Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
e2882c85 | 3 | Copyright (C) 2003-2018 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" |
3c3bb058 | 38 | #include "dwarf2read.h" |
9f6f94ff TT |
39 | #include "ax.h" |
40 | #include "dwarf2loc.h" | |
111c6489 | 41 | #include "dwarf2-frame-tailcall.h" |
1c90d9f0 YQ |
42 | #if GDB_SELF_TEST |
43 | #include "selftest.h" | |
44 | #include "selftest-arch.h" | |
45 | #endif | |
cfc14b3a | 46 | |
ae0d2f24 UW |
47 | struct comp_unit; |
48 | ||
cfc14b3a MK |
49 | /* Call Frame Information (CFI). */ |
50 | ||
51 | /* Common Information Entry (CIE). */ | |
52 | ||
53 | struct dwarf2_cie | |
54 | { | |
ae0d2f24 UW |
55 | /* Computation Unit for this CIE. */ |
56 | struct comp_unit *unit; | |
57 | ||
cfc14b3a MK |
58 | /* Offset into the .debug_frame section where this CIE was found. |
59 | Used to identify this CIE. */ | |
60 | ULONGEST cie_pointer; | |
61 | ||
62 | /* Constant that is factored out of all advance location | |
63 | instructions. */ | |
64 | ULONGEST code_alignment_factor; | |
65 | ||
66 | /* Constants that is factored out of all offset instructions. */ | |
67 | LONGEST data_alignment_factor; | |
68 | ||
69 | /* Return address column. */ | |
70 | ULONGEST return_address_register; | |
71 | ||
72 | /* Instruction sequence to initialize a register set. */ | |
f664829e DE |
73 | const gdb_byte *initial_instructions; |
74 | const gdb_byte *end; | |
cfc14b3a | 75 | |
303b6f5d DJ |
76 | /* Saved augmentation, in case it's needed later. */ |
77 | char *augmentation; | |
78 | ||
cfc14b3a | 79 | /* Encoding of addresses. */ |
852483bc | 80 | gdb_byte encoding; |
cfc14b3a | 81 | |
ae0d2f24 UW |
82 | /* Target address size in bytes. */ |
83 | int addr_size; | |
84 | ||
0963b4bd | 85 | /* Target pointer size in bytes. */ |
8da614df CV |
86 | int ptr_size; |
87 | ||
7131cb6e RH |
88 | /* True if a 'z' augmentation existed. */ |
89 | unsigned char saw_z_augmentation; | |
90 | ||
56c987f6 AO |
91 | /* True if an 'S' augmentation existed. */ |
92 | unsigned char signal_frame; | |
93 | ||
303b6f5d DJ |
94 | /* The version recorded in the CIE. */ |
95 | unsigned char version; | |
2dc7f7b3 TT |
96 | |
97 | /* The segment size. */ | |
98 | unsigned char segment_size; | |
b01c8410 | 99 | }; |
303b6f5d | 100 | |
b01c8410 PP |
101 | struct dwarf2_cie_table |
102 | { | |
103 | int num_entries; | |
104 | struct dwarf2_cie **entries; | |
cfc14b3a MK |
105 | }; |
106 | ||
107 | /* Frame Description Entry (FDE). */ | |
108 | ||
109 | struct dwarf2_fde | |
110 | { | |
111 | /* CIE for this FDE. */ | |
112 | struct dwarf2_cie *cie; | |
113 | ||
114 | /* First location associated with this FDE. */ | |
115 | CORE_ADDR initial_location; | |
116 | ||
117 | /* Number of bytes of program instructions described by this FDE. */ | |
118 | CORE_ADDR address_range; | |
119 | ||
120 | /* Instruction sequence. */ | |
f664829e DE |
121 | const gdb_byte *instructions; |
122 | const gdb_byte *end; | |
cfc14b3a | 123 | |
4bf8967c AS |
124 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
125 | section. */ | |
126 | unsigned char eh_frame_p; | |
b01c8410 | 127 | }; |
4bf8967c | 128 | |
b01c8410 PP |
129 | struct dwarf2_fde_table |
130 | { | |
131 | int num_entries; | |
132 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
133 | }; |
134 | ||
ae0d2f24 UW |
135 | /* A minimal decoding of DWARF2 compilation units. We only decode |
136 | what's needed to get to the call frame information. */ | |
137 | ||
138 | struct comp_unit | |
139 | { | |
140 | /* Keep the bfd convenient. */ | |
141 | bfd *abfd; | |
142 | ||
143 | struct objfile *objfile; | |
144 | ||
ae0d2f24 | 145 | /* Pointer to the .debug_frame section loaded into memory. */ |
d521ce57 | 146 | const gdb_byte *dwarf_frame_buffer; |
ae0d2f24 UW |
147 | |
148 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 149 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
150 | |
151 | /* Pointer to the .debug_frame section. */ | |
152 | asection *dwarf_frame_section; | |
153 | ||
154 | /* Base for DW_EH_PE_datarel encodings. */ | |
155 | bfd_vma dbase; | |
156 | ||
157 | /* Base for DW_EH_PE_textrel encodings. */ | |
158 | bfd_vma tbase; | |
159 | }; | |
160 | ||
ac56253d TT |
161 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
162 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
163 | |
164 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
165 | int eh_frame_p); | |
ae0d2f24 UW |
166 | |
167 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 168 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
169 | unsigned int *bytes_read_ptr, |
170 | CORE_ADDR func_base); | |
cfc14b3a MK |
171 | \f |
172 | ||
3c3bb058 AB |
173 | /* See dwarf2-frame.h. */ |
174 | int dwarf2_frame_unwinders_enabled_p = 1; | |
175 | ||
cfc14b3a MK |
176 | /* Store the length the expression for the CFA in the `cfa_reg' field, |
177 | which is unused in that case. */ | |
178 | #define cfa_exp_len cfa_reg | |
179 | ||
afe37d6b YQ |
180 | dwarf2_frame_state::dwarf2_frame_state (CORE_ADDR pc_, struct dwarf2_cie *cie) |
181 | : pc (pc_), data_align (cie->data_alignment_factor), | |
182 | code_align (cie->code_alignment_factor), | |
183 | retaddr_column (cie->return_address_register) | |
cfc14b3a | 184 | { |
afe37d6b | 185 | } |
cfc14b3a MK |
186 | \f |
187 | ||
188 | /* Helper functions for execute_stack_op. */ | |
189 | ||
190 | static CORE_ADDR | |
192ca6d8 | 191 | read_addr_from_reg (struct frame_info *this_frame, int reg) |
cfc14b3a | 192 | { |
4a4e5149 | 193 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
0fde2c53 | 194 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); |
f2da6b3a | 195 | |
2ed3c037 | 196 | return address_from_register (regnum, this_frame); |
cfc14b3a MK |
197 | } |
198 | ||
a6a5a945 LM |
199 | /* Execute the required actions for both the DW_CFA_restore and |
200 | DW_CFA_restore_extended instructions. */ | |
201 | static void | |
202 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
203 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
204 | { | |
205 | ULONGEST reg; | |
206 | ||
207 | gdb_assert (fs->initial.reg); | |
208 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); | |
1c90d9f0 | 209 | fs->regs.alloc_regs (reg + 1); |
a6a5a945 LM |
210 | |
211 | /* Check if this register was explicitly initialized in the | |
212 | CIE initial instructions. If not, default the rule to | |
213 | UNSPECIFIED. */ | |
214 | if (reg < fs->initial.num_regs) | |
215 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
216 | else | |
217 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
218 | ||
219 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
0fde2c53 DE |
220 | { |
221 | int regnum = dwarf_reg_to_regnum (gdbarch, reg); | |
222 | ||
b98664d3 | 223 | complaint (_("\ |
a6a5a945 | 224 | incomplete CFI data; DW_CFA_restore unspecified\n\ |
5af949e3 | 225 | register %s (#%d) at %s"), |
0fde2c53 DE |
226 | gdbarch_register_name (gdbarch, regnum), regnum, |
227 | paddress (gdbarch, fs->pc)); | |
228 | } | |
a6a5a945 LM |
229 | } |
230 | ||
192ca6d8 | 231 | class dwarf_expr_executor : public dwarf_expr_context |
9e8b7a03 | 232 | { |
192ca6d8 TT |
233 | public: |
234 | ||
235 | struct frame_info *this_frame; | |
236 | ||
632e107b | 237 | CORE_ADDR read_addr_from_reg (int reg) override |
192ca6d8 TT |
238 | { |
239 | return ::read_addr_from_reg (this_frame, reg); | |
240 | } | |
241 | ||
632e107b | 242 | struct value *get_reg_value (struct type *type, int reg) override |
192ca6d8 TT |
243 | { |
244 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
245 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); | |
246 | ||
247 | return value_from_register (type, regnum, this_frame); | |
248 | } | |
249 | ||
632e107b | 250 | void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) override |
192ca6d8 TT |
251 | { |
252 | read_memory (addr, buf, len); | |
253 | } | |
befbff86 | 254 | |
632e107b | 255 | void get_frame_base (const gdb_byte **start, size_t *length) override |
befbff86 TT |
256 | { |
257 | invalid ("DW_OP_fbreg"); | |
258 | } | |
259 | ||
260 | void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, | |
261 | union call_site_parameter_u kind_u, | |
632e107b | 262 | int deref_size) override |
befbff86 | 263 | { |
216f72a1 | 264 | invalid ("DW_OP_entry_value"); |
befbff86 TT |
265 | } |
266 | ||
632e107b | 267 | CORE_ADDR get_object_address () override |
befbff86 TT |
268 | { |
269 | invalid ("DW_OP_push_object_address"); | |
270 | } | |
271 | ||
632e107b | 272 | CORE_ADDR get_frame_cfa () override |
befbff86 TT |
273 | { |
274 | invalid ("DW_OP_call_frame_cfa"); | |
275 | } | |
276 | ||
632e107b | 277 | CORE_ADDR get_tls_address (CORE_ADDR offset) override |
befbff86 TT |
278 | { |
279 | invalid ("DW_OP_form_tls_address"); | |
280 | } | |
281 | ||
632e107b | 282 | void dwarf_call (cu_offset die_offset) override |
befbff86 TT |
283 | { |
284 | invalid ("DW_OP_call*"); | |
285 | } | |
286 | ||
632e107b | 287 | CORE_ADDR get_addr_index (unsigned int index) override |
befbff86 TT |
288 | { |
289 | invalid ("DW_OP_GNU_addr_index"); | |
290 | } | |
291 | ||
292 | private: | |
293 | ||
294 | void invalid (const char *op) ATTRIBUTE_NORETURN | |
295 | { | |
296 | error (_("%s is invalid in this context"), op); | |
297 | } | |
9e8b7a03 JK |
298 | }; |
299 | ||
cfc14b3a | 300 | static CORE_ADDR |
0d45f56e | 301 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
302 | CORE_ADDR offset, struct frame_info *this_frame, |
303 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a | 304 | { |
cfc14b3a MK |
305 | CORE_ADDR result; |
306 | ||
192ca6d8 | 307 | dwarf_expr_executor ctx; |
eb115069 | 308 | scoped_value_mark free_values; |
4a227398 | 309 | |
192ca6d8 | 310 | ctx.this_frame = this_frame; |
718b9626 TT |
311 | ctx.gdbarch = get_frame_arch (this_frame); |
312 | ctx.addr_size = addr_size; | |
313 | ctx.ref_addr_size = -1; | |
314 | ctx.offset = offset; | |
cfc14b3a | 315 | |
595d2e30 TT |
316 | ctx.push_address (initial, initial_in_stack_memory); |
317 | ctx.eval (exp, len); | |
cfc14b3a | 318 | |
718b9626 | 319 | if (ctx.location == DWARF_VALUE_MEMORY) |
595d2e30 | 320 | result = ctx.fetch_address (0); |
718b9626 | 321 | else if (ctx.location == DWARF_VALUE_REGISTER) |
192ca6d8 | 322 | result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0))); |
f2c7657e | 323 | else |
cec03d70 TT |
324 | { |
325 | /* This is actually invalid DWARF, but if we ever do run across | |
326 | it somehow, we might as well support it. So, instead, report | |
327 | it as unimplemented. */ | |
3e43a32a MS |
328 | error (_("\ |
329 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 330 | } |
cfc14b3a | 331 | |
cfc14b3a MK |
332 | return result; |
333 | } | |
334 | \f | |
335 | ||
111c6489 JK |
336 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
337 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
338 | execution has stopped, one can resume it on the next call. */ | |
339 | ||
340 | static const gdb_byte * | |
0d45f56e | 341 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff TT |
342 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
343 | CORE_ADDR pc, struct dwarf2_frame_state *fs) | |
cfc14b3a | 344 | { |
ae0d2f24 | 345 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 346 | unsigned int bytes_read; |
e17a4113 | 347 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
348 | |
349 | while (insn_ptr < insn_end && fs->pc <= pc) | |
350 | { | |
852483bc | 351 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
352 | uint64_t utmp, reg; |
353 | int64_t offset; | |
cfc14b3a MK |
354 | |
355 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
