Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
ecd75fc8 | 3 | Copyright (C) 2003-2014 Free Software Foundation, Inc. |
cfc14b3a MK |
4 | |
5 | Contributed by Mark Kettenis. | |
6 | ||
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
cfc14b3a MK |
12 | (at your option) any later version. |
13 | ||
14 | This program is distributed in the hope that it will be useful, | |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
cfc14b3a MK |
21 | |
22 | #include "defs.h" | |
23 | #include "dwarf2expr.h" | |
fa8f86ff | 24 | #include "dwarf2.h" |
cfc14b3a MK |
25 | #include "frame.h" |
26 | #include "frame-base.h" | |
27 | #include "frame-unwind.h" | |
28 | #include "gdbcore.h" | |
29 | #include "gdbtypes.h" | |
30 | #include "symtab.h" | |
31 | #include "objfiles.h" | |
32 | #include "regcache.h" | |
f2da6b3a | 33 | #include "value.h" |
0b722aec | 34 | #include "record.h" |
cfc14b3a MK |
35 | |
36 | #include "gdb_assert.h" | |
0e9f083f | 37 | #include <string.h> |
cfc14b3a | 38 | |
6896c0c7 | 39 | #include "complaints.h" |
cfc14b3a | 40 | #include "dwarf2-frame.h" |
9f6f94ff TT |
41 | #include "ax.h" |
42 | #include "dwarf2loc.h" | |
8fbca658 | 43 | #include "exceptions.h" |
111c6489 | 44 | #include "dwarf2-frame-tailcall.h" |
cfc14b3a | 45 | |
ae0d2f24 UW |
46 | struct comp_unit; |
47 | ||
cfc14b3a MK |
48 | /* Call Frame Information (CFI). */ |
49 | ||
50 | /* Common Information Entry (CIE). */ | |
51 | ||
52 | struct dwarf2_cie | |
53 | { | |
ae0d2f24 UW |
54 | /* Computation Unit for this CIE. */ |
55 | struct comp_unit *unit; | |
56 | ||
cfc14b3a MK |
57 | /* Offset into the .debug_frame section where this CIE was found. |
58 | Used to identify this CIE. */ | |
59 | ULONGEST cie_pointer; | |
60 | ||
61 | /* Constant that is factored out of all advance location | |
62 | instructions. */ | |
63 | ULONGEST code_alignment_factor; | |
64 | ||
65 | /* Constants that is factored out of all offset instructions. */ | |
66 | LONGEST data_alignment_factor; | |
67 | ||
68 | /* Return address column. */ | |
69 | ULONGEST return_address_register; | |
70 | ||
71 | /* Instruction sequence to initialize a register set. */ | |
f664829e DE |
72 | const gdb_byte *initial_instructions; |
73 | const gdb_byte *end; | |
cfc14b3a | 74 | |
303b6f5d DJ |
75 | /* Saved augmentation, in case it's needed later. */ |
76 | char *augmentation; | |
77 | ||
cfc14b3a | 78 | /* Encoding of addresses. */ |
852483bc | 79 | gdb_byte encoding; |
cfc14b3a | 80 | |
ae0d2f24 UW |
81 | /* Target address size in bytes. */ |
82 | int addr_size; | |
83 | ||
0963b4bd | 84 | /* Target pointer size in bytes. */ |
8da614df CV |
85 | int ptr_size; |
86 | ||
7131cb6e RH |
87 | /* True if a 'z' augmentation existed. */ |
88 | unsigned char saw_z_augmentation; | |
89 | ||
56c987f6 AO |
90 | /* True if an 'S' augmentation existed. */ |
91 | unsigned char signal_frame; | |
92 | ||
303b6f5d DJ |
93 | /* The version recorded in the CIE. */ |
94 | unsigned char version; | |
2dc7f7b3 TT |
95 | |
96 | /* The segment size. */ | |
97 | unsigned char segment_size; | |
b01c8410 | 98 | }; |
303b6f5d | 99 | |
b01c8410 PP |
100 | struct dwarf2_cie_table |
101 | { | |
102 | int num_entries; | |
103 | struct dwarf2_cie **entries; | |
cfc14b3a MK |
104 | }; |
105 | ||
106 | /* Frame Description Entry (FDE). */ | |
107 | ||
108 | struct dwarf2_fde | |
109 | { | |
110 | /* CIE for this FDE. */ | |
111 | struct dwarf2_cie *cie; | |
112 | ||
113 | /* First location associated with this FDE. */ | |
114 | CORE_ADDR initial_location; | |
115 | ||
116 | /* Number of bytes of program instructions described by this FDE. */ | |
117 | CORE_ADDR address_range; | |
118 | ||
119 | /* Instruction sequence. */ | |
f664829e DE |
120 | const gdb_byte *instructions; |
121 | const gdb_byte *end; | |
cfc14b3a | 122 | |
4bf8967c AS |
123 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
124 | section. */ | |
125 | unsigned char eh_frame_p; | |
b01c8410 | 126 | }; |
4bf8967c | 127 | |
b01c8410 PP |
128 | struct dwarf2_fde_table |
129 | { | |
130 | int num_entries; | |
131 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
132 | }; |
133 | ||
ae0d2f24 UW |
134 | /* A minimal decoding of DWARF2 compilation units. We only decode |
135 | what's needed to get to the call frame information. */ | |
136 | ||
137 | struct comp_unit | |
138 | { | |
139 | /* Keep the bfd convenient. */ | |
140 | bfd *abfd; | |
141 | ||
142 | struct objfile *objfile; | |
143 | ||
ae0d2f24 | 144 | /* Pointer to the .debug_frame section loaded into memory. */ |
d521ce57 | 145 | const gdb_byte *dwarf_frame_buffer; |
ae0d2f24 UW |
146 | |
147 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 148 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
149 | |
150 | /* Pointer to the .debug_frame section. */ | |
151 | asection *dwarf_frame_section; | |
152 | ||
153 | /* Base for DW_EH_PE_datarel encodings. */ | |
154 | bfd_vma dbase; | |
155 | ||
156 | /* Base for DW_EH_PE_textrel encodings. */ | |
157 | bfd_vma tbase; | |
158 | }; | |
159 | ||
ac56253d TT |
160 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
161 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
162 | |
163 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
164 | int eh_frame_p); | |
ae0d2f24 UW |
165 | |
166 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 167 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
168 | unsigned int *bytes_read_ptr, |
169 | CORE_ADDR func_base); | |
cfc14b3a MK |
170 | \f |
171 | ||
172 | /* Structure describing a frame state. */ | |
173 | ||
174 | struct dwarf2_frame_state | |
175 | { | |
176 | /* Each register save state can be described in terms of a CFA slot, | |
177 | another register, or a location expression. */ | |
178 | struct dwarf2_frame_state_reg_info | |
179 | { | |
05cbe71a | 180 | struct dwarf2_frame_state_reg *reg; |
