Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
61baf725 | 3 | Copyright (C) 2003-2017 Free Software Foundation, Inc. |
cfc14b3a MK |
4 | |
5 | Contributed by Mark Kettenis. | |
6 | ||
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
cfc14b3a MK |
12 | (at your option) any later version. |
13 | ||
14 | This program is distributed in the hope that it will be useful, | |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
cfc14b3a MK |
21 | |
22 | #include "defs.h" | |
23 | #include "dwarf2expr.h" | |
fa8f86ff | 24 | #include "dwarf2.h" |
cfc14b3a MK |
25 | #include "frame.h" |
26 | #include "frame-base.h" | |
27 | #include "frame-unwind.h" | |
28 | #include "gdbcore.h" | |
29 | #include "gdbtypes.h" | |
30 | #include "symtab.h" | |
31 | #include "objfiles.h" | |
32 | #include "regcache.h" | |
f2da6b3a | 33 | #include "value.h" |
0b722aec | 34 | #include "record.h" |
cfc14b3a | 35 | |
6896c0c7 | 36 | #include "complaints.h" |
cfc14b3a | 37 | #include "dwarf2-frame.h" |
9f6f94ff TT |
38 | #include "ax.h" |
39 | #include "dwarf2loc.h" | |
111c6489 | 40 | #include "dwarf2-frame-tailcall.h" |
cfc14b3a | 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. */ | |
f664829e DE |
68 | const gdb_byte *initial_instructions; |
69 | const 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 | ||
0963b4bd | 80 | /* Target pointer size in bytes. */ |
8da614df CV |
81 | int ptr_size; |
82 | ||
7131cb6e RH |
83 | /* True if a 'z' augmentation existed. */ |
84 | unsigned char saw_z_augmentation; | |
85 | ||
56c987f6 AO |
86 | /* True if an 'S' augmentation existed. */ |
87 | unsigned char signal_frame; | |
88 | ||
303b6f5d DJ |
89 | /* The version recorded in the CIE. */ |
90 | unsigned char version; | |
2dc7f7b3 TT |
91 | |
92 | /* The segment size. */ | |
93 | unsigned char segment_size; | |
b01c8410 | 94 | }; |
303b6f5d | 95 | |
b01c8410 PP |
96 | struct dwarf2_cie_table |
97 | { | |
98 | int num_entries; | |
99 | struct dwarf2_cie **entries; | |
cfc14b3a MK |
100 | }; |
101 | ||
102 | /* Frame Description Entry (FDE). */ | |
103 | ||
104 | struct dwarf2_fde | |
105 | { | |
106 | /* CIE for this FDE. */ | |
107 | struct dwarf2_cie *cie; | |
108 | ||
109 | /* First location associated with this FDE. */ | |
110 | CORE_ADDR initial_location; | |
111 | ||
112 | /* Number of bytes of program instructions described by this FDE. */ | |
113 | CORE_ADDR address_range; | |
114 | ||
115 | /* Instruction sequence. */ | |
f664829e DE |
116 | const gdb_byte *instructions; |
117 | const gdb_byte *end; | |
cfc14b3a | 118 | |
4bf8967c AS |
119 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
120 | section. */ | |
121 | unsigned char eh_frame_p; | |
b01c8410 | 122 | }; |
4bf8967c | 123 | |
b01c8410 PP |
124 | struct dwarf2_fde_table |
125 | { | |
126 | int num_entries; | |
127 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
128 | }; |
129 | ||
ae0d2f24 UW |
130 | /* A minimal decoding of DWARF2 compilation units. We only decode |
131 | what's needed to get to the call frame information. */ | |
132 | ||
133 | struct comp_unit | |
134 | { | |
135 | /* Keep the bfd convenient. */ | |
136 | bfd *abfd; | |
137 | ||
138 | struct objfile *objfile; | |
139 | ||
ae0d2f24 | 140 | /* Pointer to the .debug_frame section loaded into memory. */ |
d521ce57 | 141 | const gdb_byte *dwarf_frame_buffer; |
ae0d2f24 UW |
142 | |
143 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 144 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
145 | |
146 | /* Pointer to the .debug_frame section. */ | |
147 | asection *dwarf_frame_section; | |
148 | ||
149 | /* Base for DW_EH_PE_datarel encodings. */ | |
150 | bfd_vma dbase; | |
151 | ||
152 | /* Base for DW_EH_PE_textrel encodings. */ | |
153 | bfd_vma tbase; | |
154 | }; | |
155 | ||
ac56253d TT |
156 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
157 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
158 | |
159 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
160 | int eh_frame_p); | |
ae0d2f24 UW |
161 | |
162 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 163 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
164 | unsigned int *bytes_read_ptr, |
165 | CORE_ADDR func_base); | |
cfc14b3a MK |
166 | \f |
167 | ||
cfc14b3a MK |
168 | /* Store the length the expression for the CFA in the `cfa_reg' field, |
169 | which is unused in that case. */ | |
170 | #define cfa_exp_len cfa_reg | |
171 | ||
f57d151a | 172 | /* Assert that the register set RS is large enough to store gdbarch_num_regs |
cfc14b3a MK |
173 | columns. If necessary, enlarge the register set. */ |
174 | ||
b41c5a85 | 175 | void |
cfc14b3a MK |
176 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, |
177 | int num_regs) | |
178 | { | |
179 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
180 | ||
181 | if (num_regs <= rs->num_regs) | |
182 | return; | |
183 | ||
184 | rs->reg = (struct dwarf2_frame_state_reg *) | |
185 | xrealloc (rs->reg, num_regs * size); | |
186 | ||
187 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 188 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
189 | rs->num_regs = num_regs; |
190 | } | |
191 | ||
192 | /* Copy the register columns in register set RS into newly allocated | |
193 | memory and return a pointer to this newly created copy. */ | |
194 | ||
195 | static struct dwarf2_frame_state_reg * | |
196 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
197 | { | |
d10891d4 | 198 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
199 | struct dwarf2_frame_state_reg *reg; |
200 | ||
201 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
202 | memcpy (reg, rs->reg, size); | |
203 | ||
204 | return reg; | |
205 | } | |
206 | ||
207 | /* Release the memory allocated to register set RS. */ | |
208 | ||
209 | static void | |
210 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
211 | { | |
212 | if (rs) | |
213 | { | |
214 | dwarf2_frame_state_free_regs (rs->prev); | |
215 | ||
216 | xfree (rs->reg); | |
217 | xfree (rs); | |
218 | } | |
219 | } | |
220 | ||
221 | /* Release the memory allocated to the frame state FS. */ | |
222 | ||
223 | static void | |
224 | dwarf2_frame_state_free (void *p) | |
225 | { | |
9a3c8263 | 226 | struct dwarf2_frame_state *fs = (struct dwarf2_frame_state *) p; |
cfc14b3a MK |
227 | |
228 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
229 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
230 | xfree (fs->initial.reg); | |
231 | xfree (fs->regs.reg); | |
232 | xfree (fs); | |
233 | } | |
234 | \f | |
235 | ||
236 | /* Helper functions for execute_stack_op. */ | |
237 | ||
238 | static CORE_ADDR | |
192ca6d8 | 239 | read_addr_from_reg (struct frame_info *this_frame, int reg) |
cfc14b3a | 240 | { |
4a4e5149 | 241 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
0fde2c53 | 242 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); |
f2da6b3a | 243 | |
2ed3c037 | 244 | return address_from_register (regnum, this_frame); |
cfc14b3a MK |
245 | } |
246 | ||
a6a5a945 LM |
247 | /* Execute the required actions for both the DW_CFA_restore and |
248 | DW_CFA_restore_extended instructions. */ | |
249 | static void | |
250 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
251 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
252 | { | |
253 | ULONGEST reg; | |
254 | ||
255 | gdb_assert (fs->initial.reg); | |
256 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); | |
257 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
258 | ||
259 | /* Check if this register was explicitly initialized in the | |
260 | CIE initial instructions. If not, default the rule to | |
261 | UNSPECIFIED. */ | |
262 | if (reg < fs->initial.num_regs) | |
263 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
264 | else | |
265 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
266 | ||
267 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
0fde2c53 DE |
268 | { |
269 | int regnum = dwarf_reg_to_regnum (gdbarch, reg); | |
270 | ||
271 | complaint (&symfile_complaints, _("\ | |
a6a5a945 | 272 | incomplete CFI data; DW_CFA_restore unspecified\n\ |
5af949e3 | 273 | register %s (#%d) at %s"), |
0fde2c53 DE |
274 | gdbarch_register_name (gdbarch, regnum), regnum, |
275 | paddress (gdbarch, fs->pc)); | |
276 | } | |
a6a5a945 LM |
277 | } |
278 | ||
192ca6d8 | 279 | class dwarf_expr_executor : public dwarf_expr_context |
9e8b7a03 | 280 | { |
192ca6d8 TT |
281 | public: |
282 | ||
283 | struct frame_info *this_frame; | |
284 | ||
285 | CORE_ADDR read_addr_from_reg (int reg) OVERRIDE | |
286 | { | |
287 | return ::read_addr_from_reg (this_frame, reg); | |
288 | } | |
289 | ||
290 | struct value *get_reg_value (struct type *type, int reg) OVERRIDE | |
291 | { | |
292 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
293 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); | |
294 | ||
295 | return value_from_register (type, regnum, this_frame); | |
296 | } | |
297 | ||
298 | void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) OVERRIDE | |
299 | { | |
300 | read_memory (addr, buf, len); | |
301 | } | |
befbff86 TT |
302 | |
303 | void get_frame_base (const gdb_byte **start, size_t *length) OVERRIDE | |
304 | { | |
305 | invalid ("DW_OP_fbreg"); | |
306 | } | |
307 | ||
308 | void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, | |
309 | union call_site_parameter_u kind_u, | |
310 | int deref_size) OVERRIDE | |
311 | { | |
216f72a1 | 312 | invalid ("DW_OP_entry_value"); |
befbff86 TT |
313 | } |
314 | ||
315 | CORE_ADDR get_object_address () OVERRIDE | |
316 | { | |
317 | invalid ("DW_OP_push_object_address"); | |
318 | } | |
319 | ||
320 | CORE_ADDR get_frame_cfa () OVERRIDE | |
321 | { | |
322 | invalid ("DW_OP_call_frame_cfa"); | |
323 | } | |
324 | ||
325 | CORE_ADDR get_tls_address (CORE_ADDR offset) OVERRIDE | |
326 | { | |
327 | invalid ("DW_OP_form_tls_address"); | |
328 | } | |
329 | ||
330 | void dwarf_call (cu_offset die_offset) OVERRIDE | |
331 | { | |
332 | invalid ("DW_OP_call*"); | |
333 | } | |
334 | ||
335 | CORE_ADDR get_addr_index (unsigned int index) | |
336 | { | |
337 | invalid ("DW_OP_GNU_addr_index"); | |
338 | } | |
339 | ||
340 | private: | |
341 | ||
342 | void invalid (const char *op) ATTRIBUTE_NORETURN | |
343 | { | |
344 | error (_("%s is invalid in this context"), op); | |
345 | } | |
9e8b7a03 JK |
346 | }; |
347 | ||
cfc14b3a | 348 | static CORE_ADDR |
0d45f56e | 349 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
350 | CORE_ADDR offset, struct frame_info *this_frame, |
351 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a | 352 | { |
cfc14b3a MK |
353 | CORE_ADDR result; |
354 | ||
192ca6d8 | 355 | dwarf_expr_executor ctx; |
eb115069 | 356 | scoped_value_mark free_values; |
4a227398 | 357 | |
192ca6d8 | 358 | ctx.this_frame = this_frame; |
718b9626 TT |
359 | ctx.gdbarch = get_frame_arch (this_frame); |
360 | ctx.addr_size = addr_size; | |
361 | ctx.ref_addr_size = -1; | |
362 | ctx.offset = offset; | |
cfc14b3a | 363 | |
595d2e30 TT |
364 | ctx.push_address (initial, initial_in_stack_memory); |
365 | ctx.eval (exp, len); | |
cfc14b3a | 366 | |
718b9626 | 367 | if (ctx.location == DWARF_VALUE_MEMORY) |
595d2e30 | 368 | result = ctx.fetch_address (0); |
718b9626 | 369 | else if (ctx.location == DWARF_VALUE_REGISTER) |
192ca6d8 | 370 | result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0))); |
f2c7657e | 371 | else |
cec03d70 TT |
372 | { |
373 | /* This is actually invalid DWARF, but if we ever do run across | |
374 | it somehow, we might as well support it. So, instead, report | |
375 | it as unimplemented. */ | |
3e43a32a MS |