356 | fs->pc += (insn & 0x3f) * fs->code_align; | |
357 | else if ((insn & 0xc0) == DW_CFA_offset) | |
358 | { | |
359 | reg = insn & 0x3f; | |
4fc771b8 | 360 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 361 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 362 | offset = utmp * fs->data_align; |
1c90d9f0 | 363 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 364 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
365 | fs->regs.reg[reg].loc.offset = offset; |
366 | } | |
367 | else if ((insn & 0xc0) == DW_CFA_restore) | |
368 | { | |
cfc14b3a | 369 | reg = insn & 0x3f; |
a6a5a945 | 370 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
371 | } |
372 | else | |
373 | { | |
374 | switch (insn) | |
375 | { | |
376 | case DW_CFA_set_loc: | |
ae0d2f24 | 377 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 378 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
379 | &bytes_read, fde->initial_location); |
380 | /* Apply the objfile offset for relocatable objects. */ | |
381 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
382 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
383 | insn_ptr += bytes_read; |
384 | break; | |
385 | ||
386 | case DW_CFA_advance_loc1: | |
e17a4113 | 387 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
388 | fs->pc += utmp * fs->code_align; |
389 | insn_ptr++; | |
390 | break; | |
391 | case DW_CFA_advance_loc2: | |
e17a4113 | 392 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
393 | fs->pc += utmp * fs->code_align; |
394 | insn_ptr += 2; | |
395 | break; | |
396 | case DW_CFA_advance_loc4: | |
e17a4113 | 397 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
398 | fs->pc += utmp * fs->code_align; |
399 | insn_ptr += 4; | |
400 | break; | |
401 | ||
402 | case DW_CFA_offset_extended: | |
f664829e | 403 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 404 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 405 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 406 | offset = utmp * fs->data_align; |
1c90d9f0 | 407 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 408 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
409 | fs->regs.reg[reg].loc.offset = offset; |
410 | break; | |
411 | ||
412 | case DW_CFA_restore_extended: | |
f664829e | 413 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 414 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
415 | break; |
416 | ||
417 | case DW_CFA_undefined: | |
f664829e | 418 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 419 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 420 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 421 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
422 | break; |
423 | ||
424 | case DW_CFA_same_value: | |
f664829e | 425 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 426 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 427 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 428 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
429 | break; |
430 | ||
431 | case DW_CFA_register: | |
f664829e | 432 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 433 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 434 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 435 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
1c90d9f0 | 436 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 437 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
438 | fs->regs.reg[reg].loc.reg = utmp; |
439 | break; | |
440 | ||
441 | case DW_CFA_remember_state: | |
442 | { | |
443 | struct dwarf2_frame_state_reg_info *new_rs; | |
444 | ||
1c90d9f0 | 445 | new_rs = new dwarf2_frame_state_reg_info (fs->regs); |
cfc14b3a MK |
446 | fs->regs.prev = new_rs; |
447 | } | |
448 | break; | |
449 | ||
450 | case DW_CFA_restore_state: | |
451 | { | |
452 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
453 | ||
50ea7769 MK |
454 | if (old_rs == NULL) |
455 | { | |
b98664d3 | 456 | complaint (_("\ |
5af949e3 UW |
457 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
458 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
459 | } |
460 | else | |
1c90d9f0 | 461 | fs->regs = std::move (*old_rs); |
cfc14b3a MK |
462 | } |
463 | break; | |
464 | ||
465 | case DW_CFA_def_cfa: | |
f664829e DE |
466 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
467 | fs->regs.cfa_reg = reg; | |
468 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
469 | |
470 | if (fs->armcc_cfa_offsets_sf) | |
471 | utmp *= fs->data_align; | |
472 | ||
2fd481e1 PP |
473 | fs->regs.cfa_offset = utmp; |
474 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
475 | break; |
476 | ||
477 | case DW_CFA_def_cfa_register: | |
f664829e DE |
478 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
479 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 PP |
480 | eh_frame_p); |
481 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
482 | break; |
483 | ||
484 | case DW_CFA_def_cfa_offset: | |
f664829e | 485 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
486 | |
487 | if (fs->armcc_cfa_offsets_sf) | |
488 | utmp *= fs->data_align; | |
489 | ||
2fd481e1 | 490 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
491 | /* cfa_how deliberately not set. */ |
492 | break; | |
493 | ||
a8504492 MK |
494 | case DW_CFA_nop: |
495 | break; | |
496 | ||
cfc14b3a | 497 | case DW_CFA_def_cfa_expression: |
f664829e DE |
498 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
499 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
500 | fs->regs.cfa_exp = insn_ptr; |
501 | fs->regs.cfa_how = CFA_EXP; | |
502 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
503 | break; |
504 | ||
505 | case DW_CFA_expression: | |
f664829e | 506 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 507 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 508 | fs->regs.alloc_regs (reg + 1); |
f664829e | 509 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
510 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
511 | fs->regs.reg[reg].loc.exp.len = utmp; | |
05cbe71a | 512 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
513 | insn_ptr += utmp; |
514 | break; | |
515 | ||
a8504492 | 516 | case DW_CFA_offset_extended_sf: |
f664829e | 517 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 518 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 519 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 520 | offset *= fs->data_align; |
1c90d9f0 | 521 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 522 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
523 | fs->regs.reg[reg].loc.offset = offset; |
524 | break; | |
525 | ||
46ea248b | 526 | case DW_CFA_val_offset: |
f664829e | 527 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 528 | fs->regs.alloc_regs (reg + 1); |
f664829e | 529 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
530 | offset = utmp * fs->data_align; |
531 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
532 | fs->regs.reg[reg].loc.offset = offset; | |
533 | break; | |
534 | ||
535 | case DW_CFA_val_offset_sf: | |
f664829e | 536 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 537 | fs->regs.alloc_regs (reg + 1); |
f664829e | 538 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
539 | offset *= fs->data_align; |
540 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
541 | fs->regs.reg[reg].loc.offset = offset; | |
542 | break; | |
543 | ||
544 | case DW_CFA_val_expression: | |
f664829e | 545 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 546 | fs->regs.alloc_regs (reg + 1); |
f664829e | 547 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
548 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
549 | fs->regs.reg[reg].loc.exp.len = utmp; | |
46ea248b AO |
550 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; |
551 | insn_ptr += utmp; | |
552 | break; | |
553 | ||
a8504492 | 554 | case DW_CFA_def_cfa_sf: |
f664829e DE |
555 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
556 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 | 557 | eh_frame_p); |
f664829e | 558 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
559 | fs->regs.cfa_offset = offset * fs->data_align; |
560 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
561 | break; |
562 | ||
563 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 564 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 565 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 566 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
567 | break; |
568 | ||
569 | case DW_CFA_GNU_args_size: | |
570 | /* Ignored. */ | |
f664829e | 571 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
572 | break; |
573 | ||
58894217 | 574 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 575 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 576 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
577 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
578 | offset = utmp * fs->data_align; | |
1c90d9f0 | 579 | fs->regs.alloc_regs (reg + 1); |
58894217 JK |
580 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
581 | fs->regs.reg[reg].loc.offset = -offset; | |
582 | break; | |
583 | ||
cfc14b3a | 584 | default: |
b41c5a85 JW |
585 | if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user) |
586 | { | |
587 | /* Handle vendor-specific CFI for different architectures. */ | |
588 | if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs)) | |
589 | error (_("Call Frame Instruction op %d in vendor extension " | |
590 | "space is not handled on this architecture."), | |
591 | insn); | |
592 | } | |
593 | else | |
594 | internal_error (__FILE__, __LINE__, | |
595 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
596 | } |
597 | } | |
598 | } | |
599 | ||
111c6489 JK |
600 | if (fs->initial.reg == NULL) |
601 | { | |
602 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
1c90d9f0 | 603 | delete fs->regs.prev; |
111c6489 JK |
604 | fs->regs.prev = NULL; |
605 | } | |
606 | ||
607 | return insn_ptr; | |
cfc14b3a | 608 | } |
1c90d9f0 YQ |
609 | |
610 | #if GDB_SELF_TEST | |
611 | ||
612 | namespace selftests { | |
613 | ||
614 | /* Unit test to function execute_cfa_program. */ | |
615 | ||
616 | static void | |
617 | execute_cfa_program_test (struct gdbarch *gdbarch) | |
618 | { | |
619 | struct dwarf2_fde fde; | |
620 | struct dwarf2_cie cie; | |
621 | ||
622 | memset (&fde, 0, sizeof fde); | |
623 | memset (&cie, 0, sizeof cie); | |
624 | ||
625 | cie.data_alignment_factor = -4; | |
626 | cie.code_alignment_factor = 2; | |
627 | fde.cie = &cie; | |
628 | ||
629 | dwarf2_frame_state fs (0, fde.cie); | |
630 | ||
631 | gdb_byte insns[] = | |
632 | { | |
633 | DW_CFA_def_cfa, 1, 4, /* DW_CFA_def_cfa: r1 ofs 4 */ | |
634 | DW_CFA_offset | 0x2, 1, /* DW_CFA_offset: r2 at cfa-4 */ | |
635 | DW_CFA_remember_state, | |
636 | DW_CFA_restore_state, | |
637 | }; | |
638 | ||
639 | const gdb_byte *insn_end = insns + sizeof (insns); | |
640 | const gdb_byte *out = execute_cfa_program (&fde, insns, insn_end, gdbarch, | |
641 | 0, &fs); | |
642 | ||
643 | SELF_CHECK (out == insn_end); | |
644 | SELF_CHECK (fs.pc == 0); | |
645 | ||
646 | /* The instructions above only use r1 and r2, but the register numbers | |
647 | used are adjusted by dwarf2_frame_adjust_regnum. */ | |
648 | auto r1 = dwarf2_frame_adjust_regnum (gdbarch, 1, fde.eh_frame_p); | |
649 | auto r2 = dwarf2_frame_adjust_regnum (gdbarch, 2, fde.eh_frame_p); | |
650 | ||
651 | SELF_CHECK (fs.regs.num_regs == (std::max (r1, r2) + 1)); | |
652 | ||
653 | SELF_CHECK (fs.regs.reg[r2].how == DWARF2_FRAME_REG_SAVED_OFFSET); | |
654 | SELF_CHECK (fs.regs.reg[r2].loc.offset == -4); | |
655 | ||
656 | for (auto i = 0; i < fs.regs.num_regs; i++) | |