cfc14b3a MK |
181 | int num_regs; |
182 | ||
2fd481e1 PP |
183 | LONGEST cfa_offset; |
184 | ULONGEST cfa_reg; | |
185 | enum { | |
186 | CFA_UNSET, | |
187 | CFA_REG_OFFSET, | |
188 | CFA_EXP | |
189 | } cfa_how; | |
0d45f56e | 190 | const gdb_byte *cfa_exp; |
2fd481e1 | 191 | |
cfc14b3a MK |
192 | /* Used to implement DW_CFA_remember_state. */ |
193 | struct dwarf2_frame_state_reg_info *prev; | |
194 | } regs; | |
195 | ||
cfc14b3a MK |
196 | /* The PC described by the current frame state. */ |
197 | CORE_ADDR pc; | |
198 | ||
199 | /* Initial register set from the CIE. | |
200 | Used to implement DW_CFA_restore. */ | |
201 | struct dwarf2_frame_state_reg_info initial; | |
202 | ||
203 | /* The information we care about from the CIE. */ | |
204 | LONGEST data_align; | |
205 | ULONGEST code_align; | |
206 | ULONGEST retaddr_column; | |
303b6f5d DJ |
207 | |
208 | /* Flags for known producer quirks. */ | |
209 | ||
210 | /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa | |
211 | and DW_CFA_def_cfa_offset takes a factored offset. */ | |
212 | int armcc_cfa_offsets_sf; | |
213 | ||
214 | /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that | |
215 | the CFA is defined as REG - OFFSET rather than REG + OFFSET. */ | |
216 | int armcc_cfa_offsets_reversed; | |
cfc14b3a MK |
217 | }; |
218 | ||
219 | /* Store the length the expression for the CFA in the `cfa_reg' field, | |
220 | which is unused in that case. */ | |
221 | #define cfa_exp_len cfa_reg | |
222 | ||
f57d151a | 223 | /* Assert that the register set RS is large enough to store gdbarch_num_regs |
cfc14b3a MK |
224 | columns. If necessary, enlarge the register set. */ |
225 | ||
226 | static void | |
227 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, | |
228 | int num_regs) | |
229 | { | |
230 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
231 | ||
232 | if (num_regs <= rs->num_regs) | |
233 | return; | |
234 | ||
235 | rs->reg = (struct dwarf2_frame_state_reg *) | |
236 | xrealloc (rs->reg, num_regs * size); | |
237 | ||
238 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 239 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
240 | rs->num_regs = num_regs; |
241 | } | |
242 | ||
243 | /* Copy the register columns in register set RS into newly allocated | |
244 | memory and return a pointer to this newly created copy. */ | |
245 | ||
246 | static struct dwarf2_frame_state_reg * | |
247 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
248 | { | |
d10891d4 | 249 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
250 | struct dwarf2_frame_state_reg *reg; |
251 | ||
252 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
253 | memcpy (reg, rs->reg, size); | |
254 | ||
255 | return reg; | |
256 | } | |
257 | ||
258 | /* Release the memory allocated to register set RS. */ | |
259 | ||
260 | static void | |
261 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
262 | { | |
263 | if (rs) | |
264 | { | |
265 | dwarf2_frame_state_free_regs (rs->prev); | |
266 | ||
267 | xfree (rs->reg); | |
268 | xfree (rs); | |
269 | } | |
270 | } | |
271 | ||
272 | /* Release the memory allocated to the frame state FS. */ | |
273 | ||
274 | static void | |
275 | dwarf2_frame_state_free (void *p) | |
276 | { | |
277 | struct dwarf2_frame_state *fs = p; | |
278 | ||
279 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
280 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
281 | xfree (fs->initial.reg); | |
282 | xfree (fs->regs.reg); | |
283 | xfree (fs); | |
284 | } | |
285 | \f | |
286 | ||
287 | /* Helper functions for execute_stack_op. */ | |
288 | ||
289 | static CORE_ADDR | |
b1370418 | 290 | read_addr_from_reg (void *baton, int reg) |
cfc14b3a | 291 | { |
4a4e5149 DJ |
292 | struct frame_info *this_frame = (struct frame_info *) baton; |
293 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
cfc14b3a | 294 | int regnum; |
852483bc | 295 | gdb_byte *buf; |
cfc14b3a | 296 | |
ad010def | 297 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); |
cfc14b3a | 298 | |
852483bc | 299 | buf = alloca (register_size (gdbarch, regnum)); |
4a4e5149 | 300 | get_frame_register (this_frame, regnum, buf); |
f2da6b3a | 301 | |
4b4589ad | 302 | return unpack_pointer (register_type (gdbarch, regnum), buf); |
cfc14b3a MK |
303 | } |
304 | ||
0acf8b65 JB |
305 | /* Implement struct dwarf_expr_context_funcs' "get_reg_value" callback. */ |
306 | ||
307 | static struct value * | |
308 | get_reg_value (void *baton, struct type *type, int reg) | |
309 | { | |
310 | struct frame_info *this_frame = (struct frame_info *) baton; | |
311 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
312 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); | |
313 | ||
314 | return value_from_register (type, regnum, this_frame); | |
315 | } | |
316 | ||
cfc14b3a | 317 | static void |
852483bc | 318 | read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
cfc14b3a MK |
319 | { |
320 | read_memory (addr, buf, len); | |
321 | } | |
322 | ||
a6a5a945 LM |
323 | /* Execute the required actions for both the DW_CFA_restore and |
324 | DW_CFA_restore_extended instructions. */ | |
325 | static void | |
326 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
327 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
328 | { | |
329 | ULONGEST reg; | |
330 | ||
331 | gdb_assert (fs->initial.reg); | |
332 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); | |
333 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
334 | ||
335 | /* Check if this register was explicitly initialized in the | |
336 | CIE initial instructions. If not, default the rule to | |
337 | UNSPECIFIED. */ | |
338 | if (reg < fs->initial.num_regs) | |
339 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
340 | else | |
341 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
342 | ||
