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[deliverable/binutils-gdb.git] / bfd / elf32-avr.c
1 /* AVR-specific support for 32-bit ELF
2 Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008
3 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_tablse 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 ((p)->hash->table.newfunc != elf32_avr_link_hash_newfunc ? NULL : \
108 ((struct elf32_avr_link_hash_table *) ((p)->hash)))
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 };
506
507 /* Map BFD reloc types to AVR ELF reloc types. */
508
509 struct avr_reloc_map
510 {
511 bfd_reloc_code_real_type bfd_reloc_val;
512 unsigned int elf_reloc_val;
513 };
514
515 static const struct avr_reloc_map avr_reloc_map[] =
516 {
517 { BFD_RELOC_NONE, R_AVR_NONE },
518 { BFD_RELOC_32, R_AVR_32 },
519 { BFD_RELOC_AVR_7_PCREL, R_AVR_7_PCREL },
520 { BFD_RELOC_AVR_13_PCREL, R_AVR_13_PCREL },
521 { BFD_RELOC_16, R_AVR_16 },
522 { BFD_RELOC_AVR_16_PM, R_AVR_16_PM },
523 { BFD_RELOC_AVR_LO8_LDI, R_AVR_LO8_LDI},
524 { BFD_RELOC_AVR_HI8_LDI, R_AVR_HI8_LDI },
525 { BFD_RELOC_AVR_HH8_LDI, R_AVR_HH8_LDI },
526 { BFD_RELOC_AVR_MS8_LDI, R_AVR_MS8_LDI },
527 { BFD_RELOC_AVR_LO8_LDI_NEG, R_AVR_LO8_LDI_NEG },
528 { BFD_RELOC_AVR_HI8_LDI_NEG, R_AVR_HI8_LDI_NEG },
529 { BFD_RELOC_AVR_HH8_LDI_NEG, R_AVR_HH8_LDI_NEG },
530 { BFD_RELOC_AVR_MS8_LDI_NEG, R_AVR_MS8_LDI_NEG },
531 { BFD_RELOC_AVR_LO8_LDI_PM, R_AVR_LO8_LDI_PM },
532 { BFD_RELOC_AVR_LO8_LDI_GS, R_AVR_LO8_LDI_GS },
533 { BFD_RELOC_AVR_HI8_LDI_PM, R_AVR_HI8_LDI_PM },
534 { BFD_RELOC_AVR_HI8_LDI_GS, R_AVR_HI8_LDI_GS },
535 { BFD_RELOC_AVR_HH8_LDI_PM, R_AVR_HH8_LDI_PM },
536 { BFD_RELOC_AVR_LO8_LDI_PM_NEG, R_AVR_LO8_LDI_PM_NEG },
537 { BFD_RELOC_AVR_HI8_LDI_PM_NEG, R_AVR_HI8_LDI_PM_NEG },
538 { BFD_RELOC_AVR_HH8_LDI_PM_NEG, R_AVR_HH8_LDI_PM_NEG },
539 { BFD_RELOC_AVR_CALL, R_AVR_CALL },
540 { BFD_RELOC_AVR_LDI, R_AVR_LDI },
541 { BFD_RELOC_AVR_6, R_AVR_6 },
542 { BFD_RELOC_AVR_6_ADIW, R_AVR_6_ADIW }
543 };
544
545 /* Meant to be filled one day with the wrap around address for the
546 specific device. I.e. should get the value 0x4000 for 16k devices,
547 0x8000 for 32k devices and so on.
548
549 We initialize it here with a value of 0x1000000 resulting in
550 that we will never suggest a wrap-around jump during relaxation.
551 The logic of the source code later on assumes that in
552 avr_pc_wrap_around one single bit is set. */
553 static bfd_vma avr_pc_wrap_around = 0x10000000;
554
555 /* If this variable holds a value different from zero, the linker relaxation
556 machine will try to optimize call/ret sequences by a single jump
557 instruction. This option could be switched off by a linker switch. */
558 static int avr_replace_call_ret_sequences = 1;
559 \f
560 /* Initialize an entry in the stub hash table. */
561
562 static struct bfd_hash_entry *
563 stub_hash_newfunc (struct bfd_hash_entry *entry,
564 struct bfd_hash_table *table,
565 const char *string)
566 {
567 /* Allocate the structure if it has not already been allocated by a
568 subclass. */
569 if (entry == NULL)
570 {
571 entry = bfd_hash_allocate (table,
572 sizeof (struct elf32_avr_stub_hash_entry));
573 if (entry == NULL)
574 return entry;
575 }
576
577 /* Call the allocation method of the superclass. */
578 entry = bfd_hash_newfunc (entry, table, string);
579 if (entry != NULL)
580 {
581 struct elf32_avr_stub_hash_entry *hsh;
582
583 /* Initialize the local fields. */
584 hsh = avr_stub_hash_entry (entry);
585 hsh->stub_offset = 0;
586 hsh->target_value = 0;
587 }
588
589 return entry;
590 }
591
592 /* This function is just a straight passthrough to the real
593 function in linker.c. Its prupose is so that its address
594 can be compared inside the avr_link_hash_table macro. */
595
596 static struct bfd_hash_entry *
597 elf32_avr_link_hash_newfunc (struct bfd_hash_entry * entry,
598 struct bfd_hash_table * table,
599 const char * string)
600 {
601 return _bfd_elf_link_hash_newfunc (entry, table, string);
602 }
603
604 /* Create the derived linker hash table. The AVR ELF port uses the derived
605 hash table to keep information specific to the AVR ELF linker (without
606 using static variables). */
607
608 static struct bfd_link_hash_table *
609 elf32_avr_link_hash_table_create (bfd *abfd)
610 {
611 struct elf32_avr_link_hash_table *htab;
612 bfd_size_type amt = sizeof (*htab);
613
614 htab = bfd_malloc (amt);
615 if (htab == NULL)
616 return NULL;
617
618 if (!_bfd_elf_link_hash_table_init (&htab->etab, abfd,
619 elf32_avr_link_hash_newfunc,
620 sizeof (struct elf_link_hash_entry)))
621 {
622 free (htab);
623 return NULL;
624 }
625
626 /* Init the stub hash table too. */
627 if (!bfd_hash_table_init (&htab->bstab, stub_hash_newfunc,
628 sizeof (struct elf32_avr_stub_hash_entry)))
629 return NULL;
630
631 htab->stub_bfd = NULL;
632 htab->stub_sec = NULL;
633
634 /* Initialize the address mapping table. */
635 htab->amt_stub_offsets = NULL;
636 htab->amt_destination_addr = NULL;
637 htab->amt_entry_cnt = 0;
638 htab->amt_max_entry_cnt = 0;
639
640 return &htab->etab.root;
641 }
642
643 /* Free the derived linker hash table. */
644
645 static void
646 elf32_avr_link_hash_table_free (struct bfd_link_hash_table *btab)
647 {
648 struct elf32_avr_link_hash_table *htab
649 = (struct elf32_avr_link_hash_table *) btab;
650
651 /* Free the address mapping table. */
652 if (htab->amt_stub_offsets != NULL)
653 free (htab->amt_stub_offsets);
654 if (htab->amt_destination_addr != NULL)
655 free (htab->amt_destination_addr);
656
657 bfd_hash_table_free (&htab->bstab);
658 _bfd_generic_link_hash_table_free (btab);
659 }
660
661 /* Calculates the effective distance of a pc relative jump/call. */
662
663 static int
664 avr_relative_distance_considering_wrap_around (unsigned int distance)
665 {
666 unsigned int wrap_around_mask = avr_pc_wrap_around - 1;
667 int dist_with_wrap_around = distance & wrap_around_mask;
668
669 if (dist_with_wrap_around > ((int) (avr_pc_wrap_around >> 1)))
670 dist_with_wrap_around -= avr_pc_wrap_around;
671
672 return dist_with_wrap_around;
673 }
674
675
676 static reloc_howto_type *
677 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
678 bfd_reloc_code_real_type code)
679 {
680 unsigned int i;
681
682 for (i = 0;
683 i < sizeof (avr_reloc_map) / sizeof (struct avr_reloc_map);
684 i++)
685 if (avr_reloc_map[i].bfd_reloc_val == code)
686 return &elf_avr_howto_table[avr_reloc_map[i].elf_reloc_val];
687
688 return NULL;
689 }
690
691 static reloc_howto_type *
692 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
693 const char *r_name)
694 {
695 unsigned int i;
696
697 for (i = 0;
698 i < sizeof (elf_avr_howto_table) / sizeof (elf_avr_howto_table[0]);
699 i++)
700 if (elf_avr_howto_table[i].name != NULL
701 && strcasecmp (elf_avr_howto_table[i].name, r_name) == 0)
702 return &elf_avr_howto_table[i];
703
704 return NULL;
705 }
706
707 /* Set the howto pointer for an AVR ELF reloc. */
708
709 static void
710 avr_info_to_howto_rela (bfd *abfd ATTRIBUTE_UNUSED,
711 arelent *cache_ptr,
712 Elf_Internal_Rela *dst)
713 {
714 unsigned int r_type;
715
716 r_type = ELF32_R_TYPE (dst->r_info);
717 BFD_ASSERT (r_type < (unsigned int) R_AVR_max);
718 cache_ptr->howto = &elf_avr_howto_table[r_type];
719 }
720
721 /* Look through the relocs for a section during the first phase.
722 Since we don't do .gots or .plts, we just need to consider the
723 virtual table relocs for gc. */
724
725 static bfd_boolean
726 elf32_avr_check_relocs (bfd *abfd,
727 struct bfd_link_info *info,
728 asection *sec,
729 const Elf_Internal_Rela *relocs)
730 {
731 Elf_Internal_Shdr *symtab_hdr;
732 struct elf_link_hash_entry **sym_hashes;
733 const Elf_Internal_Rela *rel;
734 const Elf_Internal_Rela *rel_end;
735
736 if (info->relocatable)
737 return TRUE;
738
739 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
740 sym_hashes = elf_sym_hashes (abfd);
741
742 rel_end = relocs + sec->reloc_count;
743 for (rel = relocs; rel < rel_end; rel++)
744 {
745 struct elf_link_hash_entry *h;
746 unsigned long r_symndx;
747
748 r_symndx = ELF32_R_SYM (rel->r_info);
749 if (r_symndx < symtab_hdr->sh_info)
750 h = NULL;
751 else
752 {
753 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
754 while (h->root.type == bfd_link_hash_indirect
755 || h->root.type == bfd_link_hash_warning)
756 h = (struct elf_link_hash_entry *) h->root.u.i.link;
757 }
758 }
759
760 return TRUE;
761 }
762
763 static bfd_boolean
764 avr_stub_is_required_for_16_bit_reloc (bfd_vma relocation)
765 {
766 return (relocation >= 0x020000);
767 }
768
769 /* Returns the address of the corresponding stub if there is one.
