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b6af0555 JS |
1 | /* Stack unwinding code based on dwarf2 frame info for GDB, the GNU debugger. |
2 | Copyright 2001 | |
3 | Free Software Foundation, Inc. | |
4 | Contributed by Jiri Smid, SuSE Labs. | |
5 | ||
6 | This file is part of GDB. | |
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 2 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., 59 Temple Place - Suite 330, | |
21 | Boston, MA 02111-1307, USA. */ | |
22 | ||
23 | #include "defs.h" | |
24 | #include "symtab.h" | |
25 | #include "symfile.h" | |
26 | #include "objfiles.h" | |
27 | #include "target.h" | |
28 | #include "elf/dwarf2.h" | |
29 | #include "inferior.h" | |
30 | #include "regcache.h" | |
31 | #include "dwarf2cfi.h" | |
32 | ||
33 | /* Common Information Entry - holds information that is shared among many | |
34 | Frame Descriptors. */ | |
35 | struct cie_unit | |
36 | { | |
37 | /* Offset of this unit in dwarf_frame_buffer. */ | |
38 | ULONGEST offset; | |
39 | ||
40 | /* A null-terminated string that identifies the augmentation to this CIE or | |
41 | to the FDEs that use it. */ | |
42 | char *augmentation; | |
43 | ||
44 | /* A constant that is factored out of all advance location instructions. */ | |
45 | unsigned int code_align; | |
46 | ||
47 | /* A constant that is factored out of all offset instructions. */ | |
48 | int data_align; | |
49 | ||
50 | /* A constant that indicates which regiter represents the return address | |
51 | of a function. */ | |
52 | unsigned char ra; | |
53 | ||
54 | /* Indicates how addresses are encoded. */ | |
55 | unsigned char addr_encoding; | |
56 | ||
57 | /* Pointer and length of the cie program. */ | |
58 | char *data; | |
59 | unsigned int data_length; | |
60 | ||
61 | struct objfile *objfile; | |
62 | ||
63 | /* Next in chain. */ | |
64 | struct cie_unit *next; | |
65 | }; | |
66 | ||
67 | /* Frame Description Entry. */ | |
68 | struct fde_unit | |
69 | { | |
70 | /* Address of the first location associated with this entry. */ | |
71 | CORE_ADDR initial_location; | |
72 | ||
73 | /* Length of program section described by this entry. */ | |
74 | CORE_ADDR address_range; | |
75 | ||
76 | /* Pointer to asociated CIE. */ | |
77 | struct cie_unit *cie_ptr; | |
78 | ||
79 | /* Pointer and length of the cie program. */ | |
80 | char *data; | |
81 | unsigned int data_length; | |
82 | }; | |
83 | ||
84 | struct fde_array | |
85 | { | |
86 | struct fde_unit **array; | |
87 | int elems; | |
88 | int array_size; | |
89 | }; | |
90 | ||
91 | struct context_reg | |
92 | { | |
93 | union | |
94 | { | |
95 | unsigned int reg; | |
96 | long offset; | |
97 | CORE_ADDR addr; | |
98 | } | |
99 | loc; | |
100 | enum | |
101 | { | |
102 | REG_CTX_UNSAVED, | |
103 | REG_CTX_SAVED_OFFSET, | |
104 | REG_CTX_SAVED_REG, | |
105 | REG_CTX_SAVED_ADDR, | |
106 | REG_CTX_VALUE, | |
107 | } | |
108 | how; | |
109 | }; | |
110 | ||
111 | /* This is the register and unwind state for a particular frame. */ | |
112 | struct context | |
113 | { | |
114 | struct context_reg *reg; | |
115 | ||
116 | CORE_ADDR cfa; | |
117 | CORE_ADDR ra; | |
118 | void *lsda; | |
119 | int args_size; | |
120 | }; | |
121 | ||
122 | struct frame_state_reg | |
123 | { | |
124 | union | |
125 | { | |
126 | unsigned int reg; | |
127 | long offset; | |
128 | unsigned char *exp; | |
129 | } | |
130 | loc; | |
131 | enum | |
132 | { | |
133 | REG_UNSAVED, | |
134 | REG_SAVED_OFFSET, | |
135 | REG_SAVED_REG, | |
136 | REG_SAVED_EXP, | |
137 | } | |
138 | how; | |
139 | }; | |
140 | ||
141 | struct frame_state | |
142 | { | |
143 | /* Each register save state can be described in terms of a CFA slot, | |
144 | another register, or a location expression. */ | |
145 | struct frame_state_regs | |
146 | { | |
147 | struct frame_state_reg *reg; | |
148 | ||
149 | /* Used to implement DW_CFA_remember_state. */ | |
150 | struct frame_state_regs *prev; | |
151 | } | |
152 | regs; | |
153 | ||
154 | /* The CFA can be described in terms of a reg+offset or a | |
155 | location expression. */ | |
156 | long cfa_offset; | |
157 | int cfa_reg; | |
158 | unsigned char *cfa_exp; | |
159 | enum | |
160 | { | |
161 | CFA_UNSET, | |
162 | CFA_REG_OFFSET, | |
163 | CFA_EXP, | |
164 | } | |
165 | cfa_how; | |
166 | ||
167 | /* The PC described by the current frame state. */ | |
168 | CORE_ADDR pc; | |
169 | ||
170 | /* The information we care about from the CIE/FDE. */ | |
171 | int data_align; | |
172 | unsigned int code_align; | |
173 | unsigned char retaddr_column; | |
174 | unsigned char addr_encoding; | |
175 | ||
176 | struct objfile *objfile; | |
177 | }; | |
178 | ||
179 | #define UNWIND_CONTEXT(fi) ((struct context *) (fi->context)) | |
180 | \f | |
181 | ||
182 | static struct cie_unit *cie_chunks; | |
183 | static struct fde_array fde_chunks; | |
184 | /* Obstack for allocating temporary storage used during unwind operations. */ | |
185 | static struct obstack unwind_tmp_obstack; | |
186 | ||
187 | extern file_ptr dwarf_frame_offset; | |
188 | extern unsigned int dwarf_frame_size; | |
189 | extern file_ptr dwarf_eh_frame_offset; | |
190 | extern unsigned int dwarf_eh_frame_size; | |
191 | ||
192 | static char *dwarf_frame_buffer; | |
193 | \f | |
194 | ||
195 | extern char *dwarf2_read_section (struct objfile *objfile, file_ptr offset, | |
196 | unsigned int size); | |
197 | ||
198 | static struct fde_unit *fde_unit_alloc (void); | |
199 | static struct cie_unit *cie_unit_alloc (void); | |
200 | static void fde_chunks_need_space (); | |
201 | ||
202 | static struct context *context_alloc (); | |
203 | static struct frame_state *frame_state_alloc (); | |
204 | static void unwind_tmp_obstack_free (); | |
205 | static void context_cpy (struct context *dst, struct context *src); | |
206 | ||
207 | static unsigned int read_1u (bfd *abfd, char **p); | |
208 | static int read_1s (bfd *abfd, char **p); | |
209 | static unsigned int read_2u (bfd *abfd, char **p); | |
210 | static int read_2s (bfd *abfd, char **p); | |
211 | static unsigned int read_4u (bfd *abfd, char **p); | |
212 | static int read_4s (bfd *abfd, char **p); | |
213 | static ULONGEST read_8u (bfd *abfd, char **p); | |
214 | static LONGEST read_8s (bfd *abfd, char **p); | |
215 | ||
216 | static ULONGEST read_uleb128 (bfd *abfd, char **p); | |
217 | static LONGEST read_sleb128 (bfd *abfd, char **p); | |
218 | static CORE_ADDR read_pointer (bfd *abfd, char **p); | |
219 | static CORE_ADDR read_encoded_pointer (bfd *abfd, char **p, | |
220 | unsigned char encoding); | |
221 | ||
222 | static LONGEST read_initial_length (bfd *abfd, char *buf, int *bytes_read); | |