657 | if (i != r2) | |
658 | SELF_CHECK (fs.regs.reg[i].how == DWARF2_FRAME_REG_UNSPECIFIED); | |
659 | ||
660 | SELF_CHECK (fs.regs.cfa_reg == 1); | |
661 | SELF_CHECK (fs.regs.cfa_offset == 4); | |
662 | SELF_CHECK (fs.regs.cfa_how == CFA_REG_OFFSET); | |
663 | SELF_CHECK (fs.regs.cfa_exp == NULL); | |
664 | SELF_CHECK (fs.regs.prev == NULL); | |
665 | } | |
666 | ||
667 | } // namespace selftests | |
668 | #endif /* GDB_SELF_TEST */ | |
669 | ||
8f22cb90 | 670 | \f |
cfc14b3a | 671 | |
8f22cb90 | 672 | /* Architecture-specific operations. */ |
cfc14b3a | 673 | |
8f22cb90 MK |
674 | /* Per-architecture data key. */ |
675 | static struct gdbarch_data *dwarf2_frame_data; | |
676 | ||
677 | struct dwarf2_frame_ops | |
678 | { | |
679 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
680 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
681 | struct frame_info *); | |
3ed09a32 | 682 | |
4a4e5149 | 683 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 684 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 685 | |
4fc771b8 DJ |
686 | /* Convert .eh_frame register number to DWARF register number, or |
687 | adjust .debug_frame register number. */ | |
688 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
689 | }; |
690 | ||
8f22cb90 MK |
691 | /* Default architecture-specific register state initialization |
692 | function. */ | |
693 | ||
694 | static void | |
695 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 696 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 697 | struct frame_info *this_frame) |
8f22cb90 MK |
698 | { |
699 | /* If we have a register that acts as a program counter, mark it as | |
700 | a destination for the return address. If we have a register that | |
701 | serves as the stack pointer, arrange for it to be filled with the | |
702 | call frame address (CFA). The other registers are marked as | |
703 | unspecified. | |
704 | ||
705 | We copy the return address to the program counter, since many | |
706 | parts in GDB assume that it is possible to get the return address | |
707 | by unwinding the program counter register. However, on ISA's | |
708 | with a dedicated return address register, the CFI usually only | |
709 | contains information to unwind that return address register. | |
710 | ||
711 | The reason we're treating the stack pointer special here is | |
712 | because in many cases GCC doesn't emit CFI for the stack pointer | |
713 | and implicitly assumes that it is equal to the CFA. This makes | |
714 | some sense since the DWARF specification (version 3, draft 8, | |
715 | p. 102) says that: | |
716 | ||
717 | "Typically, the CFA is defined to be the value of the stack | |
718 | pointer at the call site in the previous frame (which may be | |
719 | different from its value on entry to the current frame)." | |
720 | ||
721 | However, this isn't true for all platforms supported by GCC | |
722 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
723 | their own architecture-specific initialization function. */ | |
05cbe71a | 724 | |
ad010def | 725 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 726 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 727 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
728 | reg->how = DWARF2_FRAME_REG_CFA; |
729 | } | |
05cbe71a | 730 | |
8f22cb90 | 731 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 732 | |
8f22cb90 | 733 | static void * |
030f20e1 | 734 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
735 | { |
736 | struct dwarf2_frame_ops *ops; | |
737 | ||
030f20e1 | 738 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
739 | ops->init_reg = dwarf2_frame_default_init_reg; |
740 | return ops; | |
741 | } | |
05cbe71a | 742 | |
8f22cb90 MK |
743 | /* Set the architecture-specific register state initialization |
744 | function for GDBARCH to INIT_REG. */ | |
745 | ||
746 | void | |
747 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
748 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
749 | struct dwarf2_frame_state_reg *, |
750 | struct frame_info *)) | |
8f22cb90 | 751 | { |
9a3c8263 SM |
752 | struct dwarf2_frame_ops *ops |
753 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 754 | |
8f22cb90 MK |
755 | ops->init_reg = init_reg; |
756 | } | |
757 | ||
758 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
759 | |
760 | static void | |
761 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 762 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 763 | struct frame_info *this_frame) |
05cbe71a | 764 | { |
9a3c8263 SM |
765 | struct dwarf2_frame_ops *ops |
766 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 767 | |
4a4e5149 | 768 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 769 | } |
3ed09a32 DJ |
770 | |
771 | /* Set the architecture-specific signal trampoline recognition | |
772 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
773 | ||
774 | void | |
775 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
776 | int (*signal_frame_p) (struct gdbarch *, | |
777 | struct frame_info *)) | |
778 | { | |
9a3c8263 SM |
779 | struct dwarf2_frame_ops *ops |
780 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
781 | |
782 | ops->signal_frame_p = signal_frame_p; | |
783 | } | |
784 | ||
785 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 786 | THIS_FRAME. */ |
3ed09a32 DJ |
787 | |
788 | static int | |
789 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 790 | struct frame_info *this_frame) |
3ed09a32 | 791 | { |
9a3c8263 SM |
792 | struct dwarf2_frame_ops *ops |
793 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
794 | |
795 | if (ops->signal_frame_p == NULL) | |
796 | return 0; | |
4a4e5149 | 797 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 798 | } |
4bf8967c | 799 | |
4fc771b8 DJ |
800 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
801 | register numbers. */ | |
4bf8967c AS |
802 | |
803 | void | |
4fc771b8 DJ |
804 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
805 | int (*adjust_regnum) (struct gdbarch *, | |
806 | int, int)) | |
4bf8967c | 807 | { |
9a3c8263 SM |
808 | struct dwarf2_frame_ops *ops |
809 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 810 | |
4fc771b8 | 811 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
812 | } |
813 | ||
4fc771b8 DJ |
814 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
815 | register. */ | |
4bf8967c | 816 | |
4fc771b8 | 817 | static int |
3e43a32a MS |
818 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
819 | int regnum, int eh_frame_p) | |
4bf8967c | 820 | { |
9a3c8263 SM |
821 | struct dwarf2_frame_ops *ops |
822 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 823 | |
4fc771b8 | 824 | if (ops->adjust_regnum == NULL) |
4bf8967c | 825 | return regnum; |
4fc771b8 | 826 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 827 | } |
303b6f5d DJ |
828 | |
829 | static void | |
830 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
831 | struct dwarf2_fde *fde) | |
832 | { | |
43f3e411 | 833 | struct compunit_symtab *cust; |
303b6f5d | 834 | |
43f3e411 DE |
835 | cust = find_pc_compunit_symtab (fs->pc); |
836 | if (cust == NULL) | |
303b6f5d DJ |
837 | return; |
838 | ||
43f3e411 | 839 | if (producer_is_realview (COMPUNIT_PRODUCER (cust))) |
a6c727b2 DJ |
840 | { |
841 | if (fde->cie->version == 1) | |
842 | fs->armcc_cfa_offsets_sf = 1; | |
843 | ||
844 | if (fde->cie->version == 1) | |
845 | fs->armcc_cfa_offsets_reversed = 1; | |
846 | ||
847 | /* The reversed offset problem is present in some compilers | |
848 | using DWARF3, but it was eventually fixed. Check the ARM | |
849 | defined augmentations, which are in the format "armcc" followed | |
850 | by a list of one-character options. The "+" option means | |
851 | this problem is fixed (no quirk needed). If the armcc | |
852 | augmentation is missing, the quirk is needed. */ | |
853 | if (fde->cie->version == 3 | |
61012eef | 854 | && (!startswith (fde->cie->augmentation, "armcc") |
a6c727b2 DJ |
855 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) |
856 | fs->armcc_cfa_offsets_reversed = 1; | |
857 | ||
858 | return; | |
859 | } | |
303b6f5d | 860 | } |
8f22cb90 MK |
861 | \f |
862 | ||
a8fd5589 TT |
863 | /* See dwarf2-frame.h. */ |
864 | ||
865 | int | |
866 | dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc, | |
867 | struct dwarf2_per_cu_data *data, | |
868 | int *regnum_out, LONGEST *offset_out, | |
869 | CORE_ADDR *text_offset_out, | |
870 | const gdb_byte **cfa_start_out, | |
871 | const gdb_byte **cfa_end_out) | |
9f6f94ff | 872 | { |
9f6f94ff | 873 | struct dwarf2_fde *fde; |
22e048c9 | 874 | CORE_ADDR text_offset; |
afe37d6b | 875 | CORE_ADDR pc1 = pc; |
9f6f94ff TT |
876 | |
877 | /* Find the correct FDE. */ | |
afe37d6b | 878 | fde = dwarf2_frame_find_fde (&pc1, &text_offset); |
9f6f94ff TT |
879 | if (fde == NULL) |
880 | error (_("Could not compute CFA; needed to translate this expression")); | |
881 | ||
afe37d6b | 882 | dwarf2_frame_state fs (pc1, fde->cie); |
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; | |
9f6f94ff TT |
893 | |
894 | /* Then decode the insns in the FDE up to our target PC. */ | |
895 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs); | |
896 | ||
897 | /* Calculate the CFA. */ | |
898 | switch (fs.regs.cfa_how) | |
899 | { | |
900 | case CFA_REG_OFFSET: | |
901 | { | |
0fde2c53 | 902 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg); |
a8fd5589 TT |
903 | |
904 | *regnum_out = regnum; | |
905 | if (fs.armcc_cfa_offsets_reversed) | |
906 | *offset_out = -fs.regs.cfa_offset; | |
907 | else | |
908 | *offset_out = fs.regs.cfa_offset; | |
909 | return 1; | |
9f6f94ff | 910 | } |
9f6f94ff TT |
911 | |
912 | case CFA_EXP: | |
a8fd5589 TT |
913 | *text_offset_out = text_offset; |
914 | *cfa_start_out = fs.regs.cfa_exp; | |
915 | *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len; | |
916 | return 0; | |
9f6f94ff TT |
917 | |
918 | default: | |
919 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
920 | } | |
921 | } | |
922 | ||
923 | \f | |
8f22cb90 MK |
924 | struct dwarf2_frame_cache |
925 | { | |
926 | /* DWARF Call Frame Address. */ | |
927 | CORE_ADDR cfa; | |
928 | ||
8fbca658 PA |
929 | /* Set if the return address column was marked as unavailable |
930 | (required non-collected memory or registers to compute). */ | |
931 | int unavailable_retaddr; | |
932 | ||
0228dfb9 DJ |
933 | /* Set if the return address column was marked as undefined. */ |
934 | int undefined_retaddr; | |
935 | ||
8f22cb90 MK |
936 | /* Saved registers, indexed by GDB register number, not by DWARF |
937 | register number. */ | |
938 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
939 | |
940 | /* Return address register. */ | |
941 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
942 | |
943 | /* Target address size in bytes. */ | |
944 | int addr_size; | |
ac56253d TT |
945 | |
946 | /* The .text offset. */ | |
947 | CORE_ADDR text_offset; | |
111c6489 | 948 | |
1ec56e88 PA |
949 | /* True if we already checked whether this frame is the bottom frame |
950 | of a virtual tail call frame chain. */ | |
951 | int checked_tailcall_bottom; | |
952 | ||
111c6489 JK |
953 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME |
954 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
955 | involved. Non-bottom frames of a virtual tail call frames chain use | |
956 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
957 | them. */ | |
958 | void *tailcall_cache; | |
1ec56e88 PA |
959 | |
960 | /* The number of bytes to subtract from TAILCALL_FRAME frames frame | |
961 | base to get the SP, to simulate the return address pushed on the | |
962 | stack. */ | |