376 | error (_("\ |
377 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 378 | } |
cfc14b3a | 379 | |
cfc14b3a MK |
380 | return result; |
381 | } | |
382 | \f | |
383 | ||
111c6489 JK |
384 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
385 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
386 | execution has stopped, one can resume it on the next call. */ | |
387 | ||
388 | static const gdb_byte * | |
0d45f56e | 389 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff TT |
390 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
391 | CORE_ADDR pc, struct dwarf2_frame_state *fs) | |
cfc14b3a | 392 | { |
ae0d2f24 | 393 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 394 | unsigned int bytes_read; |
e17a4113 | 395 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
396 | |
397 | while (insn_ptr < insn_end && fs->pc <= pc) | |
398 | { | |
852483bc | 399 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
400 | uint64_t utmp, reg; |
401 | int64_t offset; | |
cfc14b3a MK |
402 | |
403 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
404 | fs->pc += (insn & 0x3f) * fs->code_align; | |
405 | else if ((insn & 0xc0) == DW_CFA_offset) | |
406 | { | |
407 | reg = insn & 0x3f; | |
4fc771b8 | 408 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 409 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
410 | offset = utmp * fs->data_align; |
411 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 412 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
413 | fs->regs.reg[reg].loc.offset = offset; |
414 | } | |
415 | else if ((insn & 0xc0) == DW_CFA_restore) | |
416 | { | |
cfc14b3a | 417 | reg = insn & 0x3f; |
a6a5a945 | 418 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
419 | } |
420 | else | |
421 | { | |
422 | switch (insn) | |
423 | { | |
424 | case DW_CFA_set_loc: | |
ae0d2f24 | 425 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 426 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
427 | &bytes_read, fde->initial_location); |
428 | /* Apply the objfile offset for relocatable objects. */ | |
429 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
430 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
431 | insn_ptr += bytes_read; |
432 | break; | |
433 | ||
434 | case DW_CFA_advance_loc1: | |
e17a4113 | 435 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
436 | fs->pc += utmp * fs->code_align; |
437 | insn_ptr++; | |
438 | break; | |
439 | case DW_CFA_advance_loc2: | |
e17a4113 | 440 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
441 | fs->pc += utmp * fs->code_align; |
442 | insn_ptr += 2; | |
443 | break; | |
444 | case DW_CFA_advance_loc4: | |
e17a4113 | 445 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
446 | fs->pc += utmp * fs->code_align; |
447 | insn_ptr += 4; | |
448 | break; | |
449 | ||
450 | case DW_CFA_offset_extended: | |
f664829e | 451 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 452 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 453 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
454 | offset = utmp * fs->data_align; |
455 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 456 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
457 | fs->regs.reg[reg].loc.offset = offset; |
458 | break; | |
459 | ||
460 | case DW_CFA_restore_extended: | |
f664829e | 461 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 462 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
463 | break; |
464 | ||
465 | case DW_CFA_undefined: | |
f664829e | 466 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 467 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 468 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 469 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
470 | break; |
471 | ||
472 | case DW_CFA_same_value: | |
f664829e | 473 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 474 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 475 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 476 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
477 | break; |
478 | ||
479 | case DW_CFA_register: | |
f664829e | 480 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 481 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 482 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 483 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 484 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 485 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
486 | fs->regs.reg[reg].loc.reg = utmp; |
487 | break; | |
488 | ||
489 | case DW_CFA_remember_state: | |
490 | { | |
491 | struct dwarf2_frame_state_reg_info *new_rs; | |
492 | ||
70ba0933 | 493 | new_rs = XNEW (struct dwarf2_frame_state_reg_info); |
cfc14b3a MK |
494 | *new_rs = fs->regs; |
495 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
496 | fs->regs.prev = new_rs; | |
497 | } | |
498 | break; | |
499 | ||
500 | case DW_CFA_restore_state: | |
501 | { | |
502 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
503 | ||
50ea7769 MK |
504 | if (old_rs == NULL) |
505 | { | |
e2e0b3e5 | 506 | complaint (&symfile_complaints, _("\ |
5af949e3 UW |
507 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
508 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
509 | } |
510 | else | |
511 | { | |
512 | xfree (fs->regs.reg); | |
513 | fs->regs = *old_rs; | |
514 | xfree (old_rs); | |
515 | } | |
cfc14b3a MK |
516 | } |
517 | break; | |
518 | ||
519 | case DW_CFA_def_cfa: | |
f664829e DE |
520 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
521 | fs->regs.cfa_reg = reg; | |
522 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
523 | |
524 | if (fs->armcc_cfa_offsets_sf) | |
525 | utmp *= fs->data_align; | |
526 | ||
2fd481e1 PP |
527 | fs->regs.cfa_offset = utmp; |
528 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
529 | break; |
530 | ||
531 | case DW_CFA_def_cfa_register: | |
f664829e DE |
532 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
533 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 PP |
534 | eh_frame_p); |
535 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
536 | break; |
537 | ||
538 | case DW_CFA_def_cfa_offset: | |
f664829e | 539 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
540 | |
541 | if (fs->armcc_cfa_offsets_sf) | |
542 | utmp *= fs->data_align; | |
543 | ||
2fd481e1 | 544 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
545 | /* cfa_how deliberately not set. */ |
546 | break; | |
547 | ||
a8504492 MK |
548 | case DW_CFA_nop: |
549 | break; | |
550 | ||
cfc14b3a | 551 | case DW_CFA_def_cfa_expression: |
f664829e DE |
552 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
553 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
554 | fs->regs.cfa_exp = insn_ptr; |
555 | fs->regs.cfa_how = CFA_EXP; | |
556 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
557 | break; |
558 | ||
559 | case DW_CFA_expression: | |
f664829e | 560 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 561 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 562 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 563 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
564 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
565 | fs->regs.reg[reg].loc.exp.len = utmp; | |
05cbe71a | 566 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
567 | insn_ptr += utmp; |
568 | break; | |
569 | ||
a8504492 | 570 | case DW_CFA_offset_extended_sf: |
f664829e | 571 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 572 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 573 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 574 | offset *= fs->data_align; |
a8504492 | 575 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 576 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
577 | fs->regs.reg[reg].loc.offset = offset; |
578 | break; | |
579 | ||
46ea248b | 580 | case DW_CFA_val_offset: |
f664829e | 581 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 582 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 583 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
584 | offset = utmp * fs->data_align; |
585 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
586 | fs->regs.reg[reg].loc.offset = offset; | |
587 | break; | |
588 | ||
589 | case DW_CFA_val_offset_sf: | |
f664829e | 590 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 591 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 592 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
593 | offset *= fs->data_align; |
594 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
595 | fs->regs.reg[reg].loc.offset = offset; | |
596 | break; | |
597 | ||
598 | case DW_CFA_val_expression: | |
f664829e | 599 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 600 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 601 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
602 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
603 | fs->regs.reg[reg].loc.exp.len = utmp; | |
46ea248b AO |
604 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; |
605 | insn_ptr += utmp; | |
606 | break; | |
607 | ||
a8504492 | 608 | case DW_CFA_def_cfa_sf: |
f664829e DE |
609 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
610 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 | 611 | eh_frame_p); |
f664829e | 612 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
613 | fs->regs.cfa_offset = offset * fs->data_align; |
614 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
615 | break; |
616 | ||
617 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 618 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 619 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 620 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
621 | break; |
622 | ||
623 | case DW_CFA_GNU_args_size: | |
624 | /* Ignored. */ | |
f664829e | 625 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
626 | break; |
627 | ||
58894217 | 628 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 629 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 630 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
631 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
632 | offset = utmp * fs->data_align; | |
58894217 JK |
633 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
634 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
635 | fs->regs.reg[reg].loc.offset = -offset; | |
636 | break; | |
637 | ||
cfc14b3a | 638 | default: |
b41c5a85 JW |
639 | if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user) |
640 | { | |
641 | /* Handle vendor-specific CFI for different architectures. */ | |
642 | if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs)) | |
643 | error (_("Call Frame Instruction op %d in vendor extension " | |
644 | "space is not handled on this architecture."), | |
645 | insn); | |
646 | } | |
647 | else | |
648 | internal_error (__FILE__, __LINE__, | |
649 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
650 | } |
651 | } | |
652 | } | |
653 | ||
111c6489 JK |
654 | if (fs->initial.reg == NULL) |
655 | { | |
656 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
657 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
658 | fs->regs.prev = NULL; | |
659 | } | |
660 | ||
661 | return insn_ptr; | |
cfc14b3a | 662 | } |
8f22cb90 | 663 | \f |
cfc14b3a | 664 | |
8f22cb90 | 665 | /* Architecture-specific operations. */ |
cfc14b3a | 666 | |
8f22cb90 MK |
667 | /* Per-architecture data key. */ |
668 | static struct gdbarch_data *dwarf2_frame_data; | |
669 | ||
670 | struct dwarf2_frame_ops | |
671 | { | |
672 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