223 | static ULONGEST read_length (bfd *abfd, char *buf, int *bytes_read, | |
224 | int dwarf64); | |
225 | static ULONGEST read_address (bfd *abfd, char **p); | |
226 | ||
227 | ||
228 | static int is_cie (ULONGEST cie_id, int dwarf64); | |
229 | static int compare_fde_unit (const void *a, const void *b); | |
230 | void dwarf2_build_frame_info (struct objfile *objfile); | |
231 | ||
232 | static void execute_cfa_program (struct objfile *objfile, char *insn_ptr, | |
233 | char *insn_end, struct context *context, | |
234 | struct frame_state *fs); | |
235 | static struct fde_unit *get_fde_for_addr (CORE_ADDR pc); | |
236 | static void frame_state_for (struct context *context, struct frame_state *fs); | |
237 | static void get_reg (char *reg, struct context *context, int regnum); | |
238 | static CORE_ADDR execute_stack_op (struct objfile *objfile, | |
239 | char *op_ptr, char *op_end, | |
240 | struct context *context, CORE_ADDR initial); | |
241 | static void update_context (struct context *context, struct frame_state *fs, | |
242 | int chain); | |
243 | ||
244 | \f | |
245 | /* Memory allocation functions. */ | |
246 | static struct fde_unit * | |
247 | fde_unit_alloc (void) | |
248 | { | |
249 | struct fde_unit *fde; | |
250 | ||
251 | fde = (struct fde_unit *) xmalloc (sizeof (struct fde_unit)); | |
252 | memset (fde, 0, sizeof (struct fde_unit)); | |
253 | return fde; | |
254 | } | |
255 | ||
256 | static struct cie_unit * | |
257 | cie_unit_alloc (void) | |
258 | { | |
259 | struct cie_unit *cie; | |
260 | ||
261 | cie = (struct cie_unit *) xmalloc (sizeof (struct cie_unit)); | |
262 | memset (cie, 0, sizeof (struct cie_unit)); | |
263 | return cie; | |
264 | } | |
265 | ||
266 | static void | |
267 | fde_chunks_need_space () | |
268 | { | |
269 | if (fde_chunks.elems < fde_chunks.array_size) | |
270 | return; | |
271 | fde_chunks.array_size = | |
272 | fde_chunks.array_size ? 2 * fde_chunks.array_size : 1024; | |
273 | fde_chunks.array = | |
274 | xrealloc (fde_chunks.array, | |
275 | sizeof (struct fde_unit) * fde_chunks.array_size); | |
276 | } | |
277 | ||
278 | /* Alocate a new `struct context' on temporary obstack. */ | |
279 | static struct context * | |
280 | context_alloc () | |
281 | { | |
282 | struct context *context; | |
283 | struct context_reg *reg; | |
284 | int regs_size = sizeof (struct context_reg) * NUM_REGS; | |
285 | ||
286 | context = (struct context *) obstack_alloc (&unwind_tmp_obstack, | |
287 | sizeof (struct context)); | |
288 | memset (context, 0, sizeof (struct context)); | |
289 | context->reg = (struct context_reg *) obstack_alloc (&unwind_tmp_obstack, | |
290 | regs_size); | |
291 | memset (context->reg, 0, regs_size); | |
292 | return context; | |
293 | } | |
294 | ||
295 | /* Alocate a new `struct frame_state' on temporary obstack. */ | |
296 | static struct frame_state * | |
297 | frame_state_alloc () | |
298 | { | |
299 | struct frame_state *fs; | |
300 | struct frame_state_reg *reg; | |
301 | int regs_size = sizeof (struct frame_state_reg) * NUM_REGS; | |
302 | ||
303 | fs = (struct frame_state *) obstack_alloc (&unwind_tmp_obstack, | |
304 | sizeof (struct frame_state)); | |
305 | memset (fs, 0, sizeof (struct frame_state)); | |
306 | fs->regs.reg = (struct frame_state_reg *) obstack_alloc (&unwind_tmp_obstack, | |
307 | regs_size); | |
308 | memset (fs->regs.reg, 0, regs_size); | |
309 | return fs; | |
310 | } | |
311 | ||
312 | static void | |
313 | unwind_tmp_obstack_free () | |
314 | { | |
315 | obstack_free (&unwind_tmp_obstack, NULL); | |
316 | obstack_init (&unwind_tmp_obstack); | |
317 | } | |
318 | ||
319 | static void | |
320 | context_cpy (struct context *dst, struct context *src) | |
321 | { | |
322 | struct context_reg *reg = dst->reg; | |
323 | int regs_size = sizeof (struct context_reg) * NUM_REGS; | |
324 | ||
325 | *dst = *src; | |
326 | memcpy (dst->reg, src->reg, regs_size); | |
327 | } | |
328 | \f | |
329 | ||
330 | static unsigned int | |
331 | read_1u (bfd *abfd, char **p) | |
332 | { | |
333 | unsigned ret; | |
334 | ||
335 | ret= bfd_get_8 (abfd, (bfd_byte *) *p); | |
336 | (*p) ++; | |
337 | return ret; | |
338 | } | |
339 | ||
340 | static int | |
341 | read_1s (bfd *abfd, char **p) | |
342 | { | |
343 | int ret; | |
344 | ||
345 | ret= bfd_get_signed_8 (abfd, (bfd_byte *) *p); | |
346 | (*p) ++; | |
347 | return ret; | |
348 | } | |
349 | ||
350 | static unsigned int | |
351 | read_2u (bfd *abfd, char **p) | |
352 | { | |
353 | unsigned ret; | |
354 | ||
355 | ret= bfd_get_16 (abfd, (bfd_byte *) *p); | |
356 | (*p) ++; | |
357 | return ret; | |
358 | } | |
359 | ||
360 | static int | |
361 | read_2s (bfd *abfd, char **p) | |
362 | { | |
363 | int ret; | |
364 | ||
365 | ret= bfd_get_signed_16 (abfd, (bfd_byte *) *p); | |
366 | (*p) += 2; | |
367 | return ret; | |
368 | } | |
369 | ||
370 | static unsigned int | |
371 | read_4u (bfd *abfd, char **p) | |
372 | { | |
373 | unsigned int ret; | |
374 | ||
375 | ret= bfd_get_32 (abfd, (bfd_byte *) *p); | |
376 | (*p) += 4; | |
377 | return ret; | |
378 | } | |
379 | ||
380 | static int | |
381 | read_4s (bfd *abfd, char **p) | |
382 | { | |
383 | int ret; | |
384 | ||
385 | ret= bfd_get_signed_32 (abfd, (bfd_byte *) *p); | |
386 | (*p) += 4; | |
387 | return ret; | |
388 | } | |
389 | ||
390 | static ULONGEST | |
391 | read_8u (bfd *abfd, char **p) | |
392 | { | |
393 | ULONGEST ret; | |
394 | ||
395 | ret = bfd_get_64 (abfd, (bfd_byte *) *p); | |
396 | (*p) += 8; | |
397 | return ret; | |
398 | } | |
399 | ||
400 | static LONGEST | |
401 | read_8s (bfd *abfd, char **p) | |
402 | { | |
403 | LONGEST ret; | |
404 | ||
405 | ret = bfd_get_signed_64 (abfd, (bfd_byte *) *p); | |
406 | (*p) += 8; | |
407 | return ret; | |
408 | } | |
409 | ||
410 | static ULONGEST | |
411 | read_uleb128 (bfd *abfd, char **p) | |
412 | { | |
413 | ULONGEST ret; | |
414 | int i, shift; | |
415 | unsigned char byte; | |
416 | ||
417 | ret = 0; | |
418 | shift = 0; | |
419 | i = 0; | |
420 | while (1) | |
421 | { | |
422 | byte = bfd_get_8 (abfd, (bfd_byte *) *p); | |
423 | (*p) ++; | |
424 | ret |= ((unsigned long) (byte & 127) << shift); | |
425 | if ((byte & 128) == 0) | |
426 | { | |
427 | break; | |
428 | } | |
429 | shift += 7; | |
430 | } | |
431 | return ret; | |
432 | } | |
433 | ||
434 | static LONGEST | |
435 | read_sleb128 (bfd *abfd, char **p) | |
436 | { | |
437 | LONGEST ret; | |
438 | int i, shift, size, num_read; | |
439 | unsigned char byte; | |
440 | ||
441 | ret = 0; | |
442 | shift = 0; | |
443 | size = 32; | |
444 | num_read = 0; | |
445 | i = 0; | |
446 | while (1) | |
447 | { | |
448 | byte = bfd_get_8 (abfd, (bfd_byte *) *p); | |
449 | (*p) ++; | |
