]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - bfd/elf32-avr.c
projects / thirdparty / binutils-gdb.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Add AVR architectures avr25, avr31, avr35, and avr51 to match GCC.
[thirdparty/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_avr25:
1300 val = E_AVR_MACH_AVR25;
1301
1302 case bfd_mach_avr3:
1303 val = E_AVR_MACH_AVR3;
1304 break;
1305
1306 case bfd_mach_avr31:
1307 val = E_AVR_MACH_AVR31;
1308
1309 case bfd_mach_avr35:
1310 val = E_AVR_MACH_AVR35;
1311
1312 case bfd_mach_avr4:
1313 val = E_AVR_MACH_AVR4;
1314 break;
1315
1316 case bfd_mach_avr5:
1317 val = E_AVR_MACH_AVR5;
1318 break;
1319
1320 case bfd_mach_avr51:
1321 val = E_AVR_MACH_AVR51;
1322 break;
1323
1324 case bfd_mach_avr6:
1325 val = E_AVR_MACH_AVR6;
1326 break;
1327 }
1328
1329 elf_elfheader (abfd)->e_machine = EM_AVR;
1330 elf_elfheader (abfd)->e_flags &= ~ EF_AVR_MACH;
1331 elf_elfheader (abfd)->e_flags |= val;
1332 elf_elfheader (abfd)->e_flags |= EF_AVR_LINKRELAX_PREPARED;
1333 }
1334
1335 /* Set the right machine number. */
1336
1337 static bfd_boolean
1338 elf32_avr_object_p (bfd *abfd)
1339 {
1340 unsigned int e_set = bfd_mach_avr2;
1341
1342 if (elf_elfheader (abfd)->e_machine == EM_AVR
1343 || elf_elfheader (abfd)->e_machine == EM_AVR_OLD)
1344 {
1345 int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
1346
1347 switch (e_mach)
1348 {
1349 default:
1350 case E_AVR_MACH_AVR2:
1351 e_set = bfd_mach_avr2;
1352 break;
1353
1354 case E_AVR_MACH_AVR1:
1355 e_set = bfd_mach_avr1;
1356 break;
1357
1358 case E_AVR_MACH_AVR25:
1359 e_set = bfd_mach_avr25;
1360 break;
1361
1362 case E_AVR_MACH_AVR3:
1363 e_set = bfd_mach_avr3;
1364 break;
1365
1366 case E_AVR_MACH_AVR31:
1367 e_set = bfd_mach_avr31;
1368 break;
1369
1370 case E_AVR_MACH_AVR35:
1371 e_set = bfd_mach_avr35;
1372 break;
1373
1374 case E_AVR_MACH_AVR4:
1375 e_set = bfd_mach_avr4;
1376 break;
1377
1378 case E_AVR_MACH_AVR5:
1379 e_set = bfd_mach_avr5;
1380 break;
1381
1382 case E_AVR_MACH_AVR51:
1383 e_set = bfd_mach_avr51;
1384 break;
1385
1386 case E_AVR_MACH_AVR6:
1387 e_set = bfd_mach_avr6;
1388 break;
1389 }
1390 }
1391 return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
1392 e_set);
1393 }
1394
1395
1396 /* Delete some bytes from a section while changing the size of an instruction.
1397 The parameter "addr" denotes the section-relative offset pointing just
1398 behind the shrinked instruction. "addr+count" point at the first
1399 byte just behind the original unshrinked instruction. */
1400
1401 static bfd_boolean
1402 elf32_avr_relax_delete_bytes (bfd *abfd,
1403 asection *sec,
1404 bfd_vma addr,
1405 int count)
1406 {
1407 Elf_Internal_Shdr *symtab_hdr;
1408 unsigned int sec_shndx;
1409 bfd_byte *contents;
1410 Elf_Internal_Rela *irel, *irelend;
1411 Elf_Internal_Rela *irelalign;
1412 Elf_Internal_Sym *isym;
1413 Elf_Internal_Sym *isymbuf = NULL;
1414 Elf_Internal_Sym *isymend;
1415 bfd_vma toaddr;
1416 struct elf_link_hash_entry **sym_hashes;
1417 struct elf_link_hash_entry **end_hashes;
1418 unsigned int symcount;
1419
1420 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1421 sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
1422 contents = elf_section_data (sec)->this_hdr.contents;
1423
1424 /* The deletion must stop at the next ALIGN reloc for an aligment
1425 power larger than the number of bytes we are deleting. */
1426
1427 irelalign = NULL;
1428 toaddr = sec->size;
1429
1430 irel = elf_section_data (sec)->relocs;
1431 irelend = irel + sec->reloc_count;
1432
1433 /* Actually delete the bytes. */
1434 if (toaddr - addr - count > 0)
1435 memmove (contents + addr, contents + addr + count,
1436 (size_t) (toaddr - addr - count));
1437 sec->size -= count;
1438
1439 /* Adjust all the reloc addresses. */
1440 for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
1441 {
1442 bfd_vma old_reloc_address;
1443 bfd_vma shrinked_insn_address;
1444
1445 old_reloc_address = (sec->output_section->vma
1446 + sec->output_offset + irel->r_offset);
1447 shrinked_insn_address = (sec->output_section->vma
1448 + sec->output_offset + addr - count);
1449
1450 /* Get the new reloc address. */
1451 if ((irel->r_offset > addr
1452 && irel->r_offset < toaddr))
1453 {
1454 if (debug_relax)
1455 printf ("Relocation at address 0x%x needs to be moved.\n"
1456 "Old section offset: 0x%x, New section offset: 0x%x \n",
1457 (unsigned int) old_reloc_address,
1458 (unsigned int) irel->r_offset,
1459 (unsigned int) ((irel->r_offset) - count));
1460
1461 irel->r_offset -= count;
1462 }
1463
1464 }
1465
1466 /* The reloc's own addresses are now ok. However, we need to readjust
1467 the reloc's addend, i.e. the reloc's value if two conditions are met:
1468 1.) the reloc is relative to a symbol in this section that
1469 is located in front of the shrinked instruction
1470 2.) symbol plus addend end up behind the shrinked instruction.
1471
1472 The most common case where this happens are relocs relative to
1473 the section-start symbol.
