
2882 if (!stub_name)
2883 goto error_ret_free_internal;
2884
2885
2886 hsh = avr_stub_hash_lookup (&htab->bstab,
2887 stub_name,
2888 FALSE, FALSE);
2889 if (hsh != NULL)
2890 {
2891 /* The proper stub has already been created. Mark it
2892 to be used and write the possibly changed destination
2893 value. */
2894 hsh->is_actually_needed = TRUE;
2895 hsh->target_value = destination;
2896 free (stub_name);
2897 continue;
2898 }
2899
2900 hsh = avr_add_stub (stub_name, htab);
2901 if (hsh == NULL)
2902 {
2903 free (stub_name);
2904 goto error_ret_free_internal;
2905 }
2906
2907 hsh->is_actually_needed = TRUE;
2908 hsh->target_value = destination;
2909
2910 if (debug_stubs)
2911 printf ("Adding stub with destination 0x%x to the"
2912 " hash table.\n", (unsigned int) destination);
2913 if (debug_stubs)
2914 printf ("(Pre-Alloc run: %i)\n", is_prealloc_run);
2915
2916 stub_changed = TRUE;
2917 }
2918
2919 /* We're done with the internal relocs, free them. */
2920 if (elf_section_data (section)->relocs == NULL)
2921 free (internal_relocs);
2922 }
2923 }
2924
2925 /* Re-Calculate the number of needed stubs. */
2926 htab->stub_sec->size = 0;
2927 bfd_hash_traverse (&htab->bstab, avr_size_one_stub, htab);
2928
2929 if (!stub_changed)
2930 break;
2931
2932 stub_changed = FALSE;
2933 }
2934
2935 free (htab->all_local_syms);
2936 return TRUE;
2937
2938 error_ret_free_local:
2939 free (htab->all_local_syms);
2940 return FALSE;
2941 }
2942
2943
2944 /* Build all the stubs associated with the current output file. The
2945 stubs are kept in a hash table attached to the main linker hash
2946 table. We also set up the .plt entries for statically linked PIC
2947 functions here. This function is called via hppaelf_finish in the
2948 linker. */
2949
2950 bfd_boolean
2951 elf32_avr_build_stubs (struct bfd_link_info *info)
2952 {
2953 asection *stub_sec;
2954 struct bfd_hash_table *table;
2955 struct elf32_avr_link_hash_table *htab;
2956 bfd_size_type total_size = 0;
2957
2958 htab = avr_link_hash_table (info);
2959 if (htab == NULL)
2960 return FALSE;
2961
2962 /* In case that there were several stub sections: */
2963 for (stub_sec = htab->stub_bfd->sections;
2964 stub_sec != NULL;
2965 stub_sec = stub_sec->next)
2966 {
2967 bfd_size_type size;
2968
2969 /* Allocate memory to hold the linker stubs. */
2970 size = stub_sec->size;
2971 total_size += size;
2972
2973 stub_sec->contents = bfd_zalloc (htab->stub_bfd, size);
2974 if (stub_sec->contents == NULL && size != 0)
2975 return FALSE;
2976 stub_sec->size = 0;
2977 }
2978
2979 /* Allocate memory for the adress mapping table. */
2980 htab->amt_entry_cnt = 0;
2981 htab->amt_max_entry_cnt = total_size / 4;
2982 htab->amt_stub_offsets = bfd_malloc (sizeof (bfd_vma)
2983 * htab->amt_max_entry_cnt);
2984 htab->amt_destination_addr = bfd_malloc (sizeof (bfd_vma)
2985 * htab->amt_max_entry_cnt );
2986
2987 if (debug_stubs)
2988 printf ("Allocating %i entries in the AMT\n", htab->amt_max_entry_cnt);
2989
2990 /* Build the stubs as directed by the stub hash table. */
2991 table = &htab->bstab;
2992 bfd_hash_traverse (table, avr_build_one_stub, info);
2993
2994 if (debug_stubs)
2995 printf ("Final Stub section Size: %i\n", (int) htab->stub_sec->size);
2996
2997 return TRUE;
2998 }
2999
3000 #define ELF_ARCH bfd_arch_avr
3001 #define ELF_TARGET_ID AVR_ELF_DATA
3002 #define ELF_MACHINE_CODE EM_AVR
3003 #define ELF_MACHINE_ALT1 EM_AVR_OLD
3004 #define ELF_MAXPAGESIZE 1
3005
3006 #define TARGET_LITTLE_SYM bfd_elf32_avr_vec
3007 #define TARGET_LITTLE_NAME "elf32-avr"
3008
3009 #define bfd_elf32_bfd_link_hash_table_create elf32_avr_link_hash_table_create
3010 #define bfd_elf32_bfd_link_hash_table_free elf32_avr_link_hash_table_free
3011
3012 #define elf_info_to_howto avr_info_to_howto_rela
3013 #define elf_info_to_howto_rel NULL
3014 #define elf_backend_relocate_section elf32_avr_relocate_section
3015 #define elf_backend_can_gc_sections 1
3016 #define elf_backend_rela_normal 1
3017 #define elf_backend_final_write_processing \
3018 bfd_elf_avr_final_write_processing
3019 #define elf_backend_object_p elf32_avr_object_p
3020
3021 #define bfd_elf32_bfd_relax_section elf32_avr_relax_section
3022 #define bfd_elf32_bfd_get_relocated_section_contents \
3023 elf32_avr_get_relocated_section_contents
3024
3025 #include "elf32-target.h"
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