Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
0fb0cc75 JB |
3 | Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009 |
4 | Free Software Foundation, Inc. | |
cfc14b3a MK |
5 | |
6 | Contributed by Mark Kettenis. | |
7 | ||
8 | This file is part of GDB. | |
9 | ||
10 | This program is free software; you can redistribute it and/or modify | |
11 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 12 | the Free Software Foundation; either version 3 of the License, or |
cfc14b3a MK |
13 | (at your option) any later version. |
14 | ||
15 | This program is distributed in the hope that it will be useful, | |
16 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | GNU General Public License for more details. | |
19 | ||
20 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
cfc14b3a MK |
22 | |
23 | #include "defs.h" | |
24 | #include "dwarf2expr.h" | |
25 | #include "elf/dwarf2.h" | |
26 | #include "frame.h" | |
27 | #include "frame-base.h" | |
28 | #include "frame-unwind.h" | |
29 | #include "gdbcore.h" | |
30 | #include "gdbtypes.h" | |
31 | #include "symtab.h" | |
32 | #include "objfiles.h" | |
33 | #include "regcache.h" | |
f2da6b3a | 34 | #include "value.h" |
cfc14b3a MK |
35 | |
36 | #include "gdb_assert.h" | |
37 | #include "gdb_string.h" | |
38 | ||
6896c0c7 | 39 | #include "complaints.h" |
cfc14b3a MK |
40 | #include "dwarf2-frame.h" |
41 | ||
ae0d2f24 UW |
42 | struct comp_unit; |
43 | ||
cfc14b3a MK |
44 | /* Call Frame Information (CFI). */ |
45 | ||
46 | /* Common Information Entry (CIE). */ | |
47 | ||
48 | struct dwarf2_cie | |
49 | { | |
ae0d2f24 UW |
50 | /* Computation Unit for this CIE. */ |
51 | struct comp_unit *unit; | |
52 | ||
cfc14b3a MK |
53 | /* Offset into the .debug_frame section where this CIE was found. |
54 | Used to identify this CIE. */ | |
55 | ULONGEST cie_pointer; | |
56 | ||
57 | /* Constant that is factored out of all advance location | |
58 | instructions. */ | |
59 | ULONGEST code_alignment_factor; | |
60 | ||
61 | /* Constants that is factored out of all offset instructions. */ | |
62 | LONGEST data_alignment_factor; | |
63 | ||
64 | /* Return address column. */ | |
65 | ULONGEST return_address_register; | |
66 | ||
67 | /* Instruction sequence to initialize a register set. */ | |
852483bc MK |
68 | gdb_byte *initial_instructions; |
69 | gdb_byte *end; | |
cfc14b3a | 70 | |
303b6f5d DJ |
71 | /* Saved augmentation, in case it's needed later. */ |
72 | char *augmentation; | |
73 | ||
cfc14b3a | 74 | /* Encoding of addresses. */ |
852483bc | 75 | gdb_byte encoding; |
cfc14b3a | 76 | |
ae0d2f24 UW |
77 | /* Target address size in bytes. */ |
78 | int addr_size; | |
79 | ||
7131cb6e RH |
80 | /* True if a 'z' augmentation existed. */ |
81 | unsigned char saw_z_augmentation; | |
82 | ||
56c987f6 AO |
83 | /* True if an 'S' augmentation existed. */ |
84 | unsigned char signal_frame; | |
85 | ||
303b6f5d DJ |
86 | /* The version recorded in the CIE. */ |
87 | unsigned char version; | |
88 | ||
cfc14b3a MK |
89 | struct dwarf2_cie *next; |
90 | }; | |
91 | ||
92 | /* Frame Description Entry (FDE). */ | |
93 | ||
94 | struct dwarf2_fde | |
95 | { | |
96 | /* CIE for this FDE. */ | |
97 | struct dwarf2_cie *cie; | |
98 | ||
99 | /* First location associated with this FDE. */ | |
100 | CORE_ADDR initial_location; | |
101 | ||
102 | /* Number of bytes of program instructions described by this FDE. */ | |
103 | CORE_ADDR address_range; | |
104 | ||
105 | /* Instruction sequence. */ | |
852483bc MK |
106 | gdb_byte *instructions; |
107 | gdb_byte *end; | |
cfc14b3a | 108 | |
4bf8967c AS |
109 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
110 | section. */ | |
111 | unsigned char eh_frame_p; | |
112 | ||
cfc14b3a MK |
113 | struct dwarf2_fde *next; |
114 | }; | |
115 | ||
ae0d2f24 UW |
116 | /* A minimal decoding of DWARF2 compilation units. We only decode |
117 | what's needed to get to the call frame information. */ | |
118 | ||
119 | struct comp_unit | |
120 | { | |
121 | /* Keep the bfd convenient. */ | |
122 | bfd *abfd; | |
123 | ||
124 | struct objfile *objfile; | |
125 | ||
126 | /* Linked list of CIEs for this object. */ | |
127 | struct dwarf2_cie *cie; | |
128 | ||
129 | /* Pointer to the .debug_frame section loaded into memory. */ | |
130 | gdb_byte *dwarf_frame_buffer; | |
131 | ||
132 | /* Length of the loaded .debug_frame section. */ | |
133 | unsigned long dwarf_frame_size; | |
134 | ||
135 | /* Pointer to the .debug_frame section. */ | |
136 | asection *dwarf_frame_section; | |
137 | ||
138 | /* Base for DW_EH_PE_datarel encodings. */ | |
139 | bfd_vma dbase; | |
140 | ||
141 | /* Base for DW_EH_PE_textrel encodings. */ | |
142 | bfd_vma tbase; | |
143 | }; | |
144 | ||
cfc14b3a | 145 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc); |
4fc771b8 DJ |
146 | |
147 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
148 | int eh_frame_p); | |
ae0d2f24 UW |
149 | |
150 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
151 | int ptr_len, gdb_byte *buf, | |
152 | unsigned int *bytes_read_ptr, | |
153 | CORE_ADDR func_base); | |
cfc14b3a MK |
154 | \f |
155 | ||
156 | /* Structure describing a frame state. */ | |
157 | ||
158 | struct dwarf2_frame_state | |
159 | { | |
160 | /* Each register save state can be described in terms of a CFA slot, | |
161 | another register, or a location expression. */ | |
162 | struct dwarf2_frame_state_reg_info | |
163 | { | |
05cbe71a | 164 | struct dwarf2_frame_state_reg *reg; |
cfc14b3a MK |
165 | int num_regs; |
166 | ||
167 | /* Used to implement DW_CFA_remember_state. */ | |
168 | struct dwarf2_frame_state_reg_info *prev; | |
169 | } regs; | |
170 | ||
171 | LONGEST cfa_offset; | |
172 | ULONGEST cfa_reg; | |
852483bc | 173 | gdb_byte *cfa_exp; |
cfc14b3a MK |
174 | enum { |
175 | CFA_UNSET, | |
176 | CFA_REG_OFFSET, | |
177 | CFA_EXP | |
178 | } cfa_how; | |
179 | ||
180 | /* The PC described by the current frame state. */ | |
181 | CORE_ADDR pc; | |
182 | ||
183 | /* Initial register set from the CIE. | |
184 | Used to implement DW_CFA_restore. */ | |
185 | struct dwarf2_frame_state_reg_info initial; | |
186 | ||
187 | /* The information we care about from the CIE. */ | |
188 | LONGEST data_align; | |
189 | ULONGEST code_align; | |
190 | ULONGEST retaddr_column; | |
303b6f5d DJ |
191 | |
192 | /* Flags for known producer quirks. */ | |
193 | ||
194 | /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa | |
195 | and DW_CFA_def_cfa_offset takes a factored offset. */ | |
196 | int armcc_cfa_offsets_sf; | |
197 | ||
198 | /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that | |
199 | the CFA is defined as REG - OFFSET rather than REG + OFFSET. */ | |
200 | int armcc_cfa_offsets_reversed; | |
cfc14b3a MK |
201 | }; |
202 | ||
203 | /* Store the length the expression for the CFA in the `cfa_reg' field, | |
204 | which is unused in that case. */ | |
205 | #define cfa_exp_len cfa_reg | |
206 | ||
f57d151a | 207 | /* Assert that the register set RS is large enough to store gdbarch_num_regs |
cfc14b3a MK |
208 | columns. If necessary, enlarge the register set. */ |
209 | ||
210 | static void | |
211 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, | |
212 | int num_regs) | |
213 | { | |
214 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
215 | ||
216 | if (num_regs <= rs->num_regs) | |
217 | return; | |
218 | ||
219 | rs->reg = (struct dwarf2_frame_state_reg *) | |
220 | xrealloc (rs->reg, num_regs * size); | |
221 | ||
222 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 223 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
224 | rs->num_regs = num_regs; |
225 | } | |
226 | ||
227 | /* Copy the register columns in register set RS into newly allocated | |
228 | memory and return a pointer to this newly created copy. */ | |
229 | ||
230 | static struct dwarf2_frame_state_reg * | |
231 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
232 | { | |
d10891d4 | 233 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
234 | struct dwarf2_frame_state_reg *reg; |
235 | ||
236 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
237 | memcpy (reg, rs->reg, size); | |
238 | ||
239 | return reg; | |
240 | } | |
241 | ||
242 | /* Release the memory allocated to register set RS. */ | |
243 | ||
244 | static void | |
245 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
246 | { | |
247 | if (rs) | |
248 | { | |
249 | dwarf2_frame_state_free_regs (rs->prev); | |
250 | ||
251 | xfree (rs->reg); | |
252 | xfree (rs); | |
253 | } | |
254 | } | |
255 | ||
256 | /* Release the memory allocated to the frame state FS. */ | |
257 | ||
258 | static void | |
259 | dwarf2_frame_state_free (void *p) | |
260 | { | |
261 | struct dwarf2_frame_state *fs = p; | |
262 | ||
263 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
264 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
265 | xfree (fs->initial.reg); | |
266 | xfree (fs->regs.reg); | |
267 | xfree (fs); | |
268 | } | |
269 | \f | |
270 | ||
271 | /* Helper functions for execute_stack_op. */ | |
272 | ||
273 | static CORE_ADDR | |
274 | read_reg (void *baton, int reg) | |
275 | { | |
4a4e5149 DJ |
276 | struct frame_info *this_frame = (struct frame_info *) baton; |
277 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
cfc14b3a | 278 | int regnum; |
852483bc | 279 | gdb_byte *buf; |
cfc14b3a | 280 | |
ad010def | 281 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); |
