Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
88b9d363 | 3 | Copyright (C) 2003-2022 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" | |
82ca8957 | 23 | #include "dwarf2/expr.h" |
4de283e4 | 24 | #include "dwarf2.h" |
f4382c45 | 25 | #include "dwarf2/leb.h" |
4de283e4 | 26 | #include "frame.h" |
cfc14b3a MK |
27 | #include "frame-base.h" |
28 | #include "frame-unwind.h" | |
29 | #include "gdbcore.h" | |
30 | #include "gdbtypes.h" | |
4de283e4 | 31 | #include "symtab.h" |
cfc14b3a MK |
32 | #include "objfiles.h" |
33 | #include "regcache.h" | |
f2da6b3a | 34 | #include "value.h" |
4de283e4 | 35 | #include "record.h" |
cfc14b3a | 36 | |
4de283e4 | 37 | #include "complaints.h" |
82ca8957 TT |
38 | #include "dwarf2/frame.h" |
39 | #include "dwarf2/read.h" | |
70182375 | 40 | #include "dwarf2/public.h" |
4de283e4 | 41 | #include "ax.h" |
82ca8957 TT |
42 | #include "dwarf2/loc.h" |
43 | #include "dwarf2/frame-tailcall.h" | |
35e65c49 | 44 | #include "gdbsupport/gdb_binary_search.h" |
1c90d9f0 | 45 | #if GDB_SELF_TEST |
268a13a5 | 46 | #include "gdbsupport/selftest.h" |
1c90d9f0 YQ |
47 | #include "selftest-arch.h" |
48 | #endif | |
93878f47 | 49 | #include <unordered_map> |
cfc14b3a | 50 | |
39ef2f62 CB |
51 | #include <algorithm> |
52 | ||
ae0d2f24 UW |
53 | struct comp_unit; |
54 | ||
cfc14b3a MK |
55 | /* Call Frame Information (CFI). */ |
56 | ||
57 | /* Common Information Entry (CIE). */ | |
58 | ||
59 | struct dwarf2_cie | |
60 | { | |
ae0d2f24 UW |
61 | /* Computation Unit for this CIE. */ |
62 | struct comp_unit *unit; | |
63 | ||
cfc14b3a MK |
64 | /* Offset into the .debug_frame section where this CIE was found. |
65 | Used to identify this CIE. */ | |
66 | ULONGEST cie_pointer; | |
67 | ||
68 | /* Constant that is factored out of all advance location | |
69 | instructions. */ | |
70 | ULONGEST code_alignment_factor; | |
71 | ||
72 | /* Constants that is factored out of all offset instructions. */ | |
73 | LONGEST data_alignment_factor; | |
74 | ||
75 | /* Return address column. */ | |
76 | ULONGEST return_address_register; | |
77 | ||
78 | /* Instruction sequence to initialize a register set. */ | |
f664829e DE |
79 | const gdb_byte *initial_instructions; |
80 | const gdb_byte *end; | |
cfc14b3a | 81 | |
303b6f5d DJ |
82 | /* Saved augmentation, in case it's needed later. */ |
83 | char *augmentation; | |
84 | ||
cfc14b3a | 85 | /* Encoding of addresses. */ |
852483bc | 86 | gdb_byte encoding; |
cfc14b3a | 87 | |
ae0d2f24 UW |
88 | /* Target address size in bytes. */ |
89 | int addr_size; | |
90 | ||
0963b4bd | 91 | /* Target pointer size in bytes. */ |
8da614df CV |
92 | int ptr_size; |
93 | ||
7131cb6e RH |
94 | /* True if a 'z' augmentation existed. */ |
95 | unsigned char saw_z_augmentation; | |
96 | ||
56c987f6 AO |
97 | /* True if an 'S' augmentation existed. */ |
98 | unsigned char signal_frame; | |
99 | ||
303b6f5d DJ |
100 | /* The version recorded in the CIE. */ |
101 | unsigned char version; | |
2dc7f7b3 TT |
102 | |
103 | /* The segment size. */ | |
104 | unsigned char segment_size; | |
b01c8410 | 105 | }; |
303b6f5d | 106 | |
93878f47 TT |
107 | /* The CIE table is used to find CIEs during parsing, but then |
108 | discarded. It maps from the CIE's offset to the CIE. */ | |
109 | typedef std::unordered_map<ULONGEST, dwarf2_cie *> dwarf2_cie_table; | |
cfc14b3a MK |
110 | |
111 | /* Frame Description Entry (FDE). */ | |
112 | ||
113 | struct dwarf2_fde | |
114 | { | |
115 | /* CIE for this FDE. */ | |
116 | struct dwarf2_cie *cie; | |
117 | ||
118 | /* First location associated with this FDE. */ | |
119 | CORE_ADDR initial_location; | |
120 | ||
121 | /* Number of bytes of program instructions described by this FDE. */ | |
122 | CORE_ADDR address_range; | |
123 | ||
124 | /* Instruction sequence. */ | |
f664829e DE |
125 | const gdb_byte *instructions; |
126 | const gdb_byte *end; | |
cfc14b3a | 127 | |
4bf8967c AS |
128 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
129 | section. */ | |
130 | unsigned char eh_frame_p; | |
b01c8410 | 131 | }; |
4bf8967c | 132 | |
a9d65418 | 133 | typedef std::vector<dwarf2_fde *> dwarf2_fde_table; |
cfc14b3a | 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 | { | |
a7a3ae5c | 140 | comp_unit (struct objfile *objf) |
21982304 | 141 | : abfd (objf->obfd) |
a7a3ae5c TT |
142 | { |
143 | } | |
144 | ||
ae0d2f24 UW |
145 | /* Keep the bfd convenient. */ |
146 | bfd *abfd; | |
147 | ||
ae0d2f24 | 148 | /* Pointer to the .debug_frame section loaded into memory. */ |
a7a3ae5c | 149 | const gdb_byte *dwarf_frame_buffer = nullptr; |
ae0d2f24 UW |
150 | |
151 | /* Length of the loaded .debug_frame section. */ | |
a7a3ae5c | 152 | bfd_size_type dwarf_frame_size = 0; |
ae0d2f24 UW |
153 | |
154 | /* Pointer to the .debug_frame section. */ | |
a7a3ae5c | 155 | asection *dwarf_frame_section = nullptr; |
ae0d2f24 UW |
156 | |
157 | /* Base for DW_EH_PE_datarel encodings. */ | |
a7a3ae5c | 158 | bfd_vma dbase = 0; |
ae0d2f24 UW |
159 | |
160 | /* Base for DW_EH_PE_textrel encodings. */ | |
a7a3ae5c TT |
161 | bfd_vma tbase = 0; |
162 | ||
163 | /* The FDE table. */ | |
164 | dwarf2_fde_table fde_table; | |
0d404d44 TT |
165 | |
166 | /* Hold data used by this module. */ | |
167 | auto_obstack obstack; | |
ae0d2f24 UW |
168 | }; |
169 | ||
89b07335 SM |
170 | static struct dwarf2_fde *dwarf2_frame_find_fde |
171 | (CORE_ADDR *pc, dwarf2_per_objfile **out_per_objfile); | |
4fc771b8 DJ |
172 | |
173 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
174 | int eh_frame_p); | |
ae0d2f24 UW |
175 | |
176 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 177 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
178 | unsigned int *bytes_read_ptr, |
179 | CORE_ADDR func_base); | |
cfc14b3a MK |
180 | \f |
181 | ||
3c3bb058 | 182 | /* See dwarf2-frame.h. */ |
491144b5 | 183 | bool dwarf2_frame_unwinders_enabled_p = true; |
3c3bb058 | 184 | |
cfc14b3a MK |
185 | /* Store the length the expression for the CFA in the `cfa_reg' field, |
186 | which is unused in that case. */ | |
187 | #define cfa_exp_len cfa_reg | |
188 | ||
afe37d6b YQ |
189 | dwarf2_frame_state::dwarf2_frame_state (CORE_ADDR pc_, struct dwarf2_cie *cie) |
190 | : pc (pc_), data_align (cie->data_alignment_factor), | |
191 | code_align (cie->code_alignment_factor), | |
192 | retaddr_column (cie->return_address_register) | |
cfc14b3a | 193 | { |
afe37d6b | 194 | } |
cfc14b3a MK |
195 | \f |
196 | ||
197 | /* Helper functions for execute_stack_op. */ | |
198 | ||
199 | static CORE_ADDR | |
192ca6d8 | 200 | read_addr_from_reg (struct frame_info *this_frame, int reg) |
cfc14b3a | 201 | { |
4a4e5149 | 202 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
0fde2c53 | 203 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); |
f2da6b3a | 204 | |
2ed3c037 | 205 | return address_from_register (regnum, this_frame); |
cfc14b3a MK |
206 | } |
207 | ||
a6a5a945 LM |
208 | /* Execute the required actions for both the DW_CFA_restore and |
209 | DW_CFA_restore_extended instructions. */ | |
210 | static void | |
211 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
212 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
213 | { | |
214 | ULONGEST reg; | |
215 | ||
a6a5a945 | 216 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); |
1c90d9f0 | 217 | fs->regs.alloc_regs (reg + 1); |
a6a5a945 LM |
218 | |
219 | /* Check if this register was explicitly initialized in the | |
220 | CIE initial instructions. If not, default the rule to | |
221 | UNSPECIFIED. */ | |
780942fc | 222 | if (reg < fs->initial.reg.size ()) |
a6a5a945 LM |
223 | fs->regs.reg[reg] = fs->initial.reg[reg]; |
224 | else | |
225 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
226 | ||
227 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
0fde2c53 DE |
228 | { |
229 | int regnum = dwarf_reg_to_regnum (gdbarch, reg); | |
230 | ||
b98664d3 | 231 | complaint (_("\ |
a6a5a945 | 232 | incomplete CFI data; DW_CFA_restore unspecified\n\ |
5af949e3 | 233 | register %s (#%d) at %s"), |
0fde2c53 DE |
234 | gdbarch_register_name (gdbarch, regnum), regnum, |
235 | paddress (gdbarch, fs->pc)); | |
236 | } | |
a6a5a945 LM |
237 | } |
238 | ||
192ca6d8 | 239 | class dwarf_expr_executor : public dwarf_expr_context |
9e8b7a03 | 240 | { |
89b07335 SM |
241 | public: |
242 | ||
243 | dwarf_expr_executor (dwarf2_per_objfile *per_objfile) | |
244 | : dwarf_expr_context (per_objfile) | |
245 | {} | |
192ca6d8 TT |
246 | |
247 | struct frame_info *this_frame; | |
248 | ||
632e107b | 249 | CORE_ADDR read_addr_from_reg (int reg) override |
192ca6d8 TT |
250 | { |
251 | return ::read_addr_from_reg (this_frame, reg); | |
252 | } | |
253 | ||
632e107b | 254 | struct value *get_reg_value (struct type *type, int reg) override |
192ca6d8 TT |
255 | { |
256 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
257 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); | |
258 | ||
259 | return value_from_register (type, regnum, this_frame); | |
260 | } | |
261 | ||
632e107b | 262 | void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) override |
192ca6d8 TT |
263 | { |
264 | read_memory (addr, buf, len); | |
265 | } | |
befbff86 | 266 | |
632e107b | 267 | void get_frame_base (const gdb_byte **start, size_t *length) override |
befbff86 TT |
268 | { |
269 | invalid ("DW_OP_fbreg"); | |
270 | } | |
271 | ||
272 | void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, | |
273 | union call_site_parameter_u kind_u, | |
632e107b | 274 | int deref_size) override |
befbff86 | 275 | { |
216f72a1 | 276 | invalid ("DW_OP_entry_value"); |
befbff86 TT |
277 | } |
278 | ||
632e107b | 279 | CORE_ADDR get_object_address () override |
befbff86 TT |
280 | { |
281 | invalid ("DW_OP_push_object_address"); | |
282 | } | |
283 | ||
632e107b | 284 | CORE_ADDR get_frame_cfa () override |
befbff86 TT |
285 | { |
286 | invalid ("DW_OP_call_frame_cfa"); | |
287 | } | |
288 | ||
632e107b | 289 | CORE_ADDR get_tls_address (CORE_ADDR offset) override |
befbff86 TT |
290 | { |
291 | invalid ("DW_OP_form_tls_address"); | |
292 | } | |
293 | ||
632e107b | 294 | void dwarf_call (cu_offset die_offset) override |
befbff86 TT |
295 | { |
296 | invalid ("DW_OP_call*"); | |
297 | } | |
298 | ||
a6b786da KB |
299 | struct value *dwarf_variable_value (sect_offset sect_off) override |
300 | { | |
301 | invalid ("DW_OP_GNU_variable_value"); | |
302 | } | |
303 | ||
632e107b | 304 | CORE_ADDR get_addr_index (unsigned int index) override |
befbff86 | 305 | { |
336d760d | 306 | invalid ("DW_OP_addrx or DW_OP_GNU_addr_index"); |
befbff86 TT |
307 | } |
308 | ||
309 | private: | |
310 | ||
311 | void invalid (const char *op) ATTRIBUTE_NORETURN | |
312 | { | |
313 | error (_("%s is invalid in this context"), op); | |
314 | } | |
9e8b7a03 JK |
315 | }; |
316 | ||
cfc14b3a | 317 | static CORE_ADDR |
0d45f56e | 318 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
89b07335 SM |
319 | struct frame_info *this_frame, CORE_ADDR initial, |
320 | int initial_in_stack_memory, dwarf2_per_objfile *per_objfile) | |
cfc14b3a | 321 | { |
cfc14b3a MK |
322 | CORE_ADDR result; |
323 | ||
89b07335 | 324 | dwarf_expr_executor ctx (per_objfile); |
eb115069 | 325 | scoped_value_mark free_values; |
4a227398 | 326 | |
192ca6d8 | 327 | ctx.this_frame = this_frame; |
718b9626 TT |
328 | ctx.gdbarch = get_frame_arch (this_frame); |
329 | ctx.addr_size = addr_size; | |
330 | ctx.ref_addr_size = -1; | |
cfc14b3a | 331 | |
595d2e30 TT |
332 | ctx.push_address (initial, initial_in_stack_memory); |