343 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
344 | complaint (&symfile_complaints, _("\ | |
345 | incomplete CFI data; DW_CFA_restore unspecified\n\ | |
5af949e3 | 346 | register %s (#%d) at %s"), |
a6a5a945 LM |
347 | gdbarch_register_name |
348 | (gdbarch, gdbarch_dwarf2_reg_to_regnum (gdbarch, reg)), | |
349 | gdbarch_dwarf2_reg_to_regnum (gdbarch, reg), | |
5af949e3 | 350 | paddress (gdbarch, fs->pc)); |
a6a5a945 LM |
351 | } |
352 | ||
9e8b7a03 JK |
353 | /* Virtual method table for execute_stack_op below. */ |
354 | ||
355 | static const struct dwarf_expr_context_funcs dwarf2_frame_ctx_funcs = | |
356 | { | |
b1370418 | 357 | read_addr_from_reg, |
0acf8b65 | 358 | get_reg_value, |
9e8b7a03 | 359 | read_mem, |
523f3620 JK |
360 | ctx_no_get_frame_base, |
361 | ctx_no_get_frame_cfa, | |
362 | ctx_no_get_frame_pc, | |
363 | ctx_no_get_tls_address, | |
364 | ctx_no_dwarf_call, | |
8e3b41a9 | 365 | ctx_no_get_base_type, |
3019eac3 DE |
366 | ctx_no_push_dwarf_reg_entry_value, |
367 | ctx_no_get_addr_index | |
9e8b7a03 JK |
368 | }; |
369 | ||
cfc14b3a | 370 | static CORE_ADDR |
0d45f56e | 371 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
372 | CORE_ADDR offset, struct frame_info *this_frame, |
373 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a MK |
374 | { |
375 | struct dwarf_expr_context *ctx; | |
376 | CORE_ADDR result; | |
4a227398 | 377 | struct cleanup *old_chain; |
cfc14b3a MK |
378 | |
379 | ctx = new_dwarf_expr_context (); | |
4a227398 | 380 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
72fc29ff | 381 | make_cleanup_value_free_to_mark (value_mark ()); |
4a227398 | 382 | |
f7fd4728 | 383 | ctx->gdbarch = get_frame_arch (this_frame); |
ae0d2f24 | 384 | ctx->addr_size = addr_size; |
181cebd4 | 385 | ctx->ref_addr_size = -1; |
ac56253d | 386 | ctx->offset = offset; |
4a4e5149 | 387 | ctx->baton = this_frame; |
9e8b7a03 | 388 | ctx->funcs = &dwarf2_frame_ctx_funcs; |
cfc14b3a | 389 | |
8a9b8146 | 390 | dwarf_expr_push_address (ctx, initial, initial_in_stack_memory); |
cfc14b3a | 391 | dwarf_expr_eval (ctx, exp, len); |
cfc14b3a | 392 | |
f2c7657e UW |
393 | if (ctx->location == DWARF_VALUE_MEMORY) |
394 | result = dwarf_expr_fetch_address (ctx, 0); | |
395 | else if (ctx->location == DWARF_VALUE_REGISTER) | |
b1370418 JB |
396 | result = read_addr_from_reg (this_frame, |
397 | value_as_long (dwarf_expr_fetch (ctx, 0))); | |
f2c7657e | 398 | else |
cec03d70 TT |
399 | { |
400 | /* This is actually invalid DWARF, but if we ever do run across | |
401 | it somehow, we might as well support it. So, instead, report | |
402 | it as unimplemented. */ | |
3e43a32a MS |
403 | error (_("\ |
404 | Not implemented: computing unwound register using explicit value operator")); | |
cec03d70 | 405 | } |
cfc14b3a | 406 | |
4a227398 | 407 | do_cleanups (old_chain); |
cfc14b3a MK |
408 | |
409 | return result; | |
410 | } | |
411 | \f | |
412 | ||
111c6489 JK |
413 | /* Execute FDE program from INSN_PTR possibly up to INSN_END or up to inferior |
414 | PC. Modify FS state accordingly. Return current INSN_PTR where the | |
415 | execution has stopped, one can resume it on the next call. */ | |
416 | ||
417 | static const gdb_byte * | |
0d45f56e | 418 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
9f6f94ff TT |
419 | const gdb_byte *insn_end, struct gdbarch *gdbarch, |
420 | CORE_ADDR pc, struct dwarf2_frame_state *fs) | |
cfc14b3a | 421 | { |
ae0d2f24 | 422 | int eh_frame_p = fde->eh_frame_p; |
507a579c | 423 | unsigned int bytes_read; |
e17a4113 | 424 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
425 | |
426 | while (insn_ptr < insn_end && fs->pc <= pc) | |
427 | { | |
852483bc | 428 | gdb_byte insn = *insn_ptr++; |
9fccedf7 DE |
429 | uint64_t utmp, reg; |
430 | int64_t offset; | |
cfc14b3a MK |
431 | |
432 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
433 | fs->pc += (insn & 0x3f) * fs->code_align; | |
434 | else if ((insn & 0xc0) == DW_CFA_offset) | |
435 | { | |
436 | reg = insn & 0x3f; | |
4fc771b8 | 437 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 438 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
439 | offset = utmp * fs->data_align; |
440 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 441 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
442 | fs->regs.reg[reg].loc.offset = offset; |
443 | } | |
444 | else if ((insn & 0xc0) == DW_CFA_restore) | |
445 | { | |
cfc14b3a | 446 | reg = insn & 0x3f; |
a6a5a945 | 447 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
448 | } |
449 | else | |
450 | { | |
451 | switch (insn) | |
452 | { | |
453 | case DW_CFA_set_loc: | |
ae0d2f24 | 454 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 455 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
456 | &bytes_read, fde->initial_location); |
457 | /* Apply the objfile offset for relocatable objects. */ | |
458 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
459 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
460 | insn_ptr += bytes_read; |
461 | break; | |
462 | ||
463 | case DW_CFA_advance_loc1: | |
e17a4113 | 464 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
465 | fs->pc += utmp * fs->code_align; |
466 | insn_ptr++; | |
467 | break; | |
468 | case DW_CFA_advance_loc2: | |
e17a4113 | 469 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
470 | fs->pc += utmp * fs->code_align; |
471 | insn_ptr += 2; | |
472 | break; | |
473 | case DW_CFA_advance_loc4: | |
e17a4113 | 474 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
475 | fs->pc += utmp * fs->code_align; |
476 | insn_ptr += 4; | |
477 | break; | |
478 | ||
479 | case DW_CFA_offset_extended: | |
f664829e | 480 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 481 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 482 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
