Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
b811d2c2 | 3 | Copyright (C) 2003-2020 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" | |
4de283e4 | 40 | #include "ax.h" |
82ca8957 TT |
41 | #include "dwarf2/loc.h" |
42 | #include "dwarf2/frame-tailcall.h" | |
35e65c49 | 43 | #include "gdbsupport/gdb_binary_search.h" |
1c90d9f0 | 44 | #if GDB_SELF_TEST |
268a13a5 | 45 | #include "gdbsupport/selftest.h" |
1c90d9f0 YQ |
46 | #include "selftest-arch.h" |
47 | #endif | |
93878f47 | 48 | #include <unordered_map> |
cfc14b3a | 49 | |
39ef2f62 CB |
50 | #include <algorithm> |
51 | ||
ae0d2f24 UW |
52 | struct comp_unit; |
53 | ||
cfc14b3a MK |
54 | /* Call Frame Information (CFI). */ |
55 | ||
56 | /* Common Information Entry (CIE). */ | |
57 | ||
58 | struct dwarf2_cie | |
59 | { | |
ae0d2f24 UW |
60 | /* Computation Unit for this CIE. */ |
61 | struct comp_unit *unit; | |
62 | ||
cfc14b3a MK |
63 | /* Offset into the .debug_frame section where this CIE was found. |
64 | Used to identify this CIE. */ | |
65 | ULONGEST cie_pointer; | |
66 | ||
67 | /* Constant that is factored out of all advance location | |
68 | instructions. */ | |
69 | ULONGEST code_alignment_factor; | |
70 | ||
71 | /* Constants that is factored out of all offset instructions. */ | |
72 | LONGEST data_alignment_factor; | |
73 | ||
74 | /* Return address column. */ | |
75 | ULONGEST return_address_register; | |
76 | ||
77 | /* Instruction sequence to initialize a register set. */ | |
f664829e DE |
78 | const gdb_byte *initial_instructions; |
79 | const gdb_byte *end; | |
cfc14b3a | 80 | |
303b6f5d DJ |
81 | /* Saved augmentation, in case it's needed later. */ |
82 | char *augmentation; | |
83 | ||
cfc14b3a | 84 | /* Encoding of addresses. */ |
852483bc | 85 | gdb_byte encoding; |
cfc14b3a | 86 | |
ae0d2f24 UW |
87 | /* Target address size in bytes. */ |
88 | int addr_size; | |
89 | ||
0963b4bd | 90 | /* Target pointer size in bytes. */ |
8da614df CV |
91 | int ptr_size; |
92 | ||
7131cb6e RH |
93 | /* True if a 'z' augmentation existed. */ |
94 | unsigned char saw_z_augmentation; | |
95 | ||
56c987f6 AO |
96 | /* True if an 'S' augmentation existed. */ |
97 | unsigned char signal_frame; | |
98 | ||
303b6f5d DJ |
99 | /* The version recorded in the CIE. */ |
100 | unsigned char version; | |
2dc7f7b3 TT |
101 | |
102 | /* The segment size. */ | |
103 | unsigned char segment_size; | |
b01c8410 | 104 | }; |
303b6f5d | 105 | |
93878f47 TT |
106 | /* The CIE table is used to find CIEs during parsing, but then |
107 | discarded. It maps from the CIE's offset to the CIE. */ | |
108 | typedef std::unordered_map<ULONGEST, dwarf2_cie *> dwarf2_cie_table; | |
cfc14b3a MK |
109 | |
110 | /* Frame Description Entry (FDE). */ | |
111 | ||
112 | struct dwarf2_fde | |
113 | { | |
114 | /* CIE for this FDE. */ | |
115 | struct dwarf2_cie *cie; | |
116 | ||
117 | /* First location associated with this FDE. */ | |
118 | CORE_ADDR initial_location; | |
119 | ||
120 | /* Number of bytes of program instructions described by this FDE. */ | |
121 | CORE_ADDR address_range; | |
122 | ||
123 | /* Instruction sequence. */ | |
f664829e DE |
124 | const gdb_byte *instructions; |
125 | const gdb_byte *end; | |
cfc14b3a | 126 | |
4bf8967c AS |
127 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
128 | section. */ | |
129 | unsigned char eh_frame_p; | |
b01c8410 | 130 | }; |
4bf8967c | 131 | |
b01c8410 PP |
132 | struct dwarf2_fde_table |
133 | { | |
134 | int num_entries; | |
135 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
136 | }; |
137 | ||
ae0d2f24 UW |
138 | /* A minimal decoding of DWARF2 compilation units. We only decode |
139 | what's needed to get to the call frame information. */ | |
140 | ||
141 | struct comp_unit | |
142 | { | |
143 | /* Keep the bfd convenient. */ | |
144 | bfd *abfd; | |
145 | ||
146 | struct objfile *objfile; | |
147 | ||
ae0d2f24 | 148 | /* Pointer to the .debug_frame section loaded into memory. */ |
d521ce57 | 149 | const gdb_byte *dwarf_frame_buffer; |
ae0d2f24 UW |
150 | |
151 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 152 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
153 | |
154 | /* Pointer to the .debug_frame section. */ | |
155 | asection *dwarf_frame_section; | |
156 | ||
157 | /* Base for DW_EH_PE_datarel encodings. */ | |
158 | bfd_vma dbase; | |
159 | ||
160 | /* Base for DW_EH_PE_textrel encodings. */ | |
161 | bfd_vma tbase; | |
162 | }; | |
163 | ||
ac56253d TT |
164 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
165 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
166 | |
167 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
168 | int eh_frame_p); | |
ae0d2f24 UW |
169 | |
170 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 171 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
172 | unsigned int *bytes_read_ptr, |
173 | CORE_ADDR func_base); | |
cfc14b3a MK |
174 | \f |
175 | ||
3c3bb058 | 176 | /* See dwarf2-frame.h. */ |
491144b5 | 177 | bool dwarf2_frame_unwinders_enabled_p = true; |
3c3bb058 | 178 | |
cfc14b3a MK |
179 | /* Store the length the expression for the CFA in the `cfa_reg' field, |
180 | which is unused in that case. */ | |
181 | #define cfa_exp_len cfa_reg | |
182 | ||
afe37d6b YQ |
183 | dwarf2_frame_state::dwarf2_frame_state (CORE_ADDR pc_, struct dwarf2_cie *cie) |
184 | : pc (pc_), data_align (cie->data_alignment_factor), | |
185 | code_align (cie->code_alignment_factor), | |
186 | retaddr_column (cie->return_address_register) | |
cfc14b3a | 187 | { |
afe37d6b | 188 | } |
cfc14b3a MK |
189 | \f |
190 | ||
191 | /* Helper functions for execute_stack_op. */ | |
192 | ||
193 | static CORE_ADDR | |
192ca6d8 | 194 | read_addr_from_reg (struct frame_info *this_frame, int reg) |
cfc14b3a | 195 | { |
4a4e5149 | 196 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
0fde2c53 | 197 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); |
f2da6b3a | 198 | |
2ed3c037 | 199 | return address_from_register (regnum, this_frame); |
cfc14b3a MK |
200 | } |
201 | ||
a6a5a945 LM |
202 | /* Execute the required actions for both the DW_CFA_restore and |
203 | DW_CFA_restore_extended instructions. */ | |
204 | static void | |
205 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
206 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
207 | { | |
208 | ULONGEST reg; | |
209 | ||
a6a5a945 | 210 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); |
1c90d9f0 | 211 | fs->regs.alloc_regs (reg + 1); |
a6a5a945 LM |
212 | |
213 | /* Check if this register was explicitly initialized in the | |
214 | CIE initial instructions. If not, default the rule to | |
215 | UNSPECIFIED. */ | |
780942fc | 216 | if (reg < fs->initial.reg.size ()) |
a6a5a945 LM |
217 | fs->regs.reg[reg] = fs->initial.reg[reg]; |
218 | else | |
219 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
220 | ||
221 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
0fde2c53 DE |
222 | { |
223 | int regnum = dwarf_reg_to_regnum (gdbarch, reg); | |
224 | ||
b98664d3 | 225 | complaint (_("\ |
a6a5a945 | 226 | incomplete CFI data; DW_CFA_restore unspecified\n\ |
5af949e3 | 227 | register %s (#%d) at %s"), |
0fde2c53 DE |
228 | gdbarch_register_name (gdbarch, regnum), regnum, |
229 | paddress (gdbarch, fs->pc)); | |
230 | } | |
a6a5a945 LM |
231 | } |
232 | ||
192ca6d8 | 233 | class dwarf_expr_executor : public dwarf_expr_context |
9e8b7a03 | 234 | { |
192ca6d8 TT |
235 | public: |
236 | ||
237 | struct frame_info *this_frame; | |
238 | ||
632e107b | 239 | CORE_ADDR read_addr_from_reg (int reg) override |
192ca6d8 TT |
240 | { |
241 | return ::read_addr_from_reg (this_frame, reg); | |
242 | } | |
243 | ||
632e107b | 244 | struct value *get_reg_value (struct type *type, int reg) override |
192ca6d8 TT |
245 | { |
246 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
247 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); | |
248 | ||
249 | return value_from_register (type, regnum, this_frame); | |
250 | } | |
251 | ||
632e107b | 252 | void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) override |
192ca6d8 TT |
253 | { |
254 | read_memory (addr, buf, len); | |
255 | } | |
befbff86 | 256 | |
632e107b | 257 | void get_frame_base (const gdb_byte **start, size_t *length) override |
befbff86 TT |
258 | { |
259 | invalid ("DW_OP_fbreg"); | |
260 | } | |
261 | ||
262 | void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, | |
263 | union call_site_parameter_u kind_u, | |
632e107b | 264 | int deref_size) override |
befbff86 | 265 | { |
216f72a1 | 266 | invalid ("DW_OP_entry_value"); |
befbff86 TT |
267 | } |
268 | ||
632e107b | 269 | CORE_ADDR get_object_address () override |
befbff86 TT |
270 | { |
271 | invalid ("DW_OP_push_object_address"); | |
272 | } | |
273 | ||
632e107b | 274 | CORE_ADDR get_frame_cfa () override |
befbff86 TT |
275 | { |
276 | invalid ("DW_OP_call_frame_cfa"); | |
277 | } | |
278 | ||
632e107b | 279 | CORE_ADDR get_tls_address (CORE_ADDR offset) override |
befbff86 TT |
280 | { |
281 | invalid ("DW_OP_form_tls_address"); | |
282 | } | |
283 | ||
632e107b | 284 | void dwarf_call (cu_offset die_offset) override |
befbff86 TT |
285 | { |
286 | invalid ("DW_OP_call*"); | |
287 | } | |
288 | ||
a6b786da KB |
289 | struct value *dwarf_variable_value (sect_offset sect_off) override |
290 | { | |
291 | invalid ("DW_OP_GNU_variable_value"); | |
292 | } | |
293 | ||
632e107b | 294 | CORE_ADDR get_addr_index (unsigned int index) override |
befbff86 | 295 | { |
336d760d | 296 | invalid ("DW_OP_addrx or DW_OP_GNU_addr_index"); |
befbff86 TT |
297 | } |
298 | ||
299 | private: | |
300 | ||
301 | void invalid (const char *op) ATTRIBUTE_NORETURN | |
302 | { | |
303 | error (_("%s is invalid in this context"), op); | |
304 | } | |
9e8b7a03 JK |
305 | }; |
306 | ||
cfc14b3a | 307 | static CORE_ADDR |
0d45f56e | 308 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
309 | CORE_ADDR offset, struct frame_info *this_frame, |
310 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a | 311 | { |
cfc14b3a MK |
312 | CORE_ADDR result; |
313 | ||
192ca6d8 | 314 | dwarf_expr_executor ctx; |
eb115069 | 315 | scoped_value_mark free_values; |
4a227398 | 316 | |
192ca6d8 | 317 | ctx.this_frame = this_frame; |
718b9626 TT |
318 | ctx.gdbarch = get_frame_arch (this_frame); |
319 | ctx.addr_size = addr_size; | |
320 | ctx.ref_addr_size = -1; | |
321 | ctx.offset = offset; | |
cfc14b3a | 322 | |
595d2e30 TT |
323 | ctx.push_address (initial, initial_in_stack_memory); |
324 | ctx.eval (exp, len); | |
cfc14b3a | 325 | |
718b9626 | 326 | if (ctx.location == DWARF_VALUE_MEMORY) |
595d2e30 | 327 | result = ctx.fetch_address (0); |
718b9626 | 328 | else if (ctx.location == DWARF_VALUE_REGISTER) |
192ca6d8 | 329 | result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0))); |
f2c7657e | 330 | else |
cec03d70 TT |
331 | { |
332 | /* This is actually invalid DWARF, but if we ever do run across | |
333 | it somehow, we might as well support it. So, instead, report | |
334 | it as unimplemented. */ | |
3e43a32a MS |
335 | error (_("\ |
336 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 337 | } |
cfc14b3a | 338 | |
cfc14b3a MK |
339 | return result; |
340 | } | |
341 | \f | |
342 | ||
111c6489 JK |
343 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
344 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
345 | execution has stopped, one can resume it on the next call. */ | |