673 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
674 | struct frame_info *); | |
3ed09a32 | 675 | |
4a4e5149 | 676 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 677 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 678 | |
4fc771b8 DJ |
679 | /* Convert .eh_frame register number to DWARF register number, or |
680 | adjust .debug_frame register number. */ | |
681 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
682 | }; |
683 | ||
8f22cb90 MK |
684 | /* Default architecture-specific register state initialization |
685 | function. */ | |
686 | ||
687 | static void | |
688 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 689 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 690 | struct frame_info *this_frame) |
8f22cb90 MK |
691 | { |
692 | /* If we have a register that acts as a program counter, mark it as | |
693 | a destination for the return address. If we have a register that | |
694 | serves as the stack pointer, arrange for it to be filled with the | |
695 | call frame address (CFA). The other registers are marked as | |
696 | unspecified. | |
697 | ||
698 | We copy the return address to the program counter, since many | |
699 | parts in GDB assume that it is possible to get the return address | |
700 | by unwinding the program counter register. However, on ISA's | |
701 | with a dedicated return address register, the CFI usually only | |
702 | contains information to unwind that return address register. | |
703 | ||
704 | The reason we're treating the stack pointer special here is | |
705 | because in many cases GCC doesn't emit CFI for the stack pointer | |
706 | and implicitly assumes that it is equal to the CFA. This makes | |
707 | some sense since the DWARF specification (version 3, draft 8, | |
708 | p. 102) says that: | |
709 | ||
710 | "Typically, the CFA is defined to be the value of the stack | |
711 | pointer at the call site in the previous frame (which may be | |
712 | different from its value on entry to the current frame)." | |
713 | ||
714 | However, this isn't true for all platforms supported by GCC | |
715 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
716 | their own architecture-specific initialization function. */ | |
05cbe71a | 717 | |
ad010def | 718 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 719 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 720 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
721 | reg->how = DWARF2_FRAME_REG_CFA; |
722 | } | |
05cbe71a | 723 | |
8f22cb90 | 724 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 725 | |
8f22cb90 | 726 | static void * |
030f20e1 | 727 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
728 | { |
729 | struct dwarf2_frame_ops *ops; | |
730 | ||
030f20e1 | 731 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
732 | ops->init_reg = dwarf2_frame_default_init_reg; |
733 | return ops; | |
734 | } | |
05cbe71a | 735 | |
8f22cb90 MK |
736 | /* Set the architecture-specific register state initialization |
737 | function for GDBARCH to INIT_REG. */ | |
738 | ||
739 | void | |
740 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
741 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
742 | struct dwarf2_frame_state_reg *, |
743 | struct frame_info *)) | |
8f22cb90 | 744 | { |
9a3c8263 SM |
745 | struct dwarf2_frame_ops *ops |
746 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 747 | |
8f22cb90 MK |
748 | ops->init_reg = init_reg; |
749 | } | |
750 | ||
751 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
752 | |
753 | static void | |
754 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 755 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 756 | struct frame_info *this_frame) |
05cbe71a | 757 | { |
9a3c8263 SM |
758 | struct dwarf2_frame_ops *ops |
759 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 760 | |
4a4e5149 | 761 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 762 | } |
3ed09a32 DJ |
763 | |
764 | /* Set the architecture-specific signal trampoline recognition | |
765 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
766 | ||
767 | void | |
768 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
769 | int (*signal_frame_p) (struct gdbarch *, | |
770 | struct frame_info *)) | |
771 | { | |
9a3c8263 SM |
772 | struct dwarf2_frame_ops *ops |
773 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
774 | |
775 | ops->signal_frame_p = signal_frame_p; | |
776 | } | |
777 | ||
778 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 779 | THIS_FRAME. */ |
3ed09a32 DJ |
780 | |
781 | static int | |
782 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 783 | struct frame_info *this_frame) |
3ed09a32 | 784 | { |
9a3c8263 SM |
785 | struct dwarf2_frame_ops *ops |
786 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
787 | |
788 | if (ops->signal_frame_p == NULL) | |
789 | return 0; | |
4a4e5149 | 790 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 791 | } |
4bf8967c | 792 | |
4fc771b8 DJ |
793 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
794 | register numbers. */ | |
4bf8967c AS |
795 | |
796 | void | |
4fc771b8 DJ |
797 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
798 | int (*adjust_regnum) (struct gdbarch *, | |
799 | int, int)) | |
4bf8967c | 800 | { |
9a3c8263 SM |
801 | struct dwarf2_frame_ops *ops |
802 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 803 | |
4fc771b8 | 804 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
805 | } |
806 | ||
4fc771b8 DJ |
807 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
808 | register. */ | |
4bf8967c | 809 | |
4fc771b8 | 810 | static int |
3e43a32a MS |
811 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
812 | int regnum, int eh_frame_p) | |
4bf8967c | 813 | { |
9a3c8263 SM |
814 | struct dwarf2_frame_ops *ops |
815 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 816 | |
4fc771b8 | 817 | if (ops->adjust_regnum == NULL) |
4bf8967c | 818 | return regnum; |
4fc771b8 | 819 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 820 | } |
303b6f5d DJ |
821 | |
822 | static void | |
823 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
824 | struct dwarf2_fde *fde) | |
825 | { | |
43f3e411 | 826 | struct compunit_symtab *cust; |
303b6f5d | 827 | |
43f3e411 DE |
828 | cust = find_pc_compunit_symtab (fs->pc); |
829 | if (cust == NULL) | |
303b6f5d DJ |
830 | return; |
831 | ||
43f3e411 | 832 | if (producer_is_realview (COMPUNIT_PRODUCER (cust))) |
a6c727b2 DJ |
833 | { |
834 | if (fde->cie->version == 1) | |
835 | fs->armcc_cfa_offsets_sf = 1; | |
836 | ||
837 | if (fde->cie->version == 1) | |
838 | fs->armcc_cfa_offsets_reversed = 1; | |
839 | ||
840 | /* The reversed offset problem is present in some compilers | |
841 | using DWARF3, but it was eventually fixed. Check the ARM | |
842 | defined augmentations, which are in the format "armcc" followed | |
843 | by a list of one-character options. The "+" option means | |
844 | this problem is fixed (no quirk needed). If the armcc | |
845 | augmentation is missing, the quirk is needed. */ | |
846 | if (fde->cie->version == 3 | |
61012eef | 847 | && (!startswith (fde->cie->augmentation, "armcc") |
a6c727b2 DJ |
848 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) |
849 | fs->armcc_cfa_offsets_reversed = 1; | |
850 | ||
851 | return; | |
852 | } | |
303b6f5d | 853 | } |
8f22cb90 MK |
854 | \f |
855 | ||
a8fd5589 TT |
856 | /* See dwarf2-frame.h. */ |
857 | ||
858 | int | |
859 | dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc, | |
860 | struct dwarf2_per_cu_data *data, | |
861 | int *regnum_out, LONGEST *offset_out, | |
862 | CORE_ADDR *text_offset_out, | |
863 | const gdb_byte **cfa_start_out, | |
864 | const gdb_byte **cfa_end_out) | |
9f6f94ff | 865 | { |
9f6f94ff | 866 | struct dwarf2_fde *fde; |
22e048c9 | 867 | CORE_ADDR text_offset; |
9f6f94ff | 868 | struct dwarf2_frame_state fs; |
9f6f94ff TT |
869 | |
870 | memset (&fs, 0, sizeof (struct dwarf2_frame_state)); | |
871 | ||
872 | fs.pc = pc; | |
873 | ||
874 | /* Find the correct FDE. */ | |
875 | fde = dwarf2_frame_find_fde (&fs.pc, &text_offset); | |
876 | if (fde == NULL) | |
877 | error (_("Could not compute CFA; needed to translate this expression")); | |
878 | ||
879 | /* Extract any interesting information from the CIE. */ | |
880 | fs.data_align = fde->cie->data_alignment_factor; | |
881 | fs.code_align = fde->cie->code_alignment_factor; | |
882 | fs.retaddr_column = fde->cie->return_address_register; | |
9f6f94ff TT |
883 | |
884 | /* Check for "quirks" - known bugs in producers. */ | |
885 | dwarf2_frame_find_quirks (&fs, fde); | |
886 | ||
887 | /* First decode all the insns in the CIE. */ | |
888 | execute_cfa_program (fde, fde->cie->initial_instructions, | |
889 | fde->cie->end, gdbarch, pc, &fs); | |
890 | ||
891 | /* Save the initialized register set. */ | |
892 | fs.initial = fs.regs; | |
893 | fs.initial.reg = dwarf2_frame_state_copy_regs (&fs.regs); | |
894 | ||
895 | /* Then decode the insns in the FDE up to our target PC. */ | |
896 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs); | |
897 | ||
898 | /* Calculate the CFA. */ | |
899 | switch (fs.regs.cfa_how) | |
900 | { | |
901 | case CFA_REG_OFFSET: | |
902 | { | |
0fde2c53 | 903 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg); |
a8fd5589 TT |
904 | |
905 | *regnum_out = regnum; | |
906 | if (fs.armcc_cfa_offsets_reversed) | |
907 | *offset_out = -fs.regs.cfa_offset; | |
908 | else | |
909 | *offset_out = fs.regs.cfa_offset; | |
910 | return 1; | |
9f6f94ff | 911 | } |
9f6f94ff TT |
912 | |
913 | case CFA_EXP: | |
a8fd5589 TT |
914 | *text_offset_out = text_offset; |
915 | *cfa_start_out = fs.regs.cfa_exp; | |
916 | *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len; | |
917 | return 0; | |
9f6f94ff TT |
918 | |
919 | default: | |
920 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
921 | } | |
922 | } | |
923 | ||
924 | \f | |
8f22cb90 MK |
925 | struct dwarf2_frame_cache |
926 | { | |
927 | /* DWARF Call Frame Address. */ | |
928 | CORE_ADDR cfa; | |
929 | ||
8fbca658 PA |
930 | /* Set if the return address column was marked as unavailable |
931 | (required non-collected memory or registers to compute). */ | |
932 | int unavailable_retaddr; | |
933 | ||
0228dfb9 DJ |
934 | /* Set if the return address column was marked as undefined. */ |
935 | int undefined_retaddr; | |
936 | ||
8f22cb90 MK |
937 | /* Saved registers, indexed by GDB register number, not by DWARF |
938 | register number. */ | |
939 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
940 | |
941 | /* Return address register. */ | |
942 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
943 | |
944 | /* Target address size in bytes. */ | |
945 | int addr_size; | |
ac56253d TT |
946 | |
947 | /* The .text offset. */ | |
948 | CORE_ADDR text_offset; | |
111c6489 | 949 | |
1ec56e88 PA |
950 | /* True if we already checked whether this frame is the bottom frame |
951 | of a virtual tail call frame chain. */ | |
952 | int checked_tailcall_bottom; | |
953 | ||
111c6489 JK |
954 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME |
955 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
956 | involved. Non-bottom frames of a virtual tail call frames chain use | |
957 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
958 | them. */ | |
959 | void *tailcall_cache; | |
1ec56e88 PA |
960 | |
961 | /* The number of bytes to subtract from TAILCALL_FRAME frames frame | |
962 | base to get the SP, to simulate the return address pushed on the | |
963 | stack. */ | |
964 | LONGEST entry_cfa_sp_offset; | |