450 | ret |= ((long) (byte & 127) << shift); | |
451 | shift += 7; | |
452 | if ((byte & 128) == 0) | |
453 | { | |
454 | break; | |
455 | } | |
456 | } | |
457 | if ((shift < size) && (byte & 0x40)) | |
458 | { | |
459 | ret |= -(1 << shift); | |
460 | } | |
461 | return ret; | |
462 | } | |
463 | ||
464 | static CORE_ADDR | |
465 | read_pointer (bfd *abfd, char **p) | |
466 | { | |
467 | switch (TARGET_ADDR_BIT / TARGET_CHAR_BIT) | |
468 | { | |
469 | case 4: | |
470 | return read_4u (abfd, p); | |
471 | case 8: | |
472 | return read_8u (abfd, p); | |
473 | default: | |
474 | error ("dwarf cfi error: unsupported target address length."); | |
475 | } | |
476 | } | |
477 | ||
478 | static CORE_ADDR | |
479 | read_encoded_pointer (bfd *abfd, char **p, unsigned char encoding) | |
480 | { | |
481 | CORE_ADDR ret; | |
482 | ||
483 | switch (encoding & 0x0f) | |
484 | { | |
485 | case DW_EH_PE_absptr: | |
486 | ret = read_pointer (abfd, p); | |
487 | break; | |
488 | ||
489 | case DW_EH_PE_uleb128: | |
490 | ret = read_uleb128 (abfd, p); | |
491 | break; | |
492 | case DW_EH_PE_sleb128: | |
493 | ret = read_sleb128 (abfd, p); | |
494 | break; | |
495 | ||
496 | case DW_EH_PE_udata2: | |
497 | ret = read_2u (abfd, p); | |
498 | break; | |
499 | case DW_EH_PE_udata4: | |
500 | ret = read_4u (abfd, p); | |
501 | break; | |
502 | case DW_EH_PE_udata8: | |
503 | ret = read_8u (abfd, p); | |
504 | break; | |
505 | ||
506 | case DW_EH_PE_sdata2: | |
507 | ret = read_2s (abfd, p); | |
508 | break; | |
509 | case DW_EH_PE_sdata4: | |
510 | ret = read_4s (abfd, p); | |
511 | break; | |
512 | case DW_EH_PE_sdata8: | |
513 | ret = read_8s (abfd, p); | |
514 | break; | |
515 | ||
516 | default: | |
517 | internal_error (__FILE__, __LINE__, | |
518 | "read_encoded_pointer: unknown pointer encoding"); | |
519 | } | |
520 | ||
521 | if (ret != 0) | |
522 | switch (encoding & 0xf0) | |
523 | { | |
524 | case DW_EH_PE_absptr: | |
525 | break; | |
526 | case DW_EH_PE_pcrel: | |
527 | ret += (CORE_ADDR) *p; | |
528 | break; | |
529 | case DW_EH_PE_textrel: | |
530 | case DW_EH_PE_datarel: | |
531 | case DW_EH_PE_funcrel: | |
532 | default: | |
533 | internal_error (__FILE__, __LINE__, | |
534 | "read_encoded_pointer: unknown pointer encoding"); | |
535 | } | |
536 | ||
537 | return ret; | |
538 | } | |
539 | ||
540 | static LONGEST | |
541 | read_initial_length (bfd * abfd, char *buf, int *bytes_read) | |
542 | { | |
543 | LONGEST ret = 0; | |
544 | ||
545 | ret = bfd_get_32 (abfd, (bfd_byte *) buf); | |
546 | ||
547 | if (ret == 0xffffffff) | |
548 | { | |
549 | ret = bfd_get_64 (abfd, (bfd_byte *) buf + 4); | |
550 | *bytes_read = 12; | |
551 | } | |
552 | else | |
553 | { | |
554 | *bytes_read = 4; | |
555 | } | |
556 | ||
557 | return ret; | |
558 | } | |
559 | ||
560 | static ULONGEST | |
561 | read_length (bfd * abfd, char *buf, int *bytes_read, int dwarf64) | |
562 | { | |
563 | if (dwarf64) | |
564 | { | |
565 | *bytes_read = 8; | |
566 | return read_8u (abfd, &buf); | |
567 | } | |
568 | else | |
569 | { | |
570 | *bytes_read = 4; | |
571 | return read_4u (abfd, &buf); | |
572 | } | |
573 | } | |
574 | ||
575 | static void | |
576 | execute_cfa_program ( struct objfile *objfile, char *insn_ptr, char *insn_end, | |
577 | struct context *context, struct frame_state *fs) | |
578 | { | |
579 | struct frame_state_regs *unused_rs = NULL; | |
580 | ||
581 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
582 | fs->regs.prev = NULL; | |
583 | ||
584 | while (insn_ptr < insn_end && fs->pc < context->ra) | |
585 | { | |
586 | unsigned char insn = *insn_ptr++; | |
587 | ULONGEST reg, uoffset; | |
588 | LONGEST offset; | |
589 | int bytes_read; | |
590 | ||
591 | if (insn & DW_CFA_advance_loc) | |
592 | fs->pc += (insn & 0x3f) * fs->code_align; | |
593 | else if (insn & DW_CFA_offset) | |
594 | { | |
595 | reg = insn & 0x3f; | |
596 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
597 | offset = (long) uoffset * fs->data_align; | |
598 | fs->regs.reg[reg].how = REG_SAVED_OFFSET; | |
599 | fs->regs.reg[reg].loc.offset = offset; | |
600 | } | |
601 | else if (insn & DW_CFA_restore) | |
602 | { | |
603 | reg = insn & 0x3f; | |
604 | fs->regs.reg[reg].how = REG_UNSAVED; | |
605 | } | |
606 | else | |
607 | switch (insn) | |
608 | { | |
609 | case DW_CFA_set_loc: | |
610 | fs->pc = read_encoded_pointer (objfile->obfd, &insn_ptr, | |
611 | fs->addr_encoding); | |
612 | break; | |
613 | ||
614 | case DW_CFA_advance_loc1: | |
615 | fs->pc += read_1u (objfile->obfd, &insn_ptr); | |
616 | break; | |
617 | case DW_CFA_advance_loc2: | |
618 | fs->pc += read_2u (objfile->obfd, &insn_ptr); | |
619 | break; | |
620 | case DW_CFA_advance_loc4: | |
621 | fs->pc += read_4u (objfile->obfd, &insn_ptr); | |
622 | break; | |
623 | ||
624 | case DW_CFA_offset_extended: | |
625 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
626 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
627 | offset = (long) uoffset *fs->data_align; | |
628 | fs->regs.reg[reg].how = REG_SAVED_OFFSET; | |
629 | fs->regs.reg[reg].loc.offset = offset; | |
630 | break; | |
631 | ||
632 | case DW_CFA_restore_extended: | |
633 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
634 | fs->regs.reg[reg].how = REG_UNSAVED; | |
635 | break; | |
636 | ||
637 | case DW_CFA_undefined: | |
638 | case DW_CFA_same_value: | |
639 | case DW_CFA_nop: | |
640 | break; | |
641 | ||
642 | case DW_CFA_register: | |
643 | { | |
644 | ULONGEST reg2; | |
645 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
646 | reg2 = read_uleb128 (objfile->obfd, &insn_ptr); | |
647 | fs->regs.reg[reg].how = REG_SAVED_REG; | |
648 | fs->regs.reg[reg].loc.reg = reg2; | |
649 | } | |
650 | break; | |
651 | ||
652 | case DW_CFA_remember_state: | |
653 | { | |
654 | struct frame_state_regs *new_rs; | |
655 | if (unused_rs) | |
656 | { | |
657 | new_rs = unused_rs; | |
658 | unused_rs = unused_rs->prev; | |
659 | } | |
660 | else | |
661 | new_rs = xmalloc (sizeof (struct frame_state_regs)); | |
662 | ||
663 | *new_rs = fs->regs; | |
664 | fs->regs.prev = new_rs; | |
665 | } | |
666 | break; | |
667 | ||
668 | case DW_CFA_restore_state: | |
669 | { | |
670 | struct frame_state_regs *old_rs = fs->regs.prev; | |
671 | fs->regs = *old_rs; | |
672 | old_rs->prev = unused_rs; | |
673 | unused_rs = old_rs; | |
674 | } | |
675 | break; | |
676 | ||
677 | case DW_CFA_def_cfa: | |
678 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
679 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
680 | fs->cfa_reg = reg; | |
681 | fs->cfa_offset = uoffset; | |
682 | fs->cfa_how = CFA_REG_OFFSET; | |
683 | break; | |
684 | ||
685 | case DW_CFA_def_cfa_register: | |