963 | LONGEST entry_cfa_sp_offset; | |
964 | int entry_cfa_sp_offset_p; | |
8f22cb90 | 965 | }; |
05cbe71a | 966 | |
b9362cc7 | 967 | static struct dwarf2_frame_cache * |
4a4e5149 | 968 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 969 | { |
4a4e5149 | 970 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
ad010def UW |
971 | const int num_regs = gdbarch_num_regs (gdbarch) |
972 | + gdbarch_num_pseudo_regs (gdbarch); | |
cfc14b3a | 973 | struct dwarf2_frame_cache *cache; |
cfc14b3a | 974 | struct dwarf2_fde *fde; |
111c6489 | 975 | CORE_ADDR entry_pc; |
111c6489 | 976 | const gdb_byte *instr; |
cfc14b3a MK |
977 | |
978 | if (*this_cache) | |
9a3c8263 | 979 | return (struct dwarf2_frame_cache *) *this_cache; |
cfc14b3a MK |
980 | |
981 | /* Allocate a new cache. */ | |
982 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
983 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 984 | *this_cache = cache; |
cfc14b3a | 985 | |
cfc14b3a MK |
986 | /* Unwind the PC. |
987 | ||
4a4e5149 | 988 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 989 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 990 | its return address. As a result the return address will |
cfc14b3a | 991 | point at some random instruction, and the CFI for that |
e4e9607c | 992 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
993 | this problem by substracting 1 from the return address to get an |
994 | address in the middle of a presumed call instruction (or the | |
995 | instruction in the associated delay slot). This should only be | |
996 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 997 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 998 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
999 | reliable the method is though; there is the potential for the |
1000 | register state pre-call being different to that on return. */ | |
afe37d6b | 1001 | CORE_ADDR pc1 = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1002 | |
1003 | /* Find the correct FDE. */ | |
afe37d6b | 1004 | fde = dwarf2_frame_find_fde (&pc1, &cache->text_offset); |
cfc14b3a MK |
1005 | gdb_assert (fde != NULL); |
1006 | ||
afe37d6b YQ |
1007 | /* Allocate and initialize the frame state. */ |
1008 | struct dwarf2_frame_state fs (pc1, fde->cie); | |
1009 | ||
ae0d2f24 | 1010 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1011 | |
303b6f5d | 1012 | /* Check for "quirks" - known bugs in producers. */ |
afe37d6b | 1013 | dwarf2_frame_find_quirks (&fs, fde); |
303b6f5d | 1014 | |
cfc14b3a | 1015 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1016 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 | 1017 | fde->cie->end, gdbarch, |
afe37d6b | 1018 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a MK |
1019 | |
1020 | /* Save the initialized register set. */ | |
afe37d6b | 1021 | fs.initial = fs.regs; |
cfc14b3a | 1022 | |
111c6489 JK |
1023 | if (get_frame_func_if_available (this_frame, &entry_pc)) |
1024 | { | |
1025 | /* Decode the insns in the FDE up to the entry PC. */ | |
1026 | instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, | |
afe37d6b | 1027 | entry_pc, &fs); |
111c6489 | 1028 | |
afe37d6b YQ |
1029 | if (fs.regs.cfa_how == CFA_REG_OFFSET |
1030 | && (dwarf_reg_to_regnum (gdbarch, fs.regs.cfa_reg) | |
111c6489 JK |
1031 | == gdbarch_sp_regnum (gdbarch))) |
1032 | { | |
afe37d6b | 1033 | cache->entry_cfa_sp_offset = fs.regs.cfa_offset; |
1ec56e88 | 1034 | cache->entry_cfa_sp_offset_p = 1; |
111c6489 JK |
1035 | } |
1036 | } | |
1037 | else | |
1038 | instr = fde->instructions; | |
1039 | ||
cfc14b3a | 1040 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1041 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
afe37d6b | 1042 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a | 1043 | |
492d29ea | 1044 | TRY |
cfc14b3a | 1045 | { |
8fbca658 | 1046 | /* Calculate the CFA. */ |
afe37d6b | 1047 | switch (fs.regs.cfa_how) |
8fbca658 PA |
1048 | { |
1049 | case CFA_REG_OFFSET: | |
afe37d6b YQ |
1050 | cache->cfa = read_addr_from_reg (this_frame, fs.regs.cfa_reg); |
1051 | if (fs.armcc_cfa_offsets_reversed) | |
1052 | cache->cfa -= fs.regs.cfa_offset; | |
8fbca658 | 1053 | else |
afe37d6b | 1054 | cache->cfa += fs.regs.cfa_offset; |
8fbca658 PA |
1055 | break; |
1056 | ||
1057 | case CFA_EXP: | |
1058 | cache->cfa = | |
afe37d6b | 1059 | execute_stack_op (fs.regs.cfa_exp, fs.regs.cfa_exp_len, |
8fbca658 PA |
1060 | cache->addr_size, cache->text_offset, |
1061 | this_frame, 0, 0); | |
1062 | break; | |
1063 | ||
1064 | default: | |
1065 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1066 | } | |
1067 | } | |
492d29ea | 1068 | CATCH (ex, RETURN_MASK_ERROR) |
8fbca658 PA |
1069 | { |
1070 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1071 | { | |
1072 | cache->unavailable_retaddr = 1; | |
1073 | return cache; | |
1074 | } | |
cfc14b3a | 1075 | |
8fbca658 | 1076 | throw_exception (ex); |
cfc14b3a | 1077 | } |
492d29ea | 1078 | END_CATCH |
cfc14b3a | 1079 | |
05cbe71a | 1080 | /* Initialize the register state. */ |
3e2c4033 AC |
1081 | { |
1082 | int regnum; | |
e4e9607c | 1083 | |
3e2c4033 | 1084 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1085 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1086 | } |
1087 | ||
1088 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1089 | location information in the cache. Note that we don't skip the |
1090 | return address column; it's perfectly all right for it to | |
0fde2c53 | 1091 | correspond to a real register. */ |
3e2c4033 AC |
1092 | { |
1093 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1094 | |
afe37d6b | 1095 | for (column = 0; column < fs.regs.num_regs; column++) |
3e2c4033 | 1096 | { |
3e2c4033 | 1097 | /* Use the GDB register number as the destination index. */ |
0fde2c53 | 1098 | int regnum = dwarf_reg_to_regnum (gdbarch, column); |
3e2c4033 | 1099 | |
0fde2c53 | 1100 | /* Protect against a target returning a bad register. */ |
3e2c4033 AC |
1101 | if (regnum < 0 || regnum >= num_regs) |
1102 | continue; | |
1103 | ||
1104 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1105 | of all debug info registers. If it doesn't, complain (but |
1106 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1107 | unspecified register implies "same value" when CFI (draft |
1108 | 7) specifies nothing at all. Such a register could equally | |
1109 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1110 | isn't sufficient; it only checks that all registers in the |
1111 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1112 | problems when a debug info register falls outside of the |
e4e9607c | 1113 | table. We need a way of iterating through all the valid |
3e2c4033 | 1114 | DWARF2 register numbers. */ |
afe37d6b | 1115 | if (fs.regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1116 | { |
1117 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
b98664d3 | 1118 | complaint (_("\ |
5af949e3 | 1119 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1120 | gdbarch_register_name (gdbarch, regnum), |
afe37d6b | 1121 | paddress (gdbarch, fs.pc)); |
f059bf6f | 1122 | } |
35889917 | 1123 | else |
afe37d6b | 1124 | cache->reg[regnum] = fs.regs.reg[column]; |
3e2c4033 AC |
1125 | } |
1126 | } | |
cfc14b3a | 1127 | |
8d5a9abc MK |
1128 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1129 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1130 | { |
1131 | int regnum; | |
1132 | ||
1133 | for (regnum = 0; regnum < num_regs; regnum++) | |
1134 | { | |
8d5a9abc MK |
1135 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1136 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1137 | { |
05cbe71a | 1138 | struct dwarf2_frame_state_reg *retaddr_reg = |
afe37d6b | 1139 | &fs.regs.reg[fs.retaddr_column]; |
05cbe71a | 1140 | |
d4f10bf2 MK |
1141 | /* It seems rather bizarre to specify an "empty" column as |
1142 | the return adress column. However, this is exactly | |
1143 | what GCC does on some targets. It turns out that GCC | |
1144 | assumes that the return address can be found in the | |
1145 | register corresponding to the return address column. | |
8d5a9abc MK |
1146 | Incidentally, that's how we should treat a return |
1147 | address column specifying "same value" too. */ | |
afe37d6b | 1148 | if (fs.retaddr_column < fs.regs.num_regs |
05cbe71a MK |
1149 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
1150 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1151 | { |
1152 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
1153 | cache->reg[regnum] = *retaddr_reg; | |
1154 | else | |
1155 | cache->retaddr_reg = *retaddr_reg; | |
1156 | } | |
35889917 MK |
1157 | else |
1158 | { | |
8d5a9abc MK |
1159 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1160 | { | |
afe37d6b | 1161 | cache->reg[regnum].loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1162 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; |
1163 | } | |
1164 | else | |
1165 | { | |
afe37d6b | 1166 | cache->retaddr_reg.loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1167 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; |
1168 | } | |
35889917 MK |
1169 | } |
1170 | } | |
1171 | } | |
1172 | } | |
cfc14b3a | 1173 | |
afe37d6b YQ |
1174 | if (fs.retaddr_column < fs.regs.num_regs |
1175 | && fs.regs.reg[fs.retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
0228dfb9 DJ |
1176 | cache->undefined_retaddr = 1; |
1177 | ||
cfc14b3a MK |
1178 | return cache; |
1179 | } | |
1180 | ||
8fbca658 PA |
1181 | static enum unwind_stop_reason |
1182 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1183 | void **this_cache) | |
1184 | { | |
1185 | struct dwarf2_frame_cache *cache | |
1186 | = dwarf2_frame_cache (this_frame, this_cache); | |
1187 | ||
1188 | if (cache->unavailable_retaddr) | |
1189 | return UNWIND_UNAVAILABLE; | |
1190 | ||
1191 | if (cache->undefined_retaddr) | |
1192 | return UNWIND_OUTERMOST; | |
1193 | ||
1194 | return UNWIND_NO_REASON; | |
1195 | } | |
1196 | ||
cfc14b3a | 1197 | static void |
4a4e5149 | 1198 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1199 | struct frame_id *this_id) |
1200 | { | |
1201 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1202 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1203 | |
8fbca658 | 1204 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1205 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1206 | else if (cache->undefined_retaddr) | |
8fbca658 | 1207 | return; |
5ce0145d PA |
1208 | else |
1209 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1210 | } |
1211 | ||
4a4e5149 DJ |
1212 | static struct value * |
1213 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1214 | int regnum) | |
93d42b30 | 1215 | { |
4a4e5149 | 1216 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1217 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1218 | dwarf2_frame_cache (this_frame, this_cache); |
1219 | CORE_ADDR addr; | |
1220 | int realnum; | |
cfc14b3a | 1221 | |
1ec56e88 PA |
1222 | /* Check whether THIS_FRAME is the bottom frame of a virtual tail |
1223 | call frame chain. */ | |
1224 | if (!cache->checked_tailcall_bottom) | |
1225 | { | |
1226 | cache->checked_tailcall_bottom = 1; | |
1227 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, | |
1228 | (cache->entry_cfa_sp_offset_p | |
1229 | ? &cache->entry_cfa_sp_offset : NULL)); | |
1230 | } | |
1231 | ||
111c6489 JK |
1232 | /* Non-bottom frames of a virtual tail call frames chain use |
1233 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1234 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1235 | unwind the register, tail call frames are assumed to have the register set | |
1236 | of the top caller. */ | |
