Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
6aba47ca | 3 | Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc. |
cfc14b3a MK |
4 | |
5 | Contributed by Mark Kettenis. | |
6 | ||
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
cfc14b3a MK |
12 | (at your option) any later version. |
13 | ||
14 | This program is distributed in the hope that it will be useful, | |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
cfc14b3a MK |
21 | |
22 | #include "defs.h" | |
23 | #include "dwarf2expr.h" | |
24 | #include "elf/dwarf2.h" | |
25 | #include "frame.h" | |
26 | #include "frame-base.h" | |
27 | #include "frame-unwind.h" | |
28 | #include "gdbcore.h" | |
29 | #include "gdbtypes.h" | |
30 | #include "symtab.h" | |
31 | #include "objfiles.h" | |
32 | #include "regcache.h" | |
f2da6b3a | 33 | #include "value.h" |
cfc14b3a MK |
34 | |
35 | #include "gdb_assert.h" | |
36 | #include "gdb_string.h" | |
37 | ||
6896c0c7 | 38 | #include "complaints.h" |
cfc14b3a MK |
39 | #include "dwarf2-frame.h" |
40 | ||
41 | /* Call Frame Information (CFI). */ | |
42 | ||
43 | /* Common Information Entry (CIE). */ | |
44 | ||
45 | struct dwarf2_cie | |
46 | { | |
47 | /* Offset into the .debug_frame section where this CIE was found. | |
48 | Used to identify this CIE. */ | |
49 | ULONGEST cie_pointer; | |
50 | ||
51 | /* Constant that is factored out of all advance location | |
52 | instructions. */ | |
53 | ULONGEST code_alignment_factor; | |
54 | ||
55 | /* Constants that is factored out of all offset instructions. */ | |
56 | LONGEST data_alignment_factor; | |
57 | ||
58 | /* Return address column. */ | |
59 | ULONGEST return_address_register; | |
60 | ||
61 | /* Instruction sequence to initialize a register set. */ | |
852483bc MK |
62 | gdb_byte *initial_instructions; |
63 | gdb_byte *end; | |
cfc14b3a | 64 | |
303b6f5d DJ |
65 | /* Saved augmentation, in case it's needed later. */ |
66 | char *augmentation; | |
67 | ||
cfc14b3a | 68 | /* Encoding of addresses. */ |
852483bc | 69 | gdb_byte encoding; |
cfc14b3a | 70 | |
7131cb6e RH |
71 | /* True if a 'z' augmentation existed. */ |
72 | unsigned char saw_z_augmentation; | |
73 | ||
56c987f6 AO |
74 | /* True if an 'S' augmentation existed. */ |
75 | unsigned char signal_frame; | |
76 | ||
303b6f5d DJ |
77 | /* The version recorded in the CIE. */ |
78 | unsigned char version; | |
79 | ||
cfc14b3a MK |
80 | struct dwarf2_cie *next; |
81 | }; | |
82 | ||
83 | /* Frame Description Entry (FDE). */ | |
84 | ||
85 | struct dwarf2_fde | |
86 | { | |
87 | /* CIE for this FDE. */ | |
88 | struct dwarf2_cie *cie; | |
89 | ||
90 | /* First location associated with this FDE. */ | |
91 | CORE_ADDR initial_location; | |
92 | ||
93 | /* Number of bytes of program instructions described by this FDE. */ | |
94 | CORE_ADDR address_range; | |
95 | ||
96 | /* Instruction sequence. */ | |
852483bc MK |
97 | gdb_byte *instructions; |
98 | gdb_byte *end; | |
cfc14b3a | 99 | |
4bf8967c AS |
100 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
101 | section. */ | |
102 | unsigned char eh_frame_p; | |
103 | ||
cfc14b3a MK |
104 | struct dwarf2_fde *next; |
105 | }; | |
106 | ||
107 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc); | |
4fc771b8 DJ |
108 | |
109 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
110 | int eh_frame_p); | |
cfc14b3a MK |
111 | \f |
112 | ||
113 | /* Structure describing a frame state. */ | |
114 | ||
115 | struct dwarf2_frame_state | |
116 | { | |
117 | /* Each register save state can be described in terms of a CFA slot, | |
118 | another register, or a location expression. */ | |
119 | struct dwarf2_frame_state_reg_info | |
120 | { | |
05cbe71a | 121 | struct dwarf2_frame_state_reg *reg; |
cfc14b3a MK |
122 | int num_regs; |
123 | ||
124 | /* Used to implement DW_CFA_remember_state. */ | |
125 | struct dwarf2_frame_state_reg_info *prev; | |
126 | } regs; | |
127 | ||
128 | LONGEST cfa_offset; | |
129 | ULONGEST cfa_reg; | |
852483bc | 130 | gdb_byte *cfa_exp; |
cfc14b3a MK |
131 | enum { |
132 | CFA_UNSET, | |
133 | CFA_REG_OFFSET, | |
134 | CFA_EXP | |
135 | } cfa_how; | |
136 | ||
137 | /* The PC described by the current frame state. */ | |
138 | CORE_ADDR pc; | |
139 | ||
140 | /* Initial register set from the CIE. | |
141 | Used to implement DW_CFA_restore. */ | |
142 | struct dwarf2_frame_state_reg_info initial; | |
143 | ||
144 | /* The information we care about from the CIE. */ | |
145 | LONGEST data_align; | |
146 | ULONGEST code_align; | |
147 | ULONGEST retaddr_column; | |
303b6f5d DJ |
148 | |
149 | /* Flags for known producer quirks. */ | |
150 | ||
151 | /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa | |
152 | and DW_CFA_def_cfa_offset takes a factored offset. */ | |
153 | int armcc_cfa_offsets_sf; | |
154 | ||
155 | /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that | |
156 | the CFA is defined as REG - OFFSET rather than REG + OFFSET. */ | |
157 | int armcc_cfa_offsets_reversed; | |
cfc14b3a MK |
158 | }; |
159 | ||
160 | /* Store the length the expression for the CFA in the `cfa_reg' field, | |
161 | which is unused in that case. */ | |
162 | #define cfa_exp_len cfa_reg | |
163 | ||
f57d151a | 164 | /* Assert that the register set RS is large enough to store gdbarch_num_regs |
cfc14b3a MK |
165 | columns. If necessary, enlarge the register set. */ |
166 | ||
167 | static void | |
168 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, | |
169 | int num_regs) | |
170 | { | |
171 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
172 | ||
173 | if (num_regs <= rs->num_regs) | |
174 | return; | |
175 | ||
176 | rs->reg = (struct dwarf2_frame_state_reg *) | |
177 | xrealloc (rs->reg, num_regs * size); | |
178 | ||
179 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 180 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
181 | rs->num_regs = num_regs; |
182 | } | |
183 | ||
184 | /* Copy the register columns in register set RS into newly allocated | |
185 | memory and return a pointer to this newly created copy. */ | |
186 | ||
187 | static struct dwarf2_frame_state_reg * | |
188 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
189 | { | |
d10891d4 | 190 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
191 | struct dwarf2_frame_state_reg *reg; |
192 | ||
193 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
194 | memcpy (reg, rs->reg, size); | |
195 | ||
196 | return reg; | |
197 | } | |
198 | ||
199 | /* Release the memory allocated to register set RS. */ | |
200 | ||
201 | static void | |
202 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
203 | { | |
204 | if (rs) | |
205 | { | |
206 | dwarf2_frame_state_free_regs (rs->prev); | |
207 | ||
208 | xfree (rs->reg); | |
209 | xfree (rs); | |
210 | } | |
211 | } | |
212 | ||
213 | /* Release the memory allocated to the frame state FS. */ | |
214 | ||
215 | static void | |
216 | dwarf2_frame_state_free (void *p) | |
217 | { | |
218 | struct dwarf2_frame_state *fs = p; | |
219 | ||
220 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
221 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
222 | xfree (fs->initial.reg); | |
223 | xfree (fs->regs.reg); | |
224 | xfree (fs); | |
225 | } | |
226 | \f | |
227 | ||
228 | /* Helper functions for execute_stack_op. */ | |
229 | ||
230 | static CORE_ADDR | |
231 | read_reg (void *baton, int reg) | |
232 | { | |
233 | struct frame_info *next_frame = (struct frame_info *) baton; | |
05cbe71a | 234 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a | 235 | int regnum; |
852483bc | 236 | gdb_byte *buf; |
cfc14b3a | 237 | |
055d23b8 | 238 | regnum = gdbarch_dwarf2_reg_to_regnum (current_gdbarch, reg); |
cfc14b3a | 239 | |
852483bc | 240 | buf = alloca (register_size (gdbarch, regnum)); |
cfc14b3a | 241 | frame_unwind_register (next_frame, regnum, buf); |
f2da6b3a DJ |
242 | |
243 | /* Convert the register to an integer. This returns a LONGEST | |
244 | rather than a CORE_ADDR, but unpack_pointer does the same thing | |
245 | under the covers, and this makes more sense for non-pointer | |
246 | registers. Maybe read_reg and the associated interfaces should | |
247 | deal with "struct value" instead of CORE_ADDR. */ | |
248 | return unpack_long (register_type (gdbarch, regnum), buf); | |
cfc14b3a MK |
249 | } |
250 | ||
251 | static void | |
852483bc | 252 | read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
cfc14b3a MK |
253 | { |
254 | read_memory (addr, buf, len); | |
255 | } | |
256 | ||
257 | static void | |
852483bc | 258 | no_get_frame_base (void *baton, gdb_byte **start, size_t *length) |
cfc14b3a MK |
259 | { |
260 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 261 | _("Support for DW_OP_fbreg is unimplemented")); |
cfc14b3a MK |
262 | } |
263 | ||
264 | static CORE_ADDR | |
265 | no_get_tls_address (void *baton, CORE_ADDR offset) | |
266 | { | |
267 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 268 | _("Support for DW_OP_GNU_push_tls_address is unimplemented")); |
cfc14b3a MK |
269 | } |
270 | ||
271 | static CORE_ADDR | |
852483bc | 272 | execute_stack_op (gdb_byte *exp, ULONGEST len, |
cfc14b3a MK |
273 | struct frame_info *next_frame, CORE_ADDR initial) |
274 | { | |
275 | struct dwarf_expr_context *ctx; | |
276 | CORE_ADDR result; | |
277 | ||
278 | ctx = new_dwarf_expr_context (); | |
279 | ctx->baton = next_frame; | |
280 | ctx->read_reg = read_reg; | |
281 | ctx->read_mem = read_mem; | |
282 | ctx->get_frame_base = no_get_frame_base; | |
