Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
42a4f53d | 3 | Copyright (C) 2003-2019 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" | |
d55e5aa6 | 23 | #include "dwarf2expr.h" |
4de283e4 TT |
24 | #include "dwarf2.h" |
25 | #include "frame.h" | |
cfc14b3a MK |
26 | #include "frame-base.h" |
27 | #include "frame-unwind.h" | |
28 | #include "gdbcore.h" | |
29 | #include "gdbtypes.h" | |
4de283e4 | 30 | #include "symtab.h" |
cfc14b3a MK |
31 | #include "objfiles.h" |
32 | #include "regcache.h" | |
f2da6b3a | 33 | #include "value.h" |
4de283e4 | 34 | #include "record.h" |
cfc14b3a | 35 | |
4de283e4 TT |
36 | #include "complaints.h" |
37 | #include "dwarf2-frame.h" | |
38 | #include "dwarf2read.h" | |
39 | #include "ax.h" | |
40 | #include "dwarf2loc.h" | |
41 | #include "dwarf2-frame-tailcall.h" | |
1c90d9f0 | 42 | #if GDB_SELF_TEST |
268a13a5 | 43 | #include "gdbsupport/selftest.h" |
1c90d9f0 YQ |
44 | #include "selftest-arch.h" |
45 | #endif | |
cfc14b3a | 46 | |
ae0d2f24 UW |
47 | struct comp_unit; |
48 | ||
cfc14b3a MK |
49 | /* Call Frame Information (CFI). */ |
50 | ||
51 | /* Common Information Entry (CIE). */ | |
52 | ||
53 | struct dwarf2_cie | |
54 | { | |
ae0d2f24 UW |
55 | /* Computation Unit for this CIE. */ |
56 | struct comp_unit *unit; | |
57 | ||
cfc14b3a MK |
58 | /* Offset into the .debug_frame section where this CIE was found. |
59 | Used to identify this CIE. */ | |
60 | ULONGEST cie_pointer; | |
61 | ||
62 | /* Constant that is factored out of all advance location | |
63 | instructions. */ | |
64 | ULONGEST code_alignment_factor; | |
65 | ||
66 | /* Constants that is factored out of all offset instructions. */ | |
67 | LONGEST data_alignment_factor; | |
68 | ||
69 | /* Return address column. */ | |
70 | ULONGEST return_address_register; | |
71 | ||
72 | /* Instruction sequence to initialize a register set. */ | |
f664829e DE |
73 | const gdb_byte *initial_instructions; |
74 | const gdb_byte *end; | |
cfc14b3a | 75 | |
303b6f5d DJ |
76 | /* Saved augmentation, in case it's needed later. */ |
77 | char *augmentation; | |
78 | ||
cfc14b3a | 79 | /* Encoding of addresses. */ |
852483bc | 80 | gdb_byte encoding; |
cfc14b3a | 81 | |
ae0d2f24 UW |
82 | /* Target address size in bytes. */ |
83 | int addr_size; | |
84 | ||
0963b4bd | 85 | /* Target pointer size in bytes. */ |
8da614df CV |
86 | int ptr_size; |
87 | ||
7131cb6e RH |
88 | /* True if a 'z' augmentation existed. */ |
89 | unsigned char saw_z_augmentation; | |
90 | ||
56c987f6 AO |
91 | /* True if an 'S' augmentation existed. */ |
92 | unsigned char signal_frame; | |
93 | ||
303b6f5d DJ |
94 | /* The version recorded in the CIE. */ |
95 | unsigned char version; | |
2dc7f7b3 TT |
96 | |
97 | /* The segment size. */ | |
98 | unsigned char segment_size; | |
b01c8410 | 99 | }; |
303b6f5d | 100 | |
b01c8410 PP |
101 | struct dwarf2_cie_table |
102 | { | |
103 | int num_entries; | |
104 | struct dwarf2_cie **entries; | |
cfc14b3a MK |
105 | }; |
106 | ||
107 | /* Frame Description Entry (FDE). */ | |
108 | ||
109 | struct dwarf2_fde | |
110 | { | |
111 | /* CIE for this FDE. */ | |
112 | struct dwarf2_cie *cie; | |
113 | ||
114 | /* First location associated with this FDE. */ | |
115 | CORE_ADDR initial_location; | |
116 | ||
117 | /* Number of bytes of program instructions described by this FDE. */ | |
118 | CORE_ADDR address_range; | |
119 | ||
120 | /* Instruction sequence. */ | |
f664829e DE |
121 | const gdb_byte *instructions; |
122 | const gdb_byte *end; | |
cfc14b3a | 123 | |
4bf8967c AS |
124 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
125 | section. */ | |
126 | unsigned char eh_frame_p; | |
b01c8410 | 127 | }; |
4bf8967c | 128 | |
b01c8410 PP |
129 | struct dwarf2_fde_table |
130 | { | |
131 | int num_entries; | |
132 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
133 | }; |
134 | ||
ae0d2f24 UW |
135 | /* A minimal decoding of DWARF2 compilation units. We only decode |
136 | what's needed to get to the call frame information. */ | |
137 | ||
138 | struct comp_unit | |
139 | { | |
140 | /* Keep the bfd convenient. */ | |
141 | bfd *abfd; | |
142 | ||
143 | struct objfile *objfile; | |
144 | ||
ae0d2f24 | 145 | /* Pointer to the .debug_frame section loaded into memory. */ |
d521ce57 | 146 | const gdb_byte *dwarf_frame_buffer; |
ae0d2f24 UW |
147 | |
148 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 149 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
150 | |
151 | /* Pointer to the .debug_frame section. */ | |
152 | asection *dwarf_frame_section; | |
153 | ||
154 | /* Base for DW_EH_PE_datarel encodings. */ | |
155 | bfd_vma dbase; | |
156 | ||
157 | /* Base for DW_EH_PE_textrel encodings. */ | |
158 | bfd_vma tbase; | |
159 | }; | |
160 | ||
ac56253d TT |
161 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
162 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
163 | |
164 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
165 | int eh_frame_p); | |
ae0d2f24 UW |
166 | |
167 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 168 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
169 | unsigned int *bytes_read_ptr, |
170 | CORE_ADDR func_base); | |
cfc14b3a MK |
171 | \f |
172 | ||
3c3bb058 | 173 | /* See dwarf2-frame.h. */ |
491144b5 | 174 | bool dwarf2_frame_unwinders_enabled_p = true; |
3c3bb058 | 175 | |
cfc14b3a MK |
176 | /* Store the length the expression for the CFA in the `cfa_reg' field, |
177 | which is unused in that case. */ | |
178 | #define cfa_exp_len cfa_reg | |
179 | ||
afe37d6b YQ |
180 | dwarf2_frame_state::dwarf2_frame_state (CORE_ADDR pc_, struct dwarf2_cie *cie) |
181 | : pc (pc_), data_align (cie->data_alignment_factor), | |
182 | code_align (cie->code_alignment_factor), | |
183 | retaddr_column (cie->return_address_register) | |
cfc14b3a | 184 | { |
afe37d6b | 185 | } |
cfc14b3a MK |
186 | \f |
187 | ||
188 | /* Helper functions for execute_stack_op. */ | |
189 | ||
190 | static CORE_ADDR | |
192ca6d8 | 191 | read_addr_from_reg (struct frame_info *this_frame, int reg) |
cfc14b3a | 192 | { |
4a4e5149 | 193 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
0fde2c53 | 194 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); |
f2da6b3a | 195 | |
2ed3c037 | 196 | return address_from_register (regnum, this_frame); |
cfc14b3a MK |
197 | } |
198 | ||
a6a5a945 LM |
199 | /* Execute the required actions for both the DW_CFA_restore and |
200 | DW_CFA_restore_extended instructions. */ | |
201 | static void | |
202 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
203 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
204 | { | |
205 | ULONGEST reg; | |
206 | ||
a6a5a945 | 207 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); |
1c90d9f0 | 208 | fs->regs.alloc_regs (reg + 1); |
a6a5a945 LM |
209 | |
210 | /* Check if this register was explicitly initialized in the | |
211 | CIE initial instructions. If not, default the rule to | |
212 | UNSPECIFIED. */ | |
780942fc | 213 | if (reg < fs->initial.reg.size ()) |
a6a5a945 LM |
214 | fs->regs.reg[reg] = fs->initial.reg[reg]; |
215 | else | |
216 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
217 | ||
218 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
0fde2c53 DE |
219 | { |
220 | int regnum = dwarf_reg_to_regnum (gdbarch, reg); | |
221 | ||
b98664d3 | 222 | complaint (_("\ |
a6a5a945 | 223 | incomplete CFI data; DW_CFA_restore unspecified\n\ |
5af949e3 | 224 | register %s (#%d) at %s"), |
0fde2c53 DE |
225 | gdbarch_register_name (gdbarch, regnum), regnum, |
226 | paddress (gdbarch, fs->pc)); | |
227 | } | |
a6a5a945 LM |
228 | } |
229 | ||
192ca6d8 | 230 | class dwarf_expr_executor : public dwarf_expr_context |
9e8b7a03 | 231 | { |
192ca6d8 TT |
232 | public: |
233 | ||
234 | struct frame_info *this_frame; | |
235 | ||
632e107b | 236 | CORE_ADDR read_addr_from_reg (int reg) override |
192ca6d8 TT |
237 | { |
238 | return ::read_addr_from_reg (this_frame, reg); | |
239 | } | |
240 | ||
632e107b | 241 | struct value *get_reg_value (struct type *type, int reg) override |
192ca6d8 TT |
242 | { |
243 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
244 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, reg); | |
245 | ||
246 | return value_from_register (type, regnum, this_frame); | |
247 | } | |
248 | ||
632e107b | 249 | void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t len) override |
192ca6d8 TT |
250 | { |
251 | read_memory (addr, buf, len); | |
252 | } | |
befbff86 | 253 | |
632e107b | 254 | void get_frame_base (const gdb_byte **start, size_t *length) override |
befbff86 TT |
255 | { |
256 | invalid ("DW_OP_fbreg"); | |
257 | } | |
258 | ||
259 | void push_dwarf_reg_entry_value (enum call_site_parameter_kind kind, | |
260 | union call_site_parameter_u kind_u, | |
632e107b | 261 | int deref_size) override |
befbff86 | 262 | { |
216f72a1 | 263 | invalid ("DW_OP_entry_value"); |
befbff86 TT |
264 | } |
265 | ||
632e107b | 266 | CORE_ADDR get_object_address () override |
befbff86 TT |
267 | { |
268 | invalid ("DW_OP_push_object_address"); | |
269 | } | |
270 | ||
632e107b | 271 | CORE_ADDR get_frame_cfa () override |
befbff86 TT |
272 | { |
273 | invalid ("DW_OP_call_frame_cfa"); | |
274 | } | |
275 | ||
632e107b | 276 | CORE_ADDR get_tls_address (CORE_ADDR offset) override |
befbff86 TT |
277 | { |
278 | invalid ("DW_OP_form_tls_address"); | |
279 | } | |
280 | ||
632e107b | 281 | void dwarf_call (cu_offset die_offset) override |
befbff86 TT |
282 | { |
283 | invalid ("DW_OP_call*"); | |
284 | } | |
285 | ||
a6b786da KB |
286 | struct value *dwarf_variable_value (sect_offset sect_off) override |
287 | { | |
288 | invalid ("DW_OP_GNU_variable_value"); | |
289 | } | |
290 | ||
632e107b | 291 | CORE_ADDR get_addr_index (unsigned int index) override |
befbff86 | 292 | { |
336d760d | 293 | invalid ("DW_OP_addrx or DW_OP_GNU_addr_index"); |
befbff86 TT |
294 | } |
295 | ||
296 | private: | |
297 | ||
298 | void invalid (const char *op) ATTRIBUTE_NORETURN | |
299 | { | |
300 | error (_("%s is invalid in this context"), op); | |
301 | } | |
9e8b7a03 JK |
302 | }; |
303 | ||
cfc14b3a | 304 | static CORE_ADDR |
0d45f56e | 305 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
306 | CORE_ADDR offset, struct frame_info *this_frame, |
307 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a | 308 | { |
cfc14b3a MK |
309 | CORE_ADDR result; |
310 | ||
192ca6d8 | 311 | dwarf_expr_executor ctx; |
eb115069 | 312 | scoped_value_mark free_values; |
4a227398 | 313 | |
192ca6d8 | 314 | ctx.this_frame = this_frame; |
718b9626 TT |
315 | ctx.gdbarch = get_frame_arch (this_frame); |
316 | ctx.addr_size = addr_size; | |
317 | ctx.ref_addr_size = -1; | |
318 | ctx.offset = offset; | |
cfc14b3a | 319 | |
595d2e30 TT |
320 | ctx.push_address (initial, initial_in_stack_memory); |
321 | ctx.eval (exp, len); | |
cfc14b3a | 322 | |
718b9626 | 323 | if (ctx.location == DWARF_VALUE_MEMORY) |
595d2e30 | 324 | result = ctx.fetch_address (0); |
718b9626 | 325 | else if (ctx.location == DWARF_VALUE_REGISTER) |
192ca6d8 | 326 | result = ctx.read_addr_from_reg (value_as_long (ctx.fetch (0))); |
f2c7657e | 327 | else |
cec03d70 TT |
328 | { |
329 | /* This is actually invalid DWARF, but if we ever do run across | |
330 | it somehow, we might as well support it. So, instead, report | |
331 | it as unimplemented. */ | |
3e43a32a MS |
332 | error (_("\ |
333 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 334 | } |
cfc14b3a | 335 | |
cfc14b3a MK |
336 | return result; |
337 | } | |
338 | \f | |
339 | ||
111c6489 JK |
340 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
341 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
342 | execution has stopped, one can resume it on the next call. */ | |
343 | ||
344 | static const gdb_byte * | |
0d45f56e | 345 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff TT |
346 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