1237 | if (cache->tailcall_cache) | |
1238 | { | |
1239 | struct value *val; | |
1240 | ||
1241 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1242 | &cache->tailcall_cache, | |
1243 | regnum); | |
1244 | if (val) | |
1245 | return val; | |
1246 | } | |
1247 | ||
cfc14b3a MK |
1248 | switch (cache->reg[regnum].how) |
1249 | { | |
05cbe71a | 1250 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1251 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1252 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1253 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1254 | |
05cbe71a | 1255 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1256 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1257 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1258 | |
05cbe71a | 1259 | case DWARF2_FRAME_REG_SAVED_REG: |
0fde2c53 DE |
1260 | realnum = dwarf_reg_to_regnum_or_error |
1261 | (gdbarch, cache->reg[regnum].loc.reg); | |
4a4e5149 | 1262 | return frame_unwind_got_register (this_frame, regnum, realnum); |
cfc14b3a | 1263 | |
05cbe71a | 1264 | case DWARF2_FRAME_REG_SAVED_EXP: |
b348037f YQ |
1265 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1266 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1267 | cache->addr_size, cache->text_offset, |
1268 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1269 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1270 | |
46ea248b | 1271 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1272 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1273 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1274 | |
1275 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
b348037f YQ |
1276 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1277 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1278 | cache->addr_size, cache->text_offset, |
1279 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1280 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1281 | |
05cbe71a | 1282 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1283 | /* GCC, in its infinite wisdom decided to not provide unwind |
1284 | information for registers that are "same value". Since | |
1285 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1286 | registers are actually undefined (which is different to CFI | |
1287 | "undefined"). Code above issues a complaint about this. | |
1288 | Here just fudge the books, assume GCC, and that the value is | |
1289 | more inner on the stack. */ | |
4a4e5149 | 1290 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1291 | |
05cbe71a | 1292 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1293 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1294 | |
05cbe71a | 1295 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1296 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1297 | |
ea7963f0 | 1298 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1299 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1300 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1301 | |
8d5a9abc | 1302 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 | 1303 | addr = cache->reg[regnum].loc.offset; |
0fde2c53 | 1304 | regnum = dwarf_reg_to_regnum_or_error |
4a4e5149 DJ |
1305 | (gdbarch, cache->retaddr_reg.loc.reg); |
1306 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1307 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1308 | |
b39cc962 DJ |
1309 | case DWARF2_FRAME_REG_FN: |
1310 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1311 | ||
cfc14b3a | 1312 | default: |
e2e0b3e5 | 1313 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1314 | } |
1315 | } | |
1316 | ||
111c6489 JK |
1317 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1318 | call frames chain. */ | |
1319 | ||
1320 | static void | |
1321 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1322 | { | |
1323 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1324 | ||
1325 | if (cache->tailcall_cache) | |
1326 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1327 | } | |
1328 | ||
4a4e5149 DJ |
1329 | static int |
1330 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1331 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1332 | { |
3c3bb058 AB |
1333 | if (!dwarf2_frame_unwinders_enabled_p) |
1334 | return 0; | |
1335 | ||
1ce5d6dd | 1336 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1337 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1338 | end up returning something past the end of this function's body. |
1339 | If the frame we're sniffing for is a signal frame whose start | |
1340 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1341 | extend one byte before its start address or we could potentially |
1342 | select the FDE of the previous function. */ | |
1343 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1344 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1345 | |
56c987f6 | 1346 | if (!fde) |
4a4e5149 | 1347 | return 0; |
3ed09a32 DJ |
1348 | |
1349 | /* On some targets, signal trampolines may have unwind information. | |
1350 | We need to recognize them so that we set the frame type | |
1351 | correctly. */ | |
1352 | ||
56c987f6 | 1353 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1354 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1355 | this_frame)) | |
1356 | return self->type == SIGTRAMP_FRAME; | |
1357 | ||
111c6489 JK |
1358 | if (self->type != NORMAL_FRAME) |
1359 | return 0; | |
1360 | ||
111c6489 | 1361 | return 1; |
4a4e5149 DJ |
1362 | } |
1363 | ||
1364 | static const struct frame_unwind dwarf2_frame_unwind = | |
1365 | { | |
1366 | NORMAL_FRAME, | |
8fbca658 | 1367 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1368 | dwarf2_frame_this_id, |
1369 | dwarf2_frame_prev_register, | |
1370 | NULL, | |
111c6489 JK |
1371 | dwarf2_frame_sniffer, |
1372 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1373 | }; |
1374 | ||
1375 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1376 | { | |
1377 | SIGTRAMP_FRAME, | |
8fbca658 | 1378 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1379 | dwarf2_frame_this_id, |
1380 | dwarf2_frame_prev_register, | |
1381 | NULL, | |
111c6489 JK |
1382 | dwarf2_frame_sniffer, |
1383 | ||
1384 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1385 | NULL | |
4a4e5149 | 1386 | }; |
cfc14b3a | 1387 | |
4a4e5149 DJ |
1388 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1389 | ||
1390 | void | |
1391 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1392 | { | |
111c6489 JK |
1393 | /* TAILCALL_FRAME must be first to find the record by |
1394 | dwarf2_tailcall_sniffer_first. */ | |
1395 | frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind); | |
1396 | ||
4a4e5149 DJ |
1397 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); |
1398 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1399 | } |
1400 | \f | |
1401 | ||
1402 | /* There is no explicitly defined relationship between the CFA and the | |
1403 | location of frame's local variables and arguments/parameters. | |
1404 | Therefore, frame base methods on this page should probably only be | |
1405 | used as a last resort, just to avoid printing total garbage as a | |
1406 | response to the "info frame" command. */ | |
1407 | ||
1408 | static CORE_ADDR | |
4a4e5149 | 1409 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1410 | { |
1411 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1412 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1413 | |
1414 | return cache->cfa; | |
1415 | } | |
1416 | ||
1417 | static const struct frame_base dwarf2_frame_base = | |
1418 | { | |
1419 | &dwarf2_frame_unwind, | |
1420 | dwarf2_frame_base_address, | |
1421 | dwarf2_frame_base_address, | |
1422 | dwarf2_frame_base_address | |
1423 | }; | |
1424 | ||
1425 | const struct frame_base * | |
4a4e5149 | 1426 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1427 | { |
4a4e5149 | 1428 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1429 | |
ac56253d | 1430 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1431 | return &dwarf2_frame_base; |
1432 | ||
1433 | return NULL; | |
1434 | } | |
e7802207 TT |
1435 | |
1436 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1437 | the DWARF unwinder. This is used to implement | |
1438 | DW_OP_call_frame_cfa. */ | |
1439 | ||
1440 | CORE_ADDR | |
1441 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1442 | { | |
0b722aec MM |
1443 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1444 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1445 | throw_error (NOT_AVAILABLE_ERROR, | |
1446 | _("cfa not available for record btrace target")); | |
1447 | ||
e7802207 TT |
1448 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1449 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1450 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1451 | throw_error (NOT_AVAILABLE_ERROR, | |
1452 | _("can't compute CFA for this frame: " | |
1453 | "required registers or memory are unavailable")); | |
14aba1ac JB |
1454 | |
1455 | if (get_frame_id (this_frame).stack_status != FID_STACK_VALID) | |
1456 | throw_error (NOT_AVAILABLE_ERROR, | |
1457 | _("can't compute CFA for this frame: " | |
1458 | "frame base not available")); | |
1459 | ||
e7802207 TT |
1460 | return get_frame_base (this_frame); |
1461 | } | |
cfc14b3a | 1462 | \f |
8f22cb90 | 1463 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1464 | |
cfc14b3a | 1465 | static unsigned int |
f664829e | 1466 | read_1_byte (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1467 | { |
852483bc | 1468 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1469 | } |
1470 | ||
1471 | static unsigned int | |
f664829e | 1472 | read_4_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1473 | { |
852483bc | 1474 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1475 | } |
1476 | ||
1477 | static ULONGEST | |
f664829e | 1478 | read_8_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1479 | { |
852483bc | 1480 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1481 | } |
1482 | ||
1483 | static ULONGEST | |
f664829e DE |
1484 | read_initial_length (bfd *abfd, const gdb_byte *buf, |
1485 | unsigned int *bytes_read_ptr) | |
cfc14b3a MK |
1486 | { |
1487 | LONGEST result; | |
1488 | ||
852483bc | 1489 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1490 | if (result == 0xffffffff) |
1491 | { | |
852483bc | 1492 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1493 | *bytes_read_ptr = 12; |
1494 | } | |
1495 | else | |
1496 | *bytes_read_ptr = 4; | |
1497 | ||
1498 | return result; | |
1499 | } | |
1500 | \f | |
1501 | ||
1502 | /* Pointer encoding helper functions. */ | |
1503 | ||
1504 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1505 | technical reasons, it encodes addresses in its FDE's in a different | |
1506 | way. Several "pointer encodings" are supported. The encoding | |
1507 | that's used for a particular FDE is determined by the 'R' | |
1508 | augmentation in the associated CIE. The argument of this | |
1509 | augmentation is a single byte. | |
1510 | ||
1511 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1512 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1513 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1514 | address should be interpreted (absolute, relative to the current | |
1515 | position in the FDE, ...). Bit 7, indicates that the address | |
1516 | should be dereferenced. */ | |
1517 | ||
852483bc | 1518 | static gdb_byte |
cfc14b3a MK |
1519 | encoding_for_size (unsigned int size) |
1520 | { | |
1521 | switch (size) | |
1522 | { | |
1523 | case 2: | |
1524 | return DW_EH_PE_udata2; | |
1525 | case 4: | |
1526 | return DW_EH_PE_udata4; | |