965 | int entry_cfa_sp_offset_p; | |
8f22cb90 | 966 | }; |
05cbe71a | 967 | |
78ac5f83 TT |
968 | /* A cleanup that sets a pointer to NULL. */ |
969 | ||
970 | static void | |
971 | clear_pointer_cleanup (void *arg) | |
972 | { | |
9a3c8263 | 973 | void **ptr = (void **) arg; |
78ac5f83 TT |
974 | |
975 | *ptr = NULL; | |
976 | } | |
977 | ||
b9362cc7 | 978 | static struct dwarf2_frame_cache * |
4a4e5149 | 979 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 980 | { |
78ac5f83 | 981 | struct cleanup *reset_cache_cleanup, *old_chain; |
4a4e5149 | 982 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
ad010def UW |
983 | const int num_regs = gdbarch_num_regs (gdbarch) |
984 | + gdbarch_num_pseudo_regs (gdbarch); | |
cfc14b3a MK |
985 | struct dwarf2_frame_cache *cache; |
986 | struct dwarf2_frame_state *fs; | |
987 | struct dwarf2_fde *fde; | |
111c6489 | 988 | CORE_ADDR entry_pc; |
111c6489 | 989 | const gdb_byte *instr; |
cfc14b3a MK |
990 | |
991 | if (*this_cache) | |
9a3c8263 | 992 | return (struct dwarf2_frame_cache *) *this_cache; |
cfc14b3a MK |
993 | |
994 | /* Allocate a new cache. */ | |
995 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
996 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 997 | *this_cache = cache; |
78ac5f83 | 998 | reset_cache_cleanup = make_cleanup (clear_pointer_cleanup, this_cache); |
cfc14b3a MK |
999 | |
1000 | /* Allocate and initialize the frame state. */ | |
41bf6aca | 1001 | fs = XCNEW (struct dwarf2_frame_state); |
cfc14b3a MK |
1002 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); |
1003 | ||
1004 | /* Unwind the PC. | |
1005 | ||
4a4e5149 | 1006 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 1007 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 1008 | its return address. As a result the return address will |
cfc14b3a | 1009 | point at some random instruction, and the CFI for that |
e4e9607c | 1010 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
1011 | this problem by substracting 1 from the return address to get an |
1012 | address in the middle of a presumed call instruction (or the | |
1013 | instruction in the associated delay slot). This should only be | |
1014 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 1015 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 1016 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
1017 | reliable the method is though; there is the potential for the |
1018 | register state pre-call being different to that on return. */ | |
4a4e5149 | 1019 | fs->pc = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1020 | |
1021 | /* Find the correct FDE. */ | |
ac56253d | 1022 | fde = dwarf2_frame_find_fde (&fs->pc, &cache->text_offset); |
cfc14b3a MK |
1023 | gdb_assert (fde != NULL); |
1024 | ||
1025 | /* Extract any interesting information from the CIE. */ | |
1026 | fs->data_align = fde->cie->data_alignment_factor; | |
1027 | fs->code_align = fde->cie->code_alignment_factor; | |
1028 | fs->retaddr_column = fde->cie->return_address_register; | |
ae0d2f24 | 1029 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1030 | |
303b6f5d DJ |
1031 | /* Check for "quirks" - known bugs in producers. */ |
1032 | dwarf2_frame_find_quirks (fs, fde); | |
1033 | ||
cfc14b3a | 1034 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1035 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 JB |
1036 | fde->cie->end, gdbarch, |
1037 | get_frame_address_in_block (this_frame), fs); | |
cfc14b3a MK |
1038 | |
1039 | /* Save the initialized register set. */ | |
1040 | fs->initial = fs->regs; | |
1041 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
1042 | ||
111c6489 JK |
1043 | if (get_frame_func_if_available (this_frame, &entry_pc)) |
1044 | { | |
1045 | /* Decode the insns in the FDE up to the entry PC. */ | |
1046 | instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, | |
1047 | entry_pc, fs); | |
1048 | ||
1049 | if (fs->regs.cfa_how == CFA_REG_OFFSET | |
0fde2c53 | 1050 | && (dwarf_reg_to_regnum (gdbarch, fs->regs.cfa_reg) |
111c6489 JK |
1051 | == gdbarch_sp_regnum (gdbarch))) |
1052 | { | |
1ec56e88 PA |
1053 | cache->entry_cfa_sp_offset = fs->regs.cfa_offset; |
1054 | cache->entry_cfa_sp_offset_p = 1; | |
111c6489 JK |
1055 | } |
1056 | } | |
1057 | else | |
1058 | instr = fde->instructions; | |
1059 | ||
cfc14b3a | 1060 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1061 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
0c92d8c1 | 1062 | get_frame_address_in_block (this_frame), fs); |
cfc14b3a | 1063 | |
492d29ea | 1064 | TRY |
cfc14b3a | 1065 | { |
8fbca658 PA |
1066 | /* Calculate the CFA. */ |
1067 | switch (fs->regs.cfa_how) | |
1068 | { | |
1069 | case CFA_REG_OFFSET: | |
b1370418 | 1070 | cache->cfa = read_addr_from_reg (this_frame, fs->regs.cfa_reg); |
8fbca658 PA |
1071 | if (fs->armcc_cfa_offsets_reversed) |
1072 | cache->cfa -= fs->regs.cfa_offset; | |
1073 | else | |
1074 | cache->cfa += fs->regs.cfa_offset; | |
1075 | break; | |
1076 | ||
1077 | case CFA_EXP: | |
1078 | cache->cfa = | |
1079 | execute_stack_op (fs->regs.cfa_exp, fs->regs.cfa_exp_len, | |
1080 | cache->addr_size, cache->text_offset, | |
1081 | this_frame, 0, 0); | |
1082 | break; | |
1083 | ||
1084 | default: | |
1085 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1086 | } | |
1087 | } | |
492d29ea | 1088 | CATCH (ex, RETURN_MASK_ERROR) |
8fbca658 PA |
1089 | { |
1090 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1091 | { | |
1092 | cache->unavailable_retaddr = 1; | |
5a1cf4d6 | 1093 | do_cleanups (old_chain); |
78ac5f83 | 1094 | discard_cleanups (reset_cache_cleanup); |
8fbca658 PA |
1095 | return cache; |
1096 | } | |
cfc14b3a | 1097 | |
8fbca658 | 1098 | throw_exception (ex); |
cfc14b3a | 1099 | } |
492d29ea | 1100 | END_CATCH |
cfc14b3a | 1101 | |
05cbe71a | 1102 | /* Initialize the register state. */ |
3e2c4033 AC |
1103 | { |
1104 | int regnum; | |
e4e9607c | 1105 | |
3e2c4033 | 1106 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1107 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1108 | } |
1109 | ||
1110 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1111 | location information in the cache. Note that we don't skip the |
1112 | return address column; it's perfectly all right for it to | |
0fde2c53 | 1113 | correspond to a real register. */ |
3e2c4033 AC |
1114 | { |
1115 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1116 | |
3e2c4033 AC |
1117 | for (column = 0; column < fs->regs.num_regs; column++) |
1118 | { | |
3e2c4033 | 1119 | /* Use the GDB register number as the destination index. */ |
0fde2c53 | 1120 | int regnum = dwarf_reg_to_regnum (gdbarch, column); |
3e2c4033 | 1121 | |
0fde2c53 | 1122 | /* Protect against a target returning a bad register. */ |
3e2c4033 AC |
1123 | if (regnum < 0 || regnum >= num_regs) |
1124 | continue; | |
1125 | ||
1126 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1127 | of all debug info registers. If it doesn't, complain (but |
1128 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1129 | unspecified register implies "same value" when CFI (draft |
1130 | 7) specifies nothing at all. Such a register could equally | |
1131 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1132 | isn't sufficient; it only checks that all registers in the |
1133 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1134 | problems when a debug info register falls outside of the |
e4e9607c | 1135 | table. We need a way of iterating through all the valid |
3e2c4033 | 1136 | DWARF2 register numbers. */ |
05cbe71a | 1137 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1138 | { |
1139 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 | 1140 | complaint (&symfile_complaints, _("\ |
5af949e3 | 1141 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1142 | gdbarch_register_name (gdbarch, regnum), |
5af949e3 | 1143 | paddress (gdbarch, fs->pc)); |
f059bf6f | 1144 | } |
35889917 MK |
1145 | else |
1146 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
1147 | } |
1148 | } | |
cfc14b3a | 1149 | |
8d5a9abc MK |
1150 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1151 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1152 | { |
1153 | int regnum; | |
1154 | ||
1155 | for (regnum = 0; regnum < num_regs; regnum++) | |
1156 | { | |
8d5a9abc MK |
1157 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1158 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1159 | { |
05cbe71a MK |
1160 | struct dwarf2_frame_state_reg *retaddr_reg = |
1161 | &fs->regs.reg[fs->retaddr_column]; | |
1162 | ||
d4f10bf2 MK |
1163 | /* It seems rather bizarre to specify an "empty" column as |
1164 | the return adress column. However, this is exactly | |
1165 | what GCC does on some targets. It turns out that GCC | |
1166 | assumes that the return address can be found in the | |
1167 | register corresponding to the return address column. | |
8d5a9abc MK |
1168 | Incidentally, that's how we should treat a return |
1169 | address column specifying "same value" too. */ | |
d4f10bf2 | 1170 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
1171 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
1172 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1173 | { |
1174 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
1175 | cache->reg[regnum] = *retaddr_reg; | |
1176 | else | |
1177 | cache->retaddr_reg = *retaddr_reg; | |
1178 | } | |
35889917 MK |
1179 | else |
1180 | { | |
8d5a9abc MK |
1181 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1182 | { | |
1183 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
1184 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
1185 | } | |
1186 | else | |
1187 | { | |
1188 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
1189 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
1190 | } | |
35889917 MK |
1191 | } |
1192 | } | |
1193 | } | |
1194 | } | |
cfc14b3a | 1195 | |
0228dfb9 DJ |
1196 | if (fs->retaddr_column < fs->regs.num_regs |
1197 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
1198 | cache->undefined_retaddr = 1; | |
1199 | ||
cfc14b3a | 1200 | do_cleanups (old_chain); |
78ac5f83 | 1201 | discard_cleanups (reset_cache_cleanup); |
cfc14b3a MK |
1202 | return cache; |
1203 | } | |
1204 | ||
8fbca658 PA |
1205 | static enum unwind_stop_reason |
1206 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1207 | void **this_cache) | |
1208 | { | |
1209 | struct dwarf2_frame_cache *cache | |
1210 | = dwarf2_frame_cache (this_frame, this_cache); | |
1211 | ||
1212 | if (cache->unavailable_retaddr) | |
1213 | return UNWIND_UNAVAILABLE; | |
1214 | ||
1215 | if (cache->undefined_retaddr) | |
1216 | return UNWIND_OUTERMOST; | |
1217 | ||
1218 | return UNWIND_NO_REASON; | |
1219 | } | |
1220 | ||
cfc14b3a | 1221 | static void |
4a4e5149 | 1222 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1223 | struct frame_id *this_id) |
1224 | { | |
1225 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1226 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1227 | |
8fbca658 | 1228 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1229 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1230 | else if (cache->undefined_retaddr) | |
8fbca658 | 1231 | return; |
5ce0145d PA |
1232 | else |
1233 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1234 | } |
1235 | ||
4a4e5149 DJ |
1236 | static struct value * |
1237 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1238 | int regnum) | |
93d42b30 | 1239 | { |
4a4e5149 | 1240 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1241 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1242 | dwarf2_frame_cache (this_frame, this_cache); |