346 | ||
347 | static const gdb_byte * | |
0d45f56e | 348 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff TT |
349 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
350 | CORE_ADDR pc, struct dwarf2_frame_state *fs) | |
cfc14b3a | 351 | { |
ae0d2f24 | 352 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 353 | unsigned int bytes_read; |
e17a4113 | 354 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
355 | |
356 | while (insn_ptr < insn_end && fs->pc <= pc) | |
357 | { | |
852483bc | 358 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
359 | uint64_t utmp, reg; |
360 | int64_t offset; | |
cfc14b3a MK |
361 | |
362 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
363 | fs->pc += (insn & 0x3f) * fs->code_align; | |
364 | else if ((insn & 0xc0) == DW_CFA_offset) | |
365 | { | |
366 | reg = insn & 0x3f; | |
4fc771b8 | 367 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 368 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 369 | offset = utmp * fs->data_align; |
1c90d9f0 | 370 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 371 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
372 | fs->regs.reg[reg].loc.offset = offset; |
373 | } | |
374 | else if ((insn & 0xc0) == DW_CFA_restore) | |
375 | { | |
cfc14b3a | 376 | reg = insn & 0x3f; |
a6a5a945 | 377 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
378 | } |
379 | else | |
380 | { | |
381 | switch (insn) | |
382 | { | |
383 | case DW_CFA_set_loc: | |
ae0d2f24 | 384 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 385 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
386 | &bytes_read, fde->initial_location); |
387 | /* Apply the objfile offset for relocatable objects. */ | |
b3b3bada | 388 | fs->pc += fde->cie->unit->objfile->text_section_offset (); |
cfc14b3a MK |
389 | insn_ptr += bytes_read; |
390 | break; | |
391 | ||
392 | case DW_CFA_advance_loc1: | |
e17a4113 | 393 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
394 | fs->pc += utmp * fs->code_align; |
395 | insn_ptr++; | |
396 | break; | |
397 | case DW_CFA_advance_loc2: | |
e17a4113 | 398 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
399 | fs->pc += utmp * fs->code_align; |
400 | insn_ptr += 2; | |
401 | break; | |
402 | case DW_CFA_advance_loc4: | |
e17a4113 | 403 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
404 | fs->pc += utmp * fs->code_align; |
405 | insn_ptr += 4; | |
406 | break; | |
407 | ||
408 | case DW_CFA_offset_extended: | |
f664829e | 409 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 410 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 411 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 412 | offset = utmp * fs->data_align; |
1c90d9f0 | 413 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 414 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
415 | fs->regs.reg[reg].loc.offset = offset; |
416 | break; | |
417 | ||
418 | case DW_CFA_restore_extended: | |
f664829e | 419 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 420 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
421 | break; |
422 | ||
423 | case DW_CFA_undefined: | |
f664829e | 424 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 425 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 426 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 427 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
428 | break; |
429 | ||
430 | case DW_CFA_same_value: | |
f664829e | 431 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 432 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 433 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 434 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
435 | break; |
436 | ||
437 | case DW_CFA_register: | |
f664829e | 438 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 439 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 440 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 441 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
1c90d9f0 | 442 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 443 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
444 | fs->regs.reg[reg].loc.reg = utmp; |
445 | break; | |
446 | ||
447 | case DW_CFA_remember_state: | |
448 | { | |
449 | struct dwarf2_frame_state_reg_info *new_rs; | |
450 | ||
1c90d9f0 | 451 | new_rs = new dwarf2_frame_state_reg_info (fs->regs); |
cfc14b3a MK |
452 | fs->regs.prev = new_rs; |
453 | } | |
454 | break; | |
455 | ||
456 | case DW_CFA_restore_state: | |
457 | { | |
458 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
459 | ||
50ea7769 MK |
460 | if (old_rs == NULL) |
461 | { | |
b98664d3 | 462 | complaint (_("\ |
5af949e3 UW |
463 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
464 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
465 | } |
466 | else | |
1c90d9f0 | 467 | fs->regs = std::move (*old_rs); |
cfc14b3a MK |
468 | } |
469 | break; | |
470 | ||
471 | case DW_CFA_def_cfa: | |
f664829e DE |
472 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
473 | fs->regs.cfa_reg = reg; | |
474 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
475 | |
476 | if (fs->armcc_cfa_offsets_sf) | |
477 | utmp *= fs->data_align; | |
478 | ||
2fd481e1 PP |
479 | fs->regs.cfa_offset = utmp; |
480 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
481 | break; |
482 | ||
483 | case DW_CFA_def_cfa_register: | |
f664829e DE |
484 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
485 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 PP |
486 | eh_frame_p); |
487 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
488 | break; |
489 | ||
490 | case DW_CFA_def_cfa_offset: | |
f664829e | 491 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
492 | |
493 | if (fs->armcc_cfa_offsets_sf) | |
494 | utmp *= fs->data_align; | |
495 | ||
2fd481e1 | 496 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
497 | /* cfa_how deliberately not set. */ |
498 | break; | |
499 | ||
a8504492 MK |
500 | case DW_CFA_nop: |
501 | break; | |
502 | ||
cfc14b3a | 503 | case DW_CFA_def_cfa_expression: |
f664829e DE |
504 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
505 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
506 | fs->regs.cfa_exp = insn_ptr; |
507 | fs->regs.cfa_how = CFA_EXP; | |
508 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
509 | break; |
510 | ||
511 | case DW_CFA_expression: | |
f664829e | 512 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 513 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 514 | fs->regs.alloc_regs (reg + 1); |
f664829e | 515 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
516 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
517 | fs->regs.reg[reg].loc.exp.len = utmp; | |
05cbe71a | 518 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
519 | insn_ptr += utmp; |
520 | break; | |
521 | ||
a8504492 | 522 | case DW_CFA_offset_extended_sf: |
f664829e | 523 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 524 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 525 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 526 | offset *= fs->data_align; |
1c90d9f0 | 527 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 528 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
529 | fs->regs.reg[reg].loc.offset = offset; |
530 | break; | |
531 | ||
46ea248b | 532 | case DW_CFA_val_offset: |
f664829e | 533 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 534 | fs->regs.alloc_regs (reg + 1); |
f664829e | 535 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
536 | offset = utmp * fs->data_align; |
537 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
538 | fs->regs.reg[reg].loc.offset = offset; | |
539 | break; | |
540 | ||
541 | case DW_CFA_val_offset_sf: | |
f664829e | 542 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 543 | fs->regs.alloc_regs (reg + 1); |
f664829e | 544 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
545 | offset *= fs->data_align; |
546 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
547 | fs->regs.reg[reg].loc.offset = offset; | |
548 | break; | |
549 | ||
550 | case DW_CFA_val_expression: | |
f664829e | 551 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 552 | fs->regs.alloc_regs (reg + 1); |
f664829e | 553 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
554 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
555 | fs->regs.reg[reg].loc.exp.len = utmp; | |
46ea248b AO |
556 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; |
557 | insn_ptr += utmp; | |
558 | break; | |
559 | ||
a8504492 | 560 | case DW_CFA_def_cfa_sf: |
f664829e DE |
561 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
562 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 | 563 | eh_frame_p); |
f664829e | 564 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
565 | fs->regs.cfa_offset = offset * fs->data_align; |
566 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
567 | break; |
568 | ||
569 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 570 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 571 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 572 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
573 | break; |
574 | ||
575 | case DW_CFA_GNU_args_size: | |
576 | /* Ignored. */ | |
f664829e | 577 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
578 | break; |
579 | ||
58894217 | 580 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 581 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 582 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
583 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
584 | offset = utmp * fs->data_align; | |
1c90d9f0 | 585 | fs->regs.alloc_regs (reg + 1); |
58894217 JK |
586 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
587 | fs->regs.reg[reg].loc.offset = -offset; | |
588 | break; | |
589 | ||
cfc14b3a | 590 | default: |
b41c5a85 JW |
591 | if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user) |
592 | { | |
593 | /* Handle vendor-specific CFI for different architectures. */ | |
594 | if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs)) | |
595 | error (_("Call Frame Instruction op %d in vendor extension " | |
596 | "space is not handled on this architecture."), | |
597 | insn); | |
598 | } | |
599 | else | |
600 | internal_error (__FILE__, __LINE__, | |
601 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
602 | } |
603 | } | |
604 | } | |
605 | ||
780942fc | 606 | if (fs->initial.reg.empty ()) |
111c6489 JK |
607 | { |
608 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
1c90d9f0 | 609 | delete fs->regs.prev; |
111c6489 JK |
610 | fs->regs.prev = NULL; |
611 | } | |
612 | ||
613 | return insn_ptr; | |
cfc14b3a | 614 | } |
1c90d9f0 YQ |
615 | |
616 | #if GDB_SELF_TEST | |
617 | ||
618 | namespace selftests { | |
619 | ||
620 | /* Unit test to function execute_cfa_program. */ | |
621 | ||
622 | static void | |
623 | execute_cfa_program_test (struct gdbarch *gdbarch) | |
624 | { | |
625 | struct dwarf2_fde fde; | |
626 | struct dwarf2_cie cie; | |
627 | ||
628 | memset (&fde, 0, sizeof fde); | |
629 | memset (&cie, 0, sizeof cie); | |
630 | ||
631 | cie.data_alignment_factor = -4; | |
632 | cie.code_alignment_factor = 2; | |
633 | fde.cie = &cie; | |
634 | ||
635 | dwarf2_frame_state fs (0, fde.cie); | |
636 | ||
637 | gdb_byte insns[] = | |
638 | { | |
639 | DW_CFA_def_cfa, 1, 4, /* DW_CFA_def_cfa: r1 ofs 4 */ | |
640 | DW_CFA_offset | 0x2, 1, /* DW_CFA_offset: r2 at cfa-4 */ | |