cfc14b3a | 282 | |
852483bc | 283 | buf = alloca (register_size (gdbarch, regnum)); |
4a4e5149 | 284 | get_frame_register (this_frame, regnum, buf); |
f2da6b3a DJ |
285 | |
286 | /* Convert the register to an integer. This returns a LONGEST | |
287 | rather than a CORE_ADDR, but unpack_pointer does the same thing | |
288 | under the covers, and this makes more sense for non-pointer | |
289 | registers. Maybe read_reg and the associated interfaces should | |
290 | deal with "struct value" instead of CORE_ADDR. */ | |
291 | return unpack_long (register_type (gdbarch, regnum), buf); | |
cfc14b3a MK |
292 | } |
293 | ||
294 | static void | |
852483bc | 295 | read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
cfc14b3a MK |
296 | { |
297 | read_memory (addr, buf, len); | |
298 | } | |
299 | ||
300 | static void | |
852483bc | 301 | no_get_frame_base (void *baton, gdb_byte **start, size_t *length) |
cfc14b3a MK |
302 | { |
303 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 304 | _("Support for DW_OP_fbreg is unimplemented")); |
cfc14b3a MK |
305 | } |
306 | ||
307 | static CORE_ADDR | |
308 | no_get_tls_address (void *baton, CORE_ADDR offset) | |
309 | { | |
310 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 311 | _("Support for DW_OP_GNU_push_tls_address is unimplemented")); |
cfc14b3a MK |
312 | } |
313 | ||
a6a5a945 LM |
314 | /* Execute the required actions for both the DW_CFA_restore and |
315 | DW_CFA_restore_extended instructions. */ | |
316 | static void | |
317 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
318 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
319 | { | |
320 | ULONGEST reg; | |
321 | ||
322 | gdb_assert (fs->initial.reg); | |
323 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); | |
324 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
325 | ||
326 | /* Check if this register was explicitly initialized in the | |
327 | CIE initial instructions. If not, default the rule to | |
328 | UNSPECIFIED. */ | |
329 | if (reg < fs->initial.num_regs) | |
330 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
331 | else | |
332 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
333 | ||
334 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
335 | complaint (&symfile_complaints, _("\ | |
336 | incomplete CFI data; DW_CFA_restore unspecified\n\ | |
337 | register %s (#%d) at 0x%s"), | |
338 | gdbarch_register_name | |
339 | (gdbarch, gdbarch_dwarf2_reg_to_regnum (gdbarch, reg)), | |
340 | gdbarch_dwarf2_reg_to_regnum (gdbarch, reg), | |
341 | paddr (fs->pc)); | |
342 | } | |
343 | ||
cfc14b3a | 344 | static CORE_ADDR |
ae0d2f24 | 345 | execute_stack_op (gdb_byte *exp, ULONGEST len, int addr_size, |
4a4e5149 | 346 | struct frame_info *this_frame, CORE_ADDR initial) |
cfc14b3a MK |
347 | { |
348 | struct dwarf_expr_context *ctx; | |
349 | CORE_ADDR result; | |
350 | ||
351 | ctx = new_dwarf_expr_context (); | |
f7fd4728 | 352 | ctx->gdbarch = get_frame_arch (this_frame); |
ae0d2f24 | 353 | ctx->addr_size = addr_size; |
4a4e5149 | 354 | ctx->baton = this_frame; |
cfc14b3a MK |
355 | ctx->read_reg = read_reg; |
356 | ctx->read_mem = read_mem; | |
357 | ctx->get_frame_base = no_get_frame_base; | |
358 | ctx->get_tls_address = no_get_tls_address; | |
359 | ||
360 | dwarf_expr_push (ctx, initial); | |
361 | dwarf_expr_eval (ctx, exp, len); | |
362 | result = dwarf_expr_fetch (ctx, 0); | |
363 | ||
364 | if (ctx->in_reg) | |
4a4e5149 | 365 | result = read_reg (this_frame, result); |
cfc14b3a MK |
366 | |
367 | free_dwarf_expr_context (ctx); | |
368 | ||
369 | return result; | |
370 | } | |
371 | \f | |
372 | ||
373 | static void | |
ae0d2f24 | 374 | execute_cfa_program (struct dwarf2_fde *fde, gdb_byte *insn_ptr, |
4a4e5149 | 375 | gdb_byte *insn_end, struct frame_info *this_frame, |
ae0d2f24 | 376 | struct dwarf2_frame_state *fs) |
cfc14b3a | 377 | { |
ae0d2f24 | 378 | int eh_frame_p = fde->eh_frame_p; |
4a4e5149 | 379 | CORE_ADDR pc = get_frame_pc (this_frame); |
cfc14b3a | 380 | int bytes_read; |
4a4e5149 | 381 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
cfc14b3a MK |
382 | |
383 | while (insn_ptr < insn_end && fs->pc <= pc) | |
384 | { | |
852483bc | 385 | gdb_byte insn = *insn_ptr++; |
cfc14b3a MK |
386 | ULONGEST utmp, reg; |
387 | LONGEST offset; | |
388 | ||
389 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
390 | fs->pc += (insn & 0x3f) * fs->code_align; | |
391 | else if ((insn & 0xc0) == DW_CFA_offset) | |
392 | { | |
393 | reg = insn & 0x3f; | |
4fc771b8 | 394 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
395 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
396 | offset = utmp * fs->data_align; | |
397 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 398 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
399 | fs->regs.reg[reg].loc.offset = offset; |
400 | } | |
401 | else if ((insn & 0xc0) == DW_CFA_restore) | |
402 | { | |
cfc14b3a | 403 | reg = insn & 0x3f; |
a6a5a945 | 404 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
405 | } |
406 | else | |
407 | { | |
408 | switch (insn) | |
409 | { | |
410 | case DW_CFA_set_loc: | |
ae0d2f24 UW |
411 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
412 | fde->cie->addr_size, insn_ptr, | |
413 | &bytes_read, fde->initial_location); | |
414 | /* Apply the objfile offset for relocatable objects. */ | |
415 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
416 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
417 | insn_ptr += bytes_read; |
418 | break; | |
419 | ||
420 | case DW_CFA_advance_loc1: | |
421 | utmp = extract_unsigned_integer (insn_ptr, 1); | |
422 | fs->pc += utmp * fs->code_align; | |
423 | insn_ptr++; | |
424 | break; | |
425 | case DW_CFA_advance_loc2: | |
426 | utmp = extract_unsigned_integer (insn_ptr, 2); | |
427 | fs->pc += utmp * fs->code_align; | |
428 | insn_ptr += 2; | |
429 | break; | |
430 | case DW_CFA_advance_loc4: | |
431 | utmp = extract_unsigned_integer (insn_ptr, 4); | |
432 | fs->pc += utmp * fs->code_align; | |
433 | insn_ptr += 4; | |
434 | break; | |
435 | ||
436 | case DW_CFA_offset_extended: | |
437 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 438 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
439 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
440 | offset = utmp * fs->data_align; | |
441 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 442 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
443 | fs->regs.reg[reg].loc.offset = offset; |
444 | break; | |
445 | ||
446 | case DW_CFA_restore_extended: | |
cfc14b3a | 447 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 448 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
449 | break; |
450 | ||
451 | case DW_CFA_undefined: | |
452 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 453 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 454 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 455 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
456 | break; |
457 | ||
458 | case DW_CFA_same_value: | |
459 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 460 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 461 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 462 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
463 | break; |
464 | ||
465 | case DW_CFA_register: | |
466 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 467 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 468 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 469 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 470 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 471 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
472 | fs->regs.reg[reg].loc.reg = utmp; |
473 | break; | |
474 | ||
475 | case DW_CFA_remember_state: | |
476 | { | |
477 | struct dwarf2_frame_state_reg_info *new_rs; | |
478 | ||
479 | new_rs = XMALLOC (struct dwarf2_frame_state_reg_info); | |
480 | *new_rs = fs->regs; | |
481 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
482 | fs->regs.prev = new_rs; | |
483 | } | |
484 | break; | |
485 | ||
486 | case DW_CFA_restore_state: | |
487 | { | |
488 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
489 | ||
50ea7769 MK |
490 | if (old_rs == NULL) |
491 | { | |
e2e0b3e5 AC |
492 | complaint (&symfile_complaints, _("\ |
493 | bad CFI data; mismatched DW_CFA_restore_state at 0x%s"), paddr (fs->pc)); | |
50ea7769 MK |
494 | } |
495 | else | |
496 | { | |
497 | xfree (fs->regs.reg); | |
498 | fs->regs = *old_rs; | |
499 | xfree (old_rs); | |
500 | } | |
cfc14b3a MK |
501 | } |
502 | break; | |
503 | ||
504 | case DW_CFA_def_cfa: | |
505 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
506 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
507 | |
508 | if (fs->armcc_cfa_offsets_sf) | |
509 | utmp *= fs->data_align; | |
510 | ||
cfc14b3a MK |
511 | fs->cfa_offset = utmp; |
512 | fs->cfa_how = CFA_REG_OFFSET; | |
513 | break; | |
514 | ||
515 | case DW_CFA_def_cfa_register: | |
516 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
517 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
518 | eh_frame_p); | |
cfc14b3a MK |
519 | fs->cfa_how = CFA_REG_OFFSET; |
520 | break; | |
521 | ||
522 | case DW_CFA_def_cfa_offset: | |
852483bc | 523 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
524 | |
525 | if (fs->armcc_cfa_offsets_sf) | |
526 | utmp *= fs->data_align; | |
527 | ||