1474
1475 This step needs to be done for all of the sections of the bfd. */
1476
1477 {
1478 struct bfd_section *isec;
1479
1480 for (isec = abfd->sections; isec; isec = isec->next)
1481 {
1482 bfd_vma symval;
1483 bfd_vma shrinked_insn_address;
1484
1485 shrinked_insn_address = (sec->output_section->vma
1486 + sec->output_offset + addr - count);
1487
1488 irelend = elf_section_data (isec)->relocs + isec->reloc_count;
1489 for (irel = elf_section_data (isec)->relocs;
1490 irel < irelend;
1491 irel++)
1492 {
1493 /* Read this BFD's local symbols if we haven't done
1494 so already. */
1495 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1496 {
1497 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1498 if (isymbuf == NULL)
1499 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1500 symtab_hdr->sh_info, 0,
1501 NULL, NULL, NULL);
1502 if (isymbuf == NULL)
1503 return FALSE;
1504 }
1505
1506 /* Get the value of the symbol referred to by the reloc. */
1507 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1508 {
1509 /* A local symbol. */
1510 Elf_Internal_Sym *isym;
1511 asection *sym_sec;
1512
1513 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1514 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1515 symval = isym->st_value;
1516 /* If the reloc is absolute, it will not have
1517 a symbol or section associated with it. */
1518 if (sym_sec == sec)
1519 {
1520 symval += sym_sec->output_section->vma
1521 + sym_sec->output_offset;
1522
1523 if (debug_relax)
1524 printf ("Checking if the relocation's "
1525 "addend needs corrections.\n"
1526 "Address of anchor symbol: 0x%x \n"
1527 "Address of relocation target: 0x%x \n"
1528 "Address of relaxed insn: 0x%x \n",
1529 (unsigned int) symval,
1530 (unsigned int) (symval + irel->r_addend),
1531 (unsigned int) shrinked_insn_address);
1532
1533 if (symval <= shrinked_insn_address
1534 && (symval + irel->r_addend) > shrinked_insn_address)
1535 {
1536 irel->r_addend -= count;
1537
1538 if (debug_relax)
1539 printf ("Relocation's addend needed to be fixed \n");
1540 }
1541 }
1542 /* else...Reference symbol is absolute. No adjustment needed. */
1543 }
1544 /* else...Reference symbol is extern. No need for adjusting
1545 the addend. */
1546 }
1547 }
1548 }
1549
1550 /* Adjust the local symbols defined in this section. */
1551 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
1552 isymend = isym + symtab_hdr->sh_info;
1553 for (; isym < isymend; isym++)
1554 {
1555 if (isym->st_shndx == sec_shndx
1556 && isym->st_value > addr
1557 && isym->st_value < toaddr)
1558 isym->st_value -= count;
1559 }
1560
1561 /* Now adjust the global symbols defined in this section. */
1562 symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
1563 - symtab_hdr->sh_info);
1564 sym_hashes = elf_sym_hashes (abfd);
1565 end_hashes = sym_hashes + symcount;
1566 for (; sym_hashes < end_hashes; sym_hashes++)
1567 {
1568 struct elf_link_hash_entry *sym_hash = *sym_hashes;
1569 if ((sym_hash->root.type == bfd_link_hash_defined
1570 || sym_hash->root.type == bfd_link_hash_defweak)
1571 && sym_hash->root.u.def.section == sec
1572 && sym_hash->root.u.def.value > addr
1573 && sym_hash->root.u.def.value < toaddr)
1574 {
1575 sym_hash->root.u.def.value -= count;
1576 }
1577 }
1578
1579 return TRUE;
1580 }
1581
1582 /* This function handles relaxing for the avr.
1583 Many important relaxing opportunities within functions are already
1584 realized by the compiler itself.
1585 Here we try to replace call (4 bytes) -> rcall (2 bytes)
1586 and jump -> rjmp (safes also 2 bytes).
1587 As well we now optimize seqences of
1588 - call/rcall function
1589 - ret
1590 to yield
1591 - jmp/rjmp function
1592 - ret
1593 . In case that within a sequence
1594 - jmp/rjmp label
1595 - ret
1596 the ret could no longer be reached it is optimized away. In order
1597 to check if the ret is no longer needed, it is checked that the ret's address
1598 is not the target of a branch or jump within the same section, it is checked
1599 that there is no skip instruction before the jmp/rjmp and that there
1600 is no local or global label place at the address of the ret.
1601
1602 We refrain from relaxing within sections ".vectors" and
1603 ".jumptables" in order to maintain the position of the instructions.
1604 There, however, we substitute jmp/call by a sequence rjmp,nop/rcall,nop
1605 if possible. (In future one could possibly use the space of the nop
1606 for the first instruction of the irq service function.
1607
1608 The .jumptables sections is meant to be used for a future tablejump variant
1609 for the devices with 3-byte program counter where the table itself
1610 contains 4-byte jump instructions whose relative offset must not
1611 be changed. */
1612
1613 static bfd_boolean
1614 elf32_avr_relax_section (bfd *abfd,
1615 asection *sec,
1616 struct bfd_link_info *link_info,
1617 bfd_boolean *again)
1618 {
1619 Elf_Internal_Shdr *symtab_hdr;
1620 Elf_Internal_Rela *internal_relocs;
1621 Elf_Internal_Rela *irel, *irelend;
1622 bfd_byte *contents = NULL;
1623 Elf_Internal_Sym *isymbuf = NULL;
1624 static asection *last_input_section = NULL;
1625 static Elf_Internal_Rela *last_reloc = NULL;
1626 struct elf32_avr_link_hash_table *htab;
1627
1628 htab = avr_link_hash_table (link_info);
1629 if (htab == NULL)
1630 return FALSE;
1631
1632 /* Assume nothing changes. */
1633 *again = FALSE;
1634
1635 if ((!htab->no_stubs) && (sec == htab->stub_sec))
1636 {
1637 /* We are just relaxing the stub section.
1638 Let's calculate the size needed again. */
1639 bfd_size_type last_estimated_stub_section_size = htab->stub_sec->size;
1640
1641 if (debug_relax)
1642 printf ("Relaxing the stub section. Size prior to this pass: %i\n",
1643 (int) last_estimated_stub_section_size);
1644
1645 elf32_avr_size_stubs (htab->stub_sec->output_section->owner,
1646 link_info, FALSE);
1647
1648 /* Check if the number of trampolines changed. */
1649 if (last_estimated_stub_section_size != htab->stub_sec->size)
1650 *again = TRUE;
1651
1652 if (debug_relax)
1653 printf ("Size of stub section after this pass: %i\n",
1654 (int) htab->stub_sec->size);
1655
1656 return TRUE;
1657 }
1658
1659 /* We don't have to do anything for a relocatable link, if
1660 this section does not have relocs, or if this is not a
1661 code section. */
1662 if (link_info->relocatable
1663 || (sec->flags & SEC_RELOC) == 0
1664 || sec->reloc_count == 0
1665 || (sec->flags & SEC_CODE) == 0)
1666 return TRUE;
1667
1668 /* Check if the object file to relax uses internal symbols so that we
1669 could fix up the relocations. */
1670 if (!(elf_elfheader (abfd)->e_flags & EF_AVR_LINKRELAX_PREPARED))
1671 return TRUE;
1672
1673 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1674
1675 /* Get a copy of the native relocations. */
1676 internal_relocs = (_bfd_elf_link_read_relocs