483 | offset = utmp * fs->data_align; |
484 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 485 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
486 | fs->regs.reg[reg].loc.offset = offset; |
487 | break; | |
488 | ||
489 | case DW_CFA_restore_extended: | |
f664829e | 490 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 491 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
492 | break; |
493 | ||
494 | case DW_CFA_undefined: | |
f664829e | 495 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 496 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 497 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 498 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
499 | break; |
500 | ||
501 | case DW_CFA_same_value: | |
f664829e | 502 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 503 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 504 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 505 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
506 | break; |
507 | ||
508 | case DW_CFA_register: | |
f664829e | 509 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 510 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 511 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 512 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 513 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 514 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
515 | fs->regs.reg[reg].loc.reg = utmp; |
516 | break; | |
517 | ||
518 | case DW_CFA_remember_state: | |
519 | { | |
520 | struct dwarf2_frame_state_reg_info *new_rs; | |
521 | ||
70ba0933 | 522 | new_rs = XNEW (struct dwarf2_frame_state_reg_info); |
cfc14b3a MK |
523 | *new_rs = fs->regs; |
524 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
525 | fs->regs.prev = new_rs; | |
526 | } | |
527 | break; | |
528 | ||
529 | case DW_CFA_restore_state: | |
530 | { | |
531 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
532 | ||
50ea7769 MK |
533 | if (old_rs == NULL) |
534 | { | |
e2e0b3e5 | 535 | complaint (&symfile_complaints, _("\ |
5af949e3 UW |
536 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
537 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
538 | } |
539 | else | |
540 | { | |
541 | xfree (fs->regs.reg); | |
542 | fs->regs = *old_rs; | |
543 | xfree (old_rs); | |
544 | } | |
cfc14b3a MK |
545 | } |
546 | break; | |
547 | ||
548 | case DW_CFA_def_cfa: | |
f664829e DE |
549 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
550 | fs->regs.cfa_reg = reg; | |
551 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); | |
303b6f5d DJ |
552 | |
553 | if (fs->armcc_cfa_offsets_sf) | |
554 | utmp *= fs->data_align; | |
555 | ||
2fd481e1 PP |
556 | fs->regs.cfa_offset = utmp; |
557 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
558 | break; |
559 | ||
560 | case DW_CFA_def_cfa_register: | |
f664829e DE |
561 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
562 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 PP |
563 | eh_frame_p); |
564 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
565 | break; |
566 | ||
567 | case DW_CFA_def_cfa_offset: | |
f664829e | 568 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
569 | |
570 | if (fs->armcc_cfa_offsets_sf) | |
571 | utmp *= fs->data_align; | |
572 | ||
2fd481e1 | 573 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
574 | /* cfa_how deliberately not set. */ |
575 | break; | |
576 | ||
a8504492 MK |
577 | case DW_CFA_nop: |
578 | break; | |
579 | ||
cfc14b3a | 580 | case DW_CFA_def_cfa_expression: |
f664829e DE |
581 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
582 | fs->regs.cfa_exp_len = utmp; | |
2fd481e1 PP |
583 | fs->regs.cfa_exp = insn_ptr; |
584 | fs->regs.cfa_how = CFA_EXP; | |
585 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
586 | break; |
587 | ||
588 | case DW_CFA_expression: | |
f664829e | 589 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 590 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 591 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 592 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
593 | fs->regs.reg[reg].loc.exp = insn_ptr; |
594 | fs->regs.reg[reg].exp_len = utmp; | |
05cbe71a | 595 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
596 | insn_ptr += utmp; |
597 | break; | |
598 | ||
a8504492 | 599 | case DW_CFA_offset_extended_sf: |
f664829e | 600 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 601 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
f664829e | 602 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 603 | offset *= fs->data_align; |
a8504492 | 604 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 605 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
606 | fs->regs.reg[reg].loc.offset = offset; |
607 | break; | |
608 | ||
46ea248b | 609 | case DW_CFA_val_offset: |
f664829e | 610 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 611 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 612 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
613 | offset = utmp * fs->data_align; |
614 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
615 | fs->regs.reg[reg].loc.offset = offset; | |
616 | break; | |
617 | ||
618 | case DW_CFA_val_offset_sf: | |
f664829e | 619 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 620 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 621 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
46ea248b AO |
622 | offset *= fs->data_align; |
623 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
624 | fs->regs.reg[reg].loc.offset = offset; | |
625 | break; | |
626 | ||
627 | case DW_CFA_val_expression: | |
f664829e | 628 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
46ea248b | 629 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
f664829e | 630 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