770 Returns otherwise an address above 0x020000. This function
771 could also be used, if there is no knowledge on the section where
772 the destination is found. */
773
774 static bfd_vma
775 avr_get_stub_addr (bfd_vma srel,
776 struct elf32_avr_link_hash_table *htab)
777 {
778 unsigned int index;
779 bfd_vma stub_sec_addr =
780 (htab->stub_sec->output_section->vma +
781 htab->stub_sec->output_offset);
782
783 for (index = 0; index < htab->amt_max_entry_cnt; index ++)
784 if (htab->amt_destination_addr[index] == srel)
785 return htab->amt_stub_offsets[index] + stub_sec_addr;
786
787 /* Return an address that could not be reached by 16 bit relocs. */
788 return 0x020000;
789 }
790
791 /* Perform a single relocation. By default we use the standard BFD
792 routines, but a few relocs, we have to do them ourselves. */
793
794 static bfd_reloc_status_type
795 avr_final_link_relocate (reloc_howto_type * howto,
796 bfd * input_bfd,
797 asection * input_section,
798 bfd_byte * contents,
799 Elf_Internal_Rela * rel,
800 bfd_vma relocation,
801 struct elf32_avr_link_hash_table * htab)
802 {
803 bfd_reloc_status_type r = bfd_reloc_ok;
804 bfd_vma x;
805 bfd_signed_vma srel;
806 bfd_signed_vma reloc_addr;
807 bfd_boolean use_stubs = FALSE;
808 /* Usually is 0, unless we are generating code for a bootloader. */
809 bfd_signed_vma base_addr = htab->vector_base;
810
811 /* Absolute addr of the reloc in the final excecutable. */
812 reloc_addr = rel->r_offset + input_section->output_section->vma
813 + input_section->output_offset;
814
815 switch (howto->type)
816 {
817 case R_AVR_7_PCREL:
818 contents += rel->r_offset;
819 srel = (bfd_signed_vma) relocation;
820 srel += rel->r_addend;
821 srel -= rel->r_offset;
822 srel -= 2; /* Branch instructions add 2 to the PC... */
823 srel -= (input_section->output_section->vma +
824 input_section->output_offset);
825
826 if (srel & 1)
827 return bfd_reloc_outofrange;
828 if (srel > ((1 << 7) - 1) || (srel < - (1 << 7)))
829 return bfd_reloc_overflow;
830 x = bfd_get_16 (input_bfd, contents);
831 x = (x & 0xfc07) | (((srel >> 1) << 3) & 0x3f8);
832 bfd_put_16 (input_bfd, x, contents);
833 break;
834
835 case R_AVR_13_PCREL:
836 contents += rel->r_offset;
837 srel = (bfd_signed_vma) relocation;
838 srel += rel->r_addend;
839 srel -= rel->r_offset;
840 srel -= 2; /* Branch instructions add 2 to the PC... */
841 srel -= (input_section->output_section->vma +
842 input_section->output_offset);
843
844 if (srel & 1)
845 return bfd_reloc_outofrange;
846
847 srel = avr_relative_distance_considering_wrap_around (srel);
848
849 /* AVR addresses commands as words. */
850 srel >>= 1;
851
852 /* Check for overflow. */
853 if (srel < -2048 || srel > 2047)
854 {
855 /* Relative distance is too large. */
856
857 /* Always apply WRAPAROUND for avr2 and avr4. */
858 switch (bfd_get_mach (input_bfd))
859 {
860 case bfd_mach_avr2:
861 case bfd_mach_avr4:
862 break;
863
864 default:
865 return bfd_reloc_overflow;
866 }
867 }
868
869 x = bfd_get_16 (input_bfd, contents);
870 x = (x & 0xf000) | (srel & 0xfff);
871 bfd_put_16 (input_bfd, x, contents);
872 break;
873
874 case R_AVR_LO8_LDI:
875 contents += rel->r_offset;
876 srel = (bfd_signed_vma) relocation + rel->r_addend;
877 x = bfd_get_16 (input_bfd, contents);
878 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
879 bfd_put_16 (input_bfd, x, contents);
880 break;
881
882 case R_AVR_LDI:
883 contents += rel->r_offset;
884 srel = (bfd_signed_vma) relocation + rel->r_addend;
885 if (((srel > 0) && (srel & 0xffff) > 255)
886 || ((srel < 0) && ((-srel) & 0xffff) > 128))
887 /* Remove offset for data/eeprom section. */
888 return bfd_reloc_overflow;
889
890 x = bfd_get_16 (input_bfd, contents);
891 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
892 bfd_put_16 (input_bfd, x, contents);
893 break;
894
895 case R_AVR_6:
896 contents += rel->r_offset;
897 srel = (bfd_signed_vma) relocation + rel->r_addend;
898 if (((srel & 0xffff) > 63) || (srel < 0))
899 /* Remove offset for data/eeprom section. */
900 return bfd_reloc_overflow;
901 x = bfd_get_16 (input_bfd, contents);
902 x = (x & 0xd3f8) | ((srel & 7) | ((srel & (3 << 3)) << 7)
903 | ((srel & (1 << 5)) << 8));
904 bfd_put_16 (input_bfd, x, contents);
905 break;
906
907 case R_AVR_6_ADIW:
908 contents += rel->r_offset;
909 srel = (bfd_signed_vma) relocation + rel->r_addend;
910 if (((srel & 0xffff) > 63) || (srel < 0))
911 /* Remove offset for data/eeprom section. */
912 return bfd_reloc_overflow;
913 x = bfd_get_16 (input_bfd, contents);
914 x = (x & 0xff30) | (srel & 0xf) | ((srel & 0x30) << 2);
915 bfd_put_16 (input_bfd, x, contents);
916 break;
917
918 case R_AVR_HI8_LDI:
919 contents += rel->r_offset;
920 srel = (bfd_signed_vma) relocation + rel->r_addend;
921 srel = (srel >> 8) & 0xff;
922 x = bfd_get_16 (input_bfd, contents);
923 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
924 bfd_put_16 (input_bfd, x, contents);
925 break;
926
927 case R_AVR_HH8_LDI:
928 contents += rel->r_offset;
929 srel = (bfd_signed_vma) relocation + rel->r_addend;
930 srel = (srel >> 16) & 0xff;
931 x = bfd_get_16 (input_bfd, contents);
932 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
933 bfd_put_16 (input_bfd, x, contents);
934 break;
935
936 case R_AVR_MS8_LDI:
937 contents += rel->r_offset;
938 srel = (bfd_signed_vma) relocation + rel->r_addend;
939 srel = (srel >> 24) & 0xff;
940 x = bfd_get_16 (input_bfd, contents);
941 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
942 bfd_put_16 (input_bfd, x, contents);
943 break;
944
945 case R_AVR_LO8_LDI_NEG:
946 contents += rel->r_offset;
947 srel = (bfd_signed_vma) relocation + rel->r_addend;
948 srel = -srel;
949 x = bfd_get_16 (input_bfd, contents);
950 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
951 bfd_put_16 (input_bfd, x, contents);
952 break;
953
954 case R_AVR_HI8_LDI_NEG:
955 contents += rel->r_offset;
956 srel = (bfd_signed_vma) relocation + rel->r_addend;
957 srel = -srel;
958 srel = (srel >> 8) & 0xff;
959 x = bfd_get_16 (input_bfd, contents);
960 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
961 bfd_put_16 (input_bfd, x, contents);
962 break;
963
964 case R_AVR_HH8_LDI_NEG:
965 contents += rel->r_offset;
966 srel = (bfd_signed_vma) relocation + rel->r_addend;
967 srel = -srel;
968 srel = (srel >> 16) & 0xff;
969 x = bfd_get_16 (input_bfd, contents);
970 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
971 bfd_put_16 (input_bfd, x, contents);
972 break;
973
974 case R_AVR_MS8_LDI_NEG:
975 contents += rel->r_offset;
976 srel = (bfd_signed_vma) relocation + rel->r_addend;
977 srel = -srel;
978 srel = (srel >> 24) & 0xff;
979 x = bfd_get_16 (input_bfd, contents);
980 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
981 bfd_put_16 (input_bfd, x, contents);
982 break;
983
984 case R_AVR_LO8_LDI_GS:
985 use_stubs = (!htab->no_stubs);
986 /* Fall through. */
987 case R_AVR_LO8_LDI_PM:
988 contents += rel->r_offset;
989 srel = (bfd_signed_vma) relocation + rel->r_addend;
990
991 if (use_stubs
992 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
993 {
994 bfd_vma old_srel = srel;
995
996 /* We need to use the address of the stub instead. */
997 srel = avr_get_stub_addr (srel, htab);
998 if (debug_stubs)
999 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
1000 "reloc at address 0x%x.\n",
1001 (unsigned int) srel,
1002 (unsigned int) old_srel,
1003 (unsigned int) reloc_addr);
1004
1005 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1006 return bfd_reloc_outofrange;
1007 }
1008
1009 if (srel & 1)
1010 return bfd_reloc_outofrange;
1011 srel = srel >> 1;
1012 x = bfd_get_16 (input_bfd, contents);
1013 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1014 bfd_put_16 (input_bfd, x, contents);
1015 break;
1016
1017 case R_AVR_HI8_LDI_GS:
1018 use_stubs = (!htab->no_stubs);
1019 /* Fall through. */
1020 case R_AVR_HI8_LDI_PM:
1021 contents += rel->r_offset;
1022 srel = (bfd_signed_vma) relocation + rel->r_addend;
1023
1024 if (use_stubs
1025 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1026 {
1027 bfd_vma old_srel = srel;
1028
1029 /* We need to use the address of the stub instead. */
1030 srel = avr_get_stub_addr (srel, htab);
1031 if (debug_stubs)
1032 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
1033 "reloc at address 0x%x.\n",
1034 (unsigned int) srel,
1035 (unsigned int) old_srel,
1036 (unsigned int) reloc_addr);
1037
1038 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1039 return bfd_reloc_outofrange;
1040 }
1041
1042 if (srel & 1)
1043 return bfd_reloc_outofrange;
1044 srel = srel >> 1;
1045 srel = (srel >> 8) & 0xff;
1046 x = bfd_get_16 (input_bfd, contents);
1047 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1048 bfd_put_16 (input_bfd, x, contents);
1049 break;
1050
1051 case R_AVR_HH8_LDI_PM:
1052 contents += rel->r_offset;
1053 srel = (bfd_signed_vma) relocation + rel->r_addend;
1054 if (srel & 1)
1055 return bfd_reloc_outofrange;
1056 srel = srel >> 1;
1057 srel = (srel >> 16) & 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_LO8_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 x = bfd_get_16 (input_bfd, contents);
1071 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1072 bfd_put_16 (input_bfd, x, contents);
1073 break;
1074
1075 case R_AVR_HI8_LDI_PM_NEG:
1076 contents += rel->r_offset;
1077 srel = (bfd_signed_vma) relocation + rel->r_addend;
1078 srel = -srel;
1079 if (srel & 1)
1080 return bfd_reloc_outofrange;
1081 srel = srel >> 1;
1082 srel = (srel >> 8) & 0xff;
1083 x = bfd_get_16 (input_bfd, contents);
1084 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1085 bfd_put_16 (input_bfd, x, contents);
1086 break;
1087
1088 case R_AVR_HH8_LDI_PM_NEG:
1089 contents += rel->r_offset;
1090 srel = (bfd_signed_vma) relocation + rel->r_addend;
1091 srel = -srel;