1677 (abfd, sec, NULL, NULL, link_info->keep_memory));
1678 if (internal_relocs == NULL)
1679 goto error_return;
1680
1681 if (sec != last_input_section)
1682 last_reloc = NULL;
1683
1684 last_input_section = sec;
1685
1686 /* Walk through the relocs looking for relaxing opportunities. */
1687 irelend = internal_relocs + sec->reloc_count;
1688 for (irel = internal_relocs; irel < irelend; irel++)
1689 {
1690 bfd_vma symval;
1691
1692 if ( ELF32_R_TYPE (irel->r_info) != R_AVR_13_PCREL
1693 && ELF32_R_TYPE (irel->r_info) != R_AVR_7_PCREL
1694 && ELF32_R_TYPE (irel->r_info) != R_AVR_CALL)
1695 continue;
1696
1697 /* Get the section contents if we haven't done so already. */
1698 if (contents == NULL)
1699 {
1700 /* Get cached copy if it exists. */
1701 if (elf_section_data (sec)->this_hdr.contents != NULL)
1702 contents = elf_section_data (sec)->this_hdr.contents;
1703 else
1704 {
1705 /* Go get them off disk. */
1706 if (! bfd_malloc_and_get_section (abfd, sec, &contents))
1707 goto error_return;
1708 }
1709 }
1710
1711 /* Read this BFD's local symbols if we haven't done so already. */
1712 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
1713 {
1714 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
1715 if (isymbuf == NULL)
1716 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
1717 symtab_hdr->sh_info, 0,
1718 NULL, NULL, NULL);
1719 if (isymbuf == NULL)
1720 goto error_return;
1721 }
1722
1723
1724 /* Get the value of the symbol referred to by the reloc. */
1725 if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
1726 {
1727 /* A local symbol. */
1728 Elf_Internal_Sym *isym;
1729 asection *sym_sec;
1730
1731 isym = isymbuf + ELF32_R_SYM (irel->r_info);
1732 sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
1733 symval = isym->st_value;
1734 /* If the reloc is absolute, it will not have
1735 a symbol or section associated with it. */
1736 if (sym_sec)
1737 symval += sym_sec->output_section->vma
1738 + sym_sec->output_offset;
1739 }
1740 else
1741 {
1742 unsigned long indx;
1743 struct elf_link_hash_entry *h;
1744
1745 /* An external symbol. */
1746 indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
1747 h = elf_sym_hashes (abfd)[indx];
1748 BFD_ASSERT (h != NULL);
1749 if (h->root.type != bfd_link_hash_defined
1750 && h->root.type != bfd_link_hash_defweak)
1751 /* This appears to be a reference to an undefined
1752 symbol. Just ignore it--it will be caught by the
1753 regular reloc processing. */
1754 continue;
1755
1756 symval = (h->root.u.def.value
1757 + h->root.u.def.section->output_section->vma
1758 + h->root.u.def.section->output_offset);
1759 }
1760
1761 /* For simplicity of coding, we are going to modify the section
1762 contents, the section relocs, and the BFD symbol table. We
1763 must tell the rest of the code not to free up this
1764 information. It would be possible to instead create a table
1765 of changes which have to be made, as is done in coff-mips.c;
1766 that would be more work, but would require less memory when
1767 the linker is run. */
1768 switch (ELF32_R_TYPE (irel->r_info))
1769 {
1770 /* Try to turn a 22-bit absolute call/jump into an 13-bit
1771 pc-relative rcall/rjmp. */
1772 case R_AVR_CALL:
1773 {
1774 bfd_vma value = symval + irel->r_addend;
1775 bfd_vma dot, gap;
1776 int distance_short_enough = 0;
1777
1778 /* Get the address of this instruction. */
1779 dot = (sec->output_section->vma
1780 + sec->output_offset + irel->r_offset);
1781
1782 /* Compute the distance from this insn to the branch target. */
1783 gap = value - dot;
1784
1785 /* If the distance is within -4094..+4098 inclusive, then we can
1786 relax this jump/call. +4098 because the call/jump target
1787 will be closer after the relaxation. */
1788 if ((int) gap >= -4094 && (int) gap <= 4098)
1789 distance_short_enough = 1;
1790
1791 /* Here we handle the wrap-around case. E.g. for a 16k device
1792 we could use a rjmp to jump from address 0x100 to 0x3d00!
1793 In order to make this work properly, we need to fill the
1794 vaiable avr_pc_wrap_around with the appropriate value.
1795 I.e. 0x4000 for a 16k device. */
1796 {
1797 /* Shrinking the code size makes the gaps larger in the
1798 case of wrap-arounds. So we use a heuristical safety
1799 margin to avoid that during relax the distance gets
1800 again too large for the short jumps. Let's assume
1801 a typical code-size reduction due to relax for a
1802 16k device of 600 bytes. So let's use twice the
1803 typical value as safety margin. */
1804 int rgap;
1805 int safety_margin;
1806
1807 int assumed_shrink = 600;
1808 if (avr_pc_wrap_around > 0x4000)
1809 assumed_shrink = 900;
1810
1811 safety_margin = 2 * assumed_shrink;
1812
1813 rgap = avr_relative_distance_considering_wrap_around (gap);
1814
1815 if (rgap >= (-4092 + safety_margin)
1816 && rgap <= (4094 - safety_margin))
1817 distance_short_enough = 1;
1818 }
1819
1820 if (distance_short_enough)
1821 {
1822 unsigned char code_msb;
1823 unsigned char code_lsb;
1824
1825 if (debug_relax)
1826 printf ("shrinking jump/call instruction at address 0x%x"
1827 " in section %s\n\n",
1828 (int) dot, sec->name);
1829
1830 /* Note that we've changed the relocs, section contents,
1831 etc. */
1832 elf_section_data (sec)->relocs = internal_relocs;
1833 elf_section_data (sec)->this_hdr.contents = contents;
1834 symtab_hdr->contents = (unsigned char *) isymbuf;
1835
1836 /* Get the instruction code for relaxing. */
1837 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset);
1838 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1839
1840 /* Mask out the relocation bits. */
1841 code_msb &= 0x94;
1842 code_lsb &= 0x0E;
1843 if (code_msb == 0x94 && code_lsb == 0x0E)
1844 {
1845 /* we are changing call -> rcall . */
1846 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1847 bfd_put_8 (abfd, 0xD0, contents + irel->r_offset + 1);
1848 }
1849 else if (code_msb == 0x94 && code_lsb == 0x0C)
1850 {
1851 /* we are changeing jump -> rjmp. */
1852 bfd_put_8 (abfd, 0x00, contents + irel->r_offset);
1853 bfd_put_8 (abfd, 0xC0, contents + irel->r_offset + 1);
1854 }
1855 else
1856 abort ();
1857
1858 /* Fix the relocation's type. */
1859 irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
1860 R_AVR_13_PCREL);
1861
1862 /* Check for the vector section. There we don't want to
1863 modify the ordering! */
1864
1865 if (!strcmp (sec->name,".vectors")
1866 || !strcmp (sec->name,".jumptables"))
1867 {
1868 /* Let's insert a nop. */
1869 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
1870 bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 3);
1871 }
1872 else
1873 {
1874 /* Delete two bytes of data. */
1875 if (!elf32_avr_relax_delete_bytes (abfd, sec,
1876 irel->r_offset + 2, 2))
1877 goto error_return;
1878
1879 /* That will change things, so, we should relax again.