686 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
687 | fs->cfa_reg = reg; | |
688 | fs->cfa_how = CFA_REG_OFFSET; | |
689 | break; | |
690 | ||
691 | case DW_CFA_def_cfa_offset: | |
692 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
693 | fs->cfa_offset = uoffset; | |
694 | break; | |
695 | ||
696 | case DW_CFA_def_cfa_expression: | |
697 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
698 | fs->cfa_exp = insn_ptr; | |
699 | fs->cfa_how = CFA_EXP; | |
700 | insn_ptr += uoffset; | |
701 | break; | |
702 | ||
703 | case DW_CFA_expression: | |
704 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
705 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
706 | fs->regs.reg[reg].how = REG_SAVED_EXP; | |
707 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
708 | insn_ptr += uoffset; | |
709 | break; | |
710 | ||
711 | /* From the 2.1 draft. */ | |
712 | case DW_CFA_offset_extended_sf: | |
713 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
714 | offset = read_sleb128 (objfile->obfd, &insn_ptr); | |
715 | offset *= fs->data_align; | |
716 | fs->regs.reg[reg].how = REG_SAVED_OFFSET; | |
717 | fs->regs.reg[reg].loc.offset = offset; | |
718 | break; | |
719 | ||
720 | case DW_CFA_def_cfa_sf: | |
721 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
722 | offset = read_sleb128 (objfile->obfd, &insn_ptr); | |
723 | fs->cfa_offset = offset; | |
724 | fs->cfa_reg = reg; | |
725 | fs->cfa_how = CFA_REG_OFFSET; | |
726 | break; | |
727 | ||
728 | case DW_CFA_def_cfa_offset_sf: | |
729 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
730 | fs->cfa_offset = uoffset; | |
731 | /* cfa_how deliberately not set. */ | |
732 | break; | |
733 | ||
734 | case DW_CFA_GNU_window_save: | |
735 | /* ??? Hardcoded for SPARC register window configuration. */ | |
736 | for (reg = 16; reg < 32; ++reg) | |
737 | { | |
738 | fs->regs.reg[reg].how = REG_SAVED_OFFSET; | |
739 | fs->regs.reg[reg].loc.offset = (reg - 16) * sizeof (void *); | |
740 | } | |
741 | break; | |
742 | ||
743 | case DW_CFA_GNU_args_size: | |
744 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
745 | context->args_size = uoffset; | |
746 | break; | |
747 | ||
748 | case DW_CFA_GNU_negative_offset_extended: | |
749 | /* Obsoleted by DW_CFA_offset_extended_sf, but used by | |
750 | older PowerPC code. */ | |
751 | reg = read_uleb128 (objfile->obfd, &insn_ptr); | |
752 | uoffset = read_uleb128 (objfile->obfd, &insn_ptr); | |
753 | offset = (long) uoffset *fs->data_align; | |
754 | fs->regs.reg[reg].how = REG_SAVED_OFFSET; | |
755 | fs->regs.reg[reg].loc.offset = -offset; | |
756 | break; | |
757 | ||
758 | default: | |
759 | error ("dwarf cfi error: unknown cfa instruction %d.", insn); | |
760 | } | |
761 | } | |
762 | } | |
763 | ||
764 | static struct fde_unit * | |
765 | get_fde_for_addr (CORE_ADDR pc) | |
766 | { | |
767 | size_t lo, hi; | |
768 | struct fde_unit *fde = NULL; | |
769 | lo = 0; | |
770 | hi = fde_chunks.elems; | |
771 | ||
772 | while (lo < hi) | |
773 | { | |
774 | size_t i = (lo + hi) / 2; | |
775 | fde = fde_chunks.array[i]; | |
776 | if (pc < fde->initial_location) | |
777 | hi = i; | |
778 | else if (pc >= fde->initial_location + fde->address_range) | |
779 | lo = i + 1; | |
780 | else | |
781 | return fde; | |
782 | } | |
783 | return 0; | |
784 | } | |
785 | ||
786 | static void | |
787 | frame_state_for (struct context *context, struct frame_state *fs) | |
788 | { | |
789 | struct fde_unit *fde; | |
790 | struct cie_unit *cie; | |
791 | unsigned char *aug, *insn, *end; | |
792 | ||
793 | context->args_size = 0; | |
794 | context->lsda = 0; | |
795 | ||
796 | if ((fde = get_fde_for_addr (context->ra - 1)) != NULL) | |
797 | { | |
798 | fs->pc = fde->initial_location; | |
799 | ||
800 | cie = fde->cie_ptr; | |
801 | fs->code_align = cie->code_align; | |
802 | fs->data_align = cie->data_align; | |
803 | fs->retaddr_column = cie->ra; | |
804 | fs->addr_encoding = cie->addr_encoding; | |
805 | fs->objfile = cie->objfile; | |
806 | ||
807 | execute_cfa_program (cie->objfile, cie->data, | |
808 | cie->data + cie->data_length, context, fs); | |
809 | execute_cfa_program (cie->objfile, fde->data, | |
810 | fde->data + fde->data_length, context, fs); | |
811 | } | |
812 | } | |
813 | ||
814 | static void | |
815 | get_reg (char *reg, struct context *context, int regnum) | |
816 | { | |
817 | switch (context->reg[regnum].how) | |
818 | { | |
819 | case REG_CTX_UNSAVED: | |
820 | read_register_gen (regnum, reg); | |
821 | break; | |
822 | case REG_CTX_SAVED_OFFSET: | |
823 | target_read_memory (context->cfa + context->reg[regnum].loc.offset, | |
824 | reg, REGISTER_RAW_SIZE (regnum)); | |
825 | break; | |
826 | case REG_CTX_SAVED_REG: | |
827 | read_register_gen (context->reg[regnum].loc.reg, reg); | |
828 | break; | |
829 | case REG_CTX_SAVED_ADDR: | |
830 | target_read_memory (context->reg[regnum].loc.addr, | |
831 | reg, REGISTER_RAW_SIZE (regnum)); | |
832 | break; | |
833 | case REG_CTX_VALUE: | |
834 | memcpy (reg, &context->reg[regnum].loc.addr, | |
835 | REGISTER_RAW_SIZE (regnum)); | |
836 | break; | |
837 | default: | |
838 | internal_error (__FILE__, __LINE__, | |
839 | "get_reg: unknown register rule"); | |
840 | } | |
841 | } | |
842 | ||
843 | /* Decode a DW_OP stack program. Return the top of stack. Push INITIAL | |
844 | onto the stack to start. */ | |
845 | static CORE_ADDR | |
846 | execute_stack_op (struct objfile *objfile, | |
847 | char *op_ptr, char *op_end, struct context *context, | |
848 | CORE_ADDR initial) | |
849 | { | |
850 | CORE_ADDR stack[64]; /* ??? Assume this is enough. */ | |
851 | int stack_elt; | |
852 | ||
853 | stack[0] = initial; | |
854 | stack_elt = 1; | |
855 | ||
856 | while (op_ptr < op_end) | |
857 | { | |
858 | enum dwarf_location_atom op = *op_ptr++; | |
859 | ULONGEST result, reg; | |
860 | LONGEST offset; | |
861 | ||
862 | switch (op) | |
863 | { | |
864 | case DW_OP_lit0: | |
865 | case DW_OP_lit1: | |
866 | case DW_OP_lit2: | |
867 | case DW_OP_lit3: | |
868 | case DW_OP_lit4: | |
869 | case DW_OP_lit5: | |
870 | case DW_OP_lit6: | |
871 | case DW_OP_lit7: | |
872 | case DW_OP_lit8: | |
873 | case DW_OP_lit9: | |
874 | case DW_OP_lit10: | |
875 | case DW_OP_lit11: | |
876 | case DW_OP_lit12: | |
877 | case DW_OP_lit13: | |
878 | case DW_OP_lit14: | |
879 | case DW_OP_lit15: | |
880 | case DW_OP_lit16: | |
881 | case DW_OP_lit17: | |
882 | case DW_OP_lit18: | |
883 | case DW_OP_lit19: | |
884 | case DW_OP_lit20: | |
885 | case DW_OP_lit21: | |
886 | case DW_OP_lit22: | |
887 | case DW_OP_lit23: | |
888 | case DW_OP_lit24: | |
889 | case DW_OP_lit25: | |
890 | case DW_OP_lit26: | |