333 | ctx.eval (exp, len); | |
cfc14b3a | 334 | |
718b9626 | 335 | if (ctx.location == DWARF_VALUE_MEMORY) |
595d2e30 | 336 | result = ctx.fetch_address (0); |
718b9626 | 337 | else if (ctx.location == DWARF_VALUE_REGISTER) |
192ca6d8 | 338 | result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0))); |
f2c7657e | 339 | else |
cec03d70 TT |
340 | { |
341 | /* This is actually invalid DWARF, but if we ever do run across | |
342 | it somehow, we might as well support it. So, instead, report | |
343 | it as unimplemented. */ | |
3e43a32a MS |
344 | error (_("\ |
345 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 346 | } |
cfc14b3a | 347 | |
cfc14b3a MK |
348 | return result; |
349 | } | |
350 | \f | |
351 | ||
111c6489 JK |
352 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
353 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
354 | execution has stopped, one can resume it on the next call. */ | |
355 | ||
356 | static const gdb_byte * | |
0d45f56e | 357 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff | 358 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
21982304 TT |
359 | CORE_ADDR pc, struct dwarf2_frame_state *fs, |
360 | CORE_ADDR text_offset) | |
cfc14b3a | 361 | { |
ae0d2f24 | 362 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 363 | unsigned int bytes_read; |
e17a4113 | 364 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
365 | |
366 | while (insn_ptr < insn_end && fs->pc <= pc) | |
367 | { | |
852483bc | 368 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
369 | uint64_t utmp, reg; |
370 | int64_t offset; | |
cfc14b3a MK |
371 | |
372 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
373 | fs->pc += (insn & 0x3f) * fs->code_align; | |
374 | else if ((insn & 0xc0) == DW_CFA_offset) | |
375 | { | |
376 | reg = insn & 0x3f; | |
4fc771b8 | 377 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 378 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 379 | offset = utmp * fs->data_align; |
1c90d9f0 | 380 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 381 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
382 | fs->regs.reg[reg].loc.offset = offset; |
383 | } | |
384 | else if ((insn & 0xc0) == DW_CFA_restore) | |
385 | { | |
cfc14b3a | 386 | reg = insn & 0x3f; |
a6a5a945 | 387 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
388 | } |
389 | else | |
390 | { | |
391 | switch (insn) | |
392 | { | |
393 | case DW_CFA_set_loc: | |
ae0d2f24 | 394 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 395 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 | 396 | &bytes_read, fde->initial_location); |
21982304 TT |
397 | /* Apply the text offset for relocatable objects. */ |
398 | fs->pc += text_offset; | |
cfc14b3a MK |
399 | insn_ptr += bytes_read; |
400 | break; | |
401 | ||
402 | case DW_CFA_advance_loc1: | |
e17a4113 | 403 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
404 | fs->pc += utmp * fs->code_align; |
405 | insn_ptr++; | |
406 | break; | |
407 | case DW_CFA_advance_loc2: | |
e17a4113 | 408 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
409 | fs->pc += utmp * fs->code_align; |
410 | insn_ptr += 2; | |
411 | break; | |
412 | case DW_CFA_advance_loc4: | |
e17a4113 | 413 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
414 | fs->pc += utmp * fs->code_align; |
415 | insn_ptr += 4; | |
416 | break; | |
417 | ||
418 | case DW_CFA_offset_extended: | |
f664829e | 419 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 420 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 421 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 422 | offset = utmp * fs->data_align; |
1c90d9f0 | 423 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 424 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
425 | fs->regs.reg[reg].loc.offset = offset; |
426 | break; | |
427 | ||
428 | case DW_CFA_restore_extended: | |
f664829e | 429 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 430 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
431 | break; |
432 | ||
433 | case DW_CFA_undefined: | |
f664829e | 434 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 435 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 436 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 437 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
438 | break; |
439 | ||
440 | case DW_CFA_same_value: | |
f664829e | 441 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 442 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 443 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 444 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
445 | break; |
446 | ||
447 | case DW_CFA_register: | |
f664829e | 448 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 449 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 450 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 451 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
1c90d9f0 | 452 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 453 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
454 | fs->regs.reg[reg].loc.reg = utmp; |
455 | break; | |
456 | ||
457 | case DW_CFA_remember_state: | |
458 | { | |
459 | struct dwarf2_frame_state_reg_info *new_rs; | |
460 | ||
1c90d9f0 | 461 | new_rs = new dwarf2_frame_state_reg_info (fs->regs); |
cfc14b3a MK |
462 | fs->regs.prev = new_rs; |
463 | } | |
464 | break; | |
465 | ||
466 | case DW_CFA_restore_state: | |
467 | { | |
468 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
469 | ||
50ea7769 MK |
470 | if (old_rs == NULL) |
471 | { | |
b98664d3 | 472 | complaint (_("\ |
5af949e3 UW |
473 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
474 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
475 | } |
476 | else | |
1c90d9f0 | 477 | fs->regs = std::move (*old_rs); |
cfc14b3a MK |
478 | } |
479 | break; | |
480 | ||
481 | case DW_CFA_def_cfa: | |
f664829e DE |
482 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
483 | fs->regs.cfa_reg = reg; | |
484 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
485 | |
486 | if (fs->armcc_cfa_offsets_sf) | |
487 | utmp *= fs->data_align; | |
488 | ||
2fd481e1 PP |
489 | fs->regs.cfa_offset = utmp; |
490 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
491 | break; |
492 | ||
493 | case DW_CFA_def_cfa_register: | |
f664829e DE |
494 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
495 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
dda83cd7 | 496 | eh_frame_p); |
2fd481e1 | 497 | fs->regs.cfa_how = CFA_REG_OFFSET; |
cfc14b3a MK |
498 | break; |
499 | ||
500 | case DW_CFA_def_cfa_offset: | |
f664829e | 501 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
502 | |
503 | if (fs->armcc_cfa_offsets_sf) | |
504 | utmp *= fs->data_align; | |
505 | ||
2fd481e1 | 506 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
507 | /* cfa_how deliberately not set. */ |
508 | break; | |
509 | ||
a8504492 MK |
510 | case DW_CFA_nop: |
511 | break; | |
512 | ||
cfc14b3a | 513 | case DW_CFA_def_cfa_expression: |
f664829e DE |
514 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
515 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
516 | fs->regs.cfa_exp = insn_ptr; |
517 | fs->regs.cfa_how = CFA_EXP; | |
518 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
519 | break; |
520 | ||
521 | case DW_CFA_expression: | |
f664829e | 522 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 523 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 524 | fs->regs.alloc_regs (reg + 1); |
f664829e | 525 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
526 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
527 | fs->regs.reg[reg].loc.exp.len = utmp; | |
05cbe71a | 528 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
529 | insn_ptr += utmp; |
530 | break; | |
531 | ||
a8504492 | 532 | case DW_CFA_offset_extended_sf: |
f664829e | 533 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 534 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 535 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 536 | offset *= fs->data_align; |
1c90d9f0 | 537 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 538 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
539 | fs->regs.reg[reg].loc.offset = offset; |
540 | break; | |
541 | ||
46ea248b | 542 | case DW_CFA_val_offset: |
f664829e | 543 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 544 | fs->regs.alloc_regs (reg + 1); |
f664829e | 545 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
546 | offset = utmp * fs->data_align; |
547 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
548 | fs->regs.reg[reg].loc.offset = offset; | |
549 | break; | |
550 | ||
551 | case DW_CFA_val_offset_sf: | |
f664829e | 552 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 553 | fs->regs.alloc_regs (reg + 1); |
f664829e | 554 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
555 | offset *= fs->data_align; |
556 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
557 | fs->regs.reg[reg].loc.offset = offset; | |
558 | break; | |
559 | ||
560 | case DW_CFA_val_expression: | |
f664829e | 561 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 562 | fs->regs.alloc_regs (reg + 1); |
f664829e | 563 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
564 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
565 | fs->regs.reg[reg].loc.exp.len = utmp; | |
46ea248b AO |
566 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; |
567 | insn_ptr += utmp; | |
568 | break; | |
569 | ||
a8504492 | 570 | case DW_CFA_def_cfa_sf: |
f664829e DE |
571 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
572 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
dda83cd7 | 573 | eh_frame_p); |
f664829e | 574 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
575 | fs->regs.cfa_offset = offset * fs->data_align; |
576 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
577 | break; |
578 | ||
579 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 580 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 581 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 582 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
583 | break; |
584 | ||
585 | case DW_CFA_GNU_args_size: | |
586 | /* Ignored. */ | |
f664829e | 587 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
588 | break; |
589 | ||
58894217 | 590 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 591 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 592 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
593 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
594 | offset = utmp * fs->data_align; | |
1c90d9f0 | 595 | fs->regs.alloc_regs (reg + 1); |
58894217 JK |
596 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
597 | fs->regs.reg[reg].loc.offset = -offset; | |
598 | break; | |
599 | ||
cfc14b3a | 600 | default: |
b41c5a85 JW |
601 | if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user) |
602 | { | |
603 | /* Handle vendor-specific CFI for different architectures. */ | |
604 | if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs)) | |
605 | error (_("Call Frame Instruction op %d in vendor extension " | |
606 | "space is not handled on this architecture."), | |
607 | insn); | |
608 | } | |
609 | else | |
610 | internal_error (__FILE__, __LINE__, | |
611 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
612 | } |
613 | } | |
614 | } | |
615 | ||
780942fc | 616 | if (fs->initial.reg.empty ()) |
111c6489 JK |
617 | { |
618 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
1c90d9f0 | 619 | delete fs->regs.prev; |
111c6489 JK |