283 | ctx->get_tls_address = no_get_tls_address; | |
284 | ||
285 | dwarf_expr_push (ctx, initial); | |
286 | dwarf_expr_eval (ctx, exp, len); | |
287 | result = dwarf_expr_fetch (ctx, 0); | |
288 | ||
289 | if (ctx->in_reg) | |
290 | result = read_reg (next_frame, result); | |
291 | ||
292 | free_dwarf_expr_context (ctx); | |
293 | ||
294 | return result; | |
295 | } | |
296 | \f | |
297 | ||
298 | static void | |
852483bc | 299 | execute_cfa_program (gdb_byte *insn_ptr, gdb_byte *insn_end, |
cfc14b3a | 300 | struct frame_info *next_frame, |
4bf8967c | 301 | struct dwarf2_frame_state *fs, int eh_frame_p) |
cfc14b3a MK |
302 | { |
303 | CORE_ADDR pc = frame_pc_unwind (next_frame); | |
304 | int bytes_read; | |
4bf8967c | 305 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a MK |
306 | |
307 | while (insn_ptr < insn_end && fs->pc <= pc) | |
308 | { | |
852483bc | 309 | gdb_byte insn = *insn_ptr++; |
cfc14b3a MK |
310 | ULONGEST utmp, reg; |
311 | LONGEST offset; | |
312 | ||
313 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
314 | fs->pc += (insn & 0x3f) * fs->code_align; | |
315 | else if ((insn & 0xc0) == DW_CFA_offset) | |
316 | { | |
317 | reg = insn & 0x3f; | |
4fc771b8 | 318 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
319 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
320 | offset = utmp * fs->data_align; | |
321 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 322 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
323 | fs->regs.reg[reg].loc.offset = offset; |
324 | } | |
325 | else if ((insn & 0xc0) == DW_CFA_restore) | |
326 | { | |
327 | gdb_assert (fs->initial.reg); | |
328 | reg = insn & 0x3f; | |
4fc771b8 | 329 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 330 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
92ad9f6b FR |
331 | if (reg < fs->initial.num_regs) |
332 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
333 | else | |
334 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
335 | ||
336 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
337 | complaint (&symfile_complaints, _("\ | |
338 | incomplete CFI data; DW_CFA_restore unspecified\n\ | |
339 | register %s (#%d) at 0x%s"), | |
c9f4d572 | 340 | gdbarch_register_name |
055d23b8 UW |
341 | (current_gdbarch, gdbarch_dwarf2_reg_to_regnum |
342 | (current_gdbarch, reg)), | |
343 | gdbarch_dwarf2_reg_to_regnum (current_gdbarch, reg), | |
344 | paddr (fs->pc)); | |
cfc14b3a MK |
345 | } |
346 | else | |
347 | { | |
348 | switch (insn) | |
349 | { | |
350 | case DW_CFA_set_loc: | |
351 | fs->pc = dwarf2_read_address (insn_ptr, insn_end, &bytes_read); | |
352 | insn_ptr += bytes_read; | |
353 | break; | |
354 | ||
355 | case DW_CFA_advance_loc1: | |
356 | utmp = extract_unsigned_integer (insn_ptr, 1); | |
357 | fs->pc += utmp * fs->code_align; | |
358 | insn_ptr++; | |
359 | break; | |
360 | case DW_CFA_advance_loc2: | |
361 | utmp = extract_unsigned_integer (insn_ptr, 2); | |
362 | fs->pc += utmp * fs->code_align; | |
363 | insn_ptr += 2; | |
364 | break; | |
365 | case DW_CFA_advance_loc4: | |
366 | utmp = extract_unsigned_integer (insn_ptr, 4); | |
367 | fs->pc += utmp * fs->code_align; | |
368 | insn_ptr += 4; | |
369 | break; | |
370 | ||
371 | case DW_CFA_offset_extended: | |
372 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 373 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
374 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
375 | offset = utmp * fs->data_align; | |
376 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 377 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
378 | fs->regs.reg[reg].loc.offset = offset; |
379 | break; | |
380 | ||
381 | case DW_CFA_restore_extended: | |
382 | gdb_assert (fs->initial.reg); | |
383 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 384 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
385 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
386 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
387 | break; | |
388 | ||
389 | case DW_CFA_undefined: | |
390 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 391 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 392 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 393 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
394 | break; |
395 | ||
396 | case DW_CFA_same_value: | |
397 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 398 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 399 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 400 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
401 | break; |
402 | ||
403 | case DW_CFA_register: | |
404 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 405 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 406 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 407 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 408 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 409 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
410 | fs->regs.reg[reg].loc.reg = utmp; |
411 | break; | |
412 | ||
413 | case DW_CFA_remember_state: | |
414 | { | |
415 | struct dwarf2_frame_state_reg_info *new_rs; | |
416 | ||
417 | new_rs = XMALLOC (struct dwarf2_frame_state_reg_info); | |
418 | *new_rs = fs->regs; | |
419 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
420 | fs->regs.prev = new_rs; | |
421 | } | |
422 | break; | |
423 | ||
424 | case DW_CFA_restore_state: | |
425 | { | |
426 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
427 | ||
50ea7769 MK |
428 | if (old_rs == NULL) |
429 | { | |
e2e0b3e5 AC |
430 | complaint (&symfile_complaints, _("\ |
431 | bad CFI data; mismatched DW_CFA_restore_state at 0x%s"), paddr (fs->pc)); | |
50ea7769 MK |
432 | } |
433 | else | |
434 | { | |
435 | xfree (fs->regs.reg); | |
436 | fs->regs = *old_rs; | |
437 | xfree (old_rs); | |
438 | } | |
cfc14b3a MK |
439 | } |
440 | break; | |
441 | ||
442 | case DW_CFA_def_cfa: | |
443 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
444 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
445 | |
446 | if (fs->armcc_cfa_offsets_sf) | |
447 | utmp *= fs->data_align; | |
448 | ||
cfc14b3a MK |
449 | fs->cfa_offset = utmp; |
450 | fs->cfa_how = CFA_REG_OFFSET; | |
451 | break; | |
452 | ||
453 | case DW_CFA_def_cfa_register: | |
454 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
455 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
456 | eh_frame_p); | |
cfc14b3a MK |
457 | fs->cfa_how = CFA_REG_OFFSET; |
458 | break; | |
459 | ||
460 | case DW_CFA_def_cfa_offset: | |
852483bc | 461 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
462 | |
463 | if (fs->armcc_cfa_offsets_sf) | |
464 | utmp *= fs->data_align; | |
465 | ||
852483bc | 466 | fs->cfa_offset = utmp; |
cfc14b3a MK |
467 | /* cfa_how deliberately not set. */ |
468 | break; | |
469 | ||
a8504492 MK |
470 | case DW_CFA_nop: |
471 | break; | |
472 | ||
cfc14b3a MK |
473 | case DW_CFA_def_cfa_expression: |
474 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_exp_len); | |
475 | fs->cfa_exp = insn_ptr; | |
476 | fs->cfa_how = CFA_EXP; | |
477 | insn_ptr += fs->cfa_exp_len; | |
478 | break; | |
479 | ||
480 | case DW_CFA_expression: | |
481 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 482 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
483 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
484 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
485 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
486 | fs->regs.reg[reg].exp_len = utmp; | |
05cbe71a | 487 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
488 | insn_ptr += utmp; |
489 | break; | |
490 | ||
a8504492 MK |
491 | case DW_CFA_offset_extended_sf: |
492 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 493 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
a8504492 | 494 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 495 | offset *= fs->data_align; |
a8504492 | 496 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 497 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
498 | fs->regs.reg[reg].loc.offset = offset; |
499 | break; | |
500 | ||
46ea248b AO |
501 | case DW_CFA_val_offset: |
502 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
503 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
504 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
505 | offset = utmp * fs->data_align; | |
506 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
507 | fs->regs.reg[reg].loc.offset = offset; | |
508 | break; | |
509 | ||
510 | case DW_CFA_val_offset_sf: | |
511 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
512 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
513 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
514 | offset *= fs->data_align; | |
515 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
516 | fs->regs.reg[reg].loc.offset = offset; | |
517 | break; | |
518 | ||
519 | case DW_CFA_val_expression: | |
520 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
521 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
522 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
523 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
524 | fs->regs.reg[reg].exp_len = utmp; | |
525 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; | |
526 | insn_ptr += utmp; | |
527 | break; | |
528 | ||
a8504492 MK |
529 | case DW_CFA_def_cfa_sf: |
530 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
531 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
532 | eh_frame_p); | |
a8504492 MK |
