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 | |
11 | the Free Software Foundation; either version 2 of the License, or | |
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 | |
20 | along with this program; if not, write to the Free Software | |
197e01b6 EZ |
21 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
22 | Boston, MA 02110-1301, USA. */ | |
cfc14b3a MK |
23 | |
24 | #include "defs.h" | |
25 | #include "dwarf2expr.h" | |
26 | #include "elf/dwarf2.h" | |
27 | #include "frame.h" | |
28 | #include "frame-base.h" | |
29 | #include "frame-unwind.h" | |
30 | #include "gdbcore.h" | |
31 | #include "gdbtypes.h" | |
32 | #include "symtab.h" | |
33 | #include "objfiles.h" | |
34 | #include "regcache.h" | |
f2da6b3a | 35 | #include "value.h" |
cfc14b3a MK |
36 | |
37 | #include "gdb_assert.h" | |
38 | #include "gdb_string.h" | |
39 | ||
6896c0c7 | 40 | #include "complaints.h" |
cfc14b3a MK |
41 | #include "dwarf2-frame.h" |
42 | ||
43 | /* Call Frame Information (CFI). */ | |
44 | ||
45 | /* Common Information Entry (CIE). */ | |
46 | ||
47 | struct dwarf2_cie | |
48 | { | |
49 | /* Offset into the .debug_frame section where this CIE was found. | |
50 | Used to identify this CIE. */ | |
51 | ULONGEST cie_pointer; | |
52 | ||
53 | /* Constant that is factored out of all advance location | |
54 | instructions. */ | |
55 | ULONGEST code_alignment_factor; | |
56 | ||
57 | /* Constants that is factored out of all offset instructions. */ | |
58 | LONGEST data_alignment_factor; | |
59 | ||
60 | /* Return address column. */ | |
61 | ULONGEST return_address_register; | |
62 | ||
63 | /* Instruction sequence to initialize a register set. */ | |
852483bc MK |
64 | gdb_byte *initial_instructions; |
65 | gdb_byte *end; | |
cfc14b3a | 66 | |
303b6f5d DJ |
67 | /* Saved augmentation, in case it's needed later. */ |
68 | char *augmentation; | |
69 | ||
cfc14b3a | 70 | /* Encoding of addresses. */ |
852483bc | 71 | gdb_byte encoding; |
cfc14b3a | 72 | |
7131cb6e RH |
73 | /* True if a 'z' augmentation existed. */ |
74 | unsigned char saw_z_augmentation; | |
75 | ||
56c987f6 AO |
76 | /* True if an 'S' augmentation existed. */ |
77 | unsigned char signal_frame; | |
78 | ||
303b6f5d DJ |
79 | /* The version recorded in the CIE. */ |
80 | unsigned char version; | |
81 | ||
cfc14b3a MK |
82 | struct dwarf2_cie *next; |
83 | }; | |
84 | ||
85 | /* Frame Description Entry (FDE). */ | |
86 | ||
87 | struct dwarf2_fde | |
88 | { | |
89 | /* CIE for this FDE. */ | |
90 | struct dwarf2_cie *cie; | |
91 | ||
92 | /* First location associated with this FDE. */ | |
93 | CORE_ADDR initial_location; | |
94 | ||
95 | /* Number of bytes of program instructions described by this FDE. */ | |
96 | CORE_ADDR address_range; | |
97 | ||
98 | /* Instruction sequence. */ | |
852483bc MK |
99 | gdb_byte *instructions; |
100 | gdb_byte *end; | |
cfc14b3a | 101 | |
4bf8967c AS |
102 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
103 | section. */ | |
104 | unsigned char eh_frame_p; | |
105 | ||
cfc14b3a MK |
106 | struct dwarf2_fde *next; |
107 | }; | |
108 | ||
109 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc); | |
4fc771b8 DJ |
110 | |
111 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
112 | int eh_frame_p); | |
cfc14b3a MK |
113 | \f |
114 | ||
115 | /* Structure describing a frame state. */ | |
116 | ||
117 | struct dwarf2_frame_state | |
118 | { | |
119 | /* Each register save state can be described in terms of a CFA slot, | |
120 | another register, or a location expression. */ | |
121 | struct dwarf2_frame_state_reg_info | |
122 | { | |
05cbe71a | 123 | struct dwarf2_frame_state_reg *reg; |
cfc14b3a MK |
124 | int num_regs; |
125 | ||
126 | /* Used to implement DW_CFA_remember_state. */ | |
127 | struct dwarf2_frame_state_reg_info *prev; | |
128 | } regs; | |
129 | ||
130 | LONGEST cfa_offset; | |
131 | ULONGEST cfa_reg; | |
852483bc | 132 | gdb_byte *cfa_exp; |
cfc14b3a MK |
133 | enum { |
134 | CFA_UNSET, | |
135 | CFA_REG_OFFSET, | |
136 | CFA_EXP | |
137 | } cfa_how; | |
138 | ||
139 | /* The PC described by the current frame state. */ | |
140 | CORE_ADDR pc; | |
141 | ||
142 | /* Initial register set from the CIE. | |
143 | Used to implement DW_CFA_restore. */ | |
144 | struct dwarf2_frame_state_reg_info initial; | |
145 | ||
146 | /* The information we care about from the CIE. */ | |
147 | LONGEST data_align; | |
148 | ULONGEST code_align; | |
149 | ULONGEST retaddr_column; | |
303b6f5d DJ |
150 | |
151 | /* Flags for known producer quirks. */ | |
152 | ||
153 | /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa | |
154 | and DW_CFA_def_cfa_offset takes a factored offset. */ | |
155 | int armcc_cfa_offsets_sf; | |
156 | ||
157 | /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that | |
158 | the CFA is defined as REG - OFFSET rather than REG + OFFSET. */ | |
159 | int armcc_cfa_offsets_reversed; | |
cfc14b3a MK |
160 | }; |
161 | ||
162 | /* Store the length the expression for the CFA in the `cfa_reg' field, | |
163 | which is unused in that case. */ | |
164 | #define cfa_exp_len cfa_reg | |
165 | ||
166 | /* Assert that the register set RS is large enough to store NUM_REGS | |
167 | columns. If necessary, enlarge the register set. */ | |
168 | ||
169 | static void | |
170 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, | |
171 | int num_regs) | |
172 | { | |
173 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
174 | ||
175 | if (num_regs <= rs->num_regs) | |
176 | return; | |
177 | ||
178 | rs->reg = (struct dwarf2_frame_state_reg *) | |
179 | xrealloc (rs->reg, num_regs * size); | |
180 | ||
181 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 182 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
183 | rs->num_regs = num_regs; |
184 | } | |
185 | ||
186 | /* Copy the register columns in register set RS into newly allocated | |
187 | memory and return a pointer to this newly created copy. */ | |
188 | ||
189 | static struct dwarf2_frame_state_reg * | |
190 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
191 | { | |
d10891d4 | 192 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
193 | struct dwarf2_frame_state_reg *reg; |
194 | ||
195 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
196 | memcpy (reg, rs->reg, size); | |
197 | ||
198 | return reg; | |
199 | } | |
200 | ||
201 | /* Release the memory allocated to register set RS. */ | |
202 | ||
203 | static void | |
204 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
205 | { | |
206 | if (rs) | |
207 | { | |
208 | dwarf2_frame_state_free_regs (rs->prev); | |
209 | ||
210 | xfree (rs->reg); | |
211 | xfree (rs); | |
212 | } | |
213 | } | |
214 | ||
215 | /* Release the memory allocated to the frame state FS. */ | |
216 | ||
217 | static void | |
218 | dwarf2_frame_state_free (void *p) | |
219 | { | |
220 | struct dwarf2_frame_state *fs = p; | |
221 | ||
222 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
223 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
224 | xfree (fs->initial.reg); | |
225 | xfree (fs->regs.reg); | |
226 | xfree (fs); | |
227 | } | |
228 | \f | |
229 | ||
230 | /* Helper functions for execute_stack_op. */ | |
231 | ||
232 | static CORE_ADDR | |
233 | read_reg (void *baton, int reg) | |
234 | { | |
235 | struct frame_info *next_frame = (struct frame_info *) baton; | |
05cbe71a | 236 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a | 237 | int regnum; |
852483bc | 238 | gdb_byte *buf; |
cfc14b3a MK |
239 | |
240 | regnum = DWARF2_REG_TO_REGNUM (reg); | |
241 | ||
852483bc | 242 | buf = alloca (register_size (gdbarch, regnum)); |
cfc14b3a | 243 | frame_unwind_register (next_frame, regnum, buf); |
f2da6b3a DJ |
244 | |
245 | /* Convert the register to an integer. This returns a LONGEST | |
246 | rather than a CORE_ADDR, but unpack_pointer does the same thing | |
247 | under the covers, and this makes more sense for non-pointer | |
248 | registers. Maybe read_reg and the associated interfaces should | |
249 | deal with "struct value" instead of CORE_ADDR. */ | |
250 | return unpack_long (register_type (gdbarch, regnum), buf); | |
cfc14b3a MK |
251 | } |
252 | ||
253 | static void | |
852483bc | 254 | read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
cfc14b3a MK |
255 | { |
256 | read_memory (addr, buf, len); | |
257 | } | |
258 | ||
259 | static void | |
852483bc | 260 | no_get_frame_base (void *baton, gdb_byte **start, size_t *length) |
cfc14b3a MK |
261 | { |
262 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 263 | _("Support for DW_OP_fbreg is unimplemented")); |
cfc14b3a MK |
264 | } |
265 | ||
266 | static CORE_ADDR | |
267 | no_get_tls_address (void *baton, CORE_ADDR offset) | |
268 | { | |
269 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 270 | _("Support for DW_OP_GNU_push_tls_address is unimplemented")); |
cfc14b3a MK |
271 | } |
272 | ||
273 | static CORE_ADDR | |
852483bc | 274 | execute_stack_op (gdb_byte *exp, ULONGEST len, |
cfc14b3a MK |
275 | struct frame_info *next_frame, CORE_ADDR initial) |
276 | { | |
277 | struct dwarf_expr_context *ctx; | |
278 | CORE_ADDR result; | |
279 | ||
280 | ctx = new_dwarf_expr_context (); | |
281 | ctx->baton = next_frame; | |
282 | ctx->read_reg = read_reg; | |
283 | ctx->read_mem = read_mem; | |
284 | ctx->get_frame_base = no_get_frame_base; | |
285 | ctx->get_tls_address = no_get_tls_address; | |
286 | ||
287 | dwarf_expr_push (ctx, initial); | |