46ea248b AO |
631 | fs->regs.reg[reg].loc.exp = insn_ptr; |
632 | fs->regs.reg[reg].exp_len = utmp; | |
633 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; | |
634 | insn_ptr += utmp; | |
635 | break; | |
636 | ||
a8504492 | 637 | case DW_CFA_def_cfa_sf: |
f664829e DE |
638 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
639 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, reg, | |
2fd481e1 | 640 | eh_frame_p); |
f664829e | 641 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
642 | fs->regs.cfa_offset = offset * fs->data_align; |
643 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
644 | break; |
645 | ||
646 | case DW_CFA_def_cfa_offset_sf: | |
f664829e | 647 | insn_ptr = safe_read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 | 648 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 649 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
650 | break; |
651 | ||
a77f4086 MK |
652 | case DW_CFA_GNU_window_save: |
653 | /* This is SPARC-specific code, and contains hard-coded | |
654 | constants for the register numbering scheme used by | |
655 | GCC. Rather than having a architecture-specific | |
656 | operation that's only ever used by a single | |
657 | architecture, we provide the implementation here. | |
658 | Incidentally that's what GCC does too in its | |
659 | unwinder. */ | |
660 | { | |
4a4e5149 | 661 | int size = register_size (gdbarch, 0); |
9a619af0 | 662 | |
a77f4086 MK |
663 | dwarf2_frame_state_alloc_regs (&fs->regs, 32); |
664 | for (reg = 8; reg < 16; reg++) | |
665 | { | |
666 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; | |
667 | fs->regs.reg[reg].loc.reg = reg + 16; | |
668 | } | |
669 | for (reg = 16; reg < 32; reg++) | |
670 | { | |
671 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
672 | fs->regs.reg[reg].loc.offset = (reg - 16) * size; | |
673 | } | |
674 | } | |
675 | break; | |
676 | ||
cfc14b3a MK |
677 | case DW_CFA_GNU_args_size: |
678 | /* Ignored. */ | |
f664829e | 679 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
cfc14b3a MK |
680 | break; |
681 | ||
58894217 | 682 | case DW_CFA_GNU_negative_offset_extended: |
f664829e | 683 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, ®); |
4fc771b8 | 684 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
507a579c PA |
685 | insn_ptr = safe_read_uleb128 (insn_ptr, insn_end, &utmp); |
686 | offset = utmp * fs->data_align; | |
58894217 JK |
687 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
688 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
689 | fs->regs.reg[reg].loc.offset = -offset; | |
690 | break; | |
691 | ||
cfc14b3a | 692 | default: |
3e43a32a MS |
693 | internal_error (__FILE__, __LINE__, |
694 | _("Unknown CFI encountered.")); | |
cfc14b3a MK |
695 | } |
696 | } | |
697 | } | |
698 | ||
111c6489 JK |
699 | if (fs->initial.reg == NULL) |
700 | { | |
701 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
702 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
703 | fs->regs.prev = NULL; | |
704 | } | |
705 | ||
706 | return insn_ptr; | |
cfc14b3a | 707 | } |
8f22cb90 | 708 | \f |
cfc14b3a | 709 | |
8f22cb90 | 710 | /* Architecture-specific operations. */ |
cfc14b3a | 711 | |
8f22cb90 MK |
712 | /* Per-architecture data key. */ |
713 | static struct gdbarch_data *dwarf2_frame_data; | |
714 | ||
715 | struct dwarf2_frame_ops | |
716 | { | |
717 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
718 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
719 | struct frame_info *); | |
3ed09a32 | 720 | |
4a4e5149 | 721 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 722 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 723 | |
4fc771b8 DJ |
724 | /* Convert .eh_frame register number to DWARF register number, or |
725 | adjust .debug_frame register number. */ | |
726 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
727 | }; |
728 | ||
8f22cb90 MK |
729 | /* Default architecture-specific register state initialization |
730 | function. */ | |
731 | ||
732 | static void | |
733 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 734 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 735 | struct frame_info *this_frame) |
8f22cb90 MK |
736 | { |
737 | /* If we have a register that acts as a program counter, mark it as | |
738 | a destination for the return address. If we have a register that | |
739 | serves as the stack pointer, arrange for it to be filled with the | |
740 | call frame address (CFA). The other registers are marked as | |
741 | unspecified. | |
742 | ||
743 | We copy the return address to the program counter, since many | |
744 | parts in GDB assume that it is possible to get the return address | |
745 | by unwinding the program counter register. However, on ISA's | |
746 | with a dedicated return address register, the CFI usually only | |
747 | contains information to unwind that return address register. | |
748 | ||
749 | The reason we're treating the stack pointer special here is | |
750 | because in many cases GCC doesn't emit CFI for the stack pointer | |
751 | and implicitly assumes that it is equal to the CFA. This makes | |
752 | some sense since the DWARF specification (version 3, draft 8, | |
753 | p. 102) says that: | |
754 | ||
755 | "Typically, the CFA is defined to be the value of the stack | |
756 | pointer at the call site in the previous frame (which may be | |
757 | different from its value on entry to the current frame)." | |
758 | ||
759 | However, this isn't true for all platforms supported by GCC | |
760 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
761 | their own architecture-specific initialization function. */ | |
05cbe71a | 762 | |
ad010def | 763 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 764 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 765 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