620 | fs->regs.prev = NULL; |
621 | } | |
622 | ||
623 | return insn_ptr; | |
cfc14b3a | 624 | } |
1c90d9f0 YQ |
625 | |
626 | #if GDB_SELF_TEST | |
627 | ||
628 | namespace selftests { | |
629 | ||
630 | /* Unit test to function execute_cfa_program. */ | |
631 | ||
632 | static void | |
633 | execute_cfa_program_test (struct gdbarch *gdbarch) | |
634 | { | |
635 | struct dwarf2_fde fde; | |
636 | struct dwarf2_cie cie; | |
637 | ||
638 | memset (&fde, 0, sizeof fde); | |
639 | memset (&cie, 0, sizeof cie); | |
640 | ||
641 | cie.data_alignment_factor = -4; | |
642 | cie.code_alignment_factor = 2; | |
643 | fde.cie = &cie; | |
644 | ||
645 | dwarf2_frame_state fs (0, fde.cie); | |
646 | ||
647 | gdb_byte insns[] = | |
648 | { | |
649 | DW_CFA_def_cfa, 1, 4, /* DW_CFA_def_cfa: r1 ofs 4 */ | |
650 | DW_CFA_offset | 0x2, 1, /* DW_CFA_offset: r2 at cfa-4 */ | |
651 | DW_CFA_remember_state, | |
652 | DW_CFA_restore_state, | |
653 | }; | |
654 | ||
655 | const gdb_byte *insn_end = insns + sizeof (insns); | |
656 | const gdb_byte *out = execute_cfa_program (&fde, insns, insn_end, gdbarch, | |
21982304 | 657 | 0, &fs, 0); |
1c90d9f0 YQ |
658 | |
659 | SELF_CHECK (out == insn_end); | |
660 | SELF_CHECK (fs.pc == 0); | |
661 | ||
662 | /* The instructions above only use r1 and r2, but the register numbers | |
663 | used are adjusted by dwarf2_frame_adjust_regnum. */ | |
664 | auto r1 = dwarf2_frame_adjust_regnum (gdbarch, 1, fde.eh_frame_p); | |
665 | auto r2 = dwarf2_frame_adjust_regnum (gdbarch, 2, fde.eh_frame_p); | |
666 | ||
780942fc | 667 | SELF_CHECK (fs.regs.reg.size () == (std::max (r1, r2) + 1)); |
1c90d9f0 YQ |
668 | |
669 | SELF_CHECK (fs.regs.reg[r2].how == DWARF2_FRAME_REG_SAVED_OFFSET); | |
670 | SELF_CHECK (fs.regs.reg[r2].loc.offset == -4); | |
671 | ||
780942fc | 672 | for (auto i = 0; i < fs.regs.reg.size (); i++) |
1c90d9f0 YQ |
673 | if (i != r2) |
674 | SELF_CHECK (fs.regs.reg[i].how == DWARF2_FRAME_REG_UNSPECIFIED); | |
675 | ||
676 | SELF_CHECK (fs.regs.cfa_reg == 1); | |
677 | SELF_CHECK (fs.regs.cfa_offset == 4); | |
678 | SELF_CHECK (fs.regs.cfa_how == CFA_REG_OFFSET); | |
679 | SELF_CHECK (fs.regs.cfa_exp == NULL); | |
680 | SELF_CHECK (fs.regs.prev == NULL); | |
681 | } | |
682 | ||
683 | } // namespace selftests | |
684 | #endif /* GDB_SELF_TEST */ | |
685 | ||
8f22cb90 | 686 | \f |
cfc14b3a | 687 | |
8f22cb90 | 688 | /* Architecture-specific operations. */ |
cfc14b3a | 689 | |
8f22cb90 MK |
690 | /* Per-architecture data key. */ |
691 | static struct gdbarch_data *dwarf2_frame_data; | |
692 | ||
693 | struct dwarf2_frame_ops | |
694 | { | |
695 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
696 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
697 | struct frame_info *); | |
3ed09a32 | 698 | |
4a4e5149 | 699 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 700 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 701 | |
4fc771b8 DJ |
702 | /* Convert .eh_frame register number to DWARF register number, or |
703 | adjust .debug_frame register number. */ | |
704 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
705 | }; |
706 | ||
8f22cb90 MK |
707 | /* Default architecture-specific register state initialization |
708 | function. */ | |
709 | ||
710 | static void | |
711 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 712 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 713 | struct frame_info *this_frame) |
8f22cb90 MK |
714 | { |
715 | /* If we have a register that acts as a program counter, mark it as | |
716 | a destination for the return address. If we have a register that | |
717 | serves as the stack pointer, arrange for it to be filled with the | |
718 | call frame address (CFA). The other registers are marked as | |
719 | unspecified. | |
720 | ||
721 | We copy the return address to the program counter, since many | |
722 | parts in GDB assume that it is possible to get the return address | |
723 | by unwinding the program counter register. However, on ISA's | |
724 | with a dedicated return address register, the CFI usually only | |
725 | contains information to unwind that return address register. | |
726 | ||
727 | The reason we're treating the stack pointer special here is | |
728 | because in many cases GCC doesn't emit CFI for the stack pointer | |
729 | and implicitly assumes that it is equal to the CFA. This makes | |
730 | some sense since the DWARF specification (version 3, draft 8, | |
731 | p. 102) says that: | |
732 | ||
733 | "Typically, the CFA is defined to be the value of the stack | |
734 | pointer at the call site in the previous frame (which may be | |
735 | different from its value on entry to the current frame)." | |
736 | ||
737 | However, this isn't true for all platforms supported by GCC | |
738 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
739 | their own architecture-specific initialization function. */ | |
05cbe71a | 740 | |
ad010def | 741 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 742 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 743 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
744 | reg->how = DWARF2_FRAME_REG_CFA; |
745 | } | |
05cbe71a | 746 | |
8f22cb90 | 747 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 748 | |
8f22cb90 | 749 | static void * |
030f20e1 | 750 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
751 | { |
752 | struct dwarf2_frame_ops *ops; | |
753 | ||
030f20e1 | 754 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
755 | ops->init_reg = dwarf2_frame_default_init_reg; |
756 | return ops; | |
757 | } | |
05cbe71a | 758 | |
8f22cb90 MK |
759 | /* Set the architecture-specific register state initialization |
760 | function for GDBARCH to INIT_REG. */ | |
761 | ||
762 | void | |
763 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
764 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
765 | struct dwarf2_frame_state_reg *, |
766 | struct frame_info *)) | |
8f22cb90 | 767 | { |
9a3c8263 SM |
768 | struct dwarf2_frame_ops *ops |
769 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 770 | |
8f22cb90 MK |
771 | ops->init_reg = init_reg; |
772 | } | |
773 | ||
774 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
775 | |
776 | static void | |
777 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 778 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 779 | struct frame_info *this_frame) |
05cbe71a | 780 | { |
9a3c8263 SM |
781 | struct dwarf2_frame_ops *ops |
782 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 783 | |
4a4e5149 | 784 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 785 | } |
3ed09a32 DJ |
786 | |
787 | /* Set the architecture-specific signal trampoline recognition | |
788 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
789 | ||
790 | void | |
791 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
792 | int (*signal_frame_p) (struct gdbarch *, | |
793 | struct frame_info *)) | |
794 | { | |
9a3c8263 SM |
795 | struct dwarf2_frame_ops *ops |
796 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
797 | |
798 | ops->signal_frame_p = signal_frame_p; | |
799 | } | |
800 | ||
801 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 802 | THIS_FRAME. */ |
3ed09a32 DJ |
803 | |
804 | static int | |
805 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 806 | struct frame_info *this_frame) |
3ed09a32 | 807 | { |
9a3c8263 SM |
808 | struct dwarf2_frame_ops *ops |
809 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
810 | |
811 | if (ops->signal_frame_p == NULL) | |
812 | return 0; | |
4a4e5149 | 813 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 814 | } |
4bf8967c | 815 | |
4fc771b8 DJ |
816 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
817 | register numbers. */ | |
4bf8967c AS |
818 | |
819 | void | |
4fc771b8 DJ |
820 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
821 | int (*adjust_regnum) (struct gdbarch *, | |
822 | int, int)) | |
4bf8967c | 823 | { |
9a3c8263 SM |
824 | struct dwarf2_frame_ops *ops |
825 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 826 | |
4fc771b8 | 827 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
828 | } |
829 | ||
4fc771b8 DJ |
830 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
831 | register. */ | |
4bf8967c | 832 | |
4fc771b8 | 833 | static int |
3e43a32a MS |
834 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
835 | int regnum, int eh_frame_p) | |
4bf8967c | 836 | { |
9a3c8263 SM |
837 | struct dwarf2_frame_ops *ops |
838 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 839 | |
4fc771b8 | 840 | if (ops->adjust_regnum == NULL) |
4bf8967c | 841 | return regnum; |
4fc771b8 | 842 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 843 | } |
303b6f5d DJ |
844 | |
845 | static void | |
846 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
847 | struct dwarf2_fde *fde) | |
848 | { | |
43f3e411 | 849 | struct compunit_symtab *cust; |
303b6f5d | 850 | |
43f3e411 DE |
851 | cust = find_pc_compunit_symtab (fs->pc); |
852 | if (cust == NULL) | |
303b6f5d DJ |
853 | return; |
854 | ||
43f3e411 | 855 | if (producer_is_realview (COMPUNIT_PRODUCER (cust))) |
a6c727b2 DJ |
856 | { |
857 | if (fde->cie->version == 1) | |
858 | fs->armcc_cfa_offsets_sf = 1; | |
859 | ||
860 | if (fde->cie->version == 1) | |
861 | fs->armcc_cfa_offsets_reversed = 1; | |
862 | ||
863 | /* The reversed offset problem is present in some compilers | |
864 | using DWARF3, but it was eventually fixed. Check the ARM | |
865 | defined augmentations, which are in the format "armcc" followed | |
866 | by a list of one-character options. The "+" option means | |
867 | this problem is fixed (no quirk needed). If the armcc | |
868 | augmentation is missing, the quirk is needed. */ | |
869 | if (fde->cie->version == 3 | |
61012eef | 870 | && (!startswith (fde->cie->augmentation, "armcc") |
a6c727b2 DJ |
871 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) |
872 | fs->armcc_cfa_offsets_reversed = 1; | |
873 | ||
874 | return; | |
875 | } | |
303b6f5d | 876 | } |
8f22cb90 MK |
877 | \f |
878 | ||
a8fd5589 TT |
879 | /* See dwarf2-frame.h. */ |
880 | ||
881 | int | |
882 | dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc, | |
883 | struct dwarf2_per_cu_data *data, | |
884 | int *regnum_out, LONGEST *offset_out, | |
885 | CORE_ADDR *text_offset_out, | |
886 | const gdb_byte **cfa_start_out, | |
887 | const gdb_byte **cfa_end_out) | |
9f6f94ff | 888 | { |
9f6f94ff | 889 | struct dwarf2_fde *fde; |
89b07335 | 890 | dwarf2_per_objfile *per_objfile; |
afe37d6b | 891 | CORE_ADDR pc1 = pc; |
9f6f94ff TT |
892 | |
893 | /* Find the correct FDE. */ | |
89b07335 | 894 | fde = dwarf2_frame_find_fde (&pc1, &per_objfile); |
9f6f94ff TT |
895 | if (fde == NULL) |
896 | error (_("Could not compute CFA; needed to translate this expression")); | |
897 | ||
89b07335 SM |
898 | gdb_assert (per_objfile != nullptr); |
899 | ||
afe37d6b | 900 | dwarf2_frame_state fs (pc1, fde->cie); |
9f6f94ff TT |
901 | |
902 | /* Check for "quirks" - known bugs in producers. */ | |
903 | dwarf2_frame_find_quirks (&fs, fde); | |
904 | ||
905 | /* First decode all the insns in the CIE. */ | |
906 | execute_cfa_program (fde, fde->cie->initial_instructions, | |
89b07335 SM |
907 | fde->cie->end, gdbarch, pc, &fs, |
908 | per_objfile->objfile->text_section_offset ()); | |
9f6f94ff TT |
909 | |
910 | /* Save the initialized register set. */ | |
911 | fs.initial = fs.regs; | |
9f6f94ff TT |
912 | |
913 | /* Then decode the insns in the FDE up to our target PC. */ | |
21982304 | 914 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs, |