1243 | CORE_ADDR addr; | |
1244 | int realnum; | |
cfc14b3a | 1245 | |
1ec56e88 PA |
1246 | /* Check whether THIS_FRAME is the bottom frame of a virtual tail |
1247 | call frame chain. */ | |
1248 | if (!cache->checked_tailcall_bottom) | |
1249 | { | |
1250 | cache->checked_tailcall_bottom = 1; | |
1251 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, | |
1252 | (cache->entry_cfa_sp_offset_p | |
1253 | ? &cache->entry_cfa_sp_offset : NULL)); | |
1254 | } | |
1255 | ||
111c6489 JK |
1256 | /* Non-bottom frames of a virtual tail call frames chain use |
1257 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1258 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1259 | unwind the register, tail call frames are assumed to have the register set | |
1260 | of the top caller. */ | |
1261 | if (cache->tailcall_cache) | |
1262 | { | |
1263 | struct value *val; | |
1264 | ||
1265 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1266 | &cache->tailcall_cache, | |
1267 | regnum); | |
1268 | if (val) | |
1269 | return val; | |
1270 | } | |
1271 | ||
cfc14b3a MK |
1272 | switch (cache->reg[regnum].how) |
1273 | { | |
05cbe71a | 1274 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1275 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1276 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1277 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1278 | |
05cbe71a | 1279 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1280 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1281 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1282 | |
05cbe71a | 1283 | case DWARF2_FRAME_REG_SAVED_REG: |
0fde2c53 DE |
1284 | realnum = dwarf_reg_to_regnum_or_error |
1285 | (gdbarch, cache->reg[regnum].loc.reg); | |
4a4e5149 | 1286 | return frame_unwind_got_register (this_frame, regnum, realnum); |
cfc14b3a | 1287 | |
05cbe71a | 1288 | case DWARF2_FRAME_REG_SAVED_EXP: |
b348037f YQ |
1289 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1290 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1291 | cache->addr_size, cache->text_offset, |
1292 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1293 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1294 | |
46ea248b | 1295 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1296 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1297 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1298 | |
1299 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
b348037f YQ |
1300 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1301 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1302 | cache->addr_size, cache->text_offset, |
1303 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1304 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1305 | |
05cbe71a | 1306 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1307 | /* GCC, in its infinite wisdom decided to not provide unwind |
1308 | information for registers that are "same value". Since | |
1309 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1310 | registers are actually undefined (which is different to CFI | |
1311 | "undefined"). Code above issues a complaint about this. | |
1312 | Here just fudge the books, assume GCC, and that the value is | |
1313 | more inner on the stack. */ | |
4a4e5149 | 1314 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1315 | |
05cbe71a | 1316 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1317 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1318 | |
05cbe71a | 1319 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1320 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1321 | |
ea7963f0 | 1322 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1323 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1324 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1325 | |
8d5a9abc | 1326 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 | 1327 | addr = cache->reg[regnum].loc.offset; |
0fde2c53 | 1328 | regnum = dwarf_reg_to_regnum_or_error |
4a4e5149 DJ |
1329 | (gdbarch, cache->retaddr_reg.loc.reg); |
1330 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1331 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1332 | |
b39cc962 DJ |
1333 | case DWARF2_FRAME_REG_FN: |
1334 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1335 | ||
cfc14b3a | 1336 | default: |
e2e0b3e5 | 1337 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1338 | } |
1339 | } | |
1340 | ||
111c6489 JK |
1341 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1342 | call frames chain. */ | |
1343 | ||
1344 | static void | |
1345 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1346 | { | |
1347 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1348 | ||
1349 | if (cache->tailcall_cache) | |
1350 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1351 | } | |
1352 | ||
4a4e5149 DJ |
1353 | static int |
1354 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1355 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1356 | { |
1ce5d6dd | 1357 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1358 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1359 | end up returning something past the end of this function's body. |
1360 | If the frame we're sniffing for is a signal frame whose start | |
1361 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1362 | extend one byte before its start address or we could potentially |
1363 | select the FDE of the previous function. */ | |
1364 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1365 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1366 | |
56c987f6 | 1367 | if (!fde) |
4a4e5149 | 1368 | return 0; |
3ed09a32 DJ |
1369 | |
1370 | /* On some targets, signal trampolines may have unwind information. | |
1371 | We need to recognize them so that we set the frame type | |
1372 | correctly. */ | |
1373 | ||
56c987f6 | 1374 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1375 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1376 | this_frame)) | |
1377 | return self->type == SIGTRAMP_FRAME; | |
1378 | ||
111c6489 JK |
1379 | if (self->type != NORMAL_FRAME) |
1380 | return 0; | |
1381 | ||
111c6489 | 1382 | return 1; |
4a4e5149 DJ |
1383 | } |
1384 | ||
1385 | static const struct frame_unwind dwarf2_frame_unwind = | |
1386 | { | |
1387 | NORMAL_FRAME, | |
8fbca658 | 1388 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1389 | dwarf2_frame_this_id, |
1390 | dwarf2_frame_prev_register, | |
1391 | NULL, | |
111c6489 JK |
1392 | dwarf2_frame_sniffer, |
1393 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1394 | }; |
1395 | ||
1396 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1397 | { | |
1398 | SIGTRAMP_FRAME, | |
8fbca658 | 1399 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1400 | dwarf2_frame_this_id, |
1401 | dwarf2_frame_prev_register, | |
1402 | NULL, | |
111c6489 JK |
1403 | dwarf2_frame_sniffer, |
1404 | ||
1405 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1406 | NULL | |
4a4e5149 | 1407 | }; |
cfc14b3a | 1408 | |
4a4e5149 DJ |
1409 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1410 | ||
1411 | void | |
1412 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1413 | { | |
111c6489 JK |
1414 | /* TAILCALL_FRAME must be first to find the record by |
1415 | dwarf2_tailcall_sniffer_first. */ | |
1416 | frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind); | |
1417 | ||
4a4e5149 DJ |
1418 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); |
1419 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1420 | } |
1421 | \f | |
1422 | ||
1423 | /* There is no explicitly defined relationship between the CFA and the | |
1424 | location of frame's local variables and arguments/parameters. | |
1425 | Therefore, frame base methods on this page should probably only be | |
1426 | used as a last resort, just to avoid printing total garbage as a | |
1427 | response to the "info frame" command. */ | |
1428 | ||
1429 | static CORE_ADDR | |
4a4e5149 | 1430 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1431 | { |
1432 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1433 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1434 | |
1435 | return cache->cfa; | |
1436 | } | |
1437 | ||
1438 | static const struct frame_base dwarf2_frame_base = | |
1439 | { | |
1440 | &dwarf2_frame_unwind, | |
1441 | dwarf2_frame_base_address, | |
1442 | dwarf2_frame_base_address, | |
1443 | dwarf2_frame_base_address | |
1444 | }; | |
1445 | ||
1446 | const struct frame_base * | |
4a4e5149 | 1447 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1448 | { |
4a4e5149 | 1449 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1450 | |
ac56253d | 1451 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1452 | return &dwarf2_frame_base; |
1453 | ||
1454 | return NULL; | |
1455 | } | |
e7802207 TT |
1456 | |
1457 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1458 | the DWARF unwinder. This is used to implement | |
1459 | DW_OP_call_frame_cfa. */ | |
1460 | ||
1461 | CORE_ADDR | |
1462 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1463 | { | |
0b722aec MM |
1464 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1465 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1466 | throw_error (NOT_AVAILABLE_ERROR, | |
1467 | _("cfa not available for record btrace target")); | |
1468 | ||
e7802207 TT |
1469 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1470 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1471 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1472 | throw_error (NOT_AVAILABLE_ERROR, | |
1473 | _("can't compute CFA for this frame: " | |
1474 | "required registers or memory are unavailable")); | |
14aba1ac JB |
1475 | |
1476 | if (get_frame_id (this_frame).stack_status != FID_STACK_VALID) | |
1477 | throw_error (NOT_AVAILABLE_ERROR, | |
1478 | _("can't compute CFA for this frame: " | |
1479 | "frame base not available")); | |
1480 | ||
e7802207 TT |
1481 | return get_frame_base (this_frame); |
1482 | } | |
cfc14b3a | 1483 | \f |
8f22cb90 | 1484 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1485 | |
cfc14b3a | 1486 | static unsigned int |
f664829e | 1487 | read_1_byte (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1488 | { |
852483bc | 1489 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1490 | } |
1491 | ||
1492 | static unsigned int | |
f664829e | 1493 | read_4_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1494 | { |
852483bc | 1495 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1496 | } |
1497 | ||
1498 | static ULONGEST | |
f664829e | 1499 | read_8_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1500 | { |
852483bc | 1501 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1502 | } |
1503 | ||
1504 | static ULONGEST | |
f664829e DE |
1505 | read_initial_length (bfd *abfd, const gdb_byte *buf, |
1506 | unsigned int *bytes_read_ptr) | |
cfc14b3a MK |
1507 | { |
1508 | LONGEST result; | |
1509 | ||
852483bc | 1510 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1511 | if (result == 0xffffffff) |
1512 | { | |
852483bc | 1513 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1514 | *bytes_read_ptr = 12; |
1515 | } | |
1516 | else | |
1517 | *bytes_read_ptr = 4; | |
1518 | ||
1519 | return result; | |
1520 | } | |
1521 | \f | |
1522 | ||
1523 | /* Pointer encoding helper functions. */ | |
1524 | ||
1525 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1526 | technical reasons, it encodes addresses in its FDE's in a different | |
1527 | way. Several "pointer encodings" are supported. The encoding | |