347 | CORE_ADDR pc, struct dwarf2_frame_state *fs) | |
cfc14b3a | 348 | { |
ae0d2f24 | 349 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 350 | unsigned int bytes_read; |
e17a4113 | 351 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
352 | |
353 | while (insn_ptr < insn_end && fs->pc <= pc) | |
354 | { | |
852483bc | 355 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
356 | uint64_t utmp, reg; |
357 | int64_t offset; | |
cfc14b3a MK |
358 | |
359 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
360 | fs->pc += (insn & 0x3f) * fs->code_align; | |
361 | else if ((insn & 0xc0) == DW_CFA_offset) | |
362 | { | |
363 | reg = insn & 0x3f; | |
4fc771b8 | 364 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 365 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 366 | offset = utmp * fs->data_align; |
1c90d9f0 | 367 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 368 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
369 | fs->regs.reg[reg].loc.offset = offset; |
370 | } | |
371 | else if ((insn & 0xc0) == DW_CFA_restore) | |
372 | { | |
cfc14b3a | 373 | reg = insn & 0x3f; |
a6a5a945 | 374 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
375 | } |
376 | else | |
377 | { | |
378 | switch (insn) | |
379 | { | |
380 | case DW_CFA_set_loc: | |
ae0d2f24 | 381 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 382 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
383 | &bytes_read, fde->initial_location); |
384 | /* Apply the objfile offset for relocatable objects. */ | |
385 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
386 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
387 | insn_ptr += bytes_read; |
388 | break; | |
389 | ||
390 | case DW_CFA_advance_loc1: | |
e17a4113 | 391 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
392 | fs->pc += utmp * fs->code_align; |
393 | insn_ptr++; | |
394 | break; | |
395 | case DW_CFA_advance_loc2: | |
e17a4113 | 396 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
397 | fs->pc += utmp * fs->code_align; |
398 | insn_ptr += 2; | |
399 | break; | |
400 | case DW_CFA_advance_loc4: | |
e17a4113 | 401 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
402 | fs->pc += utmp * fs->code_align; |
403 | insn_ptr += 4; | |
404 | break; | |
405 | ||
406 | case DW_CFA_offset_extended: | |
f664829e | 407 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 408 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 409 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a | 410 | offset = utmp * fs->data_align; |
1c90d9f0 | 411 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 412 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
413 | fs->regs.reg[reg].loc.offset = offset; |
414 | break; | |
415 | ||
416 | case DW_CFA_restore_extended: | |
f664829e | 417 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 418 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
419 | break; |
420 | ||
421 | case DW_CFA_undefined: | |
f664829e | 422 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 423 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 424 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 425 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
426 | break; |
427 | ||
428 | case DW_CFA_same_value: | |
f664829e | 429 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 430 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 431 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 432 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
433 | break; |
434 | ||
435 | case DW_CFA_register: | |
f664829e | 436 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 437 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 438 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 439 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
1c90d9f0 | 440 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 441 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
442 | fs->regs.reg[reg].loc.reg = utmp; |
443 | break; | |
444 | ||
445 | case DW_CFA_remember_state: | |
446 | { | |
447 | struct dwarf2_frame_state_reg_info *new_rs; | |
448 | ||
1c90d9f0 | 449 | new_rs = new dwarf2_frame_state_reg_info (fs->regs); |
cfc14b3a MK |
450 | fs->regs.prev = new_rs; |
451 | } | |
452 | break; | |
453 | ||
454 | case DW_CFA_restore_state: | |
455 | { | |
456 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
457 | ||
50ea7769 MK |
458 | if (old_rs == NULL) |
459 | { | |
b98664d3 | 460 | complaint (_("\ |
5af949e3 UW |
461 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
462 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
463 | } |
464 | else | |
1c90d9f0 | 465 | fs->regs = std::move (*old_rs); |
cfc14b3a MK |
466 | } |
467 | break; | |
468 | ||
469 | case DW_CFA_def_cfa: | |
f664829e DE |
470 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
471 | fs->regs.cfa_reg = reg; | |
472 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
473 | |
474 | if (fs->armcc_cfa_offsets_sf) | |
475 | utmp *= fs->data_align; | |
476 | ||
2fd481e1 PP |
477 | fs->regs.cfa_offset = utmp; |
478 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
479 | break; |
480 | ||
481 | case DW_CFA_def_cfa_register: | |
f664829e DE |
482 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
483 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 PP |
484 | eh_frame_p); |
485 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
486 | break; |
487 | ||
488 | case DW_CFA_def_cfa_offset: | |
f664829e | 489 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
490 | |
491 | if (fs->armcc_cfa_offsets_sf) | |
492 | utmp *= fs->data_align; | |
493 | ||
2fd481e1 | 494 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
495 | /* cfa_how deliberately not set. */ |
496 | break; | |
497 | ||
a8504492 MK |
498 | case DW_CFA_nop: |
499 | break; | |
500 | ||
cfc14b3a | 501 | case DW_CFA_def_cfa_expression: |
f664829e DE |
502 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
503 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
504 | fs->regs.cfa_exp = insn_ptr; |
505 | fs->regs.cfa_how = CFA_EXP; | |
506 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
507 | break; |
508 | ||
509 | case DW_CFA_expression: | |
f664829e | 510 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 511 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
1c90d9f0 | 512 | fs->regs.alloc_regs (reg + 1); |
f664829e | 513 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
514 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
515 | fs->regs.reg[reg].loc.exp.len = utmp; | |
05cbe71a | 516 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
517 | insn_ptr += utmp; |
518 | break; | |
519 | ||
a8504492 | 520 | case DW_CFA_offset_extended_sf: |
f664829e | 521 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 522 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 523 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 524 | offset *= fs->data_align; |
1c90d9f0 | 525 | fs->regs.alloc_regs (reg + 1); |
05cbe71a | 526 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
527 | fs->regs.reg[reg].loc.offset = offset; |
528 | break; | |
529 | ||
46ea248b | 530 | case DW_CFA_val_offset: |
f664829e | 531 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 532 | fs->regs.alloc_regs (reg + 1); |
f664829e | 533 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
534 | offset = utmp * fs->data_align; |
535 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
536 | fs->regs.reg[reg].loc.offset = offset; | |
537 | break; | |
538 | ||
539 | case DW_CFA_val_offset_sf: | |
f664829e | 540 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 541 | fs->regs.alloc_regs (reg + 1); |
f664829e | 542 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
543 | offset *= fs->data_align; |
544 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
545 | fs->regs.reg[reg].loc.offset = offset; | |
546 | break; | |
547 | ||
548 | case DW_CFA_val_expression: | |
f664829e | 549 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
1c90d9f0 | 550 | fs->regs.alloc_regs (reg + 1); |
f664829e | 551 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
b348037f YQ |
552 | fs->regs.reg[reg].loc.exp.start = insn_ptr; |
553 | fs->regs.reg[reg].loc.exp.len = utmp; | |
46ea248b AO |
554 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; |
555 | insn_ptr += utmp; | |
556 | break; | |
557 | ||
a8504492 | 558 | case DW_CFA_def_cfa_sf: |
f664829e DE |
559 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
560 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 | 561 | eh_frame_p); |
f664829e | 562 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
563 | fs->regs.cfa_offset = offset * fs->data_align; |
564 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
565 | break; |
566 | ||
567 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 568 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 569 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 570 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
571 | break; |
572 | ||
573 | case DW_CFA_GNU_args_size: | |
574 | /* Ignored. */ | |
f664829e | 575 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
576 | break; |
577 | ||
58894217 | 578 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 579 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 580 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
581 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
582 | offset = utmp * fs->data_align; | |
1c90d9f0 | 583 | fs->regs.alloc_regs (reg + 1); |
58894217 JK |
584 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
585 | fs->regs.reg[reg].loc.offset = -offset; | |
586 | break; | |
587 | ||
cfc14b3a | 588 | default: |
b41c5a85 JW |
589 | if (insn >= DW_CFA_lo_user && insn <= DW_CFA_hi_user) |
590 | { | |
591 | /* Handle vendor-specific CFI for different architectures. */ | |
592 | if (!gdbarch_execute_dwarf_cfa_vendor_op (gdbarch, insn, fs)) | |
593 | error (_("Call Frame Instruction op %d in vendor extension " | |
594 | "space is not handled on this architecture."), | |
595 | insn); | |
596 | } | |
597 | else | |
598 | internal_error (__FILE__, __LINE__, | |
599 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
600 | } |
601 | } | |
602 | } | |
603 | ||
780942fc | 604 | if (fs->initial.reg.empty ()) |
111c6489 JK |
605 | { |
606 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
1c90d9f0 | 607 | delete fs->regs.prev; |
111c6489 JK |
608 | fs->regs.prev = NULL; |
609 | } | |
610 | ||
611 | return insn_ptr; | |
cfc14b3a | 612 | } |
1c90d9f0 YQ |
613 | |
614 | #if GDB_SELF_TEST | |
615 | ||
616 | namespace selftests { | |
617 | ||
618 | /* Unit test to function execute_cfa_program. */ | |
619 | ||
620 | static void | |
621 | execute_cfa_program_test (struct gdbarch *gdbarch) | |
622 | { | |
623 | struct dwarf2_fde fde; | |
624 | struct dwarf2_cie cie; | |
625 | ||
626 | memset (&fde, 0, sizeof fde); | |
627 | memset (&cie, 0, sizeof cie); | |
628 | ||
629 | cie.data_alignment_factor = -4; | |
630 | cie.code_alignment_factor = 2; | |
631 | fde.cie = &cie; | |
632 | ||
633 | dwarf2_frame_state fs (0, fde.cie); | |
634 | ||
635 | gdb_byte insns[] = | |
636 | { | |
637 | DW_CFA_def_cfa, 1, 4, /* DW_CFA_def_cfa: r1 ofs 4 */ | |
638 | DW_CFA_offset | 0x2, 1, /* DW_CFA_offset: r2 at cfa-4 */ | |
639 | DW_CFA_remember_state, | |
640 | DW_CFA_restore_state, | |
641 | }; | |
642 | ||
643 | const gdb_byte *insn_end = insns + sizeof (insns); | |
644 | const gdb_byte *out = execute_cfa_program (&fde, insns, insn_end, gdbarch, | |
645 | 0, &fs); | |
646 | ||
647 | SELF_CHECK (out == insn_end); | |
648 | SELF_CHECK (fs.pc == 0); | |
649 | ||
650 | /* The instructions above only use r1 and r2, but the register numbers | |
651 | used are adjusted by dwarf2_frame_adjust_regnum. */ | |
652 | auto r1 = dwarf2_frame_adjust_regnum (gdbarch, 1, fde.eh_frame_p); | |