1527 | case 8: | |
1528 | return DW_EH_PE_udata8; | |
1529 | default: | |
e2e0b3e5 | 1530 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1531 | } |
1532 | } | |
1533 | ||
cfc14b3a | 1534 | static CORE_ADDR |
852483bc | 1535 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1536 | int ptr_len, const gdb_byte *buf, |
1537 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1538 | CORE_ADDR func_base) |
cfc14b3a | 1539 | { |
68f6cf99 | 1540 | ptrdiff_t offset; |
cfc14b3a MK |
1541 | CORE_ADDR base; |
1542 | ||
1543 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1544 | FDE's. */ | |
1545 | if (encoding & DW_EH_PE_indirect) | |
1546 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1547 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1548 | |
68f6cf99 MK |
1549 | *bytes_read_ptr = 0; |
1550 | ||
cfc14b3a MK |
1551 | switch (encoding & 0x70) |
1552 | { | |
1553 | case DW_EH_PE_absptr: | |
1554 | base = 0; | |
1555 | break; | |
1556 | case DW_EH_PE_pcrel: | |
f2fec864 | 1557 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1558 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1559 | break; |
0912c7f2 MK |
1560 | case DW_EH_PE_datarel: |
1561 | base = unit->dbase; | |
1562 | break; | |
0fd85043 CV |
1563 | case DW_EH_PE_textrel: |
1564 | base = unit->tbase; | |
1565 | break; | |
03ac2a74 | 1566 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1567 | base = func_base; |
03ac2a74 | 1568 | break; |
68f6cf99 MK |
1569 | case DW_EH_PE_aligned: |
1570 | base = 0; | |
852483bc | 1571 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1572 | if ((offset % ptr_len) != 0) |
1573 | { | |
1574 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1575 | buf += *bytes_read_ptr; | |
1576 | } | |
1577 | break; | |
cfc14b3a | 1578 | default: |
3e43a32a MS |
1579 | internal_error (__FILE__, __LINE__, |
1580 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1581 | } |
1582 | ||
b04de778 | 1583 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1584 | { |
1585 | encoding |= encoding_for_size (ptr_len); | |
1586 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1587 | encoding |= DW_EH_PE_signed; | |
1588 | } | |
cfc14b3a MK |
1589 | |
1590 | switch (encoding & 0x0f) | |
1591 | { | |
a81b10ae MK |
1592 | case DW_EH_PE_uleb128: |
1593 | { | |
9fccedf7 | 1594 | uint64_t value; |
0d45f56e | 1595 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1596 | |
f664829e | 1597 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1598 | return base + value; |
1599 | } | |
cfc14b3a | 1600 | case DW_EH_PE_udata2: |
68f6cf99 | 1601 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1602 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1603 | case DW_EH_PE_udata4: | |
68f6cf99 | 1604 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1605 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1606 | case DW_EH_PE_udata8: | |
68f6cf99 | 1607 | *bytes_read_ptr += 8; |
cfc14b3a | 1608 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1609 | case DW_EH_PE_sleb128: |
1610 | { | |
9fccedf7 | 1611 | int64_t value; |
0d45f56e | 1612 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1613 | |
f664829e | 1614 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1615 | return base + value; |
1616 | } | |
cfc14b3a | 1617 | case DW_EH_PE_sdata2: |
68f6cf99 | 1618 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1619 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1620 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1621 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1622 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1623 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1624 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1625 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1626 | default: | |
3e43a32a MS |
1627 | internal_error (__FILE__, __LINE__, |
1628 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1629 | } |
1630 | } | |
1631 | \f | |
1632 | ||
b01c8410 PP |
1633 | static int |
1634 | bsearch_cie_cmp (const void *key, const void *element) | |
cfc14b3a | 1635 | { |
b01c8410 PP |
1636 | ULONGEST cie_pointer = *(ULONGEST *) key; |
1637 | struct dwarf2_cie *cie = *(struct dwarf2_cie **) element; | |
cfc14b3a | 1638 | |
b01c8410 PP |
1639 | if (cie_pointer == cie->cie_pointer) |
1640 | return 0; | |
cfc14b3a | 1641 | |
b01c8410 PP |
1642 | return (cie_pointer < cie->cie_pointer) ? -1 : 1; |
1643 | } | |
1644 | ||
1645 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ | |
1646 | static struct dwarf2_cie * | |
1647 | find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer) | |
1648 | { | |
1649 | struct dwarf2_cie **p_cie; | |
cfc14b3a | 1650 | |
65a97ab3 PP |
1651 | /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to |
1652 | bsearch be non-NULL. */ | |
1653 | if (cie_table->entries == NULL) | |
1654 | { | |
1655 | gdb_assert (cie_table->num_entries == 0); | |
1656 | return NULL; | |
1657 | } | |
1658 | ||
9a3c8263 SM |
1659 | p_cie = ((struct dwarf2_cie **) |
1660 | bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries, | |
1661 | sizeof (cie_table->entries[0]), bsearch_cie_cmp)); | |
b01c8410 PP |
1662 | if (p_cie != NULL) |
1663 | return *p_cie; | |
cfc14b3a MK |
1664 | return NULL; |
1665 | } | |
1666 | ||
b01c8410 | 1667 | /* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */ |
cfc14b3a | 1668 | static void |
b01c8410 | 1669 | add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie) |
cfc14b3a | 1670 | { |
b01c8410 PP |
1671 | const int n = cie_table->num_entries; |
1672 | ||
1673 | gdb_assert (n < 1 | |
1674 | || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer); | |
1675 | ||
224c3ddb SM |
1676 | cie_table->entries |
1677 | = XRESIZEVEC (struct dwarf2_cie *, cie_table->entries, n + 1); | |
b01c8410 PP |
1678 | cie_table->entries[n] = cie; |
1679 | cie_table->num_entries = n + 1; | |
1680 | } | |
1681 | ||
1682 | static int | |
1683 | bsearch_fde_cmp (const void *key, const void *element) | |
1684 | { | |
1685 | CORE_ADDR seek_pc = *(CORE_ADDR *) key; | |
1686 | struct dwarf2_fde *fde = *(struct dwarf2_fde **) element; | |
9a619af0 | 1687 | |
b01c8410 PP |
1688 | if (seek_pc < fde->initial_location) |
1689 | return -1; | |
1690 | if (seek_pc < fde->initial_location + fde->address_range) | |
1691 | return 0; | |
1692 | return 1; | |
cfc14b3a MK |
1693 | } |
1694 | ||
1695 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1696 | inital location associated with it into *PC. */ | |
1697 | ||
1698 | static struct dwarf2_fde * | |
ac56253d | 1699 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a MK |
1700 | { |
1701 | struct objfile *objfile; | |
1702 | ||
1703 | ALL_OBJFILES (objfile) | |
1704 | { | |
b01c8410 PP |
1705 | struct dwarf2_fde_table *fde_table; |
1706 | struct dwarf2_fde **p_fde; | |
cfc14b3a | 1707 | CORE_ADDR offset; |
b01c8410 | 1708 | CORE_ADDR seek_pc; |
cfc14b3a | 1709 | |
9a3c8263 SM |
1710 | fde_table = ((struct dwarf2_fde_table *) |
1711 | objfile_data (objfile, dwarf2_frame_objfile_data)); | |
b01c8410 | 1712 | if (fde_table == NULL) |
be391dca TT |
1713 | { |
1714 | dwarf2_build_frame_info (objfile); | |
9a3c8263 SM |
1715 | fde_table = ((struct dwarf2_fde_table *) |
1716 | objfile_data (objfile, dwarf2_frame_objfile_data)); | |
be391dca TT |
1717 | } |
1718 | gdb_assert (fde_table != NULL); | |
1719 | ||
1720 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1721 | continue; |
1722 | ||
1723 | gdb_assert (objfile->section_offsets); | |
1724 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1725 | ||
b01c8410 PP |
1726 | gdb_assert (fde_table->num_entries > 0); |
1727 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1728 | continue; | |
1729 | ||
1730 | seek_pc = *pc - offset; | |
9a3c8263 SM |
1731 | p_fde = ((struct dwarf2_fde **) |
1732 | bsearch (&seek_pc, fde_table->entries, fde_table->num_entries, | |
1733 | sizeof (fde_table->entries[0]), bsearch_fde_cmp)); | |
b01c8410 PP |
1734 | if (p_fde != NULL) |
1735 | { | |
1736 | *pc = (*p_fde)->initial_location + offset; | |
ac56253d TT |
1737 | if (out_offset) |
1738 | *out_offset = offset; | |
b01c8410 PP |
1739 | return *p_fde; |
1740 | } | |
cfc14b3a | 1741 | } |
cfc14b3a MK |
1742 | return NULL; |
1743 | } | |
1744 | ||
b01c8410 | 1745 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1746 | static void |
b01c8410 | 1747 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1748 | { |
b01c8410 PP |
1749 | if (fde->address_range == 0) |
1750 | /* Discard useless FDEs. */ | |
1751 | return; | |
1752 | ||
1753 | fde_table->num_entries += 1; | |
224c3ddb SM |
1754 | fde_table->entries = XRESIZEVEC (struct dwarf2_fde *, fde_table->entries, |
1755 | fde_table->num_entries); | |
b01c8410 | 1756 | fde_table->entries[fde_table->num_entries - 1] = fde; |
cfc14b3a MK |
1757 | } |
1758 | ||
cfc14b3a | 1759 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1760 | |
8bd90839 FM |
1761 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1762 | or any of them. */ | |
1763 | ||
1764 | enum eh_frame_type | |
1765 | { | |
1766 | EH_CIE_TYPE_ID = 1 << 0, | |
1767 | EH_FDE_TYPE_ID = 1 << 1, | |
1768 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1769 | }; | |
1770 | ||
f664829e DE |
1771 | static const gdb_byte *decode_frame_entry (struct comp_unit *unit, |
1772 | const gdb_byte *start, | |
1773 | int eh_frame_p, | |
1774 | struct dwarf2_cie_table *cie_table, | |
1775 | struct dwarf2_fde_table *fde_table, | |
1776 | enum eh_frame_type entry_type); | |
8bd90839 FM |
1777 | |
1778 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1779 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1780 | |
f664829e DE |
1781 | static const gdb_byte * |
1782 | decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, | |
1783 | int eh_frame_p, | |
b01c8410 | 1784 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
1785 | struct dwarf2_fde_table *fde_table, |
1786 | enum eh_frame_type entry_type) | |
cfc14b3a | 1787 | { |
5e2b427d | 1788 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
f664829e | 1789 | const gdb_byte *buf, *end; |
cfc14b3a MK |
1790 | LONGEST length; |
1791 | unsigned int bytes_read; | |
6896c0c7 RH |
1792 | int dwarf64_p; |
1793 | ULONGEST cie_id; | |
cfc14b3a | 1794 | ULONGEST cie_pointer; |
9fccedf7 DE |
1795 | int64_t sleb128; |
1796 | uint64_t uleb128; | |
cfc14b3a | 1797 | |
6896c0c7 | 1798 | buf = start; |
cfc14b3a MK |
1799 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1800 | buf += bytes_read; | |
1801 | end = buf + length; | |
1802 | ||
0963b4bd | 1803 | /* Are we still within the section? */ |
6896c0c7 RH |
1804 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) |
1805 | return NULL; | |
1806 | ||
cfc14b3a MK |
1807 | if (length == 0) |
1808 | return end; | |
1809 | ||
6896c0c7 RH |
1810 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1811 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1812 | |
6896c0c7 | 1813 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1814 | if (eh_frame_p) |
1815 | cie_id = 0; | |
1816 | else if (dwarf64_p) | |
1817 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1818 | else |
1819 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1820 | |
1821 | if (dwarf64_p) | |
1822 | { | |
1823 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1824 | buf += 8; | |
1825 | } | |
1826 | else | |
1827 | { | |
1828 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1829 | buf += 4; | |
1830 | } | |
1831 | ||
1832 | if (cie_pointer == cie_id) | |
1833 | { | |
1834 | /* This is a CIE. */ | |
1835 | struct dwarf2_cie *cie; | |
1836 | char *augmentation; | |
28ba0b33 | 1837 | unsigned int cie_version; |
cfc14b3a | 1838 | |