852483bc | 528 | fs->cfa_offset = utmp; |
cfc14b3a MK |
529 | /* cfa_how deliberately not set. */ |
530 | break; | |
531 | ||
a8504492 MK |
532 | case DW_CFA_nop: |
533 | break; | |
534 | ||
cfc14b3a MK |
535 | case DW_CFA_def_cfa_expression: |
536 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_exp_len); | |
537 | fs->cfa_exp = insn_ptr; | |
538 | fs->cfa_how = CFA_EXP; | |
539 | insn_ptr += fs->cfa_exp_len; | |
540 | break; | |
541 | ||
542 | case DW_CFA_expression: | |
543 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 544 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
545 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
546 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
547 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
548 | fs->regs.reg[reg].exp_len = utmp; | |
05cbe71a | 549 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
550 | insn_ptr += utmp; |
551 | break; | |
552 | ||
a8504492 MK |
553 | case DW_CFA_offset_extended_sf: |
554 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 555 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
a8504492 | 556 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 557 | offset *= fs->data_align; |
a8504492 | 558 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 559 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
560 | fs->regs.reg[reg].loc.offset = offset; |
561 | break; | |
562 | ||
46ea248b AO |
563 | case DW_CFA_val_offset: |
564 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
565 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
566 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
567 | offset = utmp * fs->data_align; | |
568 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
569 | fs->regs.reg[reg].loc.offset = offset; | |
570 | break; | |
571 | ||
572 | case DW_CFA_val_offset_sf: | |
573 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
574 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
575 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
576 | offset *= fs->data_align; | |
577 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
578 | fs->regs.reg[reg].loc.offset = offset; | |
579 | break; | |
580 | ||
581 | case DW_CFA_val_expression: | |
582 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
583 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
584 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
585 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
586 | fs->regs.reg[reg].exp_len = utmp; | |
587 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; | |
588 | insn_ptr += utmp; | |
589 | break; | |
590 | ||
a8504492 MK |
591 | case DW_CFA_def_cfa_sf: |
592 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->cfa_reg); | |
4fc771b8 DJ |
593 | fs->cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, fs->cfa_reg, |
594 | eh_frame_p); | |
a8504492 MK |
595 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
596 | fs->cfa_offset = offset * fs->data_align; | |
597 | fs->cfa_how = CFA_REG_OFFSET; | |
598 | break; | |
599 | ||
600 | case DW_CFA_def_cfa_offset_sf: | |
601 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
602 | fs->cfa_offset = offset * fs->data_align; | |
603 | /* cfa_how deliberately not set. */ | |
cfc14b3a MK |
604 | break; |
605 | ||
a77f4086 MK |
606 | case DW_CFA_GNU_window_save: |
607 | /* This is SPARC-specific code, and contains hard-coded | |
608 | constants for the register numbering scheme used by | |
609 | GCC. Rather than having a architecture-specific | |
610 | operation that's only ever used by a single | |
611 | architecture, we provide the implementation here. | |
612 | Incidentally that's what GCC does too in its | |
613 | unwinder. */ | |
614 | { | |
4a4e5149 | 615 | int size = register_size (gdbarch, 0); |
a77f4086 MK |
616 | dwarf2_frame_state_alloc_regs (&fs->regs, 32); |
617 | for (reg = 8; reg < 16; reg++) | |
618 | { | |
619 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; | |
620 | fs->regs.reg[reg].loc.reg = reg + 16; | |
621 | } | |
622 | for (reg = 16; reg < 32; reg++) | |
623 | { | |
624 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
625 | fs->regs.reg[reg].loc.offset = (reg - 16) * size; | |
626 | } | |
627 | } | |
628 | break; | |
629 | ||
cfc14b3a MK |
630 | case DW_CFA_GNU_args_size: |
631 | /* Ignored. */ | |
632 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
633 | break; | |
634 | ||
58894217 JK |
635 | case DW_CFA_GNU_negative_offset_extended: |
636 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 637 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
58894217 JK |
638 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset); |
639 | offset *= fs->data_align; | |
640 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
641 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
642 | fs->regs.reg[reg].loc.offset = -offset; | |
643 | break; | |
644 | ||
cfc14b3a | 645 | default: |
e2e0b3e5 | 646 | internal_error (__FILE__, __LINE__, _("Unknown CFI encountered.")); |
cfc14b3a MK |
647 | } |
648 | } | |
649 | } | |
650 | ||
651 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
652 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
653 | fs->regs.prev = NULL; | |
654 | } | |
8f22cb90 | 655 | \f |
cfc14b3a | 656 | |
8f22cb90 | 657 | /* Architecture-specific operations. */ |
cfc14b3a | 658 | |
8f22cb90 MK |
659 | /* Per-architecture data key. */ |
660 | static struct gdbarch_data *dwarf2_frame_data; | |
661 | ||
662 | struct dwarf2_frame_ops | |
663 | { | |
664 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
665 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
666 | struct frame_info *); | |
3ed09a32 | 667 | |
4a4e5149 | 668 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 669 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 670 | |
4fc771b8 DJ |
671 | /* Convert .eh_frame register number to DWARF register number, or |
672 | adjust .debug_frame register number. */ | |
673 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
674 | }; |
675 | ||
8f22cb90 MK |
676 | /* Default architecture-specific register state initialization |
677 | function. */ | |
678 | ||
679 | static void | |
680 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 681 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 682 | struct frame_info *this_frame) |
8f22cb90 MK |
683 | { |
684 | /* If we have a register that acts as a program counter, mark it as | |
685 | a destination for the return address. If we have a register that | |
686 | serves as the stack pointer, arrange for it to be filled with the | |
687 | call frame address (CFA). The other registers are marked as | |
688 | unspecified. | |
689 | ||
690 | We copy the return address to the program counter, since many | |
691 | parts in GDB assume that it is possible to get the return address | |
692 | by unwinding the program counter register. However, on ISA's | |
693 | with a dedicated return address register, the CFI usually only | |
694 | contains information to unwind that return address register. | |
695 | ||
696 | The reason we're treating the stack pointer special here is | |
697 | because in many cases GCC doesn't emit CFI for the stack pointer | |
698 | and implicitly assumes that it is equal to the CFA. This makes | |
699 | some sense since the DWARF specification (version 3, draft 8, | |
700 | p. 102) says that: | |
701 | ||
702 | "Typically, the CFA is defined to be the value of the stack | |
703 | pointer at the call site in the previous frame (which may be | |
704 | different from its value on entry to the current frame)." | |
705 | ||
706 | However, this isn't true for all platforms supported by GCC | |
707 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
708 | their own architecture-specific initialization function. */ | |
05cbe71a | 709 | |
ad010def | 710 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 711 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 712 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
713 | reg->how = DWARF2_FRAME_REG_CFA; |
714 | } | |
05cbe71a | 715 | |
8f22cb90 | 716 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 717 | |
8f22cb90 | 718 | static void * |
030f20e1 | 719 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
720 | { |
721 | struct dwarf2_frame_ops *ops; | |
722 | ||
030f20e1 | 723 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
724 | ops->init_reg = dwarf2_frame_default_init_reg; |
725 | return ops; | |
726 | } | |
05cbe71a | 727 | |
8f22cb90 MK |
728 | /* Set the architecture-specific register state initialization |
729 | function for GDBARCH to INIT_REG. */ | |
730 | ||
731 | void | |
732 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
733 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
734 | struct dwarf2_frame_state_reg *, |
735 | struct frame_info *)) | |
8f22cb90 | 736 | { |
030f20e1 | 737 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 738 | |
8f22cb90 MK |
739 | ops->init_reg = init_reg; |
740 | } | |
741 | ||
742 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
743 | |
744 | static void | |
745 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 746 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 747 | struct frame_info *this_frame) |
05cbe71a | 748 | { |
030f20e1 | 749 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 750 | |
4a4e5149 | 751 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 752 | } |