766 | reg->how = DWARF2_FRAME_REG_CFA; |
767 | } | |
05cbe71a | 768 | |
8f22cb90 | 769 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 770 | |
8f22cb90 | 771 | static void * |
030f20e1 | 772 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
773 | { |
774 | struct dwarf2_frame_ops *ops; | |
775 | ||
030f20e1 | 776 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
777 | ops->init_reg = dwarf2_frame_default_init_reg; |
778 | return ops; | |
779 | } | |
05cbe71a | 780 | |
8f22cb90 MK |
781 | /* Set the architecture-specific register state initialization |
782 | function for GDBARCH to INIT_REG. */ | |
783 | ||
784 | void | |
785 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
786 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
787 | struct dwarf2_frame_state_reg *, |
788 | struct frame_info *)) | |
8f22cb90 | 789 | { |
030f20e1 | 790 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 791 | |
8f22cb90 MK |
792 | ops->init_reg = init_reg; |
793 | } | |
794 | ||
795 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
796 | |
797 | static void | |
798 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 799 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 800 | struct frame_info *this_frame) |
05cbe71a | 801 | { |
030f20e1 | 802 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 803 | |
4a4e5149 | 804 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 805 | } |
3ed09a32 DJ |
806 | |
807 | /* Set the architecture-specific signal trampoline recognition | |
808 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
809 | ||
810 | void | |
811 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
812 | int (*signal_frame_p) (struct gdbarch *, | |
813 | struct frame_info *)) | |
814 | { | |
815 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
816 | ||
817 | ops->signal_frame_p = signal_frame_p; | |
818 | } | |
819 | ||
820 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 821 | THIS_FRAME. */ |
3ed09a32 DJ |
822 | |
823 | static int | |
824 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 825 | struct frame_info *this_frame) |
3ed09a32 DJ |
826 | { |
827 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
828 | ||
829 | if (ops->signal_frame_p == NULL) | |
830 | return 0; | |
4a4e5149 | 831 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 832 | } |
4bf8967c | 833 | |
4fc771b8 DJ |
834 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
835 | register numbers. */ | |
4bf8967c AS |
836 | |
837 | void | |
4fc771b8 DJ |
838 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
839 | int (*adjust_regnum) (struct gdbarch *, | |
840 | int, int)) | |
4bf8967c AS |
841 | { |
842 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
843 | ||
4fc771b8 | 844 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
845 | } |
846 | ||
4fc771b8 DJ |
847 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
848 | register. */ | |
4bf8967c | 849 | |
4fc771b8 | 850 | static int |
3e43a32a MS |
851 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, |
852 | int regnum, int eh_frame_p) | |
4bf8967c AS |
853 | { |
854 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
855 | ||
4fc771b8 | 856 | if (ops->adjust_regnum == NULL) |
4bf8967c | 857 | return regnum; |
4fc771b8 | 858 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 859 | } |
303b6f5d DJ |
860 | |
861 | static void | |
862 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
863 | struct dwarf2_fde *fde) | |
864 | { | |
303b6f5d DJ |
865 | struct symtab *s; |
866 | ||
867 | s = find_pc_symtab (fs->pc); | |
a6c727b2 | 868 | if (s == NULL) |
303b6f5d DJ |
869 | return; |
870 | ||
a6c727b2 DJ |
871 | if (producer_is_realview (s->producer)) |
872 | { | |
873 | if (fde->cie->version == 1) | |
874 | fs->armcc_cfa_offsets_sf = 1; | |
875 | ||
876 | if (fde->cie->version == 1) | |
877 | fs->armcc_cfa_offsets_reversed = 1; | |
878 | ||
879 | /* The reversed offset problem is present in some compilers | |
880 | using DWARF3, but it was eventually fixed. Check the ARM | |
881 | defined augmentations, which are in the format "armcc" followed | |
882 | by a list of one-character options. The "+" option means | |
883 | this problem is fixed (no quirk needed). If the armcc | |
884 | augmentation is missing, the quirk is needed. */ | |
885 | if (fde->cie->version == 3 | |
886 | && (strncmp (fde->cie->augmentation, "armcc", 5) != 0 | |
887 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) | |
888 | fs->armcc_cfa_offsets_reversed = 1; | |
889 | ||
890 | return; | |
891 | } | |
303b6f5d | 892 | } |
8f22cb90 MK |
893 | \f |
894 | ||
9f6f94ff TT |
895 | void |
896 | dwarf2_compile_cfa_to_ax (struct agent_expr *expr, struct axs_value *loc, | |
897 | struct gdbarch *gdbarch, | |
898 | CORE_ADDR pc, | |
899 | struct dwarf2_per_cu_data *data) | |
900 | { | |
9f6f94ff | 901 | struct dwarf2_fde *fde; |
22e048c9 | 902 | CORE_ADDR text_offset; |
9f6f94ff TT |
903 | struct dwarf2_frame_state fs; |
904 | int addr_size; | |
905 | ||
906 | memset (&fs, 0, sizeof (struct dwarf2_frame_state)); | |
907 | ||
908 | fs.pc = pc; | |
909 | ||
910 | /* Find the correct FDE. */ | |
911 | fde = dwarf2_frame_find_fde (&fs.pc, &text_offset); | |
912 | if (fde == NULL) | |
913 | error (_("Could not compute CFA; needed to translate this expression")); | |
914 | ||
915 | /* Extract any interesting information from the CIE. */ | |
916 | fs.data_align = fde->cie->data_alignment_factor; | |
917 | fs.code_align = fde->cie->code_alignment_factor; | |
918 | fs.retaddr_column = fde->cie->return_address_register; | |
919 | addr_size = fde->cie->addr_size; | |
920 | ||
921 | /* Check for "quirks" - known bugs in producers. */ | |
922 | dwarf2_frame_find_quirks (&fs, fde); | |
923 | ||
924 | /* First decode all the insns in the CIE. */ | |