1880 Note that this is not required, and it may be slow. */
1881 *again = TRUE;
1882 }
1883 }
1884 }
1885
1886 default:
1887 {
1888 unsigned char code_msb;
1889 unsigned char code_lsb;
1890 bfd_vma dot;
1891
1892 code_msb = bfd_get_8 (abfd, contents + irel->r_offset + 1);
1893 code_lsb = bfd_get_8 (abfd, contents + irel->r_offset + 0);
1894
1895 /* Get the address of this instruction. */
1896 dot = (sec->output_section->vma
1897 + sec->output_offset + irel->r_offset);
1898
1899 /* Here we look for rcall/ret or call/ret sequences that could be
1900 safely replaced by rjmp/ret or jmp/ret. */
1901 if (((code_msb & 0xf0) == 0xd0)
1902 && avr_replace_call_ret_sequences)
1903 {
1904 /* This insn is a rcall. */
1905 unsigned char next_insn_msb = 0;
1906 unsigned char next_insn_lsb = 0;
1907
1908 if (irel->r_offset + 3 < sec->size)
1909 {
1910 next_insn_msb =
1911 bfd_get_8 (abfd, contents + irel->r_offset + 3);
1912 next_insn_lsb =
1913 bfd_get_8 (abfd, contents + irel->r_offset + 2);
1914 }
1915
1916 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1917 {
1918 /* The next insn is a ret. We now convert the rcall insn
1919 into a rjmp instruction. */
1920 code_msb &= 0xef;
1921 bfd_put_8 (abfd, code_msb, contents + irel->r_offset + 1);
1922 if (debug_relax)
1923 printf ("converted rcall/ret sequence at address 0x%x"
1924 " into rjmp/ret sequence. Section is %s\n\n",
1925 (int) dot, sec->name);
1926 *again = TRUE;
1927 break;
1928 }
1929 }
1930 else if ((0x94 == (code_msb & 0xfe))
1931 && (0x0e == (code_lsb & 0x0e))
1932 && avr_replace_call_ret_sequences)
1933 {
1934 /* This insn is a call. */
1935 unsigned char next_insn_msb = 0;
1936 unsigned char next_insn_lsb = 0;
1937
1938 if (irel->r_offset + 5 < sec->size)
1939 {
1940 next_insn_msb =
1941 bfd_get_8 (abfd, contents + irel->r_offset + 5);
1942 next_insn_lsb =
1943 bfd_get_8 (abfd, contents + irel->r_offset + 4);
1944 }
1945
1946 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1947 {
1948 /* The next insn is a ret. We now convert the call insn
1949 into a jmp instruction. */
1950
1951 code_lsb &= 0xfd;
1952 bfd_put_8 (abfd, code_lsb, contents + irel->r_offset);
1953 if (debug_relax)
1954 printf ("converted call/ret sequence at address 0x%x"
1955 " into jmp/ret sequence. Section is %s\n\n",
1956 (int) dot, sec->name);
1957 *again = TRUE;
1958 break;
1959 }
1960 }
1961 else if ((0xc0 == (code_msb & 0xf0))
1962 || ((0x94 == (code_msb & 0xfe))
1963 && (0x0c == (code_lsb & 0x0e))))
1964 {
1965 /* This insn is a rjmp or a jmp. */
1966 unsigned char next_insn_msb = 0;
1967 unsigned char next_insn_lsb = 0;
1968 int insn_size;
1969
1970 if (0xc0 == (code_msb & 0xf0))
1971 insn_size = 2; /* rjmp insn */
1972 else
1973 insn_size = 4; /* jmp insn */
1974
1975 if (irel->r_offset + insn_size + 1 < sec->size)
1976 {
1977 next_insn_msb =
1978 bfd_get_8 (abfd, contents + irel->r_offset
1979 + insn_size + 1);
1980 next_insn_lsb =
1981 bfd_get_8 (abfd, contents + irel->r_offset
1982 + insn_size);
1983 }
1984
1985 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
1986 {
1987 /* The next insn is a ret. We possibly could delete
1988 this ret. First we need to check for preceeding
1989 sbis/sbic/sbrs or cpse "skip" instructions. */
1990
1991 int there_is_preceeding_non_skip_insn = 1;
1992 bfd_vma address_of_ret;
1993
1994 address_of_ret = dot + insn_size;
1995
1996 if (debug_relax && (insn_size == 2))
1997 printf ("found rjmp / ret sequence at address 0x%x\n",
1998 (int) dot);
1999 if (debug_relax && (insn_size == 4))
2000 printf ("found jmp / ret sequence at address 0x%x\n",
2001 (int) dot);
2002
2003 /* We have to make sure that there is a preceeding insn. */
2004 if (irel->r_offset >= 2)
2005 {
2006 unsigned char preceeding_msb;
2007 unsigned char preceeding_lsb;
2008 preceeding_msb =
2009 bfd_get_8 (abfd, contents + irel->r_offset - 1);
2010 preceeding_lsb =
2011 bfd_get_8 (abfd, contents + irel->r_offset - 2);
2012
2013 /* sbic. */
2014 if (0x99 == preceeding_msb)
2015 there_is_preceeding_non_skip_insn = 0;
2016
2017 /* sbis. */
2018 if (0x9b == preceeding_msb)
2019 there_is_preceeding_non_skip_insn = 0;
2020
2021 /* sbrc */
2022 if ((0xfc == (preceeding_msb & 0xfe)
2023 && (0x00 == (preceeding_lsb & 0x08))))
2024 there_is_preceeding_non_skip_insn = 0;
2025
2026 /* sbrs */
2027 if ((0xfe == (preceeding_msb & 0xfe)
2028 && (0x00 == (preceeding_lsb & 0x08))))
2029 there_is_preceeding_non_skip_insn = 0;
2030
2031 /* cpse */
2032 if (0x10 == (preceeding_msb & 0xfc))
2033 there_is_preceeding_non_skip_insn = 0;
2034
2035 if (there_is_preceeding_non_skip_insn == 0)
2036 if (debug_relax)
2037 printf ("preceeding skip insn prevents deletion of"
2038 " ret insn at addr 0x%x in section %s\n",
2039 (int) dot + 2, sec->name);
2040 }
2041 else
2042 {
2043 /* There is no previous instruction. */
2044 there_is_preceeding_non_skip_insn = 0;
2045 }
2046
2047 if (there_is_preceeding_non_skip_insn)
2048 {
2049 /* We now only have to make sure that there is no
2050 local label defined at the address of the ret
2051 instruction and that there is no local relocation
2052 in this section pointing to the ret. */
2053
2054 int deleting_ret_is_safe = 1;
2055 unsigned int section_offset_of_ret_insn =
2056 irel->r_offset + insn_size;
2057 Elf_Internal_Sym *isym, *isymend;
2058 unsigned int sec_shndx;
2059
2060 sec_shndx =
2061 _bfd_elf_section_from_bfd_section (abfd, sec);
2062
2063 /* Check for local symbols. */
2064 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
2065 isymend = isym + symtab_hdr->sh_info;
2066 /* PR 6019: There may not be any local symbols. */
2067 for (; isym != NULL && isym < isymend; isym++)
2068 {
2069 if (isym->st_value == section_offset_of_ret_insn
2070 && isym->st_shndx == sec_shndx)
2071 {
2072 deleting_ret_is_safe = 0;
2073 if (debug_relax)
2074 printf ("local label prevents deletion of ret "
2075 "insn at address 0x%x\n",
2076 (int) dot + insn_size);
2077 }
2078 }
2079
2080 /* Now check for global symbols. */
2081 {
2082 int symcount;
2083 struct elf_link_hash_entry **sym_hashes;
2084 struct elf_link_hash_entry **end_hashes;
2085
2086 symcount = (symtab_hdr->sh_size
2087 / sizeof (Elf32_External_Sym)
2088 - symtab_hdr->sh_info);
2089 sym_hashes = elf_sym_hashes (abfd);
2090 end_hashes = sym_hashes + symcount;
2091 for (; sym_hashes < end_hashes; sym_hashes++)
2092 {
2093 struct elf_link_hash_entry *sym_hash =
2094 *sym_hashes;
2095 if ((sym_hash->root.type == bfd_link_hash_defined
2096 || sym_hash->root.type ==
2097 bfd_link_hash_defweak)
2098 && sym_hash->root.u.def.section == sec
2099 && sym_hash->root.u.def.value == section_offset_of_ret_insn)
2100 {
2101 deleting_ret_is_safe = 0;
2102 if (debug_relax)
2103 printf ("global label prevents deletion of "
2104 "ret insn at address 0x%x\n",
2105 (int) dot + insn_size);
2106 }
2107 }
2108 }
2109 /* Now we check for relocations pointing to ret. */
2110 {
2111 Elf_Internal_Rela *irel;
2112 Elf_Internal_Rela *relend;
2113 Elf_Internal_Shdr *symtab_hdr;
2114
2115 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2116 relend = elf_section_data (sec)->relocs
2117 + sec->reloc_count;