3ed09a32 DJ |
753 | |
754 | /* Set the architecture-specific signal trampoline recognition | |
755 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
756 | ||
757 | void | |
758 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
759 | int (*signal_frame_p) (struct gdbarch *, | |
760 | struct frame_info *)) | |
761 | { | |
762 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
763 | ||
764 | ops->signal_frame_p = signal_frame_p; | |
765 | } | |
766 | ||
767 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 768 | THIS_FRAME. */ |
3ed09a32 DJ |
769 | |
770 | static int | |
771 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 772 | struct frame_info *this_frame) |
3ed09a32 DJ |
773 | { |
774 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
775 | ||
776 | if (ops->signal_frame_p == NULL) | |
777 | return 0; | |
4a4e5149 | 778 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 779 | } |
4bf8967c | 780 | |
4fc771b8 DJ |
781 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
782 | register numbers. */ | |
4bf8967c AS |
783 | |
784 | void | |
4fc771b8 DJ |
785 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
786 | int (*adjust_regnum) (struct gdbarch *, | |
787 | int, int)) | |
4bf8967c AS |
788 | { |
789 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
790 | ||
4fc771b8 | 791 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
792 | } |
793 | ||
4fc771b8 DJ |
794 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
795 | register. */ | |
4bf8967c | 796 | |
4fc771b8 DJ |
797 | static int |
798 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p) | |
4bf8967c AS |
799 | { |
800 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
801 | ||
4fc771b8 | 802 | if (ops->adjust_regnum == NULL) |
4bf8967c | 803 | return regnum; |
4fc771b8 | 804 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 805 | } |
303b6f5d DJ |
806 | |
807 | static void | |
808 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
809 | struct dwarf2_fde *fde) | |
810 | { | |
811 | static const char *arm_idents[] = { | |
812 | "ARM C Compiler, ADS", | |
813 | "Thumb C Compiler, ADS", | |
814 | "ARM C++ Compiler, ADS", | |
815 | "Thumb C++ Compiler, ADS", | |
816 | "ARM/Thumb C/C++ Compiler, RVCT" | |
817 | }; | |
818 | int i; | |
819 | ||
820 | struct symtab *s; | |
821 | ||
822 | s = find_pc_symtab (fs->pc); | |
823 | if (s == NULL || s->producer == NULL) | |
824 | return; | |
825 | ||
826 | for (i = 0; i < ARRAY_SIZE (arm_idents); i++) | |
827 | if (strncmp (s->producer, arm_idents[i], strlen (arm_idents[i])) == 0) | |
828 | { | |
829 | if (fde->cie->version == 1) | |
830 | fs->armcc_cfa_offsets_sf = 1; | |
831 | ||
832 | if (fde->cie->version == 1) | |
833 | fs->armcc_cfa_offsets_reversed = 1; | |
834 | ||
835 | /* The reversed offset problem is present in some compilers | |
836 | using DWARF3, but it was eventually fixed. Check the ARM | |
837 | defined augmentations, which are in the format "armcc" followed | |
838 | by a list of one-character options. The "+" option means | |
839 | this problem is fixed (no quirk needed). If the armcc | |
840 | augmentation is missing, the quirk is needed. */ | |
841 | if (fde->cie->version == 3 | |
842 | && (strncmp (fde->cie->augmentation, "armcc", 5) != 0 | |
843 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) | |
844 | fs->armcc_cfa_offsets_reversed = 1; | |
845 | ||
846 | return; | |
847 | } | |
848 | } | |
8f22cb90 MK |
849 | \f |
850 | ||
851 | struct dwarf2_frame_cache | |
852 | { | |
853 | /* DWARF Call Frame Address. */ | |
854 | CORE_ADDR cfa; | |
855 | ||
0228dfb9 DJ |
856 | /* Set if the return address column was marked as undefined. */ |
857 | int undefined_retaddr; | |
858 | ||
8f22cb90 MK |
859 | /* Saved registers, indexed by GDB register number, not by DWARF |
860 | register number. */ | |
861 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
862 | |
863 | /* Return address register. */ | |
864 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
865 | |
866 | /* Target address size in bytes. */ | |
867 | int addr_size; | |
8f22cb90 | 868 | }; |
05cbe71a | 869 | |
b9362cc7 | 870 | static struct dwarf2_frame_cache * |
4a4e5149 | 871 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
872 | { |
873 | struct cleanup *old_chain; | |
4a4e5149 | 874 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
ad010def UW |
875 | const int num_regs = gdbarch_num_regs (gdbarch) |
876 | + gdbarch_num_pseudo_regs (gdbarch); | |
cfc14b3a MK |
877 | struct dwarf2_frame_cache *cache; |
878 | struct dwarf2_frame_state *fs; | |
879 | struct dwarf2_fde *fde; | |
cfc14b3a MK |
880 | |
881 | if (*this_cache) | |
882 | return *this_cache; | |
883 | ||
884 | /* Allocate a new cache. */ | |
885 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
886 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
887 | ||
888 | /* Allocate and initialize the frame state. */ | |
889 | fs = XMALLOC (struct dwarf2_frame_state); | |
890 | memset (fs, 0, sizeof (struct dwarf2_frame_state)); | |
891 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); | |
892 | ||
893 | /* Unwind the PC. | |
894 | ||
4a4e5149 | 895 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 896 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 897 | its return address. As a result the return address will |
cfc14b3a | 898 | point at some random instruction, and the CFI for that |
e4e9607c | 899 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
900 | this problem by substracting 1 from the return address to get an |
901 | address in the middle of a presumed call instruction (or the | |
902 | instruction in the associated delay slot). This should only be | |
903 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 904 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 905 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
906 | reliable the method is though; there is the potential for the |
907 | register state pre-call being different to that on return. */ | |
4a4e5149 | 908 | fs->pc = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
909 | |
910 | /* Find the correct FDE. */ | |
911 | fde = dwarf2_frame_find_fde (&fs->pc); | |
912 | gdb_assert (fde != NULL); | |
913 | ||
914 | /* Extract any interesting information from the CIE. */ | |
915 | fs->data_align = fde->cie->data_alignment_factor; | |
916 | fs->code_align = fde->cie->code_alignment_factor; | |
917 | fs->retaddr_column = fde->cie->return_address_register; | |
ae0d2f24 | 918 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 919 | |
303b6f5d DJ |
920 | /* Check for "quirks" - known bugs in producers. */ |
921 | dwarf2_frame_find_quirks (fs, fde); | |
922 | ||
cfc14b3a | 923 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 924 | execute_cfa_program (fde, fde->cie->initial_instructions, |
4a4e5149 | 925 | fde->cie->end, this_frame, fs); |
cfc14b3a MK |
926 | |
927 | /* Save the initialized register set. */ | |
928 | fs->initial = fs->regs; | |
929 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
930 | ||
931 | /* Then decode the insns in the FDE up to our target PC. */ | |
4a4e5149 | 932 | execute_cfa_program (fde, fde->instructions, fde->end, this_frame, fs); |
cfc14b3a | 933 | |
938f5214 | 934 | /* Calculate the CFA. */ |
cfc14b3a MK |
935 | switch (fs->cfa_how) |
936 | { | |
937 | case CFA_REG_OFFSET: | |
4a4e5149 | 938 | cache->cfa = read_reg (this_frame, fs->cfa_reg); |
303b6f5d DJ |
939 | if (fs->armcc_cfa_offsets_reversed) |
940 | cache->cfa -= fs->cfa_offset; | |
941 | else | |
942 | cache->cfa += fs->cfa_offset; | |
cfc14b3a MK |
943 | break; |
944 | ||
945 | case CFA_EXP: | |
946 | cache->cfa = | |
ae0d2f24 | 947 | execute_stack_op (fs->cfa_exp, fs->cfa_exp_len, |
4a4e5149 | 948 | cache->addr_size, this_frame, 0); |
cfc14b3a MK |
949 | break; |
950 | ||
951 | default: | |
e2e0b3e5 | 952 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); |
cfc14b3a MK |
953 | } |
954 | ||
05cbe71a | 955 | /* Initialize the register state. */ |
3e2c4033 AC |
956 | { |
957 | int regnum; | |
e4e9607c | 958 | |
3e2c4033 | 959 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 960 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
961 | } |
962 | ||
963 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
964 | location information in the cache. Note that we don't skip the |
965 | return address column; it's perfectly all right for it to | |
966 | correspond to a real register. If it doesn't correspond to a | |
967 | real register, or if we shouldn't treat it as such, | |
055d23b8 | 968 | gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside |
f57d151a | 969 | the range [0, gdbarch_num_regs). */ |
3e2c4033 AC |
970 | { |
971 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 972 | |
3e2c4033 AC |
973 | for (column = 0; column < fs->regs.num_regs; column++) |
974 | { | |
3e2c4033 | 975 | /* Use the GDB register number as the destination index. */ |
ad010def | 976 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, column); |
3e2c4033 AC |
977 | |
978 | /* If there's no corresponding GDB register, ignore it. */ | |
979 | if (regnum < 0 || regnum >= num_regs) | |
980 | continue; | |
981 | ||
982 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
983 | of all debug info registers. If it doesn't, complain (but |
984 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
985 | unspecified register implies "same value" when CFI (draft |