653 | auto r2 = dwarf2_frame_adjust_regnum (gdbarch, 2, fde.eh_frame_p); | |
654 | ||
780942fc | 655 | SELF_CHECK (fs.regs.reg.size () == (std::max (r1, r2) + 1)); |
1c90d9f0 YQ |
656 | |
657 | SELF_CHECK (fs.regs.reg[r2].how == DWARF2_FRAME_REG_SAVED_OFFSET); | |
658 | SELF_CHECK (fs.regs.reg[r2].loc.offset == -4); | |
659 | ||
780942fc | 660 | for (auto i = 0; i < fs.regs.reg.size (); i++) |
1c90d9f0 YQ |
661 | if (i != r2) |
662 | SELF_CHECK (fs.regs.reg[i].how == DWARF2_FRAME_REG_UNSPECIFIED); | |
663 | ||
664 | SELF_CHECK (fs.regs.cfa_reg == 1); | |
665 | SELF_CHECK (fs.regs.cfa_offset == 4); | |
666 | SELF_CHECK (fs.regs.cfa_how == CFA_REG_OFFSET); | |
667 | SELF_CHECK (fs.regs.cfa_exp == NULL); | |
668 | SELF_CHECK (fs.regs.prev == NULL); | |
669 | } | |
670 | ||
671 | } // namespace selftests | |
672 | #endif /* GDB_SELF_TEST */ | |
673 | ||
8f22cb90 | 674 | \f |
cfc14b3a | 675 | |
8f22cb90 | 676 | /* Architecture-specific operations. */ |
cfc14b3a | 677 | |
8f22cb90 MK |
678 | /* Per-architecture data key. */ |
679 | static struct gdbarch_data *dwarf2_frame_data; | |
680 | ||
681 | struct dwarf2_frame_ops | |
682 | { | |
683 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
684 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
685 | struct frame_info *); | |
3ed09a32 | 686 | |
4a4e5149 | 687 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 688 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 689 | |
4fc771b8 DJ |
690 | /* Convert .eh_frame register number to DWARF register number, or |
691 | adjust .debug_frame register number. */ | |
692 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
693 | }; |
694 | ||
8f22cb90 MK |
695 | /* Default architecture-specific register state initialization |
696 | function. */ | |
697 | ||
698 | static void | |
699 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 700 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 701 | struct frame_info *this_frame) |
8f22cb90 MK |
702 | { |
703 | /* If we have a register that acts as a program counter, mark it as | |
704 | a destination for the return address. If we have a register that | |
705 | serves as the stack pointer, arrange for it to be filled with the | |
706 | call frame address (CFA). The other registers are marked as | |
707 | unspecified. | |
708 | ||
709 | We copy the return address to the program counter, since many | |
710 | parts in GDB assume that it is possible to get the return address | |
711 | by unwinding the program counter register. However, on ISA's | |
712 | with a dedicated return address register, the CFI usually only | |
713 | contains information to unwind that return address register. | |
714 | ||
715 | The reason we're treating the stack pointer special here is | |
716 | because in many cases GCC doesn't emit CFI for the stack pointer | |
717 | and implicitly assumes that it is equal to the CFA. This makes | |
718 | some sense since the DWARF specification (version 3, draft 8, | |
719 | p. 102) says that: | |
720 | ||
721 | "Typically, the CFA is defined to be the value of the stack | |
722 | pointer at the call site in the previous frame (which may be | |
723 | different from its value on entry to the current frame)." | |
724 | ||
725 | However, this isn't true for all platforms supported by GCC | |
726 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
727 | their own architecture-specific initialization function. */ | |
05cbe71a | 728 | |
ad010def | 729 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 730 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 731 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
732 | reg->how = DWARF2_FRAME_REG_CFA; |
733 | } | |
05cbe71a | 734 | |
8f22cb90 | 735 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 736 | |
8f22cb90 | 737 | static void * |
030f20e1 | 738 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
739 | { |
740 | struct dwarf2_frame_ops *ops; | |
741 | ||
030f20e1 | 742 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
743 | ops->init_reg = dwarf2_frame_default_init_reg; |
744 | return ops; | |
745 | } | |
05cbe71a | 746 | |
8f22cb90 MK |
747 | /* Set the architecture-specific register state initialization |
748 | function for GDBARCH to INIT_REG. */ | |
749 | ||
750 | void | |
751 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
752 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
753 | struct dwarf2_frame_state_reg *, |
754 | struct frame_info *)) | |
8f22cb90 | 755 | { |
9a3c8263 SM |
756 | struct dwarf2_frame_ops *ops |
757 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 758 | |
8f22cb90 MK |
759 | ops->init_reg = init_reg; |
760 | } | |
761 | ||
762 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
763 | |
764 | static void | |
765 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 766 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 767 | struct frame_info *this_frame) |
05cbe71a | 768 | { |
9a3c8263 SM |
769 | struct dwarf2_frame_ops *ops |
770 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
8f22cb90 | 771 | |
4a4e5149 | 772 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 773 | } |
3ed09a32 DJ |
774 | |
775 | /* Set the architecture-specific signal trampoline recognition | |
776 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
777 | ||
778 | void | |
779 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
780 | int (*signal_frame_p) (struct gdbarch *, | |
781 | struct frame_info *)) | |
782 | { | |
9a3c8263 SM |
783 | struct dwarf2_frame_ops *ops |
784 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
785 | |
786 | ops->signal_frame_p = signal_frame_p; | |
787 | } | |
788 | ||
789 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 790 | THIS_FRAME. */ |
3ed09a32 DJ |
791 | |
792 | static int | |
793 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 794 | struct frame_info *this_frame) |
3ed09a32 | 795 | { |
9a3c8263 SM |
796 | struct dwarf2_frame_ops *ops |
797 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
3ed09a32 DJ |
798 | |
799 | if (ops->signal_frame_p == NULL) | |
800 | return 0; | |
4a4e5149 | 801 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 802 | } |
4bf8967c | 803 | |
4fc771b8 DJ |
804 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
805 | register numbers. */ | |
4bf8967c AS |
806 | |
807 | void | |
4fc771b8 DJ |
808 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
809 | int (*adjust_regnum) (struct gdbarch *, | |
810 | int, int)) | |
4bf8967c | 811 | { |
9a3c8263 SM |
812 | struct dwarf2_frame_ops *ops |
813 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 814 | |
4fc771b8 | 815 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
816 | } |
817 | ||
4fc771b8 DJ |
818 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
819 | register. */ | |
4bf8967c | 820 | |
4fc771b8 | 821 | static int |
3e43a32a MS |
822 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
823 | int regnum, int eh_frame_p) | |
4bf8967c | 824 | { |
9a3c8263 SM |
825 | struct dwarf2_frame_ops *ops |
826 | = (struct dwarf2_frame_ops *) gdbarch_data (gdbarch, dwarf2_frame_data); | |
4bf8967c | 827 | |
4fc771b8 | 828 | if (ops->adjust_regnum == NULL) |
4bf8967c | 829 | return regnum; |
4fc771b8 | 830 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 831 | } |
303b6f5d DJ |
832 | |
833 | static void | |
834 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
835 | struct dwarf2_fde *fde) | |
836 | { | |
43f3e411 | 837 | struct compunit_symtab *cust; |
303b6f5d | 838 | |
43f3e411 DE |
839 | cust = find_pc_compunit_symtab (fs->pc); |
840 | if (cust == NULL) | |
303b6f5d DJ |
841 | return; |
842 | ||
43f3e411 | 843 | if (producer_is_realview (COMPUNIT_PRODUCER (cust))) |
a6c727b2 DJ |
844 | { |
845 | if (fde->cie->version == 1) | |
846 | fs->armcc_cfa_offsets_sf = 1; | |
847 | ||
848 | if (fde->cie->version == 1) | |
849 | fs->armcc_cfa_offsets_reversed = 1; | |
850 | ||
851 | /* The reversed offset problem is present in some compilers | |
852 | using DWARF3, but it was eventually fixed. Check the ARM | |
853 | defined augmentations, which are in the format "armcc" followed | |
854 | by a list of one-character options. The "+" option means | |
855 | this problem is fixed (no quirk needed). If the armcc | |
856 | augmentation is missing, the quirk is needed. */ | |
857 | if (fde->cie->version == 3 | |
61012eef | 858 | && (!startswith (fde->cie->augmentation, "armcc") |
a6c727b2 DJ |
859 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) |
860 | fs->armcc_cfa_offsets_reversed = 1; | |
861 | ||
862 | return; | |
863 | } | |
303b6f5d | 864 | } |
8f22cb90 MK |
865 | \f |
866 | ||
a8fd5589 TT |
867 | /* See dwarf2-frame.h. */ |
868 | ||
869 | int | |
870 | dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc, | |
871 | struct dwarf2_per_cu_data *data, | |
872 | int *regnum_out, LONGEST *offset_out, | |
873 | CORE_ADDR *text_offset_out, | |
874 | const gdb_byte **cfa_start_out, | |
875 | const gdb_byte **cfa_end_out) | |
9f6f94ff | 876 | { |
9f6f94ff | 877 | struct dwarf2_fde *fde; |
22e048c9 | 878 | CORE_ADDR text_offset; |
afe37d6b | 879 | CORE_ADDR pc1 = pc; |
9f6f94ff TT |
880 | |
881 | /* Find the correct FDE. */ | |
afe37d6b | 882 | fde = dwarf2_frame_find_fde (&pc1, &text_offset); |
9f6f94ff TT |
883 | if (fde == NULL) |
884 | error (_("Could not compute CFA; needed to translate this expression")); | |
885 | ||
afe37d6b | 886 | dwarf2_frame_state fs (pc1, fde->cie); |
9f6f94ff TT |
887 | |
888 | /* Check for "quirks" - known bugs in producers. */ | |
889 | dwarf2_frame_find_quirks (&fs, fde); | |
890 | ||
891 | /* First decode all the insns in the CIE. */ | |
892 | execute_cfa_program (fde, fde->cie->initial_instructions, | |
893 | fde->cie->end, gdbarch, pc, &fs); | |
894 | ||
895 | /* Save the initialized register set. */ | |
896 | fs.initial = fs.regs; | |
9f6f94ff TT |
897 | |
898 | /* Then decode the insns in the FDE up to our target PC. */ | |
899 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs); | |
900 | ||
901 | /* Calculate the CFA. */ | |
902 | switch (fs.regs.cfa_how) | |
903 | { | |
904 | case CFA_REG_OFFSET: | |
905 | { | |
0fde2c53 | 906 | int regnum = dwarf_reg_to_regnum_or_error (gdbarch, fs.regs.cfa_reg); |
a8fd5589 TT |
907 | |
908 | *regnum_out = regnum; | |
909 | if (fs.armcc_cfa_offsets_reversed) | |
910 | *offset_out = -fs.regs.cfa_offset; | |
911 | else | |
912 | *offset_out = fs.regs.cfa_offset; | |
913 | return 1; | |
9f6f94ff | 914 | } |
9f6f94ff TT |
915 | |
916 | case CFA_EXP: | |
a8fd5589 TT |
917 | *text_offset_out = text_offset; |
918 | *cfa_start_out = fs.regs.cfa_exp; | |
919 | *cfa_end_out = fs.regs.cfa_exp + fs.regs.cfa_exp_len; | |
920 | return 0; | |
9f6f94ff TT |
921 | |
922 | default: | |
923 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
924 | } | |
925 | } | |
926 | ||
927 | \f | |
8f22cb90 MK |
928 | struct dwarf2_frame_cache |
929 | { | |
930 | /* DWARF Call Frame Address. */ | |
931 | CORE_ADDR cfa; | |
932 | ||
8fbca658 PA |
933 | /* Set if the return address column was marked as unavailable |
934 | (required non-collected memory or registers to compute). */ | |
935 | int unavailable_retaddr; | |
936 | ||
0228dfb9 DJ |
937 | /* Set if the return address column was marked as undefined. */ |
938 | int undefined_retaddr; | |
939 | ||
8f22cb90 MK |
940 | /* Saved registers, indexed by GDB register number, not by DWARF |
941 | register number. */ | |
942 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
943 | |
944 | /* Return address register. */ | |
945 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
946 | |
947 | /* Target address size in bytes. */ | |
948 | int addr_size; | |
ac56253d TT |
949 | |
950 | /* The .text offset. */ | |
951 | CORE_ADDR text_offset; | |
111c6489 | 952 | |
1ec56e88 PA |
953 | /* True if we already checked whether this frame is the bottom frame |