288 | dwarf_expr_eval (ctx, exp, len); | |
289 | result = dwarf_expr_fetch (ctx, 0); | |
290 | ||
291 | if (ctx->in_reg) | |
292 | result = read_reg (next_frame, result); | |
293 | ||
294 | free_dwarf_expr_context (ctx); | |
295 | ||
296 | return result; | |
297 | } | |
298 | \f | |
299 | ||
300 | static void | |
852483bc | 301 | execute_cfa_program (gdb_byte *insn_ptr, gdb_byte *insn_end, |
cfc14b3a | 302 | struct frame_info *next_frame, |
4bf8967c | 303 | struct dwarf2_frame_state *fs, int eh_frame_p) |
cfc14b3a MK |
304 | { |
305 | CORE_ADDR pc = frame_pc_unwind (next_frame); | |
306 | int bytes_read; | |
4bf8967c | 307 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a MK |
308 | |
309 | while (insn_ptr < insn_end && fs->pc <= pc) | |
310 | { | |
852483bc | 311 | gdb_byte insn = *insn_ptr++; |
cfc14b3a MK |
312 | ULONGEST utmp, reg; |
313 | LONGEST offset; | |
314 | ||
315 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
316 | fs->pc += (insn & 0x3f) * fs->code_align; | |
317 | else if ((insn & 0xc0) == DW_CFA_offset) | |
318 | { | |
319 | reg = insn & 0x3f; | |
4fc771b8 | 320 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
321 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
322 | offset = utmp * fs->data_align; | |
323 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 324 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
325 | fs->regs.reg[reg].loc.offset = offset; |
326 | } | |
327 | else if ((insn & 0xc0) == DW_CFA_restore) | |
328 | { | |
329 | gdb_assert (fs->initial.reg); | |
330 | reg = insn & 0x3f; | |
4fc771b8 | 331 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 332 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
92ad9f6b FR |
333 | if (reg < fs->initial.num_regs) |
334 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
335 | else | |
336 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
337 | ||
338 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
339 | complaint (&symfile_complaints, _("\ | |
340 | incomplete CFI data; DW_CFA_restore unspecified\n\ | |
341 | register %s (#%d) at 0x%s"), | |
342 | REGISTER_NAME(DWARF2_REG_TO_REGNUM(reg)), | |
343 | DWARF2_REG_TO_REGNUM(reg), paddr (fs->pc)); | |
cfc14b3a MK |
344 | } |
345 | else | |
346 | { | |
347 | switch (insn) | |
348 | { | |
349 | case DW_CFA_set_loc: | |
350 | fs->pc = dwarf2_read_address (insn_ptr, insn_end, &bytes_read); | |
351 | insn_ptr += bytes_read; | |
352 | break; | |
353 | ||
354 | case DW_CFA_advance_loc1: | |
355 | utmp = extract_unsigned_integer (insn_ptr, 1); | |
356 | fs->pc += utmp * fs->code_align; | |
357 | insn_ptr++; | |
358 | break; | |
359 | case DW_CFA_advance_loc2: | |
360 | utmp = extract_unsigned_integer (insn_ptr, 2); | |
361 | fs->pc += utmp * fs->code_align; | |
362 | insn_ptr += 2; | |
363 | break; | |
364 | case DW_CFA_advance_loc4: | |
365 | utmp = extract_unsigned_integer (insn_ptr, 4); | |
366 | fs->pc += utmp * fs->code_align; | |
367 | insn_ptr += 4; | |
368 | break; | |
369 | ||
370 | case DW_CFA_offset_extended: | |
371 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 372 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
373 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
374 | offset = utmp * fs->data_align; | |
375 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 376 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
377 | fs->regs.reg[reg].loc.offset = offset; |
378 | break; | |
379 | ||
380 | case DW_CFA_restore_extended: | |
381 | gdb_assert (fs->initial.reg); | |
382 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 383 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
384 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
385 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
386 | break; | |
387 | ||
388 | case DW_CFA_undefined: | |
389 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 390 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 391 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 392 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
393 | break; |
394 | ||
395 | case DW_CFA_same_value: | |
396 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 397 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 398 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 399 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
400 | break; |
401 | ||
402 | case DW_CFA_register: | |
403 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 404 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 405 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 406 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 407 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 408 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
409 | fs->regs.reg[reg].loc.reg = utmp; |
410 | break; | |
411 | ||
412 | case DW_CFA_remember_state: | |
413 | { | |
414 | struct dwarf2_frame_state_reg_info *new_rs; | |
415 | ||
416 | new_rs = XMALLOC (struct dwarf2_frame_state_reg_info); | |
417 | *new_rs = fs->regs; | |
418 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
419 | fs->regs.prev = new_rs; | |
420 | } | |
421 | break; | |
422 | ||
423 | case DW_CFA_restore_state: | |
424 | { | |
425 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
426 | ||
50ea7769 MK |
427 | if (old_rs == NULL) |
428 | { | |
e2e0b3e5 AC |
429 | complaint (&symfile_complaints, _("\ |
430 | bad CFI data; mismatched DW_CFA_restore_state at 0x%s"), paddr (fs->pc)); | |
50ea7769 MK |
431 | } |
432 | else | |
433 | { | |
434 | xfree (fs->regs.reg); | |
435 | fs->regs = *old_rs; | |
436 | xfree (old_rs); | |
437 | } | |
cfc14b3a MK |
438 | } |
439 | break; | |
440 | ||
441 | case DW_CFA_def_cfa: | |
442 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
443 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
444 | |
445 | if (fs->armcc_cfa_offsets_sf) | |
446 | utmp *= fs->data_align; | |
447 | ||
cfc14b3a MK |
448 | fs->cfa_offset = utmp; |
449 | fs->cfa_how = CFA_REG_OFFSET; | |
450 | break; | |
451 | ||
452 | case DW_CFA_def_cfa_register: | |
453 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
454 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
455 | eh_frame_p); | |
cfc14b3a MK |
456 | fs->cfa_how = CFA_REG_OFFSET; |
457 | break; | |
458 | ||
459 | case DW_CFA_def_cfa_offset: | |
852483bc | 460 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
461 | |
462 | if (fs->armcc_cfa_offsets_sf) | |
463 | utmp *= fs->data_align; | |
464 | ||
852483bc | 465 | fs->cfa_offset = utmp; |
cfc14b3a MK |
466 | /* cfa_how deliberately not set. */ |
467 | break; | |
468 | ||
a8504492 MK |
469 | case DW_CFA_nop: |
470 | break; | |
471 | ||
cfc14b3a MK |
472 | case DW_CFA_def_cfa_expression: |
473 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_exp_len); | |
474 | fs->cfa_exp = insn_ptr; | |
475 | fs->cfa_how = CFA_EXP; | |
476 | insn_ptr += fs->cfa_exp_len; | |
477 | break; | |
478 | ||
479 | case DW_CFA_expression: | |
480 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 481 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
482 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
483 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
484 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
485 | fs->regs.reg[reg].exp_len = utmp; | |
05cbe71a | 486 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
487 | insn_ptr += utmp; |
488 | break; | |
489 | ||
a8504492 MK |
490 | case DW_CFA_offset_extended_sf: |
491 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 492 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
a8504492 | 493 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 494 | offset *= fs->data_align; |
a8504492 | 495 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 496 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
497 | fs->regs.reg[reg].loc.offset = offset; |
498 | break; | |
499 | ||
46ea248b AO |
500 | case DW_CFA_val_offset: |
501 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
502 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
503 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
504 | offset = utmp * fs->data_align; | |
505 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
506 | fs->regs.reg[reg].loc.offset = offset; | |
507 | break; | |
508 | ||
509 | case DW_CFA_val_offset_sf: | |
510 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
511 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
512 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
513 | offset *= fs->data_align; | |
514 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
515 | fs->regs.reg[reg].loc.offset = offset; | |
516 | break; | |
517 | ||
518 | case DW_CFA_val_expression: | |
519 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
520 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
521 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
522 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
523 | fs->regs.reg[reg].exp_len = utmp; | |
524 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; | |
525 | insn_ptr += utmp; | |
526 | break; | |
527 | ||
a8504492 MK |
528 | case DW_CFA_def_cfa_sf: |
529 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
530 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
531 | eh_frame_p); | |
a8504492 MK |
532 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
533 | fs->cfa_offset = offset * fs->data_align; | |
534 | fs->cfa_how = CFA_REG_OFFSET; | |