1092 if (srel & 1)
1093 return bfd_reloc_outofrange;
1094 srel = srel >> 1;
1095 srel = (srel >> 16) & 0xff;
1096 x = bfd_get_16 (input_bfd, contents);
1097 x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
1098 bfd_put_16 (input_bfd, x, contents);
1099 break;
1100
1101 case R_AVR_CALL:
1102 contents += rel->r_offset;
1103 srel = (bfd_signed_vma) relocation + rel->r_addend;
1104 if (srel & 1)
1105 return bfd_reloc_outofrange;
1106 srel = srel >> 1;
1107 x = bfd_get_16 (input_bfd, contents);
1108 x |= ((srel & 0x10000) | ((srel << 3) & 0x1f00000)) >> 16;
1109 bfd_put_16 (input_bfd, x, contents);
1110 bfd_put_16 (input_bfd, (bfd_vma) srel & 0xffff, contents+2);
1111 break;
1112
1113 case R_AVR_16_PM:
1114 use_stubs = (!htab->no_stubs);
1115 contents += rel->r_offset;
1116 srel = (bfd_signed_vma) relocation + rel->r_addend;
1117
1118 if (use_stubs
1119 && avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1120 {
1121 bfd_vma old_srel = srel;
1122
1123 /* We need to use the address of the stub instead. */
1124 srel = avr_get_stub_addr (srel,htab);
1125 if (debug_stubs)
1126 printf ("LD: Using jump stub (at 0x%x) with destination 0x%x for "
1127 "reloc at address 0x%x.\n",
1128 (unsigned int) srel,
1129 (unsigned int) old_srel,
1130 (unsigned int) reloc_addr);
1131
1132 if (avr_stub_is_required_for_16_bit_reloc (srel - base_addr))
1133 return bfd_reloc_outofrange;
1134 }
1135
1136 if (srel & 1)
1137 return bfd_reloc_outofrange;
1138 srel = srel >> 1;
1139 bfd_put_16 (input_bfd, (bfd_vma) srel &0x00ffff, contents);
1140 break;
1141
1142 default:
1143 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1144 contents, rel->r_offset,
1145 relocation, rel->r_addend);
1146 }
1147
1148 return r;
1149 }
1150
1151 /* Relocate an AVR ELF section. */
1152
1153 static bfd_boolean
1154 elf32_avr_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
1155 struct bfd_link_info *info,
1156 bfd *input_bfd,
1157 asection *input_section,
1158 bfd_byte *contents,
1159 Elf_Internal_Rela *relocs,
1160 Elf_Internal_Sym *local_syms,
1161 asection **local_sections)
1162 {
1163 Elf_Internal_Shdr * symtab_hdr;
1164 struct elf_link_hash_entry ** sym_hashes;
1165 Elf_Internal_Rela * rel;
1166 Elf_Internal_Rela * relend;
1167 struct elf32_avr_link_hash_table * htab = avr_link_hash_table (info);
1168
1169 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
1170 sym_hashes = elf_sym_hashes (input_bfd);
1171 relend = relocs + input_section->reloc_count;
1172
1173 for (rel = relocs; rel < relend; rel ++)
1174 {
1175 reloc_howto_type * howto;
1176 unsigned long r_symndx;
1177 Elf_Internal_Sym * sym;
1178 asection * sec;
1179 struct elf_link_hash_entry * h;
1180 bfd_vma relocation;
1181 bfd_reloc_status_type r;
1182 const char * name;
1183 int r_type;
1184
1185 r_type = ELF32_R_TYPE (rel->r_info);
1186 r_symndx = ELF32_R_SYM (rel->r_info);
1187 howto = elf_avr_howto_table + ELF32_R_TYPE (rel->r_info);
1188 h = NULL;
1189 sym = NULL;
1190 sec = NULL;
1191
1192 if (r_symndx < symtab_hdr->sh_info)
1193 {
1194 sym = local_syms + r_symndx;
1195 sec = local_sections [r_symndx];
1196 relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);
1197
1198 name = bfd_elf_string_from_elf_section
1199 (input_bfd, symtab_hdr->sh_link, sym->st_name);
1200 name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
1201 }
1202 else
1203 {
1204 bfd_boolean unresolved_reloc, warned;
1205
1206 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
1207 r_symndx, symtab_hdr, sym_hashes,
1208 h, sec, relocation,
1209 unresolved_reloc, warned);
1210
1211 name = h->root.root.string;
1212 }
1213
1214 if (sec != NULL && elf_discarded_section (sec))
1215 {
1216 /* For relocs against symbols from removed linkonce sections,
1217 or sections discarded by a linker script, we just want the
1218 section contents zeroed. Avoid any special processing. */
1219 _bfd_clear_contents (howto, input_bfd, contents + rel->r_offset);
1220 rel->r_info = 0;
1221 rel->r_addend = 0;
1222 continue;
1223 }
1224
1225 if (info->relocatable)
1226 continue;
1227
1228 r = avr_final_link_relocate (howto, input_bfd, input_section,
1229 contents, rel, relocation, htab);
1230
1231 if (r != bfd_reloc_ok)
1232 {
1233 const char * msg = (const char *) NULL;
1234
1235 switch (r)
1236 {
1237 case bfd_reloc_overflow:
1238 r = info->callbacks->reloc_overflow
1239 (info, (h ? &h->root : NULL),
1240 name, howto->name, (bfd_vma) 0,
1241 input_bfd, input_section, rel->r_offset);
1242 break;
1243
1244 case bfd_reloc_undefined:
1245 r = info->callbacks->undefined_symbol
1246 (info, name, input_bfd, input_section, rel->r_offset, TRUE);
1247 break;
1248
1249 case bfd_reloc_outofrange:
1250 msg = _("internal error: out of range error");
1251 break;
1252
1253 case bfd_reloc_notsupported:
1254 msg = _("internal error: unsupported relocation error");
1255 break;
1256
1257 case bfd_reloc_dangerous:
1258 msg = _("internal error: dangerous relocation");
1259 break;
1260
1261 default:
1262 msg = _("internal error: unknown error");
1263 break;
1264 }
1265
1266 if (msg)
1267 r = info->callbacks->warning
1268 (info, msg, name, input_bfd, input_section, rel->r_offset);
1269
1270 if (! r)
1271 return FALSE;
1272 }
1273 }
1274
1275 return TRUE;
1276 }
1277
1278 /* The final processing done just before writing out a AVR ELF object
1279 file. This gets the AVR architecture right based on the machine
1280 number. */
1281
1282 static void
1283 bfd_elf_avr_final_write_processing (bfd *abfd,
1284 bfd_boolean linker ATTRIBUTE_UNUSED)
1285 {
1286 unsigned long val;
1287
1288 switch (bfd_get_mach (abfd))
1289 {
1290 default:
1291 case bfd_mach_avr2:
1292 val = E_AVR_MACH_AVR2;
1293 break;
1294
1295 case bfd_mach_avr1:
1296 val = E_AVR_MACH_AVR1;
1297 break;
1298
1299 case bfd_mach_avr3:
1300 val = E_AVR_MACH_AVR3;
1301 break;
1302
1303 case bfd_mach_avr4:
1304 val = E_AVR_MACH_AVR4;
1305 break;
1306
1307 case bfd_mach_avr5:
1308 val = E_AVR_MACH_AVR5;
1309 break;
1310
1311 case bfd_mach_avr6:
1312 val = E_AVR_MACH_AVR6;
1313 break;
1314 }
1315
1316 elf_elfheader (abfd)->e_machine = EM_AVR;
1317 elf_elfheader (abfd)->e_flags &= ~ EF_AVR_MACH;
1318 elf_elfheader (abfd)->e_flags |= val;
1319 elf_elfheader (abfd)->e_flags |= EF_AVR_LINKRELAX_PREPARED;
1320 }
1321
1322 /* Set the right machine number. */
1323
1324 static bfd_boolean
1325 elf32_avr_object_p (bfd *abfd)
1326 {
1327 unsigned int e_set = bfd_mach_avr2;
1328
1329 if (elf_elfheader (abfd)->e_machine == EM_AVR
1330 || elf_elfheader (abfd)->e_machine == EM_AVR_OLD)
1331 {
1332 int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
1333
1334 switch (e_mach)
1335 {
1336 default:
1337 case E_AVR_MACH_AVR2:
1338 e_set = bfd_mach_avr2;
1339 break;
1340
1341 case E_AVR_MACH_AVR1:
1342 e_set = bfd_mach_avr1;
1343 break;
1344
1345 case E_AVR_MACH_AVR3:
1346 e_set = bfd_mach_avr3;
1347 break;
1348
1349 case E_AVR_MACH_AVR4:
1350 e_set = bfd_mach_avr4;
1351 break;
1352
1353 case E_AVR_MACH_AVR5:
1354 e_set = bfd_mach_avr5;
1355 break;
1356
1357 case E_AVR_MACH_AVR6:
1358 e_set = bfd_mach_avr6;
1359 break;
1360 }
1361 }
1362 return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
1363 e_set);
1364 }
1365
1366
1367 /* Delete some bytes from a section while changing the size of an instruction.
1368 The parameter "addr" denotes the section-relative offset pointing just
1369 behind the shrinked instruction. "addr+count" point at the first
1370 byte just behind the original unshrinked instruction. */
1371
1372 static bfd_boolean
1373 elf32_avr_relax_delete_bytes (bfd *abfd,
1374 asection *sec,
1375 bfd_vma addr,
1376 int count)
1377 {
1378 Elf_Internal_Shdr *symtab_hdr;
1379 unsigned int sec_shndx;
1380 bfd_byte *contents;
1381 Elf_Internal_Rela *irel, *irelend;
1382 Elf_Internal_Rela *irelalign;
1383 Elf_Internal_Sym *isym;
1384 Elf_Internal_Sym *isymbuf = NULL;
1385 Elf_Internal_Sym *isymend;
1386 bfd_vma toaddr;
1387 struct elf_link_hash_entry **sym_hashes;
1388 struct elf_link_hash_entry **end_hashes;
1389 unsigned int symcount;
1390
1391 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1392 sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
1393 contents = elf_section_data (sec)->this_hdr.contents;
1394
1395 /* The deletion must stop at the next ALIGN reloc for an aligment
1396 power larger than the number of bytes we are deleting. */
1397
1398 irelalign = NULL;
1399 toaddr = sec->size;
1400
1401 irel = elf_section_data (sec)->relocs;
1402 irelend = irel + sec->reloc_count;
1403
1404 /* Actually delete the bytes. */
1405 if (toaddr - addr - count > 0)
1406 memmove (contents + addr, contents + addr + count,
1407 (size_t) (toaddr - addr - count));
1408 sec->size -= count;
1409
1410 /* Adjust all the reloc addresses. */
1411 for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
1412 {
1413 bfd_vma old_reloc_address;
1414 bfd_vma shrinked_insn_address;
1415
1416 old_reloc_address = (sec->output_section->vma
1417 + sec->output_offset + irel->r_offset);
1418 shrinked_insn_address = (sec->output_section->vma
1419 + sec->output_offset + addr - count);
1420
1421 /* Get the new reloc address. */
1422 if ((irel->r_offset > addr
1423 && irel->r_offset < toaddr))
1424 {
1425 if (debug_relax)
1426 printf ("Relocation at address 0x%x needs to be moved.\n"
1427 "Old section offset: 0x%x, New section offset: 0x%x \n",
1428 (unsigned int) old_reloc_address,
1429 (unsigned int) irel->r_offset,
1430 (unsigned int) ((irel->r_offset) - count));
1431
1432 irel->r_offset -= count;
1433 }
1434
1435 }
1436
1437 /* The reloc's own addresses are now ok. However, we need to readjust
1438 the reloc's addend, i.e. the reloc's value if two conditions are met:
1439 1.) the reloc is relative to a symbol in this section that
1440 is located in front of the shrinked instruction
1441 2.) symbol plus addend end up behind the shrinked instruction.