641 | DW_CFA_remember_state, | |
642 | DW_CFA_restore_state, | |
643 | }; | |
644 | ||
645 | const gdb_byte *insn_end = insns + sizeof (insns); | |
646 | const gdb_byte *out = execute_cfa_program (&fde, insns, insn_end, gdbarch, | |
647 | 0, &fs); | |
648 | ||
649 | SELF_CHECK (out == insn_end); | |
650 | SELF_CHECK (fs.pc == 0); | |
651 | ||
652 | /* The instructions above only use r1 and r2, but the register numbers | |
653 | used are adjusted by dwarf2_frame_adjust_regnum. */ | |
654 | auto r1 = dwarf2_frame_adjust_regnum (gdbarch, 1, fde.eh_frame_p); | |
655 | auto r2 = dwarf2_frame_adjust_regnum (gdbarch, 2, fde.eh_frame_p); | |
656 | ||
780942fc | 657 | SELF_CHECK (fs.regs.reg.size () == (std::max (r1, r2) + 1)); |
1c90d9f0 YQ |
658 | |
659 | SELF_CHECK (fs.regs.reg[r2].how == DWARF2_FRAME_REG_SAVED_OFFSET); | |
660 | SELF_CHECK (fs.regs.reg[r2].loc.offset == -4); | |
661 | ||
780942fc | 662 | for (auto i = 0; i < fs.regs.reg.size (); i++) |
1c90d9f0 YQ |
663 | if (i != r2) |
664 | SELF_CHECK (fs.regs.reg[i].how == DWARF2_FRAME_REG_UNSPECIFIED); | |
665 | ||
666 | SELF_CHECK (fs.regs.cfa_reg == 1); | |
667 | SELF_CHECK (fs.regs.cfa_offset == 4); | |
668 | SELF_CHECK (fs.regs.cfa_how == CFA_REG_OFFSET); | |
669 | SELF_CHECK (fs.regs.cfa_exp == NULL); | |
670 | SELF_CHECK (fs.regs.prev == NULL); | |
671 | } | |
672 | ||
673 | } // namespace selftests | |
674 | #endif /* GDB_SELF_TEST */ | |
675 | ||
8f22cb90 | 676 | \f |
cfc14b3a | 677 | |
8f22cb90 | 678 | /* Architecture-specific operations. */ |
cfc14b3a | 679 | |
8f22cb90 MK |
680 | /* Per-architecture data key. */ |
681 | static struct gdbarch_data *dwarf2_frame_data; | |
682 | ||
683 | struct dwarf2_frame_ops | |
684 | { | |
685 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
686 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
687 | struct frame_info *); | |
3ed09a32 | 688 | |
4a4e5149 | 689 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 690 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 691 | |
4fc771b8 DJ |
692 | /* Convert .eh_frame register number to DWARF register number, or |
693 | adjust .debug_frame register number. */ | |
694 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
695 | }; |
696 | ||
8f22cb90 MK |
697 | /* Default architecture-specific register state initialization |
698 | function. */ | |
699 | ||
700 | static void | |
701 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 702 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 703 | struct frame_info *this_frame) |
8f22cb90 MK |
704 | { |
705 | /* If we have a register that acts as a program counter, mark it as | |
706 | a destination for the return address. If we have a register that | |
707 | serves as the stack pointer, arrange for it to be filled with the | |
708 | call frame address (CFA). The other registers are marked as | |
709 | unspecified. | |
710 | ||
711 | We copy the return address to the program counter, since many | |
712 | parts in GDB assume that it is possible to get the return address | |
713 | by unwinding the program counter register. However, on ISA's | |
714 | with a dedicated return address register, the CFI usually only | |
715 | contains information to unwind that return address register. | |
716 | ||
717 | The reason we're treating the stack pointer special here is | |
718 | because in many cases GCC doesn't emit CFI for the stack pointer | |
719 | and implicitly assumes that it is equal to the CFA. This makes | |
720 | some sense since the DWARF specification (version 3, draft 8, | |
721 | p. 102) says that: | |
722 | ||
723 | "Typically, the CFA is defined to be the value of the stack | |
724 | pointer at the call site in the previous frame (which may be | |
725 | different from its value on entry to the current frame)." | |
726 | ||
727 | However, this isn't true for all platforms supported by GCC | |
728 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
729 | their own architecture-specific initialization function. */ | |
05cbe71a | 730 | |
ad010def | 731 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 732 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 733 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
734 | reg->how = DWARF2_FRAME_REG_CFA; |
735 | } | |
05cbe71a | 736 | |
8f22cb90 | 737 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 738 | |
8f22cb90 | 739 | static void * |
030f20e1 | 740 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
741 | { |
742 | struct dwarf2_frame_ops *ops; | |
743 | ||
030f20e1 | 744 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
745 | ops->init_reg = dwarf2_frame_default_init_reg; |
746 | return ops; | |
747 | } | |
05cbe71a | 748 | |
8f22cb90 MK |
749 | /* Set the architecture-specific register state initialization |
750 | function for GDBARCH to INIT_REG. */ | |
751 | ||
752 | void | |
753 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
754 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
755 | struct dwarf2_frame_state_reg *, |
756 | struct frame_info *)) | |
8f22cb90 | 757 | { |
9a3c8263 SM |
758 | struct dwarf2_frame_ops *ops |
759 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 760 | |
8f22cb90 MK |
761 | ops->init_reg = init_reg; |
762 | } | |
763 | ||
764 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
765 | |
766 | static void | |
767 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 768 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 769 | struct frame_info *this_frame) |
05cbe71a | 770 | { |
9a3c8263 SM |
771 | struct dwarf2_frame_ops *ops |
772 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 773 | |
4a4e5149 | 774 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 775 | } |
3ed09a32 DJ |
776 | |
777 | /* Set the architecture-specific signal trampoline recognition | |
778 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
779 | ||
780 | void | |
781 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
782 | int (*signal_frame_p) (struct gdbarch *, | |
783 | struct frame_info *)) | |
784 | { | |
9a3c8263 SM |
785 | struct dwarf2_frame_ops *ops |
786 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
787 | |
788 | ops->signal_frame_p = signal_frame_p; | |
789 | } | |
790 | ||
791 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 792 | THIS_FRAME. */ |
3ed09a32 DJ |
793 | |
794 | static int | |
795 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 796 | struct frame_info *this_frame) |
3ed09a32 | 797 | { |
9a3c8263 SM |
798 | struct dwarf2_frame_ops *ops |
799 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
800 | |
801 | if (ops->signal_frame_p == NULL) | |
802 | return 0; | |
4a4e5149 | 803 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 804 | } |
4bf8967c | 805 | |
4fc771b8 DJ |
806 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
807 | register numbers. */ | |
4bf8967c AS |
808 | |
809 | void | |
4fc771b8 DJ |
810 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
811 | int (*adjust_regnum) (struct gdbarch *, | |
812 | int, int)) | |
4bf8967c | 813 | { |
9a3c8263 SM |
814 | struct dwarf2_frame_ops *ops |
815 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 816 | |
4fc771b8 | 817 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
818 | } |
819 | ||
4fc771b8 DJ |
820 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
821 | register. */ | |
4bf8967c | 822 | |
4fc771b8 | 823 | static int |
3e43a32a MS |
824 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
825 | int regnum, int eh_frame_p) | |
4bf8967c | 826 | { |
9a3c8263 SM |
827 | struct dwarf2_frame_ops *ops |
828 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 829 | |
4fc771b8 | 830 | if (ops->adjust_regnum == NULL) |
4bf8967c | 831 | return regnum; |
4fc771b8 | 832 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 833 | } |
303b6f5d DJ |
834 | |
835 | static void | |
836 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
837 | struct dwarf2_fde *fde) | |
838 | { | |
43f3e411 | 839 | struct compunit_symtab *cust; |
303b6f5d | 840 | |
43f3e411 DE |
841 | cust = find_pc_compunit_symtab (fs->pc); |
842 | if (cust == NULL) | |
303b6f5d DJ |
843 | return; |
844 | ||
43f3e411 | 845 | if (producer_is_realview (COMPUNIT_PRODUCER (cust))) |
a6c727b2 DJ |
846 | { |
847 | if (fde->cie->version == 1) | |
848 | fs->armcc_cfa_offsets_sf = 1; | |
849 | ||
850 | if (fde->cie->version == 1) | |
851 | fs->armcc_cfa_offsets_reversed = 1; | |
852 | ||
853 | /* The reversed offset problem is present in some compilers | |
854 | using DWARF3, but it was eventually fixed. Check the ARM | |
855 | defined augmentations, which are in the format "armcc" followed | |
856 | by a list of one-character options. The "+" option means | |
857 | this problem is fixed (no quirk needed). If the armcc | |
858 | augmentation is missing, the quirk is needed. */ | |
859 | if (fde->cie->version == 3 | |
61012eef | 860 | && (!startswith (fde->cie->augmentation, "armcc") |
a6c727b2 DJ |
861 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) |
862 | fs->armcc_cfa_offsets_reversed = 1; | |
863 | ||
864 | return; | |
865 | } | |
303b6f5d | 866 | } |
8f22cb90 MK |
867 | \f |
868 | ||
a8fd5589 TT |
869 | /* See dwarf2-frame.h. */ |
870 | ||
871 | int | |
872 | dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc, | |
873 | struct dwarf2_per_cu_data *data, | |
874 | int *regnum_out, LONGEST *offset_out, | |
875 | CORE_ADDR *text_offset_out, | |
876 | const gdb_byte **cfa_start_out, | |
877 | const gdb_byte **cfa_end_out) | |
9f6f94ff | 878 | { |
9f6f94ff | 879 | struct dwarf2_fde *fde; |
22e048c9 | 880 | CORE_ADDR text_offset; |
afe37d6b | 881 | CORE_ADDR pc1 = pc; |
9f6f94ff TT |
882 | |
883 | /* Find the correct FDE. */ | |
afe37d6b | 884 | fde = dwarf2_frame_find_fde (&pc1, &text_offset); |
9f6f94ff TT |
885 | if (fde == NULL) |
886 | error (_("Could not compute CFA; needed to translate this expression")); | |
887 | ||
afe37d6b | 888 | dwarf2_frame_state fs (pc1, fde->cie); |
9f6f94ff TT |
889 | |
890 | /* Check for "quirks" - known bugs in producers. */ | |
891 | dwarf2_frame_find_quirks (&fs, fde); | |
892 | ||
893 | /* First decode all the insns in the CIE. */ | |
894 | execute_cfa_program (fde, fde->cie->initial_instructions, | |
895 | fde->cie->end, gdbarch, pc, &fs); | |
896 | ||
897 | /* Save the initialized register set. */ | |
898 | fs.initial = fs.regs; | |
9f6f94ff TT |
899 | |
900 | /* Then decode the insns in the FDE up to our target PC. */ | |
901 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs); | |
902 | ||
903 | /* Calculate the CFA. */ | |
904 | switch (fs.regs.cfa_how) | |
905 | { | |
906 | case CFA_REG_OFFSET: | |
907 | { | |
0fde2c53 | 908 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg); |
a8fd5589 TT |
909 | |
910 | *regnum_out = regnum; | |
911 | if (fs.armcc_cfa_offsets_reversed) | |
912 | *offset_out = -fs.regs.cfa_offset; | |
913 | else | |
914 | *offset_out = fs.regs.cfa_offset; | |
915 | return 1; | |
9f6f94ff | 916 | } |
9f6f94ff TT |
917 | |
918 | case CFA_EXP: | |
a8fd5589 TT |
919 | *text_offset_out = text_offset; |
920 | *cfa_start_out = fs.regs.cfa_exp; | |
921 | *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len; | |
922 | return 0; | |
9f6f94ff TT |
923 | |
924 | default: | |
925 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
926 | } | |
927 | } | |
928 | ||
929 | \f | |
8f22cb90 MK |
930 | struct dwarf2_frame_cache |