986 | 7) specifies nothing at all. Such a register could equally | |
987 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
988 | isn't sufficient; it only checks that all registers in the |
989 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 990 | problems when a debug info register falls outside of the |
e4e9607c | 991 | table. We need a way of iterating through all the valid |
3e2c4033 | 992 | DWARF2 register numbers. */ |
05cbe71a | 993 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
994 | { |
995 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 AC |
996 | complaint (&symfile_complaints, _("\ |
997 | incomplete CFI data; unspecified registers (e.g., %s) at 0x%s"), | |
f059bf6f AC |
998 | gdbarch_register_name (gdbarch, regnum), |
999 | paddr_nz (fs->pc)); | |
1000 | } | |
35889917 MK |
1001 | else |
1002 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
1003 | } |
1004 | } | |
cfc14b3a | 1005 | |
8d5a9abc MK |
1006 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1007 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1008 | { |
1009 | int regnum; | |
1010 | ||
1011 | for (regnum = 0; regnum < num_regs; regnum++) | |
1012 | { | |
8d5a9abc MK |
1013 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1014 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1015 | { |
05cbe71a MK |
1016 | struct dwarf2_frame_state_reg *retaddr_reg = |
1017 | &fs->regs.reg[fs->retaddr_column]; | |
1018 | ||
d4f10bf2 MK |
1019 | /* It seems rather bizarre to specify an "empty" column as |
1020 | the return adress column. However, this is exactly | |
1021 | what GCC does on some targets. It turns out that GCC | |
1022 | assumes that the return address can be found in the | |
1023 | register corresponding to the return address column. | |
8d5a9abc MK |
1024 | Incidentally, that's how we should treat a return |
1025 | address column specifying "same value" too. */ | |
d4f10bf2 | 1026 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
1027 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
1028 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1029 | { |
1030 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
1031 | cache->reg[regnum] = *retaddr_reg; | |
1032 | else | |
1033 | cache->retaddr_reg = *retaddr_reg; | |
1034 | } | |
35889917 MK |
1035 | else |
1036 | { | |
8d5a9abc MK |
1037 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1038 | { | |
1039 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
1040 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
1041 | } | |
1042 | else | |
1043 | { | |
1044 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
1045 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
1046 | } | |
35889917 MK |
1047 | } |
1048 | } | |
1049 | } | |
1050 | } | |
cfc14b3a | 1051 | |
0228dfb9 DJ |
1052 | if (fs->retaddr_column < fs->regs.num_regs |
1053 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
1054 | cache->undefined_retaddr = 1; | |
1055 | ||
cfc14b3a MK |
1056 | do_cleanups (old_chain); |
1057 | ||
1058 | *this_cache = cache; | |
1059 | return cache; | |
1060 | } | |
1061 | ||
1062 | static void | |
4a4e5149 | 1063 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1064 | struct frame_id *this_id) |
1065 | { | |
1066 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1067 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1068 | |
0228dfb9 DJ |
1069 | if (cache->undefined_retaddr) |
1070 | return; | |
1071 | ||
4a4e5149 | 1072 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); |
93d42b30 DJ |
1073 | } |
1074 | ||
4a4e5149 DJ |
1075 | static struct value * |
1076 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1077 | int regnum) | |
93d42b30 | 1078 | { |
4a4e5149 | 1079 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1080 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1081 | dwarf2_frame_cache (this_frame, this_cache); |
1082 | CORE_ADDR addr; | |
1083 | int realnum; | |
cfc14b3a MK |
1084 | |
1085 | switch (cache->reg[regnum].how) | |
1086 | { | |
05cbe71a | 1087 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1088 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1089 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1090 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1091 | |
05cbe71a | 1092 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1093 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1094 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1095 | |
05cbe71a | 1096 | case DWARF2_FRAME_REG_SAVED_REG: |
4a4e5149 DJ |
1097 | realnum |
1098 | = gdbarch_dwarf2_reg_to_regnum (gdbarch, cache->reg[regnum].loc.reg); | |
1099 | return frame_unwind_got_register (this_frame, regnum, realnum); | |
cfc14b3a | 1100 | |
05cbe71a | 1101 | case DWARF2_FRAME_REG_SAVED_EXP: |
4a4e5149 DJ |
1102 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1103 | cache->reg[regnum].exp_len, | |
1104 | cache->addr_size, this_frame, cache->cfa); | |
1105 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1106 | |
46ea248b | 1107 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1108 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1109 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1110 | |
1111 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
4a4e5149 DJ |
1112 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1113 | cache->reg[regnum].exp_len, | |
1114 | cache->addr_size, this_frame, cache->cfa); | |
1115 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b | 1116 | |
05cbe71a | 1117 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1118 | /* GCC, in its infinite wisdom decided to not provide unwind |
1119 | information for registers that are "same value". Since | |
1120 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1121 | registers are actually undefined (which is different to CFI | |
1122 | "undefined"). Code above issues a complaint about this. | |
1123 | Here just fudge the books, assume GCC, and that the value is | |
1124 | more inner on the stack. */ | |
4a4e5149 | 1125 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1126 | |
05cbe71a | 1127 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1128 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1129 | |
05cbe71a | 1130 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1131 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1132 | |
ea7963f0 | 1133 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1134 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1135 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1136 | |
8d5a9abc | 1137 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 DJ |
1138 | addr = cache->reg[regnum].loc.offset; |
1139 | regnum = gdbarch_dwarf2_reg_to_regnum | |
1140 | (gdbarch, cache->retaddr_reg.loc.reg); | |
1141 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1142 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1143 | |
b39cc962 DJ |
1144 | case DWARF2_FRAME_REG_FN: |
1145 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1146 | ||
cfc14b3a | 1147 | default: |
e2e0b3e5 | 1148 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1149 | } |
1150 | } | |
1151 | ||
4a4e5149 DJ |
1152 | static int |
1153 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1154 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1155 | { |
1ce5d6dd | 1156 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1157 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1158 | end up returning something past the end of this function's body. |
1159 | If the frame we're sniffing for is a signal frame whose start | |
1160 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1161 | extend one byte before its start address or we could potentially |
1162 | select the FDE of the previous function. */ | |
1163 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
56c987f6 AO |
1164 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr); |
1165 | if (!fde) | |
4a4e5149 | 1166 | return 0; |
3ed09a32 DJ |
1167 | |
1168 | /* On some targets, signal trampolines may have unwind information. | |
1169 | We need to recognize them so that we set the frame type | |
1170 | correctly. */ | |
1171 | ||
56c987f6 | 1172 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1173 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1174 | this_frame)) | |
1175 | return self->type == SIGTRAMP_FRAME; | |
1176 | ||
1177 | return self->type != SIGTRAMP_FRAME; | |
1178 | } | |
1179 | ||
1180 | static const struct frame_unwind dwarf2_frame_unwind = | |
1181 | { | |
1182 | NORMAL_FRAME, | |
1183 | dwarf2_frame_this_id, | |
1184 | dwarf2_frame_prev_register, | |
1185 | NULL, | |
1186 | dwarf2_frame_sniffer | |
1187 | }; | |
1188 | ||
1189 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1190 | { | |
1191 | SIGTRAMP_FRAME, | |
1192 | dwarf2_frame_this_id, | |
1193 | dwarf2_frame_prev_register, | |
1194 | NULL, | |
1195 | dwarf2_frame_sniffer | |
1196 | }; | |
cfc14b3a | 1197 | |
4a4e5149 DJ |
1198 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1199 | ||
1200 | void | |
1201 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1202 | { | |
1203 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); | |
1204 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1205 | } |
1206 | \f | |
1207 | ||
1208 | /* There is no explicitly defined relationship between the CFA and the | |