1442
1443 The most common case where this happens are relocs relative to
1444 the section-start symbol.
1445
1446 This step needs to be done for all of the sections of the bfd. */
1447
1448 {
1449 struct bfd_section *isec;
1450
1451 for (isec = abfd->sections; isec; isec = isec->next)
1452 {
1453 bfd_vma symval;
1454 bfd_vma shrinked_insn_address;
1455
1456 shrinked_insn_address = (sec->output_section->vma
1457 + sec->output_offset + addr - count);
1458
1459 irelend = elf_section_data (isec)->relocs + isec->reloc_count;
1460 for (irel = elf_section_data (isec)->relocs;
1461 irel < irelend;
1462 irel++)
1463 {
1464 /* Read this BFD's local symbols if we haven't done
1465 so already. */
1466 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1467 {
1468 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1469 if (isymbuf == NULL)
1470 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1471 symtab_hdr->sh_info, 0,
1472 NULL, NULL, NULL);
1473 if (isymbuf == NULL)
1474 return FALSE;
1475 }
1476
1477 /* Get the value of the symbol referred to by the reloc. */
1478 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1479 {
1480 /* A local symbol. */
1481 Elf_Internal_Sym *isym;
1482 asection *sym_sec;
1483
1484 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1485 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1486 symval = isym->st_value;
1487 /* If the reloc is absolute, it will not have
1488 a symbol or section associated with it. */
1489 if (sym_sec == sec)
1490 {
1491 symval += sym_sec->output_section->vma
1492 + sym_sec->output_offset;
1493
1494 if (debug_relax)
1495 printf ("Checking if the relocation's "
1496 "addend needs corrections.\n"
1497 "Address of anchor symbol: 0x%x \n"
1498 "Address of relocation target: 0x%x \n"
1499 "Address of relaxed insn: 0x%x \n",
1500 (unsigned int) symval,
1501 (unsigned int) (symval + irel->r_addend),
1502 (unsigned int) shrinked_insn_address);
1503
1504 if (symval <= shrinked_insn_address
1505 && (symval + irel->r_addend) > shrinked_insn_address)
1506 {
1507 irel->r_addend -= count;
1508
1509 if (debug_relax)
1510 printf ("Relocation's addend needed to be fixed \n");
1511 }
1512 }
1513 /* else...Reference symbol is absolute. No adjustment needed. */
1514 }
1515 /* else...Reference symbol is extern. No need for adjusting
1516 the addend. */
1517 }
1518 }
1519 }
1520
1521 /* Adjust the local symbols defined in this section. */
1522 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
1523 isymend = isym + symtab_hdr->sh_info;
1524 for (; isym < isymend; isym++)
1525 {
1526 if (isym->st_shndx == sec_shndx
1527 && isym->st_value > addr
1528 && isym->st_value < toaddr)
1529 isym->st_value -= count;
1530 }
1531
1532 /* Now adjust the global symbols defined in this section. */
1533 symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
1534 - symtab_hdr->sh_info);
1535 sym_hashes = elf_sym_hashes (abfd);
1536 end_hashes = sym_hashes + symcount;
1537 for (; sym_hashes < end_hashes; sym_hashes++)
1538 {
1539 struct elf_link_hash_entry *sym_hash = *sym_hashes;
1540 if ((sym_hash->root.type == bfd_link_hash_defined
1541 || sym_hash->root.type == bfd_link_hash_defweak)
1542 && sym_hash->root.u.def.section == sec
1543 && sym_hash->root.u.def.value > addr
1544 && sym_hash->root.u.def.value < toaddr)
1545 {
1546 sym_hash->root.u.def.value -= count;
1547 }
1548 }
1549
1550 return TRUE;
1551 }
1552
1553 /* This function handles relaxing for the avr.
1554 Many important relaxing opportunities within functions are already
1555 realized by the compiler itself.
1556 Here we try to replace call (4 bytes) -> rcall (2 bytes)
1557 and jump -> rjmp (safes also 2 bytes).
1558 As well we now optimize seqences of
1559 - call/rcall function
1560 - ret
1561 to yield
1562 - jmp/rjmp function
1563 - ret
1564 . In case that within a sequence
1565 - jmp/rjmp label
1566 - ret
1567 the ret could no longer be reached it is optimized away. In order
1568 to check if the ret is no longer needed, it is checked that the ret's address
1569 is not the target of a branch or jump within the same section, it is checked
1570 that there is no skip instruction before the jmp/rjmp and that there
1571 is no local or global label place at the address of the ret.
1572
1573 We refrain from relaxing within sections ".vectors" and
1574 ".jumptables" in order to maintain the position of the instructions.
1575 There, however, we substitute jmp/call by a sequence rjmp,nop/rcall,nop
1576 if possible. (In future one could possibly use the space of the nop
1577 for the first instruction of the irq service function.
1578
1579 The .jumptables sections is meant to be used for a future tablejump variant
1580 for the devices with 3-byte program counter where the table itself
1581 contains 4-byte jump instructions whose relative offset must not
1582 be changed. */
1583
1584 static bfd_boolean
1585 elf32_avr_relax_section (bfd *abfd,
1586 asection *sec,
1587 struct bfd_link_info *link_info,
1588 bfd_boolean *again)
1589 {
1590 Elf_Internal_Shdr *symtab_hdr;
1591 Elf_Internal_Rela *internal_relocs;
1592 Elf_Internal_Rela *irel, *irelend;
1593 bfd_byte *contents = NULL;
1594 Elf_Internal_Sym *isymbuf = NULL;
1595 static asection *last_input_section = NULL;
1596 static Elf_Internal_Rela *last_reloc = NULL;
1597 struct elf32_avr_link_hash_table *htab;
1598
1599 htab = avr_link_hash_table (link_info);
1600 if (htab == NULL)
1601 return FALSE;
1602
1603 /* Assume nothing changes. */
1604 *again = FALSE;
1605
1606 if ((!htab->no_stubs) && (sec == htab->stub_sec))
1607 {
1608 /* We are just relaxing the stub section.
1609 Let's calculate the size needed again. */
1610 bfd_size_type last_estimated_stub_section_size = htab->stub_sec->size;
1611
1612 if (debug_relax)
1613 printf ("Relaxing the stub section. Size prior to this pass: %i\n",
1614 (int) last_estimated_stub_section_size);
1615
1616 elf32_avr_size_stubs (htab->stub_sec->output_section->owner,
1617 link_info, FALSE);
1618
1619 /* Check if the number of trampolines changed. */
1620 if (last_estimated_stub_section_size != htab->stub_sec->size)
1621 *again = TRUE;
1622
1623 if (debug_relax)
1624 printf ("Size of stub section after this pass: %i\n",
1625 (int) htab->stub_sec->size);
1626
1627 return TRUE;
1628 }
1629
1630 /* We don't have to do anything for a relocatable link, if
1631 this section does not have relocs, or if this is not a
1632 code section. */
1633 if (link_info->relocatable
1634 || (sec->flags & SEC_RELOC) == 0
1635 || sec->reloc_count == 0
1636 || (sec->flags & SEC_CODE) == 0)
1637 return TRUE;
1638
1639 /* Check if the object file to relax uses internal symbols so that we
1640 could fix up the relocations. */
1641 if (!(elf_elfheader (abfd)->e_flags & EF_AVR_LINKRELAX_PREPARED))
1642 return TRUE;
1643
1644 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1645
1646 /* Get a copy of the native relocations. */
1647 internal_relocs = (_bfd_elf_link_read_relocs
1648 (abfd, sec, NULL, NULL, link_info->keep_memory));
1649 if (internal_relocs == NULL)
1650 goto error_return;
1651
1652 if (sec != last_input_section)
1653 last_reloc = NULL;
1654
1655 last_input_section = sec;
1656
1657 /* Walk through the relocs looking for relaxing opportunities. */
1658 irelend = internal_relocs + sec->reloc_count;
1659 for (irel = internal_relocs; irel < irelend; irel++)
1660 {
1661 bfd_vma symval;
1662
1663 if ( ELF32_R_TYPE (irel->r_info) != R_AVR_13_PCREL
1664 && ELF32_R_TYPE (irel->r_info) != R_AVR_7_PCREL
1665 && ELF32_R_TYPE (irel->r_info) != R_AVR_CALL)
1666 continue;
1667
1668 /* Get the section contents if we haven't done so already. */
1669 if (contents == NULL)
1670 {
1671 /* Get cached copy if it exists. */
1672 if (elf_section_data (sec)->this_hdr.contents != NULL)
1673 contents = elf_section_data (sec)->this_hdr.contents;
1674 else
1675 {
1676 /* Go get them off disk. */
1677 if (! bfd_malloc_and_get_section (abfd, sec, &contents))
1678 goto error_return;
1679 }
1680 }
1681
1682 /* Read this BFD's local symbols if we haven't done so already. */
1683 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1684 {
1685 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1686 if (isymbuf == NULL)
1687 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1688 symtab_hdr->sh_info, 0,
1689 NULL, NULL, NULL);
1690 if (isymbuf == NULL)
1691 goto error_return;
1692 }
1693
1694
1695 /* Get the value of the symbol referred to by the reloc. */
1696 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1697 {
1698 /* A local symbol. */
1699 Elf_Internal_Sym *isym;
1700 asection *sym_sec;
1701
1702 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1703 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1704 symval = isym->st_value;
1705 /* If the reloc is absolute, it will not have
1706 a symbol or section associated with it. */
1707 if (sym_sec)
1708 symval += sym_sec->output_section->vma
1709 + sym_sec->output_offset;
1710 }
1711 else
1712 {
1713 unsigned long indx;
1714 struct elf_link_hash_entry *h;
1715
1716 /* An external symbol. */
1717 indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
1718 h = elf_sym_hashes (abfd)[indx];
1719 BFD_ASSERT (h != NULL);
1720 if (h->root.type != bfd_link_hash_defined
1721 && h->root.type != bfd_link_hash_defweak)
1722 /* This appears to be a reference to an undefined
1723 symbol. Just ignore it--it will be caught by the
1724 regular reloc processing. */
1725 continue;
1726
1727 symval = (h->root.u.def.value
1728 + h->root.u.def.section->output_section->vma
1729 + h->root.u.def.section->output_offset);
1730 }
1731
1732 /* For simplicity of coding, we are going to modify the section
1733 contents, the section relocs, and the BFD symbol table. We
1734 must tell the rest of the code not to free up this
1735 information. It would be possible to instead create a table
1736 of changes which have to be made, as is done in coff-mips.c;
1737 that would be more work, but would require less memory when
1738 the linker is run. */
1739 switch (ELF32_R_TYPE (irel->r_info))
1740 {
1741 /* Try to turn a 22-bit absolute call/jump into an 13-bit
1742 pc-relative rcall/rjmp. */
1743 case R_AVR_CALL:
1744 {
1745 bfd_vma value = symval + irel->r_addend;
1746 bfd_vma dot, gap;
1747 int distance_short_enough = 0;
1748
1749 /* Get the address of this instruction. */
1750 dot = (sec->output_section->vma
1751 + sec->output_offset + irel->r_offset);
1752
1753 /* Compute the distance from this insn to the branch target. */
1754 gap = value - dot;
1755
1756 /* If the distance is within -4094..+4098 inclusive, then we can
1757 relax this jump/call. +4098 because the call/jump target
1758 will be closer after the relaxation. */
1759 if ((int) gap >= -4094 && (int) gap <= 4098)
1760 distance_short_enough = 1;
1761
1762 /* Here we handle the wrap-around case. E.g. for a 16k device
1763 we could use a rjmp to jump from address 0x100 to 0x3d00!