891 | case DW_OP_lit27: | |
892 | case DW_OP_lit28: | |
893 | case DW_OP_lit29: | |
894 | case DW_OP_lit30: | |
895 | case DW_OP_lit31: | |
896 | result = op - DW_OP_lit0; | |
897 | break; | |
898 | ||
899 | case DW_OP_addr: | |
900 | result = read_pointer (objfile->obfd, &op_ptr); | |
901 | break; | |
902 | ||
903 | case DW_OP_const1u: | |
904 | result = read_1u (objfile->obfd, &op_ptr); | |
905 | break; | |
906 | case DW_OP_const1s: | |
907 | result = read_1s (objfile->obfd, &op_ptr); | |
908 | break; | |
909 | case DW_OP_const2u: | |
910 | result = read_2u (objfile->obfd, &op_ptr); | |
911 | break; | |
912 | case DW_OP_const2s: | |
913 | result = read_2s (objfile->obfd, &op_ptr); | |
914 | break; | |
915 | case DW_OP_const4u: | |
916 | result = read_4u (objfile->obfd, &op_ptr); | |
917 | break; | |
918 | case DW_OP_const4s: | |
919 | result = read_4s (objfile->obfd, &op_ptr); | |
920 | break; | |
921 | case DW_OP_const8u: | |
922 | result = read_8u (objfile->obfd, &op_ptr); | |
923 | break; | |
924 | case DW_OP_const8s: | |
925 | result = read_8s (objfile->obfd, &op_ptr); | |
926 | break; | |
927 | case DW_OP_constu: | |
928 | result = read_uleb128 (objfile->obfd, &op_ptr); | |
929 | break; | |
930 | case DW_OP_consts: | |
931 | result = read_sleb128 (objfile->obfd, &op_ptr); | |
932 | break; | |
933 | ||
934 | case DW_OP_reg0: | |
935 | case DW_OP_reg1: | |
936 | case DW_OP_reg2: | |
937 | case DW_OP_reg3: | |
938 | case DW_OP_reg4: | |
939 | case DW_OP_reg5: | |
940 | case DW_OP_reg6: | |
941 | case DW_OP_reg7: | |
942 | case DW_OP_reg8: | |
943 | case DW_OP_reg9: | |
944 | case DW_OP_reg10: | |
945 | case DW_OP_reg11: | |
946 | case DW_OP_reg12: | |
947 | case DW_OP_reg13: | |
948 | case DW_OP_reg14: | |
949 | case DW_OP_reg15: | |
950 | case DW_OP_reg16: | |
951 | case DW_OP_reg17: | |
952 | case DW_OP_reg18: | |
953 | case DW_OP_reg19: | |
954 | case DW_OP_reg20: | |
955 | case DW_OP_reg21: | |
956 | case DW_OP_reg22: | |
957 | case DW_OP_reg23: | |
958 | case DW_OP_reg24: | |
959 | case DW_OP_reg25: | |
960 | case DW_OP_reg26: | |
961 | case DW_OP_reg27: | |
962 | case DW_OP_reg28: | |
963 | case DW_OP_reg29: | |
964 | case DW_OP_reg30: | |
965 | case DW_OP_reg31: | |
966 | get_reg ((char *) &result, context, op - DW_OP_reg0); | |
967 | break; | |
968 | case DW_OP_regx: | |
969 | reg = read_uleb128 (objfile->obfd, &op_ptr); | |
970 | get_reg ((char *) &result, context, reg); | |
971 | break; | |
972 | ||
973 | case DW_OP_breg0: | |
974 | case DW_OP_breg1: | |
975 | case DW_OP_breg2: | |
976 | case DW_OP_breg3: | |
977 | case DW_OP_breg4: | |
978 | case DW_OP_breg5: | |
979 | case DW_OP_breg6: | |
980 | case DW_OP_breg7: | |
981 | case DW_OP_breg8: | |
982 | case DW_OP_breg9: | |
983 | case DW_OP_breg10: | |
984 | case DW_OP_breg11: | |
985 | case DW_OP_breg12: | |
986 | case DW_OP_breg13: | |
987 | case DW_OP_breg14: | |
988 | case DW_OP_breg15: | |
989 | case DW_OP_breg16: | |
990 | case DW_OP_breg17: | |
991 | case DW_OP_breg18: | |
992 | case DW_OP_breg19: | |
993 | case DW_OP_breg20: | |
994 | case DW_OP_breg21: | |
995 | case DW_OP_breg22: | |
996 | case DW_OP_breg23: | |
997 | case DW_OP_breg24: | |
998 | case DW_OP_breg25: | |
999 | case DW_OP_breg26: | |
1000 | case DW_OP_breg27: | |
1001 | case DW_OP_breg28: | |
1002 | case DW_OP_breg29: | |
1003 | case DW_OP_breg30: | |
1004 | case DW_OP_breg31: | |
1005 | offset = read_sleb128 (objfile->obfd, &op_ptr); | |
1006 | get_reg ((char *) &result, context, op - DW_OP_breg0); | |
1007 | result += offset; | |
1008 | break; | |
1009 | case DW_OP_bregx: | |
1010 | reg = read_uleb128 (objfile->obfd, &op_ptr); | |
1011 | offset = read_sleb128 (objfile->obfd, &op_ptr); | |
1012 | get_reg ((char *) &result, context, reg); | |
1013 | result += offset; | |
1014 | break; | |
1015 | ||
1016 | case DW_OP_dup: | |
1017 | if (stack_elt < 1) | |
1018 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1019 | result = stack[stack_elt - 1]; | |
1020 | break; | |
1021 | ||
1022 | case DW_OP_drop: | |
1023 | if (--stack_elt < 0) | |
1024 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1025 | goto no_push; | |
1026 | ||
1027 | case DW_OP_pick: | |
1028 | offset = *op_ptr++; | |
1029 | if (offset >= stack_elt - 1) | |
1030 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1031 | result = stack[stack_elt - 1 - offset]; | |
1032 | break; | |
1033 | ||
1034 | case DW_OP_over: | |
1035 | if (stack_elt < 2) | |
1036 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1037 | result = stack[stack_elt - 2]; | |
1038 | break; | |
1039 | ||
1040 | case DW_OP_rot: | |
1041 | { | |
1042 | CORE_ADDR t1, t2, t3; | |
1043 | ||
1044 | if (stack_elt < 3) | |
1045 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1046 | t1 = stack[stack_elt - 1]; | |
1047 | t2 = stack[stack_elt - 2]; | |
1048 | t3 = stack[stack_elt - 3]; | |
1049 | stack[stack_elt - 1] = t2; | |
1050 | stack[stack_elt - 2] = t3; | |
1051 | stack[stack_elt - 3] = t1; | |
1052 | goto no_push; | |
1053 | } | |
1054 | ||
1055 | case DW_OP_deref: | |
1056 | case DW_OP_deref_size: | |
1057 | case DW_OP_abs: | |
1058 | case DW_OP_neg: | |
1059 | case DW_OP_not: | |
1060 | case DW_OP_plus_uconst: | |
1061 | /* Unary operations. */ | |
1062 | if (--stack_elt < 0) | |
1063 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1064 | result = stack[stack_elt]; | |
1065 | ||
1066 | switch (op) | |
1067 | { | |
1068 | case DW_OP_deref: | |
1069 | { | |
1070 | char *ptr = (char *) result; | |
1071 | result = read_pointer (objfile->obfd, &ptr); | |
1072 | } | |
1073 | break; | |
1074 | ||
1075 | case DW_OP_deref_size: | |
1076 | { | |
1077 | char *ptr = (char *) result; | |
1078 | switch (*op_ptr++) | |
1079 | { | |
1080 | case 1: | |
1081 | result = read_1u (objfile->obfd, &ptr); | |
1082 | break; | |
1083 | case 2: | |
1084 | result = read_2u (objfile->obfd, &ptr); | |
1085 | break; | |
1086 | case 4: | |
1087 | result = read_4u (objfile->obfd, &ptr); | |
1088 | break; | |
1089 | case 8: | |
1090 | result = read_8u (objfile->obfd, &ptr); | |
1091 | break; | |
1092 | default: | |
1093 | internal_error (__FILE__, __LINE__, | |
1094 | "execute_stack_op error"); | |
1095 | } | |
1096 | } | |
1097 | break; | |
1098 | ||
1099 | case DW_OP_abs: | |
1100 | if (result < 0) | |
1101 | result = -result; | |
1102 | break; | |
1103 | case DW_OP_neg: | |
1104 | result = -result; | |
1105 | break; | |
1106 | case DW_OP_not: | |
1107 | result = ~result; | |
1108 | break; | |
1109 | case DW_OP_plus_uconst: | |
1110 | result += read_uleb128 (objfile->obfd, &op_ptr); | |
1111 | break; | |
1112 | } | |
1113 | break; | |
1114 | ||
1115 | case DW_OP_and: | |
1116 | case DW_OP_div: | |