1209 | location of frame's local variables and arguments/parameters. | |
1210 | Therefore, frame base methods on this page should probably only be | |
1211 | used as a last resort, just to avoid printing total garbage as a | |
1212 | response to the "info frame" command. */ | |
1213 | ||
1214 | static CORE_ADDR | |
4a4e5149 | 1215 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1216 | { |
1217 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1218 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1219 | |
1220 | return cache->cfa; | |
1221 | } | |
1222 | ||
1223 | static const struct frame_base dwarf2_frame_base = | |
1224 | { | |
1225 | &dwarf2_frame_unwind, | |
1226 | dwarf2_frame_base_address, | |
1227 | dwarf2_frame_base_address, | |
1228 | dwarf2_frame_base_address | |
1229 | }; | |
1230 | ||
1231 | const struct frame_base * | |
4a4e5149 | 1232 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1233 | { |
4a4e5149 | 1234 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
93d42b30 | 1235 | if (dwarf2_frame_find_fde (&block_addr)) |
cfc14b3a MK |
1236 | return &dwarf2_frame_base; |
1237 | ||
1238 | return NULL; | |
1239 | } | |
1240 | \f | |
8f22cb90 | 1241 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1242 | |
cfc14b3a | 1243 | static unsigned int |
852483bc | 1244 | read_1_byte (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1245 | { |
852483bc | 1246 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1247 | } |
1248 | ||
1249 | static unsigned int | |
852483bc | 1250 | read_4_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1251 | { |
852483bc | 1252 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1253 | } |
1254 | ||
1255 | static ULONGEST | |
852483bc | 1256 | read_8_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1257 | { |
852483bc | 1258 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1259 | } |
1260 | ||
1261 | static ULONGEST | |
852483bc | 1262 | read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1263 | { |
1264 | ULONGEST result; | |
1265 | unsigned int num_read; | |
1266 | int shift; | |
852483bc | 1267 | gdb_byte byte; |
cfc14b3a MK |
1268 | |
1269 | result = 0; | |
1270 | shift = 0; | |
1271 | num_read = 0; | |
1272 | ||
1273 | do | |
1274 | { | |
1275 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1276 | buf++; | |
1277 | num_read++; | |
1278 | result |= ((byte & 0x7f) << shift); | |
1279 | shift += 7; | |
1280 | } | |
1281 | while (byte & 0x80); | |
1282 | ||
1283 | *bytes_read_ptr = num_read; | |
1284 | ||
1285 | return result; | |
1286 | } | |
1287 | ||
1288 | static LONGEST | |
852483bc | 1289 | read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1290 | { |
1291 | LONGEST result; | |
1292 | int shift; | |
1293 | unsigned int num_read; | |
852483bc | 1294 | gdb_byte byte; |
cfc14b3a MK |
1295 | |
1296 | result = 0; | |
1297 | shift = 0; | |
1298 | num_read = 0; | |
1299 | ||
1300 | do | |
1301 | { | |
1302 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1303 | buf++; | |
1304 | num_read++; | |
1305 | result |= ((byte & 0x7f) << shift); | |
1306 | shift += 7; | |
1307 | } | |
1308 | while (byte & 0x80); | |
1309 | ||
77e0b926 DJ |
1310 | if (shift < 8 * sizeof (result) && (byte & 0x40)) |
1311 | result |= -(((LONGEST)1) << shift); | |
cfc14b3a MK |
1312 | |
1313 | *bytes_read_ptr = num_read; | |
1314 | ||
1315 | return result; | |
1316 | } | |
1317 | ||
1318 | static ULONGEST | |
852483bc | 1319 | read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1320 | { |
1321 | LONGEST result; | |
1322 | ||
852483bc | 1323 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1324 | if (result == 0xffffffff) |
1325 | { | |
852483bc | 1326 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1327 | *bytes_read_ptr = 12; |
1328 | } | |
1329 | else | |
1330 | *bytes_read_ptr = 4; | |
1331 | ||
1332 | return result; | |
1333 | } | |
1334 | \f | |
1335 | ||
1336 | /* Pointer encoding helper functions. */ | |
1337 | ||
1338 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1339 | technical reasons, it encodes addresses in its FDE's in a different | |
1340 | way. Several "pointer encodings" are supported. The encoding | |
1341 | that's used for a particular FDE is determined by the 'R' | |
1342 | augmentation in the associated CIE. The argument of this | |
1343 | augmentation is a single byte. | |
1344 | ||
1345 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1346 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1347 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1348 | address should be interpreted (absolute, relative to the current | |
1349 | position in the FDE, ...). Bit 7, indicates that the address | |
1350 | should be dereferenced. */ | |
1351 | ||
852483bc | 1352 | static gdb_byte |
cfc14b3a MK |
1353 | encoding_for_size (unsigned int size) |
1354 | { | |
1355 | switch (size) | |
1356 | { | |
1357 | case 2: | |
1358 | return DW_EH_PE_udata2; | |
1359 | case 4: | |
1360 | return DW_EH_PE_udata4; | |
1361 | case 8: | |
1362 | return DW_EH_PE_udata8; | |
1363 | default: | |
e2e0b3e5 | 1364 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1365 | } |
1366 | } | |
1367 | ||
cfc14b3a | 1368 | static CORE_ADDR |
852483bc | 1369 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
ae0d2f24 UW |
1370 | int ptr_len, gdb_byte *buf, unsigned int *bytes_read_ptr, |
1371 | CORE_ADDR func_base) | |
cfc14b3a | 1372 | { |
68f6cf99 | 1373 | ptrdiff_t offset; |
cfc14b3a MK |
1374 | CORE_ADDR base; |
1375 | ||
1376 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1377 | FDE's. */ | |
1378 | if (encoding & DW_EH_PE_indirect) | |
1379 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1380 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1381 | |
68f6cf99 MK |
1382 | *bytes_read_ptr = 0; |
1383 | ||
cfc14b3a MK |
1384 | switch (encoding & 0x70) |
1385 | { | |
1386 | case DW_EH_PE_absptr: | |
1387 | base = 0; | |
1388 | break; | |
1389 | case DW_EH_PE_pcrel: | |
f2fec864 | 1390 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1391 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1392 | break; |
0912c7f2 MK |
1393 | case DW_EH_PE_datarel: |
1394 | base = unit->dbase; | |
1395 | break; | |
0fd85043 CV |
1396 | case DW_EH_PE_textrel: |
1397 | base = unit->tbase; | |
1398 | break; | |
03ac2a74 | 1399 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1400 | base = func_base; |
03ac2a74 | 1401 | break; |
68f6cf99 MK |
1402 | case DW_EH_PE_aligned: |
1403 | base = 0; | |
852483bc | 1404 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1405 | if ((offset % ptr_len) != 0) |
1406 | { | |
1407 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1408 | buf += *bytes_read_ptr; | |
1409 | } | |
1410 | break; | |
cfc14b3a | 1411 | default: |
e2e0b3e5 | 1412 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1413 | } |
1414 | ||
b04de778 | 1415 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1416 | { |
1417 | encoding |= encoding_for_size (ptr_len); | |
1418 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1419 | encoding |= DW_EH_PE_signed; | |
1420 | } | |
cfc14b3a MK |
1421 | |
1422 | switch (encoding & 0x0f) | |
1423 | { | |
a81b10ae MK |
1424 | case DW_EH_PE_uleb128: |
1425 | { | |
1426 | ULONGEST value; | |
852483bc | 1427 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1428 | *bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1429 | return base + value; |
1430 | } | |
cfc14b3a | 1431 | case DW_EH_PE_udata2: |
68f6cf99 | 1432 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1433 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1434 | case DW_EH_PE_udata4: | |
68f6cf99 | 1435 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1436 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1437 | case DW_EH_PE_udata8: | |
68f6cf99 | 1438 | *bytes_read_ptr += 8; |
cfc14b3a | 1439 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1440 | case DW_EH_PE_sleb128: |
1441 | { | |
1442 | LONGEST value; | |
852483bc | 1443 | gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
a7289609 | 1444 | *bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1445 | return base + value; |
1446 | } | |
cfc14b3a | 1447 | case DW_EH_PE_sdata2: |
68f6cf99 | 1448 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1449 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1450 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1451 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1452 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1453 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1454 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1455 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1456 | default: | |
e2e0b3e5 | 1457 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1458 | } |
1459 | } | |
1460 | \f | |
1461 | ||
1462 | /* GCC uses a single CIE for all FDEs in a .debug_frame section. | |
1463 | That's why we use a simple linked list here. */ | |
1464 | ||
1465 | static struct dwarf2_cie * | |
1466 | find_cie (struct comp_unit *unit, ULONGEST cie_pointer) | |
1467 | { | |
1468 | struct dwarf2_cie *cie = unit->cie; | |
1469 | ||
1470 | while (cie) | |
1471 | { | |
1472 | if (cie->cie_pointer == cie_pointer) | |
1473 | return cie; | |
1474 | ||
1475 | cie = cie->next; | |
1476 | } | |
1477 | ||
1478 | return NULL; | |
1479 | } | |
1480 | ||
1481 | static void | |
1482 | add_cie (struct comp_unit *unit, struct dwarf2_cie *cie) | |