1764 In order to make this work properly, we need to fill the
1765 vaiable avr_pc_wrap_around with the appropriate value.
1766 I.e. 0x4000 for a 16k device. */
1767 {
1768 /* Shrinking the code size makes the gaps larger in the
1769 case of wrap-arounds. So we use a heuristical safety
1770 margin to avoid that during relax the distance gets
1771 again too large for the short jumps. Let's assume
1772 a typical code-size reduction due to relax for a
1773 16k device of 600 bytes. So let's use twice the
1774 typical value as safety margin. */
1775 int rgap;
1776 int safety_margin;
1777
1778 int assumed_shrink = 600;
1779 if (avr_pc_wrap_around > 0x4000)
1780 assumed_shrink = 900;
1781
1782 safety_margin = 2 * assumed_shrink;
1783
1784 rgap = avr_relative_distance_considering_wrap_around (gap);
1785
1786 if (rgap >= (-4092 + safety_margin)
1787 && rgap <= (4094 - safety_margin))
1788 distance_short_enough = 1;
1789 }
1790
1791 if (distance_short_enough)
1792 {
1793 unsigned char code_msb;
1794 unsigned char code_lsb;
1795
1796 if (debug_relax)
1797 printf ("shrinking jump/call instruction at address 0x%x"
1798 " in section %s\n\n",
1799 (int) dot, sec->name);
1800
1801 /* Note that we've changed the relocs, section contents,
1802 etc. */
1803 elf_section_data (sec)->relocs = internal_relocs;
1804 elf_section_data (sec)->this_hdr.contents = contents;
1805 symtab_hdr->contents = (unsigned char *) isymbuf;
1806
1807 /* Get the instruction code for relaxing. */
1808 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset);
1809 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1810
1811 /* Mask out the relocation bits. */
1812 code_msb &= 0x94;
1813 code_lsb &= 0x0E;
1814 if (code_msb == 0x94 && code_lsb == 0x0E)
1815 {
1816 /* we are changing call -> rcall . */
1817 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1818 bfd_put_8 (abfd, 0xD0, contents + irel->r_offset + 1);
1819 }
1820 else if (code_msb == 0x94 && code_lsb == 0x0C)
1821 {
1822 /* we are changeing jump -> rjmp. */
1823 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1824 bfd_put_8 (abfd, 0xC0, contents + irel->r_offset + 1);
1825 }
1826 else
1827 abort ();
1828
1829 /* Fix the relocation's type. */
1830 irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
1831 R_AVR_13_PCREL);
1832
1833 /* Check for the vector section. There we don't want to
1834 modify the ordering! */
1835
1836 if (!strcmp (sec->name,".vectors")
1837 || !strcmp (sec->name,".jumptables"))
1838 {
1839 /* Let's insert a nop. */
1840 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
1841 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 3);
1842 }
1843 else
1844 {
1845 /* Delete two bytes of data. */
1846 if (!elf32_avr_relax_delete_bytes (abfd, sec,
1847 irel->r_offset + 2, 2))
1848 goto error_return;
1849
1850 /* That will change things, so, we should relax again.
1851 Note that this is not required, and it may be slow. */
1852 *again = TRUE;
1853 }
1854 }
1855 }
1856
1857 default:
1858 {
1859 unsigned char code_msb;
1860 unsigned char code_lsb;
1861 bfd_vma dot;
1862
1863 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1864 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset + 0);
1865
1866 /* Get the address of this instruction. */
1867 dot = (sec->output_section->vma
1868 + sec->output_offset + irel->r_offset);
1869
1870 /* Here we look for rcall/ret or call/ret sequences that could be
1871 safely replaced by rjmp/ret or jmp/ret. */
1872 if (((code_msb & 0xf0) == 0xd0)
1873 && avr_replace_call_ret_sequences)
1874 {
1875 /* This insn is a rcall. */
1876 unsigned char next_insn_msb = 0;
1877 unsigned char next_insn_lsb = 0;
1878
1879 if (irel->r_offset + 3 < sec->size)
1880 {
1881 next_insn_msb =
1882 bfd_get_8 (abfd, contents + irel->r_offset + 3);
1883 next_insn_lsb =
1884 bfd_get_8 (abfd, contents + irel->r_offset + 2);
1885 }
1886
1887 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1888 {
1889 /* The next insn is a ret. We now convert the rcall insn
1890 into a rjmp instruction. */
1891 code_msb &= 0xef;
1892 bfd_put_8 (abfd, code_msb, contents + irel->r_offset + 1);
1893 if (debug_relax)
1894 printf ("converted rcall/ret sequence at address 0x%x"
1895 " into rjmp/ret sequence. Section is %s\n\n",
1896 (int) dot, sec->name);
1897 *again = TRUE;
1898 break;
1899 }
1900 }
1901 else if ((0x94 == (code_msb & 0xfe))
1902 && (0x0e == (code_lsb & 0x0e))
1903 && avr_replace_call_ret_sequences)
1904 {
1905 /* This insn is a call. */
1906 unsigned char next_insn_msb = 0;
1907 unsigned char next_insn_lsb = 0;
1908
1909 if (irel->r_offset + 5 < sec->size)
1910 {
1911 next_insn_msb =
1912 bfd_get_8 (abfd, contents + irel->r_offset + 5);
1913 next_insn_lsb =
1914 bfd_get_8 (abfd, contents + irel->r_offset + 4);
1915 }
1916
1917 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1918 {
1919 /* The next insn is a ret. We now convert the call insn
1920 into a jmp instruction. */
1921
1922 code_lsb &= 0xfd;
1923 bfd_put_8 (abfd, code_lsb, contents + irel->r_offset);
1924 if (debug_relax)
1925 printf ("converted call/ret sequence at address 0x%x"
1926 " into jmp/ret sequence. Section is %s\n\n",
1927 (int) dot, sec->name);
1928 *again = TRUE;
1929 break;
1930 }
1931 }
1932 else if ((0xc0 == (code_msb & 0xf0))
1933 || ((0x94 == (code_msb & 0xfe))
1934 && (0x0c == (code_lsb & 0x0e))))
1935 {
1936 /* This insn is a rjmp or a jmp. */
1937 unsigned char next_insn_msb = 0;
1938 unsigned char next_insn_lsb = 0;
1939 int insn_size;
1940
1941 if (0xc0 == (code_msb & 0xf0))
1942 insn_size = 2; /* rjmp insn */
1943 else
1944 insn_size = 4; /* jmp insn */
1945
1946 if (irel->r_offset + insn_size + 1 < sec->size)
1947 {
1948 next_insn_msb =
1949 bfd_get_8 (abfd, contents + irel->r_offset
1950 + insn_size + 1);
1951 next_insn_lsb =
1952 bfd_get_8 (abfd, contents + irel->r_offset
1953 + insn_size);
1954 }
1955
1956 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1957 {
1958 /* The next insn is a ret. We possibly could delete
1959 this ret. First we need to check for preceeding
1960 sbis/sbic/sbrs or cpse "skip" instructions. */
1961
1962 int there_is_preceeding_non_skip_insn = 1;
1963 bfd_vma address_of_ret;
1964
1965 address_of_ret = dot + insn_size;
1966
1967 if (debug_relax && (insn_size == 2))
1968 printf ("found rjmp / ret sequence at address 0x%x\n",
1969 (int) dot);
1970 if (debug_relax && (insn_size == 4))
1971 printf ("found jmp / ret sequence at address 0x%x\n",
1972 (int) dot);
1973
1974 /* We have to make sure that there is a preceeding insn. */
1975 if (irel->r_offset >= 2)
1976 {
1977 unsigned char preceeding_msb;
1978 unsigned char preceeding_lsb;
1979 preceeding_msb =
1980 bfd_get_8 (abfd, contents + irel->r_offset - 1);
1981 preceeding_lsb =
1982 bfd_get_8 (abfd, contents + irel->r_offset - 2);
1983
1984 /* sbic. */
1985 if (0x99 == preceeding_msb)
1986 there_is_preceeding_non_skip_insn = 0;
1987
1988 /* sbis. */
1989 if (0x9b == preceeding_msb)
1990 there_is_preceeding_non_skip_insn = 0;
1991
1992 /* sbrc */
1993 if ((0xfc == (preceeding_msb & 0xfe)
1994 && (0x00 == (preceeding_lsb & 0x08))))
1995 there_is_preceeding_non_skip_insn = 0;
1996
1997 /* sbrs */
1998 if ((0xfe == (preceeding_msb & 0xfe)
1999 && (0x00 == (preceeding_lsb & 0x08))))
2000 there_is_preceeding_non_skip_insn = 0;
2001
2002 /* cpse */
2003 if (0x10 == (preceeding_msb & 0xfc))
2004 there_is_preceeding_non_skip_insn = 0;
2005
2006 if (there_is_preceeding_non_skip_insn == 0)
2007 if (debug_relax)
2008 printf ("preceeding skip insn prevents deletion of"
2009 " ret insn at addr 0x%x in section %s\n",
2010 (int) dot + 2, sec->name);
2011 }
2012 else
2013 {
2014 /* There is no previous instruction. */
2015 there_is_preceeding_non_skip_insn = 0;
2016 }
2017
2018 if (there_is_preceeding_non_skip_insn)
2019 {
2020 /* We now only have to make sure that there is no
2021 local label defined at the address of the ret
2022 instruction and that there is no local relocation
2023 in this section pointing to the ret. */
2024
2025 int deleting_ret_is_safe = 1;
2026 unsigned int section_offset_of_ret_insn =
2027 irel->r_offset + insn_size;
2028 Elf_Internal_Sym *isym, *isymend;
2029 unsigned int sec_shndx;
2030
2031 sec_shndx =
2032 _bfd_elf_section_from_bfd_section (abfd, sec);
2033
2034 /* Check for local symbols. */
2035 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