89b07335 | 915 | per_objfile->objfile->text_section_offset ()); |
9f6f94ff TT |
916 | |
917 | /* Calculate the CFA. */ | |
918 | switch (fs.regs.cfa_how) | |
919 | { | |
920 | case CFA_REG_OFFSET: | |
921 | { | |
0fde2c53 | 922 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg); |
a8fd5589 TT |
923 | |
924 | *regnum_out = regnum; | |
925 | if (fs.armcc_cfa_offsets_reversed) | |
926 | *offset_out = -fs.regs.cfa_offset; | |
927 | else | |
928 | *offset_out = fs.regs.cfa_offset; | |
929 | return 1; | |
9f6f94ff | 930 | } |
9f6f94ff TT |
931 | |
932 | case CFA_EXP: | |
89b07335 | 933 | *text_offset_out = per_objfile->objfile->text_section_offset (); |
a8fd5589 TT |
934 | *cfa_start_out = fs.regs.cfa_exp; |
935 | *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len; | |
936 | return 0; | |
9f6f94ff TT |
937 | |
938 | default: | |
939 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
940 | } | |
941 | } | |
942 | ||
943 | \f | |
8f22cb90 MK |
944 | struct dwarf2_frame_cache |
945 | { | |
946 | /* DWARF Call Frame Address. */ | |
947 | CORE_ADDR cfa; | |
948 | ||
8fbca658 PA |
949 | /* Set if the return address column was marked as unavailable |
950 | (required non-collected memory or registers to compute). */ | |
951 | int unavailable_retaddr; | |
952 | ||
0228dfb9 DJ |
953 | /* Set if the return address column was marked as undefined. */ |
954 | int undefined_retaddr; | |
955 | ||
8f22cb90 MK |
956 | /* Saved registers, indexed by GDB register number, not by DWARF |
957 | register number. */ | |
958 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
959 | |
960 | /* Return address register. */ | |
961 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
962 | |
963 | /* Target address size in bytes. */ | |
964 | int addr_size; | |
ac56253d | 965 | |
89b07335 SM |
966 | /* The dwarf2_per_objfile from which this frame description came. */ |
967 | dwarf2_per_objfile *per_objfile; | |
111c6489 JK |
968 | |
969 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME | |
970 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
971 | involved. Non-bottom frames of a virtual tail call frames chain use | |
972 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
973 | them. */ | |
974 | void *tailcall_cache; | |
8f22cb90 | 975 | }; |
05cbe71a | 976 | |
b9362cc7 | 977 | static struct dwarf2_frame_cache * |
4a4e5149 | 978 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 979 | { |
4a4e5149 | 980 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
f6efe3f8 | 981 | const int num_regs = gdbarch_num_cooked_regs (gdbarch); |
cfc14b3a | 982 | struct dwarf2_frame_cache *cache; |
cfc14b3a | 983 | struct dwarf2_fde *fde; |
111c6489 | 984 | CORE_ADDR entry_pc; |
111c6489 | 985 | const gdb_byte *instr; |
cfc14b3a MK |
986 | |
987 | if (*this_cache) | |
9a3c8263 | 988 | return (struct dwarf2_frame_cache *) *this_cache; |
cfc14b3a MK |
989 | |
990 | /* Allocate a new cache. */ | |
991 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
992 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 993 | *this_cache = cache; |
cfc14b3a | 994 | |
cfc14b3a MK |
995 | /* Unwind the PC. |
996 | ||
4a4e5149 | 997 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 998 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 999 | its return address. As a result the return address will |
cfc14b3a | 1000 | point at some random instruction, and the CFI for that |
e4e9607c | 1001 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
1002 | this problem by substracting 1 from the return address to get an |
1003 | address in the middle of a presumed call instruction (or the | |
1004 | instruction in the associated delay slot). This should only be | |
1005 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 1006 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 1007 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
1008 | reliable the method is though; there is the potential for the |
1009 | register state pre-call being different to that on return. */ | |
afe37d6b | 1010 | CORE_ADDR pc1 = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1011 | |
1012 | /* Find the correct FDE. */ | |
89b07335 | 1013 | fde = dwarf2_frame_find_fde (&pc1, &cache->per_objfile); |
cfc14b3a | 1014 | gdb_assert (fde != NULL); |
89b07335 | 1015 | gdb_assert (cache->per_objfile != nullptr); |
cfc14b3a | 1016 | |
afe37d6b YQ |
1017 | /* Allocate and initialize the frame state. */ |
1018 | struct dwarf2_frame_state fs (pc1, fde->cie); | |
1019 | ||
ae0d2f24 | 1020 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1021 | |
303b6f5d | 1022 | /* Check for "quirks" - known bugs in producers. */ |
afe37d6b | 1023 | dwarf2_frame_find_quirks (&fs, fde); |
303b6f5d | 1024 | |
cfc14b3a | 1025 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1026 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 | 1027 | fde->cie->end, gdbarch, |
21982304 | 1028 | get_frame_address_in_block (this_frame), &fs, |
89b07335 | 1029 | cache->per_objfile->objfile->text_section_offset ()); |
cfc14b3a MK |
1030 | |
1031 | /* Save the initialized register set. */ | |
afe37d6b | 1032 | fs.initial = fs.regs; |
cfc14b3a | 1033 | |
1aff7173 KB |
1034 | /* Fetching the entry pc for THIS_FRAME won't necessarily result |
1035 | in an address that's within the range of FDE locations. This | |
1036 | is due to the possibility of the function occupying non-contiguous | |
1037 | ranges. */ | |
1009d92f TT |
1038 | LONGEST entry_cfa_sp_offset; |
1039 | int entry_cfa_sp_offset_p = 0; | |
1aff7173 KB |
1040 | if (get_frame_func_if_available (this_frame, &entry_pc) |
1041 | && fde->initial_location <= entry_pc | |
1042 | && entry_pc < fde->initial_location + fde->address_range) | |
111c6489 JK |
1043 | { |
1044 | /* Decode the insns in the FDE up to the entry PC. */ | |
89b07335 SM |
1045 | instr = execute_cfa_program |
1046 | (fde, fde->instructions, fde->end, gdbarch, entry_pc, &fs, | |
1047 | cache->per_objfile->objfile->text_section_offset ()); | |
111c6489 | 1048 | |
afe37d6b YQ |
1049 | if (fs.regs.cfa_how == CFA_REG_OFFSET |
1050 | && (dwarf_reg_to_regnum (gdbarch, fs.regs.cfa_reg) | |
111c6489 JK |
1051 | == gdbarch_sp_regnum (gdbarch))) |
1052 | { | |
1009d92f TT |
1053 | entry_cfa_sp_offset = fs.regs.cfa_offset; |
1054 | entry_cfa_sp_offset_p = 1; | |
111c6489 JK |
1055 | } |
1056 | } | |
1057 | else | |
1058 | instr = fde->instructions; | |
1059 | ||
cfc14b3a | 1060 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1061 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
21982304 | 1062 | get_frame_address_in_block (this_frame), &fs, |
89b07335 | 1063 | cache->per_objfile->objfile->text_section_offset ()); |
cfc14b3a | 1064 | |
a70b8144 | 1065 | try |
cfc14b3a | 1066 | { |
8fbca658 | 1067 | /* Calculate the CFA. */ |
afe37d6b | 1068 | switch (fs.regs.cfa_how) |
8fbca658 PA |
1069 | { |
1070 | case CFA_REG_OFFSET: | |
afe37d6b YQ |
1071 | cache->cfa = read_addr_from_reg (this_frame, fs.regs.cfa_reg); |
1072 | if (fs.armcc_cfa_offsets_reversed) | |
1073 | cache->cfa -= fs.regs.cfa_offset; | |
8fbca658 | 1074 | else |
afe37d6b | 1075 | cache->cfa += fs.regs.cfa_offset; |
8fbca658 PA |
1076 | break; |
1077 | ||
1078 | case CFA_EXP: | |
1079 | cache->cfa = | |
afe37d6b | 1080 | execute_stack_op (fs.regs.cfa_exp, fs.regs.cfa_exp_len, |
89b07335 SM |
1081 | cache->addr_size, this_frame, 0, 0, |
1082 | cache->per_objfile); | |
8fbca658 PA |
1083 | break; |
1084 | ||
1085 | default: | |
1086 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1087 | } | |
1088 | } | |
230d2906 | 1089 | catch (const gdb_exception_error &ex) |
8fbca658 PA |
1090 | { |
1091 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1092 | { | |
1093 | cache->unavailable_retaddr = 1; | |
1094 | return cache; | |
1095 | } | |
cfc14b3a | 1096 | |
eedc3f4f | 1097 | throw; |
cfc14b3a MK |
1098 | } |
1099 | ||
05cbe71a | 1100 | /* Initialize the register state. */ |
3e2c4033 AC |
1101 | { |
1102 | int regnum; | |
e4e9607c | 1103 | |
3e2c4033 | 1104 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1105 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1106 | } |
1107 | ||
1108 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1109 | location information in the cache. Note that we don't skip the |
1110 | return address column; it's perfectly all right for it to | |
0fde2c53 | 1111 | correspond to a real register. */ |
3e2c4033 AC |
1112 | { |
1113 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1114 | |
780942fc | 1115 | for (column = 0; column < fs.regs.reg.size (); column++) |
3e2c4033 | 1116 | { |
3e2c4033 | 1117 | /* Use the GDB register number as the destination index. */ |
0fde2c53 | 1118 | int regnum = dwarf_reg_to_regnum (gdbarch, column); |
3e2c4033 | 1119 | |
0fde2c53 | 1120 | /* Protect against a target returning a bad register. */ |
3e2c4033 AC |
1121 | if (regnum < 0 || regnum >= num_regs) |
1122 | continue; | |
1123 | ||
1124 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1125 | of all debug info registers. If it doesn't, complain (but |
1126 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1127 | unspecified register implies "same value" when CFI (draft |
1128 | 7) specifies nothing at all. Such a register could equally | |
1129 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1130 | isn't sufficient; it only checks that all registers in the |
1131 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1132 | problems when a debug info register falls outside of the |
e4e9607c | 1133 | table. We need a way of iterating through all the valid |
3e2c4033 | 1134 | DWARF2 register numbers. */ |
afe37d6b | 1135 | if (fs.regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1136 | { |
1137 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
b98664d3 | 1138 | complaint (_("\ |
5af949e3 | 1139 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1140 | gdbarch_register_name (gdbarch, regnum), |
afe37d6b | 1141 | paddress (gdbarch, fs.pc)); |
f059bf6f | 1142 | } |
35889917 | 1143 | else |
afe37d6b | 1144 | cache->reg[regnum] = fs.regs.reg[column]; |
3e2c4033 AC |
1145 | } |
1146 | } | |
cfc14b3a | 1147 | |
8d5a9abc MK |
1148 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1149 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1150 | { |
1151 | int regnum; | |
1152 | ||
1153 | for (regnum = 0; regnum < num_regs; regnum++) | |
1154 | { | |
8d5a9abc MK |
1155 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1156 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1157 | { |
780942fc TT |
1158 | const std::vector<struct dwarf2_frame_state_reg> ®s |
1159 | = fs.regs.reg; | |
1160 | ULONGEST retaddr_column = fs.retaddr_column; | |
05cbe71a | 1161 | |
d4f10bf2 | 1162 | /* It seems rather bizarre to specify an "empty" column as |
dda83cd7 SM |
1163 | the return adress column. However, this is exactly |
1164 | what GCC does on some targets. It turns out that GCC | |
1165 | assumes that the return address can be found in the | |
1166 | register corresponding to the return address column. | |
1167 | Incidentally, that's how we should treat a return | |
1168 | address column specifying "same value" too. */ | |
780942fc TT |
1169 | if (fs.retaddr_column < fs.regs.reg.size () |
1170 | && regs[retaddr_column].how != DWARF2_FRAME_REG_UNSPECIFIED | |
1171 | && regs[retaddr_column].how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1172 | { |
1173 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
780942fc | 1174 | cache->reg[regnum] = regs[retaddr_column]; |