931 | { | |
932 | /* DWARF Call Frame Address. */ | |
933 | CORE_ADDR cfa; | |
934 | ||
8fbca658 PA |
935 | /* Set if the return address column was marked as unavailable |
936 | (required non-collected memory or registers to compute). */ | |
937 | int unavailable_retaddr; | |
938 | ||
0228dfb9 DJ |
939 | /* Set if the return address column was marked as undefined. */ |
940 | int undefined_retaddr; | |
941 | ||
8f22cb90 MK |
942 | /* Saved registers, indexed by GDB register number, not by DWARF |
943 | register number. */ | |
944 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
945 | |
946 | /* Return address register. */ | |
947 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
948 | |
949 | /* Target address size in bytes. */ | |
950 | int addr_size; | |
ac56253d TT |
951 | |
952 | /* The .text offset. */ | |
953 | CORE_ADDR text_offset; | |
111c6489 | 954 | |
1ec56e88 PA |
955 | /* True if we already checked whether this frame is the bottom frame |
956 | of a virtual tail call frame chain. */ | |
957 | int checked_tailcall_bottom; | |
958 | ||
111c6489 JK |
959 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME |
960 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
961 | involved. Non-bottom frames of a virtual tail call frames chain use | |
962 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
963 | them. */ | |
964 | void *tailcall_cache; | |
1ec56e88 PA |
965 | |
966 | /* The number of bytes to subtract from TAILCALL_FRAME frames frame | |
967 | base to get the SP, to simulate the return address pushed on the | |
968 | stack. */ | |
969 | LONGEST entry_cfa_sp_offset; | |
970 | int entry_cfa_sp_offset_p; | |
8f22cb90 | 971 | }; |
05cbe71a | 972 | |
b9362cc7 | 973 | static struct dwarf2_frame_cache * |
4a4e5149 | 974 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 975 | { |
4a4e5149 | 976 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
f6efe3f8 | 977 | const int num_regs = gdbarch_num_cooked_regs (gdbarch); |
cfc14b3a | 978 | struct dwarf2_frame_cache *cache; |
cfc14b3a | 979 | struct dwarf2_fde *fde; |
111c6489 | 980 | CORE_ADDR entry_pc; |
111c6489 | 981 | const gdb_byte *instr; |
cfc14b3a MK |
982 | |
983 | if (*this_cache) | |
9a3c8263 | 984 | return (struct dwarf2_frame_cache *) *this_cache; |
cfc14b3a MK |
985 | |
986 | /* Allocate a new cache. */ | |
987 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
988 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 989 | *this_cache = cache; |
cfc14b3a | 990 | |
cfc14b3a MK |
991 | /* Unwind the PC. |
992 | ||
4a4e5149 | 993 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 994 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 995 | its return address. As a result the return address will |
cfc14b3a | 996 | point at some random instruction, and the CFI for that |
e4e9607c | 997 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
998 | this problem by substracting 1 from the return address to get an |
999 | address in the middle of a presumed call instruction (or the | |
1000 | instruction in the associated delay slot). This should only be | |
1001 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 1002 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 1003 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
1004 | reliable the method is though; there is the potential for the |
1005 | register state pre-call being different to that on return. */ | |
afe37d6b | 1006 | CORE_ADDR pc1 = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1007 | |
1008 | /* Find the correct FDE. */ | |
afe37d6b | 1009 | fde = dwarf2_frame_find_fde (&pc1, &cache->text_offset); |
cfc14b3a MK |
1010 | gdb_assert (fde != NULL); |
1011 | ||
afe37d6b YQ |
1012 | /* Allocate and initialize the frame state. */ |
1013 | struct dwarf2_frame_state fs (pc1, fde->cie); | |
1014 | ||
ae0d2f24 | 1015 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1016 | |
303b6f5d | 1017 | /* Check for "quirks" - known bugs in producers. */ |
afe37d6b | 1018 | dwarf2_frame_find_quirks (&fs, fde); |
303b6f5d | 1019 | |
cfc14b3a | 1020 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1021 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 | 1022 | fde->cie->end, gdbarch, |
afe37d6b | 1023 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a MK |
1024 | |
1025 | /* Save the initialized register set. */ | |
afe37d6b | 1026 | fs.initial = fs.regs; |
cfc14b3a | 1027 | |
1aff7173 KB |
1028 | /* Fetching the entry pc for THIS_FRAME won't necessarily result |
1029 | in an address that's within the range of FDE locations. This | |
1030 | is due to the possibility of the function occupying non-contiguous | |
1031 | ranges. */ | |
1032 | if (get_frame_func_if_available (this_frame, &entry_pc) | |
1033 | && fde->initial_location <= entry_pc | |
1034 | && entry_pc < fde->initial_location + fde->address_range) | |
111c6489 JK |
1035 | { |
1036 | /* Decode the insns in the FDE up to the entry PC. */ | |
1037 | instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, | |
afe37d6b | 1038 | entry_pc, &fs); |
111c6489 | 1039 | |
afe37d6b YQ |
1040 | if (fs.regs.cfa_how == CFA_REG_OFFSET |
1041 | && (dwarf_reg_to_regnum (gdbarch, fs.regs.cfa_reg) | |
111c6489 JK |
1042 | == gdbarch_sp_regnum (gdbarch))) |
1043 | { | |
afe37d6b | 1044 | cache->entry_cfa_sp_offset = fs.regs.cfa_offset; |
1ec56e88 | 1045 | cache->entry_cfa_sp_offset_p = 1; |
111c6489 JK |
1046 | } |
1047 | } | |
1048 | else | |
1049 | instr = fde->instructions; | |
1050 | ||
cfc14b3a | 1051 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1052 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
afe37d6b | 1053 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a | 1054 | |
a70b8144 | 1055 | try |
cfc14b3a | 1056 | { |
8fbca658 | 1057 | /* Calculate the CFA. */ |
afe37d6b | 1058 | switch (fs.regs.cfa_how) |
8fbca658 PA |
1059 | { |
1060 | case CFA_REG_OFFSET: | |
afe37d6b YQ |
1061 | cache->cfa = read_addr_from_reg (this_frame, fs.regs.cfa_reg); |
1062 | if (fs.armcc_cfa_offsets_reversed) | |
1063 | cache->cfa -= fs.regs.cfa_offset; | |
8fbca658 | 1064 | else |
afe37d6b | 1065 | cache->cfa += fs.regs.cfa_offset; |
8fbca658 PA |
1066 | break; |
1067 | ||
1068 | case CFA_EXP: | |
1069 | cache->cfa = | |
afe37d6b | 1070 | execute_stack_op (fs.regs.cfa_exp, fs.regs.cfa_exp_len, |
8fbca658 PA |
1071 | cache->addr_size, cache->text_offset, |
1072 | this_frame, 0, 0); | |
1073 | break; | |
1074 | ||
1075 | default: | |
1076 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1077 | } | |
1078 | } | |
230d2906 | 1079 | catch (const gdb_exception_error &ex) |
8fbca658 PA |
1080 | { |
1081 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1082 | { | |
1083 | cache->unavailable_retaddr = 1; | |
1084 | return cache; | |
1085 | } | |
cfc14b3a | 1086 | |
eedc3f4f | 1087 | throw; |
cfc14b3a MK |
1088 | } |
1089 | ||
05cbe71a | 1090 | /* Initialize the register state. */ |
3e2c4033 AC |
1091 | { |
1092 | int regnum; | |
e4e9607c | 1093 | |
3e2c4033 | 1094 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1095 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1096 | } |
1097 | ||
1098 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1099 | location information in the cache. Note that we don't skip the |
1100 | return address column; it's perfectly all right for it to | |
0fde2c53 | 1101 | correspond to a real register. */ |
3e2c4033 AC |
1102 | { |
1103 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1104 | |
780942fc | 1105 | for (column = 0; column < fs.regs.reg.size (); column++) |
3e2c4033 | 1106 | { |
3e2c4033 | 1107 | /* Use the GDB register number as the destination index. */ |
0fde2c53 | 1108 | int regnum = dwarf_reg_to_regnum (gdbarch, column); |
3e2c4033 | 1109 | |
0fde2c53 | 1110 | /* Protect against a target returning a bad register. */ |
3e2c4033 AC |
1111 | if (regnum < 0 || regnum >= num_regs) |
1112 | continue; | |
1113 | ||
1114 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1115 | of all debug info registers. If it doesn't, complain (but |
1116 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1117 | unspecified register implies "same value" when CFI (draft |
1118 | 7) specifies nothing at all. Such a register could equally | |
1119 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1120 | isn't sufficient; it only checks that all registers in the |
1121 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1122 | problems when a debug info register falls outside of the |
e4e9607c | 1123 | table. We need a way of iterating through all the valid |
3e2c4033 | 1124 | DWARF2 register numbers. */ |
afe37d6b | 1125 | if (fs.regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1126 | { |
1127 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
b98664d3 | 1128 | complaint (_("\ |
5af949e3 | 1129 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1130 | gdbarch_register_name (gdbarch, regnum), |
afe37d6b | 1131 | paddress (gdbarch, fs.pc)); |
f059bf6f | 1132 | } |
35889917 | 1133 | else |
afe37d6b | 1134 | cache->reg[regnum] = fs.regs.reg[column]; |
3e2c4033 AC |
1135 | } |
1136 | } | |
cfc14b3a | 1137 | |
8d5a9abc MK |
1138 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1139 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1140 | { |
1141 | int regnum; | |
1142 | ||
1143 | for (regnum = 0; regnum < num_regs; regnum++) | |
1144 | { | |
8d5a9abc MK |
1145 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1146 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1147 | { |
780942fc TT |
1148 | const std::vector<struct dwarf2_frame_state_reg> ®s |
1149 | = fs.regs.reg; | |
1150 | ULONGEST retaddr_column = fs.retaddr_column; | |
05cbe71a | 1151 | |
d4f10bf2 MK |
1152 | /* It seems rather bizarre to specify an "empty" column as |
1153 | the return adress column. However, this is exactly | |
1154 | what GCC does on some targets. It turns out that GCC | |
1155 | assumes that the return address can be found in the | |
1156 | register corresponding to the return address column. | |
8d5a9abc MK |
1157 | Incidentally, that's how we should treat a return |
1158 | address column specifying "same value" too. */ | |
780942fc TT |
1159 | if (fs.retaddr_column < fs.regs.reg.size () |
1160 | && regs[retaddr_column].how != DWARF2_FRAME_REG_UNSPECIFIED | |
1161 | && regs[retaddr_column].how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1162 | { |
1163 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
780942fc | 1164 | cache->reg[regnum] = regs[retaddr_column]; |
8d5a9abc | 1165 | else |
780942fc | 1166 | cache->retaddr_reg = regs[retaddr_column]; |
8d5a9abc | 1167 | } |
35889917 MK |
1168 | else |
1169 | { | |
8d5a9abc MK |
1170 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1171 | { | |
afe37d6b | 1172 | cache->reg[regnum].loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1173 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; |
1174 | } | |
1175 | else | |
1176 | { | |
afe37d6b | 1177 | cache->retaddr_reg.loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1178 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; |
1179 | } | |
35889917 MK |
1180 | } |
1181 | } | |
1182 | } | |
1183 | } | |
cfc14b3a | 1184 | |
780942fc | 1185 | if (fs.retaddr_column < fs.regs.reg.size () |
afe37d6b | 1186 | && fs.regs.reg[fs.retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) |
0228dfb9 DJ |
1187 | cache->undefined_retaddr = 1; |