1483 | { | |
1484 | cie->next = unit->cie; | |
1485 | unit->cie = cie; | |
ae0d2f24 | 1486 | cie->unit = unit; |
cfc14b3a MK |
1487 | } |
1488 | ||
1489 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1490 | inital location associated with it into *PC. */ | |
1491 | ||
1492 | static struct dwarf2_fde * | |
1493 | dwarf2_frame_find_fde (CORE_ADDR *pc) | |
1494 | { | |
1495 | struct objfile *objfile; | |
1496 | ||
1497 | ALL_OBJFILES (objfile) | |
1498 | { | |
1499 | struct dwarf2_fde *fde; | |
1500 | CORE_ADDR offset; | |
1501 | ||
8f22cb90 | 1502 | fde = objfile_data (objfile, dwarf2_frame_objfile_data); |
4ae9ee8e DJ |
1503 | if (fde == NULL) |
1504 | continue; | |
1505 | ||
1506 | gdb_assert (objfile->section_offsets); | |
1507 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1508 | ||
cfc14b3a MK |
1509 | while (fde) |
1510 | { | |
1511 | if (*pc >= fde->initial_location + offset | |
1512 | && *pc < fde->initial_location + offset + fde->address_range) | |
1513 | { | |
1514 | *pc = fde->initial_location + offset; | |
1515 | return fde; | |
1516 | } | |
1517 | ||
1518 | fde = fde->next; | |
1519 | } | |
1520 | } | |
1521 | ||
1522 | return NULL; | |
1523 | } | |
1524 | ||
1525 | static void | |
1526 | add_fde (struct comp_unit *unit, struct dwarf2_fde *fde) | |
1527 | { | |
8f22cb90 MK |
1528 | fde->next = objfile_data (unit->objfile, dwarf2_frame_objfile_data); |
1529 | set_objfile_data (unit->objfile, dwarf2_frame_objfile_data, fde); | |
cfc14b3a MK |
1530 | } |
1531 | ||
1532 | #ifdef CC_HAS_LONG_LONG | |
1533 | #define DW64_CIE_ID 0xffffffffffffffffULL | |
1534 | #else | |
1535 | #define DW64_CIE_ID ~0 | |
1536 | #endif | |
1537 | ||
852483bc MK |
1538 | static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start, |
1539 | int eh_frame_p); | |
cfc14b3a | 1540 | |
6896c0c7 RH |
1541 | /* Decode the next CIE or FDE. Return NULL if invalid input, otherwise |
1542 | the next byte to be processed. */ | |
852483bc MK |
1543 | static gdb_byte * |
1544 | decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
cfc14b3a | 1545 | { |
5e2b427d | 1546 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
852483bc | 1547 | gdb_byte *buf, *end; |
cfc14b3a MK |
1548 | LONGEST length; |
1549 | unsigned int bytes_read; | |
6896c0c7 RH |
1550 | int dwarf64_p; |
1551 | ULONGEST cie_id; | |
cfc14b3a | 1552 | ULONGEST cie_pointer; |
cfc14b3a | 1553 | |
6896c0c7 | 1554 | buf = start; |
cfc14b3a MK |
1555 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1556 | buf += bytes_read; | |
1557 | end = buf + length; | |
1558 | ||
6896c0c7 RH |
1559 | /* Are we still within the section? */ |
1560 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1561 | return NULL; | |
1562 | ||
cfc14b3a MK |
1563 | if (length == 0) |
1564 | return end; | |
1565 | ||
6896c0c7 RH |
1566 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1567 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1568 | |
6896c0c7 | 1569 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1570 | if (eh_frame_p) |
1571 | cie_id = 0; | |
1572 | else if (dwarf64_p) | |
1573 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1574 | else |
1575 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1576 | |
1577 | if (dwarf64_p) | |
1578 | { | |
1579 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1580 | buf += 8; | |
1581 | } | |
1582 | else | |
1583 | { | |
1584 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1585 | buf += 4; | |
1586 | } | |
1587 | ||
1588 | if (cie_pointer == cie_id) | |
1589 | { | |
1590 | /* This is a CIE. */ | |
1591 | struct dwarf2_cie *cie; | |
1592 | char *augmentation; | |
28ba0b33 | 1593 | unsigned int cie_version; |
cfc14b3a MK |
1594 | |
1595 | /* Record the offset into the .debug_frame section of this CIE. */ | |
1596 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1597 | ||
1598 | /* Check whether we've already read it. */ | |
1599 | if (find_cie (unit, cie_pointer)) | |
1600 | return end; | |
1601 | ||
1602 | cie = (struct dwarf2_cie *) | |
8b92e4d5 | 1603 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1604 | sizeof (struct dwarf2_cie)); |
1605 | cie->initial_instructions = NULL; | |
1606 | cie->cie_pointer = cie_pointer; | |
1607 | ||
1608 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1609 | depends on the target address size. */ |
1610 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1611 | |
ae0d2f24 UW |
1612 | /* The target address size. For .eh_frame FDEs this is considered |
1613 | equal to the size of a target pointer. For .dwarf_frame FDEs, | |
1614 | this is supposed to be the target address size from the associated | |
1615 | CU header. FIXME: We do not have a good way to determine the | |
1616 | latter. Always use the target pointer size for now. */ | |
5e2b427d | 1617 | cie->addr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
ae0d2f24 | 1618 | |
56c987f6 AO |
1619 | /* We'll determine the final value later, but we need to |
1620 | initialize it conservatively. */ | |
1621 | cie->signal_frame = 0; | |
1622 | ||
cfc14b3a | 1623 | /* Check version number. */ |
28ba0b33 PB |
1624 | cie_version = read_1_byte (unit->abfd, buf); |
1625 | if (cie_version != 1 && cie_version != 3) | |
6896c0c7 | 1626 | return NULL; |
303b6f5d | 1627 | cie->version = cie_version; |
cfc14b3a MK |
1628 | buf += 1; |
1629 | ||
1630 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1631 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1632 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1633 | |
303b6f5d DJ |
1634 | /* Ignore armcc augmentations. We only use them for quirks, |
1635 | and that doesn't happen until later. */ | |
1636 | if (strncmp (augmentation, "armcc", 5) == 0) | |
1637 | augmentation += strlen (augmentation); | |
1638 | ||
cfc14b3a MK |
1639 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1640 | following the augmentation string, so it must be handled | |
1641 | first. */ | |
1642 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1643 | { | |
1644 | /* Skip. */ | |
5e2b427d | 1645 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1646 | augmentation += 2; |
1647 | } | |
1648 | ||
1649 | cie->code_alignment_factor = | |
1650 | read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1651 | buf += bytes_read; | |
1652 | ||
1653 | cie->data_alignment_factor = | |
1654 | read_signed_leb128 (unit->abfd, buf, &bytes_read); | |
1655 | buf += bytes_read; | |
1656 | ||
28ba0b33 PB |
1657 | if (cie_version == 1) |
1658 | { | |
1659 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
1660 | bytes_read = 1; | |
1661 | } | |
1662 | else | |
1663 | cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf, | |
1664 | &bytes_read); | |
4fc771b8 | 1665 | cie->return_address_register |
5e2b427d | 1666 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1667 | cie->return_address_register, |
1668 | eh_frame_p); | |
4bf8967c | 1669 | |
28ba0b33 | 1670 | buf += bytes_read; |
cfc14b3a | 1671 | |
7131cb6e RH |
1672 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1673 | if (cie->saw_z_augmentation) | |
cfc14b3a MK |
1674 | { |
1675 | ULONGEST length; | |
1676 | ||
1677 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1678 | buf += bytes_read; | |
6896c0c7 RH |
1679 | if (buf > end) |
1680 | return NULL; | |
cfc14b3a MK |
1681 | cie->initial_instructions = buf + length; |
1682 | augmentation++; | |
1683 | } | |
1684 | ||
1685 | while (*augmentation) | |
1686 | { | |
1687 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1688 | if (*augmentation == 'L') | |
1689 | { | |
1690 | /* Skip. */ | |
1691 | buf++; | |
1692 | augmentation++; | |
1693 | } | |
1694 | ||
1695 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1696 | else if (*augmentation == 'R') | |
1697 | { | |
1698 | cie->encoding = *buf++; | |
1699 | augmentation++; | |
1700 | } | |
1701 | ||
1702 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1703 | else if (*augmentation == 'P') | |
1704 | { | |
1234d960 | 1705 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1706 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
ae0d2f24 UW |
1707 | read_encoded_value (unit, encoding, cie->addr_size, |
1708 | buf, &bytes_read, 0); | |
f724bf08 | 1709 | buf += bytes_read; |
cfc14b3a MK |
1710 | augmentation++; |
1711 | } | |
1712 | ||
56c987f6 AO |
1713 | /* "S" indicates a signal frame, such that the return |
1714 | address must not be decremented to locate the call frame | |
1715 | info for the previous frame; it might even be the first | |
1716 | instruction of a function, so decrementing it would take | |
1717 | us to a different function. */ | |
1718 | else if (*augmentation == 'S') | |
1719 | { | |
1720 | cie->signal_frame = 1; | |
1721 | augmentation++; | |
1722 | } | |
1723 | ||
3e9a2e52 DJ |
1724 | /* Otherwise we have an unknown augmentation. Assume that either |
1725 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1726 | else |
1727 | { | |
3e9a2e52 DJ |
1728 | if (cie->initial_instructions) |
1729 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1730 | break; |
1731 | } | |
1732 | } | |
1733 | ||
1734 | cie->initial_instructions = buf; | |
1735 | cie->end = end; | |
1736 | ||
1737 | add_cie (unit, cie); | |
1738 | } | |
1739 | else | |
1740 | { | |
1741 | /* This is a FDE. */ | |
1742 | struct dwarf2_fde *fde; | |
1743 | ||
6896c0c7 RH |