8d5a9abc | 1175 | else |
780942fc | 1176 | cache->retaddr_reg = regs[retaddr_column]; |
8d5a9abc | 1177 | } |
35889917 MK |
1178 | else |
1179 | { | |
8d5a9abc MK |
1180 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1181 | { | |
afe37d6b | 1182 | cache->reg[regnum].loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1183 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; |
1184 | } | |
1185 | else | |
1186 | { | |
afe37d6b | 1187 | cache->retaddr_reg.loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1188 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; |
1189 | } | |
35889917 MK |
1190 | } |
1191 | } | |
1192 | } | |
1193 | } | |
cfc14b3a | 1194 | |
780942fc | 1195 | if (fs.retaddr_column < fs.regs.reg.size () |
afe37d6b | 1196 | && fs.regs.reg[fs.retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) |
0228dfb9 DJ |
1197 | cache->undefined_retaddr = 1; |
1198 | ||
1009d92f TT |
1199 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, |
1200 | (entry_cfa_sp_offset_p | |
1201 | ? &entry_cfa_sp_offset : NULL)); | |
1202 | ||
cfc14b3a MK |
1203 | return cache; |
1204 | } | |
1205 | ||
8fbca658 PA |
1206 | static enum unwind_stop_reason |
1207 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1208 | void **this_cache) | |
1209 | { | |
1210 | struct dwarf2_frame_cache *cache | |
1211 | = dwarf2_frame_cache (this_frame, this_cache); | |
1212 | ||
1213 | if (cache->unavailable_retaddr) | |
1214 | return UNWIND_UNAVAILABLE; | |
1215 | ||
1216 | if (cache->undefined_retaddr) | |
1217 | return UNWIND_OUTERMOST; | |
1218 | ||
1219 | return UNWIND_NO_REASON; | |
1220 | } | |
1221 | ||
cfc14b3a | 1222 | static void |
4a4e5149 | 1223 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1224 | struct frame_id *this_id) |
1225 | { | |
1226 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1227 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1228 | |
8fbca658 | 1229 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1230 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1231 | else if (cache->undefined_retaddr) | |
8fbca658 | 1232 | return; |
5ce0145d PA |
1233 | else |
1234 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1235 | } |
1236 | ||
4a4e5149 DJ |
1237 | static struct value * |
1238 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1239 | int regnum) | |
93d42b30 | 1240 | { |
4a4e5149 | 1241 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1242 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1243 | dwarf2_frame_cache (this_frame, this_cache); |
1244 | CORE_ADDR addr; | |
1245 | int realnum; | |
cfc14b3a | 1246 | |
111c6489 JK |
1247 | /* Non-bottom frames of a virtual tail call frames chain use |
1248 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1249 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1250 | unwind the register, tail call frames are assumed to have the register set | |
1251 | of the top caller. */ | |
1252 | if (cache->tailcall_cache) | |
1253 | { | |
1254 | struct value *val; | |
1255 | ||
1256 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1257 | &cache->tailcall_cache, | |
1258 | regnum); | |
1259 | if (val) | |
1260 | return val; | |
1261 | } | |
1262 | ||
cfc14b3a MK |
1263 | switch (cache->reg[regnum].how) |
1264 | { | |
05cbe71a | 1265 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1266 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1267 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1268 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1269 | |
05cbe71a | 1270 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1271 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1272 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1273 | |
05cbe71a | 1274 | case DWARF2_FRAME_REG_SAVED_REG: |
0fde2c53 DE |
1275 | realnum = dwarf_reg_to_regnum_or_error |
1276 | (gdbarch, cache->reg[regnum].loc.reg); | |
4a4e5149 | 1277 | return frame_unwind_got_register (this_frame, regnum, realnum); |
cfc14b3a | 1278 | |
05cbe71a | 1279 | case DWARF2_FRAME_REG_SAVED_EXP: |
b348037f YQ |
1280 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1281 | cache->reg[regnum].loc.exp.len, | |
89b07335 SM |
1282 | cache->addr_size, |
1283 | this_frame, cache->cfa, 1, | |
1284 | cache->per_objfile); | |
4a4e5149 | 1285 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1286 | |
46ea248b | 1287 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1288 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1289 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1290 | |
1291 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
b348037f YQ |
1292 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1293 | cache->reg[regnum].loc.exp.len, | |
89b07335 SM |
1294 | cache->addr_size, |
1295 | this_frame, cache->cfa, 1, | |
1296 | cache->per_objfile); | |
4a4e5149 | 1297 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1298 | |
05cbe71a | 1299 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1300 | /* GCC, in its infinite wisdom decided to not provide unwind |
1301 | information for registers that are "same value". Since | |
1302 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1303 | registers are actually undefined (which is different to CFI | |
1304 | "undefined"). Code above issues a complaint about this. | |
1305 | Here just fudge the books, assume GCC, and that the value is | |
1306 | more inner on the stack. */ | |
4a4e5149 | 1307 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1308 | |
05cbe71a | 1309 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1310 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1311 | |
05cbe71a | 1312 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1313 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1314 | |
ea7963f0 | 1315 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1316 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1317 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1318 | |
8d5a9abc | 1319 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 | 1320 | addr = cache->reg[regnum].loc.offset; |
0fde2c53 | 1321 | regnum = dwarf_reg_to_regnum_or_error |
4a4e5149 DJ |
1322 | (gdbarch, cache->retaddr_reg.loc.reg); |
1323 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1324 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1325 | |
b39cc962 DJ |
1326 | case DWARF2_FRAME_REG_FN: |
1327 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1328 | ||
cfc14b3a | 1329 | default: |
e2e0b3e5 | 1330 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1331 | } |
1332 | } | |
1333 | ||
111c6489 JK |
1334 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1335 | call frames chain. */ | |
1336 | ||
1337 | static void | |
1338 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1339 | { | |
1340 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1341 | ||
1342 | if (cache->tailcall_cache) | |
1343 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1344 | } | |
1345 | ||
4a4e5149 DJ |
1346 | static int |
1347 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1348 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1349 | { |
3c3bb058 AB |
1350 | if (!dwarf2_frame_unwinders_enabled_p) |
1351 | return 0; | |
1352 | ||
30baf67b | 1353 | /* Grab an address that is guaranteed to reside somewhere within the |
4a4e5149 | 1354 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1355 | end up returning something past the end of this function's body. |
1356 | If the frame we're sniffing for is a signal frame whose start | |
1357 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1358 | extend one byte before its start address or we could potentially |
1359 | select the FDE of the previous function. */ | |
1360 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1361 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1362 | |
56c987f6 | 1363 | if (!fde) |
4a4e5149 | 1364 | return 0; |
3ed09a32 DJ |
1365 | |
1366 | /* On some targets, signal trampolines may have unwind information. | |
1367 | We need to recognize them so that we set the frame type | |
1368 | correctly. */ | |
1369 | ||
56c987f6 | 1370 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1371 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1372 | this_frame)) | |
1373 | return self->type == SIGTRAMP_FRAME; | |
1374 | ||
111c6489 JK |
1375 | if (self->type != NORMAL_FRAME) |
1376 | return 0; | |
1377 | ||
111c6489 | 1378 | return 1; |
4a4e5149 DJ |
1379 | } |
1380 | ||
1381 | static const struct frame_unwind dwarf2_frame_unwind = | |
1382 | { | |
a154d838 | 1383 | "dwarf2", |
4a4e5149 | 1384 | NORMAL_FRAME, |
8fbca658 | 1385 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1386 | dwarf2_frame_this_id, |
1387 | dwarf2_frame_prev_register, | |
1388 | NULL, | |
111c6489 JK |
1389 | dwarf2_frame_sniffer, |
1390 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1391 | }; |
1392 | ||
1393 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1394 | { | |
a154d838 | 1395 | "dwarf2 signal", |
4a4e5149 | 1396 | SIGTRAMP_FRAME, |
8fbca658 | 1397 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1398 | dwarf2_frame_this_id, |
1399 | dwarf2_frame_prev_register, | |
1400 | NULL, | |
111c6489 JK |
1401 | dwarf2_frame_sniffer, |
1402 | ||
1403 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1404 | NULL | |
4a4e5149 | 1405 | }; |
cfc14b3a | 1406 | |
4a4e5149 DJ |
1407 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1408 | ||
1409 | void | |
1410 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1411 | { | |
1412 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); | |
1413 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1414 | } |
1415 | \f | |
1416 | ||
1417 | /* There is no explicitly defined relationship between the CFA and the | |
1418 | location of frame's local variables and arguments/parameters. | |
1419 | Therefore, frame base methods on this page should probably only be | |
1420 | used as a last resort, just to avoid printing total garbage as a | |
1421 | response to the "info frame" command. */ | |
1422 | ||
1423 | static CORE_ADDR | |
4a4e5149 | 1424 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1425 | { |
1426 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1427 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1428 | |
1429 | return cache->cfa; | |
1430 | } | |
1431 | ||
1432 | static const struct frame_base dwarf2_frame_base = | |
1433 | { | |
1434 | &dwarf2_frame_unwind, | |
1435 | dwarf2_frame_base_address, | |
1436 | dwarf2_frame_base_address, | |
1437 | dwarf2_frame_base_address | |
1438 | }; | |
1439 | ||
1440 | const struct frame_base * | |
4a4e5149 | 1441 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1442 | { |
4a4e5149 | 1443 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1444 | |
ac56253d | 1445 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1446 | return &dwarf2_frame_base; |
1447 | ||
1448 | return NULL; | |
1449 | } | |
e7802207 TT |
1450 | |
1451 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1452 | the DWARF unwinder. This is used to implement | |
1453 | DW_OP_call_frame_cfa. */ | |
1454 | ||
1455 | CORE_ADDR | |
1456 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1457 | { | |
0b722aec MM |
1458 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1459 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1460 | throw_error (NOT_AVAILABLE_ERROR, | |
1461 | _("cfa not available for record btrace target")); | |
1462 | ||
e7802207 TT |