2118
2119 for (irel = elf_section_data (sec)->relocs;
2120 irel < relend; irel++)
2121 {
2122 bfd_vma reloc_target = 0;
2123 bfd_vma symval;
2124 Elf_Internal_Sym *isymbuf = NULL;
2125
2126 /* Read this BFD's local symbols if we haven't
2127 done so already. */
2128 if (isymbuf == NULL && symtab_hdr->sh_info != 0)
2129 {
2130 isymbuf = (Elf_Internal_Sym *)
2131 symtab_hdr->contents;
2132 if (isymbuf == NULL)
2133 isymbuf = bfd_elf_get_elf_syms
2134 (abfd,
2135 symtab_hdr,
2136 symtab_hdr->sh_info, 0,
2137 NULL, NULL, NULL);
2138 if (isymbuf == NULL)
2139 break;
2140 }
2141
2142 /* Get the value of the symbol referred to
2143 by the reloc. */
2144 if (ELF32_R_SYM (irel->r_info)
2145 < symtab_hdr->sh_info)
2146 {
2147 /* A local symbol. */
2148 Elf_Internal_Sym *isym;
2149 asection *sym_sec;
2150
2151 isym = isymbuf
2152 + ELF32_R_SYM (irel->r_info);
2153 sym_sec = bfd_section_from_elf_index
2154 (abfd, isym->st_shndx);
2155 symval = isym->st_value;
2156
2157 /* If the reloc is absolute, it will not
2158 have a symbol or section associated
2159 with it. */
2160
2161 if (sym_sec)
2162 {
2163 symval +=
2164 sym_sec->output_section->vma
2165 + sym_sec->output_offset;
2166 reloc_target = symval + irel->r_addend;
2167 }
2168 else
2169 {
2170 reloc_target = symval + irel->r_addend;
2171 /* Reference symbol is absolute. */
2172 }
2173 }
2174 /* else ... reference symbol is extern. */
2175
2176 if (address_of_ret == reloc_target)
2177 {
2178 deleting_ret_is_safe = 0;
2179 if (debug_relax)
2180 printf ("ret from "
2181 "rjmp/jmp ret sequence at address"
2182 " 0x%x could not be deleted. ret"
2183 " is target of a relocation.\n",
2184 (int) address_of_ret);
2185 }
2186 }
2187 }
2188
2189 if (deleting_ret_is_safe)
2190 {
2191 if (debug_relax)
2192 printf ("unreachable ret instruction "
2193 "at address 0x%x deleted.\n",
2194 (int) dot + insn_size);
2195
2196 /* Delete two bytes of data. */
2197 if (!elf32_avr_relax_delete_bytes (abfd, sec,
2198 irel->r_offset + insn_size, 2))
2199 goto error_return;
2200
2201 /* That will change things, so, we should relax
2202 again. Note that this is not required, and it
2203 may be slow. */
2204 *again = TRUE;
2205 break;
2206 }
2207 }
2208
2209 }
2210 }
2211 break;
2212 }
2213 }
2214 }
2215
2216 if (contents != NULL
2217 && elf_section_data (sec)->this_hdr.contents != contents)
2218 {
2219 if (! link_info->keep_memory)
2220 free (contents);
2221 else
2222 {
2223 /* Cache the section contents for elf_link_input_bfd. */
2224 elf_section_data (sec)->this_hdr.contents = contents;
2225 }
2226 }
2227
2228 if (internal_relocs != NULL
2229 && elf_section_data (sec)->relocs != internal_relocs)
2230 free (internal_relocs);
2231
2232 return TRUE;
2233
2234 error_return:
2235 if (isymbuf != NULL
2236 && symtab_hdr->contents != (unsigned char *) isymbuf)
2237 free (isymbuf);
2238 if (contents != NULL
2239 && elf_section_data (sec)->this_hdr.contents != contents)
2240 free (contents);
2241 if (internal_relocs != NULL
2242 && elf_section_data (sec)->relocs != internal_relocs)
2243 free (internal_relocs);
2244
2245 return FALSE;
2246 }
2247
2248 /* This is a version of bfd_generic_get_relocated_section_contents
2249 which uses elf32_avr_relocate_section.
2250
2251 For avr it's essentially a cut and paste taken from the H8300 port.
2252 The author of the relaxation support patch for avr had absolutely no
2253 clue what is happening here but found out that this part of the code
2254 seems to be important. */
2255
2256 static bfd_byte *
2257 elf32_avr_get_relocated_section_contents (bfd *output_bfd,
2258 struct bfd_link_info *link_info,
2259 struct bfd_link_order *link_order,
2260 bfd_byte *data,
2261 bfd_boolean relocatable,
2262 asymbol **symbols)
2263 {
2264 Elf_Internal_Shdr *symtab_hdr;
2265 asection *input_section = link_order->u.indirect.section;
2266 bfd *input_bfd = input_section->owner;
2267 asection **sections = NULL;
2268 Elf_Internal_Rela *internal_relocs = NULL;
2269 Elf_Internal_Sym *isymbuf = NULL;
2270
2271 /* We only need to handle the case of relaxing, or of having a
2272 particular set of section contents, specially. */
2273 if (relocatable
2274 || elf_section_data (input_section)->this_hdr.contents == NULL)
2275 return bfd_generic_get_relocated_section_contents (output_bfd, link_info,
2276 link_order, data,
2277 relocatable,
2278 symbols);
2279 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2280
2281 memcpy (data, elf_section_data (input_section)->this_hdr.contents,
2282 (size_t) input_section->size);
2283
2284 if ((input_section->flags & SEC_RELOC) != 0
2285 && input_section->reloc_count > 0)
2286 {
2287 asection **secpp;
2288 Elf_Internal_Sym *isym, *isymend;
2289 bfd_size_type amt;
2290
2291 internal_relocs = (_bfd_elf_link_read_relocs
2292 (input_bfd, input_section, NULL, NULL, FALSE));
2293 if (internal_relocs == NULL)
2294 goto error_return;
2295
2296 if (symtab_hdr->sh_info != 0)
2297 {
2298 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
2299 if (isymbuf == NULL)
2300 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2301 symtab_hdr->sh_info, 0,
2302 NULL, NULL, NULL);
2303 if (isymbuf == NULL)
2304 goto error_return;
2305 }
2306
2307 amt = symtab_hdr->sh_info;
2308 amt *= sizeof (asection *);
2309 sections = bfd_malloc (amt);
2310 if (sections == NULL && amt != 0)
2311 goto error_return;
2312
2313 isymend = isymbuf + symtab_hdr->sh_info;
2314 for (isym = isymbuf, secpp = sections; isym < isymend; ++isym, ++secpp)
2315 {
2316 asection *isec;
2317
2318 if (isym->st_shndx == SHN_UNDEF)
2319 isec = bfd_und_section_ptr;
2320 else if (isym->st_shndx == SHN_ABS)
2321 isec = bfd_abs_section_ptr;
2322 else if (isym->st_shndx == SHN_COMMON)
2323 isec = bfd_com_section_ptr;
2324 else
2325 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
2326
2327 *secpp = isec;
2328 }
2329
2330 if (! elf32_avr_relocate_section (output_bfd, link_info, input_bfd,
2331 input_section, data, internal_relocs,
2332 isymbuf, sections))
2333 goto error_return;
2334
2335 if (sections != NULL)
2336 free (sections);
2337 if (isymbuf != NULL
2338 && symtab_hdr->contents != (unsigned char *) isymbuf)
2339 free (isymbuf);
2340 if (elf_section_data (input_section)->relocs != internal_relocs)
2341 free (internal_relocs);
2342 }
2343
2344 return data;
2345
2346 error_return:
2347 if (sections != NULL)
2348 free (sections);
2349 if (isymbuf != NULL
2350 && symtab_hdr->contents != (unsigned char *) isymbuf)
2351 free (isymbuf);
2352 if (internal_relocs != NULL
2353 && elf_section_data (input_section)->relocs != internal_relocs)
2354 free (internal_relocs);
2355 return NULL;
2356 }
2357
2358
2359 /* Determines the hash entry name for a particular reloc. It consists of
2360 the identifier of the symbol section and the added reloc addend and
2361 symbol offset relative to the section the symbol is attached to. */
2362
2363 static char *
2364 avr_stub_name (const asection *symbol_section,
2365 const bfd_vma symbol_offset,
2366 const Elf_Internal_Rela *rela)
2367 {
2368 char *stub_name;
2369 bfd_size_type len;
2370
2371 len = 8 + 1 + 8 + 1 + 1;
2372 stub_name = bfd_malloc (len);