535 | break; | |
536 | ||
537 | case DW_CFA_def_cfa_offset_sf: | |
538 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
539 | fs->cfa_offset = offset * fs->data_align; | |
540 | /* cfa_how deliberately not set. */ | |
cfc14b3a MK |
541 | break; |
542 | ||
a77f4086 MK |
543 | case DW_CFA_GNU_window_save: |
544 | /* This is SPARC-specific code, and contains hard-coded | |
545 | constants for the register numbering scheme used by | |
546 | GCC. Rather than having a architecture-specific | |
547 | operation that's only ever used by a single | |
548 | architecture, we provide the implementation here. | |
549 | Incidentally that's what GCC does too in its | |
550 | unwinder. */ | |
551 | { | |
552 | struct gdbarch *gdbarch = get_frame_arch (next_frame); | |
553 | int size = register_size(gdbarch, 0); | |
554 | dwarf2_frame_state_alloc_regs (&fs->regs, 32); | |
555 | for (reg = 8; reg < 16; reg++) | |
556 | { | |
557 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; | |
558 | fs->regs.reg[reg].loc.reg = reg + 16; | |
559 | } | |
560 | for (reg = 16; reg < 32; reg++) | |
561 | { | |
562 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
563 | fs->regs.reg[reg].loc.offset = (reg - 16) * size; | |
564 | } | |
565 | } | |
566 | break; | |
567 | ||
cfc14b3a MK |
568 | case DW_CFA_GNU_args_size: |
569 | /* Ignored. */ | |
570 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
571 | break; | |
572 | ||
58894217 JK |
573 | case DW_CFA_GNU_negative_offset_extended: |
574 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 575 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
58894217 JK |
576 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset); |
577 | offset *= fs->data_align; | |
578 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
579 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
580 | fs->regs.reg[reg].loc.offset = -offset; | |
581 | break; | |
582 | ||
cfc14b3a | 583 | default: |
e2e0b3e5 | 584 | internal_error (__FILE__, __LINE__, _("Unknown CFI encountered.")); |
cfc14b3a MK |
585 | } |
586 | } | |
587 | } | |
588 | ||
589 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
590 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
591 | fs->regs.prev = NULL; | |
592 | } | |
8f22cb90 | 593 | \f |
cfc14b3a | 594 | |
8f22cb90 | 595 | /* Architecture-specific operations. */ |
cfc14b3a | 596 | |
8f22cb90 MK |
597 | /* Per-architecture data key. */ |
598 | static struct gdbarch_data *dwarf2_frame_data; | |
599 | ||
600 | struct dwarf2_frame_ops | |
601 | { | |
602 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
603 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
604 | struct frame_info *); | |
3ed09a32 DJ |
605 | |
606 | /* Check whether the frame preceding NEXT_FRAME will be a signal | |
607 | trampoline. */ | |
608 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); | |
4bf8967c | 609 | |
4fc771b8 DJ |
610 | /* Convert .eh_frame register number to DWARF register number, or |
611 | adjust .debug_frame register number. */ | |
612 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
613 | }; |
614 | ||
8f22cb90 MK |
615 | /* Default architecture-specific register state initialization |
616 | function. */ | |
617 | ||
618 | static void | |
619 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 DM |
620 | struct dwarf2_frame_state_reg *reg, |
621 | struct frame_info *next_frame) | |
8f22cb90 MK |
622 | { |
623 | /* If we have a register that acts as a program counter, mark it as | |
624 | a destination for the return address. If we have a register that | |
625 | serves as the stack pointer, arrange for it to be filled with the | |
626 | call frame address (CFA). The other registers are marked as | |
627 | unspecified. | |
628 | ||
629 | We copy the return address to the program counter, since many | |
630 | parts in GDB assume that it is possible to get the return address | |
631 | by unwinding the program counter register. However, on ISA's | |
632 | with a dedicated return address register, the CFI usually only | |
633 | contains information to unwind that return address register. | |
634 | ||
635 | The reason we're treating the stack pointer special here is | |
636 | because in many cases GCC doesn't emit CFI for the stack pointer | |
637 | and implicitly assumes that it is equal to the CFA. This makes | |
638 | some sense since the DWARF specification (version 3, draft 8, | |
639 | p. 102) says that: | |
640 | ||
641 | "Typically, the CFA is defined to be the value of the stack | |
642 | pointer at the call site in the previous frame (which may be | |
643 | different from its value on entry to the current frame)." | |
644 | ||
645 | However, this isn't true for all platforms supported by GCC | |
646 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
647 | their own architecture-specific initialization function. */ | |
05cbe71a | 648 | |
8f22cb90 MK |
649 | if (regnum == PC_REGNUM) |
650 | reg->how = DWARF2_FRAME_REG_RA; | |
651 | else if (regnum == SP_REGNUM) | |
652 | reg->how = DWARF2_FRAME_REG_CFA; | |
653 | } | |
05cbe71a | 654 | |
8f22cb90 | 655 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 656 | |
8f22cb90 | 657 | static void * |
030f20e1 | 658 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
659 | { |
660 | struct dwarf2_frame_ops *ops; | |
661 | ||
030f20e1 | 662 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
663 | ops->init_reg = dwarf2_frame_default_init_reg; |
664 | return ops; | |
665 | } | |
05cbe71a | 666 | |
8f22cb90 MK |
667 | /* Set the architecture-specific register state initialization |
668 | function for GDBARCH to INIT_REG. */ | |
669 | ||
670 | void | |
671 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
672 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
673 | struct dwarf2_frame_state_reg *, |
674 | struct frame_info *)) | |
8f22cb90 | 675 | { |
030f20e1 | 676 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 677 | |
8f22cb90 MK |
678 | ops->init_reg = init_reg; |
679 | } | |
680 | ||
681 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
682 | |
683 | static void | |
684 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 DM |
685 | struct dwarf2_frame_state_reg *reg, |
686 | struct frame_info *next_frame) | |
05cbe71a | 687 | { |
030f20e1 | 688 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 689 | |
aff37fc1 | 690 | ops->init_reg (gdbarch, regnum, reg, next_frame); |
05cbe71a | 691 | } |
3ed09a32 DJ |
692 | |
693 | /* Set the architecture-specific signal trampoline recognition | |
694 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
695 | ||
696 | void | |
697 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
698 | int (*signal_frame_p) (struct gdbarch *, | |
699 | struct frame_info *)) | |
700 | { | |
701 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
702 | ||
703 | ops->signal_frame_p = signal_frame_p; | |
704 | } | |
705 | ||
706 | /* Query the architecture-specific signal frame recognizer for | |
707 | NEXT_FRAME. */ | |
708 | ||
709 | static int | |
710 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
711 | struct frame_info *next_frame) | |
712 | { | |
713 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
714 | ||
715 | if (ops->signal_frame_p == NULL) | |
716 | return 0; | |
717 | return ops->signal_frame_p (gdbarch, next_frame); | |
718 | } | |
4bf8967c | 719 | |
4fc771b8 DJ |
720 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
721 | register numbers. */ | |
4bf8967c AS |
722 | |
723 | void | |
4fc771b8 DJ |
724 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
725 | int (*adjust_regnum) (struct gdbarch *, | |
726 | int, int)) | |
4bf8967c AS |
727 | { |
728 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
729 | ||
4fc771b8 | 730 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
731 | } |
732 | ||
4fc771b8 DJ |
733 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
734 | register. */ | |
4bf8967c | 735 | |
4fc771b8 DJ |
736 | static int |
737 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p) | |
4bf8967c AS |
738 | { |
739 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
740 | ||
4fc771b8 | 741 | if (ops->adjust_regnum == NULL) |
4bf8967c | 742 | return regnum; |
4fc771b8 | 743 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 744 | } |
303b6f5d DJ |
745 | |
746 | static void | |
747 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
748 | struct dwarf2_fde *fde) | |
749 | { | |
750 | static const char *arm_idents[] = { | |
751 | "ARM C Compiler, ADS", | |
752 | "Thumb C Compiler, ADS", | |
753 | "ARM C++ Compiler, ADS", | |
754 | "Thumb C++ Compiler, ADS", | |
755 | "ARM/Thumb C/C++ Compiler, RVCT" | |
756 | }; | |
757 | int i; | |
758 | ||
759 | struct symtab *s; | |
760 | ||
761 | s = find_pc_symtab (fs->pc); | |
762 | if (s == NULL || s->producer == NULL) | |
763 | return; | |
764 | ||
765 | for (i = 0; i < ARRAY_SIZE (arm_idents); i++) | |
766 | if (strncmp (s->producer, arm_idents[i], strlen (arm_idents[i])) == 0) | |
767 | { | |
768 | if (fde->cie->version == 1) | |
769 | fs->armcc_cfa_offsets_sf = 1; | |
770 | ||
771 | if (fde->cie->version == 1) | |
772 | fs->armcc_cfa_offsets_reversed = 1; | |
773 | ||
774 | /* The reversed offset problem is present in some compilers | |
775 | using DWARF3, but it was eventually fixed. Check the ARM | |
776 | defined augmentations, which are in the format "armcc" followed | |
777 | by a list of one-character options. The "+" option means | |