1188 | ||
cfc14b3a MK |
1189 | return cache; |
1190 | } | |
1191 | ||
8fbca658 PA |
1192 | static enum unwind_stop_reason |
1193 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1194 | void **this_cache) | |
1195 | { | |
1196 | struct dwarf2_frame_cache *cache | |
1197 | = dwarf2_frame_cache (this_frame, this_cache); | |
1198 | ||
1199 | if (cache->unavailable_retaddr) | |
1200 | return UNWIND_UNAVAILABLE; | |
1201 | ||
1202 | if (cache->undefined_retaddr) | |
1203 | return UNWIND_OUTERMOST; | |
1204 | ||
1205 | return UNWIND_NO_REASON; | |
1206 | } | |
1207 | ||
cfc14b3a | 1208 | static void |
4a4e5149 | 1209 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1210 | struct frame_id *this_id) |
1211 | { | |
1212 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1213 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1214 | |
8fbca658 | 1215 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1216 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1217 | else if (cache->undefined_retaddr) | |
8fbca658 | 1218 | return; |
5ce0145d PA |
1219 | else |
1220 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1221 | } |
1222 | ||
4a4e5149 DJ |
1223 | static struct value * |
1224 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1225 | int regnum) | |
93d42b30 | 1226 | { |
4a4e5149 | 1227 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1228 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1229 | dwarf2_frame_cache (this_frame, this_cache); |
1230 | CORE_ADDR addr; | |
1231 | int realnum; | |
cfc14b3a | 1232 | |
1ec56e88 PA |
1233 | /* Check whether THIS_FRAME is the bottom frame of a virtual tail |
1234 | call frame chain. */ | |
1235 | if (!cache->checked_tailcall_bottom) | |
1236 | { | |
1237 | cache->checked_tailcall_bottom = 1; | |
1238 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, | |
1239 | (cache->entry_cfa_sp_offset_p | |
1240 | ? &cache->entry_cfa_sp_offset : NULL)); | |
1241 | } | |
1242 | ||
111c6489 JK |
1243 | /* Non-bottom frames of a virtual tail call frames chain use |
1244 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1245 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1246 | unwind the register, tail call frames are assumed to have the register set | |
1247 | of the top caller. */ | |
1248 | if (cache->tailcall_cache) | |
1249 | { | |
1250 | struct value *val; | |
1251 | ||
1252 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1253 | &cache->tailcall_cache, | |
1254 | regnum); | |
1255 | if (val) | |
1256 | return val; | |
1257 | } | |
1258 | ||
cfc14b3a MK |
1259 | switch (cache->reg[regnum].how) |
1260 | { | |
05cbe71a | 1261 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1262 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1263 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1264 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1265 | |
05cbe71a | 1266 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1267 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1268 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1269 | |
05cbe71a | 1270 | case DWARF2_FRAME_REG_SAVED_REG: |
0fde2c53 DE |
1271 | realnum = dwarf_reg_to_regnum_or_error |
1272 | (gdbarch, cache->reg[regnum].loc.reg); | |
4a4e5149 | 1273 | return frame_unwind_got_register (this_frame, regnum, realnum); |
cfc14b3a | 1274 | |
05cbe71a | 1275 | case DWARF2_FRAME_REG_SAVED_EXP: |
b348037f YQ |
1276 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1277 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1278 | cache->addr_size, cache->text_offset, |
1279 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1280 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1281 | |
46ea248b | 1282 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1283 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1284 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1285 | |
1286 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
b348037f YQ |
1287 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1288 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1289 | cache->addr_size, cache->text_offset, |
1290 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1291 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1292 | |
05cbe71a | 1293 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1294 | /* GCC, in its infinite wisdom decided to not provide unwind |
1295 | information for registers that are "same value". Since | |
1296 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1297 | registers are actually undefined (which is different to CFI | |
1298 | "undefined"). Code above issues a complaint about this. | |
1299 | Here just fudge the books, assume GCC, and that the value is | |
1300 | more inner on the stack. */ | |
4a4e5149 | 1301 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1302 | |
05cbe71a | 1303 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1304 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1305 | |
05cbe71a | 1306 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1307 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1308 | |
ea7963f0 | 1309 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1310 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1311 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1312 | |
8d5a9abc | 1313 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 | 1314 | addr = cache->reg[regnum].loc.offset; |
0fde2c53 | 1315 | regnum = dwarf_reg_to_regnum_or_error |
4a4e5149 DJ |
1316 | (gdbarch, cache->retaddr_reg.loc.reg); |
1317 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1318 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1319 | |
b39cc962 DJ |
1320 | case DWARF2_FRAME_REG_FN: |
1321 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1322 | ||
cfc14b3a | 1323 | default: |
e2e0b3e5 | 1324 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1325 | } |
1326 | } | |
1327 | ||
111c6489 JK |
1328 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1329 | call frames chain. */ | |
1330 | ||
1331 | static void | |
1332 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1333 | { | |
1334 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1335 | ||
1336 | if (cache->tailcall_cache) | |
1337 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1338 | } | |
1339 | ||
4a4e5149 DJ |
1340 | static int |
1341 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1342 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1343 | { |
3c3bb058 AB |
1344 | if (!dwarf2_frame_unwinders_enabled_p) |
1345 | return 0; | |
1346 | ||
30baf67b | 1347 | /* Grab an address that is guaranteed to reside somewhere within the |
4a4e5149 | 1348 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1349 | end up returning something past the end of this function's body. |
1350 | If the frame we're sniffing for is a signal frame whose start | |
1351 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1352 | extend one byte before its start address or we could potentially |
1353 | select the FDE of the previous function. */ | |
1354 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1355 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1356 | |
56c987f6 | 1357 | if (!fde) |
4a4e5149 | 1358 | return 0; |
3ed09a32 DJ |
1359 | |
1360 | /* On some targets, signal trampolines may have unwind information. | |
1361 | We need to recognize them so that we set the frame type | |
1362 | correctly. */ | |
1363 | ||
56c987f6 | 1364 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1365 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1366 | this_frame)) | |
1367 | return self->type == SIGTRAMP_FRAME; | |
1368 | ||
111c6489 JK |
1369 | if (self->type != NORMAL_FRAME) |
1370 | return 0; | |
1371 | ||
111c6489 | 1372 | return 1; |
4a4e5149 DJ |
1373 | } |
1374 | ||
1375 | static const struct frame_unwind dwarf2_frame_unwind = | |
1376 | { | |
1377 | NORMAL_FRAME, | |
8fbca658 | 1378 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1379 | dwarf2_frame_this_id, |
1380 | dwarf2_frame_prev_register, | |
1381 | NULL, | |
111c6489 JK |
1382 | dwarf2_frame_sniffer, |
1383 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1384 | }; |
1385 | ||
1386 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1387 | { | |
1388 | SIGTRAMP_FRAME, | |
8fbca658 | 1389 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1390 | dwarf2_frame_this_id, |
1391 | dwarf2_frame_prev_register, | |
1392 | NULL, | |
111c6489 JK |
1393 | dwarf2_frame_sniffer, |
1394 | ||
1395 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1396 | NULL | |
4a4e5149 | 1397 | }; |
cfc14b3a | 1398 | |
4a4e5149 DJ |
1399 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1400 | ||
1401 | void | |
1402 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1403 | { | |
111c6489 JK |
1404 | /* TAILCALL_FRAME must be first to find the record by |
1405 | dwarf2_tailcall_sniffer_first. */ | |
1406 | frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind); | |
1407 | ||
4a4e5149 DJ |
1408 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); |
1409 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1410 | } |
1411 | \f | |
1412 | ||
1413 | /* There is no explicitly defined relationship between the CFA and the | |
1414 | location of frame's local variables and arguments/parameters. | |
1415 | Therefore, frame base methods on this page should probably only be | |
1416 | used as a last resort, just to avoid printing total garbage as a | |
1417 | response to the "info frame" command. */ | |
1418 | ||
1419 | static CORE_ADDR | |
4a4e5149 | 1420 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1421 | { |
1422 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1423 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1424 | |
1425 | return cache->cfa; | |
1426 | } | |
1427 | ||
1428 | static const struct frame_base dwarf2_frame_base = | |
1429 | { | |
1430 | &dwarf2_frame_unwind, | |
1431 | dwarf2_frame_base_address, | |
1432 | dwarf2_frame_base_address, | |
1433 | dwarf2_frame_base_address | |
1434 | }; | |
1435 | ||
1436 | const struct frame_base * | |
4a4e5149 | 1437 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1438 | { |
4a4e5149 | 1439 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1440 | |
ac56253d | 1441 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1442 | return &dwarf2_frame_base; |
1443 | ||
1444 | return NULL; | |
1445 | } | |
e7802207 TT |
1446 | |
1447 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1448 | the DWARF unwinder. This is used to implement | |
1449 | DW_OP_call_frame_cfa. */ | |
1450 | ||
1451 | CORE_ADDR | |
1452 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1453 | { | |
0b722aec MM |
1454 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1455 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1456 | throw_error (NOT_AVAILABLE_ERROR, | |
1457 | _("cfa not available for record btrace target")); | |
1458 | ||
e7802207 TT |
1459 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1460 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1461 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1462 | throw_error (NOT_AVAILABLE_ERROR, | |
1463 | _("can't compute CFA for this frame: " | |
1464 | "required registers or memory are unavailable")); | |
14aba1ac JB |
1465 | |
1466 | if (get_frame_id (this_frame).stack_status != FID_STACK_VALID) | |
1467 | throw_error (NOT_AVAILABLE_ERROR, | |