954 | of a virtual tail call frame chain. */ | |
955 | int checked_tailcall_bottom; | |
956 | ||
111c6489 JK |
957 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME |
958 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
959 | involved. Non-bottom frames of a virtual tail call frames chain use | |
960 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
961 | them. */ | |
962 | void *tailcall_cache; | |
1ec56e88 PA |
963 | |
964 | /* The number of bytes to subtract from TAILCALL_FRAME frames frame | |
965 | base to get the SP, to simulate the return address pushed on the | |
966 | stack. */ | |
967 | LONGEST entry_cfa_sp_offset; | |
968 | int entry_cfa_sp_offset_p; | |
8f22cb90 | 969 | }; |
05cbe71a | 970 | |
b9362cc7 | 971 | static struct dwarf2_frame_cache * |
4a4e5149 | 972 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 973 | { |
4a4e5149 | 974 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
f6efe3f8 | 975 | const int num_regs = gdbarch_num_cooked_regs (gdbarch); |
cfc14b3a | 976 | struct dwarf2_frame_cache *cache; |
cfc14b3a | 977 | struct dwarf2_fde *fde; |
111c6489 | 978 | CORE_ADDR entry_pc; |
111c6489 | 979 | const gdb_byte *instr; |
cfc14b3a MK |
980 | |
981 | if (*this_cache) | |
9a3c8263 | 982 | return (struct dwarf2_frame_cache *) *this_cache; |
cfc14b3a MK |
983 | |
984 | /* Allocate a new cache. */ | |
985 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
986 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 987 | *this_cache = cache; |
cfc14b3a | 988 | |
cfc14b3a MK |
989 | /* Unwind the PC. |
990 | ||
4a4e5149 | 991 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 992 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 993 | its return address. As a result the return address will |
cfc14b3a | 994 | point at some random instruction, and the CFI for that |
e4e9607c | 995 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
996 | this problem by substracting 1 from the return address to get an |
997 | address in the middle of a presumed call instruction (or the | |
998 | instruction in the associated delay slot). This should only be | |
999 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 1000 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 1001 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
1002 | reliable the method is though; there is the potential for the |
1003 | register state pre-call being different to that on return. */ | |
afe37d6b | 1004 | CORE_ADDR pc1 = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1005 | |
1006 | /* Find the correct FDE. */ | |
afe37d6b | 1007 | fde = dwarf2_frame_find_fde (&pc1, &cache->text_offset); |
cfc14b3a MK |
1008 | gdb_assert (fde != NULL); |
1009 | ||
afe37d6b YQ |
1010 | /* Allocate and initialize the frame state. */ |
1011 | struct dwarf2_frame_state fs (pc1, fde->cie); | |
1012 | ||
ae0d2f24 | 1013 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1014 | |
303b6f5d | 1015 | /* Check for "quirks" - known bugs in producers. */ |
afe37d6b | 1016 | dwarf2_frame_find_quirks (&fs, fde); |
303b6f5d | 1017 | |
cfc14b3a | 1018 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1019 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 | 1020 | fde->cie->end, gdbarch, |
afe37d6b | 1021 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a MK |
1022 | |
1023 | /* Save the initialized register set. */ | |
afe37d6b | 1024 | fs.initial = fs.regs; |
cfc14b3a | 1025 | |
1aff7173 KB |
1026 | /* Fetching the entry pc for THIS_FRAME won't necessarily result |
1027 | in an address that's within the range of FDE locations. This | |
1028 | is due to the possibility of the function occupying non-contiguous | |
1029 | ranges. */ | |
1030 | if (get_frame_func_if_available (this_frame, &entry_pc) | |
1031 | && fde->initial_location <= entry_pc | |
1032 | && entry_pc < fde->initial_location + fde->address_range) | |
111c6489 JK |
1033 | { |
1034 | /* Decode the insns in the FDE up to the entry PC. */ | |
1035 | instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, | |
afe37d6b | 1036 | entry_pc, &fs); |
111c6489 | 1037 | |
afe37d6b YQ |
1038 | if (fs.regs.cfa_how == CFA_REG_OFFSET |
1039 | && (dwarf_reg_to_regnum (gdbarch, fs.regs.cfa_reg) | |
111c6489 JK |
1040 | == gdbarch_sp_regnum (gdbarch))) |
1041 | { | |
afe37d6b | 1042 | cache->entry_cfa_sp_offset = fs.regs.cfa_offset; |
1ec56e88 | 1043 | cache->entry_cfa_sp_offset_p = 1; |
111c6489 JK |
1044 | } |
1045 | } | |
1046 | else | |
1047 | instr = fde->instructions; | |
1048 | ||
cfc14b3a | 1049 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1050 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
afe37d6b | 1051 | get_frame_address_in_block (this_frame), &fs); |
cfc14b3a | 1052 | |
a70b8144 | 1053 | try |
cfc14b3a | 1054 | { |
8fbca658 | 1055 | /* Calculate the CFA. */ |
afe37d6b | 1056 | switch (fs.regs.cfa_how) |
8fbca658 PA |
1057 | { |
1058 | case CFA_REG_OFFSET: | |
afe37d6b YQ |
1059 | cache->cfa = read_addr_from_reg (this_frame, fs.regs.cfa_reg); |
1060 | if (fs.armcc_cfa_offsets_reversed) | |
1061 | cache->cfa -= fs.regs.cfa_offset; | |
8fbca658 | 1062 | else |
afe37d6b | 1063 | cache->cfa += fs.regs.cfa_offset; |
8fbca658 PA |
1064 | break; |
1065 | ||
1066 | case CFA_EXP: | |
1067 | cache->cfa = | |
afe37d6b | 1068 | execute_stack_op (fs.regs.cfa_exp, fs.regs.cfa_exp_len, |
8fbca658 PA |
1069 | cache->addr_size, cache->text_offset, |
1070 | this_frame, 0, 0); | |
1071 | break; | |
1072 | ||
1073 | default: | |
1074 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1075 | } | |
1076 | } | |
230d2906 | 1077 | catch (const gdb_exception_error &ex) |
8fbca658 PA |
1078 | { |
1079 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1080 | { | |
1081 | cache->unavailable_retaddr = 1; | |
1082 | return cache; | |
1083 | } | |
cfc14b3a | 1084 | |
eedc3f4f | 1085 | throw; |
cfc14b3a MK |
1086 | } |
1087 | ||
05cbe71a | 1088 | /* Initialize the register state. */ |
3e2c4033 AC |
1089 | { |
1090 | int regnum; | |
e4e9607c | 1091 | |
3e2c4033 | 1092 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1093 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1094 | } |
1095 | ||
1096 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1097 | location information in the cache. Note that we don't skip the |
1098 | return address column; it's perfectly all right for it to | |
0fde2c53 | 1099 | correspond to a real register. */ |
3e2c4033 AC |
1100 | { |
1101 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1102 | |
780942fc | 1103 | for (column = 0; column < fs.regs.reg.size (); column++) |
3e2c4033 | 1104 | { |
3e2c4033 | 1105 | /* Use the GDB register number as the destination index. */ |
0fde2c53 | 1106 | int regnum = dwarf_reg_to_regnum (gdbarch, column); |
3e2c4033 | 1107 | |
0fde2c53 | 1108 | /* Protect against a target returning a bad register. */ |
3e2c4033 AC |
1109 | if (regnum < 0 || regnum >= num_regs) |
1110 | continue; | |
1111 | ||
1112 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1113 | of all debug info registers. If it doesn't, complain (but |
1114 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1115 | unspecified register implies "same value" when CFI (draft |
1116 | 7) specifies nothing at all. Such a register could equally | |
1117 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1118 | isn't sufficient; it only checks that all registers in the |
1119 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1120 | problems when a debug info register falls outside of the |
e4e9607c | 1121 | table. We need a way of iterating through all the valid |
3e2c4033 | 1122 | DWARF2 register numbers. */ |
afe37d6b | 1123 | if (fs.regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1124 | { |
1125 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
b98664d3 | 1126 | complaint (_("\ |
5af949e3 | 1127 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1128 | gdbarch_register_name (gdbarch, regnum), |
afe37d6b | 1129 | paddress (gdbarch, fs.pc)); |
f059bf6f | 1130 | } |
35889917 | 1131 | else |
afe37d6b | 1132 | cache->reg[regnum] = fs.regs.reg[column]; |
3e2c4033 AC |
1133 | } |
1134 | } | |
cfc14b3a | 1135 | |
8d5a9abc MK |
1136 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1137 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1138 | { |
1139 | int regnum; | |
1140 | ||
1141 | for (regnum = 0; regnum < num_regs; regnum++) | |
1142 | { | |
8d5a9abc MK |
1143 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1144 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1145 | { |
780942fc TT |
1146 | const std::vector<struct dwarf2_frame_state_reg> ®s |
1147 | = fs.regs.reg; | |
1148 | ULONGEST retaddr_column = fs.retaddr_column; | |
05cbe71a | 1149 | |
d4f10bf2 MK |
1150 | /* It seems rather bizarre to specify an "empty" column as |
1151 | the return adress column. However, this is exactly | |
1152 | what GCC does on some targets. It turns out that GCC | |
1153 | assumes that the return address can be found in the | |
1154 | register corresponding to the return address column. | |
8d5a9abc MK |
1155 | Incidentally, that's how we should treat a return |
1156 | address column specifying "same value" too. */ | |
780942fc TT |
1157 | if (fs.retaddr_column < fs.regs.reg.size () |
1158 | && regs[retaddr_column].how != DWARF2_FRAME_REG_UNSPECIFIED | |
1159 | && regs[retaddr_column].how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1160 | { |
1161 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
780942fc | 1162 | cache->reg[regnum] = regs[retaddr_column]; |
8d5a9abc | 1163 | else |
780942fc | 1164 | cache->retaddr_reg = regs[retaddr_column]; |
8d5a9abc | 1165 | } |
35889917 MK |
1166 | else |
1167 | { | |
8d5a9abc MK |
1168 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1169 | { | |
afe37d6b | 1170 | cache->reg[regnum].loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1171 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; |
1172 | } | |
1173 | else | |
1174 | { | |
afe37d6b | 1175 | cache->retaddr_reg.loc.reg = fs.retaddr_column; |
8d5a9abc MK |
1176 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; |
1177 | } | |
35889917 MK |
1178 | } |
1179 | } | |
1180 | } | |
1181 | } | |
cfc14b3a | 1182 | |
780942fc | 1183 | if (fs.retaddr_column < fs.regs.reg.size () |
afe37d6b | 1184 | && fs.regs.reg[fs.retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) |
0228dfb9 DJ |
1185 | cache->undefined_retaddr = 1; |
1186 | ||
cfc14b3a MK |
1187 | return cache; |
1188 | } | |
1189 | ||
8fbca658 PA |
1190 | static enum unwind_stop_reason |
1191 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1192 | void **this_cache) | |
1193 | { | |
1194 | struct dwarf2_frame_cache *cache | |
1195 | = dwarf2_frame_cache (this_frame, this_cache); | |
1196 | ||
1197 | if (cache->unavailable_retaddr) | |
1198 | return UNWIND_UNAVAILABLE; | |
1199 | ||
1200 | if (cache->undefined_retaddr) | |
1201 | return UNWIND_OUTERMOST; | |
1202 | ||
1203 | return UNWIND_NO_REASON; | |
1204 | } | |
1205 | ||
cfc14b3a | 1206 | static void |
4a4e5149 | 1207 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1208 | struct frame_id *this_id) |
1209 | { | |
1210 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1211 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1212 | |
8fbca658 | 1213 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1214 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1215 | else if (cache->undefined_retaddr) | |
8fbca658 | 1216 | return; |
5ce0145d PA |
1217 | else |
1218 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1219 | } |
1220 | ||
4a4e5149 DJ |
1221 | static struct value * |
1222 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1223 | int regnum) | |
93d42b30 | 1224 | { |
4a4e5149 | 1225 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1226 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1227 | dwarf2_frame_cache (this_frame, this_cache); |