1463 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1464 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1465 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1466 | throw_error (NOT_AVAILABLE_ERROR, | |
dda83cd7 SM |
1467 | _("can't compute CFA for this frame: " |
1468 | "required registers or memory are unavailable")); | |
14aba1ac JB |
1469 | |
1470 | if (get_frame_id (this_frame).stack_status != FID_STACK_VALID) | |
1471 | throw_error (NOT_AVAILABLE_ERROR, | |
dda83cd7 SM |
1472 | _("can't compute CFA for this frame: " |
1473 | "frame base not available")); | |
14aba1ac | 1474 | |
e7802207 TT |
1475 | return get_frame_base (this_frame); |
1476 | } | |
cfc14b3a | 1477 | \f |
3d4560f7 TT |
1478 | /* We store the frame data on the BFD. This is only done if it is |
1479 | independent of the address space and so can be shared. */ | |
1480 | static const struct bfd_key<comp_unit> dwarf2_frame_bfd_data; | |
1481 | ||
1482 | /* If any BFD sections require relocations (note; really should be if | |
1483 | any debug info requires relocations), then we store the frame data | |
1484 | on the objfile instead, and do not share it. */ | |
1485 | const struct objfile_key<comp_unit> dwarf2_frame_objfile_data; | |
cfc14b3a MK |
1486 | \f |
1487 | ||
1488 | /* Pointer encoding helper functions. */ | |
1489 | ||
1490 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1491 | technical reasons, it encodes addresses in its FDE's in a different | |
1492 | way. Several "pointer encodings" are supported. The encoding | |
1493 | that's used for a particular FDE is determined by the 'R' | |
1494 | augmentation in the associated CIE. The argument of this | |
1495 | augmentation is a single byte. | |
1496 | ||
1497 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1498 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1499 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1500 | address should be interpreted (absolute, relative to the current | |
1501 | position in the FDE, ...). Bit 7, indicates that the address | |
1502 | should be dereferenced. */ | |
1503 | ||
852483bc | 1504 | static gdb_byte |
cfc14b3a MK |
1505 | encoding_for_size (unsigned int size) |
1506 | { | |
1507 | switch (size) | |
1508 | { | |
1509 | case 2: | |
1510 | return DW_EH_PE_udata2; | |
1511 | case 4: | |
1512 | return DW_EH_PE_udata4; | |
1513 | case 8: | |
1514 | return DW_EH_PE_udata8; | |
1515 | default: | |
e2e0b3e5 | 1516 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1517 | } |
1518 | } | |
1519 | ||
cfc14b3a | 1520 | static CORE_ADDR |
852483bc | 1521 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1522 | int ptr_len, const gdb_byte *buf, |
1523 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1524 | CORE_ADDR func_base) |
cfc14b3a | 1525 | { |
68f6cf99 | 1526 | ptrdiff_t offset; |
cfc14b3a MK |
1527 | CORE_ADDR base; |
1528 | ||
1529 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1530 | FDE's. */ | |
1531 | if (encoding & DW_EH_PE_indirect) | |
1532 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1533 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1534 | |
68f6cf99 MK |
1535 | *bytes_read_ptr = 0; |
1536 | ||
cfc14b3a MK |
1537 | switch (encoding & 0x70) |
1538 | { | |
1539 | case DW_EH_PE_absptr: | |
1540 | base = 0; | |
1541 | break; | |
1542 | case DW_EH_PE_pcrel: | |
fd361982 | 1543 | base = bfd_section_vma (unit->dwarf_frame_section); |
852483bc | 1544 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1545 | break; |
0912c7f2 MK |
1546 | case DW_EH_PE_datarel: |
1547 | base = unit->dbase; | |
1548 | break; | |
0fd85043 CV |
1549 | case DW_EH_PE_textrel: |
1550 | base = unit->tbase; | |
1551 | break; | |
03ac2a74 | 1552 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1553 | base = func_base; |
03ac2a74 | 1554 | break; |
68f6cf99 MK |
1555 | case DW_EH_PE_aligned: |
1556 | base = 0; | |
852483bc | 1557 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1558 | if ((offset % ptr_len) != 0) |
1559 | { | |
1560 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1561 | buf += *bytes_read_ptr; | |
1562 | } | |
1563 | break; | |
cfc14b3a | 1564 | default: |
3e43a32a MS |
1565 | internal_error (__FILE__, __LINE__, |
1566 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1567 | } |
1568 | ||
b04de778 | 1569 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1570 | { |
1571 | encoding |= encoding_for_size (ptr_len); | |
1572 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1573 | encoding |= DW_EH_PE_signed; | |
1574 | } | |
cfc14b3a MK |
1575 | |
1576 | switch (encoding & 0x0f) | |
1577 | { | |
a81b10ae MK |
1578 | case DW_EH_PE_uleb128: |
1579 | { | |
9fccedf7 | 1580 | uint64_t value; |
0d45f56e | 1581 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1582 | |
f664829e | 1583 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1584 | return base + value; |
1585 | } | |
cfc14b3a | 1586 | case DW_EH_PE_udata2: |
68f6cf99 | 1587 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1588 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1589 | case DW_EH_PE_udata4: | |
68f6cf99 | 1590 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1591 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1592 | case DW_EH_PE_udata8: | |
68f6cf99 | 1593 | *bytes_read_ptr += 8; |
cfc14b3a | 1594 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1595 | case DW_EH_PE_sleb128: |
1596 | { | |
9fccedf7 | 1597 | int64_t value; |
0d45f56e | 1598 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1599 | |
f664829e | 1600 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1601 | return base + value; |
1602 | } | |
cfc14b3a | 1603 | case DW_EH_PE_sdata2: |
68f6cf99 | 1604 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1605 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1606 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1607 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1608 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1609 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1610 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1611 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1612 | default: | |
3e43a32a MS |
1613 | internal_error (__FILE__, __LINE__, |
1614 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1615 | } |
1616 | } | |
1617 | \f | |
1618 | ||
b01c8410 PP |
1619 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ |
1620 | static struct dwarf2_cie * | |
93878f47 | 1621 | find_cie (const dwarf2_cie_table &cie_table, ULONGEST cie_pointer) |
b01c8410 | 1622 | { |
93878f47 TT |
1623 | auto iter = cie_table.find (cie_pointer); |
1624 | if (iter != cie_table.end ()) | |
1625 | return iter->second; | |
cfc14b3a MK |
1626 | return NULL; |
1627 | } | |
1628 | ||
35e65c49 CB |
1629 | static inline int |
1630 | bsearch_fde_cmp (const dwarf2_fde *fde, CORE_ADDR seek_pc) | |
b01c8410 | 1631 | { |
35e65c49 | 1632 | if (fde->initial_location + fde->address_range <= seek_pc) |
b01c8410 | 1633 | return -1; |
35e65c49 | 1634 | if (fde->initial_location <= seek_pc) |
b01c8410 PP |
1635 | return 0; |
1636 | return 1; | |
cfc14b3a MK |
1637 | } |
1638 | ||
3d4560f7 TT |
1639 | /* Find an existing comp_unit for an objfile, if any. */ |
1640 | ||
1641 | static comp_unit * | |
1642 | find_comp_unit (struct objfile *objfile) | |
1643 | { | |
1644 | bfd *abfd = objfile->obfd; | |
1645 | if (gdb_bfd_requires_relocations (abfd)) | |
0bc2e38d SM |
1646 | return dwarf2_frame_objfile_data.get (objfile); |
1647 | ||
1648 | return dwarf2_frame_bfd_data.get (abfd); | |
3d4560f7 TT |
1649 | } |
1650 | ||
1651 | /* Store the comp_unit on OBJFILE, or the corresponding BFD, as | |
1652 | appropriate. */ | |
1653 | ||
1654 | static void | |
1655 | set_comp_unit (struct objfile *objfile, struct comp_unit *unit) | |
1656 | { | |
1657 | bfd *abfd = objfile->obfd; | |
1658 | if (gdb_bfd_requires_relocations (abfd)) | |
0bc2e38d SM |
1659 | return dwarf2_frame_objfile_data.set (objfile, unit); |
1660 | ||
1661 | return dwarf2_frame_bfd_data.set (abfd, unit); | |
3d4560f7 TT |
1662 | } |
1663 | ||
cfc14b3a | 1664 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the |
85102364 | 1665 | initial location associated with it into *PC. */ |
cfc14b3a MK |
1666 | |
1667 | static struct dwarf2_fde * | |
89b07335 | 1668 | dwarf2_frame_find_fde (CORE_ADDR *pc, dwarf2_per_objfile **out_per_objfile) |
cfc14b3a | 1669 | { |
2030c079 | 1670 | for (objfile *objfile : current_program_space->objfiles ()) |
cfc14b3a | 1671 | { |
cfc14b3a | 1672 | CORE_ADDR offset; |
b01c8410 | 1673 | CORE_ADDR seek_pc; |
cfc14b3a | 1674 | |
3d4560f7 | 1675 | comp_unit *unit = find_comp_unit (objfile); |
a7a3ae5c | 1676 | if (unit == NULL) |
be391dca TT |
1677 | { |
1678 | dwarf2_build_frame_info (objfile); | |
3d4560f7 | 1679 | unit = find_comp_unit (objfile); |
be391dca | 1680 | } |
a7a3ae5c | 1681 | gdb_assert (unit != NULL); |
be391dca | 1682 | |
a7a3ae5c | 1683 | dwarf2_fde_table *fde_table = &unit->fde_table; |
a9d65418 | 1684 | if (fde_table->empty ()) |
4ae9ee8e DJ |
1685 | continue; |
1686 | ||
6a053cb1 | 1687 | gdb_assert (!objfile->section_offsets.empty ()); |
b3b3bada | 1688 | offset = objfile->text_section_offset (); |
4ae9ee8e | 1689 | |
a9d65418 TT |
1690 | gdb_assert (!fde_table->empty ()); |
1691 | if (*pc < offset + (*fde_table)[0]->initial_location) | |
dda83cd7 | 1692 | continue; |
b01c8410 PP |
1693 | |
1694 | seek_pc = *pc - offset; | |
a9d65418 TT |
1695 | auto it = gdb::binary_search (fde_table->begin (), fde_table->end (), |
1696 | seek_pc, bsearch_fde_cmp); | |
1697 | if (it != fde_table->end ()) | |
dda83cd7 SM |
1698 | { |
1699 | *pc = (*it)->initial_location + offset; | |
89b07335 SM |
1700 | if (out_per_objfile != nullptr) |
1701 | *out_per_objfile = get_dwarf2_per_objfile (objfile); | |
1702 | ||
dda83cd7 SM |
1703 | return *it; |
1704 | } | |
cfc14b3a | 1705 | } |
cfc14b3a MK |
1706 | return NULL; |
1707 | } | |
1708 | ||
a9d65418 | 1709 | /* Add FDE to FDE_TABLE. */ |
cfc14b3a | 1710 | static void |
a9d65418 | 1711 | add_fde (dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1712 | { |
b01c8410 PP |
1713 | if (fde->address_range == 0) |
1714 | /* Discard useless FDEs. */ | |
1715 | return; | |
1716 | ||
a9d65418 | 1717 | fde_table->push_back (fde); |
cfc14b3a MK |
1718 | } |
1719 | ||
cfc14b3a | 1720 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1721 | |
8bd90839 FM |
1722 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1723 | or any of them. */ | |
1724 | ||
1725 | enum eh_frame_type | |
1726 | { | |
1727 | EH_CIE_TYPE_ID = 1 << 0, | |
1728 | EH_FDE_TYPE_ID = 1 << 1, | |
1729 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1730 | }; | |
1731 | ||
4debb237 TT |
1732 | static const gdb_byte *decode_frame_entry (struct gdbarch *gdbarch, |
1733 | struct comp_unit *unit, | |
f664829e DE |
1734 | const gdb_byte *start, |
1735 | int eh_frame_p, | |
93878f47 | 1736 | dwarf2_cie_table &cie_table, |
a9d65418 | 1737 | dwarf2_fde_table *fde_table, |
f664829e | 1738 | enum eh_frame_type entry_type); |
8bd90839 FM |
1739 | |
1740 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1741 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1742 | |
f664829e | 1743 | static const gdb_byte * |
4debb237 TT |
1744 | decode_frame_entry_1 (struct gdbarch *gdbarch, |
1745 | struct comp_unit *unit, const gdb_byte *start, | |
f664829e | 1746 | int eh_frame_p, |
dda83cd7 SM |
1747 | dwarf2_cie_table &cie_table, |
1748 | dwarf2_fde_table *fde_table, | |
1749 | enum eh_frame_type entry_type) | |
cfc14b3a | 1750 | { |