533 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
534 | fs->cfa_offset = offset * fs->data_align; | |
535 | fs->cfa_how = CFA_REG_OFFSET; | |
536 | break; | |
537 | ||
538 | case DW_CFA_def_cfa_offset_sf: | |
539 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
540 | fs->cfa_offset = offset * fs->data_align; | |
541 | /* cfa_how deliberately not set. */ | |
cfc14b3a MK |
542 | break; |
543 | ||
a77f4086 MK |
544 | case DW_CFA_GNU_window_save: |
545 | /* This is SPARC-specific code, and contains hard-coded | |
546 | constants for the register numbering scheme used by | |
547 | GCC. Rather than having a architecture-specific | |
548 | operation that's only ever used by a single | |
549 | architecture, we provide the implementation here. | |
550 | Incidentally that's what GCC does too in its | |
551 | unwinder. */ | |
552 | { | |
553 | struct gdbarch *gdbarch = get_frame_arch (next_frame); | |
554 | int size = register_size(gdbarch, 0); | |
555 | dwarf2_frame_state_alloc_regs (&fs->regs, 32); | |
556 | for (reg = 8; reg < 16; reg++) | |
557 | { | |
558 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; | |
559 | fs->regs.reg[reg].loc.reg = reg + 16; | |
560 | } | |
561 | for (reg = 16; reg < 32; reg++) | |
562 | { | |
563 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
564 | fs->regs.reg[reg].loc.offset = (reg - 16) * size; | |
565 | } | |
566 | } | |
567 | break; | |
568 | ||
cfc14b3a MK |
569 | case DW_CFA_GNU_args_size: |
570 | /* Ignored. */ | |
571 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
572 | break; | |
573 | ||
58894217 JK |
574 | case DW_CFA_GNU_negative_offset_extended: |
575 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 576 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
58894217 JK |
577 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset); |
578 | offset *= fs->data_align; | |
579 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
580 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
581 | fs->regs.reg[reg].loc.offset = -offset; | |
582 | break; | |
583 | ||
cfc14b3a | 584 | default: |
e2e0b3e5 | 585 | internal_error (__FILE__, __LINE__, _("Unknown CFI encountered.")); |
cfc14b3a MK |
586 | } |
587 | } | |
588 | } | |
589 | ||
590 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
591 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
592 | fs->regs.prev = NULL; | |
593 | } | |
8f22cb90 | 594 | \f |
cfc14b3a | 595 | |
8f22cb90 | 596 | /* Architecture-specific operations. */ |
cfc14b3a | 597 | |
8f22cb90 MK |
598 | /* Per-architecture data key. */ |
599 | static struct gdbarch_data *dwarf2_frame_data; | |
600 | ||
601 | struct dwarf2_frame_ops | |
602 | { | |
603 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
604 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
605 | struct frame_info *); | |
3ed09a32 DJ |
606 | |
607 | /* Check whether the frame preceding NEXT_FRAME will be a signal | |
608 | trampoline. */ | |
609 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); | |
4bf8967c | 610 | |
4fc771b8 DJ |
611 | /* Convert .eh_frame register number to DWARF register number, or |
612 | adjust .debug_frame register number. */ | |
613 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
614 | }; |
615 | ||
8f22cb90 MK |
616 | /* Default architecture-specific register state initialization |
617 | function. */ | |
618 | ||
619 | static void | |
620 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 DM |
621 | struct dwarf2_frame_state_reg *reg, |
622 | struct frame_info *next_frame) | |
8f22cb90 MK |
623 | { |
624 | /* If we have a register that acts as a program counter, mark it as | |
625 | a destination for the return address. If we have a register that | |
626 | serves as the stack pointer, arrange for it to be filled with the | |
627 | call frame address (CFA). The other registers are marked as | |
628 | unspecified. | |
629 | ||
630 | We copy the return address to the program counter, since many | |
631 | parts in GDB assume that it is possible to get the return address | |
632 | by unwinding the program counter register. However, on ISA's | |
633 | with a dedicated return address register, the CFI usually only | |
634 | contains information to unwind that return address register. | |
635 | ||
636 | The reason we're treating the stack pointer special here is | |
637 | because in many cases GCC doesn't emit CFI for the stack pointer | |
638 | and implicitly assumes that it is equal to the CFA. This makes | |
639 | some sense since the DWARF specification (version 3, draft 8, | |
640 | p. 102) says that: | |
641 | ||
642 | "Typically, the CFA is defined to be the value of the stack | |
643 | pointer at the call site in the previous frame (which may be | |
644 | different from its value on entry to the current frame)." | |
645 | ||
646 | However, this isn't true for all platforms supported by GCC | |
647 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
648 | their own architecture-specific initialization function. */ | |
05cbe71a | 649 | |
3e8c568d | 650 | if (regnum == gdbarch_pc_regnum (current_gdbarch)) |
8f22cb90 | 651 | reg->how = DWARF2_FRAME_REG_RA; |
3e8c568d | 652 | else if (regnum == gdbarch_sp_regnum (current_gdbarch)) |
8f22cb90 MK |
653 | reg->how = DWARF2_FRAME_REG_CFA; |
654 | } | |
05cbe71a | 655 | |
8f22cb90 | 656 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 657 | |
8f22cb90 | 658 | static void * |
030f20e1 | 659 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
660 | { |
661 | struct dwarf2_frame_ops *ops; | |
662 | ||
030f20e1 | 663 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
664 | ops->init_reg = dwarf2_frame_default_init_reg; |
665 | return ops; | |
666 | } | |
05cbe71a | 667 | |
8f22cb90 MK |
668 | /* Set the architecture-specific register state initialization |
669 | function for GDBARCH to INIT_REG. */ | |
670 | ||
671 | void | |
672 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
673 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
674 | struct dwarf2_frame_state_reg *, |
675 | struct frame_info *)) | |
8f22cb90 | 676 | { |
030f20e1 | 677 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 678 | |
8f22cb90 MK |
679 | ops->init_reg = init_reg; |
680 | } | |
681 | ||
682 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
683 | |
684 | static void | |
685 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 DM |
686 | struct dwarf2_frame_state_reg *reg, |
687 | struct frame_info *next_frame) | |
05cbe71a | 688 | { |
030f20e1 | 689 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 690 | |
aff37fc1 | 691 | ops->init_reg (gdbarch, regnum, reg, next_frame); |
05cbe71a | 692 | } |
3ed09a32 DJ |
693 | |
694 | /* Set the architecture-specific signal trampoline recognition | |
695 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
696 | ||
697 | void | |
698 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
699 | int (*signal_frame_p) (struct gdbarch *, | |
700 | struct frame_info *)) | |
701 | { | |
702 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
703 | ||
704 | ops->signal_frame_p = signal_frame_p; | |
705 | } | |
706 | ||
707 | /* Query the architecture-specific signal frame recognizer for | |
708 | NEXT_FRAME. */ | |
709 | ||
710 | static int | |
711 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
712 | struct frame_info *next_frame) | |
713 | { | |
714 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
715 | ||
716 | if (ops->signal_frame_p == NULL) | |
717 | return 0; | |
718 | return ops->signal_frame_p (gdbarch, next_frame); | |
719 | } | |
4bf8967c | 720 | |
4fc771b8 DJ |
721 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
722 | register numbers. */ | |
4bf8967c AS |
723 | |
724 | void | |
4fc771b8 DJ |
725 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
726 | int (*adjust_regnum) (struct gdbarch *, | |
727 | int, int)) | |
4bf8967c AS |
728 | { |
729 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
730 | ||
4fc771b8 | 731 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
732 | } |
733 | ||
4fc771b8 DJ |
734 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
735 | register. */ | |
4bf8967c | 736 | |
4fc771b8 DJ |
737 | static int |
738 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p) | |
4bf8967c AS |
739 | { |
740 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
741 | ||
4fc771b8 | 742 | if (ops->adjust_regnum == NULL) |
4bf8967c | 743 | return regnum; |
4fc771b8 | 744 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 745 | } |
303b6f5d DJ |
746 | |
747 | static void | |
748 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
749 | struct dwarf2_fde *fde) | |
750 | { | |
751 | static const char *arm_idents[] = { | |
752 | "ARM C Compiler, ADS", | |
753 | "Thumb C Compiler, ADS", | |
754 | "ARM C++ Compiler, ADS", | |
755 | "Thumb C++ Compiler, ADS", | |
756 | "ARM/Thumb C/C++ Compiler, RVCT" | |
757 | }; | |
758 | int i; | |
759 | ||
760 | struct symtab *s; | |
761 | ||
762 | s = find_pc_symtab (fs->pc); | |
763 | if (s == NULL || s->producer == NULL) | |
764 | return; | |
765 | ||
766 | for (i = 0; i < ARRAY_SIZE (arm_idents); i++) | |
767 | if (strncmp (s->producer, arm_idents[i], strlen (arm_idents[i])) == 0) | |
768 | { | |
769 | if (fde->cie->version == 1) | |
770 | fs->armcc_cfa_offsets_sf = 1; | |
771 | ||
772 | if (fde->cie->version == 1) | |
773 | fs->armcc_cfa_offsets_reversed = 1; | |
774 | ||
775 | /* The reversed offset problem is present in some compilers | |
776 | using DWARF3, but it was eventually fixed. Check the ARM | |