2373
2374 sprintf (stub_name, "%08x+%08x",
2375 symbol_section->id & 0xffffffff,
2376 (unsigned int) ((rela->r_addend & 0xffffffff) + symbol_offset));
2377
2378 return stub_name;
2379 }
2380
2381
2382 /* Add a new stub entry to the stub hash. Not all fields of the new
2383 stub entry are initialised. */
2384
2385 static struct elf32_avr_stub_hash_entry *
2386 avr_add_stub (const char *stub_name,
2387 struct elf32_avr_link_hash_table *htab)
2388 {
2389 struct elf32_avr_stub_hash_entry *hsh;
2390
2391 /* Enter this entry into the linker stub hash table. */
2392 hsh = avr_stub_hash_lookup (&htab->bstab, stub_name, TRUE, FALSE);
2393
2394 if (hsh == NULL)
2395 {
2396 (*_bfd_error_handler) (_("%B: cannot create stub entry %s"),
2397 NULL, stub_name);
2398 return NULL;
2399 }
2400
2401 hsh->stub_offset = 0;
2402 return hsh;
2403 }
2404
2405 /* We assume that there is already space allocated for the stub section
2406 contents and that before building the stubs the section size is
2407 initialized to 0. We assume that within the stub hash table entry,
2408 the absolute position of the jmp target has been written in the
2409 target_value field. We write here the offset of the generated jmp insn
2410 relative to the trampoline section start to the stub_offset entry in
2411 the stub hash table entry. */
2412
2413 static bfd_boolean
2414 avr_build_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2415 {
2416 struct elf32_avr_stub_hash_entry *hsh;
2417 struct bfd_link_info *info;
2418 struct elf32_avr_link_hash_table *htab;
2419 bfd *stub_bfd;
2420 bfd_byte *loc;
2421 bfd_vma target;
2422 bfd_vma starget;
2423
2424 /* Basic opcode */
2425 bfd_vma jmp_insn = 0x0000940c;
2426
2427 /* Massage our args to the form they really have. */
2428 hsh = avr_stub_hash_entry (bh);
2429
2430 if (!hsh->is_actually_needed)
2431 return TRUE;
2432
2433 info = (struct bfd_link_info *) in_arg;
2434
2435 htab = avr_link_hash_table (info);
2436 if (htab == NULL)
2437 return FALSE;
2438
2439 target = hsh->target_value;
2440
2441 /* Make a note of the offset within the stubs for this entry. */
2442 hsh->stub_offset = htab->stub_sec->size;
2443 loc = htab->stub_sec->contents + hsh->stub_offset;
2444
2445 stub_bfd = htab->stub_sec->owner;
2446
2447 if (debug_stubs)
2448 printf ("Building one Stub. Address: 0x%x, Offset: 0x%x\n",
2449 (unsigned int) target,
2450 (unsigned int) hsh->stub_offset);
2451
2452 /* We now have to add the information on the jump target to the bare
2453 opcode bits already set in jmp_insn. */
2454
2455 /* Check for the alignment of the address. */
2456 if (target & 1)
2457 return FALSE;
2458
2459 starget = target >> 1;
2460 jmp_insn |= ((starget & 0x10000) | ((starget << 3) & 0x1f00000)) >> 16;
2461 bfd_put_16 (stub_bfd, jmp_insn, loc);
2462 bfd_put_16 (stub_bfd, (bfd_vma) starget & 0xffff, loc + 2);
2463
2464 htab->stub_sec->size += 4;
2465
2466 /* Now add the entries in the address mapping table if there is still
2467 space left. */
2468 {
2469 unsigned int nr;
2470
2471 nr = htab->amt_entry_cnt + 1;
2472 if (nr <= htab->amt_max_entry_cnt)
2473 {
2474 htab->amt_entry_cnt = nr;
2475
2476 htab->amt_stub_offsets[nr - 1] = hsh->stub_offset;
2477 htab->amt_destination_addr[nr - 1] = target;
2478 }
2479 }
2480
2481 return TRUE;
2482 }
2483
2484 static bfd_boolean
2485 avr_mark_stub_not_to_be_necessary (struct bfd_hash_entry *bh,
2486 void *in_arg)
2487 {
2488 struct elf32_avr_stub_hash_entry *hsh;
2489 struct elf32_avr_link_hash_table *htab;
2490
2491 htab = in_arg;
2492 hsh = avr_stub_hash_entry (bh);
2493 hsh->is_actually_needed = FALSE;
2494
2495 return TRUE;
2496 }
2497
2498 static bfd_boolean
2499 avr_size_one_stub (struct bfd_hash_entry *bh, void *in_arg)
2500 {
2501 struct elf32_avr_stub_hash_entry *hsh;
2502 struct elf32_avr_link_hash_table *htab;
2503 int size;
2504
2505 /* Massage our args to the form they really have. */
2506 hsh = avr_stub_hash_entry (bh);
2507 htab = in_arg;
2508
2509 if (hsh->is_actually_needed)
2510 size = 4;
2511 else
2512 size = 0;
2513
2514 htab->stub_sec->size += size;
2515 return TRUE;
2516 }
2517
2518 void
2519 elf32_avr_setup_params (struct bfd_link_info *info,
2520 bfd *avr_stub_bfd,
2521 asection *avr_stub_section,
2522 bfd_boolean no_stubs,
2523 bfd_boolean deb_stubs,
2524 bfd_boolean deb_relax,
2525 bfd_vma pc_wrap_around,
2526 bfd_boolean call_ret_replacement)
2527 {
2528 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2529
2530 if (htab == NULL)
2531 return;
2532 htab->stub_sec = avr_stub_section;
2533 htab->stub_bfd = avr_stub_bfd;
2534 htab->no_stubs = no_stubs;
2535
2536 debug_relax = deb_relax;
2537 debug_stubs = deb_stubs;
2538 avr_pc_wrap_around = pc_wrap_around;
2539 avr_replace_call_ret_sequences = call_ret_replacement;
2540 }
2541
2542
2543 /* Set up various things so that we can make a list of input sections
2544 for each output section included in the link. Returns -1 on error,
2545 0 when no stubs will be needed, and 1 on success. It also sets
2546 information on the stubs bfd and the stub section in the info
2547 struct. */
2548
2549 int
2550 elf32_avr_setup_section_lists (bfd *output_bfd,
2551 struct bfd_link_info *info)
2552 {
2553 bfd *input_bfd;
2554 unsigned int bfd_count;
2555 int top_id, top_index;
2556 asection *section;
2557 asection **input_list, **list;
2558 bfd_size_type amt;
2559 struct elf32_avr_link_hash_table *htab = avr_link_hash_table(info);
2560
2561 if (htab == NULL || htab->no_stubs)
2562 return 0;
2563
2564 /* Count the number of input BFDs and find the top input section id. */
2565 for (input_bfd = info->input_bfds, bfd_count = 0, top_id = 0;
2566 input_bfd != NULL;
2567 input_bfd = input_bfd->link_next)
2568 {
2569 bfd_count += 1;
2570 for (section = input_bfd->sections;
2571 section != NULL;
2572 section = section->next)
2573 if (top_id < section->id)
2574 top_id = section->id;
2575 }
2576
2577 htab->bfd_count = bfd_count;
2578
2579 /* We can't use output_bfd->section_count here to find the top output
2580 section index as some sections may have been removed, and
2581 strip_excluded_output_sections doesn't renumber the indices. */
2582 for (section = output_bfd->sections, top_index = 0;
2583 section != NULL;
2584 section = section->next)
2585 if (top_index < section->index)
2586 top_index = section->index;
2587
2588 htab->top_index = top_index;
2589 amt = sizeof (asection *) * (top_index + 1);
2590 input_list = bfd_malloc (amt);
2591 htab->input_list = input_list;
2592 if (input_list == NULL)
2593 return -1;
2594
2595 /* For sections we aren't interested in, mark their entries with a
2596 value we can check later. */
2597 list = input_list + top_index;
2598 do
2599 *list = bfd_abs_section_ptr;
2600 while (list-- != input_list);
2601
2602 for (section = output_bfd->sections;
2603 section != NULL;
2604 section = section->next)
2605 if ((section->flags & SEC_CODE) != 0)
2606 input_list[section->index] = NULL;
2607
2608 return 1;
2609 }
2610
2611
2612 /* Read in all local syms for all input bfds, and create hash entries
2613 for export stubs if we are building a multi-subspace shared lib.