f664829e | 1751 | const gdb_byte *buf, *end; |
723adb65 | 1752 | ULONGEST length; |
cfc14b3a | 1753 | unsigned int bytes_read; |
6896c0c7 RH |
1754 | int dwarf64_p; |
1755 | ULONGEST cie_id; | |
cfc14b3a | 1756 | ULONGEST cie_pointer; |
9fccedf7 DE |
1757 | int64_t sleb128; |
1758 | uint64_t uleb128; | |
cfc14b3a | 1759 | |
6896c0c7 | 1760 | buf = start; |
4075cb26 | 1761 | length = read_initial_length (unit->abfd, buf, &bytes_read, false); |
cfc14b3a | 1762 | buf += bytes_read; |
723adb65 | 1763 | end = buf + (size_t) length; |
6896c0c7 | 1764 | |
cfc14b3a MK |
1765 | if (length == 0) |
1766 | return end; | |
1767 | ||
723adb65 SL |
1768 | /* Are we still within the section? */ |
1769 | if (end <= buf || end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1770 | return NULL; | |
1771 | ||
6896c0c7 RH |
1772 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1773 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1774 | |
6896c0c7 | 1775 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1776 | if (eh_frame_p) |
1777 | cie_id = 0; | |
1778 | else if (dwarf64_p) | |
1779 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1780 | else |
1781 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1782 | |
1783 | if (dwarf64_p) | |
1784 | { | |
1785 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1786 | buf += 8; | |
1787 | } | |
1788 | else | |
1789 | { | |
1790 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1791 | buf += 4; | |
1792 | } | |
1793 | ||
1794 | if (cie_pointer == cie_id) | |
1795 | { | |
1796 | /* This is a CIE. */ | |
1797 | struct dwarf2_cie *cie; | |
1798 | char *augmentation; | |
28ba0b33 | 1799 | unsigned int cie_version; |
cfc14b3a | 1800 | |
8bd90839 FM |
1801 | /* Check that a CIE was expected. */ |
1802 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1803 | error (_("Found a CIE when not expecting it.")); | |
1804 | ||
cfc14b3a MK |
1805 | /* Record the offset into the .debug_frame section of this CIE. */ |
1806 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1807 | ||
1808 | /* Check whether we've already read it. */ | |
b01c8410 | 1809 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1810 | return end; |
1811 | ||
0d404d44 | 1812 | cie = XOBNEW (&unit->obstack, struct dwarf2_cie); |
cfc14b3a MK |
1813 | cie->initial_instructions = NULL; |
1814 | cie->cie_pointer = cie_pointer; | |
1815 | ||
1816 | /* The encoding for FDE's in a normal .debug_frame section | |
dda83cd7 | 1817 | depends on the target address size. */ |
32b05c07 | 1818 | cie->encoding = DW_EH_PE_absptr; |
cfc14b3a | 1819 | |
56c987f6 AO |
1820 | /* We'll determine the final value later, but we need to |
1821 | initialize it conservatively. */ | |
1822 | cie->signal_frame = 0; | |
1823 | ||
cfc14b3a | 1824 | /* Check version number. */ |
28ba0b33 | 1825 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1826 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1827 | return NULL; |
303b6f5d | 1828 | cie->version = cie_version; |
cfc14b3a MK |
1829 | buf += 1; |
1830 | ||
1831 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1832 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1833 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1834 | |
303b6f5d DJ |
1835 | /* Ignore armcc augmentations. We only use them for quirks, |
1836 | and that doesn't happen until later. */ | |
61012eef | 1837 | if (startswith (augmentation, "armcc")) |
303b6f5d DJ |
1838 | augmentation += strlen (augmentation); |
1839 | ||
cfc14b3a | 1840 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
dda83cd7 SM |
1841 | following the augmentation string, so it must be handled |
1842 | first. */ | |
cfc14b3a MK |
1843 | if (augmentation[0] == 'e' && augmentation[1] == 'h') |
1844 | { | |
1845 | /* Skip. */ | |
5e2b427d | 1846 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1847 | augmentation += 2; |
1848 | } | |
1849 | ||
2dc7f7b3 TT |
1850 | if (cie->version >= 4) |
1851 | { | |
1852 | /* FIXME: check that this is the same as from the CU header. */ | |
1853 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1854 | ++buf; | |
1855 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1856 | ++buf; | |
1857 | } | |
1858 | else | |
1859 | { | |
8da614df | 1860 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1861 | cie->segment_size = 0; |
1862 | } | |
8da614df CV |
1863 | /* Address values in .eh_frame sections are defined to have the |
1864 | target's pointer size. Watchout: This breaks frame info for | |
1865 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1866 | section exists as well. */ |
8da614df CV |
1867 | if (eh_frame_p) |
1868 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1869 | else | |
1870 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1871 | |
f664829e DE |
1872 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1873 | if (buf == NULL) | |
1874 | return NULL; | |
1875 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1876 | |
f664829e DE |
1877 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1878 | if (buf == NULL) | |
1879 | return NULL; | |
1880 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1881 | |
28ba0b33 PB |
1882 | if (cie_version == 1) |
1883 | { | |
1884 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1885 | ++buf; |
28ba0b33 PB |
1886 | } |
1887 | else | |
f664829e DE |
1888 | { |
1889 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1890 | if (buf == NULL) | |
1891 | return NULL; | |
1892 | cie->return_address_register = uleb128; | |
1893 | } | |
1894 | ||
4fc771b8 | 1895 | cie->return_address_register |
5e2b427d | 1896 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1897 | cie->return_address_register, |
1898 | eh_frame_p); | |
4bf8967c | 1899 | |
7131cb6e RH |
1900 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1901 | if (cie->saw_z_augmentation) | |
cfc14b3a | 1902 | { |
b926417a | 1903 | uint64_t uleb_length; |
cfc14b3a | 1904 | |
b926417a | 1905 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e | 1906 | if (buf == NULL) |
6896c0c7 | 1907 | return NULL; |
b926417a | 1908 | cie->initial_instructions = buf + uleb_length; |
cfc14b3a MK |
1909 | augmentation++; |
1910 | } | |
1911 | ||
1912 | while (*augmentation) | |
1913 | { | |
1914 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1915 | if (*augmentation == 'L') | |
1916 | { | |
1917 | /* Skip. */ | |
1918 | buf++; | |
1919 | augmentation++; | |
1920 | } | |
1921 | ||
1922 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1923 | else if (*augmentation == 'R') | |
1924 | { | |
1925 | cie->encoding = *buf++; | |
1926 | augmentation++; | |
1927 | } | |
1928 | ||
1929 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1930 | else if (*augmentation == 'P') | |
1931 | { | |
1234d960 | 1932 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1933 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1934 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1935 | buf, &bytes_read, 0); |
f724bf08 | 1936 | buf += bytes_read; |
cfc14b3a MK |
1937 | augmentation++; |
1938 | } | |
1939 | ||
56c987f6 AO |
1940 | /* "S" indicates a signal frame, such that the return |
1941 | address must not be decremented to locate the call frame | |
1942 | info for the previous frame; it might even be the first | |
1943 | instruction of a function, so decrementing it would take | |
1944 | us to a different function. */ | |
1945 | else if (*augmentation == 'S') | |
1946 | { | |
1947 | cie->signal_frame = 1; | |
1948 | augmentation++; | |
1949 | } | |
1950 | ||
3e9a2e52 DJ |
1951 | /* Otherwise we have an unknown augmentation. Assume that either |
1952 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1953 | else |
1954 | { | |
3e9a2e52 DJ |
1955 | if (cie->initial_instructions) |
1956 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1957 | break; |
1958 | } | |
1959 | } | |
1960 | ||
1961 | cie->initial_instructions = buf; | |
1962 | cie->end = end; | |
b01c8410 | 1963 | cie->unit = unit; |
cfc14b3a | 1964 | |
93878f47 | 1965 | cie_table[cie->cie_pointer] = cie; |
cfc14b3a MK |
1966 | } |
1967 | else | |
1968 | { | |
1969 | /* This is a FDE. */ | |
1970 | struct dwarf2_fde *fde; | |
3e29f34a | 1971 | CORE_ADDR addr; |
cfc14b3a | 1972 | |
8bd90839 FM |
1973 | /* Check that an FDE was expected. */ |
1974 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
1975 | error (_("Found an FDE when not expecting it.")); | |
1976 | ||
6896c0c7 RH |
1977 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1978 | address within the FDE where the CIE pointer is stored and the | |
1979 | address of the CIE. Convert it to an offset into the .eh_frame | |
1980 | section. */ | |
cfc14b3a MK |
1981 | if (eh_frame_p) |
1982 | { | |
cfc14b3a MK |
1983 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1984 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1985 | } | |
1986 | ||
6896c0c7 RH |
1987 | /* In either case, validate the result is still within the section. */ |
1988 | if (cie_pointer >= unit->dwarf_frame_size) | |
1989 | return NULL; | |
1990 | ||
0d404d44 | 1991 | fde = XOBNEW (&unit->obstack, struct dwarf2_fde); |
b01c8410 | 1992 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
1993 | if (fde->cie == NULL) |
1994 | { | |
4debb237 TT |
1995 | decode_frame_entry (gdbarch, unit, |
1996 | unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
1997 | eh_frame_p, cie_table, fde_table, |
1998 | EH_CIE_TYPE_ID); | |
b01c8410 | 1999 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2000 | } |
2001 | ||
2002 | gdb_assert (fde->cie != NULL); | |
2003 | ||
3e29f34a MR |
2004 | addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
2005 | buf, &bytes_read, 0); | |
2006 | fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); | |
cfc14b3a MK |
2007 | buf += bytes_read; |
2008 | ||
2009 | fde->address_range = | |
ae0d2f24 | 2010 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 2011 | fde->cie->ptr_size, buf, &bytes_read, 0); |
3e29f34a MR |
2012 | addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); |
2013 | fde->address_range = addr - fde->initial_location; | |
cfc14b3a MK |
2014 | buf += bytes_read; |
2015 | ||
7131cb6e RH |
2016 | /* A 'z' augmentation in the CIE implies the presence of an |
2017 | augmentation field in the FDE as well. The only thing known | |
2018 | to be in here at present is the LSDA entry for EH. So we | |
2019 | can skip the whole thing. */ | |
2020 | if (fde->cie->saw_z_augmentation) | |
2021 | { | |
b926417a | 2022 | uint64_t uleb_length; |
7131cb6e | 2023 | |
b926417a | 2024 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e DE |
2025 | if (buf == NULL) |
2026 | return NULL; | |
b926417a | 2027 | buf += uleb_length; |
6896c0c7 RH |
2028 | if (buf > end) |
2029 | return NULL; | |
7131cb6e RH |
2030 | } |
2031 | ||
cfc14b3a MK |
2032 | fde->instructions = buf; |
2033 | fde->end = end; | |
2034 | ||
4bf8967c AS |
2035 | fde->eh_frame_p = eh_frame_p; |
2036 | ||
b01c8410 | 2037 | add_fde (fde_table, fde); |
cfc14b3a MK |
2038 | } |
2039 | ||
2040 | return end; | |
2041 | } | |
6896c0c7 | 2042 | |
8bd90839 FM |
2043 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2044 | expect an FDE or a CIE. */ | |
2045 | ||
f664829e | 2046 | static const gdb_byte * |
4debb237 TT |
2047 | decode_frame_entry (struct gdbarch *gdbarch, |
2048 | struct comp_unit *unit, const gdb_byte *start, | |
f664829e | 2049 | int eh_frame_p, |
93878f47 | 2050 | dwarf2_cie_table &cie_table, |
dda83cd7 SM |
2051 | dwarf2_fde_table *fde_table, |
2052 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2053 | { |