777 | defined augmentations, which are in the format "armcc" followed | |
778 | by a list of one-character options. The "+" option means | |
779 | this problem is fixed (no quirk needed). If the armcc | |
780 | augmentation is missing, the quirk is needed. */ | |
781 | if (fde->cie->version == 3 | |
782 | && (strncmp (fde->cie->augmentation, "armcc", 5) != 0 | |
783 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) | |
784 | fs->armcc_cfa_offsets_reversed = 1; | |
785 | ||
786 | return; | |
787 | } | |
788 | } | |
8f22cb90 MK |
789 | \f |
790 | ||
791 | struct dwarf2_frame_cache | |
792 | { | |
793 | /* DWARF Call Frame Address. */ | |
794 | CORE_ADDR cfa; | |
795 | ||
0228dfb9 DJ |
796 | /* Set if the return address column was marked as undefined. */ |
797 | int undefined_retaddr; | |
798 | ||
8f22cb90 MK |
799 | /* Saved registers, indexed by GDB register number, not by DWARF |
800 | register number. */ | |
801 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
802 | |
803 | /* Return address register. */ | |
804 | struct dwarf2_frame_state_reg retaddr_reg; | |
8f22cb90 | 805 | }; |
05cbe71a | 806 | |
b9362cc7 | 807 | static struct dwarf2_frame_cache * |
cfc14b3a MK |
808 | dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache) |
809 | { | |
810 | struct cleanup *old_chain; | |
05cbe71a | 811 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
f57d151a UW |
812 | const int num_regs = gdbarch_num_regs (current_gdbarch) |
813 | + gdbarch_num_pseudo_regs (current_gdbarch); | |
cfc14b3a MK |
814 | struct dwarf2_frame_cache *cache; |
815 | struct dwarf2_frame_state *fs; | |
816 | struct dwarf2_fde *fde; | |
cfc14b3a MK |
817 | |
818 | if (*this_cache) | |
819 | return *this_cache; | |
820 | ||
821 | /* Allocate a new cache. */ | |
822 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
823 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
824 | ||
825 | /* Allocate and initialize the frame state. */ | |
826 | fs = XMALLOC (struct dwarf2_frame_state); | |
827 | memset (fs, 0, sizeof (struct dwarf2_frame_state)); | |
828 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); | |
829 | ||
830 | /* Unwind the PC. | |
831 | ||
832 | Note that if NEXT_FRAME is never supposed to return (i.e. a call | |
833 | to abort), the compiler might optimize away the instruction at | |
834 | NEXT_FRAME's return address. As a result the return address will | |
835 | point at some random instruction, and the CFI for that | |
e4e9607c | 836 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
837 | this problem by substracting 1 from the return address to get an |
838 | address in the middle of a presumed call instruction (or the | |
839 | instruction in the associated delay slot). This should only be | |
840 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c MK |
841 | handlers, sentinel frames, dummy frames). The function |
842 | frame_unwind_address_in_block does just this. It's not clear how | |
843 | reliable the method is though; there is the potential for the | |
844 | register state pre-call being different to that on return. */ | |
93d42b30 | 845 | fs->pc = frame_unwind_address_in_block (next_frame, NORMAL_FRAME); |
cfc14b3a MK |
846 | |
847 | /* Find the correct FDE. */ | |
848 | fde = dwarf2_frame_find_fde (&fs->pc); | |
849 | gdb_assert (fde != NULL); | |
850 | ||
851 | /* Extract any interesting information from the CIE. */ | |
852 | fs->data_align = fde->cie->data_alignment_factor; | |
853 | fs->code_align = fde->cie->code_alignment_factor; | |
854 | fs->retaddr_column = fde->cie->return_address_register; | |
855 | ||
303b6f5d DJ |
856 | /* Check for "quirks" - known bugs in producers. */ |
857 | dwarf2_frame_find_quirks (fs, fde); | |
858 | ||
cfc14b3a MK |
859 | /* First decode all the insns in the CIE. */ |
860 | execute_cfa_program (fde->cie->initial_instructions, | |
4bf8967c | 861 | fde->cie->end, next_frame, fs, fde->eh_frame_p); |
cfc14b3a MK |
862 | |
863 | /* Save the initialized register set. */ | |
864 | fs->initial = fs->regs; | |
865 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
866 | ||
867 | /* Then decode the insns in the FDE up to our target PC. */ | |
4bf8967c AS |
868 | execute_cfa_program (fde->instructions, fde->end, next_frame, fs, |
869 | fde->eh_frame_p); | |
cfc14b3a MK |
870 | |
871 | /* Caclulate the CFA. */ | |
872 | switch (fs->cfa_how) | |
873 | { | |
874 | case CFA_REG_OFFSET: | |
875 | cache->cfa = read_reg (next_frame, fs->cfa_reg); | |
303b6f5d DJ |
876 | if (fs->armcc_cfa_offsets_reversed) |
877 | cache->cfa -= fs->cfa_offset; | |
878 | else | |
879 | cache->cfa += fs->cfa_offset; | |
cfc14b3a MK |
880 | break; |
881 | ||
882 | case CFA_EXP: | |
883 | cache->cfa = | |
884 | execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0); | |
885 | break; | |
886 | ||
887 | default: | |
e2e0b3e5 | 888 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); |
cfc14b3a MK |
889 | } |
890 | ||
05cbe71a | 891 | /* Initialize the register state. */ |
3e2c4033 AC |
892 | { |
893 | int regnum; | |
e4e9607c | 894 | |
3e2c4033 | 895 | for (regnum = 0; regnum < num_regs; regnum++) |
aff37fc1 | 896 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], next_frame); |
3e2c4033 AC |
897 | } |
898 | ||
899 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
900 | location information in the cache. Note that we don't skip the |
901 | return address column; it's perfectly all right for it to | |
902 | correspond to a real register. If it doesn't correspond to a | |
903 | real register, or if we shouldn't treat it as such, | |
055d23b8 | 904 | gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside |
f57d151a | 905 | the range [0, gdbarch_num_regs). */ |
3e2c4033 AC |
906 | { |
907 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 908 | |
3e2c4033 AC |
909 | for (column = 0; column < fs->regs.num_regs; column++) |
910 | { | |
3e2c4033 | 911 | /* Use the GDB register number as the destination index. */ |
055d23b8 | 912 | int regnum = gdbarch_dwarf2_reg_to_regnum (current_gdbarch, column); |
3e2c4033 AC |
913 | |
914 | /* If there's no corresponding GDB register, ignore it. */ | |
915 | if (regnum < 0 || regnum >= num_regs) | |
916 | continue; | |
917 | ||
918 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
919 | of all debug info registers. If it doesn't, complain (but |
920 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
921 | unspecified register implies "same value" when CFI (draft |
922 | 7) specifies nothing at all. Such a register could equally | |
923 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
924 | isn't sufficient; it only checks that all registers in the |
925 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 926 | problems when a debug info register falls outside of the |
e4e9607c | 927 | table. We need a way of iterating through all the valid |
3e2c4033 | 928 | DWARF2 register numbers. */ |
05cbe71a | 929 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
930 | { |
931 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 AC |
932 | complaint (&symfile_complaints, _("\ |
933 | incomplete CFI data; unspecified registers (e.g., %s) at 0x%s"), | |
f059bf6f AC |
934 | gdbarch_register_name (gdbarch, regnum), |
935 | paddr_nz (fs->pc)); | |
936 | } | |
35889917 MK |
937 | else |
938 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
939 | } |
940 | } | |
cfc14b3a | 941 | |
8d5a9abc MK |
942 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
943 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
944 | { |
945 | int regnum; | |
946 | ||
947 | for (regnum = 0; regnum < num_regs; regnum++) | |
948 | { | |
8d5a9abc MK |
949 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
950 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 951 | { |
05cbe71a MK |
952 | struct dwarf2_frame_state_reg *retaddr_reg = |
953 | &fs->regs.reg[fs->retaddr_column]; | |
954 | ||
d4f10bf2 MK |
955 | /* It seems rather bizarre to specify an "empty" column as |
956 | the return adress column. However, this is exactly | |
957 | what GCC does on some targets. It turns out that GCC | |
958 | assumes that the return address can be found in the | |
959 | register corresponding to the return address column. | |
8d5a9abc MK |
960 | Incidentally, that's how we should treat a return |
961 | address column specifying "same value" too. */ | |
d4f10bf2 | 962 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
963 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
964 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
965 | { |
966 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
967 | cache->reg[regnum] = *retaddr_reg; | |
968 | else | |
969 | cache->retaddr_reg = *retaddr_reg; | |
970 | } | |
35889917 MK |
971 | else |
972 | { | |
8d5a9abc MK |
973 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
974 | { | |
975 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
976 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
977 | } | |
978 | else | |
979 | { | |
980 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
981 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
982 | } | |
35889917 MK |
983 | } |
984 | } | |
985 | } | |
986 | } | |
cfc14b3a | 987 | |
0228dfb9 DJ |
988 | if (fs->retaddr_column < fs->regs.num_regs |
989 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
990 | cache->undefined_retaddr = 1; | |
991 | ||
cfc14b3a MK |
992 | do_cleanups (old_chain); |
993 | ||
994 | *this_cache = cache; | |