1468 | _("can't compute CFA for this frame: " | |
1469 | "frame base not available")); | |
1470 | ||
e7802207 TT |
1471 | return get_frame_base (this_frame); |
1472 | } | |
cfc14b3a | 1473 | \f |
924d79e2 TT |
1474 | const struct objfile_key<dwarf2_fde_table, |
1475 | gdb::noop_deleter<dwarf2_fde_table>> | |
1476 | dwarf2_frame_objfile_data; | |
0d0e1a63 | 1477 | |
cfc14b3a MK |
1478 | \f |
1479 | ||
1480 | /* Pointer encoding helper functions. */ | |
1481 | ||
1482 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1483 | technical reasons, it encodes addresses in its FDE's in a different | |
1484 | way. Several "pointer encodings" are supported. The encoding | |
1485 | that's used for a particular FDE is determined by the 'R' | |
1486 | augmentation in the associated CIE. The argument of this | |
1487 | augmentation is a single byte. | |
1488 | ||
1489 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1490 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1491 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1492 | address should be interpreted (absolute, relative to the current | |
1493 | position in the FDE, ...). Bit 7, indicates that the address | |
1494 | should be dereferenced. */ | |
1495 | ||
852483bc | 1496 | static gdb_byte |
cfc14b3a MK |
1497 | encoding_for_size (unsigned int size) |
1498 | { | |
1499 | switch (size) | |
1500 | { | |
1501 | case 2: | |
1502 | return DW_EH_PE_udata2; | |
1503 | case 4: | |
1504 | return DW_EH_PE_udata4; | |
1505 | case 8: | |
1506 | return DW_EH_PE_udata8; | |
1507 | default: | |
e2e0b3e5 | 1508 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1509 | } |
1510 | } | |
1511 | ||
cfc14b3a | 1512 | static CORE_ADDR |
852483bc | 1513 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1514 | int ptr_len, const gdb_byte *buf, |
1515 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1516 | CORE_ADDR func_base) |
cfc14b3a | 1517 | { |
68f6cf99 | 1518 | ptrdiff_t offset; |
cfc14b3a MK |
1519 | CORE_ADDR base; |
1520 | ||
1521 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1522 | FDE's. */ | |
1523 | if (encoding & DW_EH_PE_indirect) | |
1524 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1525 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1526 | |
68f6cf99 MK |
1527 | *bytes_read_ptr = 0; |
1528 | ||
cfc14b3a MK |
1529 | switch (encoding & 0x70) |
1530 | { | |
1531 | case DW_EH_PE_absptr: | |
1532 | base = 0; | |
1533 | break; | |
1534 | case DW_EH_PE_pcrel: | |
fd361982 | 1535 | base = bfd_section_vma (unit->dwarf_frame_section); |
852483bc | 1536 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1537 | break; |
0912c7f2 MK |
1538 | case DW_EH_PE_datarel: |
1539 | base = unit->dbase; | |
1540 | break; | |
0fd85043 CV |
1541 | case DW_EH_PE_textrel: |
1542 | base = unit->tbase; | |
1543 | break; | |
03ac2a74 | 1544 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1545 | base = func_base; |
03ac2a74 | 1546 | break; |
68f6cf99 MK |
1547 | case DW_EH_PE_aligned: |
1548 | base = 0; | |
852483bc | 1549 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1550 | if ((offset % ptr_len) != 0) |
1551 | { | |
1552 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1553 | buf += *bytes_read_ptr; | |
1554 | } | |
1555 | break; | |
cfc14b3a | 1556 | default: |
3e43a32a MS |
1557 | internal_error (__FILE__, __LINE__, |
1558 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1559 | } |
1560 | ||
b04de778 | 1561 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1562 | { |
1563 | encoding |= encoding_for_size (ptr_len); | |
1564 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1565 | encoding |= DW_EH_PE_signed; | |
1566 | } | |
cfc14b3a MK |
1567 | |
1568 | switch (encoding & 0x0f) | |
1569 | { | |
a81b10ae MK |
1570 | case DW_EH_PE_uleb128: |
1571 | { | |
9fccedf7 | 1572 | uint64_t value; |
0d45f56e | 1573 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1574 | |
f664829e | 1575 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1576 | return base + value; |
1577 | } | |
cfc14b3a | 1578 | case DW_EH_PE_udata2: |
68f6cf99 | 1579 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1580 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1581 | case DW_EH_PE_udata4: | |
68f6cf99 | 1582 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1583 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1584 | case DW_EH_PE_udata8: | |
68f6cf99 | 1585 | *bytes_read_ptr += 8; |
cfc14b3a | 1586 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1587 | case DW_EH_PE_sleb128: |
1588 | { | |
9fccedf7 | 1589 | int64_t value; |
0d45f56e | 1590 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1591 | |
f664829e | 1592 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1593 | return base + value; |
1594 | } | |
cfc14b3a | 1595 | case DW_EH_PE_sdata2: |
68f6cf99 | 1596 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1597 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1598 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1599 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1600 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1601 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1602 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1603 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1604 | default: | |
3e43a32a MS |
1605 | internal_error (__FILE__, __LINE__, |
1606 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1607 | } |
1608 | } | |
1609 | \f | |
1610 | ||
b01c8410 PP |
1611 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ |
1612 | static struct dwarf2_cie * | |
93878f47 | 1613 | find_cie (const dwarf2_cie_table &cie_table, ULONGEST cie_pointer) |
b01c8410 | 1614 | { |
93878f47 TT |
1615 | auto iter = cie_table.find (cie_pointer); |
1616 | if (iter != cie_table.end ()) | |
1617 | return iter->second; | |
cfc14b3a MK |
1618 | return NULL; |
1619 | } | |
1620 | ||
35e65c49 CB |
1621 | static inline int |
1622 | bsearch_fde_cmp (const dwarf2_fde *fde, CORE_ADDR seek_pc) | |
b01c8410 | 1623 | { |
35e65c49 | 1624 | if (fde->initial_location + fde->address_range <= seek_pc) |
b01c8410 | 1625 | return -1; |
35e65c49 | 1626 | if (fde->initial_location <= seek_pc) |
b01c8410 PP |
1627 | return 0; |
1628 | return 1; | |
cfc14b3a MK |
1629 | } |
1630 | ||
1631 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
85102364 | 1632 | initial location associated with it into *PC. */ |
cfc14b3a MK |
1633 | |
1634 | static struct dwarf2_fde * | |
ac56253d | 1635 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a | 1636 | { |
2030c079 | 1637 | for (objfile *objfile : current_program_space->objfiles ()) |
cfc14b3a | 1638 | { |
b01c8410 | 1639 | struct dwarf2_fde_table *fde_table; |
cfc14b3a | 1640 | CORE_ADDR offset; |
b01c8410 | 1641 | CORE_ADDR seek_pc; |
cfc14b3a | 1642 | |
924d79e2 | 1643 | fde_table = dwarf2_frame_objfile_data.get (objfile); |
b01c8410 | 1644 | if (fde_table == NULL) |
be391dca TT |
1645 | { |
1646 | dwarf2_build_frame_info (objfile); | |
924d79e2 | 1647 | fde_table = dwarf2_frame_objfile_data.get (objfile); |
be391dca TT |
1648 | } |
1649 | gdb_assert (fde_table != NULL); | |
1650 | ||
1651 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1652 | continue; |
1653 | ||
6a053cb1 | 1654 | gdb_assert (!objfile->section_offsets.empty ()); |
b3b3bada | 1655 | offset = objfile->text_section_offset (); |
4ae9ee8e | 1656 | |
b01c8410 PP |
1657 | gdb_assert (fde_table->num_entries > 0); |
1658 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1659 | continue; | |
1660 | ||
1661 | seek_pc = *pc - offset; | |
35e65c49 CB |
1662 | auto end = fde_table->entries + fde_table->num_entries; |
1663 | auto it = gdb::binary_search (fde_table->entries, end, seek_pc, bsearch_fde_cmp); | |
1664 | if (it != end) | |
b01c8410 | 1665 | { |
35e65c49 | 1666 | *pc = (*it)->initial_location + offset; |
ac56253d TT |
1667 | if (out_offset) |
1668 | *out_offset = offset; | |
35e65c49 | 1669 | return *it; |
b01c8410 | 1670 | } |
cfc14b3a | 1671 | } |
cfc14b3a MK |
1672 | return NULL; |
1673 | } | |
1674 | ||
b01c8410 | 1675 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1676 | static void |
b01c8410 | 1677 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1678 | { |
b01c8410 PP |
1679 | if (fde->address_range == 0) |
1680 | /* Discard useless FDEs. */ | |
1681 | return; | |
1682 | ||
1683 | fde_table->num_entries += 1; | |
224c3ddb SM |
1684 | fde_table->entries = XRESIZEVEC (struct dwarf2_fde *, fde_table->entries, |
1685 | fde_table->num_entries); | |
b01c8410 | 1686 | fde_table->entries[fde_table->num_entries - 1] = fde; |
cfc14b3a MK |
1687 | } |
1688 | ||
cfc14b3a | 1689 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1690 | |
8bd90839 FM |
1691 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1692 | or any of them. */ | |
1693 | ||
1694 | enum eh_frame_type | |
1695 | { | |
1696 | EH_CIE_TYPE_ID = 1 << 0, | |
1697 | EH_FDE_TYPE_ID = 1 << 1, | |
1698 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1699 | }; | |
1700 | ||
f664829e DE |
1701 | static const gdb_byte *decode_frame_entry (struct comp_unit *unit, |
1702 | const gdb_byte *start, | |
1703 | int eh_frame_p, | |
93878f47 | 1704 | dwarf2_cie_table &cie_table, |
f664829e DE |
1705 | struct dwarf2_fde_table *fde_table, |
1706 | enum eh_frame_type entry_type); | |
8bd90839 FM |
1707 | |
1708 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1709 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1710 | |
f664829e DE |
1711 | static const gdb_byte * |
1712 | decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, | |
1713 | int eh_frame_p, | |
93878f47 | 1714 | dwarf2_cie_table &cie_table, |
8bd90839 FM |
1715 | struct dwarf2_fde_table *fde_table, |
1716 | enum eh_frame_type entry_type) | |
cfc14b3a | 1717 | { |
5e2b427d | 1718 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
f664829e | 1719 | const gdb_byte *buf, *end; |
723adb65 | 1720 | ULONGEST length; |
cfc14b3a | 1721 | unsigned int bytes_read; |
6896c0c7 RH |
1722 | int dwarf64_p; |
1723 | ULONGEST cie_id; | |
cfc14b3a | 1724 | ULONGEST cie_pointer; |
9fccedf7 DE |
1725 | int64_t sleb128; |
1726 | uint64_t uleb128; | |
cfc14b3a | 1727 | |
6896c0c7 | 1728 | buf = start; |
4075cb26 | 1729 | length = read_initial_length (unit->abfd, buf, &bytes_read, false); |
cfc14b3a | 1730 | buf += bytes_read; |
723adb65 | 1731 | end = buf + (size_t) length; |
6896c0c7 | 1732 | |
cfc14b3a MK |
1733 | if (length == 0) |
1734 | return end; | |
1735 | ||
723adb65 SL |
1736 | /* Are we still within the section? */ |
1737 | if (end <= buf || end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1738 | return NULL; | |
1739 | ||
6896c0c7 RH |
1740 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1741 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1742 | |
6896c0c7 | 1743 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1744 | if (eh_frame_p) |
1745 | cie_id = 0; | |
1746 | else if (dwarf64_p) | |
1747 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1748 | else |
1749 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1750 | |
1751 | if (dwarf64_p) | |
1752 | { | |
1753 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1754 | buf += 8; | |
1755 | } | |
1756 | else | |
1757 | { | |
1758 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1759 | buf += 4; | |
1760 | } | |
1761 | ||
1762 | if (cie_pointer == cie_id) | |
1763 | { | |
1764 | /* This is a CIE. */ | |