2036 isymend = isym + symtab_hdr->sh_info;
2037 /* PR 6019: There may not be any local symbols. */
2038 for (; isym != NULL && isym < isymend; isym++)
2039 {
2040 if (isym->st_value == section_offset_of_ret_insn
2041 && isym->st_shndx == sec_shndx)
2042 {
2043 deleting_ret_is_safe = 0;
2044 if (debug_relax)
2045 printf ("local label prevents deletion of ret "
2046 "insn at address 0x%x\n",
2047 (int) dot + insn_size);
2048 }
2049 }
2050
2051 /* Now check for global symbols. */
2052 {
2053 int symcount;
2054 struct elf_link_hash_entry **sym_hashes;
2055 struct elf_link_hash_entry **end_hashes;
2056
2057 symcount = (symtab_hdr->sh_size
2058 / sizeof (Elf32_External_Sym)
2059 - symtab_hdr->sh_info);
2060 sym_hashes = elf_sym_hashes (abfd);
2061 end_hashes = sym_hashes + symcount;
2062 for (; sym_hashes < end_hashes; sym_hashes++)
2063 {
2064 struct elf_link_hash_entry *sym_hash =
2065 *sym_hashes;
2066 if ((sym_hash->root.type == bfd_link_hash_defined
2067 || sym_hash->root.type ==
2068 bfd_link_hash_defweak)
2069 && sym_hash->root.u.def.section == sec
2070 && sym_hash->root.u.def.value == section_offset_of_ret_insn)
2071 {
2072 deleting_ret_is_safe = 0;
2073 if (debug_relax)
2074 printf ("global label prevents deletion of "
2075 "ret insn at address 0x%x\n",
2076 (int) dot + insn_size);
2077 }
2078 }
2079 }
2080 /* Now we check for relocations pointing to ret. */
2081 {
2082 Elf_Internal_Rela *irel;
2083 Elf_Internal_Rela *relend;
2084 Elf_Internal_Shdr *symtab_hdr;
2085
2086 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2087 relend = elf_section_data (sec)->relocs
2088 + sec->reloc_count;
2089
2090 for (irel = elf_section_data (sec)->relocs;
2091 irel < relend; irel++)
2092 {
2093 bfd_vma reloc_target = 0;
2094 bfd_vma symval;
2095 Elf_Internal_Sym *isymbuf = NULL;
2096
2097 /* Read this BFD's local symbols if we haven't
2098 done so already. */
2099 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
2100 {
2101 isymbuf = (Elf_Internal_Sym *)
2102 symtab_hdr->contents;
2103 if (isymbuf == NULL)
2104 isymbuf = bfd_elf_get_elf_syms
2105 (abfd,
2106 symtab_hdr,
2107 symtab_hdr->sh_info, 0,
2108 NULL, NULL, NULL);
2109 if (isymbuf == NULL)
2110 break;
2111 }
2112
2113 /* Get the value of the symbol referred to
2114 by the reloc. */
2115 if (ELF32_R_SYM (irel->r_info)
2116 < symtab_hdr->sh_info)
2117 {
2118 /* A local symbol. */
2119 Elf_Internal_Sym *isym;
2120 asection *sym_sec;
2121
2122 isym = isymbuf
2123 + ELF32_R_SYM (irel->r_info);
2124 sym_sec = bfd_section_from_elf_index
2125 (abfd, isym->st_shndx);
2126 symval = isym->st_value;
2127
2128 /* If the reloc is absolute, it will not
2129 have a symbol or section associated
2130 with it. */
2131
2132 if (sym_sec)
2133 {
2134 symval +=
2135 sym_sec->output_section->vma
2136 + sym_sec->output_offset;
2137 reloc_target = symval + irel->r_addend;
2138 }
2139 else
2140 {
2141 reloc_target = symval + irel->r_addend;
2142 /* Reference symbol is absolute. */
2143 }
2144 }
2145 /* else ... reference symbol is extern. */
2146
2147 if (address_of_ret == reloc_target)
2148 {
2149 deleting_ret_is_safe = 0;
2150 if (debug_relax)
2151 printf ("ret from "
2152 "rjmp/jmp ret sequence at address"
2153 " 0x%x could not be deleted. ret"
2154 " is target of a relocation.\n",
2155 (int) address_of_ret);
2156 }
2157 }
2158 }
2159
2160 if (deleting_ret_is_safe)
2161 {
2162 if (debug_relax)
2163 printf ("unreachable ret instruction "
2164 "at address 0x%x deleted.\n",
2165 (int) dot + insn_size);
2166
2167 /* Delete two bytes of data. */
2168 if (!elf32_avr_relax_delete_bytes (abfd, sec,
2169 irel->r_offset + insn_size, 2))
2170 goto error_return;
2171
2172 /* That will change things, so, we should relax
2173 again. Note that this is not required, and it
2174 may be slow. */
2175 *again = TRUE;
2176 break;
2177 }
2178 }
2179
2180 }
2181 }
2182 break;
2183 }
2184 }
2185 }
2186
2187 if (contents != NULL
2188 && elf_section_data (sec)->this_hdr.contents != contents)
2189 {
2190 if (! link_info->keep_memory)
2191 free (contents);
2192 else
2193 {
2194 /* Cache the section contents for elf_link_input_bfd. */
2195 elf_section_data (sec)->this_hdr.contents = contents;
2196 }
2197 }
2198
2199 if (internal_relocs != NULL
2200 && elf_section_data (sec)->relocs != internal_relocs)
2201 free (internal_relocs);
2202
2203 return TRUE;
2204
2205 error_return:
2206 if (isymbuf != NULL
2207 && symtab_hdr->contents != (unsigned char *) isymbuf)
2208 free (isymbuf);
2209 if (contents != NULL
2210 && elf_section_data (sec)->this_hdr.contents != contents)
2211 free (contents);
2212 if (internal_relocs != NULL
2213 && elf_section_data (sec)->relocs != internal_relocs)
2214 free (internal_relocs);
2215
2216 return FALSE;
2217 }
2218
2219 /* This is a version of bfd_generic_get_relocated_section_contents
2220 which uses elf32_avr_relocate_section.
2221
2222 For avr it's essentially a cut and paste taken from the H8300 port.
2223 The author of the relaxation support patch for avr had absolutely no
2224 clue what is happening here but found out that this part of the code
2225 seems to be important. */
2226
2227 static bfd_byte *
2228 elf32_avr_get_relocated_section_contents (bfd *output_bfd,
2229 struct bfd_link_info *link_info,
2230 struct bfd_link_order *link_order,
2231 bfd_byte *data,
2232 bfd_boolean relocatable,
2233 asymbol **symbols)
2234 {
2235 Elf_Internal_Shdr *symtab_hdr;
2236 asection *input_section = link_order->u.indirect.section;
2237 bfd *input_bfd = input_section->owner;
2238 asection **sections = NULL;
2239 Elf_Internal_Rela *internal_relocs = NULL;
2240 Elf_Internal_Sym *isymbuf = NULL;
2241
2242 /* We only need to handle the case of relaxing, or of having a
2243 particular set of section contents, specially. */
2244 if (relocatable
2245 || elf_section_data (input_section)->this_hdr.contents == NULL)
2246 return bfd_generic_get_relocated_section_contents (output_bfd, link_info,
2247 link_order, data,
2248 relocatable,
2249 symbols);
2250 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2251
2252 memcpy (data, elf_section_data (input_section)->this_hdr.contents,
2253 (size_t) input_section->size);
2254
2255 if ((input_section->flags & SEC_RELOC) != 0
2256 && input_section->reloc_count > 0)
2257 {
2258 asection **secpp;
2259 Elf_Internal_Sym *isym, *isymend;
2260 bfd_size_type amt;
2261
2262 internal_relocs = (_bfd_elf_link_read_relocs
2263 (input_bfd, input_section, NULL, NULL, FALSE));
2264 if (internal_relocs == NULL)
2265 goto error_return;
2266
2267 if (symtab_hdr->sh_info != 0)
2268 {
2269 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
2270 if (isymbuf == NULL)
2271 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2272 symtab_hdr->sh_info, 0,
2273 NULL, NULL, NULL);
2274 if (isymbuf == NULL)
2275 goto error_return;
2276 }
2277
2278 amt = symtab_hdr->sh_info;
2279 amt *= sizeof (asection *);
2280 sections = bfd_malloc (amt);
2281 if (sections == NULL && amt != 0)
2282 goto error_return;
2283
2284 isymend = isymbuf + symtab_hdr->sh_info;
2285 for (isym = isymbuf, secpp = sections; isym < isymend; ++isym, ++secpp)
2286 {
2287 asection *isec;
2288
2289 if (isym->st_shndx == SHN_UNDEF)
2290 isec = bfd_und_section_ptr;
2291 else if (isym->st_shndx == SHN_ABS)
2292 isec = bfd_abs_section_ptr;
2293 else if (isym->st_shndx == SHN_COMMON)
2294 isec = bfd_com_section_ptr;
2295 else
2296 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
2297
2298 *secpp = isec;
2299 }
2300
2301 if (! elf32_avr_relocate_section (output_bfd, link_info, input_bfd,
2302 input_section, data, internal_relocs,
2303 isymbuf, sections))
2304 goto error_return;
2305
2306 if (sections != NULL)
2307 free (sections);
2308 if (isymbuf != NULL
2309 && symtab_hdr->contents != (unsigned char *) isymbuf)
2310 free (isymbuf);
2311 if (elf_section_data (input_section)->relocs != internal_relocs)
2312 free (internal_relocs);
2313 }
2314
2315 return data;
2316
2317 error_return:
2318 if (sections != NULL)
2319 free (sections);
2320 if (isymbuf != NULL
2321 && symtab_hdr->contents != (unsigned char *) isymbuf)
2322 free (isymbuf);
2323 if (internal_relocs != NULL
2324 && elf_section_data (input_section)->relocs != internal_relocs)
2325 free (internal_relocs);
2326 return NULL;
2327 }
2328
2329
2330 /* Determines the hash entry name for a particular reloc. It consists of