778 | this problem is fixed (no quirk needed). If the armcc | |
779 | augmentation is missing, the quirk is needed. */ | |
780 | if (fde->cie->version == 3 | |
781 | && (strncmp (fde->cie->augmentation, "armcc", 5) != 0 | |
782 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) | |
783 | fs->armcc_cfa_offsets_reversed = 1; | |
784 | ||
785 | return; | |
786 | } | |
787 | } | |
8f22cb90 MK |
788 | \f |
789 | ||
790 | struct dwarf2_frame_cache | |
791 | { | |
792 | /* DWARF Call Frame Address. */ | |
793 | CORE_ADDR cfa; | |
794 | ||
0228dfb9 DJ |
795 | /* Set if the return address column was marked as undefined. */ |
796 | int undefined_retaddr; | |
797 | ||
8f22cb90 MK |
798 | /* Saved registers, indexed by GDB register number, not by DWARF |
799 | register number. */ | |
800 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
801 | |
802 | /* Return address register. */ | |
803 | struct dwarf2_frame_state_reg retaddr_reg; | |
8f22cb90 | 804 | }; |
05cbe71a | 805 | |
b9362cc7 | 806 | static struct dwarf2_frame_cache * |
cfc14b3a MK |
807 | dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache) |
808 | { | |
809 | struct cleanup *old_chain; | |
05cbe71a | 810 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
3e2c4033 | 811 | const int num_regs = NUM_REGS + NUM_PSEUDO_REGS; |
cfc14b3a MK |
812 | struct dwarf2_frame_cache *cache; |
813 | struct dwarf2_frame_state *fs; | |
814 | struct dwarf2_fde *fde; | |
cfc14b3a MK |
815 | |
816 | if (*this_cache) | |
817 | return *this_cache; | |
818 | ||
819 | /* Allocate a new cache. */ | |
820 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
821 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
822 | ||
823 | /* Allocate and initialize the frame state. */ | |
824 | fs = XMALLOC (struct dwarf2_frame_state); | |
825 | memset (fs, 0, sizeof (struct dwarf2_frame_state)); | |
826 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); | |
827 | ||
828 | /* Unwind the PC. | |
829 | ||
830 | Note that if NEXT_FRAME is never supposed to return (i.e. a call | |
831 | to abort), the compiler might optimize away the instruction at | |
832 | NEXT_FRAME's return address. As a result the return address will | |
833 | point at some random instruction, and the CFI for that | |
e4e9607c | 834 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
835 | this problem by substracting 1 from the return address to get an |
836 | address in the middle of a presumed call instruction (or the | |
837 | instruction in the associated delay slot). This should only be | |
838 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c MK |
839 | handlers, sentinel frames, dummy frames). The function |
840 | frame_unwind_address_in_block does just this. It's not clear how | |
841 | reliable the method is though; there is the potential for the | |
842 | register state pre-call being different to that on return. */ | |
93d42b30 | 843 | fs->pc = frame_unwind_address_in_block (next_frame, NORMAL_FRAME); |
cfc14b3a MK |
844 | |
845 | /* Find the correct FDE. */ | |
846 | fde = dwarf2_frame_find_fde (&fs->pc); | |
847 | gdb_assert (fde != NULL); | |
848 | ||
849 | /* Extract any interesting information from the CIE. */ | |
850 | fs->data_align = fde->cie->data_alignment_factor; | |
851 | fs->code_align = fde->cie->code_alignment_factor; | |
852 | fs->retaddr_column = fde->cie->return_address_register; | |
853 | ||
303b6f5d DJ |
854 | /* Check for "quirks" - known bugs in producers. */ |
855 | dwarf2_frame_find_quirks (fs, fde); | |
856 | ||
cfc14b3a MK |
857 | /* First decode all the insns in the CIE. */ |
858 | execute_cfa_program (fde->cie->initial_instructions, | |
4bf8967c | 859 | fde->cie->end, next_frame, fs, fde->eh_frame_p); |
cfc14b3a MK |
860 | |
861 | /* Save the initialized register set. */ | |
862 | fs->initial = fs->regs; | |
863 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
864 | ||
865 | /* Then decode the insns in the FDE up to our target PC. */ | |
4bf8967c AS |
866 | execute_cfa_program (fde->instructions, fde->end, next_frame, fs, |
867 | fde->eh_frame_p); | |
cfc14b3a MK |
868 | |
869 | /* Caclulate the CFA. */ | |
870 | switch (fs->cfa_how) | |
871 | { | |
872 | case CFA_REG_OFFSET: | |
873 | cache->cfa = read_reg (next_frame, fs->cfa_reg); | |
303b6f5d DJ |
874 | if (fs->armcc_cfa_offsets_reversed) |
875 | cache->cfa -= fs->cfa_offset; | |
876 | else | |
877 | cache->cfa += fs->cfa_offset; | |
cfc14b3a MK |
878 | break; |
879 | ||
880 | case CFA_EXP: | |
881 | cache->cfa = | |
882 | execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, next_frame, 0); | |
883 | break; | |
884 | ||
885 | default: | |
e2e0b3e5 | 886 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); |
cfc14b3a MK |
887 | } |
888 | ||
05cbe71a | 889 | /* Initialize the register state. */ |
3e2c4033 AC |
890 | { |
891 | int regnum; | |
e4e9607c | 892 | |
3e2c4033 | 893 | for (regnum = 0; regnum < num_regs; regnum++) |
aff37fc1 | 894 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], next_frame); |
3e2c4033 AC |
895 | } |
896 | ||
897 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
898 | location information in the cache. Note that we don't skip the |
899 | return address column; it's perfectly all right for it to | |
900 | correspond to a real register. If it doesn't correspond to a | |
901 | real register, or if we shouldn't treat it as such, | |
902 | DWARF2_REG_TO_REGNUM should be defined to return a number outside | |
903 | the range [0, NUM_REGS). */ | |
3e2c4033 AC |
904 | { |
905 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 906 | |
3e2c4033 AC |
907 | for (column = 0; column < fs->regs.num_regs; column++) |
908 | { | |
3e2c4033 | 909 | /* Use the GDB register number as the destination index. */ |
79c4cb80 | 910 | int regnum = DWARF2_REG_TO_REGNUM (column); |
3e2c4033 AC |
911 | |
912 | /* If there's no corresponding GDB register, ignore it. */ | |
913 | if (regnum < 0 || regnum >= num_regs) | |
914 | continue; | |
915 | ||
916 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
917 | of all debug info registers. If it doesn't, complain (but |
918 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
919 | unspecified register implies "same value" when CFI (draft |
920 | 7) specifies nothing at all. Such a register could equally | |
921 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
922 | isn't sufficient; it only checks that all registers in the |
923 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 924 | problems when a debug info register falls outside of the |
e4e9607c | 925 | table. We need a way of iterating through all the valid |
3e2c4033 | 926 | DWARF2 register numbers. */ |
05cbe71a | 927 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
928 | { |
929 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 AC |
930 | complaint (&symfile_complaints, _("\ |
931 | incomplete CFI data; unspecified registers (e.g., %s) at 0x%s"), | |
f059bf6f AC |
932 | gdbarch_register_name (gdbarch, regnum), |
933 | paddr_nz (fs->pc)); | |
934 | } | |
35889917 MK |
935 | else |
936 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
937 | } |
938 | } | |
cfc14b3a | 939 | |
8d5a9abc MK |
940 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
941 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
942 | { |
943 | int regnum; | |
944 | ||
945 | for (regnum = 0; regnum < num_regs; regnum++) | |
946 | { | |
8d5a9abc MK |
947 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
948 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 949 | { |
05cbe71a MK |
950 | struct dwarf2_frame_state_reg *retaddr_reg = |
951 | &fs->regs.reg[fs->retaddr_column]; | |
952 | ||
d4f10bf2 MK |
953 | /* It seems rather bizarre to specify an "empty" column as |
954 | the return adress column. However, this is exactly | |
955 | what GCC does on some targets. It turns out that GCC | |
956 | assumes that the return address can be found in the | |
957 | register corresponding to the return address column. | |
8d5a9abc MK |
958 | Incidentally, that's how we should treat a return |
959 | address column specifying "same value" too. */ | |
d4f10bf2 | 960 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
961 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
962 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
963 | { |
964 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
965 | cache->reg[regnum] = *retaddr_reg; | |
966 | else | |
967 | cache->retaddr_reg = *retaddr_reg; | |
968 | } | |
35889917 MK |
969 | else |
970 | { | |
8d5a9abc MK |
971 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
972 | { | |
973 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
974 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
975 | } | |
976 | else | |
977 | { | |
978 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
979 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
980 | } | |
35889917 MK |
981 | } |
982 | } | |
983 | } | |
984 | } | |
cfc14b3a | 985 | |
0228dfb9 DJ |
986 | if (fs->retaddr_column < fs->regs.num_regs |
987 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
988 | cache->undefined_retaddr = 1; | |
989 | ||
cfc14b3a MK |
990 | do_cleanups (old_chain); |
991 | ||
992 | *this_cache = cache; | |
993 | return cache; | |
994 | } | |
995 | ||
996 | static void | |
997 | dwarf2_frame_this_id (struct frame_info *next_frame, void **this_cache, | |
998 | struct frame_id *this_id) | |