1528 | that's used for a particular FDE is determined by the 'R' | |
1529 | augmentation in the associated CIE. The argument of this | |
1530 | augmentation is a single byte. | |
1531 | ||
1532 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1533 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1534 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1535 | address should be interpreted (absolute, relative to the current | |
1536 | position in the FDE, ...). Bit 7, indicates that the address | |
1537 | should be dereferenced. */ | |
1538 | ||
852483bc | 1539 | static gdb_byte |
cfc14b3a MK |
1540 | encoding_for_size (unsigned int size) |
1541 | { | |
1542 | switch (size) | |
1543 | { | |
1544 | case 2: | |
1545 | return DW_EH_PE_udata2; | |
1546 | case 4: | |
1547 | return DW_EH_PE_udata4; | |
1548 | case 8: | |
1549 | return DW_EH_PE_udata8; | |
1550 | default: | |
e2e0b3e5 | 1551 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1552 | } |
1553 | } | |
1554 | ||
cfc14b3a | 1555 | static CORE_ADDR |
852483bc | 1556 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1557 | int ptr_len, const gdb_byte *buf, |
1558 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1559 | CORE_ADDR func_base) |
cfc14b3a | 1560 | { |
68f6cf99 | 1561 | ptrdiff_t offset; |
cfc14b3a MK |
1562 | CORE_ADDR base; |
1563 | ||
1564 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1565 | FDE's. */ | |
1566 | if (encoding & DW_EH_PE_indirect) | |
1567 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1568 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1569 | |
68f6cf99 MK |
1570 | *bytes_read_ptr = 0; |
1571 | ||
cfc14b3a MK |
1572 | switch (encoding & 0x70) |
1573 | { | |
1574 | case DW_EH_PE_absptr: | |
1575 | base = 0; | |
1576 | break; | |
1577 | case DW_EH_PE_pcrel: | |
f2fec864 | 1578 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1579 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1580 | break; |
0912c7f2 MK |
1581 | case DW_EH_PE_datarel: |
1582 | base = unit->dbase; | |
1583 | break; | |
0fd85043 CV |
1584 | case DW_EH_PE_textrel: |
1585 | base = unit->tbase; | |
1586 | break; | |
03ac2a74 | 1587 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1588 | base = func_base; |
03ac2a74 | 1589 | break; |
68f6cf99 MK |
1590 | case DW_EH_PE_aligned: |
1591 | base = 0; | |
852483bc | 1592 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1593 | if ((offset % ptr_len) != 0) |
1594 | { | |
1595 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1596 | buf += *bytes_read_ptr; | |
1597 | } | |
1598 | break; | |
cfc14b3a | 1599 | default: |
3e43a32a MS |
1600 | internal_error (__FILE__, __LINE__, |
1601 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1602 | } |
1603 | ||
b04de778 | 1604 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1605 | { |
1606 | encoding |= encoding_for_size (ptr_len); | |
1607 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1608 | encoding |= DW_EH_PE_signed; | |
1609 | } | |
cfc14b3a MK |
1610 | |
1611 | switch (encoding & 0x0f) | |
1612 | { | |
a81b10ae MK |
1613 | case DW_EH_PE_uleb128: |
1614 | { | |
9fccedf7 | 1615 | uint64_t value; |
0d45f56e | 1616 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1617 | |
f664829e | 1618 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1619 | return base + value; |
1620 | } | |
cfc14b3a | 1621 | case DW_EH_PE_udata2: |
68f6cf99 | 1622 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1623 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1624 | case DW_EH_PE_udata4: | |
68f6cf99 | 1625 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1626 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1627 | case DW_EH_PE_udata8: | |
68f6cf99 | 1628 | *bytes_read_ptr += 8; |
cfc14b3a | 1629 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1630 | case DW_EH_PE_sleb128: |
1631 | { | |
9fccedf7 | 1632 | int64_t value; |
0d45f56e | 1633 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1634 | |
f664829e | 1635 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1636 | return base + value; |
1637 | } | |
cfc14b3a | 1638 | case DW_EH_PE_sdata2: |
68f6cf99 | 1639 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1640 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1641 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1642 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1643 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1644 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1645 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1646 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1647 | default: | |
3e43a32a MS |
1648 | internal_error (__FILE__, __LINE__, |
1649 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1650 | } |
1651 | } | |
1652 | \f | |
1653 | ||
b01c8410 PP |
1654 | static int |
1655 | bsearch_cie_cmp (const void *key, const void *element) | |
cfc14b3a | 1656 | { |
b01c8410 PP |
1657 | ULONGEST cie_pointer = *(ULONGEST *) key; |
1658 | struct dwarf2_cie *cie = *(struct dwarf2_cie **) element; | |
cfc14b3a | 1659 | |
b01c8410 PP |
1660 | if (cie_pointer == cie->cie_pointer) |
1661 | return 0; | |
cfc14b3a | 1662 | |
b01c8410 PP |
1663 | return (cie_pointer < cie->cie_pointer) ? -1 : 1; |
1664 | } | |
1665 | ||
1666 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ | |
1667 | static struct dwarf2_cie * | |
1668 | find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer) | |
1669 | { | |
1670 | struct dwarf2_cie **p_cie; | |
cfc14b3a | 1671 | |
65a97ab3 PP |
1672 | /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to |
1673 | bsearch be non-NULL. */ | |
1674 | if (cie_table->entries == NULL) | |
1675 | { | |
1676 | gdb_assert (cie_table->num_entries == 0); | |
1677 | return NULL; | |
1678 | } | |
1679 | ||
9a3c8263 SM |
1680 | p_cie = ((struct dwarf2_cie **) |
1681 | bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries, | |
1682 | sizeof (cie_table->entries[0]), bsearch_cie_cmp)); | |
b01c8410 PP |
1683 | if (p_cie != NULL) |
1684 | return *p_cie; | |
cfc14b3a MK |
1685 | return NULL; |
1686 | } | |
1687 | ||
b01c8410 | 1688 | /* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */ |
cfc14b3a | 1689 | static void |
b01c8410 | 1690 | add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie) |
cfc14b3a | 1691 | { |
b01c8410 PP |
1692 | const int n = cie_table->num_entries; |
1693 | ||
1694 | gdb_assert (n < 1 | |
1695 | || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer); | |
1696 | ||
224c3ddb SM |
1697 | cie_table->entries |
1698 | = XRESIZEVEC (struct dwarf2_cie *, cie_table->entries, n + 1); | |
b01c8410 PP |
1699 | cie_table->entries[n] = cie; |
1700 | cie_table->num_entries = n + 1; | |
1701 | } | |
1702 | ||
1703 | static int | |
1704 | bsearch_fde_cmp (const void *key, const void *element) | |
1705 | { | |
1706 | CORE_ADDR seek_pc = *(CORE_ADDR *) key; | |
1707 | struct dwarf2_fde *fde = *(struct dwarf2_fde **) element; | |
9a619af0 | 1708 | |
b01c8410 PP |
1709 | if (seek_pc < fde->initial_location) |
1710 | return -1; | |
1711 | if (seek_pc < fde->initial_location + fde->address_range) | |
1712 | return 0; | |
1713 | return 1; | |
cfc14b3a MK |
1714 | } |
1715 | ||
1716 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1717 | inital location associated with it into *PC. */ | |
1718 | ||
1719 | static struct dwarf2_fde * | |
ac56253d | 1720 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a MK |
1721 | { |
1722 | struct objfile *objfile; | |
1723 | ||
1724 | ALL_OBJFILES (objfile) | |
1725 | { | |
b01c8410 PP |
1726 | struct dwarf2_fde_table *fde_table; |
1727 | struct dwarf2_fde **p_fde; | |
cfc14b3a | 1728 | CORE_ADDR offset; |
b01c8410 | 1729 | CORE_ADDR seek_pc; |
cfc14b3a | 1730 | |
9a3c8263 SM |
1731 | fde_table = ((struct dwarf2_fde_table *) |
1732 | objfile_data (objfile, dwarf2_frame_objfile_data)); | |
b01c8410 | 1733 | if (fde_table == NULL) |
be391dca TT |
1734 | { |
1735 | dwarf2_build_frame_info (objfile); | |
9a3c8263 SM |
1736 | fde_table = ((struct dwarf2_fde_table *) |
1737 | objfile_data (objfile, dwarf2_frame_objfile_data)); | |
be391dca TT |
1738 | } |
1739 | gdb_assert (fde_table != NULL); | |
1740 | ||
1741 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1742 | continue; |
1743 | ||
1744 | gdb_assert (objfile->section_offsets); | |
1745 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1746 | ||
b01c8410 PP |
1747 | gdb_assert (fde_table->num_entries > 0); |
1748 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1749 | continue; | |
1750 | ||
1751 | seek_pc = *pc - offset; | |
9a3c8263 SM |
1752 | p_fde = ((struct dwarf2_fde **) |
1753 | bsearch (&seek_pc, fde_table->entries, fde_table->num_entries, | |
1754 | sizeof (fde_table->entries[0]), bsearch_fde_cmp)); | |
b01c8410 PP |
1755 | if (p_fde != NULL) |
1756 | { | |
1757 | *pc = (*p_fde)->initial_location + offset; | |
ac56253d TT |
1758 | if (out_offset) |
1759 | *out_offset = offset; | |
b01c8410 PP |
1760 | return *p_fde; |
1761 | } | |
cfc14b3a | 1762 | } |
cfc14b3a MK |
1763 | return NULL; |
1764 | } | |
1765 | ||
b01c8410 | 1766 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1767 | static void |
b01c8410 | 1768 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1769 | { |
b01c8410 PP |
1770 | if (fde->address_range == 0) |
1771 | /* Discard useless FDEs. */ | |
1772 | return; | |
1773 | ||
1774 | fde_table->num_entries += 1; | |
224c3ddb SM |
1775 | fde_table->entries = XRESIZEVEC (struct dwarf2_fde *, fde_table->entries, |
1776 | fde_table->num_entries); | |
b01c8410 | 1777 | fde_table->entries[fde_table->num_entries - 1] = fde; |
cfc14b3a MK |
1778 | } |
1779 | ||
cfc14b3a | 1780 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1781 | |
8bd90839 FM |
1782 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1783 | or any of them. */ | |
1784 | ||
1785 | enum eh_frame_type | |
1786 | { | |
1787 | EH_CIE_TYPE_ID = 1 << 0, | |
1788 | EH_FDE_TYPE_ID = 1 << 1, | |
1789 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1790 | }; | |
1791 | ||
f664829e DE |
1792 | static const gdb_byte *decode_frame_entry (struct comp_unit *unit, |
1793 | const gdb_byte *start, | |
1794 | int eh_frame_p, | |
1795 | struct dwarf2_cie_table *cie_table, | |
1796 | struct dwarf2_fde_table *fde_table, | |
1797 | enum eh_frame_type entry_type); | |
8bd90839 FM |
1798 | |
1799 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1800 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1801 | |
f664829e DE |
1802 | static const gdb_byte * |
1803 | decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, | |
1804 | int eh_frame_p, | |
b01c8410 | 1805 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
1806 | struct dwarf2_fde_table *fde_table, |
1807 | enum eh_frame_type entry_type) | |
cfc14b3a | 1808 | { |
5e2b427d | 1809 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
f664829e | 1810 | const gdb_byte *buf, *end; |
cfc14b3a MK |
1811 | LONGEST length; |
1812 | unsigned int bytes_read; | |
6896c0c7 RH |
1813 | int dwarf64_p; |
1814 | ULONGEST cie_id; | |
cfc14b3a | 1815 | ULONGEST cie_pointer; |
9fccedf7 DE |
1816 | int64_t sleb128; |
1817 | uint64_t uleb128; | |
cfc14b3a | 1818 | |
6896c0c7 | 1819 | buf = start; |
cfc14b3a MK |
1820 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1821 | buf += bytes_read; | |
1822 | end = buf + length; | |
1823 | ||
0963b4bd | 1824 | /* Are we still within the section? */ |
6896c0c7 RH |
1825 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) |
1826 | return NULL; | |
1827 | ||
cfc14b3a MK |
1828 | if (length == 0) |
1829 | return end; | |
1830 | ||
6896c0c7 RH |