1228 | CORE_ADDR addr; | |
1229 | int realnum; | |
cfc14b3a | 1230 | |
1ec56e88 PA |
1231 | /* Check whether THIS_FRAME is the bottom frame of a virtual tail |
1232 | call frame chain. */ | |
1233 | if (!cache->checked_tailcall_bottom) | |
1234 | { | |
1235 | cache->checked_tailcall_bottom = 1; | |
1236 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, | |
1237 | (cache->entry_cfa_sp_offset_p | |
1238 | ? &cache->entry_cfa_sp_offset : NULL)); | |
1239 | } | |
1240 | ||
111c6489 JK |
1241 | /* Non-bottom frames of a virtual tail call frames chain use |
1242 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1243 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1244 | unwind the register, tail call frames are assumed to have the register set | |
1245 | of the top caller. */ | |
1246 | if (cache->tailcall_cache) | |
1247 | { | |
1248 | struct value *val; | |
1249 | ||
1250 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1251 | &cache->tailcall_cache, | |
1252 | regnum); | |
1253 | if (val) | |
1254 | return val; | |
1255 | } | |
1256 | ||
cfc14b3a MK |
1257 | switch (cache->reg[regnum].how) |
1258 | { | |
05cbe71a | 1259 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1260 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1261 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1262 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1263 | |
05cbe71a | 1264 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1265 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1266 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1267 | |
05cbe71a | 1268 | case DWARF2_FRAME_REG_SAVED_REG: |
0fde2c53 DE |
1269 | realnum = dwarf_reg_to_regnum_or_error |
1270 | (gdbarch, cache->reg[regnum].loc.reg); | |
4a4e5149 | 1271 | return frame_unwind_got_register (this_frame, regnum, realnum); |
cfc14b3a | 1272 | |
05cbe71a | 1273 | case DWARF2_FRAME_REG_SAVED_EXP: |
b348037f YQ |
1274 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1275 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1276 | cache->addr_size, cache->text_offset, |
1277 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1278 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1279 | |
46ea248b | 1280 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1281 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1282 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1283 | |
1284 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
b348037f YQ |
1285 | addr = execute_stack_op (cache->reg[regnum].loc.exp.start, |
1286 | cache->reg[regnum].loc.exp.len, | |
ac56253d TT |
1287 | cache->addr_size, cache->text_offset, |
1288 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1289 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1290 | |
05cbe71a | 1291 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1292 | /* GCC, in its infinite wisdom decided to not provide unwind |
1293 | information for registers that are "same value". Since | |
1294 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1295 | registers are actually undefined (which is different to CFI | |
1296 | "undefined"). Code above issues a complaint about this. | |
1297 | Here just fudge the books, assume GCC, and that the value is | |
1298 | more inner on the stack. */ | |
4a4e5149 | 1299 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1300 | |
05cbe71a | 1301 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1302 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1303 | |
05cbe71a | 1304 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1305 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1306 | |
ea7963f0 | 1307 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1308 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1309 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1310 | |
8d5a9abc | 1311 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 | 1312 | addr = cache->reg[regnum].loc.offset; |
0fde2c53 | 1313 | regnum = dwarf_reg_to_regnum_or_error |
4a4e5149 DJ |
1314 | (gdbarch, cache->retaddr_reg.loc.reg); |
1315 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1316 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1317 | |
b39cc962 DJ |
1318 | case DWARF2_FRAME_REG_FN: |
1319 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1320 | ||
cfc14b3a | 1321 | default: |
e2e0b3e5 | 1322 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1323 | } |
1324 | } | |
1325 | ||
111c6489 JK |
1326 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1327 | call frames chain. */ | |
1328 | ||
1329 | static void | |
1330 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1331 | { | |
1332 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1333 | ||
1334 | if (cache->tailcall_cache) | |
1335 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1336 | } | |
1337 | ||
4a4e5149 DJ |
1338 | static int |
1339 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1340 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1341 | { |
3c3bb058 AB |
1342 | if (!dwarf2_frame_unwinders_enabled_p) |
1343 | return 0; | |
1344 | ||
1ce5d6dd | 1345 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1346 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1347 | end up returning something past the end of this function's body. |
1348 | If the frame we're sniffing for is a signal frame whose start | |
1349 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1350 | extend one byte before its start address or we could potentially |
1351 | select the FDE of the previous function. */ | |
1352 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1353 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1354 | |
56c987f6 | 1355 | if (!fde) |
4a4e5149 | 1356 | return 0; |
3ed09a32 DJ |
1357 | |
1358 | /* On some targets, signal trampolines may have unwind information. | |
1359 | We need to recognize them so that we set the frame type | |
1360 | correctly. */ | |
1361 | ||
56c987f6 | 1362 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1363 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1364 | this_frame)) | |
1365 | return self->type == SIGTRAMP_FRAME; | |
1366 | ||
111c6489 JK |
1367 | if (self->type != NORMAL_FRAME) |
1368 | return 0; | |
1369 | ||
111c6489 | 1370 | return 1; |
4a4e5149 DJ |
1371 | } |
1372 | ||
1373 | static const struct frame_unwind dwarf2_frame_unwind = | |
1374 | { | |
1375 | NORMAL_FRAME, | |
8fbca658 | 1376 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1377 | dwarf2_frame_this_id, |
1378 | dwarf2_frame_prev_register, | |
1379 | NULL, | |
111c6489 JK |
1380 | dwarf2_frame_sniffer, |
1381 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1382 | }; |
1383 | ||
1384 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1385 | { | |
1386 | SIGTRAMP_FRAME, | |
8fbca658 | 1387 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1388 | dwarf2_frame_this_id, |
1389 | dwarf2_frame_prev_register, | |
1390 | NULL, | |
111c6489 JK |
1391 | dwarf2_frame_sniffer, |
1392 | ||
1393 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1394 | NULL | |
4a4e5149 | 1395 | }; |
cfc14b3a | 1396 | |
4a4e5149 DJ |
1397 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1398 | ||
1399 | void | |
1400 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1401 | { | |
111c6489 JK |
1402 | /* TAILCALL_FRAME must be first to find the record by |
1403 | dwarf2_tailcall_sniffer_first. */ | |
1404 | frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind); | |
1405 | ||
4a4e5149 DJ |
1406 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); |
1407 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1408 | } |
1409 | \f | |
1410 | ||
1411 | /* There is no explicitly defined relationship between the CFA and the | |
1412 | location of frame's local variables and arguments/parameters. | |
1413 | Therefore, frame base methods on this page should probably only be | |
1414 | used as a last resort, just to avoid printing total garbage as a | |
1415 | response to the "info frame" command. */ | |
1416 | ||
1417 | static CORE_ADDR | |
4a4e5149 | 1418 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1419 | { |
1420 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1421 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1422 | |
1423 | return cache->cfa; | |
1424 | } | |
1425 | ||
1426 | static const struct frame_base dwarf2_frame_base = | |
1427 | { | |
1428 | &dwarf2_frame_unwind, | |
1429 | dwarf2_frame_base_address, | |
1430 | dwarf2_frame_base_address, | |
1431 | dwarf2_frame_base_address | |
1432 | }; | |
1433 | ||
1434 | const struct frame_base * | |
4a4e5149 | 1435 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1436 | { |
4a4e5149 | 1437 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1438 | |
ac56253d | 1439 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1440 | return &dwarf2_frame_base; |
1441 | ||
1442 | return NULL; | |
1443 | } | |
e7802207 TT |
1444 | |
1445 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1446 | the DWARF unwinder. This is used to implement | |
1447 | DW_OP_call_frame_cfa. */ | |
1448 | ||
1449 | CORE_ADDR | |
1450 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1451 | { | |
0b722aec MM |
1452 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1453 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1454 | throw_error (NOT_AVAILABLE_ERROR, | |
1455 | _("cfa not available for record btrace target")); | |
1456 | ||
e7802207 TT |
1457 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1458 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1459 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1460 | throw_error (NOT_AVAILABLE_ERROR, | |
1461 | _("can't compute CFA for this frame: " | |
1462 | "required registers or memory are unavailable")); | |
14aba1ac JB |
1463 | |
1464 | if (get_frame_id (this_frame).stack_status != FID_STACK_VALID) | |
1465 | throw_error (NOT_AVAILABLE_ERROR, | |
1466 | _("can't compute CFA for this frame: " | |
1467 | "frame base not available")); | |
1468 | ||
e7802207 TT |
1469 | return get_frame_base (this_frame); |
1470 | } | |
cfc14b3a | 1471 | \f |
924d79e2 TT |
1472 | const struct objfile_key<dwarf2_fde_table, |
1473 | gdb::noop_deleter<dwarf2_fde_table>> | |
1474 | dwarf2_frame_objfile_data; | |
0d0e1a63 | 1475 | |
cfc14b3a | 1476 | static unsigned int |
f664829e | 1477 | read_1_byte (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1478 | { |
852483bc | 1479 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1480 | } |
1481 | ||
1482 | static unsigned int | |
f664829e | 1483 | read_4_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1484 | { |
852483bc | 1485 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1486 | } |
1487 | ||
1488 | static ULONGEST | |
f664829e | 1489 | read_8_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1490 | { |
852483bc | 1491 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1492 | } |
1493 | ||
1494 | static ULONGEST | |
f664829e DE |
1495 | read_initial_length (bfd *abfd, const gdb_byte *buf, |
1496 | unsigned int *bytes_read_ptr) | |
cfc14b3a | 1497 | { |
723adb65 | 1498 | ULONGEST result; |
cfc14b3a | 1499 | |
852483bc | 1500 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1501 | if (result == 0xffffffff) |
1502 | { | |
852483bc | 1503 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1504 | *bytes_read_ptr = 12; |
1505 | } | |
1506 | else | |
1507 | *bytes_read_ptr = 4; | |
1508 | ||
1509 | return result; | |
1510 | } | |
1511 | \f | |
1512 | ||
1513 | /* Pointer encoding helper functions. */ | |
1514 | ||
1515 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1516 | technical reasons, it encodes addresses in its FDE's in a different | |
1517 | way. Several "pointer encodings" are supported. The encoding | |
1518 | that's used for a particular FDE is determined by the 'R' | |