1744 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1745 | address within the FDE where the CIE pointer is stored and the | |
1746 | address of the CIE. Convert it to an offset into the .eh_frame | |
1747 | section. */ | |
cfc14b3a MK |
1748 | if (eh_frame_p) |
1749 | { | |
cfc14b3a MK |
1750 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1751 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1752 | } | |
1753 | ||
6896c0c7 RH |
1754 | /* In either case, validate the result is still within the section. */ |
1755 | if (cie_pointer >= unit->dwarf_frame_size) | |
1756 | return NULL; | |
1757 | ||
cfc14b3a | 1758 | fde = (struct dwarf2_fde *) |
8b92e4d5 | 1759 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1760 | sizeof (struct dwarf2_fde)); |
1761 | fde->cie = find_cie (unit, cie_pointer); | |
1762 | if (fde->cie == NULL) | |
1763 | { | |
1764 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
1765 | eh_frame_p); | |
1766 | fde->cie = find_cie (unit, cie_pointer); | |
1767 | } | |
1768 | ||
1769 | gdb_assert (fde->cie != NULL); | |
1770 | ||
1771 | fde->initial_location = | |
ae0d2f24 UW |
1772 | read_encoded_value (unit, fde->cie->encoding, fde->cie->addr_size, |
1773 | buf, &bytes_read, 0); | |
cfc14b3a MK |
1774 | buf += bytes_read; |
1775 | ||
1776 | fde->address_range = | |
ae0d2f24 UW |
1777 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
1778 | fde->cie->addr_size, buf, &bytes_read, 0); | |
cfc14b3a MK |
1779 | buf += bytes_read; |
1780 | ||
7131cb6e RH |
1781 | /* A 'z' augmentation in the CIE implies the presence of an |
1782 | augmentation field in the FDE as well. The only thing known | |
1783 | to be in here at present is the LSDA entry for EH. So we | |
1784 | can skip the whole thing. */ | |
1785 | if (fde->cie->saw_z_augmentation) | |
1786 | { | |
1787 | ULONGEST length; | |
1788 | ||
1789 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1790 | buf += bytes_read + length; | |
6896c0c7 RH |
1791 | if (buf > end) |
1792 | return NULL; | |
7131cb6e RH |
1793 | } |
1794 | ||
cfc14b3a MK |
1795 | fde->instructions = buf; |
1796 | fde->end = end; | |
1797 | ||
4bf8967c AS |
1798 | fde->eh_frame_p = eh_frame_p; |
1799 | ||
cfc14b3a MK |
1800 | add_fde (unit, fde); |
1801 | } | |
1802 | ||
1803 | return end; | |
1804 | } | |
6896c0c7 RH |
1805 | |
1806 | /* Read a CIE or FDE in BUF and decode it. */ | |
852483bc MK |
1807 | static gdb_byte * |
1808 | decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p) | |
6896c0c7 RH |
1809 | { |
1810 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
852483bc | 1811 | gdb_byte *ret; |
6896c0c7 RH |
1812 | const char *msg; |
1813 | ptrdiff_t start_offset; | |
1814 | ||
1815 | while (1) | |
1816 | { | |
1817 | ret = decode_frame_entry_1 (unit, start, eh_frame_p); | |
1818 | if (ret != NULL) | |
1819 | break; | |
1820 | ||
1821 | /* We have corrupt input data of some form. */ | |
1822 | ||
1823 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
1824 | and mismatches wrt padding and alignment of debug sections. */ | |
1825 | /* Note that there is no requirement in the standard for any | |
1826 | alignment at all in the frame unwind sections. Testing for | |
1827 | alignment before trying to interpret data would be incorrect. | |
1828 | ||
1829 | However, GCC traditionally arranged for frame sections to be | |
1830 | sized such that the FDE length and CIE fields happen to be | |
1831 | aligned (in theory, for performance). This, unfortunately, | |
1832 | was done with .align directives, which had the side effect of | |
1833 | forcing the section to be aligned by the linker. | |
1834 | ||
1835 | This becomes a problem when you have some other producer that | |
1836 | creates frame sections that are not as strictly aligned. That | |
1837 | produces a hole in the frame info that gets filled by the | |
1838 | linker with zeros. | |
1839 | ||
1840 | The GCC behaviour is arguably a bug, but it's effectively now | |
1841 | part of the ABI, so we're now stuck with it, at least at the | |
1842 | object file level. A smart linker may decide, in the process | |
1843 | of compressing duplicate CIE information, that it can rewrite | |
1844 | the entire output section without this extra padding. */ | |
1845 | ||
1846 | start_offset = start - unit->dwarf_frame_buffer; | |
1847 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
1848 | { | |
1849 | start += 4 - (start_offset & 3); | |
1850 | workaround = ALIGN4; | |
1851 | continue; | |
1852 | } | |
1853 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
1854 | { | |
1855 | start += 8 - (start_offset & 7); | |
1856 | workaround = ALIGN8; | |
1857 | continue; | |
1858 | } | |
1859 | ||
1860 | /* Nothing left to try. Arrange to return as if we've consumed | |
1861 | the entire input section. Hopefully we'll get valid info from | |
1862 | the other of .debug_frame/.eh_frame. */ | |
1863 | workaround = FAIL; | |
1864 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
1865 | break; | |
1866 | } | |
1867 | ||
1868 | switch (workaround) | |
1869 | { | |
1870 | case NONE: | |
1871 | break; | |
1872 | ||
1873 | case ALIGN4: | |
1874 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1875 | _("Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
1876 | unit->dwarf_frame_section->owner->filename, |
1877 | unit->dwarf_frame_section->name); | |
1878 | break; | |
1879 | ||
1880 | case ALIGN8: | |
1881 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1882 | _("Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
1883 | unit->dwarf_frame_section->owner->filename, |
1884 | unit->dwarf_frame_section->name); | |
1885 | break; | |
1886 | ||
1887 | default: | |
1888 | complaint (&symfile_complaints, | |
e2e0b3e5 | 1889 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
1890 | unit->dwarf_frame_section->owner->filename, |
1891 | unit->dwarf_frame_section->name); | |
1892 | break; | |
1893 | } | |
1894 | ||
1895 | return ret; | |
1896 | } | |
cfc14b3a MK |
1897 | \f |
1898 | ||
1899 | /* FIXME: kettenis/20030504: This still needs to be integrated with | |
1900 | dwarf2read.c in a better way. */ | |
1901 | ||
1902 | /* Imported from dwarf2read.c. */ | |
cfc14b3a | 1903 | extern asection *dwarf_frame_section; |
cfc14b3a MK |
1904 | extern asection *dwarf_eh_frame_section; |
1905 | ||
1906 | /* Imported from dwarf2read.c. */ | |
1193688d | 1907 | extern gdb_byte *dwarf2_read_section (struct objfile *objfile, asection *sectp); |
cfc14b3a MK |
1908 | |
1909 | void | |
1910 | dwarf2_build_frame_info (struct objfile *objfile) | |
1911 | { | |
ae0d2f24 | 1912 | struct comp_unit *unit; |
852483bc | 1913 | gdb_byte *frame_ptr; |
cfc14b3a MK |
1914 | |
1915 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
ae0d2f24 UW |
1916 | unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack, |
1917 | sizeof (struct comp_unit)); | |
1918 | unit->abfd = objfile->obfd; | |
1919 | unit->objfile = objfile; | |
1920 | unit->dbase = 0; | |
1921 | unit->tbase = 0; | |
cfc14b3a MK |
1922 | |
1923 | /* First add the information from the .eh_frame section. That way, | |
1924 | the FDEs from that section are searched last. */ | |
188dd5d6 | 1925 | if (dwarf_eh_frame_section) |
cfc14b3a | 1926 | { |
0fd85043 | 1927 | asection *got, *txt; |
0912c7f2 | 1928 | |
ae0d2f24 UW |
1929 | unit->cie = NULL; |
1930 | unit->dwarf_frame_buffer = dwarf2_read_section (objfile, | |
1931 | dwarf_eh_frame_section); | |
cfc14b3a | 1932 | |
ae0d2f24 UW |
1933 | unit->dwarf_frame_size = bfd_get_section_size (dwarf_eh_frame_section); |
1934 | unit->dwarf_frame_section = dwarf_eh_frame_section; | |
cfc14b3a | 1935 | |
0912c7f2 | 1936 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base |
37b517aa MK |
1937 | that is used for the i386/amd64 target, which currently is |
1938 | the only target in GCC that supports/uses the | |
1939 | DW_EH_PE_datarel encoding. */ | |
ae0d2f24 | 1940 | got = bfd_get_section_by_name (unit->abfd, ".got"); |
0912c7f2 | 1941 | if (got) |
ae0d2f24 | 1942 | unit->dbase = got->vma; |
0912c7f2 | 1943 | |
22c7ba1a MK |
1944 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 |
1945 | so far. */ | |
ae0d2f24 | 1946 | txt = bfd_get_section_by_name (unit->abfd, ".text"); |
0fd85043 | 1947 | if (txt) |
ae0d2f24 | 1948 | unit->tbase = txt->vma; |
0fd85043 | 1949 | |
ae0d2f24 UW |
1950 | frame_ptr = unit->dwarf_frame_buffer; |
1951 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1952 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1); | |
cfc14b3a MK |
1953 | } |
1954 | ||
188dd5d6 | 1955 | if (dwarf_frame_section) |
cfc14b3a | 1956 | { |
ae0d2f24 UW |
1957 | unit->cie = NULL; |
1958 | unit->dwarf_frame_buffer = dwarf2_read_section (objfile, | |
1959 | dwarf_frame_section); | |
1960 | unit->dwarf_frame_size = bfd_get_section_size (dwarf_frame_section); | |
1961 | unit->dwarf_frame_section = dwarf_frame_section; | |
1962 | ||
1963 | frame_ptr = unit->dwarf_frame_buffer; | |
1964 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1965 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0); | |
cfc14b3a MK |
1966 | } |
1967 | } | |
0d0e1a63 MK |
1968 | |
1969 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
1970 | void _initialize_dwarf2_frame (void); | |
1971 | ||
1972 | void | |
1973 | _initialize_dwarf2_frame (void) | |
1974 | { | |
030f20e1 | 1975 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 1976 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 1977 | } |