995 | return cache; | |
996 | } | |
997 | ||
998 | static void | |
999 | dwarf2_frame_this_id (struct frame_info *next_frame, void **this_cache, | |
1000 | struct frame_id *this_id) | |
1001 | { | |
1002 | struct dwarf2_frame_cache *cache = | |
1003 | dwarf2_frame_cache (next_frame, this_cache); | |
1004 | ||
0228dfb9 DJ |
1005 | if (cache->undefined_retaddr) |
1006 | return; | |
1007 | ||
93d42b30 DJ |
1008 | (*this_id) = frame_id_build (cache->cfa, |
1009 | frame_func_unwind (next_frame, NORMAL_FRAME)); | |
1010 | } | |
1011 | ||
1012 | static void | |
1013 | dwarf2_signal_frame_this_id (struct frame_info *next_frame, void **this_cache, | |
1014 | struct frame_id *this_id) | |
1015 | { | |
1016 | struct dwarf2_frame_cache *cache = | |
1017 | dwarf2_frame_cache (next_frame, this_cache); | |
1018 | ||
1019 | if (cache->undefined_retaddr) | |
1020 | return; | |
1021 | ||
1022 | (*this_id) = frame_id_build (cache->cfa, | |
1023 | frame_func_unwind (next_frame, SIGTRAMP_FRAME)); | |
cfc14b3a MK |
1024 | } |
1025 | ||
1026 | static void | |
1027 | dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache, | |
1028 | int regnum, int *optimizedp, | |
1029 | enum lval_type *lvalp, CORE_ADDR *addrp, | |
c6826062 | 1030 | int *realnump, gdb_byte *valuep) |
cfc14b3a | 1031 | { |
05cbe71a | 1032 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a MK |
1033 | struct dwarf2_frame_cache *cache = |
1034 | dwarf2_frame_cache (next_frame, this_cache); | |
1035 | ||
1036 | switch (cache->reg[regnum].how) | |
1037 | { | |
05cbe71a | 1038 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1039 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1040 | mark it as optimized away; the value isn't available. */ |
cfc14b3a MK |
1041 | *optimizedp = 1; |
1042 | *lvalp = not_lval; | |
1043 | *addrp = 0; | |
1044 | *realnump = -1; | |
35889917 | 1045 | if (valuep) |
cfc14b3a MK |
1046 | { |
1047 | /* In some cases, for example %eflags on the i386, we have | |
1048 | to provide a sane value, even though this register wasn't | |
1049 | saved. Assume we can get it from NEXT_FRAME. */ | |
1050 | frame_unwind_register (next_frame, regnum, valuep); | |
1051 | } | |
1052 | break; | |
1053 | ||
05cbe71a | 1054 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
cfc14b3a MK |
1055 | *optimizedp = 0; |
1056 | *lvalp = lval_memory; | |
1057 | *addrp = cache->cfa + cache->reg[regnum].loc.offset; | |
1058 | *realnump = -1; | |
1059 | if (valuep) | |
1060 | { | |
1061 | /* Read the value in from memory. */ | |
05cbe71a | 1062 | read_memory (*addrp, valuep, register_size (gdbarch, regnum)); |
cfc14b3a MK |
1063 | } |
1064 | break; | |
1065 | ||
05cbe71a | 1066 | case DWARF2_FRAME_REG_SAVED_REG: |
00b25ff3 AC |
1067 | *optimizedp = 0; |
1068 | *lvalp = lval_register; | |
1069 | *addrp = 0; | |
055d23b8 UW |
1070 | *realnump = gdbarch_dwarf2_reg_to_regnum |
1071 | (current_gdbarch, cache->reg[regnum].loc.reg); | |
00b25ff3 AC |
1072 | if (valuep) |
1073 | frame_unwind_register (next_frame, (*realnump), valuep); | |
cfc14b3a MK |
1074 | break; |
1075 | ||
05cbe71a | 1076 | case DWARF2_FRAME_REG_SAVED_EXP: |
cfc14b3a MK |
1077 | *optimizedp = 0; |
1078 | *lvalp = lval_memory; | |
1079 | *addrp = execute_stack_op (cache->reg[regnum].loc.exp, | |
1080 | cache->reg[regnum].exp_len, | |
1081 | next_frame, cache->cfa); | |
1082 | *realnump = -1; | |
1083 | if (valuep) | |
1084 | { | |
1085 | /* Read the value in from memory. */ | |
05cbe71a | 1086 | read_memory (*addrp, valuep, register_size (gdbarch, regnum)); |
cfc14b3a MK |
1087 | } |
1088 | break; | |
1089 | ||
46ea248b AO |
1090 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
1091 | *optimizedp = 0; | |
1092 | *lvalp = not_lval; | |
1093 | *addrp = 0; | |
1094 | *realnump = -1; | |
1095 | if (valuep) | |
1096 | store_unsigned_integer (valuep, register_size (gdbarch, regnum), | |
1097 | cache->cfa + cache->reg[regnum].loc.offset); | |
1098 | break; | |
1099 | ||
1100 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
1101 | *optimizedp = 0; | |
1102 | *lvalp = not_lval; | |
1103 | *addrp = 0; | |
1104 | *realnump = -1; | |
1105 | if (valuep) | |
1106 | store_unsigned_integer (valuep, register_size (gdbarch, regnum), | |
1107 | execute_stack_op (cache->reg[regnum].loc.exp, | |
1108 | cache->reg[regnum].exp_len, | |
1109 | next_frame, cache->cfa)); | |
1110 | break; | |
1111 | ||
05cbe71a | 1112 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1113 | /* GCC, in its infinite wisdom decided to not provide unwind |
1114 | information for registers that are "same value". Since | |
1115 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1116 | registers are actually undefined (which is different to CFI | |
1117 | "undefined"). Code above issues a complaint about this. | |
1118 | Here just fudge the books, assume GCC, and that the value is | |
1119 | more inner on the stack. */ | |
00b25ff3 AC |
1120 | *optimizedp = 0; |
1121 | *lvalp = lval_register; | |
1122 | *addrp = 0; | |
1123 | *realnump = regnum; | |
1124 | if (valuep) | |
1125 | frame_unwind_register (next_frame, (*realnump), valuep); | |
3e2c4033 AC |
1126 | break; |
1127 | ||
05cbe71a | 1128 | case DWARF2_FRAME_REG_SAME_VALUE: |
00b25ff3 AC |
1129 | *optimizedp = 0; |
1130 | *lvalp = lval_register; | |
1131 | *addrp = 0; | |
1132 | *realnump = regnum; | |
1133 | if (valuep) | |
1134 | frame_unwind_register (next_frame, (*realnump), valuep); | |
cfc14b3a MK |
1135 | break; |
1136 | ||
05cbe71a | 1137 | case DWARF2_FRAME_REG_CFA: |
35889917 MK |
1138 | *optimizedp = 0; |
1139 | *lvalp = not_lval; | |
1140 | *addrp = 0; | |
1141 | *realnump = -1; | |
1142 | if (valuep) | |
14d06750 | 1143 | pack_long (valuep, register_type (gdbarch, regnum), cache->cfa); |
35889917 MK |
1144 | break; |
1145 | ||
ea7963f0 FR |
1146 | case DWARF2_FRAME_REG_CFA_OFFSET: |
1147 | *optimizedp = 0; | |
1148 | *lvalp = not_lval; | |
1149 | *addrp = 0; | |
1150 | *realnump = -1; | |
1151 | if (valuep) | |
14d06750 DJ |
1152 | pack_long (valuep, register_type (gdbarch, regnum), |
1153 | cache->cfa + cache->reg[regnum].loc.offset); | |
ea7963f0 FR |
1154 | break; |
1155 | ||
8d5a9abc MK |
1156 | case DWARF2_FRAME_REG_RA_OFFSET: |
1157 | *optimizedp = 0; | |
1158 | *lvalp = not_lval; | |
1159 | *addrp = 0; | |
1160 | *realnump = -1; | |
1161 | if (valuep) | |
1162 | { | |
1163 | CORE_ADDR pc = cache->reg[regnum].loc.offset; | |
1164 | ||
055d23b8 UW |
1165 | regnum = gdbarch_dwarf2_reg_to_regnum |
1166 | (current_gdbarch, cache->retaddr_reg.loc.reg); | |
8d5a9abc | 1167 | pc += frame_unwind_register_unsigned (next_frame, regnum); |
14d06750 | 1168 | pack_long (valuep, register_type (gdbarch, regnum), pc); |
8d5a9abc MK |
1169 | } |
1170 | break; | |
1171 | ||
cfc14b3a | 1172 | default: |
e2e0b3e5 | 1173 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1174 | } |
1175 | } | |
1176 | ||
1177 | static const struct frame_unwind dwarf2_frame_unwind = | |
1178 | { | |
1179 | NORMAL_FRAME, | |
1180 | dwarf2_frame_this_id, | |
1181 | dwarf2_frame_prev_register | |
1182 | }; | |
1183 | ||
3ed09a32 DJ |
1184 | static const struct frame_unwind dwarf2_signal_frame_unwind = |
1185 | { | |
1186 | SIGTRAMP_FRAME, | |
93d42b30 | 1187 | dwarf2_signal_frame_this_id, |
3ed09a32 DJ |
1188 | dwarf2_frame_prev_register |
1189 | }; | |
1190 | ||
cfc14b3a | 1191 | const struct frame_unwind * |
336d1bba | 1192 | dwarf2_frame_sniffer (struct frame_info *next_frame) |
cfc14b3a | 1193 | { |
1ce5d6dd AC |
1194 | /* Grab an address that is guarenteed to reside somewhere within the |
1195 | function. frame_pc_unwind(), for a no-return next function, can | |
93d42b30 DJ |
1196 | end up returning something past the end of this function's body. |
1197 | If the frame we're sniffing for is a signal frame whose start | |
1198 | address is placed on the stack by the OS, its FDE must | |
1199 | extend one byte before its start address or we will miss it. */ | |
1200 | CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame, | |
1201 | NORMAL_FRAME); | |
56c987f6 AO |
1202 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr); |
1203 | if (!fde) | |
3ed09a32 DJ |
1204 | return NULL; |
1205 | ||
1206 | /* On some targets, signal trampolines may have unwind information. | |
1207 | We need to recognize them so that we set the frame type | |
1208 | correctly. */ | |
1209 | ||
56c987f6 AO |
1210 | if (fde->cie->signal_frame |
1211 | || dwarf2_frame_signal_frame_p (get_frame_arch (next_frame), | |
1212 | next_frame)) | |
3ed09a32 | 1213 | return &dwarf2_signal_frame_unwind; |
cfc14b3a | 1214 | |
3ed09a32 | 1215 | return &dwarf2_frame_unwind; |
cfc14b3a MK |
1216 | } |
1217 | \f | |
1218 | ||
1219 | /* There is no explicitly defined relationship between the CFA and the | |
1220 | location of frame's local variables and arguments/parameters. | |
1221 | Therefore, frame base methods on this page should probably only be | |
1222 | used as a last resort, just to avoid printing total garbage as a | |
1223 | response to the "info frame" command. */ | |
1224 | ||
1225 | static CORE_ADDR | |
1226 | dwarf2_frame_base_address (struct frame_info *next_frame, void **this_cache) | |
1227 | { | |
1228 | struct dwarf2_frame_cache *cache = | |
1229 | dwarf2_frame_cache (next_frame, this_cache); | |
1230 | ||
1231 | return cache->cfa; | |
1232 | } | |
1233 | ||
1234 | static const struct frame_base dwarf2_frame_base = | |
1235 | { | |
1236 | &dwarf2_frame_unwind, | |
1237 | dwarf2_frame_base_address, | |