1519 | augmentation in the associated CIE. The argument of this | |
1520 | augmentation is a single byte. | |
1521 | ||
1522 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1523 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1524 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1525 | address should be interpreted (absolute, relative to the current | |
1526 | position in the FDE, ...). Bit 7, indicates that the address | |
1527 | should be dereferenced. */ | |
1528 | ||
852483bc | 1529 | static gdb_byte |
cfc14b3a MK |
1530 | encoding_for_size (unsigned int size) |
1531 | { | |
1532 | switch (size) | |
1533 | { | |
1534 | case 2: | |
1535 | return DW_EH_PE_udata2; | |
1536 | case 4: | |
1537 | return DW_EH_PE_udata4; | |
1538 | case 8: | |
1539 | return DW_EH_PE_udata8; | |
1540 | default: | |
e2e0b3e5 | 1541 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1542 | } |
1543 | } | |
1544 | ||
cfc14b3a | 1545 | static CORE_ADDR |
852483bc | 1546 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1547 | int ptr_len, const gdb_byte *buf, |
1548 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1549 | CORE_ADDR func_base) |
cfc14b3a | 1550 | { |
68f6cf99 | 1551 | ptrdiff_t offset; |
cfc14b3a MK |
1552 | CORE_ADDR base; |
1553 | ||
1554 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1555 | FDE's. */ | |
1556 | if (encoding & DW_EH_PE_indirect) | |
1557 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1558 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1559 | |
68f6cf99 MK |
1560 | *bytes_read_ptr = 0; |
1561 | ||
cfc14b3a MK |
1562 | switch (encoding & 0x70) |
1563 | { | |
1564 | case DW_EH_PE_absptr: | |
1565 | base = 0; | |
1566 | break; | |
1567 | case DW_EH_PE_pcrel: | |
fd361982 | 1568 | base = bfd_section_vma (unit->dwarf_frame_section); |
852483bc | 1569 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1570 | break; |
0912c7f2 MK |
1571 | case DW_EH_PE_datarel: |
1572 | base = unit->dbase; | |
1573 | break; | |
0fd85043 CV |
1574 | case DW_EH_PE_textrel: |
1575 | base = unit->tbase; | |
1576 | break; | |
03ac2a74 | 1577 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1578 | base = func_base; |
03ac2a74 | 1579 | break; |
68f6cf99 MK |
1580 | case DW_EH_PE_aligned: |
1581 | base = 0; | |
852483bc | 1582 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1583 | if ((offset % ptr_len) != 0) |
1584 | { | |
1585 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1586 | buf += *bytes_read_ptr; | |
1587 | } | |
1588 | break; | |
cfc14b3a | 1589 | default: |
3e43a32a MS |
1590 | internal_error (__FILE__, __LINE__, |
1591 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1592 | } |
1593 | ||
b04de778 | 1594 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1595 | { |
1596 | encoding |= encoding_for_size (ptr_len); | |
1597 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1598 | encoding |= DW_EH_PE_signed; | |
1599 | } | |
cfc14b3a MK |
1600 | |
1601 | switch (encoding & 0x0f) | |
1602 | { | |
a81b10ae MK |
1603 | case DW_EH_PE_uleb128: |
1604 | { | |
9fccedf7 | 1605 | uint64_t value; |
0d45f56e | 1606 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1607 | |
f664829e | 1608 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1609 | return base + value; |
1610 | } | |
cfc14b3a | 1611 | case DW_EH_PE_udata2: |
68f6cf99 | 1612 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1613 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1614 | case DW_EH_PE_udata4: | |
68f6cf99 | 1615 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1616 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1617 | case DW_EH_PE_udata8: | |
68f6cf99 | 1618 | *bytes_read_ptr += 8; |
cfc14b3a | 1619 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1620 | case DW_EH_PE_sleb128: |
1621 | { | |
9fccedf7 | 1622 | int64_t value; |
0d45f56e | 1623 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1624 | |
f664829e | 1625 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1626 | return base + value; |
1627 | } | |
cfc14b3a | 1628 | case DW_EH_PE_sdata2: |
68f6cf99 | 1629 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1630 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1631 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1632 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1633 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1634 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1635 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1636 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1637 | default: | |
3e43a32a MS |
1638 | internal_error (__FILE__, __LINE__, |
1639 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1640 | } |
1641 | } | |
1642 | \f | |
1643 | ||
b01c8410 PP |
1644 | static int |
1645 | bsearch_cie_cmp (const void *key, const void *element) | |
cfc14b3a | 1646 | { |
b01c8410 PP |
1647 | ULONGEST cie_pointer = *(ULONGEST *) key; |
1648 | struct dwarf2_cie *cie = *(struct dwarf2_cie **) element; | |
cfc14b3a | 1649 | |
b01c8410 PP |
1650 | if (cie_pointer == cie->cie_pointer) |
1651 | return 0; | |
cfc14b3a | 1652 | |
b01c8410 PP |
1653 | return (cie_pointer < cie->cie_pointer) ? -1 : 1; |
1654 | } | |
1655 | ||
1656 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ | |
1657 | static struct dwarf2_cie * | |
1658 | find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer) | |
1659 | { | |
1660 | struct dwarf2_cie **p_cie; | |
cfc14b3a | 1661 | |
65a97ab3 PP |
1662 | /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to |
1663 | bsearch be non-NULL. */ | |
1664 | if (cie_table->entries == NULL) | |
1665 | { | |
1666 | gdb_assert (cie_table->num_entries == 0); | |
1667 | return NULL; | |
1668 | } | |
1669 | ||
9a3c8263 SM |
1670 | p_cie = ((struct dwarf2_cie **) |
1671 | bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries, | |
1672 | sizeof (cie_table->entries[0]), bsearch_cie_cmp)); | |
b01c8410 PP |
1673 | if (p_cie != NULL) |
1674 | return *p_cie; | |
cfc14b3a MK |
1675 | return NULL; |
1676 | } | |
1677 | ||
b01c8410 | 1678 | /* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */ |
cfc14b3a | 1679 | static void |
b01c8410 | 1680 | add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie) |
cfc14b3a | 1681 | { |
b01c8410 PP |
1682 | const int n = cie_table->num_entries; |
1683 | ||
1684 | gdb_assert (n < 1 | |
1685 | || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer); | |
1686 | ||
224c3ddb SM |
1687 | cie_table->entries |
1688 | = XRESIZEVEC (struct dwarf2_cie *, cie_table->entries, n + 1); | |
b01c8410 PP |
1689 | cie_table->entries[n] = cie; |
1690 | cie_table->num_entries = n + 1; | |
1691 | } | |
1692 | ||
1693 | static int | |
1694 | bsearch_fde_cmp (const void *key, const void *element) | |
1695 | { | |
1696 | CORE_ADDR seek_pc = *(CORE_ADDR *) key; | |
1697 | struct dwarf2_fde *fde = *(struct dwarf2_fde **) element; | |
9a619af0 | 1698 | |
b01c8410 PP |
1699 | if (seek_pc < fde->initial_location) |
1700 | return -1; | |
1701 | if (seek_pc < fde->initial_location + fde->address_range) | |
1702 | return 0; | |
1703 | return 1; | |
cfc14b3a MK |
1704 | } |
1705 | ||
1706 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1707 | inital location associated with it into *PC. */ | |
1708 | ||
1709 | static struct dwarf2_fde * | |
ac56253d | 1710 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a | 1711 | { |
2030c079 | 1712 | for (objfile *objfile : current_program_space->objfiles ()) |
cfc14b3a | 1713 | { |
b01c8410 PP |
1714 | struct dwarf2_fde_table *fde_table; |
1715 | struct dwarf2_fde **p_fde; | |
cfc14b3a | 1716 | CORE_ADDR offset; |
b01c8410 | 1717 | CORE_ADDR seek_pc; |
cfc14b3a | 1718 | |
924d79e2 | 1719 | fde_table = dwarf2_frame_objfile_data.get (objfile); |
b01c8410 | 1720 | if (fde_table == NULL) |
be391dca TT |
1721 | { |
1722 | dwarf2_build_frame_info (objfile); | |
924d79e2 | 1723 | fde_table = dwarf2_frame_objfile_data.get (objfile); |
be391dca TT |
1724 | } |
1725 | gdb_assert (fde_table != NULL); | |
1726 | ||
1727 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1728 | continue; |
1729 | ||
1730 | gdb_assert (objfile->section_offsets); | |
1731 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1732 | ||
b01c8410 PP |
1733 | gdb_assert (fde_table->num_entries > 0); |
1734 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1735 | continue; | |
1736 | ||
1737 | seek_pc = *pc - offset; | |
9a3c8263 SM |
1738 | p_fde = ((struct dwarf2_fde **) |
1739 | bsearch (&seek_pc, fde_table->entries, fde_table->num_entries, | |
1740 | sizeof (fde_table->entries[0]), bsearch_fde_cmp)); | |
b01c8410 PP |
1741 | if (p_fde != NULL) |
1742 | { | |
1743 | *pc = (*p_fde)->initial_location + offset; | |
ac56253d TT |
1744 | if (out_offset) |
1745 | *out_offset = offset; | |
b01c8410 PP |
1746 | return *p_fde; |
1747 | } | |
cfc14b3a | 1748 | } |
cfc14b3a MK |
1749 | return NULL; |
1750 | } | |
1751 | ||
b01c8410 | 1752 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1753 | static void |
b01c8410 | 1754 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1755 | { |
b01c8410 PP |
1756 | if (fde->address_range == 0) |
1757 | /* Discard useless FDEs. */ | |
1758 | return; | |
1759 | ||
1760 | fde_table->num_entries += 1; | |
224c3ddb SM |
1761 | fde_table->entries = XRESIZEVEC (struct dwarf2_fde *, fde_table->entries, |
1762 | fde_table->num_entries); | |
b01c8410 | 1763 | fde_table->entries[fde_table->num_entries - 1] = fde; |
cfc14b3a MK |
1764 | } |
1765 | ||
cfc14b3a | 1766 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1767 | |
8bd90839 FM |
1768 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1769 | or any of them. */ | |
1770 | ||
1771 | enum eh_frame_type | |
1772 | { | |
1773 | EH_CIE_TYPE_ID = 1 << 0, | |
1774 | EH_FDE_TYPE_ID = 1 << 1, | |
1775 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1776 | }; | |
1777 | ||
f664829e DE |
1778 | static const gdb_byte *decode_frame_entry (struct comp_unit *unit, |
1779 | const gdb_byte *start, | |
1780 | int eh_frame_p, | |
1781 | struct dwarf2_cie_table *cie_table, | |
1782 | struct dwarf2_fde_table *fde_table, | |
1783 | enum eh_frame_type entry_type); | |
8bd90839 FM |
1784 | |
1785 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1786 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1787 | |
f664829e DE |
1788 | static const gdb_byte * |
1789 | decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, | |
1790 | int eh_frame_p, | |
b01c8410 | 1791 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
1792 | struct dwarf2_fde_table *fde_table, |
1793 | enum eh_frame_type entry_type) | |
cfc14b3a | 1794 | { |
5e2b427d | 1795 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
f664829e | 1796 | const gdb_byte *buf, *end; |
723adb65 | 1797 | ULONGEST length; |
cfc14b3a | 1798 | unsigned int bytes_read; |
6896c0c7 RH |
1799 | int dwarf64_p; |
1800 | ULONGEST cie_id; | |
cfc14b3a | 1801 | ULONGEST cie_pointer; |
9fccedf7 DE |
1802 | int64_t sleb128; |
1803 | uint64_t uleb128; | |
cfc14b3a | 1804 | |
6896c0c7 | 1805 | buf = start; |
cfc14b3a MK |
1806 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1807 | buf += bytes_read; | |
723adb65 | 1808 | end = buf + (size_t) length; |
6896c0c7 | 1809 | |
cfc14b3a MK |
1810 | if (length == 0) |
1811 | return end; | |
1812 | ||
723adb65 SL |
1813 | /* Are we still within the section? */ |
1814 | if (end <= buf || end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1815 | return NULL; | |
1816 | ||
6896c0c7 RH |
1817 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1818 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1819 | |
6896c0c7 | 1820 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1821 | if (eh_frame_p) |
1822 | cie_id = 0; | |
1823 | else if (dwarf64_p) | |
1824 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1825 | else |
1826 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1827 | |