999 | { | |
1000 | struct dwarf2_frame_cache *cache = | |
1001 | dwarf2_frame_cache (next_frame, this_cache); | |
1002 | ||
0228dfb9 DJ |
1003 | if (cache->undefined_retaddr) |
1004 | return; | |
1005 | ||
93d42b30 DJ |
1006 | (*this_id) = frame_id_build (cache->cfa, |
1007 | frame_func_unwind (next_frame, NORMAL_FRAME)); | |
1008 | } | |
1009 | ||
1010 | static void | |
1011 | dwarf2_signal_frame_this_id (struct frame_info *next_frame, void **this_cache, | |
1012 | struct frame_id *this_id) | |
1013 | { | |
1014 | struct dwarf2_frame_cache *cache = | |
1015 | dwarf2_frame_cache (next_frame, this_cache); | |
1016 | ||
1017 | if (cache->undefined_retaddr) | |
1018 | return; | |
1019 | ||
1020 | (*this_id) = frame_id_build (cache->cfa, | |
1021 | frame_func_unwind (next_frame, SIGTRAMP_FRAME)); | |
cfc14b3a MK |
1022 | } |
1023 | ||
1024 | static void | |
1025 | dwarf2_frame_prev_register (struct frame_info *next_frame, void **this_cache, | |
1026 | int regnum, int *optimizedp, | |
1027 | enum lval_type *lvalp, CORE_ADDR *addrp, | |
c6826062 | 1028 | int *realnump, gdb_byte *valuep) |
cfc14b3a | 1029 | { |
05cbe71a | 1030 | struct gdbarch *gdbarch = get_frame_arch (next_frame); |
cfc14b3a MK |
1031 | struct dwarf2_frame_cache *cache = |
1032 | dwarf2_frame_cache (next_frame, this_cache); | |
1033 | ||
1034 | switch (cache->reg[regnum].how) | |
1035 | { | |
05cbe71a | 1036 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1037 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1038 | mark it as optimized away; the value isn't available. */ |
cfc14b3a MK |
1039 | *optimizedp = 1; |
1040 | *lvalp = not_lval; | |
1041 | *addrp = 0; | |
1042 | *realnump = -1; | |
35889917 | 1043 | if (valuep) |
cfc14b3a MK |
1044 | { |
1045 | /* In some cases, for example %eflags on the i386, we have | |
1046 | to provide a sane value, even though this register wasn't | |
1047 | saved. Assume we can get it from NEXT_FRAME. */ | |
1048 | frame_unwind_register (next_frame, regnum, valuep); | |
1049 | } | |
1050 | break; | |
1051 | ||
05cbe71a | 1052 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
cfc14b3a MK |
1053 | *optimizedp = 0; |
1054 | *lvalp = lval_memory; | |
1055 | *addrp = cache->cfa + cache->reg[regnum].loc.offset; | |
1056 | *realnump = -1; | |
1057 | if (valuep) | |
1058 | { | |
1059 | /* Read the value in from memory. */ | |
05cbe71a | 1060 | read_memory (*addrp, valuep, register_size (gdbarch, regnum)); |
cfc14b3a MK |
1061 | } |
1062 | break; | |
1063 | ||
05cbe71a | 1064 | case DWARF2_FRAME_REG_SAVED_REG: |
00b25ff3 AC |
1065 | *optimizedp = 0; |
1066 | *lvalp = lval_register; | |
1067 | *addrp = 0; | |
1068 | *realnump = DWARF2_REG_TO_REGNUM (cache->reg[regnum].loc.reg); | |
1069 | if (valuep) | |
1070 | frame_unwind_register (next_frame, (*realnump), valuep); | |
cfc14b3a MK |
1071 | break; |
1072 | ||
05cbe71a | 1073 | case DWARF2_FRAME_REG_SAVED_EXP: |
cfc14b3a MK |
1074 | *optimizedp = 0; |
1075 | *lvalp = lval_memory; | |
1076 | *addrp = execute_stack_op (cache->reg[regnum].loc.exp, | |
1077 | cache->reg[regnum].exp_len, | |
1078 | next_frame, cache->cfa); | |
1079 | *realnump = -1; | |
1080 | if (valuep) | |
1081 | { | |
1082 | /* Read the value in from memory. */ | |
05cbe71a | 1083 | read_memory (*addrp, valuep, register_size (gdbarch, regnum)); |
cfc14b3a MK |
1084 | } |
1085 | break; | |
1086 | ||
46ea248b AO |
1087 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
1088 | *optimizedp = 0; | |
1089 | *lvalp = not_lval; | |
1090 | *addrp = 0; | |
1091 | *realnump = -1; | |
1092 | if (valuep) | |
1093 | store_unsigned_integer (valuep, register_size (gdbarch, regnum), | |
1094 | cache->cfa + cache->reg[regnum].loc.offset); | |
1095 | break; | |
1096 | ||
1097 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
1098 | *optimizedp = 0; | |
1099 | *lvalp = not_lval; | |
1100 | *addrp = 0; | |
1101 | *realnump = -1; | |
1102 | if (valuep) | |
1103 | store_unsigned_integer (valuep, register_size (gdbarch, regnum), | |
1104 | execute_stack_op (cache->reg[regnum].loc.exp, | |
1105 | cache->reg[regnum].exp_len, | |
1106 | next_frame, cache->cfa)); | |
1107 | break; | |
1108 | ||
05cbe71a | 1109 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1110 | /* GCC, in its infinite wisdom decided to not provide unwind |
1111 | information for registers that are "same value". Since | |
1112 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1113 | registers are actually undefined (which is different to CFI | |
1114 | "undefined"). Code above issues a complaint about this. | |
1115 | Here just fudge the books, assume GCC, and that the value is | |
1116 | more inner on the stack. */ | |
00b25ff3 AC |
1117 | *optimizedp = 0; |
1118 | *lvalp = lval_register; | |
1119 | *addrp = 0; | |
1120 | *realnump = regnum; | |
1121 | if (valuep) | |
1122 | frame_unwind_register (next_frame, (*realnump), valuep); | |
3e2c4033 AC |
1123 | break; |
1124 | ||
05cbe71a | 1125 | case DWARF2_FRAME_REG_SAME_VALUE: |
00b25ff3 AC |
1126 | *optimizedp = 0; |
1127 | *lvalp = lval_register; | |
1128 | *addrp = 0; | |
1129 | *realnump = regnum; | |
1130 | if (valuep) | |
1131 | frame_unwind_register (next_frame, (*realnump), valuep); | |
cfc14b3a MK |
1132 | break; |
1133 | ||
05cbe71a | 1134 | case DWARF2_FRAME_REG_CFA: |
35889917 MK |
1135 | *optimizedp = 0; |
1136 | *lvalp = not_lval; | |
1137 | *addrp = 0; | |
1138 | *realnump = -1; | |
1139 | if (valuep) | |
14d06750 | 1140 | pack_long (valuep, register_type (gdbarch, regnum), cache->cfa); |
35889917 MK |
1141 | break; |
1142 | ||
ea7963f0 FR |
1143 | case DWARF2_FRAME_REG_CFA_OFFSET: |
1144 | *optimizedp = 0; | |
1145 | *lvalp = not_lval; | |
1146 | *addrp = 0; | |
1147 | *realnump = -1; | |
1148 | if (valuep) | |
14d06750 DJ |
1149 | pack_long (valuep, register_type (gdbarch, regnum), |
1150 | cache->cfa + cache->reg[regnum].loc.offset); | |
ea7963f0 FR |
1151 | break; |
1152 | ||
8d5a9abc MK |
1153 | case DWARF2_FRAME_REG_RA_OFFSET: |
1154 | *optimizedp = 0; | |
1155 | *lvalp = not_lval; | |
1156 | *addrp = 0; | |
1157 | *realnump = -1; | |
1158 | if (valuep) | |
1159 | { | |
1160 | CORE_ADDR pc = cache->reg[regnum].loc.offset; | |
1161 | ||
1162 | regnum = DWARF2_REG_TO_REGNUM (cache->retaddr_reg.loc.reg); | |
1163 | pc += frame_unwind_register_unsigned (next_frame, regnum); | |
14d06750 | 1164 | pack_long (valuep, register_type (gdbarch, regnum), pc); |
8d5a9abc MK |
1165 | } |
1166 | break; | |
1167 | ||
cfc14b3a | 1168 | default: |
e2e0b3e5 | 1169 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1170 | } |
1171 | } | |
1172 | ||
1173 | static const struct frame_unwind dwarf2_frame_unwind = | |
1174 | { | |
1175 | NORMAL_FRAME, | |
1176 | dwarf2_frame_this_id, | |
1177 | dwarf2_frame_prev_register | |
1178 | }; | |
1179 | ||
3ed09a32 DJ |
1180 | static const struct frame_unwind dwarf2_signal_frame_unwind = |
1181 | { | |
1182 | SIGTRAMP_FRAME, | |
93d42b30 | 1183 | dwarf2_signal_frame_this_id, |
3ed09a32 DJ |
1184 | dwarf2_frame_prev_register |
1185 | }; | |
1186 | ||
cfc14b3a | 1187 | const struct frame_unwind * |
336d1bba | 1188 | dwarf2_frame_sniffer (struct frame_info *next_frame) |
cfc14b3a | 1189 | { |
1ce5d6dd AC |
1190 | /* Grab an address that is guarenteed to reside somewhere within the |
1191 | function. frame_pc_unwind(), for a no-return next function, can | |
93d42b30 DJ |
1192 | end up returning something past the end of this function's body. |
1193 | If the frame we're sniffing for is a signal frame whose start | |
1194 | address is placed on the stack by the OS, its FDE must | |
1195 | extend one byte before its start address or we will miss it. */ | |
1196 | CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame, | |
1197 | NORMAL_FRAME); | |
56c987f6 AO |
1198 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr); |
1199 | if (!fde) | |
3ed09a32 DJ |
1200 | return NULL; |
1201 | ||
1202 | /* On some targets, signal trampolines may have unwind information. | |
1203 | We need to recognize them so that we set the frame type | |
1204 | correctly. */ | |
1205 | ||
56c987f6 AO |
1206 | if (fde->cie->signal_frame |
1207 | || dwarf2_frame_signal_frame_p (get_frame_arch (next_frame), | |
1208 | next_frame)) | |
3ed09a32 | 1209 | return &dwarf2_signal_frame_unwind; |
cfc14b3a | 1210 | |
3ed09a32 | 1211 | return &dwarf2_frame_unwind; |
cfc14b3a MK |
1212 | } |
1213 | \f | |
1214 | ||
1215 | /* There is no explicitly defined relationship between the CFA and the | |
1216 | location of frame's local variables and arguments/parameters. | |
1217 | Therefore, frame base methods on this page should probably only be | |
1218 | used as a last resort, just to avoid printing total garbage as a | |
1219 | response to the "info frame" command. */ | |
1220 | ||
1221 | static CORE_ADDR | |
1222 | dwarf2_frame_base_address (struct frame_info *next_frame, void **this_cache) | |
1223 | { | |
1224 | struct dwarf2_frame_cache *cache = | |
1225 | dwarf2_frame_cache (next_frame, this_cache); | |
1226 | ||
1227 | return cache->cfa; | |
1228 | } | |
1229 | ||
1230 | static const struct frame_base dwarf2_frame_base = | |
1231 | { | |
1232 | &dwarf2_frame_unwind, | |
1233 | dwarf2_frame_base_address, | |
1234 | dwarf2_frame_base_address, | |
1235 | dwarf2_frame_base_address | |
1236 | }; | |
1237 | ||
1238 | const struct frame_base * | |
336d1bba | 1239 | dwarf2_frame_base_sniffer (struct frame_info *next_frame) |