1117 | case DW_OP_minus: | |
1118 | case DW_OP_mod: | |
1119 | case DW_OP_mul: | |
1120 | case DW_OP_or: | |
1121 | case DW_OP_plus: | |
1122 | case DW_OP_le: | |
1123 | case DW_OP_ge: | |
1124 | case DW_OP_eq: | |
1125 | case DW_OP_lt: | |
1126 | case DW_OP_gt: | |
1127 | case DW_OP_ne: | |
1128 | { | |
1129 | /* Binary operations. */ | |
1130 | CORE_ADDR first, second; | |
1131 | if ((stack_elt -= 2) < 0) | |
1132 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1133 | second = stack[stack_elt]; | |
1134 | first = stack[stack_elt + 1]; | |
1135 | ||
1136 | switch (op) | |
1137 | { | |
1138 | case DW_OP_and: | |
1139 | result = second & first; | |
1140 | break; | |
1141 | case DW_OP_div: | |
1142 | result = (LONGEST) second / (LONGEST) first; | |
1143 | break; | |
1144 | case DW_OP_minus: | |
1145 | result = second - first; | |
1146 | break; | |
1147 | case DW_OP_mod: | |
1148 | result = (LONGEST) second % (LONGEST) first; | |
1149 | break; | |
1150 | case DW_OP_mul: | |
1151 | result = second * first; | |
1152 | break; | |
1153 | case DW_OP_or: | |
1154 | result = second | first; | |
1155 | break; | |
1156 | case DW_OP_plus: | |
1157 | result = second + first; | |
1158 | break; | |
1159 | case DW_OP_shl: | |
1160 | result = second << first; | |
1161 | break; | |
1162 | case DW_OP_shr: | |
1163 | result = second >> first; | |
1164 | break; | |
1165 | case DW_OP_shra: | |
1166 | result = (LONGEST) second >> first; | |
1167 | break; | |
1168 | case DW_OP_xor: | |
1169 | result = second ^ first; | |
1170 | break; | |
1171 | case DW_OP_le: | |
1172 | result = (LONGEST) first <= (LONGEST) second; | |
1173 | break; | |
1174 | case DW_OP_ge: | |
1175 | result = (LONGEST) first >= (LONGEST) second; | |
1176 | break; | |
1177 | case DW_OP_eq: | |
1178 | result = (LONGEST) first == (LONGEST) second; | |
1179 | break; | |
1180 | case DW_OP_lt: | |
1181 | result = (LONGEST) first < (LONGEST) second; | |
1182 | break; | |
1183 | case DW_OP_gt: | |
1184 | result = (LONGEST) first > (LONGEST) second; | |
1185 | break; | |
1186 | case DW_OP_ne: | |
1187 | result = (LONGEST) first != (LONGEST) second; | |
1188 | break; | |
1189 | } | |
1190 | } | |
1191 | break; | |
1192 | ||
1193 | case DW_OP_skip: | |
1194 | offset = read_2s (objfile->obfd, &op_ptr); | |
1195 | op_ptr += offset; | |
1196 | goto no_push; | |
1197 | ||
1198 | case DW_OP_bra: | |
1199 | if (--stack_elt < 0) | |
1200 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1201 | offset = read_2s (objfile->obfd, &op_ptr); | |
1202 | if (stack[stack_elt] != 0) | |
1203 | op_ptr += offset; | |
1204 | goto no_push; | |
1205 | ||
1206 | case DW_OP_nop: | |
1207 | goto no_push; | |
1208 | ||
1209 | default: | |
1210 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1211 | } | |
1212 | ||
1213 | /* Most things push a result value. */ | |
1214 | if ((size_t) stack_elt >= sizeof (stack) / sizeof (*stack)) | |
1215 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1216 | stack[++stack_elt] = result; | |
1217 | no_push:; | |
1218 | } | |
1219 | ||
1220 | /* We were executing this program to get a value. It should be | |
1221 | at top of stack. */ | |
1222 | if (--stack_elt < 0) | |
1223 | internal_error (__FILE__, __LINE__, "execute_stack_op error"); | |
1224 | return stack[stack_elt]; | |
1225 | } | |
1226 | ||
1227 | static void | |
1228 | update_context (struct context *context, struct frame_state *fs, int chain) | |
1229 | { | |
1230 | struct context *orig_context; | |
1231 | CORE_ADDR cfa; | |
1232 | long i; | |
1233 | ||
1234 | orig_context = context_alloc (); | |
1235 | context_cpy (orig_context, context); | |
1236 | /* Compute this frame's CFA. */ | |
1237 | switch (fs->cfa_how) | |
1238 | { | |
1239 | case CFA_REG_OFFSET: | |
1240 | get_reg ((char *) &cfa, context, fs->cfa_reg); | |
1241 | cfa += fs->cfa_offset; | |
1242 | break; | |
1243 | ||
1244 | case CFA_EXP: | |
1245 | /* ??? No way of knowing what register number is the stack pointer | |
1246 | to do the same sort of handling as above. Assume that if the | |
1247 | CFA calculation is so complicated as to require a stack program | |
1248 | that this will not be a problem. */ | |
1249 | { | |
1250 | char *exp = fs->cfa_exp; | |
1251 | ULONGEST len; | |
1252 | ||
1253 | len = read_uleb128 (fs->objfile->obfd, &exp); | |
1254 | cfa = (CORE_ADDR) execute_stack_op (fs->objfile, exp, | |
1255 | exp + len, context, 0); | |
1256 | break; | |
1257 | } | |
1258 | } | |
1259 | context->cfa = cfa; | |
1260 | ||
1261 | if (!chain) | |
1262 | orig_context->cfa = cfa; | |
1263 | ||
1264 | /* Compute the addresses of all registers saved in this frame. */ | |
1265 | for (i = 0; i < NUM_REGS; ++i) | |
1266 | switch (fs->regs.reg[i].how) | |
1267 | { | |
1268 | case REG_UNSAVED: | |
1269 | if (i == SP_REGNUM) | |
1270 | { | |
1271 | context->reg[i].how = REG_CTX_VALUE; | |
1272 | context->reg[i].loc.addr = cfa; | |
1273 | } | |
1274 | else | |
1275 | context->reg[i].how = REG_CTX_UNSAVED; | |
1276 | break; | |
1277 | case REG_SAVED_OFFSET: | |
1278 | context->reg[i].how = REG_CTX_SAVED_OFFSET; | |
1279 | context->reg[i].loc.offset = fs->regs.reg[i].loc.offset; | |
1280 | break; | |
1281 | case REG_SAVED_REG: | |
1282 | switch (orig_context->reg[fs->regs.reg[i].loc.reg].how) | |
1283 | { | |
1284 | case REG_CTX_UNSAVED: | |
1285 | context->reg[i].how = REG_CTX_UNSAVED; | |
1286 | break; | |
1287 | case REG_CTX_SAVED_OFFSET: | |
1288 | context->reg[i].how = REG_CTX_SAVED_OFFSET; | |
1289 | context->reg[i].loc.offset = orig_context->cfa - context->cfa + | |
1290 | orig_context->reg[fs->regs.reg[i].loc.reg].loc.offset; | |
1291 | break; | |
1292 | case REG_CTX_SAVED_REG: | |
1293 | context->reg[i].how = REG_CTX_SAVED_REG; | |
1294 | context->reg[i].loc.reg = | |
1295 | orig_context->reg[fs->regs.reg[i].loc.reg].loc.reg; | |
1296 | break; | |
1297 | case REG_CTX_SAVED_ADDR: | |
1298 | context->reg[i].how = REG_CTX_SAVED_ADDR; | |
1299 | context->reg[i].loc.addr = | |
1300 | orig_context->reg[fs->regs.reg[i].loc.reg].loc.addr; | |
1301 | default: | |
1302 | internal_error (__FILE__, __LINE__, | |
1303 | "cfi_update_context: unknown register rule"); | |
1304 | } | |
1305 | break; | |
1306 | case REG_SAVED_EXP: | |
1307 | { | |
1308 | char *exp = fs->regs.reg[i].loc.exp; | |
1309 | ULONGEST len; | |
1310 | CORE_ADDR val; | |
1311 | ||
1312 | len = read_uleb128 (fs->objfile->obfd, &exp); | |
1313 | val = execute_stack_op (fs->objfile, exp, exp + len, | |
1314 | orig_context, cfa); | |
1315 | context->reg[i].how = REG_CTX_SAVED_ADDR; | |
1316 | context->reg[i].loc.addr = val; | |
1317 | } | |
1318 | break; | |
1319 | default: | |
1320 | internal_error (__FILE__, __LINE__, | |