8bd90839 FM |
1839 | /* Check that a CIE was expected. */ |
1840 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1841 | error (_("Found a CIE when not expecting it.")); | |
1842 | ||
cfc14b3a MK |
1843 | /* Record the offset into the .debug_frame section of this CIE. */ |
1844 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1845 | ||
1846 | /* Check whether we've already read it. */ | |
b01c8410 | 1847 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1848 | return end; |
1849 | ||
8d749320 | 1850 | cie = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_cie); |
cfc14b3a MK |
1851 | cie->initial_instructions = NULL; |
1852 | cie->cie_pointer = cie_pointer; | |
1853 | ||
1854 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1855 | depends on the target address size. */ |
1856 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1857 | |
56c987f6 AO |
1858 | /* We'll determine the final value later, but we need to |
1859 | initialize it conservatively. */ | |
1860 | cie->signal_frame = 0; | |
1861 | ||
cfc14b3a | 1862 | /* Check version number. */ |
28ba0b33 | 1863 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1864 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1865 | return NULL; |
303b6f5d | 1866 | cie->version = cie_version; |
cfc14b3a MK |
1867 | buf += 1; |
1868 | ||
1869 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1870 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1871 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1872 | |
303b6f5d DJ |
1873 | /* Ignore armcc augmentations. We only use them for quirks, |
1874 | and that doesn't happen until later. */ | |
61012eef | 1875 | if (startswith (augmentation, "armcc")) |
303b6f5d DJ |
1876 | augmentation += strlen (augmentation); |
1877 | ||
cfc14b3a MK |
1878 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1879 | following the augmentation string, so it must be handled | |
1880 | first. */ | |
1881 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1882 | { | |
1883 | /* Skip. */ | |
5e2b427d | 1884 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1885 | augmentation += 2; |
1886 | } | |
1887 | ||
2dc7f7b3 TT |
1888 | if (cie->version >= 4) |
1889 | { | |
1890 | /* FIXME: check that this is the same as from the CU header. */ | |
1891 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1892 | ++buf; | |
1893 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1894 | ++buf; | |
1895 | } | |
1896 | else | |
1897 | { | |
8da614df | 1898 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1899 | cie->segment_size = 0; |
1900 | } | |
8da614df CV |
1901 | /* Address values in .eh_frame sections are defined to have the |
1902 | target's pointer size. Watchout: This breaks frame info for | |
1903 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1904 | section exists as well. */ |
8da614df CV |
1905 | if (eh_frame_p) |
1906 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1907 | else | |
1908 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1909 | |
f664829e DE |
1910 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1911 | if (buf == NULL) | |
1912 | return NULL; | |
1913 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1914 | |
f664829e DE |
1915 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1916 | if (buf == NULL) | |
1917 | return NULL; | |
1918 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1919 | |
28ba0b33 PB |
1920 | if (cie_version == 1) |
1921 | { | |
1922 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1923 | ++buf; |
28ba0b33 PB |
1924 | } |
1925 | else | |
f664829e DE |
1926 | { |
1927 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1928 | if (buf == NULL) | |
1929 | return NULL; | |
1930 | cie->return_address_register = uleb128; | |
1931 | } | |
1932 | ||
4fc771b8 | 1933 | cie->return_address_register |
5e2b427d | 1934 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1935 | cie->return_address_register, |
1936 | eh_frame_p); | |
4bf8967c | 1937 | |
7131cb6e RH |
1938 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1939 | if (cie->saw_z_augmentation) | |
cfc14b3a | 1940 | { |
9fccedf7 | 1941 | uint64_t length; |
cfc14b3a | 1942 | |
f664829e DE |
1943 | buf = gdb_read_uleb128 (buf, end, &length); |
1944 | if (buf == NULL) | |
6896c0c7 | 1945 | return NULL; |
cfc14b3a MK |
1946 | cie->initial_instructions = buf + length; |
1947 | augmentation++; | |
1948 | } | |
1949 | ||
1950 | while (*augmentation) | |
1951 | { | |
1952 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1953 | if (*augmentation == 'L') | |
1954 | { | |
1955 | /* Skip. */ | |
1956 | buf++; | |
1957 | augmentation++; | |
1958 | } | |
1959 | ||
1960 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1961 | else if (*augmentation == 'R') | |
1962 | { | |
1963 | cie->encoding = *buf++; | |
1964 | augmentation++; | |
1965 | } | |
1966 | ||
1967 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1968 | else if (*augmentation == 'P') | |
1969 | { | |
1234d960 | 1970 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1971 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1972 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1973 | buf, &bytes_read, 0); |
f724bf08 | 1974 | buf += bytes_read; |
cfc14b3a MK |
1975 | augmentation++; |
1976 | } | |
1977 | ||
56c987f6 AO |
1978 | /* "S" indicates a signal frame, such that the return |
1979 | address must not be decremented to locate the call frame | |
1980 | info for the previous frame; it might even be the first | |
1981 | instruction of a function, so decrementing it would take | |
1982 | us to a different function. */ | |
1983 | else if (*augmentation == 'S') | |
1984 | { | |
1985 | cie->signal_frame = 1; | |
1986 | augmentation++; | |
1987 | } | |
1988 | ||
3e9a2e52 DJ |
1989 | /* Otherwise we have an unknown augmentation. Assume that either |
1990 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1991 | else |
1992 | { | |
3e9a2e52 DJ |
1993 | if (cie->initial_instructions) |
1994 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1995 | break; |
1996 | } | |
1997 | } | |
1998 | ||
1999 | cie->initial_instructions = buf; | |
2000 | cie->end = end; | |
b01c8410 | 2001 | cie->unit = unit; |
cfc14b3a | 2002 | |
b01c8410 | 2003 | add_cie (cie_table, cie); |
cfc14b3a MK |
2004 | } |
2005 | else | |
2006 | { | |
2007 | /* This is a FDE. */ | |
2008 | struct dwarf2_fde *fde; | |
3e29f34a | 2009 | CORE_ADDR addr; |
cfc14b3a | 2010 | |
8bd90839 FM |
2011 | /* Check that an FDE was expected. */ |
2012 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
2013 | error (_("Found an FDE when not expecting it.")); | |
2014 | ||
6896c0c7 RH |
2015 | /* In an .eh_frame section, the CIE pointer is the delta between the |
2016 | address within the FDE where the CIE pointer is stored and the | |
2017 | address of the CIE. Convert it to an offset into the .eh_frame | |
2018 | section. */ | |
cfc14b3a MK |
2019 | if (eh_frame_p) |
2020 | { | |
cfc14b3a MK |
2021 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
2022 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
2023 | } | |
2024 | ||
6896c0c7 RH |
2025 | /* In either case, validate the result is still within the section. */ |
2026 | if (cie_pointer >= unit->dwarf_frame_size) | |
2027 | return NULL; | |
2028 | ||
8d749320 | 2029 | fde = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_fde); |
b01c8410 | 2030 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2031 | if (fde->cie == NULL) |
2032 | { | |
2033 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
2034 | eh_frame_p, cie_table, fde_table, |
2035 | EH_CIE_TYPE_ID); | |
b01c8410 | 2036 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2037 | } |
2038 | ||
2039 | gdb_assert (fde->cie != NULL); | |
2040 | ||
3e29f34a MR |
2041 | addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
2042 | buf, &bytes_read, 0); | |
2043 | fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); | |
cfc14b3a MK |
2044 | buf += bytes_read; |
2045 | ||
2046 | fde->address_range = | |
ae0d2f24 | 2047 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 2048 | fde->cie->ptr_size, buf, &bytes_read, 0); |
3e29f34a MR |
2049 | addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); |
2050 | fde->address_range = addr - fde->initial_location; | |
cfc14b3a MK |
2051 | buf += bytes_read; |
2052 | ||
7131cb6e RH |
2053 | /* A 'z' augmentation in the CIE implies the presence of an |
2054 | augmentation field in the FDE as well. The only thing known | |
2055 | to be in here at present is the LSDA entry for EH. So we | |
2056 | can skip the whole thing. */ | |
2057 | if (fde->cie->saw_z_augmentation) | |
2058 | { | |
9fccedf7 | 2059 | uint64_t length; |
7131cb6e | 2060 | |
f664829e DE |
2061 | buf = gdb_read_uleb128 (buf, end, &length); |
2062 | if (buf == NULL) | |
2063 | return NULL; | |
2064 | buf += length; | |
6896c0c7 RH |
2065 | if (buf > end) |
2066 | return NULL; | |
7131cb6e RH |
2067 | } |
2068 | ||
cfc14b3a MK |
2069 | fde->instructions = buf; |
2070 | fde->end = end; | |
2071 | ||
4bf8967c AS |
2072 | fde->eh_frame_p = eh_frame_p; |
2073 | ||
b01c8410 | 2074 | add_fde (fde_table, fde); |
cfc14b3a MK |
2075 | } |
2076 | ||
2077 | return end; | |
2078 | } | |
6896c0c7 | 2079 | |
8bd90839 FM |
2080 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2081 | expect an FDE or a CIE. */ | |
2082 | ||
f664829e DE |
2083 | static const gdb_byte * |
2084 | decode_frame_entry (struct comp_unit *unit, const gdb_byte *start, | |
2085 | int eh_frame_p, | |
b01c8410 | 2086 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
2087 | struct dwarf2_fde_table *fde_table, |
2088 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2089 | { |
2090 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2091 | const gdb_byte *ret; |
6896c0c7 RH |
2092 | ptrdiff_t start_offset; |
2093 | ||
2094 | while (1) | |
2095 | { | |
b01c8410 | 2096 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
8bd90839 | 2097 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2098 | if (ret != NULL) |
2099 | break; | |
2100 | ||
2101 | /* We have corrupt input data of some form. */ | |
2102 | ||
2103 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2104 | and mismatches wrt padding and alignment of debug sections. */ | |
2105 | /* Note that there is no requirement in the standard for any | |
2106 | alignment at all in the frame unwind sections. Testing for | |
2107 | alignment before trying to interpret data would be incorrect. | |
2108 | ||
2109 | However, GCC traditionally arranged for frame sections to be | |
2110 | sized such that the FDE length and CIE fields happen to be | |
2111 | aligned (in theory, for performance). This, unfortunately, | |
2112 | was done with .align directives, which had the side effect of | |
2113 | forcing the section to be aligned by the linker. | |
2114 | ||
2115 | This becomes a problem when you have some other producer that | |
2116 | creates frame sections that are not as strictly aligned. That | |
2117 | produces a hole in the frame info that gets filled by the | |
2118 | linker with zeros. | |
2119 | ||
2120 | The GCC behaviour is arguably a bug, but it's effectively now | |
2121 | part of the ABI, so we're now stuck with it, at least at the | |
2122 | object file level. A smart linker may decide, in the process | |
2123 | of compressing duplicate CIE information, that it can rewrite | |
2124 | the entire output section without this extra padding. */ | |
2125 | ||
2126 | start_offset = start - unit->dwarf_frame_buffer; | |
2127 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2128 | { | |
2129 | start += 4 - (start_offset & 3); | |
2130 | workaround = ALIGN4; | |