cfc14b3a | 1240 | { |
93d42b30 DJ |
1241 | CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame, |
1242 | NORMAL_FRAME); | |
1243 | if (dwarf2_frame_find_fde (&block_addr)) | |
cfc14b3a MK |
1244 | return &dwarf2_frame_base; |
1245 | ||
1246 | return NULL; | |
1247 | } | |
1248 | \f | |
1249 | /* A minimal decoding of DWARF2 compilation units. We only decode | |
1250 | what's needed to get to the call frame information. */ | |
1251 | ||
1252 | struct comp_unit | |
1253 | { | |
1254 | /* Keep the bfd convenient. */ | |
1255 | bfd *abfd; | |
1256 | ||
1257 | struct objfile *objfile; | |
1258 | ||
1259 | /* Linked list of CIEs for this object. */ | |
1260 | struct dwarf2_cie *cie; | |
1261 | ||
cfc14b3a | 1262 | /* Pointer to the .debug_frame section loaded into memory. */ |
852483bc | 1263 | gdb_byte *dwarf_frame_buffer; |
cfc14b3a MK |
1264 | |
1265 | /* Length of the loaded .debug_frame section. */ | |
1266 | unsigned long dwarf_frame_size; | |
1267 | ||
1268 | /* Pointer to the .debug_frame section. */ | |
1269 | asection *dwarf_frame_section; | |
0912c7f2 MK |
1270 | |
1271 | /* Base for DW_EH_PE_datarel encodings. */ | |
1272 | bfd_vma dbase; | |
0fd85043 CV |
1273 | |
1274 | /* Base for DW_EH_PE_textrel encodings. */ | |
1275 | bfd_vma tbase; | |
cfc14b3a MK |
1276 | }; |
1277 | ||
8f22cb90 | 1278 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1279 | |
cfc14b3a | 1280 | static unsigned int |
852483bc | 1281 | read_1_byte (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1282 | { |
852483bc | 1283 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1284 | } |
1285 | ||
1286 | static unsigned int | |
852483bc | 1287 | read_4_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1288 | { |
852483bc | 1289 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1290 | } |
1291 | ||
1292 | static ULONGEST | |
852483bc | 1293 | read_8_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1294 | { |
852483bc | 1295 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1296 | } |
1297 | ||
1298 | static ULONGEST | |
852483bc | 1299 | read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1300 | { |
1301 | ULONGEST result; | |
1302 | unsigned int num_read; | |
1303 | int shift; | |
852483bc | 1304 | gdb_byte byte; |
cfc14b3a MK |
1305 | |
1306 | result = 0; | |
1307 | shift = 0; | |
1308 | num_read = 0; | |
1309 | ||
1310 | do | |
1311 | { | |
1312 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1313 | buf++; | |
1314 | num_read++; | |
1315 | result |= ((byte & 0x7f) << shift); | |
1316 | shift += 7; | |
1317 | } | |
1318 | while (byte & 0x80); | |
1319 | ||
1320 | *bytes_read_ptr = num_read; | |
1321 | ||
1322 | return result; | |
1323 | } | |
1324 | ||
1325 | static LONGEST | |
852483bc | 1326 | read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1327 | { |
1328 | LONGEST result; | |
1329 | int shift; | |
1330 | unsigned int num_read; | |
852483bc | 1331 | gdb_byte byte; |
cfc14b3a MK |
1332 | |
1333 | result = 0; | |
1334 | shift = 0; | |
1335 | num_read = 0; | |
1336 | ||
1337 | do | |
1338 | { | |
1339 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1340 | buf++; | |
1341 | num_read++; | |
1342 | result |= ((byte & 0x7f) << shift); | |
1343 | shift += 7; | |
1344 | } | |
1345 | while (byte & 0x80); | |
1346 | ||
77e0b926 DJ |
1347 | if (shift < 8 * sizeof (result) && (byte & 0x40)) |
1348 | result |= -(((LONGEST)1) << shift); | |
cfc14b3a MK |
1349 | |
1350 | *bytes_read_ptr = num_read; | |
1351 | ||
1352 | return result; | |
1353 | } | |
1354 | ||
1355 | static ULONGEST | |
852483bc | 1356 | read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1357 | { |
1358 | LONGEST result; | |
1359 | ||
852483bc | 1360 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1361 | if (result == 0xffffffff) |
1362 | { | |
852483bc | 1363 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1364 | *bytes_read_ptr = 12; |
1365 | } | |
1366 | else | |
1367 | *bytes_read_ptr = 4; | |
1368 | ||
1369 | return result; | |
1370 | } | |
1371 | \f | |
1372 | ||
1373 | /* Pointer encoding helper functions. */ | |
1374 | ||
1375 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1376 | technical reasons, it encodes addresses in its FDE's in a different | |
1377 | way. Several "pointer encodings" are supported. The encoding | |
1378 | that's used for a particular FDE is determined by the 'R' | |
1379 | augmentation in the associated CIE. The argument of this | |
1380 | augmentation is a single byte. | |
1381 | ||
1382 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1383 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1384 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1385 | address should be interpreted (absolute, relative to the current | |
1386 | position in the FDE, ...). Bit 7, indicates that the address | |
1387 | should be dereferenced. */ | |
1388 | ||
852483bc | 1389 | static gdb_byte |
cfc14b3a MK |
1390 | encoding_for_size (unsigned int size) |
1391 | { | |
1392 | switch (size) | |
1393 | { | |
1394 | case 2: | |
1395 | return DW_EH_PE_udata2; | |
1396 | case 4: | |
1397 | return DW_EH_PE_udata4; | |
1398 | case 8: | |
1399 | return DW_EH_PE_udata8; | |
1400 | default: | |
e2e0b3e5 | 1401 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1402 | } |
1403 | } | |
1404 | ||
1405 | static unsigned int | |
852483bc | 1406 | size_of_encoded_value (gdb_byte encoding) |
cfc14b3a MK |
1407 | { |
1408 | if (encoding == DW_EH_PE_omit) | |
1409 | return 0; | |
1410 | ||
1411 | switch (encoding & 0x07) | |
1412 | { | |
1413 | case DW_EH_PE_absptr: | |
1414 | return TYPE_LENGTH (builtin_type_void_data_ptr); | |
1415 | case DW_EH_PE_udata2: | |
1416 | return 2; | |
1417 | case DW_EH_PE_udata4: | |
1418 | return 4; | |
1419 | case DW_EH_PE_udata8: | |
1420 | return 8; | |
1421 | default: | |
e2e0b3e5 | 1422 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1423 | } |
1424 | } | |
1425 | ||
1426 | static CORE_ADDR | |
852483bc MK |
1427 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
1428 | gdb_byte *buf, unsigned int *bytes_read_ptr) | |
cfc14b3a | 1429 | { |
68f6cf99 MK |
1430 | int ptr_len = size_of_encoded_value (DW_EH_PE_absptr); |
1431 | ptrdiff_t offset; | |
cfc14b3a MK |
1432 | CORE_ADDR base; |
1433 | ||
1434 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1435 | FDE's. */ | |
1436 | if (encoding & DW_EH_PE_indirect) | |
1437 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1438 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1439 | |
68f6cf99 MK |
1440 | *bytes_read_ptr = 0; |
1441 | ||
cfc14b3a MK |
1442 | switch (encoding & 0x70) |
1443 | { | |
1444 | case DW_EH_PE_absptr: | |
1445 | base = 0; | |
1446 | break; | |
1447 | case DW_EH_PE_pcrel: | |
f2fec864 | 1448 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1449 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1450 | break; |
0912c7f2 MK |
1451 | case DW_EH_PE_datarel: |
1452 | base = unit->dbase; | |
1453 | break; | |
0fd85043 CV |
1454 | case DW_EH_PE_textrel: |
1455 | base = unit->tbase; | |
1456 | break; | |
03ac2a74 MK |
1457 | case DW_EH_PE_funcrel: |
1458 | /* FIXME: kettenis/20040501: For now just pretend | |
1459 | DW_EH_PE_funcrel is equivalent to DW_EH_PE_absptr. For | |
1460 | reading the initial location of an FDE it should be treated | |
1461 | as such, and currently that's the only place where this code | |
1462 | is used. */ | |
1463 | base = 0; | |
1464 | break; | |
68f6cf99 MK |
1465 | case DW_EH_PE_aligned: |
1466 | base = 0; | |
852483bc | 1467 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1468 | if ((offset % ptr_len) != 0) |
1469 | { | |
1470 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1471 | buf += *bytes_read_ptr; | |
1472 | } | |
1473 | break; | |
cfc14b3a | 1474 | default: |
e2e0b3e5 | 1475 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1476 | } |
1477 | ||
b04de778 | 1478 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1479 | { |
1480 | encoding |= encoding_for_size (ptr_len); | |
1481 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1482 | encoding |= DW_EH_PE_signed; | |
1483 | } | |
cfc14b3a MK |
1484 | |
1485 | switch (encoding & 0x0f) | |
1486 | { | |
a81b10ae MK |
1487 | case DW_EH_PE_uleb128: |
1488 | { | |
1489 | ULONGEST value; | |
852483bc | 1490 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1491 | *bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1492 | return base + value; |
1493 | } | |
cfc14b3a | 1494 | case DW_EH_PE_udata2: |
68f6cf99 | 1495 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1496 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1497 | case DW_EH_PE_udata4: | |
68f6cf99 | 1498 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1499 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1500 | case DW_EH_PE_udata8: | |
68f6cf99 | 1501 | *bytes_read_ptr += 8; |
cfc14b3a | 1502 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1503 | case DW_EH_PE_sleb128: |
1504 | { | |
1505 | LONGEST value; | |
852483bc | 1506 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1507 | *bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1508 | return base + value; |
1509 | } | |
cfc14b3a | 1510 | case DW_EH_PE_sdata2: |