1321 | "cfi_update_context: unknown register rule"); | |
1322 | ||
1323 | } | |
1324 | get_reg ((char *) &context->ra, context, fs->retaddr_column); | |
1325 | unwind_tmp_obstack_free (); | |
1326 | } | |
1327 | ||
1328 | static int | |
1329 | is_cie (ULONGEST cie_id, int dwarf64) | |
1330 | { | |
1331 | return dwarf64 ? (cie_id == 0xffffffffffffffff) : (cie_id == 0xffffffff); | |
1332 | } | |
1333 | ||
1334 | static int | |
1335 | compare_fde_unit (const void *a, const void *b) | |
1336 | { | |
1337 | struct fde_unit **first, **second; | |
1338 | first = (struct fde_unit **) a; | |
1339 | second = (struct fde_unit **) b; | |
1340 | if ((*first)->initial_location > (*second)->initial_location) | |
1341 | return 1; | |
1342 | else if ((*first)->initial_location < (*second)->initial_location) | |
1343 | return -1; | |
1344 | else | |
1345 | return 0; | |
1346 | } | |
1347 | ||
1348 | /* Build the cie_chunks and fde_chunks tables from informations | |
1349 | in .debug.frame section. */ | |
1350 | void | |
1351 | dwarf2_build_frame_info (struct objfile *objfile) | |
1352 | { | |
1353 | bfd *abfd = objfile->obfd; | |
1354 | char *start = NULL; | |
1355 | char *end = NULL; | |
1356 | ||
1357 | obstack_init (&unwind_tmp_obstack); | |
1358 | ||
1359 | dwarf_frame_buffer = 0; | |
1360 | ||
1361 | if (dwarf_frame_offset) | |
1362 | { | |
1363 | dwarf_frame_buffer = dwarf2_read_section (objfile, | |
1364 | dwarf_frame_offset, | |
1365 | dwarf_frame_size); | |
1366 | ||
1367 | start = dwarf_frame_buffer; | |
1368 | end = dwarf_frame_buffer + dwarf_frame_size; | |
1369 | } | |
1370 | else if (dwarf_eh_frame_offset) | |
1371 | { | |
1372 | dwarf_frame_buffer = dwarf2_read_section (objfile, | |
1373 | dwarf_eh_frame_offset, | |
1374 | dwarf_eh_frame_size); | |
1375 | ||
1376 | start = dwarf_frame_buffer; | |
1377 | end = dwarf_frame_buffer + dwarf_eh_frame_size; | |
1378 | } | |
1379 | ||
1380 | if (start) | |
1381 | { | |
1382 | while (start < end) | |
1383 | { | |
1384 | unsigned long length; | |
1385 | ULONGEST cie_id; | |
1386 | ULONGEST unit_offset = start - dwarf_frame_buffer; | |
1387 | int bytes_read; | |
1388 | int dwarf64; | |
1389 | char *block_end; | |
1390 | ||
1391 | length = read_initial_length (abfd, start, &bytes_read); | |
1392 | start += bytes_read; | |
1393 | dwarf64 = (bytes_read == 12); | |
1394 | block_end = start + length; | |
1395 | ||
1396 | cie_id = read_length (abfd, start, &bytes_read, dwarf64); | |
1397 | start += bytes_read; | |
1398 | ||
1399 | if (is_cie (cie_id, dwarf64)) | |
1400 | { | |
1401 | struct cie_unit *cie = cie_unit_alloc (); | |
1402 | char *aug; | |
1403 | ||
1404 | cie->objfile = objfile; | |
1405 | cie->next = cie_chunks; | |
1406 | cie_chunks = cie; | |
1407 | ||
1408 | cie->objfile = objfile; | |
1409 | ||
1410 | cie->offset = unit_offset; | |
1411 | ||
1412 | start++; /* version */ | |
1413 | ||
1414 | cie->augmentation = aug = start; | |
1415 | while (*start) | |
1416 | start++; | |
1417 | start++; /* skip past NUL */ | |
1418 | ||
1419 | cie->code_align = read_uleb128 (abfd, &start); | |
1420 | cie->data_align = read_sleb128 (abfd, &start); | |
1421 | cie->ra = read_1u (abfd, &start); | |
1422 | ||
1423 | if (*aug == 'z') | |
1424 | { | |
1425 | int xtra = read_uleb128 (abfd, &start); | |
1426 | start += xtra; | |
1427 | ++aug; | |
1428 | } | |
1429 | ||
1430 | while (*aug != '\0') | |
1431 | { | |
1432 | if (aug[0] == 'e' && aug[1] == 'h') | |
1433 | { | |
1434 | start += sizeof (void *); | |
1435 | aug += 2; | |
1436 | } | |
1437 | else if (aug[0] == 'R') | |
1438 | { | |
1439 | cie->addr_encoding = *start++; | |
1440 | aug += 1; | |
1441 | } | |
1442 | else if (aug[0] == 'P') | |
1443 | { | |
1444 | CORE_ADDR ptr; | |
1445 | ptr = read_encoded_pointer (abfd, &start, | |
1446 | cie->addr_encoding); | |
1447 | aug += 1; | |
1448 | } | |
1449 | else | |
1450 | warning ("unknown augmentation"); | |
1451 | } | |
1452 | ||
1453 | cie->data = start; | |
1454 | cie->data_length = block_end - start; | |
1455 | } | |
1456 | else | |
1457 | { | |
1458 | struct fde_unit *fde; | |
1459 | struct cie_unit *cie; | |
1460 | ||
1461 | fde_chunks_need_space (); | |
1462 | fde = fde_unit_alloc (); | |
1463 | ||
1464 | fde_chunks.array[fde_chunks.elems++] = fde; | |
1465 | fde->initial_location = read_pointer (abfd, &start); | |
1466 | fde->address_range = read_pointer (abfd, &start); | |
1467 | ||
1468 | for (cie = cie_chunks; | |
1469 | cie && (cie->offset != cie_id); cie = cie->next); | |
1470 | if (!cie) | |
1471 | error ("dwarf cfi error: can't find CIE pointer"); | |
1472 | fde->cie_ptr = cie; | |
1473 | ||
1474 | if (cie->augmentation[0] == 'z') | |
1475 | read_uleb128 (abfd, &start); | |
1476 | ||
1477 | fde->data = start; | |
1478 | fde->data_length = block_end - start; | |
1479 | } | |
1480 | start = block_end; | |
1481 | } | |
1482 | qsort (fde_chunks.array, fde_chunks.elems, | |
1483 | sizeof (struct fde_unit *), compare_fde_unit); | |
1484 | } | |
1485 | } | |
1486 | \f | |
1487 | ||
1488 | /* Return the frame address. */ | |
1489 | CORE_ADDR | |
1490 | cfi_read_fp () | |
1491 | { | |
1492 | struct context *context; | |
1493 | struct frame_state *fs; | |
1494 | CORE_ADDR cfa; | |
1495 | ||
1496 | context = context_alloc (); | |
1497 | fs = frame_state_alloc (); | |
1498 | ||
1499 | context->ra = read_pc () + 1; | |
1500 | ||
1501 | frame_state_for (context, fs); | |
1502 | update_context (context, fs, 0); | |
1503 | ||
1504 | cfa = context->cfa; | |
1505 | unwind_tmp_obstack_free (); | |
1506 | return cfa; | |
1507 | } | |
1508 | ||
1509 | /* Store the frame address. */ | |
1510 | void | |
1511 | cfi_write_fp (CORE_ADDR val) | |
1512 | { | |
1513 | struct context *context; | |
1514 | struct frame_state *fs; | |
1515 | ||
1516 | context = context_alloc (); | |
1517 | fs = frame_state_alloc (); | |
1518 | ||
1519 | context->ra = read_pc () + 1; | |
1520 | ||
1521 | frame_state_for (context, fs); | |
1522 | ||
1523 | if (fs->cfa_how == CFA_REG_OFFSET) | |
1524 | { | |
1525 | val -= fs->cfa_offset; | |
1526 | write_register_gen (fs->cfa_reg, (char *) &val); | |
1527 | } | |
1528 | else | |
1529 | warning ("Can't write fp."); | |
1530 | ||
1531 | unwind_tmp_obstack_free (); | |
1532 | } | |
1533 | ||
1534 | /* Restore the machine to the state it had before the current frame | |
1535 | was created. */ | |
1536 | void | |
1537 | cfi_pop_frame (struct frame_info *fi) | |
1538 | { | |
1539 | char regbuf[MAX_REGISTER_RAW_SIZE]; | |
1540 | int regnum; | |
1541 | ||
1542 | fi = get_current_frame (); | |
1543 | ||
1544 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
1545 | { | |
1546 | get_reg (regbuf, UNWIND_CONTEXT (fi), regnum); | |