1765 | struct dwarf2_cie *cie; | |
1766 | char *augmentation; | |
28ba0b33 | 1767 | unsigned int cie_version; |
cfc14b3a | 1768 | |
8bd90839 FM |
1769 | /* Check that a CIE was expected. */ |
1770 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1771 | error (_("Found a CIE when not expecting it.")); | |
1772 | ||
cfc14b3a MK |
1773 | /* Record the offset into the .debug_frame section of this CIE. */ |
1774 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1775 | ||
1776 | /* Check whether we've already read it. */ | |
b01c8410 | 1777 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1778 | return end; |
1779 | ||
8d749320 | 1780 | cie = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_cie); |
cfc14b3a MK |
1781 | cie->initial_instructions = NULL; |
1782 | cie->cie_pointer = cie_pointer; | |
1783 | ||
1784 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1785 | depends on the target address size. */ |
1786 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1787 | |
56c987f6 AO |
1788 | /* We'll determine the final value later, but we need to |
1789 | initialize it conservatively. */ | |
1790 | cie->signal_frame = 0; | |
1791 | ||
cfc14b3a | 1792 | /* Check version number. */ |
28ba0b33 | 1793 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1794 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1795 | return NULL; |
303b6f5d | 1796 | cie->version = cie_version; |
cfc14b3a MK |
1797 | buf += 1; |
1798 | ||
1799 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1800 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1801 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1802 | |
303b6f5d DJ |
1803 | /* Ignore armcc augmentations. We only use them for quirks, |
1804 | and that doesn't happen until later. */ | |
61012eef | 1805 | if (startswith (augmentation, "armcc")) |
303b6f5d DJ |
1806 | augmentation += strlen (augmentation); |
1807 | ||
cfc14b3a MK |
1808 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1809 | following the augmentation string, so it must be handled | |
1810 | first. */ | |
1811 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1812 | { | |
1813 | /* Skip. */ | |
5e2b427d | 1814 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1815 | augmentation += 2; |
1816 | } | |
1817 | ||
2dc7f7b3 TT |
1818 | if (cie->version >= 4) |
1819 | { | |
1820 | /* FIXME: check that this is the same as from the CU header. */ | |
1821 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1822 | ++buf; | |
1823 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1824 | ++buf; | |
1825 | } | |
1826 | else | |
1827 | { | |
8da614df | 1828 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1829 | cie->segment_size = 0; |
1830 | } | |
8da614df CV |
1831 | /* Address values in .eh_frame sections are defined to have the |
1832 | target's pointer size. Watchout: This breaks frame info for | |
1833 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1834 | section exists as well. */ |
8da614df CV |
1835 | if (eh_frame_p) |
1836 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1837 | else | |
1838 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1839 | |
f664829e DE |
1840 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1841 | if (buf == NULL) | |
1842 | return NULL; | |
1843 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1844 | |
f664829e DE |
1845 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1846 | if (buf == NULL) | |
1847 | return NULL; | |
1848 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1849 | |
28ba0b33 PB |
1850 | if (cie_version == 1) |
1851 | { | |
1852 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1853 | ++buf; |
28ba0b33 PB |
1854 | } |
1855 | else | |
f664829e DE |
1856 | { |
1857 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1858 | if (buf == NULL) | |
1859 | return NULL; | |
1860 | cie->return_address_register = uleb128; | |
1861 | } | |
1862 | ||
4fc771b8 | 1863 | cie->return_address_register |
5e2b427d | 1864 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1865 | cie->return_address_register, |
1866 | eh_frame_p); | |
4bf8967c | 1867 | |
7131cb6e RH |
1868 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1869 | if (cie->saw_z_augmentation) | |
cfc14b3a | 1870 | { |
b926417a | 1871 | uint64_t uleb_length; |
cfc14b3a | 1872 | |
b926417a | 1873 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e | 1874 | if (buf == NULL) |
6896c0c7 | 1875 | return NULL; |
b926417a | 1876 | cie->initial_instructions = buf + uleb_length; |
cfc14b3a MK |
1877 | augmentation++; |
1878 | } | |
1879 | ||
1880 | while (*augmentation) | |
1881 | { | |
1882 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1883 | if (*augmentation == 'L') | |
1884 | { | |
1885 | /* Skip. */ | |
1886 | buf++; | |
1887 | augmentation++; | |
1888 | } | |
1889 | ||
1890 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1891 | else if (*augmentation == 'R') | |
1892 | { | |
1893 | cie->encoding = *buf++; | |
1894 | augmentation++; | |
1895 | } | |
1896 | ||
1897 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1898 | else if (*augmentation == 'P') | |
1899 | { | |
1234d960 | 1900 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1901 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1902 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1903 | buf, &bytes_read, 0); |
f724bf08 | 1904 | buf += bytes_read; |
cfc14b3a MK |
1905 | augmentation++; |
1906 | } | |
1907 | ||
56c987f6 AO |
1908 | /* "S" indicates a signal frame, such that the return |
1909 | address must not be decremented to locate the call frame | |
1910 | info for the previous frame; it might even be the first | |
1911 | instruction of a function, so decrementing it would take | |
1912 | us to a different function. */ | |
1913 | else if (*augmentation == 'S') | |
1914 | { | |
1915 | cie->signal_frame = 1; | |
1916 | augmentation++; | |
1917 | } | |
1918 | ||
3e9a2e52 DJ |
1919 | /* Otherwise we have an unknown augmentation. Assume that either |
1920 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1921 | else |
1922 | { | |
3e9a2e52 DJ |
1923 | if (cie->initial_instructions) |
1924 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1925 | break; |
1926 | } | |
1927 | } | |
1928 | ||
1929 | cie->initial_instructions = buf; | |
1930 | cie->end = end; | |
b01c8410 | 1931 | cie->unit = unit; |
cfc14b3a | 1932 | |
93878f47 | 1933 | cie_table[cie->cie_pointer] = cie; |
cfc14b3a MK |
1934 | } |
1935 | else | |
1936 | { | |
1937 | /* This is a FDE. */ | |
1938 | struct dwarf2_fde *fde; | |
3e29f34a | 1939 | CORE_ADDR addr; |
cfc14b3a | 1940 | |
8bd90839 FM |
1941 | /* Check that an FDE was expected. */ |
1942 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
1943 | error (_("Found an FDE when not expecting it.")); | |
1944 | ||
6896c0c7 RH |
1945 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1946 | address within the FDE where the CIE pointer is stored and the | |
1947 | address of the CIE. Convert it to an offset into the .eh_frame | |
1948 | section. */ | |
cfc14b3a MK |
1949 | if (eh_frame_p) |
1950 | { | |
cfc14b3a MK |
1951 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1952 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1953 | } | |
1954 | ||
6896c0c7 RH |
1955 | /* In either case, validate the result is still within the section. */ |
1956 | if (cie_pointer >= unit->dwarf_frame_size) | |
1957 | return NULL; | |
1958 | ||
8d749320 | 1959 | fde = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_fde); |
b01c8410 | 1960 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
1961 | if (fde->cie == NULL) |
1962 | { | |
1963 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
1964 | eh_frame_p, cie_table, fde_table, |
1965 | EH_CIE_TYPE_ID); | |
b01c8410 | 1966 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
1967 | } |
1968 | ||
1969 | gdb_assert (fde->cie != NULL); | |
1970 | ||
3e29f34a MR |
1971 | addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
1972 | buf, &bytes_read, 0); | |
1973 | fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); | |
cfc14b3a MK |
1974 | buf += bytes_read; |
1975 | ||
1976 | fde->address_range = | |
ae0d2f24 | 1977 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 1978 | fde->cie->ptr_size, buf, &bytes_read, 0); |
3e29f34a MR |
1979 | addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); |
1980 | fde->address_range = addr - fde->initial_location; | |
cfc14b3a MK |
1981 | buf += bytes_read; |
1982 | ||
7131cb6e RH |
1983 | /* A 'z' augmentation in the CIE implies the presence of an |
1984 | augmentation field in the FDE as well. The only thing known | |
1985 | to be in here at present is the LSDA entry for EH. So we | |
1986 | can skip the whole thing. */ | |
1987 | if (fde->cie->saw_z_augmentation) | |
1988 | { | |
b926417a | 1989 | uint64_t uleb_length; |
7131cb6e | 1990 | |
b926417a | 1991 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e DE |
1992 | if (buf == NULL) |
1993 | return NULL; | |
b926417a | 1994 | buf += uleb_length; |
6896c0c7 RH |
1995 | if (buf > end) |
1996 | return NULL; | |
7131cb6e RH |
1997 | } |
1998 | ||
cfc14b3a MK |
1999 | fde->instructions = buf; |
2000 | fde->end = end; | |
2001 | ||
4bf8967c AS |
2002 | fde->eh_frame_p = eh_frame_p; |
2003 | ||
b01c8410 | 2004 | add_fde (fde_table, fde); |
cfc14b3a MK |
2005 | } |
2006 | ||
2007 | return end; | |
2008 | } | |
6896c0c7 | 2009 | |
8bd90839 FM |
2010 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2011 | expect an FDE or a CIE. */ | |
2012 | ||
f664829e DE |
2013 | static const gdb_byte * |
2014 | decode_frame_entry (struct comp_unit *unit, const gdb_byte *start, | |
2015 | int eh_frame_p, | |
93878f47 | 2016 | dwarf2_cie_table &cie_table, |
8bd90839 FM |
2017 | struct dwarf2_fde_table *fde_table, |
2018 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2019 | { |
2020 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2021 | const gdb_byte *ret; |
6896c0c7 RH |
2022 | ptrdiff_t start_offset; |
2023 | ||
2024 | while (1) | |
2025 | { | |
b01c8410 | 2026 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
8bd90839 | 2027 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2028 | if (ret != NULL) |
2029 | break; | |
2030 | ||
2031 | /* We have corrupt input data of some form. */ | |
2032 | ||
2033 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2034 | and mismatches wrt padding and alignment of debug sections. */ | |
2035 | /* Note that there is no requirement in the standard for any | |
2036 | alignment at all in the frame unwind sections. Testing for | |
2037 | alignment before trying to interpret data would be incorrect. | |
2038 | ||
2039 | However, GCC traditionally arranged for frame sections to be | |
2040 | sized such that the FDE length and CIE fields happen to be | |
2041 | aligned (in theory, for performance). This, unfortunately, | |
2042 | was done with .align directives, which had the side effect of | |
2043 | forcing the section to be aligned by the linker. | |
2044 | ||
2045 | This becomes a problem when you have some other producer that | |
2046 | creates frame sections that are not as strictly aligned. That | |
2047 | produces a hole in the frame info that gets filled by the | |
2048 | linker with zeros. | |
2049 | ||
2050 | The GCC behaviour is arguably a bug, but it's effectively now | |
2051 | part of the ABI, so we're now stuck with it, at least at the | |