925 | execute_cfa_program (fde, fde->cie->initial_instructions, | |
926 | fde->cie->end, gdbarch, pc, &fs); | |
927 | ||
928 | /* Save the initialized register set. */ | |
929 | fs.initial = fs.regs; | |
930 | fs.initial.reg = dwarf2_frame_state_copy_regs (&fs.regs); | |
931 | ||
932 | /* Then decode the insns in the FDE up to our target PC. */ | |
933 | execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, pc, &fs); | |
934 | ||
935 | /* Calculate the CFA. */ | |
936 | switch (fs.regs.cfa_how) | |
937 | { | |
938 | case CFA_REG_OFFSET: | |
939 | { | |
940 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, fs.regs.cfa_reg); | |
941 | ||
942 | if (regnum == -1) | |
943 | error (_("Unable to access DWARF register number %d"), | |
944 | (int) fs.regs.cfa_reg); /* FIXME */ | |
945 | ax_reg (expr, regnum); | |
946 | ||
947 | if (fs.regs.cfa_offset != 0) | |
948 | { | |
949 | if (fs.armcc_cfa_offsets_reversed) | |
950 | ax_const_l (expr, -fs.regs.cfa_offset); | |
951 | else | |
952 | ax_const_l (expr, fs.regs.cfa_offset); | |
953 | ax_simple (expr, aop_add); | |
954 | } | |
955 | } | |
956 | break; | |
957 | ||
958 | case CFA_EXP: | |
959 | ax_const_l (expr, text_offset); | |
960 | dwarf2_compile_expr_to_ax (expr, loc, gdbarch, addr_size, | |
961 | fs.regs.cfa_exp, | |
962 | fs.regs.cfa_exp + fs.regs.cfa_exp_len, | |
963 | data); | |
964 | break; | |
965 | ||
966 | default: | |
967 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
968 | } | |
969 | } | |
970 | ||
971 | \f | |
8f22cb90 MK |
972 | struct dwarf2_frame_cache |
973 | { | |
974 | /* DWARF Call Frame Address. */ | |
975 | CORE_ADDR cfa; | |
976 | ||
8fbca658 PA |
977 | /* Set if the return address column was marked as unavailable |
978 | (required non-collected memory or registers to compute). */ | |
979 | int unavailable_retaddr; | |
980 | ||
0228dfb9 DJ |
981 | /* Set if the return address column was marked as undefined. */ |
982 | int undefined_retaddr; | |
983 | ||
8f22cb90 MK |
984 | /* Saved registers, indexed by GDB register number, not by DWARF |
985 | register number. */ | |
986 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
987 | |
988 | /* Return address register. */ | |
989 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
990 | |
991 | /* Target address size in bytes. */ | |
992 | int addr_size; | |
ac56253d TT |
993 | |
994 | /* The .text offset. */ | |
995 | CORE_ADDR text_offset; | |
111c6489 | 996 | |
1ec56e88 PA |
997 | /* True if we already checked whether this frame is the bottom frame |
998 | of a virtual tail call frame chain. */ | |
999 | int checked_tailcall_bottom; | |
1000 | ||
111c6489 JK |
1001 | /* If not NULL then this frame is the bottom frame of a TAILCALL_FRAME |
1002 | sequence. If NULL then it is a normal case with no TAILCALL_FRAME | |
1003 | involved. Non-bottom frames of a virtual tail call frames chain use | |
1004 | dwarf2_tailcall_frame_unwind unwinder so this field does not apply for | |
1005 | them. */ | |
1006 | void *tailcall_cache; | |
1ec56e88 PA |
1007 | |
1008 | /* The number of bytes to subtract from TAILCALL_FRAME frames frame | |
1009 | base to get the SP, to simulate the return address pushed on the | |
1010 | stack. */ | |
1011 | LONGEST entry_cfa_sp_offset; | |
1012 | int entry_cfa_sp_offset_p; | |
8f22cb90 | 1013 | }; |
05cbe71a | 1014 | |
78ac5f83 TT |
1015 | /* A cleanup that sets a pointer to NULL. */ |
1016 | ||
1017 | static void | |
1018 | clear_pointer_cleanup (void *arg) | |
1019 | { | |
1020 | void **ptr = arg; | |
1021 | ||
1022 | *ptr = NULL; | |
1023 | } | |
1024 | ||
b9362cc7 | 1025 | static struct dwarf2_frame_cache * |
4a4e5149 | 1026 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a | 1027 | { |
78ac5f83 | 1028 | struct cleanup *reset_cache_cleanup, *old_chain; |
4a4e5149 | 1029 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
ad010def UW |
1030 | const int num_regs = gdbarch_num_regs (gdbarch) |
1031 | + gdbarch_num_pseudo_regs (gdbarch); | |
cfc14b3a MK |
1032 | struct dwarf2_frame_cache *cache; |
1033 | struct dwarf2_frame_state *fs; | |
1034 | struct dwarf2_fde *fde; | |
8fbca658 | 1035 | volatile struct gdb_exception ex; |
111c6489 | 1036 | CORE_ADDR entry_pc; |
111c6489 | 1037 | const gdb_byte *instr; |
cfc14b3a MK |
1038 | |
1039 | if (*this_cache) | |
1040 | return *this_cache; | |
1041 | ||
1042 | /* Allocate a new cache. */ | |
1043 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
1044 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
8fbca658 | 1045 | *this_cache = cache; |
78ac5f83 | 1046 | reset_cache_cleanup = make_cleanup (clear_pointer_cleanup, this_cache); |
cfc14b3a MK |
1047 | |
1048 | /* Allocate and initialize the frame state. */ | |
41bf6aca | 1049 | fs = XCNEW (struct dwarf2_frame_state); |
cfc14b3a MK |
1050 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); |
1051 | ||
1052 | /* Unwind the PC. | |
1053 | ||
4a4e5149 | 1054 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 1055 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 1056 | its return address. As a result the return address will |
cfc14b3a | 1057 | point at some random instruction, and the CFI for that |
e4e9607c | 1058 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
1059 | this problem by substracting 1 from the return address to get an |
1060 | address in the middle of a presumed call instruction (or the | |
1061 | instruction in the associated delay slot). This should only be | |
1062 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 1063 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 1064 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
1065 | reliable the method is though; there is the potential for the |
1066 | register state pre-call being different to that on return. */ | |
4a4e5149 | 1067 | fs->pc = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
1068 | |