68f6cf99 | 1511 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1512 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1513 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1514 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1515 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1516 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1517 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1518 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1519 | default: | |
e2e0b3e5 | 1520 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1521 | } |
1522 | } | |
1523 | \f | |
1524 | ||
1525 | /* GCC uses a single CIE for all FDEs in a .debug_frame section. | |
1526 | That's why we use a simple linked list here. */ | |
1527 | ||
1528 | static struct dwarf2_cie * | |
1529 | find_cie (struct comp_unit *unit, ULONGEST cie_pointer) | |
1530 | { | |
1531 | struct dwarf2_cie *cie = unit->cie; | |
1532 | ||
1533 | while (cie) | |
1534 | { | |
1535 | if (cie->cie_pointer == cie_pointer) | |
1536 | return cie; | |
1537 | ||
1538 | cie = cie->next; | |
1539 | } | |
1540 | ||
1541 | return NULL; | |
1542 | } | |
1543 | ||
1544 | static void | |
1545 | add_cie (struct comp_unit *unit, struct dwarf2_cie *cie) | |
1546 | { | |
1547 | cie->next = unit->cie; | |
1548 | unit->cie = cie; | |
1549 | } | |
1550 | ||
1551 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1552 | inital location associated with it into *PC. */ | |
1553 | ||
1554 | static struct dwarf2_fde * | |
1555 | dwarf2_frame_find_fde (CORE_ADDR *pc) | |
1556 | { | |
1557 | struct objfile *objfile; | |
1558 | ||
1559 | ALL_OBJFILES (objfile) | |
1560 | { | |
1561 | struct dwarf2_fde *fde; | |
1562 | CORE_ADDR offset; | |
1563 | ||
8f22cb90 | 1564 | fde = objfile_data (objfile, dwarf2_frame_objfile_data); |
4ae9ee8e DJ |
1565 | if (fde == NULL) |
1566 | continue; | |
1567 | ||
1568 | gdb_assert (objfile->section_offsets); | |
1569 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1570 | ||
cfc14b3a MK |
1571 | while (fde) |
1572 | { | |
1573 | if (*pc >= fde->initial_location + offset | |
1574 | && *pc < fde->initial_location + offset + fde->address_range) | |
1575 | { | |
1576 | *pc = fde->initial_location + offset; | |
1577 | return fde; | |
1578 | } | |
1579 | ||
1580 | fde = fde->next; | |
1581 | } | |
1582 | } | |
1583 | ||
1584 | return NULL; | |
1585 | } | |
1586 | ||
1587 | static void | |
1588 | add_fde (struct comp_unit *unit, struct dwarf2_fde *fde) | |
1589 | { | |
8f22cb90 MK |
1590 | fde->next = objfile_data (unit->objfile, dwarf2_frame_objfile_data); |
1591 | set_objfile_data (unit->objfile, dwarf2_frame_objfile_data, fde); | |
cfc14b3a MK |
1592 | } |
1593 | ||
1594 | #ifdef CC_HAS_LONG_LONG | |
1595 | #define DW64_CIE_ID 0xffffffffffffffffULL | |
1596 | #else | |
1597 | #define DW64_CIE_ID ~0 | |
1598 | #endif | |
1599 | ||
852483bc MK |
1600 | static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start, |
1601 | int eh_frame_p); | |
cfc14b3a | 1602 | |
6896c0c7 RH |
1603 | /* Decode the next CIE or FDE. Return NULL if invalid input, otherwise |
1604 | the next byte to be processed. */ | |
852483bc MK |
1605 | static gdb_byte * |
1606 | decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
cfc14b3a | 1607 | { |
852483bc | 1608 | gdb_byte *buf, *end; |
cfc14b3a MK |
1609 | LONGEST length; |
1610 | unsigned int bytes_read; | |
6896c0c7 RH |
1611 | int dwarf64_p; |
1612 | ULONGEST cie_id; | |
cfc14b3a | 1613 | ULONGEST cie_pointer; |
cfc14b3a | 1614 | |
6896c0c7 | 1615 | buf = start; |
cfc14b3a MK |
1616 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1617 | buf += bytes_read; | |
1618 | end = buf + length; | |
1619 | ||
6896c0c7 RH |
1620 | /* Are we still within the section? */ |
1621 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1622 | return NULL; | |
1623 | ||
cfc14b3a MK |
1624 | if (length == 0) |
1625 | return end; | |
1626 | ||
6896c0c7 RH |
1627 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1628 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1629 | |
6896c0c7 | 1630 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1631 | if (eh_frame_p) |
1632 | cie_id = 0; | |
1633 | else if (dwarf64_p) | |
1634 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1635 | else |
1636 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1637 | |
1638 | if (dwarf64_p) | |
1639 | { | |
1640 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1641 | buf += 8; | |
1642 | } | |
1643 | else | |
1644 | { | |
1645 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1646 | buf += 4; | |
1647 | } | |
1648 | ||
1649 | if (cie_pointer == cie_id) | |
1650 | { | |
1651 | /* This is a CIE. */ | |
1652 | struct dwarf2_cie *cie; | |
1653 | char *augmentation; | |
28ba0b33 | 1654 | unsigned int cie_version; |
cfc14b3a MK |
1655 | |
1656 | /* Record the offset into the .debug_frame section of this CIE. */ | |
1657 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1658 | ||
1659 | /* Check whether we've already read it. */ | |
1660 | if (find_cie (unit, cie_pointer)) | |
1661 | return end; | |
1662 | ||
1663 | cie = (struct dwarf2_cie *) | |
8b92e4d5 | 1664 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1665 | sizeof (struct dwarf2_cie)); |
1666 | cie->initial_instructions = NULL; | |
1667 | cie->cie_pointer = cie_pointer; | |
1668 | ||
1669 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1670 | depends on the target address size. */ |
1671 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1672 | |
56c987f6 AO |
1673 | /* We'll determine the final value later, but we need to |
1674 | initialize it conservatively. */ | |
1675 | cie->signal_frame = 0; | |
1676 | ||
cfc14b3a | 1677 | /* Check version number. */ |
28ba0b33 PB |
1678 | cie_version = read_1_byte (unit->abfd, buf); |
1679 | if (cie_version != 1 && cie_version != 3) | |
6896c0c7 | 1680 | return NULL; |
303b6f5d | 1681 | cie->version = cie_version; |
cfc14b3a MK |
1682 | buf += 1; |
1683 | ||
1684 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1685 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1686 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1687 | |
303b6f5d DJ |
1688 | /* Ignore armcc augmentations. We only use them for quirks, |
1689 | and that doesn't happen until later. */ | |
1690 | if (strncmp (augmentation, "armcc", 5) == 0) | |
1691 | augmentation += strlen (augmentation); | |
1692 | ||
cfc14b3a MK |
1693 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1694 | following the augmentation string, so it must be handled | |
1695 | first. */ | |
1696 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1697 | { | |
1698 | /* Skip. */ | |
1699 | buf += TYPE_LENGTH (builtin_type_void_data_ptr); | |
1700 | augmentation += 2; | |
1701 | } | |
1702 | ||
1703 | cie->code_alignment_factor = | |
1704 | read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1705 | buf += bytes_read; | |
1706 | ||
1707 | cie->data_alignment_factor = | |
1708 | read_signed_leb128 (unit->abfd, buf, &bytes_read); | |
1709 | buf += bytes_read; | |
1710 | ||
28ba0b33 PB |
1711 | if (cie_version == 1) |
1712 | { | |
1713 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
1714 | bytes_read = 1; | |
1715 | } | |
1716 | else | |
1717 | cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf, | |
1718 | &bytes_read); | |
4fc771b8 DJ |
1719 | cie->return_address_register |
1720 | = dwarf2_frame_adjust_regnum (current_gdbarch, | |
1721 | cie->return_address_register, | |
1722 | eh_frame_p); | |
4bf8967c | 1723 | |
28ba0b33 | 1724 | buf += bytes_read; |
cfc14b3a | 1725 | |
7131cb6e RH |
1726 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1727 | if (cie->saw_z_augmentation) | |
cfc14b3a MK |
1728 | { |
1729 | ULONGEST length; | |
1730 | ||
1731 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1732 | buf += bytes_read; | |
6896c0c7 RH |
1733 | if (buf > end) |
1734 | return NULL; | |
cfc14b3a MK |
1735 | cie->initial_instructions = buf + length; |
1736 | augmentation++; | |
1737 | } | |
1738 | ||
1739 | while (*augmentation) | |
1740 | { | |
1741 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1742 | if (*augmentation == 'L') | |
1743 | { | |
1744 | /* Skip. */ | |
1745 | buf++; | |
1746 | augmentation++; | |
1747 | } | |
1748 | ||
1749 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1750 | else if (*augmentation == 'R') | |
1751 | { | |
1752 | cie->encoding = *buf++; | |
1753 | augmentation++; | |
1754 | } | |
1755 | ||
1756 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1757 | else if (*augmentation == 'P') | |
1758 | { | |
1234d960 | 1759 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1760 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
f724bf08 MK |
1761 | read_encoded_value (unit, encoding, buf, &bytes_read); |
1762 | buf += bytes_read; | |
cfc14b3a MK |
1763 | augmentation++; |
1764 | } | |
1765 | ||
56c987f6 AO |
1766 | /* "S" indicates a signal frame, such that the return |
1767 | address must not be decremented to locate the call frame | |
1768 | info for the previous frame; it might even be the first | |
1769 | instruction of a function, so decrementing it would take | |
1770 | us to a different function. */ | |
1771 | else if (*augmentation == 'S') | |
1772 | { | |
1773 | cie->signal_frame = 1; | |
1774 | augmentation++; | |
1775 | } | |
1776 | ||
3e9a2e52 DJ |
1777 | /* Otherwise we have an unknown augmentation. Assume that either |
1778 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1779 | else |
1780 | { | |
3e9a2e52 DJ |
1781 | if (cie->initial_instructions) |
1782 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1783 | break; |
1784 | } | |
1785 | } | |