2052 | object file level. A smart linker may decide, in the process | |
2053 | of compressing duplicate CIE information, that it can rewrite | |
2054 | the entire output section without this extra padding. */ | |
2055 | ||
2056 | start_offset = start - unit->dwarf_frame_buffer; | |
2057 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2058 | { | |
2059 | start += 4 - (start_offset & 3); | |
2060 | workaround = ALIGN4; | |
2061 | continue; | |
2062 | } | |
2063 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2064 | { | |
2065 | start += 8 - (start_offset & 7); | |
2066 | workaround = ALIGN8; | |
2067 | continue; | |
2068 | } | |
2069 | ||
2070 | /* Nothing left to try. Arrange to return as if we've consumed | |
2071 | the entire input section. Hopefully we'll get valid info from | |
2072 | the other of .debug_frame/.eh_frame. */ | |
2073 | workaround = FAIL; | |
2074 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2075 | break; | |
2076 | } | |
2077 | ||
2078 | switch (workaround) | |
2079 | { | |
2080 | case NONE: | |
2081 | break; | |
2082 | ||
2083 | case ALIGN4: | |
b98664d3 | 2084 | complaint (_("\ |
3e43a32a | 2085 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
2086 | unit->dwarf_frame_section->owner->filename, |
2087 | unit->dwarf_frame_section->name); | |
2088 | break; | |
2089 | ||
2090 | case ALIGN8: | |
b98664d3 | 2091 | complaint (_("\ |
3e43a32a | 2092 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
2093 | unit->dwarf_frame_section->owner->filename, |
2094 | unit->dwarf_frame_section->name); | |
2095 | break; | |
2096 | ||
2097 | default: | |
b98664d3 | 2098 | complaint (_("Corrupt data in %s:%s"), |
6896c0c7 RH |
2099 | unit->dwarf_frame_section->owner->filename, |
2100 | unit->dwarf_frame_section->name); | |
2101 | break; | |
2102 | } | |
2103 | ||
2104 | return ret; | |
2105 | } | |
cfc14b3a | 2106 | \f |
39ef2f62 CB |
2107 | static bool |
2108 | fde_is_less_than (const dwarf2_fde *aa, const dwarf2_fde *bb) | |
b01c8410 | 2109 | { |
b01c8410 | 2110 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2111 | { |
2112 | if (aa->address_range != bb->address_range | |
2113 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2114 | /* Linker bug, e.g. gold/10400. | |
2115 | Work around it by keeping stable sort order. */ | |
39ef2f62 | 2116 | return aa < bb; |
e5af178f PP |
2117 | else |
2118 | /* Put eh_frame entries after debug_frame ones. */ | |
39ef2f62 | 2119 | return aa->eh_frame_p < bb->eh_frame_p; |
e5af178f | 2120 | } |
b01c8410 | 2121 | |
39ef2f62 | 2122 | return aa->initial_location < bb->initial_location; |
b01c8410 PP |
2123 | } |
2124 | ||
cfc14b3a MK |
2125 | void |
2126 | dwarf2_build_frame_info (struct objfile *objfile) | |
2127 | { | |
ae0d2f24 | 2128 | struct comp_unit *unit; |
f664829e | 2129 | const gdb_byte *frame_ptr; |
93878f47 | 2130 | dwarf2_cie_table cie_table; |
b01c8410 | 2131 | struct dwarf2_fde_table fde_table; |
be391dca | 2132 | struct dwarf2_fde_table *fde_table2; |
b01c8410 | 2133 | |
b01c8410 PP |
2134 | fde_table.num_entries = 0; |
2135 | fde_table.entries = NULL; | |
cfc14b3a MK |
2136 | |
2137 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
e39db4db | 2138 | unit = XOBNEW (&objfile->objfile_obstack, comp_unit); |
ae0d2f24 UW |
2139 | unit->abfd = objfile->obfd; |
2140 | unit->objfile = objfile; | |
2141 | unit->dbase = 0; | |
2142 | unit->tbase = 0; | |
cfc14b3a | 2143 | |
d40102a1 | 2144 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2145 | { |
d40102a1 JB |
2146 | /* Do not read .eh_frame from separate file as they must be also |
2147 | present in the main file. */ | |
2148 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, | |
2149 | &unit->dwarf_frame_section, | |
2150 | &unit->dwarf_frame_buffer, | |
2151 | &unit->dwarf_frame_size); | |
2152 | if (unit->dwarf_frame_size) | |
b01c8410 | 2153 | { |
d40102a1 JB |
2154 | asection *got, *txt; |
2155 | ||
2156 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2157 | that is used for the i386/amd64 target, which currently is | |
2158 | the only target in GCC that supports/uses the | |
2159 | DW_EH_PE_datarel encoding. */ | |
2160 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2161 | if (got) | |
2162 | unit->dbase = got->vma; | |
2163 | ||
2164 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2165 | so far. */ | |
2166 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2167 | if (txt) | |
2168 | unit->tbase = txt->vma; | |
2169 | ||
a70b8144 | 2170 | try |
8bd90839 FM |
2171 | { |
2172 | frame_ptr = unit->dwarf_frame_buffer; | |
2173 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2174 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, | |
93878f47 | 2175 | cie_table, &fde_table, |
8bd90839 FM |
2176 | EH_CIE_OR_FDE_TYPE_ID); |
2177 | } | |
2178 | ||
230d2906 | 2179 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2180 | { |
2181 | warning (_("skipping .eh_frame info of %s: %s"), | |
3d6e9d23 | 2182 | objfile_name (objfile), e.what ()); |
8bd90839 FM |
2183 | |
2184 | if (fde_table.num_entries != 0) | |
2185 | { | |
2186 | xfree (fde_table.entries); | |
2187 | fde_table.entries = NULL; | |
2188 | fde_table.num_entries = 0; | |
2189 | } | |
93878f47 | 2190 | /* The cie_table is discarded below. */ |
8bd90839 | 2191 | } |
d40102a1 | 2192 | |
93878f47 | 2193 | cie_table.clear (); |
b01c8410 | 2194 | } |
cfc14b3a MK |
2195 | } |
2196 | ||
3017a003 | 2197 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dce234bc PP |
2198 | &unit->dwarf_frame_section, |
2199 | &unit->dwarf_frame_buffer, | |
2200 | &unit->dwarf_frame_size); | |
2201 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2202 | { |
8bd90839 FM |
2203 | int num_old_fde_entries = fde_table.num_entries; |
2204 | ||
a70b8144 | 2205 | try |
8bd90839 FM |
2206 | { |
2207 | frame_ptr = unit->dwarf_frame_buffer; | |
2208 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2209 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, | |
93878f47 | 2210 | cie_table, &fde_table, |
8bd90839 FM |
2211 | EH_CIE_OR_FDE_TYPE_ID); |
2212 | } | |
230d2906 | 2213 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2214 | { |
2215 | warning (_("skipping .debug_frame info of %s: %s"), | |
3d6e9d23 | 2216 | objfile_name (objfile), e.what ()); |
8bd90839 FM |
2217 | |
2218 | if (fde_table.num_entries != 0) | |
2219 | { | |
2220 | fde_table.num_entries = num_old_fde_entries; | |
2221 | if (num_old_fde_entries == 0) | |
2222 | { | |
2223 | xfree (fde_table.entries); | |
2224 | fde_table.entries = NULL; | |
2225 | } | |
2226 | else | |
2227 | { | |
224c3ddb SM |
2228 | fde_table.entries |
2229 | = XRESIZEVEC (struct dwarf2_fde *, fde_table.entries, | |
2230 | fde_table.num_entries); | |
8bd90839 FM |
2231 | } |
2232 | } | |
2233 | fde_table.num_entries = num_old_fde_entries; | |
8bd90839 | 2234 | } |
b01c8410 PP |
2235 | } |
2236 | ||
be391dca | 2237 | /* Copy fde_table to obstack: it is needed at runtime. */ |
8d749320 | 2238 | fde_table2 = XOBNEW (&objfile->objfile_obstack, struct dwarf2_fde_table); |
be391dca TT |
2239 | |
2240 | if (fde_table.num_entries == 0) | |
2241 | { | |
2242 | fde_table2->entries = NULL; | |
2243 | fde_table2->num_entries = 0; | |
2244 | } | |
2245 | else | |
b01c8410 | 2246 | { |
875cdfbb PA |
2247 | struct dwarf2_fde *fde_prev = NULL; |
2248 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2249 | int i; | |
b01c8410 PP |
2250 | |
2251 | /* Prepare FDE table for lookups. */ | |
39ef2f62 CB |
2252 | std::sort (fde_table.entries, fde_table.entries + fde_table.num_entries, |
2253 | fde_is_less_than); | |
b01c8410 | 2254 | |
875cdfbb PA |
2255 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2256 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2257 | ranges because there's no relocation there. It's (offset, | |
2258 | length), not (start, end). On targets where address zero is | |
2259 | just another valid address this can be a problem, since the | |
2260 | FDEs appear to be non-empty in the output --- we could pick | |
2261 | out the wrong FDE. To work around this, when overlaps are | |
2262 | detected, we prefer FDEs that do not start at zero. | |
2263 | ||
2264 | Start by finding the first FDE with non-zero start. Below | |
2265 | we'll discard all FDEs that start at zero and overlap this | |
2266 | one. */ | |
2267 | for (i = 0; i < fde_table.num_entries; i++) | |
2268 | { | |
2269 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2270 | |
875cdfbb PA |
2271 | if (fde->initial_location != 0) |
2272 | { | |
2273 | first_non_zero_fde = fde; | |
2274 | break; | |
2275 | } | |
2276 | } | |
2277 | ||
2278 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2279 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2280 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2281 | fde_table2->num_entries = 0; |
875cdfbb PA |
2282 | for (i = 0; i < fde_table.num_entries; i++) |
2283 | { | |
2284 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2285 | ||
2286 | if (fde->initial_location == 0 | |
2287 | && first_non_zero_fde != NULL | |
2288 | && (first_non_zero_fde->initial_location | |
2289 | < fde->initial_location + fde->address_range)) | |
2290 | continue; | |
2291 | ||
2292 | if (fde_prev != NULL | |
2293 | && fde_prev->initial_location == fde->initial_location) | |
2294 | continue; | |
2295 | ||
2296 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2297 | sizeof (fde_table.entries[0])); | |
2298 | ++fde_table2->num_entries; | |
2299 | fde_prev = fde; | |
2300 | } | |
224c3ddb SM |
2301 | fde_table2->entries |
2302 | = (struct dwarf2_fde **) obstack_finish (&objfile->objfile_obstack); | |
b01c8410 PP |
2303 | |
2304 | /* Discard the original fde_table. */ | |
2305 | xfree (fde_table.entries); | |
cfc14b3a | 2306 | } |
be391dca | 2307 | |
924d79e2 | 2308 | dwarf2_frame_objfile_data.set (objfile, fde_table2); |
cfc14b3a | 2309 | } |
0d0e1a63 | 2310 | |
3c3bb058 AB |
2311 | /* Handle 'maintenance show dwarf unwinders'. */ |
2312 | ||
2313 | static void | |
2314 | show_dwarf_unwinders_enabled_p (struct ui_file *file, int from_tty, | |
2315 | struct cmd_list_element *c, | |
2316 | const char *value) | |
2317 | { | |
2318 | fprintf_filtered (file, | |
2319 | _("The DWARF stack unwinders are currently %s.\n"), | |
2320 | value); | |
2321 | } | |
2322 | ||
6c265988 | 2323 | void _initialize_dwarf2_frame (); |
0d0e1a63 | 2324 | void |
6c265988 | 2325 | _initialize_dwarf2_frame () |
0d0e1a63 | 2326 | { |
030f20e1 | 2327 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
1c90d9f0 | 2328 | |
3c3bb058 AB |
2329 | add_setshow_boolean_cmd ("unwinders", class_obscure, |
2330 | &dwarf2_frame_unwinders_enabled_p , _("\ | |
2331 | Set whether the DWARF stack frame unwinders are used."), _("\ | |
2332 | Show whether the DWARF stack frame unwinders are used."), _("\ | |
2333 | When enabled the DWARF stack frame unwinders can be used for architectures\n\ | |
2334 | that support the DWARF unwinders. Enabling the DWARF unwinders for an\n\ | |
2335 | architecture that doesn't support them will have no effect."), | |
2336 | NULL, | |
2337 | show_dwarf_unwinders_enabled_p, | |
2338 | &set_dwarf_cmdlist, | |
2339 | &show_dwarf_cmdlist); | |
2340 | ||
1c90d9f0 | 2341 | #if GDB_SELF_TEST |
1526853e SM |
2342 | selftests::register_test_foreach_arch ("execute_cfa_program", |
2343 | selftests::execute_cfa_program_test); | |
1c90d9f0 | 2344 | #endif |
0d0e1a63 | 2345 | } |