2614 Returns -1 on error, 0 otherwise. */
2615
2616 static int
2617 get_local_syms (bfd *input_bfd, struct bfd_link_info *info)
2618 {
2619 unsigned int bfd_indx;
2620 Elf_Internal_Sym *local_syms, **all_local_syms;
2621 struct elf32_avr_link_hash_table *htab = avr_link_hash_table (info);
2622 bfd_size_type amt;
2623
2624 if (htab == NULL)
2625 return -1;
2626
2627 /* We want to read in symbol extension records only once. To do this
2628 we need to read in the local symbols in parallel and save them for
2629 later use; so hold pointers to the local symbols in an array. */
2630 amt = sizeof (Elf_Internal_Sym *) * htab->bfd_count;
2631 all_local_syms = bfd_zmalloc (amt);
2632 htab->all_local_syms = all_local_syms;
2633 if (all_local_syms == NULL)
2634 return -1;
2635
2636 /* Walk over all the input BFDs, swapping in local symbols.
2637 If we are creating a shared library, create hash entries for the
2638 export stubs. */
2639 for (bfd_indx = 0;
2640 input_bfd != NULL;
2641 input_bfd = input_bfd->link_next, bfd_indx++)
2642 {
2643 Elf_Internal_Shdr *symtab_hdr;
2644
2645 /* We'll need the symbol table in a second. */
2646 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2647 if (symtab_hdr->sh_info == 0)
2648 continue;
2649
2650 /* We need an array of the local symbols attached to the input bfd. */
2651 local_syms = (Elf_Internal_Sym *) symtab_hdr->contents;
2652 if (local_syms == NULL)
2653 {
2654 local_syms = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
2655 symtab_hdr->sh_info, 0,
2656 NULL, NULL, NULL);
2657 /* Cache them for elf_link_input_bfd. */
2658 symtab_hdr->contents = (unsigned char *) local_syms;
2659 }
2660 if (local_syms == NULL)
2661 return -1;
2662
2663 all_local_syms[bfd_indx] = local_syms;
2664 }
2665
2666 return 0;
2667 }
2668
2669 #define ADD_DUMMY_STUBS_FOR_DEBUGGING 0
2670
2671 bfd_boolean
2672 elf32_avr_size_stubs (bfd *output_bfd,
2673 struct bfd_link_info *info,
2674 bfd_boolean is_prealloc_run)
2675 {
2676 struct elf32_avr_link_hash_table *htab;
2677 int stub_changed = 0;
2678
2679 htab = avr_link_hash_table (info);
2680 if (htab == NULL)
2681 return FALSE;
2682
2683 /* At this point we initialize htab->vector_base
2684 To the start of the text output section. */
2685 htab->vector_base = htab->stub_sec->output_section->vma;
2686
2687 if (get_local_syms (info->input_bfds, info))
2688 {
2689 if (htab->all_local_syms)
2690 goto error_ret_free_local;
2691 return FALSE;
2692 }
2693
2694 if (ADD_DUMMY_STUBS_FOR_DEBUGGING)
2695 {
2696 struct elf32_avr_stub_hash_entry *test;
2697
2698 test = avr_add_stub ("Hugo",htab);
2699 test->target_value = 0x123456;
2700 test->stub_offset = 13;
2701
2702 test = avr_add_stub ("Hugo2",htab);
2703 test->target_value = 0x84210;
2704 test->stub_offset = 14;
2705 }
2706
2707 while (1)
2708 {
2709 bfd *input_bfd;
2710 unsigned int bfd_indx;
2711
2712 /* We will have to re-generate the stub hash table each time anything
2713 in memory has changed. */
2714
2715 bfd_hash_traverse (&htab->bstab, avr_mark_stub_not_to_be_necessary, htab);
2716 for (input_bfd = info->input_bfds, bfd_indx = 0;
2717 input_bfd != NULL;
2718 input_bfd = input_bfd->link_next, bfd_indx++)
2719 {
2720 Elf_Internal_Shdr *symtab_hdr;
2721 asection *section;
2722 Elf_Internal_Sym *local_syms;
2723
2724 /* We'll need the symbol table in a second. */
2725 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2726 if (symtab_hdr->sh_info == 0)
2727 continue;
2728
2729 local_syms = htab->all_local_syms[bfd_indx];
2730
2731 /* Walk over each section attached to the input bfd. */
2732 for (section = input_bfd->sections;
2733 section != NULL;
2734 section = section->next)
2735 {
2736 Elf_Internal_Rela *internal_relocs, *irelaend, *irela;
2737
2738 /* If there aren't any relocs, then there's nothing more
2739 to do. */
2740 if ((section->flags & SEC_RELOC) == 0
2741 || section->reloc_count == 0)
2742 continue;
2743
2744 /* If this section is a link-once section that will be
2745 discarded, then don't create any stubs. */
2746 if (section->output_section == NULL
2747 || section->output_section->owner != output_bfd)
2748 continue;
2749
2750 /* Get the relocs. */
2751 internal_relocs
2752 = _bfd_elf_link_read_relocs (input_bfd, section, NULL, NULL,
2753 info->keep_memory);
2754 if (internal_relocs == NULL)
2755 goto error_ret_free_local;
2756
2757 /* Now examine each relocation. */
2758 irela = internal_relocs;
2759 irelaend = irela + section->reloc_count;
2760 for (; irela < irelaend; irela++)
2761 {
2762 unsigned int r_type, r_indx;
2763 struct elf32_avr_stub_hash_entry *hsh;
2764 asection *sym_sec;
2765 bfd_vma sym_value;
2766 bfd_vma destination;
2767 struct elf_link_hash_entry *hh;
2768 char *stub_name;
2769
2770 r_type = ELF32_R_TYPE (irela->r_info);
2771 r_indx = ELF32_R_SYM (irela->r_info);
2772
2773 /* Only look for 16 bit GS relocs. No other reloc will need a
2774 stub. */
2775 if (!((r_type == R_AVR_16_PM)
2776 || (r_type == R_AVR_LO8_LDI_GS)
2777 || (r_type == R_AVR_HI8_LDI_GS)))
2778 continue;
2779
2780 /* Now determine the call target, its name, value,
2781 section. */
2782 sym_sec = NULL;
2783 sym_value = 0;
2784 destination = 0;
2785 hh = NULL;
2786 if (r_indx < symtab_hdr->sh_info)
2787 {
2788 /* It's a local symbol. */
2789 Elf_Internal_Sym *sym;
2790 Elf_Internal_Shdr *hdr;
2791 unsigned int shndx;
2792
2793 sym = local_syms + r_indx;
2794 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2795 sym_value = sym->st_value;
2796 shndx = sym->st_shndx;
2797 if (shndx < elf_numsections (input_bfd))
2798 {
2799 hdr = elf_elfsections (input_bfd)[shndx];
2800 sym_sec = hdr->bfd_section;
2801 destination = (sym_value + irela->r_addend
2802 + sym_sec->output_offset
2803 + sym_sec->output_section->vma);
2804 }
2805 }
2806 else
2807 {
2808 /* It's an external symbol. */
2809 int e_indx;
2810
2811 e_indx = r_indx - symtab_hdr->sh_info;
2812 hh = elf_sym_hashes (input_bfd)[e_indx];
2813
2814 while (hh->root.type == bfd_link_hash_indirect
2815 || hh->root.type == bfd_link_hash_warning)
2816 hh = (struct elf_link_hash_entry *)
2817 (hh->root.u.i.link);
2818
2819 if (hh->root.type == bfd_link_hash_defined
2820 || hh->root.type == bfd_link_hash_defweak)
2821 {
2822 sym_sec = hh->root.u.def.section;
2823 sym_value = hh->root.u.def.value;
2824 if (sym_sec->output_section != NULL)
2825 destination = (sym_value + irela->r_addend
2826 + sym_sec->output_offset
2827 + sym_sec->output_section->vma);
2828 }
2829 else if (hh->root.type == bfd_link_hash_undefweak)
2830 {
2831 if (! info->shared)
2832 continue;
2833 }
2834 else if (hh->root.type == bfd_link_hash_undefined)
2835 {
2836 if (! (info->unresolved_syms_in_objects == RM_IGNORE
2837 && (ELF_ST_VISIBILITY (hh->other)
2838 == STV_DEFAULT)))
2839 continue;
2840 }
2841 else
2842 {
2843 bfd_set_error (bfd_error_bad_value);
2844
2845 error_ret_free_internal:
2846 if (elf_section_data (section)->relocs == NULL)
2847 free (internal_relocs);
2848 goto error_ret_free_local;
2849 }
2850 }
2851
2852 if (! avr_stub_is_required_for_16_bit_reloc
2853 (destination - htab->vector_base))
2854 {
2855 if (!is_prealloc_run)
2856 /* We are having a reloc that does't need a stub. */
2857 continue;
2858
2859 /* We don't right now know if a stub will be needed.