1238 | dwarf2_frame_base_address, | |
1239 | dwarf2_frame_base_address | |
1240 | }; | |
1241 | ||
1242 | const struct frame_base * | |
336d1bba | 1243 | dwarf2_frame_base_sniffer (struct frame_info *next_frame) |
cfc14b3a | 1244 | { |
93d42b30 DJ |
1245 | CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame, |
1246 | NORMAL_FRAME); | |
1247 | if (dwarf2_frame_find_fde (&block_addr)) | |
cfc14b3a MK |
1248 | return &dwarf2_frame_base; |
1249 | ||
1250 | return NULL; | |
1251 | } | |
1252 | \f | |
1253 | /* A minimal decoding of DWARF2 compilation units. We only decode | |
1254 | what's needed to get to the call frame information. */ | |
1255 | ||
1256 | struct comp_unit | |
1257 | { | |
1258 | /* Keep the bfd convenient. */ | |
1259 | bfd *abfd; | |
1260 | ||
1261 | struct objfile *objfile; | |
1262 | ||
1263 | /* Linked list of CIEs for this object. */ | |
1264 | struct dwarf2_cie *cie; | |
1265 | ||
cfc14b3a | 1266 | /* Pointer to the .debug_frame section loaded into memory. */ |
852483bc | 1267 | gdb_byte *dwarf_frame_buffer; |
cfc14b3a MK |
1268 | |
1269 | /* Length of the loaded .debug_frame section. */ | |
1270 | unsigned long dwarf_frame_size; | |
1271 | ||
1272 | /* Pointer to the .debug_frame section. */ | |
1273 | asection *dwarf_frame_section; | |
0912c7f2 MK |
1274 | |
1275 | /* Base for DW_EH_PE_datarel encodings. */ | |
1276 | bfd_vma dbase; | |
0fd85043 CV |
1277 | |
1278 | /* Base for DW_EH_PE_textrel encodings. */ | |
1279 | bfd_vma tbase; | |
cfc14b3a MK |
1280 | }; |
1281 | ||
8f22cb90 | 1282 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1283 | |
cfc14b3a | 1284 | static unsigned int |
852483bc | 1285 | read_1_byte (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1286 | { |
852483bc | 1287 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1288 | } |
1289 | ||
1290 | static unsigned int | |
852483bc | 1291 | read_4_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1292 | { |
852483bc | 1293 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1294 | } |
1295 | ||
1296 | static ULONGEST | |
852483bc | 1297 | read_8_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1298 | { |
852483bc | 1299 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1300 | } |
1301 | ||
1302 | static ULONGEST | |
852483bc | 1303 | read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1304 | { |
1305 | ULONGEST result; | |
1306 | unsigned int num_read; | |
1307 | int shift; | |
852483bc | 1308 | gdb_byte byte; |
cfc14b3a MK |
1309 | |
1310 | result = 0; | |
1311 | shift = 0; | |
1312 | num_read = 0; | |
1313 | ||
1314 | do | |
1315 | { | |
1316 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1317 | buf++; | |
1318 | num_read++; | |
1319 | result |= ((byte & 0x7f) << shift); | |
1320 | shift += 7; | |
1321 | } | |
1322 | while (byte & 0x80); | |
1323 | ||
1324 | *bytes_read_ptr = num_read; | |
1325 | ||
1326 | return result; | |
1327 | } | |
1328 | ||
1329 | static LONGEST | |
852483bc | 1330 | read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1331 | { |
1332 | LONGEST result; | |
1333 | int shift; | |
1334 | unsigned int num_read; | |
852483bc | 1335 | gdb_byte byte; |
cfc14b3a MK |
1336 | |
1337 | result = 0; | |
1338 | shift = 0; | |
1339 | num_read = 0; | |
1340 | ||
1341 | do | |
1342 | { | |
1343 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1344 | buf++; | |
1345 | num_read++; | |
1346 | result |= ((byte & 0x7f) << shift); | |
1347 | shift += 7; | |
1348 | } | |
1349 | while (byte & 0x80); | |
1350 | ||
77e0b926 DJ |
1351 | if (shift < 8 * sizeof (result) && (byte & 0x40)) |
1352 | result |= -(((LONGEST)1) << shift); | |
cfc14b3a MK |
1353 | |
1354 | *bytes_read_ptr = num_read; | |
1355 | ||
1356 | return result; | |
1357 | } | |
1358 | ||
1359 | static ULONGEST | |
852483bc | 1360 | read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1361 | { |
1362 | LONGEST result; | |
1363 | ||
852483bc | 1364 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1365 | if (result == 0xffffffff) |
1366 | { | |
852483bc | 1367 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1368 | *bytes_read_ptr = 12; |
1369 | } | |
1370 | else | |
1371 | *bytes_read_ptr = 4; | |
1372 | ||
1373 | return result; | |
1374 | } | |
1375 | \f | |
1376 | ||
1377 | /* Pointer encoding helper functions. */ | |
1378 | ||
1379 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1380 | technical reasons, it encodes addresses in its FDE's in a different | |
1381 | way. Several "pointer encodings" are supported. The encoding | |
1382 | that's used for a particular FDE is determined by the 'R' | |
1383 | augmentation in the associated CIE. The argument of this | |
1384 | augmentation is a single byte. | |
1385 | ||
1386 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1387 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1388 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1389 | address should be interpreted (absolute, relative to the current | |
1390 | position in the FDE, ...). Bit 7, indicates that the address | |
1391 | should be dereferenced. */ | |
1392 | ||
852483bc | 1393 | static gdb_byte |
cfc14b3a MK |
1394 | encoding_for_size (unsigned int size) |
1395 | { | |
1396 | switch (size) | |
1397 | { | |
1398 | case 2: | |
1399 | return DW_EH_PE_udata2; | |
1400 | case 4: | |
1401 | return DW_EH_PE_udata4; | |
1402 | case 8: | |
1403 | return DW_EH_PE_udata8; | |
1404 | default: | |
e2e0b3e5 | 1405 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1406 | } |
1407 | } | |
1408 | ||
1409 | static unsigned int | |
852483bc | 1410 | size_of_encoded_value (gdb_byte encoding) |
cfc14b3a MK |
1411 | { |
1412 | if (encoding == DW_EH_PE_omit) | |
1413 | return 0; | |
1414 | ||
1415 | switch (encoding & 0x07) | |
1416 | { | |
1417 | case DW_EH_PE_absptr: | |
1418 | return TYPE_LENGTH (builtin_type_void_data_ptr); | |
1419 | case DW_EH_PE_udata2: | |
1420 | return 2; | |
1421 | case DW_EH_PE_udata4: | |
1422 | return 4; | |
1423 | case DW_EH_PE_udata8: | |
1424 | return 8; | |
1425 | default: | |
e2e0b3e5 | 1426 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1427 | } |
1428 | } | |
1429 | ||
1430 | static CORE_ADDR | |
852483bc MK |
1431 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
1432 | gdb_byte *buf, unsigned int *bytes_read_ptr) | |
cfc14b3a | 1433 | { |
68f6cf99 MK |
1434 | int ptr_len = size_of_encoded_value (DW_EH_PE_absptr); |
1435 | ptrdiff_t offset; | |
cfc14b3a MK |
1436 | CORE_ADDR base; |
1437 | ||
1438 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1439 | FDE's. */ | |
1440 | if (encoding & DW_EH_PE_indirect) | |
1441 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1442 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1443 | |
68f6cf99 MK |
1444 | *bytes_read_ptr = 0; |
1445 | ||
cfc14b3a MK |
1446 | switch (encoding & 0x70) |
1447 | { | |
1448 | case DW_EH_PE_absptr: | |
1449 | base = 0; | |
1450 | break; | |
1451 | case DW_EH_PE_pcrel: | |
f2fec864 | 1452 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1453 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1454 | break; |
0912c7f2 MK |
1455 | case DW_EH_PE_datarel: |
1456 | base = unit->dbase; | |
1457 | break; | |
0fd85043 CV |
1458 | case DW_EH_PE_textrel: |
1459 | base = unit->tbase; | |
1460 | break; | |
03ac2a74 MK |
1461 | case DW_EH_PE_funcrel: |
1462 | /* FIXME: kettenis/20040501: For now just pretend | |
1463 | DW_EH_PE_funcrel is equivalent to DW_EH_PE_absptr. For | |
1464 | reading the initial location of an FDE it should be treated | |
1465 | as such, and currently that's the only place where this code | |
1466 | is used. */ | |
1467 | base = 0; | |
1468 | break; | |
68f6cf99 MK |
1469 | case DW_EH_PE_aligned: |
1470 | base = 0; | |
852483bc | 1471 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1472 | if ((offset % ptr_len) != 0) |
1473 | { | |
1474 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1475 | buf += *bytes_read_ptr; | |
1476 | } | |
1477 | break; | |
cfc14b3a | 1478 | default: |
e2e0b3e5 | 1479 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1480 | } |
1481 | ||
b04de778 | 1482 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1483 | { |
1484 | encoding |= encoding_for_size (ptr_len); | |
1485 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1486 | encoding |= DW_EH_PE_signed; | |
1487 | } | |
cfc14b3a MK |
1488 | |
1489 | switch (encoding & 0x0f) | |
1490 | { | |
a81b10ae MK |
1491 | case DW_EH_PE_uleb128: |
1492 | { | |
1493 | ULONGEST value; | |
852483bc | 1494 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1495 | *bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1496 | return base + value; |
1497 | } | |
cfc14b3a | 1498 | case DW_EH_PE_udata2: |
68f6cf99 | 1499 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1500 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1501 | case DW_EH_PE_udata4: | |
68f6cf99 | 1502 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1503 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1504 | case DW_EH_PE_udata8: | |
68f6cf99 | 1505 | *bytes_read_ptr += 8; |
cfc14b3a | 1506 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1507 | case DW_EH_PE_sleb128: |
1508 | { | |
1509 | LONGEST value; | |
852483bc | 1510 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1511 | *bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1512 | return base + value; |
1513 | } | |
cfc14b3a | 1514 | case DW_EH_PE_sdata2: |