1831 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1832 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1833 | |
6896c0c7 | 1834 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1835 | if (eh_frame_p) |
1836 | cie_id = 0; | |
1837 | else if (dwarf64_p) | |
1838 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1839 | else |
1840 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1841 | |
1842 | if (dwarf64_p) | |
1843 | { | |
1844 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1845 | buf += 8; | |
1846 | } | |
1847 | else | |
1848 | { | |
1849 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1850 | buf += 4; | |
1851 | } | |
1852 | ||
1853 | if (cie_pointer == cie_id) | |
1854 | { | |
1855 | /* This is a CIE. */ | |
1856 | struct dwarf2_cie *cie; | |
1857 | char *augmentation; | |
28ba0b33 | 1858 | unsigned int cie_version; |
cfc14b3a | 1859 | |
8bd90839 FM |
1860 | /* Check that a CIE was expected. */ |
1861 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1862 | error (_("Found a CIE when not expecting it.")); | |
1863 | ||
cfc14b3a MK |
1864 | /* Record the offset into the .debug_frame section of this CIE. */ |
1865 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1866 | ||
1867 | /* Check whether we've already read it. */ | |
b01c8410 | 1868 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1869 | return end; |
1870 | ||
8d749320 | 1871 | cie = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_cie); |
cfc14b3a MK |
1872 | cie->initial_instructions = NULL; |
1873 | cie->cie_pointer = cie_pointer; | |
1874 | ||
1875 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1876 | depends on the target address size. */ |
1877 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1878 | |
56c987f6 AO |
1879 | /* We'll determine the final value later, but we need to |
1880 | initialize it conservatively. */ | |
1881 | cie->signal_frame = 0; | |
1882 | ||
cfc14b3a | 1883 | /* Check version number. */ |
28ba0b33 | 1884 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1885 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1886 | return NULL; |
303b6f5d | 1887 | cie->version = cie_version; |
cfc14b3a MK |
1888 | buf += 1; |
1889 | ||
1890 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1891 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1892 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1893 | |
303b6f5d DJ |
1894 | /* Ignore armcc augmentations. We only use them for quirks, |
1895 | and that doesn't happen until later. */ | |
61012eef | 1896 | if (startswith (augmentation, "armcc")) |
303b6f5d DJ |
1897 | augmentation += strlen (augmentation); |
1898 | ||
cfc14b3a MK |
1899 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1900 | following the augmentation string, so it must be handled | |
1901 | first. */ | |
1902 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1903 | { | |
1904 | /* Skip. */ | |
5e2b427d | 1905 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1906 | augmentation += 2; |
1907 | } | |
1908 | ||
2dc7f7b3 TT |
1909 | if (cie->version >= 4) |
1910 | { | |
1911 | /* FIXME: check that this is the same as from the CU header. */ | |
1912 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1913 | ++buf; | |
1914 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1915 | ++buf; | |
1916 | } | |
1917 | else | |
1918 | { | |
8da614df | 1919 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1920 | cie->segment_size = 0; |
1921 | } | |
8da614df CV |
1922 | /* Address values in .eh_frame sections are defined to have the |
1923 | target's pointer size. Watchout: This breaks frame info for | |
1924 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1925 | section exists as well. */ |
8da614df CV |
1926 | if (eh_frame_p) |
1927 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1928 | else | |
1929 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1930 | |
f664829e DE |
1931 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1932 | if (buf == NULL) | |
1933 | return NULL; | |
1934 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1935 | |
f664829e DE |
1936 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1937 | if (buf == NULL) | |
1938 | return NULL; | |
1939 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1940 | |
28ba0b33 PB |
1941 | if (cie_version == 1) |
1942 | { | |
1943 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1944 | ++buf; |
28ba0b33 PB |
1945 | } |
1946 | else | |
f664829e DE |
1947 | { |
1948 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1949 | if (buf == NULL) | |
1950 | return NULL; | |
1951 | cie->return_address_register = uleb128; | |
1952 | } | |
1953 | ||
4fc771b8 | 1954 | cie->return_address_register |
5e2b427d | 1955 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1956 | cie->return_address_register, |
1957 | eh_frame_p); | |
4bf8967c | 1958 | |
7131cb6e RH |
1959 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1960 | if (cie->saw_z_augmentation) | |
cfc14b3a | 1961 | { |
9fccedf7 | 1962 | uint64_t length; |
cfc14b3a | 1963 | |
f664829e DE |
1964 | buf = gdb_read_uleb128 (buf, end, &length); |
1965 | if (buf == NULL) | |
6896c0c7 | 1966 | return NULL; |
cfc14b3a MK |
1967 | cie->initial_instructions = buf + length; |
1968 | augmentation++; | |
1969 | } | |
1970 | ||
1971 | while (*augmentation) | |
1972 | { | |
1973 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1974 | if (*augmentation == 'L') | |
1975 | { | |
1976 | /* Skip. */ | |
1977 | buf++; | |
1978 | augmentation++; | |
1979 | } | |
1980 | ||
1981 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1982 | else if (*augmentation == 'R') | |
1983 | { | |
1984 | cie->encoding = *buf++; | |
1985 | augmentation++; | |
1986 | } | |
1987 | ||
1988 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1989 | else if (*augmentation == 'P') | |
1990 | { | |
1234d960 | 1991 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1992 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1993 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1994 | buf, &bytes_read, 0); |
f724bf08 | 1995 | buf += bytes_read; |
cfc14b3a MK |
1996 | augmentation++; |
1997 | } | |
1998 | ||
56c987f6 AO |
1999 | /* "S" indicates a signal frame, such that the return |
2000 | address must not be decremented to locate the call frame | |
2001 | info for the previous frame; it might even be the first | |
2002 | instruction of a function, so decrementing it would take | |
2003 | us to a different function. */ | |
2004 | else if (*augmentation == 'S') | |
2005 | { | |
2006 | cie->signal_frame = 1; | |
2007 | augmentation++; | |
2008 | } | |
2009 | ||
3e9a2e52 DJ |
2010 | /* Otherwise we have an unknown augmentation. Assume that either |
2011 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
2012 | else |
2013 | { | |
3e9a2e52 DJ |
2014 | if (cie->initial_instructions) |
2015 | buf = cie->initial_instructions; | |
cfc14b3a MK |
2016 | break; |
2017 | } | |
2018 | } | |
2019 | ||
2020 | cie->initial_instructions = buf; | |
2021 | cie->end = end; | |
b01c8410 | 2022 | cie->unit = unit; |
cfc14b3a | 2023 | |
b01c8410 | 2024 | add_cie (cie_table, cie); |
cfc14b3a MK |
2025 | } |
2026 | else | |
2027 | { | |
2028 | /* This is a FDE. */ | |
2029 | struct dwarf2_fde *fde; | |
3e29f34a | 2030 | CORE_ADDR addr; |
cfc14b3a | 2031 | |
8bd90839 FM |
2032 | /* Check that an FDE was expected. */ |
2033 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
2034 | error (_("Found an FDE when not expecting it.")); | |
2035 | ||
6896c0c7 RH |
2036 | /* In an .eh_frame section, the CIE pointer is the delta between the |
2037 | address within the FDE where the CIE pointer is stored and the | |
2038 | address of the CIE. Convert it to an offset into the .eh_frame | |
2039 | section. */ | |
cfc14b3a MK |
2040 | if (eh_frame_p) |
2041 | { | |
cfc14b3a MK |
2042 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
2043 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
2044 | } | |
2045 | ||
6896c0c7 RH |
2046 | /* In either case, validate the result is still within the section. */ |
2047 | if (cie_pointer >= unit->dwarf_frame_size) | |
2048 | return NULL; | |
2049 | ||
8d749320 | 2050 | fde = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_fde); |
b01c8410 | 2051 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2052 | if (fde->cie == NULL) |
2053 | { | |
2054 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
2055 | eh_frame_p, cie_table, fde_table, |
2056 | EH_CIE_TYPE_ID); | |
b01c8410 | 2057 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2058 | } |
2059 | ||
2060 | gdb_assert (fde->cie != NULL); | |
2061 | ||
3e29f34a MR |
2062 | addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
2063 | buf, &bytes_read, 0); | |
2064 | fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); | |
cfc14b3a MK |
2065 | buf += bytes_read; |
2066 | ||
2067 | fde->address_range = | |
ae0d2f24 | 2068 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 2069 | fde->cie->ptr_size, buf, &bytes_read, 0); |
3e29f34a MR |
2070 | addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); |
2071 | fde->address_range = addr - fde->initial_location; | |
cfc14b3a MK |
2072 | buf += bytes_read; |
2073 | ||
7131cb6e RH |
2074 | /* A 'z' augmentation in the CIE implies the presence of an |
2075 | augmentation field in the FDE as well. The only thing known | |
2076 | to be in here at present is the LSDA entry for EH. So we | |
2077 | can skip the whole thing. */ | |
2078 | if (fde->cie->saw_z_augmentation) | |
2079 | { | |
9fccedf7 | 2080 | uint64_t length; |
7131cb6e | 2081 | |
f664829e DE |
2082 | buf = gdb_read_uleb128 (buf, end, &length); |
2083 | if (buf == NULL) | |
2084 | return NULL; | |
2085 | buf += length; | |
6896c0c7 RH |
2086 | if (buf > end) |
2087 | return NULL; | |
7131cb6e RH |
2088 | } |
2089 | ||
cfc14b3a MK |
2090 | fde->instructions = buf; |
2091 | fde->end = end; | |
2092 | ||
4bf8967c AS |
2093 | fde->eh_frame_p = eh_frame_p; |
2094 | ||
b01c8410 | 2095 | add_fde (fde_table, fde); |
cfc14b3a MK |
2096 | } |
2097 | ||
2098 | return end; | |
2099 | } | |
6896c0c7 | 2100 | |
8bd90839 FM |
2101 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2102 | expect an FDE or a CIE. */ | |
2103 | ||
f664829e DE |
2104 | static const gdb_byte * |
2105 | decode_frame_entry (struct comp_unit *unit, const gdb_byte *start, | |
2106 | int eh_frame_p, | |
b01c8410 | 2107 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
2108 | struct dwarf2_fde_table *fde_table, |
2109 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2110 | { |
2111 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2112 | const gdb_byte *ret; |
6896c0c7 RH |
2113 | ptrdiff_t start_offset; |
2114 | ||
2115 | while (1) | |
2116 | { | |
b01c8410 | 2117 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
8bd90839 | 2118 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2119 | if (ret != NULL) |
2120 | break; | |
2121 | ||
2122 | /* We have corrupt input data of some form. */ | |
2123 | ||
2124 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2125 | and mismatches wrt padding and alignment of debug sections. */ | |
2126 | /* Note that there is no requirement in the standard for any | |
2127 | alignment at all in the frame unwind sections. Testing for | |
2128 | alignment before trying to interpret data would be incorrect. | |
2129 | ||
2130 | However, GCC traditionally arranged for frame sections to be | |
2131 | sized such that the FDE length and CIE fields happen to be | |
2132 | aligned (in theory, for performance). This, unfortunately, | |