2860 Let's rather be on the safe side. */
2861 }
2862
2863 /* Get the name of this stub. */
2864 stub_name = avr_stub_name (sym_sec, sym_value, irela);
2865
2866 if (!stub_name)
2867 goto error_ret_free_internal;
2868
2869
2870 hsh = avr_stub_hash_lookup (&htab->bstab,
2871 stub_name,
2872 FALSE, FALSE);
2873 if (hsh != NULL)
2874 {
2875 /* The proper stub has already been created. Mark it
2876 to be used and write the possibly changed destination
2877 value. */
2878 hsh->is_actually_needed = TRUE;
2879 hsh->target_value = destination;
2880 free (stub_name);
2881 continue;
2882 }
2883
2884 hsh = avr_add_stub (stub_name, htab);
2885 if (hsh == NULL)
2886 {
2887 free (stub_name);
2888 goto error_ret_free_internal;
2889 }
2890
2891 hsh->is_actually_needed = TRUE;
2892 hsh->target_value = destination;
2893
2894 if (debug_stubs)
2895 printf ("Adding stub with destination 0x%x to the"
2896 " hash table.\n", (unsigned int) destination);
2897 if (debug_stubs)
2898 printf ("(Pre-Alloc run: %i)\n", is_prealloc_run);
2899
2900 stub_changed = TRUE;
2901 }
2902
2903 /* We're done with the internal relocs, free them. */
2904 if (elf_section_data (section)->relocs == NULL)
2905 free (internal_relocs);
2906 }
2907 }
2908
2909 /* Re-Calculate the number of needed stubs. */
2910 htab->stub_sec->size = 0;
2911 bfd_hash_traverse (&htab->bstab, avr_size_one_stub, htab);
2912
2913 if (!stub_changed)
2914 break;
2915
2916 stub_changed = FALSE;
2917 }
2918
2919 free (htab->all_local_syms);
2920 return TRUE;
2921
2922 error_ret_free_local:
2923 free (htab->all_local_syms);
2924 return FALSE;
2925 }
2926
2927
2928 /* Build all the stubs associated with the current output file. The
2929 stubs are kept in a hash table attached to the main linker hash
2930 table. We also set up the .plt entries for statically linked PIC
2931 functions here. This function is called via hppaelf_finish in the
2932 linker. */
2933
2934 bfd_boolean
2935 elf32_avr_build_stubs (struct bfd_link_info *info)
2936 {
2937 asection *stub_sec;
2938 struct bfd_hash_table *table;
2939 struct elf32_avr_link_hash_table *htab;
2940 bfd_size_type total_size = 0;
2941
2942 htab = avr_link_hash_table (info);
2943 if (htab == NULL)
2944 return FALSE;
2945
2946 /* In case that there were several stub sections: */
2947 for (stub_sec = htab->stub_bfd->sections;
2948 stub_sec != NULL;
2949 stub_sec = stub_sec->next)
2950 {
2951 bfd_size_type size;
2952
2953 /* Allocate memory to hold the linker stubs. */
2954 size = stub_sec->size;
2955 total_size += size;
2956
2957 stub_sec->contents = bfd_zalloc (htab->stub_bfd, size);
2958 if (stub_sec->contents == NULL && size != 0)
2959 return FALSE;
2960 stub_sec->size = 0;
2961 }
2962
2963 /* Allocate memory for the adress mapping table. */
2964 htab->amt_entry_cnt = 0;
2965 htab->amt_max_entry_cnt = total_size / 4;
2966 htab->amt_stub_offsets = bfd_malloc (sizeof (bfd_vma)
2967 * htab->amt_max_entry_cnt);
2968 htab->amt_destination_addr = bfd_malloc (sizeof (bfd_vma)
2969 * htab->amt_max_entry_cnt );
2970
2971 if (debug_stubs)
2972 printf ("Allocating %i entries in the AMT\n", htab->amt_max_entry_cnt);
2973
2974 /* Build the stubs as directed by the stub hash table. */
2975 table = &htab->bstab;
2976 bfd_hash_traverse (table, avr_build_one_stub, info);
2977
2978 if (debug_stubs)
2979 printf ("Final Stub section Size: %i\n", (int) htab->stub_sec->size);
2980
2981 return TRUE;
2982 }
2983
2984 #define ELF_ARCH bfd_arch_avr
2985 #define ELF_MACHINE_CODE EM_AVR
2986 #define ELF_MACHINE_ALT1 EM_AVR_OLD
2987 #define ELF_MAXPAGESIZE 1
2988
2989 #define TARGET_LITTLE_SYM bfd_elf32_avr_vec
2990 #define TARGET_LITTLE_NAME "elf32-avr"
2991
2992 #define bfd_elf32_bfd_link_hash_table_create elf32_avr_link_hash_table_create
2993 #define bfd_elf32_bfd_link_hash_table_free elf32_avr_link_hash_table_free
2994
2995 #define elf_info_to_howto avr_info_to_howto_rela
2996 #define elf_info_to_howto_rel NULL
2997 #define elf_backend_relocate_section elf32_avr_relocate_section
2998 #define elf_backend_check_relocs elf32_avr_check_relocs
2999 #define elf_backend_can_gc_sections 1
3000 #define elf_backend_rela_normal 1
3001 #define elf_backend_final_write_processing \
3002 bfd_elf_avr_final_write_processing
3003 #define elf_backend_object_p elf32_avr_object_p
3004
3005 #define bfd_elf32_bfd_relax_section elf32_avr_relax_section
3006 #define bfd_elf32_bfd_get_relocated_section_contents \
3007 elf32_avr_get_relocated_section_contents
3008
3009 #include "elf32-target.h"
A mirror of the official binutils-gdb repository