2331 the identifier of the symbol section and the added reloc addend and
2332 symbol offset relative to the section the symbol is attached to. */
2333
2334 static char *
2335 avr_stub_name (const asection *symbol_section,
2336 const bfd_vma symbol_offset,
2337 const Elf_Internal_Rela *rela)
2338 {
2339 char *stub_name;
2340 bfd_size_type len;
2341
2342 len = 8 + 1 + 8 + 1 + 1;
2343 stub_name = bfd_malloc (len);
2344
2345 sprintf (stub_name, "%08x+%08x",
2346 symbol_section->id & 0xffffffff,
2347 (unsigned int) ((rela->r_addend & 0xffffffff) + symbol_offset));
2348
2349 return stub_name;
2350 }
2351
2352
2353 /* Add a new stub entry to the stub hash. Not all fields of the new
2354 stub entry are initialised. */
2355
2356 static struct elf32_avr_stub_hash_entry *
2357 avr_add_stub (const char *stub_name,
2358 struct elf32_avr_link_hash_table *htab)
2359 {
2360 struct elf32_avr_stub_hash_entry *hsh;
2361
2362 /* Enter this entry into the linker stub hash table. */
2363 hsh = avr_stub_hash_lookup (&htab->bstab, stub_name, TRUE, FALSE);
2364
2365 if (hsh == NULL)
2366 {
2367 (*_bfd_error_handler) (_("%B: cannot create stub entry %s"),
2368 NULL, stub_name);
2369 return NULL;
2370 }
2371
2372 hsh->stub_offset = 0;
2373 return hsh;
2374 }
2375
2376 /* We assume that there is already space allocated for the stub section
2377 contents and that before building the stubs the section size is
2378 initialized to 0. We assume that within the stub hash table entry,
2379 the absolute position of the jmp target has been written in the
2380 target_value field. We write here the offset of the generated jmp insn
2381 relative to the trampoline section start to the stub_offset entry in
2382 the stub hash table entry. */
2383
2384 static bfd_boolean
2385 avr_build_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2386 {
2387 struct elf32_avr_stub_hash_entry *hsh;
2388 struct bfd_link_info *info;
2389 struct elf32_avr_link_hash_table *htab;
2390 bfd *stub_bfd;
2391 bfd_byte *loc;
2392 bfd_vma target;
2393 bfd_vma starget;
2394
2395 /* Basic opcode */
2396 bfd_vma jmp_insn = 0x0000940c;
2397
2398 /* Massage our args to the form they really have. */
2399 hsh = avr_stub_hash_entry (bh);
2400
2401 if (!hsh->is_actually_needed)
2402 return TRUE;
2403
2404 info = (struct bfd_link_info *) in_arg;
2405
2406 htab = avr_link_hash_table (info);
2407 if (htab == NULL)
2408 return FALSE;
2409
2410 target = hsh->target_value;
2411
2412 /* Make a note of the offset within the stubs for this entry. */
2413 hsh->stub_offset = htab->stub_sec->size;
2414 loc = htab->stub_sec->contents + hsh->stub_offset;
2415
2416 stub_bfd = htab->stub_sec->owner;
2417
2418 if (debug_stubs)
2419 printf ("Building one Stub. Address: 0x%x, Offset: 0x%x\n",
2420 (unsigned int) target,
2421 (unsigned int) hsh->stub_offset);
2422
2423 /* We now have to add the information on the jump target to the bare
2424 opcode bits already set in jmp_insn. */
2425
2426 /* Check for the alignment of the address. */
2427 if (target & 1)
2428 return FALSE;
2429
2430 starget = target >> 1;
2431 jmp_insn |= ((starget & 0x10000) | ((starget << 3) & 0x1f00000)) >> 16;
2432 bfd_put_16 (stub_bfd, jmp_insn, loc);
2433 bfd_put_16 (stub_bfd, (bfd_vma) starget & 0xffff, loc + 2);
2434
2435 htab->stub_sec->size += 4;
2436
2437 /* Now add the entries in the address mapping table if there is still
2438 space left. */
2439 {
2440 unsigned int nr;
2441
2442 nr = htab->amt_entry_cnt + 1;
2443 if (nr <= htab->amt_max_entry_cnt)
2444 {
2445 htab->amt_entry_cnt = nr;
2446
2447 htab->amt_stub_offsets[nr - 1] = hsh->stub_offset;
2448 htab->amt_destination_addr[nr - 1] = target;
2449 }
2450 }
2451
2452 return TRUE;
2453 }
2454
2455 static bfd_boolean
2456 avr_mark_stub_not_to_be_necessary (struct bfd_hash_entry *bh,
2457 void *in_arg)
2458 {
2459 struct elf32_avr_stub_hash_entry *hsh;
2460 struct elf32_avr_link_hash_table *htab;
2461
2462 htab = in_arg;
2463 hsh = avr_stub_hash_entry (bh);
2464 hsh->is_actually_needed = FALSE;
2465
2466 return TRUE;
2467 }
2468
2469 static bfd_boolean
2470 avr_size_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2471 {
2472 struct elf32_avr_stub_hash_entry *hsh;
2473 struct elf32_avr_link_hash_table *htab;
2474 int size;
2475
2476 /* Massage our args to the form they really have. */
2477 hsh = avr_stub_hash_entry (bh);
2478 htab = in_arg;
2479
2480 if (hsh->is_actually_needed)
2481 size = 4;
2482 else
2483 size = 0;
2484
2485 htab->stub_sec->size += size;
2486 return TRUE;
2487 }
2488
2489 void
2490 elf32_avr_setup_params (struct bfd_link_info *info,
2491 bfd *avr_stub_bfd,
2492 asection *avr_stub_section,
2493 bfd_boolean no_stubs,
2494 bfd_boolean deb_stubs,
2495 bfd_boolean deb_relax,
2496 bfd_vma pc_wrap_around,
2497 bfd_boolean call_ret_replacement)
2498 {
2499 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2500
2501 if (htab == NULL)
2502 return;
2503 htab->stub_sec = avr_stub_section;
2504 htab->stub_bfd = avr_stub_bfd;
2505 htab->no_stubs = no_stubs;
2506
2507 debug_relax = deb_relax;
2508 debug_stubs = deb_stubs;
2509 avr_pc_wrap_around = pc_wrap_around;
2510 avr_replace_call_ret_sequences = call_ret_replacement;
2511 }
2512
2513
2514 /* Set up various things so that we can make a list of input sections
2515 for each output section included in the link. Returns -1 on error,
2516 0 when no stubs will be needed, and 1 on success. It also sets
2517 information on the stubs bfd and the stub section in the info
2518 struct. */
2519
2520 int
2521 elf32_avr_setup_section_lists (bfd *output_bfd,
2522 struct bfd_link_info *info)
2523 {
2524 bfd *input_bfd;
2525 unsigned int bfd_count;
2526 int top_id, top_index;
2527 asection *section;
2528 asection **input_list, **list;
2529 bfd_size_type amt;
2530 struct elf32_avr_link_hash_table *htab = avr_link_hash_table(info);
2531
2532 if (htab == NULL || htab->no_stubs)
2533 return 0;
2534
2535 /* Count the number of input BFDs and find the top input section id. */
2536 for (input_bfd = info->input_bfds, bfd_count = 0, top_id = 0;
2537 input_bfd != NULL;
2538 input_bfd = input_bfd->link_next)
2539 {
2540 bfd_count += 1;
2541 for (section = input_bfd->sections;
2542 section != NULL;
2543 section = section->next)
2544 if (top_id < section->id)
2545 top_id = section->id;
2546 }
2547
2548 htab->bfd_count = bfd_count;
2549
2550 /* We can't use output_bfd->section_count here to find the top output
2551 section index as some sections may have been removed, and
2552 strip_excluded_output_sections doesn't renumber the indices. */
2553 for (section = output_bfd->sections, top_index = 0;
2554 section != NULL;
2555 section = section->next)
2556 if (top_index < section->index)
2557 top_index = section->index;
2558
2559 htab->top_index = top_index;
2560 amt = sizeof (asection *) * (top_index + 1);
2561 input_list = bfd_malloc (amt);
2562 htab->input_list = input_list;
2563 if (input_list == NULL)
2564 return -1;
2565
2566 /* For sections we aren't interested in, mark their entries with a
2567 value we can check later. */
2568 list = input_list + top_index;
2569 do
2570 *list = bfd_abs_section_ptr;
2571 while (list-- != input_list);
2572
2573 for (section = output_bfd->sections;
2574 section != NULL;
2575 section = section->next)
2576 if ((section->flags & SEC_CODE) != 0)
2577 input_list[section->index] = NULL;
2578
2579 return 1;
2580 }
2581
2582
2583 /* Read in all local syms for all input bfds, and create hash entries
2584 for export stubs if we are building a multi-subspace shared lib.
2585 Returns -1 on error, 0 otherwise. */
2586
2587 static int
2588 get_local_syms (bfd *input_bfd, struct bfd_link_info *info)
2589 {
2590 unsigned int bfd_indx;
2591 Elf_Internal_Sym *local_syms, **all_local_syms;
2592 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2593
2594 if (htab == NULL)
2595 return -1;
2596
2597 /* We want to read in symbol extension records only once. To do this
2598 we need to read in the local symbols in parallel and save them for
2599 later use; so hold pointers to the local symbols in an array. */
2600 bfd_size_type amt = sizeof (Elf_Internal_Sym *) * htab->bfd_count;
2601 all_local_syms = bfd_zmalloc (amt);
2602 htab->all_local_syms = all_local_syms;
2603 if (all_local_syms == NULL)
2604 return -1;
2605
2606 /* Walk over all the input BFDs, swapping in local symbols.