1547 | write_register_bytes (REGISTER_BYTE (regnum), regbuf, | |
1548 | REGISTER_RAW_SIZE (regnum)); | |
1549 | } | |
1550 | write_register (PC_REGNUM, UNWIND_CONTEXT (fi)->ra); | |
1551 | ||
1552 | flush_cached_frames (); | |
1553 | } | |
1554 | ||
1555 | /* Determine the address of the calling function's frame. */ | |
1556 | CORE_ADDR | |
1557 | cfi_frame_chain (struct frame_info *fi) | |
1558 | { | |
1559 | struct context *context; | |
1560 | struct frame_state *fs; | |
1561 | CORE_ADDR cfa; | |
1562 | ||
1563 | context = context_alloc (); | |
1564 | fs = frame_state_alloc (); | |
1565 | context_cpy (context, UNWIND_CONTEXT (fi)); | |
1566 | ||
1567 | /* outermost frame */ | |
1568 | if (context->ra == 0) | |
1569 | { | |
1570 | unwind_tmp_obstack_free (); | |
1571 | return 0; | |
1572 | } | |
1573 | ||
1574 | frame_state_for (context, fs); | |
1575 | update_context (context, fs, 1); | |
1576 | ||
1577 | cfa = context->cfa; | |
1578 | unwind_tmp_obstack_free (); | |
1579 | return cfa; | |
1580 | } | |
1581 | ||
1582 | /* Sets the pc of the frame. */ | |
1583 | void | |
1584 | cfi_init_frame_pc (int fromleaf, struct frame_info *fi) | |
1585 | { | |
1586 | if (fi->next) | |
1587 | get_reg ((char *) &(fi->pc), UNWIND_CONTEXT (fi->next), PC_REGNUM); | |
1588 | else | |
1589 | fi->pc = read_pc (); | |
1590 | } | |
1591 | ||
1592 | /* Initialize unwind context informations of the frame. */ | |
1593 | void | |
1594 | cfi_init_extra_frame_info (int fromleaf, struct frame_info *fi) | |
1595 | { | |
1596 | struct frame_state *fs; | |
1597 | ||
1598 | fs = frame_state_alloc (); | |
1599 | fi->context = frame_obstack_alloc (sizeof (struct context)); | |
1600 | UNWIND_CONTEXT (fi)->reg = | |
1601 | frame_obstack_alloc (sizeof (struct context_reg) * NUM_REGS); | |
1602 | memset (UNWIND_CONTEXT (fi)->reg, 0, | |
1603 | sizeof (struct context_reg) * NUM_REGS); | |
1604 | ||
1605 | if (fi->next) | |
1606 | { | |
1607 | context_cpy (UNWIND_CONTEXT (fi), UNWIND_CONTEXT (fi->next)); | |
1608 | frame_state_for (UNWIND_CONTEXT (fi), fs); | |
1609 | update_context (UNWIND_CONTEXT (fi), fs, 1); | |
1610 | } | |
1611 | else | |
1612 | { | |
1613 | UNWIND_CONTEXT (fi)->ra = fi->pc + 1; | |
1614 | frame_state_for (UNWIND_CONTEXT (fi), fs); | |
1615 | update_context (UNWIND_CONTEXT (fi), fs, 0); | |
1616 | } | |
1617 | unwind_tmp_obstack_free (); | |
1618 | } | |
1619 | ||
1620 | /* Obtain return address of the frame. */ | |
1621 | CORE_ADDR | |
1622 | cfi_get_ra (struct frame_info *fi) | |
1623 | { | |
1624 | return UNWIND_CONTEXT (fi)->ra; | |
1625 | } | |
1626 | ||
1627 | /* Find register number REGNUM relative to FRAME and put its | |
1628 | (raw) contents in *RAW_BUFFER. Set *OPTIMIZED if the variable | |
1629 | was optimized out (and thus can't be fetched). If the variable | |
1630 | was fetched from memory, set *ADDRP to where it was fetched from, | |
1631 | otherwise it was fetched from a register. | |
1632 | ||
1633 | The argument RAW_BUFFER must point to aligned memory. */ | |
1634 | void | |
1635 | cfi_get_saved_register (char *raw_buffer, | |
1636 | int *optimized, | |
1637 | CORE_ADDR * addrp, | |
1638 | struct frame_info *frame, | |
1639 | int regnum, enum lval_type *lval) | |
1640 | { | |
1641 | if (!target_has_registers) | |
1642 | error ("No registers."); | |
1643 | ||
1644 | /* Normal systems don't optimize out things with register numbers. */ | |
1645 | if (optimized != NULL) | |
1646 | *optimized = 0; | |
1647 | ||
1648 | if (addrp) /* default assumption: not found in memory */ | |
1649 | *addrp = 0; | |
1650 | ||
1651 | if (!frame->next) | |
1652 | { | |
1653 | read_register_gen (regnum, raw_buffer); | |
1654 | if (lval != NULL) | |
1655 | *lval = lval_register; | |
1656 | if (addrp != NULL) | |
1657 | *addrp = REGISTER_BYTE (regnum); | |
1658 | } | |
1659 | else | |
1660 | { | |
1661 | frame = frame->next; | |
1662 | switch (UNWIND_CONTEXT (frame)->reg[regnum].how) | |
1663 | { | |
1664 | case REG_CTX_UNSAVED: | |
1665 | read_register_gen (regnum, raw_buffer); | |
1666 | if (lval != NULL) | |
1667 | *lval = not_lval; | |
1668 | if (optimized != NULL) | |
1669 | *optimized = 1; | |
1670 | break; | |
1671 | case REG_CTX_SAVED_OFFSET: | |
1672 | target_read_memory (UNWIND_CONTEXT (frame)->cfa + | |
1673 | UNWIND_CONTEXT (frame)->reg[regnum].loc.offset, | |
1674 | raw_buffer, REGISTER_RAW_SIZE (regnum)); | |
1675 | if (lval != NULL) | |
1676 | *lval = lval_memory; | |
1677 | if (addrp != NULL) | |
1678 | *addrp = | |
1679 | UNWIND_CONTEXT (frame)->cfa + | |
1680 | UNWIND_CONTEXT (frame)->reg[regnum].loc.offset; | |
1681 | break; | |
1682 | case REG_CTX_SAVED_REG: | |
1683 | read_register_gen (UNWIND_CONTEXT (frame)->reg[regnum].loc.reg, | |
1684 | raw_buffer); | |
1685 | if (lval != NULL) | |
1686 | *lval = lval_register; | |
1687 | if (addrp != NULL) | |
1688 | *addrp = | |
1689 | REGISTER_BYTE (UNWIND_CONTEXT (frame)->reg[regnum].loc.reg); | |
1690 | break; | |
1691 | case REG_CTX_SAVED_ADDR: | |
1692 | target_read_memory (UNWIND_CONTEXT (frame)->reg[regnum].loc.addr, | |
1693 | raw_buffer, REGISTER_RAW_SIZE (regnum)); | |
1694 | if (lval != NULL) | |
1695 | *lval = lval_memory; | |
1696 | if (addrp != NULL) | |
1697 | *addrp = UNWIND_CONTEXT (frame)->reg[regnum].loc.addr; | |
1698 | break; | |
1699 | case REG_CTX_VALUE: | |
1700 | memcpy (raw_buffer, &UNWIND_CONTEXT (frame)->reg[regnum].loc.addr, | |
1701 | REGISTER_RAW_SIZE (regnum)); | |
1702 | if (lval != NULL) | |
1703 | *lval = not_lval; | |
1704 | if (optimized != NULL) | |
1705 | *optimized = 0; | |
1706 | break; | |
1707 | default: | |
1708 | internal_error (__FILE__, __LINE__, | |
1709 | "cfi_get_saved_register: unknown register rule"); | |
1710 | } | |
1711 | } | |
1712 | } | |
1713 | ||
1714 | /* Return the register that the function uses for a frame pointer, | |
1715 | plus any necessary offset to be applied to the register before | |
1716 | any frame pointer offsets. */ | |
1717 | void | |
1718 | cfi_virtual_frame_pointer (CORE_ADDR pc, int *frame_reg, | |
1719 | LONGEST * frame_offset) | |
1720 | { | |
1721 | struct context *context; | |
1722 | struct frame_state *fs; | |
1723 | ||
1724 | context = context_alloc (); | |
1725 | fs = frame_state_alloc (); | |
1726 | ||
1727 | context->ra = read_pc () + 1; | |
1728 | ||
1729 | frame_state_for (context, fs); | |
1730 | ||
1731 | if (fs->cfa_how == CFA_REG_OFFSET) | |
1732 | { | |
1733 | *frame_reg = fs->cfa_reg; | |
1734 | *frame_offset = fs->cfa_offset; | |
1735 | } | |
1736 | else | |
1737 | error ("dwarf cfi error: CFA is not defined as CFA_REG_OFFSET"); | |
1738 | ||
1739 | unwind_tmp_obstack_free (); | |
1740 | } |