68f6cf99 | 1515 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1516 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1517 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1518 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1519 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1520 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1521 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1522 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1523 | default: | |
e2e0b3e5 | 1524 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1525 | } |
1526 | } | |
1527 | \f | |
1528 | ||
1529 | /* GCC uses a single CIE for all FDEs in a .debug_frame section. | |
1530 | That's why we use a simple linked list here. */ | |
1531 | ||
1532 | static struct dwarf2_cie * | |
1533 | find_cie (struct comp_unit *unit, ULONGEST cie_pointer) | |
1534 | { | |
1535 | struct dwarf2_cie *cie = unit->cie; | |
1536 | ||
1537 | while (cie) | |
1538 | { | |
1539 | if (cie->cie_pointer == cie_pointer) | |
1540 | return cie; | |
1541 | ||
1542 | cie = cie->next; | |
1543 | } | |
1544 | ||
1545 | return NULL; | |
1546 | } | |
1547 | ||
1548 | static void | |
1549 | add_cie (struct comp_unit *unit, struct dwarf2_cie *cie) | |
1550 | { | |
1551 | cie->next = unit->cie; | |
1552 | unit->cie = cie; | |
1553 | } | |
1554 | ||
1555 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1556 | inital location associated with it into *PC. */ | |
1557 | ||
1558 | static struct dwarf2_fde * | |
1559 | dwarf2_frame_find_fde (CORE_ADDR *pc) | |
1560 | { | |
1561 | struct objfile *objfile; | |
1562 | ||
1563 | ALL_OBJFILES (objfile) | |
1564 | { | |
1565 | struct dwarf2_fde *fde; | |
1566 | CORE_ADDR offset; | |
1567 | ||
8f22cb90 | 1568 | fde = objfile_data (objfile, dwarf2_frame_objfile_data); |
4ae9ee8e DJ |
1569 | if (fde == NULL) |
1570 | continue; | |
1571 | ||
1572 | gdb_assert (objfile->section_offsets); | |
1573 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1574 | ||
cfc14b3a MK |
1575 | while (fde) |
1576 | { | |
1577 | if (*pc >= fde->initial_location + offset | |
1578 | && *pc < fde->initial_location + offset + fde->address_range) | |
1579 | { | |
1580 | *pc = fde->initial_location + offset; | |
1581 | return fde; | |
1582 | } | |
1583 | ||
1584 | fde = fde->next; | |
1585 | } | |
1586 | } | |
1587 | ||
1588 | return NULL; | |
1589 | } | |
1590 | ||
1591 | static void | |
1592 | add_fde (struct comp_unit *unit, struct dwarf2_fde *fde) | |
1593 | { | |
8f22cb90 MK |
1594 | fde->next = objfile_data (unit->objfile, dwarf2_frame_objfile_data); |
1595 | set_objfile_data (unit->objfile, dwarf2_frame_objfile_data, fde); | |
cfc14b3a MK |
1596 | } |
1597 | ||
1598 | #ifdef CC_HAS_LONG_LONG | |
1599 | #define DW64_CIE_ID 0xffffffffffffffffULL | |
1600 | #else | |
1601 | #define DW64_CIE_ID ~0 | |
1602 | #endif | |
1603 | ||
852483bc MK |
1604 | static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start, |
1605 | int eh_frame_p); | |
cfc14b3a | 1606 | |
6896c0c7 RH |
1607 | /* Decode the next CIE or FDE. Return NULL if invalid input, otherwise |
1608 | the next byte to be processed. */ | |
852483bc MK |
1609 | static gdb_byte * |
1610 | decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
cfc14b3a | 1611 | { |
852483bc | 1612 | gdb_byte *buf, *end; |
cfc14b3a MK |
1613 | LONGEST length; |
1614 | unsigned int bytes_read; | |
6896c0c7 RH |
1615 | int dwarf64_p; |
1616 | ULONGEST cie_id; | |
cfc14b3a | 1617 | ULONGEST cie_pointer; |
cfc14b3a | 1618 | |
6896c0c7 | 1619 | buf = start; |
cfc14b3a MK |
1620 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1621 | buf += bytes_read; | |
1622 | end = buf + length; | |
1623 | ||
6896c0c7 RH |
1624 | /* Are we still within the section? */ |
1625 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1626 | return NULL; | |
1627 | ||
cfc14b3a MK |
1628 | if (length == 0) |
1629 | return end; | |
1630 | ||
6896c0c7 RH |
1631 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1632 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1633 | |
6896c0c7 | 1634 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1635 | if (eh_frame_p) |
1636 | cie_id = 0; | |
1637 | else if (dwarf64_p) | |
1638 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1639 | else |
1640 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1641 | |
1642 | if (dwarf64_p) | |
1643 | { | |
1644 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1645 | buf += 8; | |
1646 | } | |
1647 | else | |
1648 | { | |
1649 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1650 | buf += 4; | |
1651 | } | |
1652 | ||
1653 | if (cie_pointer == cie_id) | |
1654 | { | |
1655 | /* This is a CIE. */ | |
1656 | struct dwarf2_cie *cie; | |
1657 | char *augmentation; | |
28ba0b33 | 1658 | unsigned int cie_version; |
cfc14b3a MK |
1659 | |
1660 | /* Record the offset into the .debug_frame section of this CIE. */ | |
1661 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1662 | ||
1663 | /* Check whether we've already read it. */ | |
1664 | if (find_cie (unit, cie_pointer)) | |
1665 | return end; | |
1666 | ||
1667 | cie = (struct dwarf2_cie *) | |
8b92e4d5 | 1668 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1669 | sizeof (struct dwarf2_cie)); |
1670 | cie->initial_instructions = NULL; | |
1671 | cie->cie_pointer = cie_pointer; | |
1672 | ||
1673 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1674 | depends on the target address size. */ |
1675 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1676 | |
56c987f6 AO |
1677 | /* We'll determine the final value later, but we need to |
1678 | initialize it conservatively. */ | |
1679 | cie->signal_frame = 0; | |
1680 | ||
cfc14b3a | 1681 | /* Check version number. */ |
28ba0b33 PB |
1682 | cie_version = read_1_byte (unit->abfd, buf); |
1683 | if (cie_version != 1 && cie_version != 3) | |
6896c0c7 | 1684 | return NULL; |
303b6f5d | 1685 | cie->version = cie_version; |
cfc14b3a MK |
1686 | buf += 1; |
1687 | ||
1688 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1689 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1690 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1691 | |
303b6f5d DJ |
1692 | /* Ignore armcc augmentations. We only use them for quirks, |
1693 | and that doesn't happen until later. */ | |
1694 | if (strncmp (augmentation, "armcc", 5) == 0) | |
1695 | augmentation += strlen (augmentation); | |
1696 | ||
cfc14b3a MK |
1697 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1698 | following the augmentation string, so it must be handled | |
1699 | first. */ | |
1700 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1701 | { | |
1702 | /* Skip. */ | |
1703 | buf += TYPE_LENGTH (builtin_type_void_data_ptr); | |
1704 | augmentation += 2; | |
1705 | } | |
1706 | ||
1707 | cie->code_alignment_factor = | |
1708 | read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1709 | buf += bytes_read; | |
1710 | ||
1711 | cie->data_alignment_factor = | |
1712 | read_signed_leb128 (unit->abfd, buf, &bytes_read); | |
1713 | buf += bytes_read; | |
1714 | ||
28ba0b33 PB |
1715 | if (cie_version == 1) |
1716 | { | |
1717 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
1718 | bytes_read = 1; | |
1719 | } | |
1720 | else | |
1721 | cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf, | |
1722 | &bytes_read); | |
4fc771b8 DJ |
1723 | cie->return_address_register |
1724 | = dwarf2_frame_adjust_regnum (current_gdbarch, | |
1725 | cie->return_address_register, | |
1726 | eh_frame_p); | |
4bf8967c | 1727 | |
28ba0b33 | 1728 | buf += bytes_read; |
cfc14b3a | 1729 | |
7131cb6e RH |
1730 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1731 | if (cie->saw_z_augmentation) | |
cfc14b3a MK |
1732 | { |
1733 | ULONGEST length; | |
1734 | ||
1735 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1736 | buf += bytes_read; | |
6896c0c7 RH |
1737 | if (buf > end) |
1738 | return NULL; | |
cfc14b3a MK |
1739 | cie->initial_instructions = buf + length; |
1740 | augmentation++; | |
1741 | } | |
1742 | ||
1743 | while (*augmentation) | |
1744 | { | |
1745 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1746 | if (*augmentation == 'L') | |
1747 | { | |
1748 | /* Skip. */ | |
1749 | buf++; | |
1750 | augmentation++; | |
1751 | } | |
1752 | ||
1753 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1754 | else if (*augmentation == 'R') | |
1755 | { | |
1756 | cie->encoding = *buf++; | |
1757 | augmentation++; | |
1758 | } | |
1759 | ||
1760 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1761 | else if (*augmentation == 'P') | |
1762 | { | |
1234d960 | 1763 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1764 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
f724bf08 MK |
1765 | read_encoded_value (unit, encoding, buf, &bytes_read); |
1766 | buf += bytes_read; | |
cfc14b3a MK |
1767 | augmentation++; |
1768 | } | |
1769 | ||
56c987f6 AO |
1770 | /* "S" indicates a signal frame, such that the return |
1771 | address must not be decremented to locate the call frame | |
1772 | info for the previous frame; it might even be the first | |
1773 | instruction of a function, so decrementing it would take | |
1774 | us to a different function. */ | |
1775 | else if (*augmentation == 'S') | |
1776 | { | |
1777 | cie->signal_frame = 1; | |
1778 | augmentation++; | |
1779 | } | |
1780 | ||
3e9a2e52 DJ |
1781 | /* Otherwise we have an unknown augmentation. Assume that either |
1782 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1783 | else |
1784 | { | |
3e9a2e52 DJ |
1785 | if (cie->initial_instructions) |