2054 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2055 | const gdb_byte *ret; |
6896c0c7 RH |
2056 | ptrdiff_t start_offset; |
2057 | ||
2058 | while (1) | |
2059 | { | |
4debb237 | 2060 | ret = decode_frame_entry_1 (gdbarch, unit, start, eh_frame_p, |
8bd90839 | 2061 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2062 | if (ret != NULL) |
2063 | break; | |
2064 | ||
2065 | /* We have corrupt input data of some form. */ | |
2066 | ||
2067 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2068 | and mismatches wrt padding and alignment of debug sections. */ | |
2069 | /* Note that there is no requirement in the standard for any | |
2070 | alignment at all in the frame unwind sections. Testing for | |
2071 | alignment before trying to interpret data would be incorrect. | |
2072 | ||
2073 | However, GCC traditionally arranged for frame sections to be | |
2074 | sized such that the FDE length and CIE fields happen to be | |
2075 | aligned (in theory, for performance). This, unfortunately, | |
2076 | was done with .align directives, which had the side effect of | |
2077 | forcing the section to be aligned by the linker. | |
2078 | ||
2079 | This becomes a problem when you have some other producer that | |
2080 | creates frame sections that are not as strictly aligned. That | |
2081 | produces a hole in the frame info that gets filled by the | |
2082 | linker with zeros. | |
2083 | ||
2084 | The GCC behaviour is arguably a bug, but it's effectively now | |
2085 | part of the ABI, so we're now stuck with it, at least at the | |
2086 | object file level. A smart linker may decide, in the process | |
2087 | of compressing duplicate CIE information, that it can rewrite | |
2088 | the entire output section without this extra padding. */ | |
2089 | ||
2090 | start_offset = start - unit->dwarf_frame_buffer; | |
2091 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2092 | { | |
2093 | start += 4 - (start_offset & 3); | |
2094 | workaround = ALIGN4; | |
2095 | continue; | |
2096 | } | |
2097 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2098 | { | |
2099 | start += 8 - (start_offset & 7); | |
2100 | workaround = ALIGN8; | |
2101 | continue; | |
2102 | } | |
2103 | ||
2104 | /* Nothing left to try. Arrange to return as if we've consumed | |
2105 | the entire input section. Hopefully we'll get valid info from | |
2106 | the other of .debug_frame/.eh_frame. */ | |
2107 | workaround = FAIL; | |
2108 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2109 | break; | |
2110 | } | |
2111 | ||
2112 | switch (workaround) | |
2113 | { | |
2114 | case NONE: | |
2115 | break; | |
2116 | ||
2117 | case ALIGN4: | |
b98664d3 | 2118 | complaint (_("\ |
3e43a32a | 2119 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
c7e97679 AM |
2120 | bfd_get_filename (unit->dwarf_frame_section->owner), |
2121 | bfd_section_name (unit->dwarf_frame_section)); | |
6896c0c7 RH |
2122 | break; |
2123 | ||
2124 | case ALIGN8: | |
b98664d3 | 2125 | complaint (_("\ |
3e43a32a | 2126 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
c7e97679 AM |
2127 | bfd_get_filename (unit->dwarf_frame_section->owner), |
2128 | bfd_section_name (unit->dwarf_frame_section)); | |
6896c0c7 RH |
2129 | break; |
2130 | ||
2131 | default: | |
b98664d3 | 2132 | complaint (_("Corrupt data in %s:%s"), |
c7e97679 AM |
2133 | bfd_get_filename (unit->dwarf_frame_section->owner), |
2134 | bfd_section_name (unit->dwarf_frame_section)); | |
6896c0c7 RH |
2135 | break; |
2136 | } | |
2137 | ||
2138 | return ret; | |
2139 | } | |
cfc14b3a | 2140 | \f |
39ef2f62 CB |
2141 | static bool |
2142 | fde_is_less_than (const dwarf2_fde *aa, const dwarf2_fde *bb) | |
b01c8410 | 2143 | { |
b01c8410 | 2144 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2145 | { |
2146 | if (aa->address_range != bb->address_range | |
dda83cd7 SM |
2147 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) |
2148 | /* Linker bug, e.g. gold/10400. | |
2149 | Work around it by keeping stable sort order. */ | |
2150 | return aa < bb; | |
e5af178f | 2151 | else |
dda83cd7 SM |
2152 | /* Put eh_frame entries after debug_frame ones. */ |
2153 | return aa->eh_frame_p < bb->eh_frame_p; | |
e5af178f | 2154 | } |
b01c8410 | 2155 | |
39ef2f62 | 2156 | return aa->initial_location < bb->initial_location; |
b01c8410 PP |
2157 | } |
2158 | ||
cfc14b3a MK |
2159 | void |
2160 | dwarf2_build_frame_info (struct objfile *objfile) | |
2161 | { | |
f664829e | 2162 | const gdb_byte *frame_ptr; |
93878f47 | 2163 | dwarf2_cie_table cie_table; |
a9d65418 | 2164 | dwarf2_fde_table fde_table; |
cfc14b3a | 2165 | |
08feed99 | 2166 | struct gdbarch *gdbarch = objfile->arch (); |
4debb237 | 2167 | |
cfc14b3a | 2168 | /* Build a minimal decoding of the DWARF2 compilation unit. */ |
a7a3ae5c | 2169 | std::unique_ptr<comp_unit> unit (new comp_unit (objfile)); |
cfc14b3a | 2170 | |
d40102a1 | 2171 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2172 | { |
d40102a1 | 2173 | /* Do not read .eh_frame from separate file as they must be also |
dda83cd7 | 2174 | present in the main file. */ |
d40102a1 | 2175 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, |
dda83cd7 SM |
2176 | &unit->dwarf_frame_section, |
2177 | &unit->dwarf_frame_buffer, | |
2178 | &unit->dwarf_frame_size); | |
d40102a1 | 2179 | if (unit->dwarf_frame_size) |
dda83cd7 SM |
2180 | { |
2181 | asection *got, *txt; | |
2182 | ||
2183 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2184 | that is used for the i386/amd64 target, which currently is | |
2185 | the only target in GCC that supports/uses the | |
2186 | DW_EH_PE_datarel encoding. */ | |
2187 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2188 | if (got) | |
2189 | unit->dbase = got->vma; | |
2190 | ||
2191 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2192 | so far. */ | |
2193 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2194 | if (txt) | |
2195 | unit->tbase = txt->vma; | |
d40102a1 | 2196 | |
a70b8144 | 2197 | try |
8bd90839 FM |
2198 | { |
2199 | frame_ptr = unit->dwarf_frame_buffer; | |
2200 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
4debb237 TT |
2201 | frame_ptr = decode_frame_entry (gdbarch, unit.get (), |
2202 | frame_ptr, 1, | |
93878f47 | 2203 | cie_table, &fde_table, |
8bd90839 FM |
2204 | EH_CIE_OR_FDE_TYPE_ID); |
2205 | } | |
2206 | ||
230d2906 | 2207 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2208 | { |
2209 | warning (_("skipping .eh_frame info of %s: %s"), | |
3d6e9d23 | 2210 | objfile_name (objfile), e.what ()); |
8bd90839 | 2211 | |
a9d65418 | 2212 | fde_table.clear (); |
93878f47 | 2213 | /* The cie_table is discarded below. */ |
8bd90839 | 2214 | } |
d40102a1 | 2215 | |
93878f47 | 2216 | cie_table.clear (); |
dda83cd7 | 2217 | } |
cfc14b3a MK |
2218 | } |
2219 | ||
3017a003 | 2220 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dda83cd7 SM |
2221 | &unit->dwarf_frame_section, |
2222 | &unit->dwarf_frame_buffer, | |
2223 | &unit->dwarf_frame_size); | |
dce234bc | 2224 | if (unit->dwarf_frame_size) |
cfc14b3a | 2225 | { |
a9d65418 | 2226 | size_t num_old_fde_entries = fde_table.size (); |
8bd90839 | 2227 | |
a70b8144 | 2228 | try |
8bd90839 FM |
2229 | { |
2230 | frame_ptr = unit->dwarf_frame_buffer; | |
2231 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
4debb237 | 2232 | frame_ptr = decode_frame_entry (gdbarch, unit.get (), frame_ptr, 0, |
93878f47 | 2233 | cie_table, &fde_table, |
8bd90839 FM |
2234 | EH_CIE_OR_FDE_TYPE_ID); |
2235 | } | |
230d2906 | 2236 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2237 | { |
2238 | warning (_("skipping .debug_frame info of %s: %s"), | |
3d6e9d23 | 2239 | objfile_name (objfile), e.what ()); |
8bd90839 | 2240 | |
a9d65418 | 2241 | fde_table.resize (num_old_fde_entries); |
8bd90839 | 2242 | } |
b01c8410 PP |
2243 | } |
2244 | ||
a9d65418 TT |
2245 | struct dwarf2_fde *fde_prev = NULL; |
2246 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
b01c8410 | 2247 | |
a9d65418 TT |
2248 | /* Prepare FDE table for lookups. */ |
2249 | std::sort (fde_table.begin (), fde_table.end (), fde_is_less_than); | |
875cdfbb | 2250 | |
a9d65418 TT |
2251 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2252 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2253 | ranges because there's no relocation there. It's (offset, | |
2254 | length), not (start, end). On targets where address zero is | |
2255 | just another valid address this can be a problem, since the | |
2256 | FDEs appear to be non-empty in the output --- we could pick | |
2257 | out the wrong FDE. To work around this, when overlaps are | |
2258 | detected, we prefer FDEs that do not start at zero. | |
2259 | ||
2260 | Start by finding the first FDE with non-zero start. Below | |
2261 | we'll discard all FDEs that start at zero and overlap this | |
2262 | one. */ | |
2263 | for (struct dwarf2_fde *fde : fde_table) | |
2264 | { | |
2265 | if (fde->initial_location != 0) | |
875cdfbb | 2266 | { |
a9d65418 TT |
2267 | first_non_zero_fde = fde; |
2268 | break; | |
875cdfbb | 2269 | } |
a9d65418 TT |
2270 | } |
2271 | ||
2272 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2273 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2274 | Also discard leftovers from --gc-sections. */ | |
2275 | for (struct dwarf2_fde *fde : fde_table) | |
2276 | { | |
2277 | if (fde->initial_location == 0 | |
2278 | && first_non_zero_fde != NULL | |
2279 | && (first_non_zero_fde->initial_location | |
2280 | < fde->initial_location + fde->address_range)) | |
2281 | continue; | |
2282 | ||
2283 | if (fde_prev != NULL | |
2284 | && fde_prev->initial_location == fde->initial_location) | |
2285 | continue; | |
b01c8410 | 2286 | |
a7a3ae5c | 2287 | unit->fde_table.push_back (fde); |
a9d65418 | 2288 | fde_prev = fde; |
cfc14b3a | 2289 | } |
a7a3ae5c | 2290 | unit->fde_table.shrink_to_fit (); |
be391dca | 2291 | |
3d4560f7 | 2292 | set_comp_unit (objfile, unit.release ()); |
cfc14b3a | 2293 | } |
0d0e1a63 | 2294 | |
3c3bb058 AB |
2295 | /* Handle 'maintenance show dwarf unwinders'. */ |
2296 | ||
2297 | static void | |
2298 | show_dwarf_unwinders_enabled_p (struct ui_file *file, int from_tty, | |
2299 | struct cmd_list_element *c, | |
2300 | const char *value) | |
2301 | { | |
2302 | fprintf_filtered (file, | |
2303 | _("The DWARF stack unwinders are currently %s.\n"), | |
2304 | value); | |
2305 | } | |
2306 | ||
6c265988 | 2307 | void _initialize_dwarf2_frame (); |
0d0e1a63 | 2308 | void |
6c265988 | 2309 | _initialize_dwarf2_frame () |
0d0e1a63 | 2310 | { |
030f20e1 | 2311 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
1c90d9f0 | 2312 | |
3c3bb058 AB |
2313 | add_setshow_boolean_cmd ("unwinders", class_obscure, |
2314 | &dwarf2_frame_unwinders_enabled_p , _("\ | |
2315 | Set whether the DWARF stack frame unwinders are used."), _("\ | |
2316 | Show whether the DWARF stack frame unwinders are used."), _("\ | |
2317 | When enabled the DWARF stack frame unwinders can be used for architectures\n\ | |
2318 | that support the DWARF unwinders. Enabling the DWARF unwinders for an\n\ | |
2319 | architecture that doesn't support them will have no effect."), | |
2320 | NULL, | |
2321 | show_dwarf_unwinders_enabled_p, | |
2322 | &set_dwarf_cmdlist, | |
2323 | &show_dwarf_cmdlist); | |
2324 | ||
1c90d9f0 | 2325 | #if GDB_SELF_TEST |
1526853e SM |
2326 | selftests::register_test_foreach_arch ("execute_cfa_program", |
2327 | selftests::execute_cfa_program_test); | |
1c90d9f0 | 2328 | #endif |
0d0e1a63 | 2329 | } |