2133 | was done with .align directives, which had the side effect of | |
2134 | forcing the section to be aligned by the linker. | |
2135 | ||
2136 | This becomes a problem when you have some other producer that | |
2137 | creates frame sections that are not as strictly aligned. That | |
2138 | produces a hole in the frame info that gets filled by the | |
2139 | linker with zeros. | |
2140 | ||
2141 | The GCC behaviour is arguably a bug, but it's effectively now | |
2142 | part of the ABI, so we're now stuck with it, at least at the | |
2143 | object file level. A smart linker may decide, in the process | |
2144 | of compressing duplicate CIE information, that it can rewrite | |
2145 | the entire output section without this extra padding. */ | |
2146 | ||
2147 | start_offset = start - unit->dwarf_frame_buffer; | |
2148 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2149 | { | |
2150 | start += 4 - (start_offset & 3); | |
2151 | workaround = ALIGN4; | |
2152 | continue; | |
2153 | } | |
2154 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2155 | { | |
2156 | start += 8 - (start_offset & 7); | |
2157 | workaround = ALIGN8; | |
2158 | continue; | |
2159 | } | |
2160 | ||
2161 | /* Nothing left to try. Arrange to return as if we've consumed | |
2162 | the entire input section. Hopefully we'll get valid info from | |
2163 | the other of .debug_frame/.eh_frame. */ | |
2164 | workaround = FAIL; | |
2165 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2166 | break; | |
2167 | } | |
2168 | ||
2169 | switch (workaround) | |
2170 | { | |
2171 | case NONE: | |
2172 | break; | |
2173 | ||
2174 | case ALIGN4: | |
3e43a32a MS |
2175 | complaint (&symfile_complaints, _("\ |
2176 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), | |
6896c0c7 RH |
2177 | unit->dwarf_frame_section->owner->filename, |
2178 | unit->dwarf_frame_section->name); | |
2179 | break; | |
2180 | ||
2181 | case ALIGN8: | |
3e43a32a MS |
2182 | complaint (&symfile_complaints, _("\ |
2183 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), | |
6896c0c7 RH |
2184 | unit->dwarf_frame_section->owner->filename, |
2185 | unit->dwarf_frame_section->name); | |
2186 | break; | |
2187 | ||
2188 | default: | |
2189 | complaint (&symfile_complaints, | |
e2e0b3e5 | 2190 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
2191 | unit->dwarf_frame_section->owner->filename, |
2192 | unit->dwarf_frame_section->name); | |
2193 | break; | |
2194 | } | |
2195 | ||
2196 | return ret; | |
2197 | } | |
cfc14b3a | 2198 | \f |
b01c8410 PP |
2199 | static int |
2200 | qsort_fde_cmp (const void *a, const void *b) | |
2201 | { | |
2202 | struct dwarf2_fde *aa = *(struct dwarf2_fde **)a; | |
2203 | struct dwarf2_fde *bb = *(struct dwarf2_fde **)b; | |
e5af178f | 2204 | |
b01c8410 | 2205 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2206 | { |
2207 | if (aa->address_range != bb->address_range | |
2208 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2209 | /* Linker bug, e.g. gold/10400. | |
2210 | Work around it by keeping stable sort order. */ | |
2211 | return (a < b) ? -1 : 1; | |
2212 | else | |
2213 | /* Put eh_frame entries after debug_frame ones. */ | |
2214 | return aa->eh_frame_p - bb->eh_frame_p; | |
2215 | } | |
b01c8410 PP |
2216 | |
2217 | return (aa->initial_location < bb->initial_location) ? -1 : 1; | |
2218 | } | |
2219 | ||
cfc14b3a MK |
2220 | void |
2221 | dwarf2_build_frame_info (struct objfile *objfile) | |
2222 | { | |
ae0d2f24 | 2223 | struct comp_unit *unit; |
f664829e | 2224 | const gdb_byte *frame_ptr; |
b01c8410 PP |
2225 | struct dwarf2_cie_table cie_table; |
2226 | struct dwarf2_fde_table fde_table; | |
be391dca | 2227 | struct dwarf2_fde_table *fde_table2; |
b01c8410 PP |
2228 | |
2229 | cie_table.num_entries = 0; | |
2230 | cie_table.entries = NULL; | |
2231 | ||
2232 | fde_table.num_entries = 0; | |
2233 | fde_table.entries = NULL; | |
cfc14b3a MK |
2234 | |
2235 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
ae0d2f24 UW |
2236 | unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack, |
2237 | sizeof (struct comp_unit)); | |
2238 | unit->abfd = objfile->obfd; | |
2239 | unit->objfile = objfile; | |
2240 | unit->dbase = 0; | |
2241 | unit->tbase = 0; | |
cfc14b3a | 2242 | |
d40102a1 | 2243 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2244 | { |
d40102a1 JB |
2245 | /* Do not read .eh_frame from separate file as they must be also |
2246 | present in the main file. */ | |
2247 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, | |
2248 | &unit->dwarf_frame_section, | |
2249 | &unit->dwarf_frame_buffer, | |
2250 | &unit->dwarf_frame_size); | |
2251 | if (unit->dwarf_frame_size) | |
b01c8410 | 2252 | { |
d40102a1 JB |
2253 | asection *got, *txt; |
2254 | ||
2255 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2256 | that is used for the i386/amd64 target, which currently is | |
2257 | the only target in GCC that supports/uses the | |
2258 | DW_EH_PE_datarel encoding. */ | |
2259 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2260 | if (got) | |
2261 | unit->dbase = got->vma; | |
2262 | ||
2263 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2264 | so far. */ | |
2265 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2266 | if (txt) | |
2267 | unit->tbase = txt->vma; | |
2268 | ||
492d29ea | 2269 | TRY |
8bd90839 FM |
2270 | { |
2271 | frame_ptr = unit->dwarf_frame_buffer; | |
2272 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2273 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, | |
2274 | &cie_table, &fde_table, | |
2275 | EH_CIE_OR_FDE_TYPE_ID); | |
2276 | } | |
2277 | ||
492d29ea | 2278 | CATCH (e, RETURN_MASK_ERROR) |
8bd90839 FM |
2279 | { |
2280 | warning (_("skipping .eh_frame info of %s: %s"), | |
4262abfb | 2281 | objfile_name (objfile), e.message); |
8bd90839 FM |
2282 | |
2283 | if (fde_table.num_entries != 0) | |
2284 | { | |
2285 | xfree (fde_table.entries); | |
2286 | fde_table.entries = NULL; | |
2287 | fde_table.num_entries = 0; | |
2288 | } | |
2289 | /* The cie_table is discarded by the next if. */ | |
2290 | } | |
492d29ea | 2291 | END_CATCH |
d40102a1 JB |
2292 | |
2293 | if (cie_table.num_entries != 0) | |
2294 | { | |
2295 | /* Reinit cie_table: debug_frame has different CIEs. */ | |
2296 | xfree (cie_table.entries); | |
2297 | cie_table.num_entries = 0; | |
2298 | cie_table.entries = NULL; | |
2299 | } | |
b01c8410 | 2300 | } |
cfc14b3a MK |
2301 | } |
2302 | ||
3017a003 | 2303 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dce234bc PP |
2304 | &unit->dwarf_frame_section, |
2305 | &unit->dwarf_frame_buffer, | |
2306 | &unit->dwarf_frame_size); | |
2307 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2308 | { |
8bd90839 FM |
2309 | int num_old_fde_entries = fde_table.num_entries; |
2310 | ||
492d29ea | 2311 | TRY |
8bd90839 FM |
2312 | { |
2313 | frame_ptr = unit->dwarf_frame_buffer; | |
2314 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2315 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, | |
2316 | &cie_table, &fde_table, | |
2317 | EH_CIE_OR_FDE_TYPE_ID); | |
2318 | } | |
492d29ea | 2319 | CATCH (e, RETURN_MASK_ERROR) |
8bd90839 FM |
2320 | { |
2321 | warning (_("skipping .debug_frame info of %s: %s"), | |
4262abfb | 2322 | objfile_name (objfile), e.message); |
8bd90839 FM |
2323 | |
2324 | if (fde_table.num_entries != 0) | |
2325 | { | |
2326 | fde_table.num_entries = num_old_fde_entries; | |
2327 | if (num_old_fde_entries == 0) | |
2328 | { | |
2329 | xfree (fde_table.entries); | |
2330 | fde_table.entries = NULL; | |
2331 | } | |
2332 | else | |
2333 | { | |
224c3ddb SM |
2334 | fde_table.entries |
2335 | = XRESIZEVEC (struct dwarf2_fde *, fde_table.entries, | |
2336 | fde_table.num_entries); | |
8bd90839 FM |
2337 | } |
2338 | } | |
2339 | fde_table.num_entries = num_old_fde_entries; | |
2340 | /* The cie_table is discarded by the next if. */ | |
2341 | } | |
492d29ea | 2342 | END_CATCH |
b01c8410 PP |
2343 | } |
2344 | ||
2345 | /* Discard the cie_table, it is no longer needed. */ | |
2346 | if (cie_table.num_entries != 0) | |
2347 | { | |
2348 | xfree (cie_table.entries); | |
2349 | cie_table.entries = NULL; /* Paranoia. */ | |
2350 | cie_table.num_entries = 0; /* Paranoia. */ | |
2351 | } | |
2352 | ||
be391dca | 2353 | /* Copy fde_table to obstack: it is needed at runtime. */ |
8d749320 | 2354 | fde_table2 = XOBNEW (&objfile->objfile_obstack, struct dwarf2_fde_table); |
be391dca TT |
2355 | |
2356 | if (fde_table.num_entries == 0) | |
2357 | { | |
2358 | fde_table2->entries = NULL; | |
2359 | fde_table2->num_entries = 0; | |
2360 | } | |
2361 | else | |
b01c8410 | 2362 | { |
875cdfbb PA |
2363 | struct dwarf2_fde *fde_prev = NULL; |
2364 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2365 | int i; | |
b01c8410 PP |
2366 | |
2367 | /* Prepare FDE table for lookups. */ | |
2368 | qsort (fde_table.entries, fde_table.num_entries, | |
2369 | sizeof (fde_table.entries[0]), qsort_fde_cmp); | |
2370 | ||
875cdfbb PA |
2371 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2372 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2373 | ranges because there's no relocation there. It's (offset, | |
2374 | length), not (start, end). On targets where address zero is | |
2375 | just another valid address this can be a problem, since the | |
2376 | FDEs appear to be non-empty in the output --- we could pick | |
2377 | out the wrong FDE. To work around this, when overlaps are | |
2378 | detected, we prefer FDEs that do not start at zero. | |
2379 | ||
2380 | Start by finding the first FDE with non-zero start. Below | |
2381 | we'll discard all FDEs that start at zero and overlap this | |
2382 | one. */ | |
2383 | for (i = 0; i < fde_table.num_entries; i++) | |
2384 | { | |
2385 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2386 | |
875cdfbb PA |
2387 | if (fde->initial_location != 0) |
2388 | { | |
2389 | first_non_zero_fde = fde; | |
2390 | break; | |
2391 | } | |
2392 | } | |
2393 | ||
2394 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2395 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2396 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2397 | fde_table2->num_entries = 0; |
875cdfbb PA |
2398 | for (i = 0; i < fde_table.num_entries; i++) |
2399 | { | |
2400 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2401 | ||
2402 | if (fde->initial_location == 0 | |
2403 | && first_non_zero_fde != NULL | |
2404 | && (first_non_zero_fde->initial_location | |
2405 | < fde->initial_location + fde->address_range)) | |
2406 | continue; | |
2407 | ||
2408 | if (fde_prev != NULL | |
2409 | && fde_prev->initial_location == fde->initial_location) | |
2410 | continue; | |
2411 | ||
2412 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2413 | sizeof (fde_table.entries[0])); | |
2414 | ++fde_table2->num_entries; | |
2415 | fde_prev = fde; | |
2416 | } | |
224c3ddb SM |
2417 | fde_table2->entries |
2418 | = (struct dwarf2_fde **) obstack_finish (&objfile->objfile_obstack); | |
b01c8410 PP |
2419 | |
2420 | /* Discard the original fde_table. */ | |
2421 | xfree (fde_table.entries); | |
cfc14b3a | 2422 | } |
be391dca TT |
2423 | |
2424 | set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2); | |
cfc14b3a | 2425 | } |
0d0e1a63 MK |
2426 | |
2427 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
2428 | void _initialize_dwarf2_frame (void); | |
2429 | ||
2430 | void | |
2431 | _initialize_dwarf2_frame (void) | |
2432 | { | |
030f20e1 | 2433 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2434 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 2435 | } |