1786 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1787 | break; |
1788 | } | |
1789 | } | |
1790 | ||
1791 | cie->initial_instructions = buf; | |
1792 | cie->end = end; | |
1793 | ||
1794 | add_cie (unit, cie); | |
1795 | } | |
1796 | else | |
1797 | { | |
1798 | /* This is a FDE. */ | |
1799 | struct dwarf2_fde *fde; | |
1800 | ||
6896c0c7 RH |
1801 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1802 | address within the FDE where the CIE pointer is stored and the | |
1803 | address of the CIE. Convert it to an offset into the .eh_frame | |
1804 | section. */ | |
cfc14b3a MK |
1805 | if (eh_frame_p) |
1806 | { | |
cfc14b3a MK |
1807 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1808 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1809 | } | |
1810 | ||
6896c0c7 RH |
1811 | /* In either case, validate the result is still within the section. */ |
1812 | if (cie_pointer >= unit->dwarf_frame_size) | |
1813 | return NULL; | |
1814 | ||
cfc14b3a | 1815 | fde = (struct dwarf2_fde *) |
8b92e4d5 | 1816 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1817 | sizeof (struct dwarf2_fde)); |
1818 | fde->cie = find_cie (unit, cie_pointer); | |
1819 | if (fde->cie == NULL) | |
1820 | { | |
1821 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
1822 | eh_frame_p); | |
1823 | fde->cie = find_cie (unit, cie_pointer); | |
1824 | } | |
1825 | ||
1826 | gdb_assert (fde->cie != NULL); | |
1827 | ||
1828 | fde->initial_location = | |
1829 | read_encoded_value (unit, fde->cie->encoding, buf, &bytes_read); | |
1830 | buf += bytes_read; | |
1831 | ||
1832 | fde->address_range = | |
1833 | read_encoded_value (unit, fde->cie->encoding & 0x0f, buf, &bytes_read); | |
1834 | buf += bytes_read; | |
1835 | ||
7131cb6e RH |
1836 | /* A 'z' augmentation in the CIE implies the presence of an |
1837 | augmentation field in the FDE as well. The only thing known | |
1838 | to be in here at present is the LSDA entry for EH. So we | |
1839 | can skip the whole thing. */ | |
1840 | if (fde->cie->saw_z_augmentation) | |
1841 | { | |
1842 | ULONGEST length; | |
1843 | ||
1844 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1845 | buf += bytes_read + length; | |
6896c0c7 RH |
1846 | if (buf > end) |
1847 | return NULL; | |
7131cb6e RH |
1848 | } |
1849 | ||
cfc14b3a MK |
1850 | fde->instructions = buf; |
1851 | fde->end = end; | |
1852 | ||
4bf8967c AS |
1853 | fde->eh_frame_p = eh_frame_p; |
1854 | ||
cfc14b3a MK |
1855 | add_fde (unit, fde); |
1856 | } | |
1857 | ||
1858 | return end; | |
1859 | } | |
6896c0c7 RH |
1860 | |
1861 | /* Read a CIE or FDE in BUF and decode it. */ | |
852483bc MK |
1862 | static gdb_byte * |
1863 | decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
6896c0c7 RH |
1864 | { |
1865 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
852483bc | 1866 | gdb_byte *ret; |
6896c0c7 RH |
1867 | const char *msg; |
1868 | ptrdiff_t start_offset; | |
1869 | ||
1870 | while (1) | |
1871 | { | |
1872 | ret = decode_frame_entry_1 (unit, start, eh_frame_p); | |
1873 | if (ret != NULL) | |
1874 | break; | |
1875 | ||
1876 | /* We have corrupt input data of some form. */ | |
1877 | ||
1878 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
1879 | and mismatches wrt padding and alignment of debug sections. */ | |
1880 | /* Note that there is no requirement in the standard for any | |
1881 | alignment at all in the frame unwind sections. Testing for | |
1882 | alignment before trying to interpret data would be incorrect. | |
1883 | ||
1884 | However, GCC traditionally arranged for frame sections to be | |
1885 | sized such that the FDE length and CIE fields happen to be | |
1886 | aligned (in theory, for performance). This, unfortunately, | |
1887 | was done with .align directives, which had the side effect of | |
1888 | forcing the section to be aligned by the linker. | |
1889 | ||
1890 | This becomes a problem when you have some other producer that | |
1891 | creates frame sections that are not as strictly aligned. That | |
1892 | produces a hole in the frame info that gets filled by the | |
1893 | linker with zeros. | |
1894 | ||
1895 | The GCC behaviour is arguably a bug, but it's effectively now | |
1896 | part of the ABI, so we're now stuck with it, at least at the | |
1897 | object file level. A smart linker may decide, in the process | |
1898 | of compressing duplicate CIE information, that it can rewrite | |
1899 | the entire output section without this extra padding. */ | |
1900 | ||
1901 | start_offset = start - unit->dwarf_frame_buffer; | |
1902 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
1903 | { | |
1904 | start += 4 - (start_offset & 3); | |
1905 | workaround = ALIGN4; | |
1906 | continue; | |
1907 | } | |
1908 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
1909 | { | |
1910 | start += 8 - (start_offset & 7); | |
1911 | workaround = ALIGN8; | |
1912 | continue; | |
1913 | } | |
1914 | ||
1915 | /* Nothing left to try. Arrange to return as if we've consumed | |
1916 | the entire input section. Hopefully we'll get valid info from | |
1917 | the other of .debug_frame/.eh_frame. */ | |
1918 | workaround = FAIL; | |
1919 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
1920 | break; | |
1921 | } | |
1922 | ||
1923 | switch (workaround) | |
1924 | { | |
1925 | case NONE: | |
1926 | break; | |
1927 | ||
1928 | case ALIGN4: | |
1929 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1930 | _("Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
1931 | unit->dwarf_frame_section->owner->filename, |
1932 | unit->dwarf_frame_section->name); | |
1933 | break; | |
1934 | ||
1935 | case ALIGN8: | |
1936 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1937 | _("Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
1938 | unit->dwarf_frame_section->owner->filename, |
1939 | unit->dwarf_frame_section->name); | |
1940 | break; | |
1941 | ||
1942 | default: | |
1943 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1944 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
1945 | unit->dwarf_frame_section->owner->filename, |
1946 | unit->dwarf_frame_section->name); | |
1947 | break; | |
1948 | } | |
1949 | ||
1950 | return ret; | |
1951 | } | |
cfc14b3a MK |
1952 | \f |
1953 | ||
1954 | /* FIXME: kettenis/20030504: This still needs to be integrated with | |
1955 | dwarf2read.c in a better way. */ | |
1956 | ||
1957 | /* Imported from dwarf2read.c. */ | |
cfc14b3a | 1958 | extern asection *dwarf_frame_section; |
cfc14b3a MK |
1959 | extern asection *dwarf_eh_frame_section; |
1960 | ||
1961 | /* Imported from dwarf2read.c. */ | |
1193688d | 1962 | extern gdb_byte *dwarf2_read_section (struct objfile *objfile, asection *sectp); |
cfc14b3a MK |
1963 | |
1964 | void | |
1965 | dwarf2_build_frame_info (struct objfile *objfile) | |
1966 | { | |
1967 | struct comp_unit unit; | |
852483bc | 1968 | gdb_byte *frame_ptr; |
cfc14b3a MK |
1969 | |
1970 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
1971 | unit.abfd = objfile->obfd; | |
1972 | unit.objfile = objfile; | |
0912c7f2 | 1973 | unit.dbase = 0; |
0fd85043 | 1974 | unit.tbase = 0; |
cfc14b3a MK |
1975 | |
1976 | /* First add the information from the .eh_frame section. That way, | |
1977 | the FDEs from that section are searched last. */ | |
188dd5d6 | 1978 | if (dwarf_eh_frame_section) |
cfc14b3a | 1979 | { |
0fd85043 | 1980 | asection *got, *txt; |
0912c7f2 | 1981 | |
cfc14b3a MK |
1982 | unit.cie = NULL; |
1983 | unit.dwarf_frame_buffer = dwarf2_read_section (objfile, | |
cfc14b3a MK |
1984 | dwarf_eh_frame_section); |
1985 | ||
2c500098 | 1986 | unit.dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section); |
cfc14b3a MK |
1987 | unit.dwarf_frame_section = dwarf_eh_frame_section; |
1988 | ||
0912c7f2 | 1989 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base |
37b517aa MK |
1990 | that is used for the i386/amd64 target, which currently is |
1991 | the only target in GCC that supports/uses the | |
1992 | DW_EH_PE_datarel encoding. */ | |
0912c7f2 MK |
1993 | got = bfd_get_section_by_name (unit.abfd, ".got"); |
1994 | if (got) | |
1995 | unit.dbase = got->vma; | |
1996 | ||
22c7ba1a MK |
1997 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 |
1998 | so far. */ | |
0fd85043 CV |
1999 | txt = bfd_get_section_by_name (unit.abfd, ".text"); |
2000 | if (txt) | |
2001 | unit.tbase = txt->vma; | |
2002 | ||
cfc14b3a MK |
2003 | frame_ptr = unit.dwarf_frame_buffer; |
2004 | while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) | |
2005 | frame_ptr = decode_frame_entry (&unit, frame_ptr, 1); | |
2006 | } | |
2007 | ||
188dd5d6 | 2008 | if (dwarf_frame_section) |
cfc14b3a MK |
2009 | { |
2010 | unit.cie = NULL; | |
2011 | unit.dwarf_frame_buffer = dwarf2_read_section (objfile, | |
cfc14b3a | 2012 | dwarf_frame_section); |
2c500098 | 2013 | unit.dwarf_frame_size = bfd_get_section_size (dwarf_frame_section); |
cfc14b3a MK |
2014 | unit.dwarf_frame_section = dwarf_frame_section; |
2015 | ||
2016 | frame_ptr = unit.dwarf_frame_buffer; | |
2017 | while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) | |
2018 | frame_ptr = decode_frame_entry (&unit, frame_ptr, 0); | |
2019 | } | |
2020 | } | |
0d0e1a63 MK |
2021 | |
2022 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
2023 | void _initialize_dwarf2_frame (void); | |
2024 | ||
2025 | void | |
2026 | _initialize_dwarf2_frame (void) | |
2027 | { | |
030f20e1 | 2028 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2029 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 2030 | } |