1828 | if (dwarf64_p) | |
1829 | { | |
1830 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1831 | buf += 8; | |
1832 | } | |
1833 | else | |
1834 | { | |
1835 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1836 | buf += 4; | |
1837 | } | |
1838 | ||
1839 | if (cie_pointer == cie_id) | |
1840 | { | |
1841 | /* This is a CIE. */ | |
1842 | struct dwarf2_cie *cie; | |
1843 | char *augmentation; | |
28ba0b33 | 1844 | unsigned int cie_version; |
cfc14b3a | 1845 | |
8bd90839 FM |
1846 | /* Check that a CIE was expected. */ |
1847 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1848 | error (_("Found a CIE when not expecting it.")); | |
1849 | ||
cfc14b3a MK |
1850 | /* Record the offset into the .debug_frame section of this CIE. */ |
1851 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1852 | ||
1853 | /* Check whether we've already read it. */ | |
b01c8410 | 1854 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1855 | return end; |
1856 | ||
8d749320 | 1857 | cie = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_cie); |
cfc14b3a MK |
1858 | cie->initial_instructions = NULL; |
1859 | cie->cie_pointer = cie_pointer; | |
1860 | ||
1861 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1862 | depends on the target address size. */ |
1863 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1864 | |
56c987f6 AO |
1865 | /* We'll determine the final value later, but we need to |
1866 | initialize it conservatively. */ | |
1867 | cie->signal_frame = 0; | |
1868 | ||
cfc14b3a | 1869 | /* Check version number. */ |
28ba0b33 | 1870 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1871 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1872 | return NULL; |
303b6f5d | 1873 | cie->version = cie_version; |
cfc14b3a MK |
1874 | buf += 1; |
1875 | ||
1876 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1877 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1878 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1879 | |
303b6f5d DJ |
1880 | /* Ignore armcc augmentations. We only use them for quirks, |
1881 | and that doesn't happen until later. */ | |
61012eef | 1882 | if (startswith (augmentation, "armcc")) |
303b6f5d DJ |
1883 | augmentation += strlen (augmentation); |
1884 | ||
cfc14b3a MK |
1885 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1886 | following the augmentation string, so it must be handled | |
1887 | first. */ | |
1888 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1889 | { | |
1890 | /* Skip. */ | |
5e2b427d | 1891 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1892 | augmentation += 2; |
1893 | } | |
1894 | ||
2dc7f7b3 TT |
1895 | if (cie->version >= 4) |
1896 | { | |
1897 | /* FIXME: check that this is the same as from the CU header. */ | |
1898 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1899 | ++buf; | |
1900 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1901 | ++buf; | |
1902 | } | |
1903 | else | |
1904 | { | |
8da614df | 1905 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1906 | cie->segment_size = 0; |
1907 | } | |
8da614df CV |
1908 | /* Address values in .eh_frame sections are defined to have the |
1909 | target's pointer size. Watchout: This breaks frame info for | |
1910 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1911 | section exists as well. */ |
8da614df CV |
1912 | if (eh_frame_p) |
1913 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1914 | else | |
1915 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1916 | |
f664829e DE |
1917 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1918 | if (buf == NULL) | |
1919 | return NULL; | |
1920 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1921 | |
f664829e DE |
1922 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1923 | if (buf == NULL) | |
1924 | return NULL; | |
1925 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1926 | |
28ba0b33 PB |
1927 | if (cie_version == 1) |
1928 | { | |
1929 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1930 | ++buf; |
28ba0b33 PB |
1931 | } |
1932 | else | |
f664829e DE |
1933 | { |
1934 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1935 | if (buf == NULL) | |
1936 | return NULL; | |
1937 | cie->return_address_register = uleb128; | |
1938 | } | |
1939 | ||
4fc771b8 | 1940 | cie->return_address_register |
5e2b427d | 1941 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1942 | cie->return_address_register, |
1943 | eh_frame_p); | |
4bf8967c | 1944 | |
7131cb6e RH |
1945 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1946 | if (cie->saw_z_augmentation) | |
cfc14b3a | 1947 | { |
b926417a | 1948 | uint64_t uleb_length; |
cfc14b3a | 1949 | |
b926417a | 1950 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e | 1951 | if (buf == NULL) |
6896c0c7 | 1952 | return NULL; |
b926417a | 1953 | cie->initial_instructions = buf + uleb_length; |
cfc14b3a MK |
1954 | augmentation++; |
1955 | } | |
1956 | ||
1957 | while (*augmentation) | |
1958 | { | |
1959 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1960 | if (*augmentation == 'L') | |
1961 | { | |
1962 | /* Skip. */ | |
1963 | buf++; | |
1964 | augmentation++; | |
1965 | } | |
1966 | ||
1967 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1968 | else if (*augmentation == 'R') | |
1969 | { | |
1970 | cie->encoding = *buf++; | |
1971 | augmentation++; | |
1972 | } | |
1973 | ||
1974 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1975 | else if (*augmentation == 'P') | |
1976 | { | |
1234d960 | 1977 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1978 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1979 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1980 | buf, &bytes_read, 0); |
f724bf08 | 1981 | buf += bytes_read; |
cfc14b3a MK |
1982 | augmentation++; |
1983 | } | |
1984 | ||
56c987f6 AO |
1985 | /* "S" indicates a signal frame, such that the return |
1986 | address must not be decremented to locate the call frame | |
1987 | info for the previous frame; it might even be the first | |
1988 | instruction of a function, so decrementing it would take | |
1989 | us to a different function. */ | |
1990 | else if (*augmentation == 'S') | |
1991 | { | |
1992 | cie->signal_frame = 1; | |
1993 | augmentation++; | |
1994 | } | |
1995 | ||
3e9a2e52 DJ |
1996 | /* Otherwise we have an unknown augmentation. Assume that either |
1997 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1998 | else |
1999 | { | |
3e9a2e52 DJ |
2000 | if (cie->initial_instructions) |
2001 | buf = cie->initial_instructions; | |
cfc14b3a MK |
2002 | break; |
2003 | } | |
2004 | } | |
2005 | ||
2006 | cie->initial_instructions = buf; | |
2007 | cie->end = end; | |
b01c8410 | 2008 | cie->unit = unit; |
cfc14b3a | 2009 | |
b01c8410 | 2010 | add_cie (cie_table, cie); |
cfc14b3a MK |
2011 | } |
2012 | else | |
2013 | { | |
2014 | /* This is a FDE. */ | |
2015 | struct dwarf2_fde *fde; | |
3e29f34a | 2016 | CORE_ADDR addr; |
cfc14b3a | 2017 | |
8bd90839 FM |
2018 | /* Check that an FDE was expected. */ |
2019 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
2020 | error (_("Found an FDE when not expecting it.")); | |
2021 | ||
6896c0c7 RH |
2022 | /* In an .eh_frame section, the CIE pointer is the delta between the |
2023 | address within the FDE where the CIE pointer is stored and the | |
2024 | address of the CIE. Convert it to an offset into the .eh_frame | |
2025 | section. */ | |
cfc14b3a MK |
2026 | if (eh_frame_p) |
2027 | { | |
cfc14b3a MK |
2028 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
2029 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
2030 | } | |
2031 | ||
6896c0c7 RH |
2032 | /* In either case, validate the result is still within the section. */ |
2033 | if (cie_pointer >= unit->dwarf_frame_size) | |
2034 | return NULL; | |
2035 | ||
8d749320 | 2036 | fde = XOBNEW (&unit->objfile->objfile_obstack, struct dwarf2_fde); |
b01c8410 | 2037 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2038 | if (fde->cie == NULL) |
2039 | { | |
2040 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
2041 | eh_frame_p, cie_table, fde_table, |
2042 | EH_CIE_TYPE_ID); | |
b01c8410 | 2043 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2044 | } |
2045 | ||
2046 | gdb_assert (fde->cie != NULL); | |
2047 | ||
3e29f34a MR |
2048 | addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
2049 | buf, &bytes_read, 0); | |
2050 | fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); | |
cfc14b3a MK |
2051 | buf += bytes_read; |
2052 | ||
2053 | fde->address_range = | |
ae0d2f24 | 2054 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 2055 | fde->cie->ptr_size, buf, &bytes_read, 0); |
3e29f34a MR |
2056 | addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); |
2057 | fde->address_range = addr - fde->initial_location; | |
cfc14b3a MK |
2058 | buf += bytes_read; |
2059 | ||
7131cb6e RH |
2060 | /* A 'z' augmentation in the CIE implies the presence of an |
2061 | augmentation field in the FDE as well. The only thing known | |
2062 | to be in here at present is the LSDA entry for EH. So we | |
2063 | can skip the whole thing. */ | |
2064 | if (fde->cie->saw_z_augmentation) | |
2065 | { | |
b926417a | 2066 | uint64_t uleb_length; |
7131cb6e | 2067 | |
b926417a | 2068 | buf = gdb_read_uleb128 (buf, end, &uleb_length); |
f664829e DE |
2069 | if (buf == NULL) |
2070 | return NULL; | |
b926417a | 2071 | buf += uleb_length; |
6896c0c7 RH |
2072 | if (buf > end) |
2073 | return NULL; | |
7131cb6e RH |
2074 | } |
2075 | ||
cfc14b3a MK |
2076 | fde->instructions = buf; |
2077 | fde->end = end; | |
2078 | ||
4bf8967c AS |
2079 | fde->eh_frame_p = eh_frame_p; |
2080 | ||
b01c8410 | 2081 | add_fde (fde_table, fde); |
cfc14b3a MK |
2082 | } |
2083 | ||
2084 | return end; | |
2085 | } | |
6896c0c7 | 2086 | |
8bd90839 FM |
2087 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2088 | expect an FDE or a CIE. */ | |
2089 | ||
f664829e DE |
2090 | static const gdb_byte * |
2091 | decode_frame_entry (struct comp_unit *unit, const gdb_byte *start, | |
2092 | int eh_frame_p, | |
b01c8410 | 2093 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
2094 | struct dwarf2_fde_table *fde_table, |
2095 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2096 | { |
2097 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2098 | const gdb_byte *ret; |
6896c0c7 RH |
2099 | ptrdiff_t start_offset; |
2100 | ||
2101 | while (1) | |
2102 | { | |
b01c8410 | 2103 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
8bd90839 | 2104 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2105 | if (ret != NULL) |
2106 | break; | |
2107 | ||
2108 | /* We have corrupt input data of some form. */ | |
2109 | ||
2110 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2111 | and mismatches wrt padding and alignment of debug sections. */ | |
2112 | /* Note that there is no requirement in the standard for any | |
2113 | alignment at all in the frame unwind sections. Testing for | |
2114 | alignment before trying to interpret data would be incorrect. | |
2115 | ||
2116 | However, GCC traditionally arranged for frame sections to be | |
2117 | sized such that the FDE length and CIE fields happen to be | |
2118 | aligned (in theory, for performance). This, unfortunately, | |
2119 | was done with .align directives, which had the side effect of | |
2120 | forcing the section to be aligned by the linker. | |
2121 | ||
2122 | This becomes a problem when you have some other producer that | |
2123 | creates frame sections that are not as strictly aligned. That | |
2124 | produces a hole in the frame info that gets filled by the | |
2125 | linker with zeros. | |
2126 | ||
2127 | The GCC behaviour is arguably a bug, but it's effectively now | |
2128 | part of the ABI, so we're now stuck with it, at least at the | |
2129 | object file level. A smart linker may decide, in the process | |