2131 | continue; | |
2132 | } | |
2133 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2134 | { | |
2135 | start += 8 - (start_offset & 7); | |
2136 | workaround = ALIGN8; | |
2137 | continue; | |
2138 | } | |
2139 | ||
2140 | /* Nothing left to try. Arrange to return as if we've consumed | |
2141 | the entire input section. Hopefully we'll get valid info from | |
2142 | the other of .debug_frame/.eh_frame. */ | |
2143 | workaround = FAIL; | |
2144 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2145 | break; | |
2146 | } | |
2147 | ||
2148 | switch (workaround) | |
2149 | { | |
2150 | case NONE: | |
2151 | break; | |
2152 | ||
2153 | case ALIGN4: | |
b98664d3 | 2154 | complaint (_("\ |
3e43a32a | 2155 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
2156 | unit->dwarf_frame_section->owner->filename, |
2157 | unit->dwarf_frame_section->name); | |
2158 | break; | |
2159 | ||
2160 | case ALIGN8: | |
b98664d3 | 2161 | complaint (_("\ |
3e43a32a | 2162 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
2163 | unit->dwarf_frame_section->owner->filename, |
2164 | unit->dwarf_frame_section->name); | |
2165 | break; | |
2166 | ||
2167 | default: | |
b98664d3 | 2168 | complaint (_("Corrupt data in %s:%s"), |
6896c0c7 RH |
2169 | unit->dwarf_frame_section->owner->filename, |
2170 | unit->dwarf_frame_section->name); | |
2171 | break; | |
2172 | } | |
2173 | ||
2174 | return ret; | |
2175 | } | |
cfc14b3a | 2176 | \f |
b01c8410 PP |
2177 | static int |
2178 | qsort_fde_cmp (const void *a, const void *b) | |
2179 | { | |
2180 | struct dwarf2_fde *aa = *(struct dwarf2_fde **)a; | |
2181 | struct dwarf2_fde *bb = *(struct dwarf2_fde **)b; | |
e5af178f | 2182 | |
b01c8410 | 2183 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2184 | { |
2185 | if (aa->address_range != bb->address_range | |
2186 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2187 | /* Linker bug, e.g. gold/10400. | |
2188 | Work around it by keeping stable sort order. */ | |
2189 | return (a < b) ? -1 : 1; | |
2190 | else | |
2191 | /* Put eh_frame entries after debug_frame ones. */ | |
2192 | return aa->eh_frame_p - bb->eh_frame_p; | |
2193 | } | |
b01c8410 PP |
2194 | |
2195 | return (aa->initial_location < bb->initial_location) ? -1 : 1; | |
2196 | } | |
2197 | ||
cfc14b3a MK |
2198 | void |
2199 | dwarf2_build_frame_info (struct objfile *objfile) | |
2200 | { | |
ae0d2f24 | 2201 | struct comp_unit *unit; |
f664829e | 2202 | const gdb_byte *frame_ptr; |
b01c8410 PP |
2203 | struct dwarf2_cie_table cie_table; |
2204 | struct dwarf2_fde_table fde_table; | |
be391dca | 2205 | struct dwarf2_fde_table *fde_table2; |
b01c8410 PP |
2206 | |
2207 | cie_table.num_entries = 0; | |
2208 | cie_table.entries = NULL; | |
2209 | ||
2210 | fde_table.num_entries = 0; | |
2211 | fde_table.entries = NULL; | |
cfc14b3a MK |
2212 | |
2213 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
e39db4db | 2214 | unit = XOBNEW (&objfile->objfile_obstack, comp_unit); |
ae0d2f24 UW |
2215 | unit->abfd = objfile->obfd; |
2216 | unit->objfile = objfile; | |
2217 | unit->dbase = 0; | |
2218 | unit->tbase = 0; | |
cfc14b3a | 2219 | |
d40102a1 | 2220 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2221 | { |
d40102a1 JB |
2222 | /* Do not read .eh_frame from separate file as they must be also |
2223 | present in the main file. */ | |
2224 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, | |
2225 | &unit->dwarf_frame_section, | |
2226 | &unit->dwarf_frame_buffer, | |
2227 | &unit->dwarf_frame_size); | |
2228 | if (unit->dwarf_frame_size) | |
b01c8410 | 2229 | { |
d40102a1 JB |
2230 | asection *got, *txt; |
2231 | ||
2232 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2233 | that is used for the i386/amd64 target, which currently is | |
2234 | the only target in GCC that supports/uses the | |
2235 | DW_EH_PE_datarel encoding. */ | |
2236 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2237 | if (got) | |
2238 | unit->dbase = got->vma; | |
2239 | ||
2240 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2241 | so far. */ | |
2242 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2243 | if (txt) | |
2244 | unit->tbase = txt->vma; | |
2245 | ||
492d29ea | 2246 | TRY |
8bd90839 FM |
2247 | { |
2248 | frame_ptr = unit->dwarf_frame_buffer; | |
2249 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2250 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, | |
2251 | &cie_table, &fde_table, | |
2252 | EH_CIE_OR_FDE_TYPE_ID); | |
2253 | } | |
2254 | ||
492d29ea | 2255 | CATCH (e, RETURN_MASK_ERROR) |
8bd90839 FM |
2256 | { |
2257 | warning (_("skipping .eh_frame info of %s: %s"), | |
4262abfb | 2258 | objfile_name (objfile), e.message); |
8bd90839 FM |
2259 | |
2260 | if (fde_table.num_entries != 0) | |
2261 | { | |
2262 | xfree (fde_table.entries); | |
2263 | fde_table.entries = NULL; | |
2264 | fde_table.num_entries = 0; | |
2265 | } | |
2266 | /* The cie_table is discarded by the next if. */ | |
2267 | } | |
492d29ea | 2268 | END_CATCH |
d40102a1 JB |
2269 | |
2270 | if (cie_table.num_entries != 0) | |
2271 | { | |
2272 | /* Reinit cie_table: debug_frame has different CIEs. */ | |
2273 | xfree (cie_table.entries); | |
2274 | cie_table.num_entries = 0; | |
2275 | cie_table.entries = NULL; | |
2276 | } | |
b01c8410 | 2277 | } |
cfc14b3a MK |
2278 | } |
2279 | ||
3017a003 | 2280 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dce234bc PP |
2281 | &unit->dwarf_frame_section, |
2282 | &unit->dwarf_frame_buffer, | |
2283 | &unit->dwarf_frame_size); | |
2284 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2285 | { |
8bd90839 FM |
2286 | int num_old_fde_entries = fde_table.num_entries; |
2287 | ||
492d29ea | 2288 | TRY |
8bd90839 FM |
2289 | { |
2290 | frame_ptr = unit->dwarf_frame_buffer; | |
2291 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2292 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, | |
2293 | &cie_table, &fde_table, | |
2294 | EH_CIE_OR_FDE_TYPE_ID); | |
2295 | } | |
492d29ea | 2296 | CATCH (e, RETURN_MASK_ERROR) |
8bd90839 FM |
2297 | { |
2298 | warning (_("skipping .debug_frame info of %s: %s"), | |
4262abfb | 2299 | objfile_name (objfile), e.message); |
8bd90839 FM |
2300 | |
2301 | if (fde_table.num_entries != 0) | |
2302 | { | |
2303 | fde_table.num_entries = num_old_fde_entries; | |
2304 | if (num_old_fde_entries == 0) | |
2305 | { | |
2306 | xfree (fde_table.entries); | |
2307 | fde_table.entries = NULL; | |
2308 | } | |
2309 | else | |
2310 | { | |
224c3ddb SM |
2311 | fde_table.entries |
2312 | = XRESIZEVEC (struct dwarf2_fde *, fde_table.entries, | |
2313 | fde_table.num_entries); | |
8bd90839 FM |
2314 | } |
2315 | } | |
2316 | fde_table.num_entries = num_old_fde_entries; | |
2317 | /* The cie_table is discarded by the next if. */ | |
2318 | } | |
492d29ea | 2319 | END_CATCH |
b01c8410 PP |
2320 | } |
2321 | ||
2322 | /* Discard the cie_table, it is no longer needed. */ | |
2323 | if (cie_table.num_entries != 0) | |
2324 | { | |
2325 | xfree (cie_table.entries); | |
2326 | cie_table.entries = NULL; /* Paranoia. */ | |
2327 | cie_table.num_entries = 0; /* Paranoia. */ | |
2328 | } | |
2329 | ||
be391dca | 2330 | /* Copy fde_table to obstack: it is needed at runtime. */ |
8d749320 | 2331 | fde_table2 = XOBNEW (&objfile->objfile_obstack, struct dwarf2_fde_table); |
be391dca TT |
2332 | |
2333 | if (fde_table.num_entries == 0) | |
2334 | { | |
2335 | fde_table2->entries = NULL; | |
2336 | fde_table2->num_entries = 0; | |
2337 | } | |
2338 | else | |
b01c8410 | 2339 | { |
875cdfbb PA |
2340 | struct dwarf2_fde *fde_prev = NULL; |
2341 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2342 | int i; | |
b01c8410 PP |
2343 | |
2344 | /* Prepare FDE table for lookups. */ | |
2345 | qsort (fde_table.entries, fde_table.num_entries, | |
2346 | sizeof (fde_table.entries[0]), qsort_fde_cmp); | |
2347 | ||
875cdfbb PA |
2348 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2349 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2350 | ranges because there's no relocation there. It's (offset, | |
2351 | length), not (start, end). On targets where address zero is | |
2352 | just another valid address this can be a problem, since the | |
2353 | FDEs appear to be non-empty in the output --- we could pick | |
2354 | out the wrong FDE. To work around this, when overlaps are | |
2355 | detected, we prefer FDEs that do not start at zero. | |
2356 | ||
2357 | Start by finding the first FDE with non-zero start. Below | |
2358 | we'll discard all FDEs that start at zero and overlap this | |
2359 | one. */ | |
2360 | for (i = 0; i < fde_table.num_entries; i++) | |
2361 | { | |
2362 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2363 | |
875cdfbb PA |
2364 | if (fde->initial_location != 0) |
2365 | { | |
2366 | first_non_zero_fde = fde; | |
2367 | break; | |
2368 | } | |
2369 | } | |
2370 | ||
2371 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2372 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2373 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2374 | fde_table2->num_entries = 0; |
875cdfbb PA |
2375 | for (i = 0; i < fde_table.num_entries; i++) |
2376 | { | |
2377 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2378 | ||
2379 | if (fde->initial_location == 0 | |
2380 | && first_non_zero_fde != NULL | |
2381 | && (first_non_zero_fde->initial_location | |
2382 | < fde->initial_location + fde->address_range)) | |
2383 | continue; | |
2384 | ||
2385 | if (fde_prev != NULL | |
2386 | && fde_prev->initial_location == fde->initial_location) | |
2387 | continue; | |
2388 | ||
2389 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2390 | sizeof (fde_table.entries[0])); | |
2391 | ++fde_table2->num_entries; | |
2392 | fde_prev = fde; | |
2393 | } | |
224c3ddb SM |
2394 | fde_table2->entries |
2395 | = (struct dwarf2_fde **) obstack_finish (&objfile->objfile_obstack); | |
b01c8410 PP |
2396 | |
2397 | /* Discard the original fde_table. */ | |
2398 | xfree (fde_table.entries); | |
cfc14b3a | 2399 | } |
be391dca TT |
2400 | |
2401 | set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2); | |
cfc14b3a | 2402 | } |
0d0e1a63 | 2403 | |
3c3bb058 AB |
2404 | /* Handle 'maintenance show dwarf unwinders'. */ |
2405 | ||
2406 | static void | |
2407 | show_dwarf_unwinders_enabled_p (struct ui_file *file, int from_tty, | |
2408 | struct cmd_list_element *c, | |
2409 | const char *value) | |
2410 | { | |
2411 | fprintf_filtered (file, | |
2412 | _("The DWARF stack unwinders are currently %s.\n"), | |
2413 | value); | |
2414 | } | |
2415 | ||
0d0e1a63 MK |
2416 | void |
2417 | _initialize_dwarf2_frame (void) | |
2418 | { | |
030f20e1 | 2419 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2420 | dwarf2_frame_objfile_data = register_objfile_data (); |
1c90d9f0 | 2421 | |
3c3bb058 AB |
2422 | add_setshow_boolean_cmd ("unwinders", class_obscure, |
2423 | &dwarf2_frame_unwinders_enabled_p , _("\ | |
2424 | Set whether the DWARF stack frame unwinders are used."), _("\ | |
2425 | Show whether the DWARF stack frame unwinders are used."), _("\ | |
2426 | When enabled the DWARF stack frame unwinders can be used for architectures\n\ | |
2427 | that support the DWARF unwinders. Enabling the DWARF unwinders for an\n\ | |
2428 | architecture that doesn't support them will have no effect."), | |
2429 | NULL, | |
2430 | show_dwarf_unwinders_enabled_p, | |
2431 | &set_dwarf_cmdlist, | |
2432 | &show_dwarf_cmdlist); | |
2433 | ||
1c90d9f0 | 2434 | #if GDB_SELF_TEST |
1526853e SM |
2435 | selftests::register_test_foreach_arch ("execute_cfa_program", |
2436 | selftests::execute_cfa_program_test); | |
1c90d9f0 | 2437 | #endif |
0d0e1a63 | 2438 | } |