1786 | ||
1787 | cie->initial_instructions = buf; | |
1788 | cie->end = end; | |
1789 | ||
1790 | add_cie (unit, cie); | |
1791 | } | |
1792 | else | |
1793 | { | |
1794 | /* This is a FDE. */ | |
1795 | struct dwarf2_fde *fde; | |
1796 | ||
6896c0c7 RH |
1797 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1798 | address within the FDE where the CIE pointer is stored and the | |
1799 | address of the CIE. Convert it to an offset into the .eh_frame | |
1800 | section. */ | |
cfc14b3a MK |
1801 | if (eh_frame_p) |
1802 | { | |
cfc14b3a MK |
1803 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1804 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1805 | } | |
1806 | ||
6896c0c7 RH |
1807 | /* In either case, validate the result is still within the section. */ |
1808 | if (cie_pointer >= unit->dwarf_frame_size) | |
1809 | return NULL; | |
1810 | ||
cfc14b3a | 1811 | fde = (struct dwarf2_fde *) |
8b92e4d5 | 1812 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1813 | sizeof (struct dwarf2_fde)); |
1814 | fde->cie = find_cie (unit, cie_pointer); | |
1815 | if (fde->cie == NULL) | |
1816 | { | |
1817 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
1818 | eh_frame_p); | |
1819 | fde->cie = find_cie (unit, cie_pointer); | |
1820 | } | |
1821 | ||
1822 | gdb_assert (fde->cie != NULL); | |
1823 | ||
1824 | fde->initial_location = | |
1825 | read_encoded_value (unit, fde->cie->encoding, buf, &bytes_read); | |
1826 | buf += bytes_read; | |
1827 | ||
1828 | fde->address_range = | |
1829 | read_encoded_value (unit, fde->cie->encoding & 0x0f, buf, &bytes_read); | |
1830 | buf += bytes_read; | |
1831 | ||
7131cb6e RH |
1832 | /* A 'z' augmentation in the CIE implies the presence of an |
1833 | augmentation field in the FDE as well. The only thing known | |
1834 | to be in here at present is the LSDA entry for EH. So we | |
1835 | can skip the whole thing. */ | |
1836 | if (fde->cie->saw_z_augmentation) | |
1837 | { | |
1838 | ULONGEST length; | |
1839 | ||
1840 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1841 | buf += bytes_read + length; | |
6896c0c7 RH |
1842 | if (buf > end) |
1843 | return NULL; | |
7131cb6e RH |
1844 | } |
1845 | ||
cfc14b3a MK |
1846 | fde->instructions = buf; |
1847 | fde->end = end; | |
1848 | ||
4bf8967c AS |
1849 | fde->eh_frame_p = eh_frame_p; |
1850 | ||
cfc14b3a MK |
1851 | add_fde (unit, fde); |
1852 | } | |
1853 | ||
1854 | return end; | |
1855 | } | |
6896c0c7 RH |
1856 | |
1857 | /* Read a CIE or FDE in BUF and decode it. */ | |
852483bc MK |
1858 | static gdb_byte * |
1859 | decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
6896c0c7 RH |
1860 | { |
1861 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
852483bc | 1862 | gdb_byte *ret; |
6896c0c7 RH |
1863 | const char *msg; |
1864 | ptrdiff_t start_offset; | |
1865 | ||
1866 | while (1) | |
1867 | { | |
1868 | ret = decode_frame_entry_1 (unit, start, eh_frame_p); | |
1869 | if (ret != NULL) | |
1870 | break; | |
1871 | ||
1872 | /* We have corrupt input data of some form. */ | |
1873 | ||
1874 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
1875 | and mismatches wrt padding and alignment of debug sections. */ | |
1876 | /* Note that there is no requirement in the standard for any | |
1877 | alignment at all in the frame unwind sections. Testing for | |
1878 | alignment before trying to interpret data would be incorrect. | |
1879 | ||
1880 | However, GCC traditionally arranged for frame sections to be | |
1881 | sized such that the FDE length and CIE fields happen to be | |
1882 | aligned (in theory, for performance). This, unfortunately, | |
1883 | was done with .align directives, which had the side effect of | |
1884 | forcing the section to be aligned by the linker. | |
1885 | ||
1886 | This becomes a problem when you have some other producer that | |
1887 | creates frame sections that are not as strictly aligned. That | |
1888 | produces a hole in the frame info that gets filled by the | |
1889 | linker with zeros. | |
1890 | ||
1891 | The GCC behaviour is arguably a bug, but it's effectively now | |
1892 | part of the ABI, so we're now stuck with it, at least at the | |
1893 | object file level. A smart linker may decide, in the process | |
1894 | of compressing duplicate CIE information, that it can rewrite | |
1895 | the entire output section without this extra padding. */ | |
1896 | ||
1897 | start_offset = start - unit->dwarf_frame_buffer; | |
1898 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
1899 | { | |
1900 | start += 4 - (start_offset & 3); | |
1901 | workaround = ALIGN4; | |
1902 | continue; | |
1903 | } | |
1904 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
1905 | { | |
1906 | start += 8 - (start_offset & 7); | |
1907 | workaround = ALIGN8; | |
1908 | continue; | |
1909 | } | |
1910 | ||
1911 | /* Nothing left to try. Arrange to return as if we've consumed | |
1912 | the entire input section. Hopefully we'll get valid info from | |
1913 | the other of .debug_frame/.eh_frame. */ | |
1914 | workaround = FAIL; | |
1915 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
1916 | break; | |
1917 | } | |
1918 | ||
1919 | switch (workaround) | |
1920 | { | |
1921 | case NONE: | |
1922 | break; | |
1923 | ||
1924 | case ALIGN4: | |
1925 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1926 | _("Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
1927 | unit->dwarf_frame_section->owner->filename, |
1928 | unit->dwarf_frame_section->name); | |
1929 | break; | |
1930 | ||
1931 | case ALIGN8: | |
1932 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1933 | _("Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
1934 | unit->dwarf_frame_section->owner->filename, |
1935 | unit->dwarf_frame_section->name); | |
1936 | break; | |
1937 | ||
1938 | default: | |
1939 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1940 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
1941 | unit->dwarf_frame_section->owner->filename, |
1942 | unit->dwarf_frame_section->name); | |
1943 | break; | |
1944 | } | |
1945 | ||
1946 | return ret; | |
1947 | } | |
cfc14b3a MK |
1948 | \f |
1949 | ||
1950 | /* FIXME: kettenis/20030504: This still needs to be integrated with | |
1951 | dwarf2read.c in a better way. */ | |
1952 | ||
1953 | /* Imported from dwarf2read.c. */ | |
cfc14b3a | 1954 | extern asection *dwarf_frame_section; |
cfc14b3a MK |
1955 | extern asection *dwarf_eh_frame_section; |
1956 | ||
1957 | /* Imported from dwarf2read.c. */ | |
1193688d | 1958 | extern gdb_byte *dwarf2_read_section (struct objfile *objfile, asection *sectp); |
cfc14b3a MK |
1959 | |
1960 | void | |
1961 | dwarf2_build_frame_info (struct objfile *objfile) | |
1962 | { | |
1963 | struct comp_unit unit; | |
852483bc | 1964 | gdb_byte *frame_ptr; |
cfc14b3a MK |
1965 | |
1966 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
1967 | unit.abfd = objfile->obfd; | |
1968 | unit.objfile = objfile; | |
0912c7f2 | 1969 | unit.dbase = 0; |
0fd85043 | 1970 | unit.tbase = 0; |
cfc14b3a MK |
1971 | |
1972 | /* First add the information from the .eh_frame section. That way, | |
1973 | the FDEs from that section are searched last. */ | |
188dd5d6 | 1974 | if (dwarf_eh_frame_section) |
cfc14b3a | 1975 | { |
0fd85043 | 1976 | asection *got, *txt; |
0912c7f2 | 1977 | |
cfc14b3a MK |
1978 | unit.cie = NULL; |
1979 | unit.dwarf_frame_buffer = dwarf2_read_section (objfile, | |
cfc14b3a MK |
1980 | dwarf_eh_frame_section); |
1981 | ||
2c500098 | 1982 | unit.dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section); |
cfc14b3a MK |
1983 | unit.dwarf_frame_section = dwarf_eh_frame_section; |
1984 | ||
0912c7f2 | 1985 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base |
37b517aa MK |
1986 | that is used for the i386/amd64 target, which currently is |
1987 | the only target in GCC that supports/uses the | |
1988 | DW_EH_PE_datarel encoding. */ | |
0912c7f2 MK |
1989 | got = bfd_get_section_by_name (unit.abfd, ".got"); |
1990 | if (got) | |
1991 | unit.dbase = got->vma; | |
1992 | ||
22c7ba1a MK |
1993 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 |
1994 | so far. */ | |
0fd85043 CV |
1995 | txt = bfd_get_section_by_name (unit.abfd, ".text"); |
1996 | if (txt) | |
1997 | unit.tbase = txt->vma; | |
1998 | ||
cfc14b3a MK |
1999 | frame_ptr = unit.dwarf_frame_buffer; |
2000 | while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) | |
2001 | frame_ptr = decode_frame_entry (&unit, frame_ptr, 1); | |
2002 | } | |
2003 | ||
188dd5d6 | 2004 | if (dwarf_frame_section) |
cfc14b3a MK |
2005 | { |
2006 | unit.cie = NULL; | |
2007 | unit.dwarf_frame_buffer = dwarf2_read_section (objfile, | |
cfc14b3a | 2008 | dwarf_frame_section); |
2c500098 | 2009 | unit.dwarf_frame_size = bfd_get_section_size (dwarf_frame_section); |
cfc14b3a MK |
2010 | unit.dwarf_frame_section = dwarf_frame_section; |
2011 | ||
2012 | frame_ptr = unit.dwarf_frame_buffer; | |
2013 | while (frame_ptr < unit.dwarf_frame_buffer + unit.dwarf_frame_size) | |
2014 | frame_ptr = decode_frame_entry (&unit, frame_ptr, 0); | |
2015 | } | |
2016 | } | |
0d0e1a63 MK |
2017 | |
2018 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
2019 | void _initialize_dwarf2_frame (void); | |
2020 | ||
2021 | void | |
2022 | _initialize_dwarf2_frame (void) | |
2023 | { | |
030f20e1 | 2024 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2025 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 2026 | } |