2130 | of compressing duplicate CIE information, that it can rewrite | |
2131 | the entire output section without this extra padding. */ | |
2132 | ||
2133 | start_offset = start - unit->dwarf_frame_buffer; | |
2134 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2135 | { | |
2136 | start += 4 - (start_offset & 3); | |
2137 | workaround = ALIGN4; | |
2138 | continue; | |
2139 | } | |
2140 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2141 | { | |
2142 | start += 8 - (start_offset & 7); | |
2143 | workaround = ALIGN8; | |
2144 | continue; | |
2145 | } | |
2146 | ||
2147 | /* Nothing left to try. Arrange to return as if we've consumed | |
2148 | the entire input section. Hopefully we'll get valid info from | |
2149 | the other of .debug_frame/.eh_frame. */ | |
2150 | workaround = FAIL; | |
2151 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2152 | break; | |
2153 | } | |
2154 | ||
2155 | switch (workaround) | |
2156 | { | |
2157 | case NONE: | |
2158 | break; | |
2159 | ||
2160 | case ALIGN4: | |
b98664d3 | 2161 | complaint (_("\ |
3e43a32a | 2162 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
2163 | unit->dwarf_frame_section->owner->filename, |
2164 | unit->dwarf_frame_section->name); | |
2165 | break; | |
2166 | ||
2167 | case ALIGN8: | |
b98664d3 | 2168 | complaint (_("\ |
3e43a32a | 2169 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
2170 | unit->dwarf_frame_section->owner->filename, |
2171 | unit->dwarf_frame_section->name); | |
2172 | break; | |
2173 | ||
2174 | default: | |
b98664d3 | 2175 | complaint (_("Corrupt data in %s:%s"), |
6896c0c7 RH |
2176 | unit->dwarf_frame_section->owner->filename, |
2177 | unit->dwarf_frame_section->name); | |
2178 | break; | |
2179 | } | |
2180 | ||
2181 | return ret; | |
2182 | } | |
cfc14b3a | 2183 | \f |
b01c8410 PP |
2184 | static int |
2185 | qsort_fde_cmp (const void *a, const void *b) | |
2186 | { | |
2187 | struct dwarf2_fde *aa = *(struct dwarf2_fde **)a; | |
2188 | struct dwarf2_fde *bb = *(struct dwarf2_fde **)b; | |
e5af178f | 2189 | |
b01c8410 | 2190 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2191 | { |
2192 | if (aa->address_range != bb->address_range | |
2193 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2194 | /* Linker bug, e.g. gold/10400. | |
2195 | Work around it by keeping stable sort order. */ | |
2196 | return (a < b) ? -1 : 1; | |
2197 | else | |
2198 | /* Put eh_frame entries after debug_frame ones. */ | |
2199 | return aa->eh_frame_p - bb->eh_frame_p; | |
2200 | } | |
b01c8410 PP |
2201 | |
2202 | return (aa->initial_location < bb->initial_location) ? -1 : 1; | |
2203 | } | |
2204 | ||
cfc14b3a MK |
2205 | void |
2206 | dwarf2_build_frame_info (struct objfile *objfile) | |
2207 | { | |
ae0d2f24 | 2208 | struct comp_unit *unit; |
f664829e | 2209 | const gdb_byte *frame_ptr; |
b01c8410 PP |
2210 | struct dwarf2_cie_table cie_table; |
2211 | struct dwarf2_fde_table fde_table; | |
be391dca | 2212 | struct dwarf2_fde_table *fde_table2; |
b01c8410 PP |
2213 | |
2214 | cie_table.num_entries = 0; | |
2215 | cie_table.entries = NULL; | |
2216 | ||
2217 | fde_table.num_entries = 0; | |
2218 | fde_table.entries = NULL; | |
cfc14b3a MK |
2219 | |
2220 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
e39db4db | 2221 | unit = XOBNEW (&objfile->objfile_obstack, comp_unit); |
ae0d2f24 UW |
2222 | unit->abfd = objfile->obfd; |
2223 | unit->objfile = objfile; | |
2224 | unit->dbase = 0; | |
2225 | unit->tbase = 0; | |
cfc14b3a | 2226 | |
d40102a1 | 2227 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2228 | { |
d40102a1 JB |
2229 | /* Do not read .eh_frame from separate file as they must be also |
2230 | present in the main file. */ | |
2231 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, | |
2232 | &unit->dwarf_frame_section, | |
2233 | &unit->dwarf_frame_buffer, | |
2234 | &unit->dwarf_frame_size); | |
2235 | if (unit->dwarf_frame_size) | |
b01c8410 | 2236 | { |
d40102a1 JB |
2237 | asection *got, *txt; |
2238 | ||
2239 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2240 | that is used for the i386/amd64 target, which currently is | |
2241 | the only target in GCC that supports/uses the | |
2242 | DW_EH_PE_datarel encoding. */ | |
2243 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2244 | if (got) | |
2245 | unit->dbase = got->vma; | |
2246 | ||
2247 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2248 | so far. */ | |
2249 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2250 | if (txt) | |
2251 | unit->tbase = txt->vma; | |
2252 | ||
a70b8144 | 2253 | try |
8bd90839 FM |
2254 | { |
2255 | frame_ptr = unit->dwarf_frame_buffer; | |
2256 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2257 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, | |
2258 | &cie_table, &fde_table, | |
2259 | EH_CIE_OR_FDE_TYPE_ID); | |
2260 | } | |
2261 | ||
230d2906 | 2262 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2263 | { |
2264 | warning (_("skipping .eh_frame info of %s: %s"), | |
3d6e9d23 | 2265 | objfile_name (objfile), e.what ()); |
8bd90839 FM |
2266 | |
2267 | if (fde_table.num_entries != 0) | |
2268 | { | |
2269 | xfree (fde_table.entries); | |
2270 | fde_table.entries = NULL; | |
2271 | fde_table.num_entries = 0; | |
2272 | } | |
2273 | /* The cie_table is discarded by the next if. */ | |
2274 | } | |
d40102a1 JB |
2275 | |
2276 | if (cie_table.num_entries != 0) | |
2277 | { | |
2278 | /* Reinit cie_table: debug_frame has different CIEs. */ | |
2279 | xfree (cie_table.entries); | |
2280 | cie_table.num_entries = 0; | |
2281 | cie_table.entries = NULL; | |
2282 | } | |
b01c8410 | 2283 | } |
cfc14b3a MK |
2284 | } |
2285 | ||
3017a003 | 2286 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dce234bc PP |
2287 | &unit->dwarf_frame_section, |
2288 | &unit->dwarf_frame_buffer, | |
2289 | &unit->dwarf_frame_size); | |
2290 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2291 | { |
8bd90839 FM |
2292 | int num_old_fde_entries = fde_table.num_entries; |
2293 | ||
a70b8144 | 2294 | try |
8bd90839 FM |
2295 | { |
2296 | frame_ptr = unit->dwarf_frame_buffer; | |
2297 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2298 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, | |
2299 | &cie_table, &fde_table, | |
2300 | EH_CIE_OR_FDE_TYPE_ID); | |
2301 | } | |
230d2906 | 2302 | catch (const gdb_exception_error &e) |
8bd90839 FM |
2303 | { |
2304 | warning (_("skipping .debug_frame info of %s: %s"), | |
3d6e9d23 | 2305 | objfile_name (objfile), e.what ()); |
8bd90839 FM |
2306 | |
2307 | if (fde_table.num_entries != 0) | |
2308 | { | |
2309 | fde_table.num_entries = num_old_fde_entries; | |
2310 | if (num_old_fde_entries == 0) | |
2311 | { | |
2312 | xfree (fde_table.entries); | |
2313 | fde_table.entries = NULL; | |
2314 | } | |
2315 | else | |
2316 | { | |
224c3ddb SM |
2317 | fde_table.entries |
2318 | = XRESIZEVEC (struct dwarf2_fde *, fde_table.entries, | |
2319 | fde_table.num_entries); | |
8bd90839 FM |
2320 | } |
2321 | } | |
2322 | fde_table.num_entries = num_old_fde_entries; | |
2323 | /* The cie_table is discarded by the next if. */ | |
2324 | } | |
b01c8410 PP |
2325 | } |
2326 | ||
2327 | /* Discard the cie_table, it is no longer needed. */ | |
2328 | if (cie_table.num_entries != 0) | |
2329 | { | |
2330 | xfree (cie_table.entries); | |
2331 | cie_table.entries = NULL; /* Paranoia. */ | |
2332 | cie_table.num_entries = 0; /* Paranoia. */ | |
2333 | } | |
2334 | ||
be391dca | 2335 | /* Copy fde_table to obstack: it is needed at runtime. */ |
8d749320 | 2336 | fde_table2 = XOBNEW (&objfile->objfile_obstack, struct dwarf2_fde_table); |
be391dca TT |
2337 | |
2338 | if (fde_table.num_entries == 0) | |
2339 | { | |
2340 | fde_table2->entries = NULL; | |
2341 | fde_table2->num_entries = 0; | |
2342 | } | |
2343 | else | |
b01c8410 | 2344 | { |
875cdfbb PA |
2345 | struct dwarf2_fde *fde_prev = NULL; |
2346 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2347 | int i; | |
b01c8410 PP |
2348 | |
2349 | /* Prepare FDE table for lookups. */ | |
2350 | qsort (fde_table.entries, fde_table.num_entries, | |
2351 | sizeof (fde_table.entries[0]), qsort_fde_cmp); | |
2352 | ||
875cdfbb PA |
2353 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2354 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2355 | ranges because there's no relocation there. It's (offset, | |
2356 | length), not (start, end). On targets where address zero is | |
2357 | just another valid address this can be a problem, since the | |
2358 | FDEs appear to be non-empty in the output --- we could pick | |
2359 | out the wrong FDE. To work around this, when overlaps are | |
2360 | detected, we prefer FDEs that do not start at zero. | |
2361 | ||
2362 | Start by finding the first FDE with non-zero start. Below | |
2363 | we'll discard all FDEs that start at zero and overlap this | |
2364 | one. */ | |
2365 | for (i = 0; i < fde_table.num_entries; i++) | |
2366 | { | |
2367 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2368 | |
875cdfbb PA |
2369 | if (fde->initial_location != 0) |
2370 | { | |
2371 | first_non_zero_fde = fde; | |
2372 | break; | |
2373 | } | |
2374 | } | |
2375 | ||
2376 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2377 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2378 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2379 | fde_table2->num_entries = 0; |
875cdfbb PA |
2380 | for (i = 0; i < fde_table.num_entries; i++) |
2381 | { | |
2382 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2383 | ||
2384 | if (fde->initial_location == 0 | |
2385 | && first_non_zero_fde != NULL | |
2386 | && (first_non_zero_fde->initial_location | |
2387 | < fde->initial_location + fde->address_range)) | |
2388 | continue; | |
2389 | ||
2390 | if (fde_prev != NULL | |
2391 | && fde_prev->initial_location == fde->initial_location) | |
2392 | continue; | |
2393 | ||
2394 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2395 | sizeof (fde_table.entries[0])); | |
2396 | ++fde_table2->num_entries; | |
2397 | fde_prev = fde; | |
2398 | } | |
224c3ddb SM |
2399 | fde_table2->entries |
2400 | = (struct dwarf2_fde **) obstack_finish (&objfile->objfile_obstack); | |
b01c8410 PP |
2401 | |
2402 | /* Discard the original fde_table. */ | |
2403 | xfree (fde_table.entries); | |
cfc14b3a | 2404 | } |
be391dca | 2405 | |
924d79e2 | 2406 | dwarf2_frame_objfile_data.set (objfile, fde_table2); |
cfc14b3a | 2407 | } |
0d0e1a63 | 2408 | |
3c3bb058 AB |
2409 | /* Handle 'maintenance show dwarf unwinders'. */ |
2410 | ||
2411 | static void | |
2412 | show_dwarf_unwinders_enabled_p (struct ui_file *file, int from_tty, | |
2413 | struct cmd_list_element *c, | |
2414 | const char *value) | |
2415 | { | |
2416 | fprintf_filtered (file, | |
2417 | _("The DWARF stack unwinders are currently %s.\n"), | |
2418 | value); | |
2419 | } | |
2420 | ||
0d0e1a63 MK |
2421 | void |
2422 | _initialize_dwarf2_frame (void) | |
2423 | { | |
030f20e1 | 2424 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
1c90d9f0 | 2425 | |
3c3bb058 AB |
2426 | add_setshow_boolean_cmd ("unwinders", class_obscure, |
2427 | &dwarf2_frame_unwinders_enabled_p , _("\ | |
2428 | Set whether the DWARF stack frame unwinders are used."), _("\ | |
2429 | Show whether the DWARF stack frame unwinders are used."), _("\ | |
2430 | When enabled the DWARF stack frame unwinders can be used for architectures\n\ | |
2431 | that support the DWARF unwinders. Enabling the DWARF unwinders for an\n\ | |
2432 | architecture that doesn't support them will have no effect."), | |
2433 | NULL, | |
2434 | show_dwarf_unwinders_enabled_p, | |
2435 | &set_dwarf_cmdlist, | |
2436 | &show_dwarf_cmdlist); | |
2437 | ||
1c90d9f0 | 2438 | #if GDB_SELF_TEST |
1526853e SM |
2439 | selftests::register_test_foreach_arch ("execute_cfa_program", |
2440 | selftests::execute_cfa_program_test); | |
1c90d9f0 | 2441 | #endif |
0d0e1a63 | 2442 | } |