2607 If we are creating a shared library, create hash entries for the
2608 export stubs. */
2609 for (bfd_indx = 0;
2610 input_bfd != NULL;
2611 input_bfd = input_bfd->link_next, bfd_indx++)
2612 {
2613 Elf_Internal_Shdr *symtab_hdr;
2614
2615 /* We'll need the symbol table in a second. */
2616 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2617 if (symtab_hdr->sh_info == 0)
2618 continue;
2619
2620 /* We need an array of the local symbols attached to the input bfd. */
2621 local_syms = (Elf_Internal_Sym *) symtab_hdr->contents;
2622 if (local_syms == NULL)
2623 {
2624 local_syms = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2625 symtab_hdr->sh_info, 0,
2626 NULL, NULL, NULL);
2627 /* Cache them for elf_link_input_bfd. */
2628 symtab_hdr->contents = (unsigned char *) local_syms;
2629 }
2630 if (local_syms == NULL)
2631 return -1;
2632
2633 all_local_syms[bfd_indx] = local_syms;
2634 }
2635
2636 return 0;
2637 }
2638
2639 #define ADD_DUMMY_STUBS_FOR_DEBUGGING 0
2640
2641 bfd_boolean
2642 elf32_avr_size_stubs (bfd *output_bfd,
2643 struct bfd_link_info *info,
2644 bfd_boolean is_prealloc_run)
2645 {
2646 struct elf32_avr_link_hash_table *htab;
2647 int stub_changed = 0;
2648
2649 htab = avr_link_hash_table (info);
2650 if (htab == NULL)
2651 return FALSE;
2652
2653 /* At this point we initialize htab->vector_base
2654 To the start of the text output section. */
2655 htab->vector_base = htab->stub_sec->output_section->vma;
2656
2657 if (get_local_syms (info->input_bfds, info))
2658 {
2659 if (htab->all_local_syms)
2660 goto error_ret_free_local;
2661 return FALSE;
2662 }
2663
2664 if (ADD_DUMMY_STUBS_FOR_DEBUGGING)
2665 {
2666 struct elf32_avr_stub_hash_entry *test;
2667
2668 test = avr_add_stub ("Hugo",htab);
2669 test->target_value = 0x123456;
2670 test->stub_offset = 13;
2671
2672 test = avr_add_stub ("Hugo2",htab);
2673 test->target_value = 0x84210;
2674 test->stub_offset = 14;
2675 }
2676
2677 while (1)
2678 {
2679 bfd *input_bfd;
2680 unsigned int bfd_indx;
2681
2682 /* We will have to re-generate the stub hash table each time anything
2683 in memory has changed. */
2684
2685 bfd_hash_traverse (&htab->bstab, avr_mark_stub_not_to_be_necessary, htab);
2686 for (input_bfd = info->input_bfds, bfd_indx = 0;
2687 input_bfd != NULL;
2688 input_bfd = input_bfd->link_next, bfd_indx++)
2689 {
2690 Elf_Internal_Shdr *symtab_hdr;
2691 asection *section;
2692 Elf_Internal_Sym *local_syms;
2693
2694 /* We'll need the symbol table in a second. */
2695 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2696 if (symtab_hdr->sh_info == 0)
2697 continue;
2698
2699 local_syms = htab->all_local_syms[bfd_indx];
2700
2701 /* Walk over each section attached to the input bfd. */
2702 for (section = input_bfd->sections;
2703 section != NULL;
2704 section = section->next)
2705 {
2706 Elf_Internal_Rela *internal_relocs, *irelaend, *irela;
2707
2708 /* If there aren't any relocs, then there's nothing more
2709 to do. */
2710 if ((section->flags & SEC_RELOC) == 0
2711 || section->reloc_count == 0)
2712 continue;
2713
2714 /* If this section is a link-once section that will be
2715 discarded, then don't create any stubs. */
2716 if (section->output_section == NULL
2717 || section->output_section->owner != output_bfd)
2718 continue;
2719
2720 /* Get the relocs. */
2721 internal_relocs
2722 = _bfd_elf_link_read_relocs (input_bfd, section, NULL, NULL,
2723 info->keep_memory);
2724 if (internal_relocs == NULL)
2725 goto error_ret_free_local;
2726
2727 /* Now examine each relocation. */
2728 irela = internal_relocs;
2729 irelaend = irela + section->reloc_count;
2730 for (; irela < irelaend; irela++)
2731 {
2732 unsigned int r_type, r_indx;
2733 struct elf32_avr_stub_hash_entry *hsh;
2734 asection *sym_sec;
2735 bfd_vma sym_value;
2736 bfd_vma destination;
2737 struct elf_link_hash_entry *hh;
2738 char *stub_name;
2739
2740 r_type = ELF32_R_TYPE (irela->r_info);
2741 r_indx = ELF32_R_SYM (irela->r_info);
2742
2743 /* Only look for 16 bit GS relocs. No other reloc will need a
2744 stub. */
2745 if (!((r_type == R_AVR_16_PM)
2746 || (r_type == R_AVR_LO8_LDI_GS)
2747 || (r_type == R_AVR_HI8_LDI_GS)))
2748 continue;
2749
2750 /* Now determine the call target, its name, value,
2751 section. */
2752 sym_sec = NULL;
2753 sym_value = 0;
2754 destination = 0;
2755 hh = NULL;
2756 if (r_indx < symtab_hdr->sh_info)
2757 {
2758 /* It's a local symbol. */
2759 Elf_Internal_Sym *sym;
2760 Elf_Internal_Shdr *hdr;
2761 unsigned int shndx;
2762
2763 sym = local_syms + r_indx;
2764 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2765 sym_value = sym->st_value;
2766 shndx = sym->st_shndx;
2767 if (shndx < elf_numsections (input_bfd))
2768 {
2769 hdr = elf_elfsections (input_bfd)[shndx];
2770 sym_sec = hdr->bfd_section;
2771 destination = (sym_value + irela->r_addend
2772 + sym_sec->output_offset
2773 + sym_sec->output_section->vma);
2774 }
2775 }
2776 else
2777 {
2778 /* It's an external symbol. */
2779 int e_indx;
2780
2781 e_indx = r_indx - symtab_hdr->sh_info;
2782 hh = elf_sym_hashes (input_bfd)[e_indx];
2783
2784 while (hh->root.type == bfd_link_hash_indirect
2785 || hh->root.type == bfd_link_hash_warning)
2786 hh = (struct elf_link_hash_entry *)
2787 (hh->root.u.i.link);
2788
2789 if (hh->root.type == bfd_link_hash_defined
2790 || hh->root.type == bfd_link_hash_defweak)
2791 {
2792 sym_sec = hh->root.u.def.section;
2793 sym_value = hh->root.u.def.value;
2794 if (sym_sec->output_section != NULL)
2795 destination = (sym_value + irela->r_addend
2796 + sym_sec->output_offset
2797 + sym_sec->output_section->vma);
2798 }
2799 else if (hh->root.type == bfd_link_hash_undefweak)
2800 {
2801 if (! info->shared)
2802 continue;
2803 }
2804 else if (hh->root.type == bfd_link_hash_undefined)
2805 {
2806 if (! (info->unresolved_syms_in_objects == RM_IGNORE
2807 && (ELF_ST_VISIBILITY (hh->other)
2808 == STV_DEFAULT)))
2809 continue;
2810 }
2811 else
2812 {
2813 bfd_set_error (bfd_error_bad_value);
2814
2815 error_ret_free_internal:
2816 if (elf_section_data (section)->relocs == NULL)
2817 free (internal_relocs);
2818 goto error_ret_free_local;
2819 }
2820 }
2821
2822 if (! avr_stub_is_required_for_16_bit_reloc
2823 (destination - htab->vector_base))
2824 {
2825 if (!is_prealloc_run)
2826 /* We are having a reloc that does't need a stub. */
2827 continue;
2828
2829 /* We don't right now know if a stub will be needed.
2830 Let's rather be on the safe side. */
2831 }
2832
2833 /* Get the name of this stub. */
2834 stub_name = avr_stub_name (sym_sec, sym_value, irela);
2835
2836 if (!stub_name)
2837 goto error_ret_free_internal;
2838
2839
2840 hsh = avr_stub_hash_lookup (&htab->bstab,
2841 stub_name,
2842 FALSE, FALSE);
2843 if (hsh != NULL)
2844 {
2845 /* The proper stub has already been created. Mark it
2846 to be used and write the possibly changed destination
2847 value. */
2848 hsh->is_actually_needed = TRUE;
2849 hsh->target_value = destination;
2850 free (stub_name);
2851 continue;
2852 }
2853
2854 hsh = avr_add_stub (stub_name, htab);
2855 if (hsh == NULL)
2856 {
2857 free (stub_name);
2858 goto error_ret_free_internal;
2859 }
2860
2861 hsh->is_actually_needed = TRUE;
2862 hsh->target_value = destination;
2863
2864 if (debug_stubs)
2865 printf ("Adding stub with destination 0x%x to the"
2866 " hash table.\n", (unsigned int) destination);
2867 if (debug_stubs)
2868 printf ("(Pre-Alloc run: %i)\n", is_prealloc_run);
2869
2870 stub_changed = TRUE;
2871 }
2872
2873 /* We're done with the internal relocs, free them. */
2874 if (elf_section_data (section)->relocs == NULL)
2875 free (internal_relocs);
2876 }
2877 }
2878
2879 /* Re-Calculate the number of needed stubs. */
2880 htab->stub_sec->size = 0;
2881 bfd_hash_traverse (&htab->bstab, avr_size_one_stub, htab);
2882
2883 if (!stub_changed)
2884 break;
2885
2886 stub_changed = FALSE;
2887 }
2888
2889 free (htab->all_local_syms);
2890 return TRUE;
2891
2892 error_ret_free_local:
2893 free (htab->all_local_syms);
2894 return FALSE;
2895 }
2896
2897
2898 /* Build all the stubs associated with the current output file. The
2899 stubs are kept in a hash table attached to the main linker hash
2900 table. We also set up the .plt entries for statically linked PIC
2901 functions here. This function is called via hppaelf_finish in the
2902 linker. */
2903
2904 bfd_boolean
2905 elf32_avr_build_stubs (struct bfd_link_info *info)
2906 {
2907 asection *stub_sec;
2908 struct bfd_hash_table *table;
2909 struct elf32_avr_link_hash_table *htab;
2910 bfd_size_type total_size = 0;
2911
2912 htab = avr_link_hash_table (info);
2913 if (htab == NULL)
2914 return FALSE;
2915
2916 /* In case that there were several stub sections: */
2917 for (stub_sec = htab->stub_bfd->sections;
2918 stub_sec != NULL;
2919 stub_sec = stub_sec->next)
2920 {
2921 bfd_size_type size;
2922
2923 /* Allocate memory to hold the linker stubs. */
2924 size = stub_sec->size;
2925 total_size += size;
2926
2927 stub_sec->contents = bfd_zalloc (htab->stub_bfd, size);
2928 if (stub_sec->contents == NULL && size != 0)
2929 return FALSE;
2930 stub_sec->size = 0;
2931 }
2932
2933 /* Allocate memory for the adress mapping table. */
2934 htab->amt_entry_cnt = 0;
2935 htab->amt_max_entry_cnt = total_size / 4;
2936 htab->amt_stub_offsets = bfd_malloc (sizeof (bfd_vma)
2937 * htab->amt_max_entry_cnt);
2938 htab->amt_destination_addr = bfd_malloc (sizeof (bfd_vma)
2939 * htab->amt_max_entry_cnt );
2940
2941 if (debug_stubs)
2942 printf ("Allocating %i entries in the AMT\n", htab->amt_max_entry_cnt);
2943
2944 /* Build the stubs as directed by the stub hash table. */
2945 table = &htab->bstab;
2946 bfd_hash_traverse (table, avr_build_one_stub, info);
2947
2948 if (debug_stubs)
2949 printf ("Final Stub section Size: %i\n", (int) htab->stub_sec->size);
2950
2951 return TRUE;
2952 }
2953
2954 #define ELF_ARCH bfd_arch_avr
2955 #define ELF_MACHINE_CODE EM_AVR
2956 #define ELF_MACHINE_ALT1 EM_AVR_OLD
2957 #define ELF_MAXPAGESIZE 1
2958
2959 #define TARGET_LITTLE_SYM bfd_elf32_avr_vec
2960 #define TARGET_LITTLE_NAME "elf32-avr"
2961
2962 #define bfd_elf32_bfd_link_hash_table_create elf32_avr_link_hash_table_create
2963 #define bfd_elf32_bfd_link_hash_table_free elf32_avr_link_hash_table_free
2964
2965 #define elf_info_to_howto avr_info_to_howto_rela
2966 #define elf_info_to_howto_rel NULL
2967 #define elf_backend_relocate_section elf32_avr_relocate_section
2968 #define elf_backend_check_relocs elf32_avr_check_relocs
2969 #define elf_backend_can_gc_sections 1
2970 #define elf_backend_rela_normal 1
2971 #define elf_backend_final_write_processing \
2972 bfd_elf_avr_final_write_processing
2973 #define elf_backend_object_p elf32_avr_object_p
2974
2975 #define bfd_elf32_bfd_relax_section elf32_avr_relax_section
2976 #define bfd_elf32_bfd_get_relocated_section_contents \
2977 elf32_avr_get_relocated_section_contents
2978
2979 #include "elf32-target.h"
GDB Binutils - Deliverables
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