1069 | /* Find the correct FDE. */ | |
ac56253d | 1070 | fde = dwarf2_frame_find_fde (&fs->pc, &cache->text_offset); |
cfc14b3a MK |
1071 | gdb_assert (fde != NULL); |
1072 | ||
1073 | /* Extract any interesting information from the CIE. */ | |
1074 | fs->data_align = fde->cie->data_alignment_factor; | |
1075 | fs->code_align = fde->cie->code_alignment_factor; | |
1076 | fs->retaddr_column = fde->cie->return_address_register; | |
ae0d2f24 | 1077 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 1078 | |
303b6f5d DJ |
1079 | /* Check for "quirks" - known bugs in producers. */ |
1080 | dwarf2_frame_find_quirks (fs, fde); | |
1081 | ||
cfc14b3a | 1082 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 1083 | execute_cfa_program (fde, fde->cie->initial_instructions, |
0c92d8c1 JB |
1084 | fde->cie->end, gdbarch, |
1085 | get_frame_address_in_block (this_frame), fs); | |
cfc14b3a MK |
1086 | |
1087 | /* Save the initialized register set. */ | |
1088 | fs->initial = fs->regs; | |
1089 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
1090 | ||
111c6489 JK |
1091 | if (get_frame_func_if_available (this_frame, &entry_pc)) |
1092 | { | |
1093 | /* Decode the insns in the FDE up to the entry PC. */ | |
1094 | instr = execute_cfa_program (fde, fde->instructions, fde->end, gdbarch, | |
1095 | entry_pc, fs); | |
1096 | ||
1097 | if (fs->regs.cfa_how == CFA_REG_OFFSET | |
1098 | && (gdbarch_dwarf2_reg_to_regnum (gdbarch, fs->regs.cfa_reg) | |
1099 | == gdbarch_sp_regnum (gdbarch))) | |
1100 | { | |
1ec56e88 PA |
1101 | cache->entry_cfa_sp_offset = fs->regs.cfa_offset; |
1102 | cache->entry_cfa_sp_offset_p = 1; | |
111c6489 JK |
1103 | } |
1104 | } | |
1105 | else | |
1106 | instr = fde->instructions; | |
1107 | ||
cfc14b3a | 1108 | /* Then decode the insns in the FDE up to our target PC. */ |
111c6489 | 1109 | execute_cfa_program (fde, instr, fde->end, gdbarch, |
0c92d8c1 | 1110 | get_frame_address_in_block (this_frame), fs); |
cfc14b3a | 1111 | |
8fbca658 | 1112 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
cfc14b3a | 1113 | { |
8fbca658 PA |
1114 | /* Calculate the CFA. */ |
1115 | switch (fs->regs.cfa_how) | |
1116 | { | |
1117 | case CFA_REG_OFFSET: | |
b1370418 | 1118 | cache->cfa = read_addr_from_reg (this_frame, fs->regs.cfa_reg); |
8fbca658 PA |
1119 | if (fs->armcc_cfa_offsets_reversed) |
1120 | cache->cfa -= fs->regs.cfa_offset; | |
1121 | else | |
1122 | cache->cfa += fs->regs.cfa_offset; | |
1123 | break; | |
1124 | ||
1125 | case CFA_EXP: | |
1126 | cache->cfa = | |
1127 | execute_stack_op (fs->regs.cfa_exp, fs->regs.cfa_exp_len, | |
1128 | cache->addr_size, cache->text_offset, | |
1129 | this_frame, 0, 0); | |
1130 | break; | |
1131 | ||
1132 | default: | |
1133 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); | |
1134 | } | |
1135 | } | |
1136 | if (ex.reason < 0) | |
1137 | { | |
1138 | if (ex.error == NOT_AVAILABLE_ERROR) | |
1139 | { | |
1140 | cache->unavailable_retaddr = 1; | |
5a1cf4d6 | 1141 | do_cleanups (old_chain); |
78ac5f83 | 1142 | discard_cleanups (reset_cache_cleanup); |
8fbca658 PA |
1143 | return cache; |
1144 | } | |
cfc14b3a | 1145 | |
8fbca658 | 1146 | throw_exception (ex); |
cfc14b3a MK |
1147 | } |
1148 | ||
05cbe71a | 1149 | /* Initialize the register state. */ |
3e2c4033 AC |
1150 | { |
1151 | int regnum; | |
e4e9607c | 1152 | |
3e2c4033 | 1153 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1154 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1155 | } |
1156 | ||
1157 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1158 | location information in the cache. Note that we don't skip the |
1159 | return address column; it's perfectly all right for it to | |
1160 | correspond to a real register. If it doesn't correspond to a | |
1161 | real register, or if we shouldn't treat it as such, | |
055d23b8 | 1162 | gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside |
f57d151a | 1163 | the range [0, gdbarch_num_regs). */ |
3e2c4033 AC |
1164 | { |
1165 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1166 | |
3e2c4033 AC |
1167 | for (column = 0; column < fs->regs.num_regs; column++) |
1168 | { | |
3e2c4033 | 1169 | /* Use the GDB register number as the destination index. */ |
ad010def | 1170 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, column); |
3e2c4033 AC |
1171 | |
1172 | /* If there's no corresponding GDB register, ignore it. */ | |
1173 | if (regnum < 0 || regnum >= num_regs) | |
1174 | continue; | |
1175 | ||
1176 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1177 | of all debug info registers. If it doesn't, complain (but |
1178 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1179 | unspecified register implies "same value" when CFI (draft |
1180 | 7) specifies nothing at all. Such a register could equally | |
1181 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1182 | isn't sufficient; it only checks that all registers in the |
1183 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1184 | problems when a debug info register falls outside of the |
e4e9607c | 1185 | table. We need a way of iterating through all the valid |
3e2c4033 | 1186 | DWARF2 register numbers. */ |
05cbe71a | 1187 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1188 | { |
1189 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 | 1190 | complaint (&symfile_complaints, _("\ |
5af949e3 | 1191 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1192 | gdbarch_register_name (gdbarch, regnum), |
5af949e3 | 1193 | paddress (gdbarch, fs->pc)); |
f059bf6f | 1194 | } |
35889917 MK |
1195 | else |
1196 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
1197 | } |
1198 | } | |
cfc14b3a | 1199 | |
8d5a9abc MK |
1200 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1201 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1202 | { |
1203 | int regnum; | |
1204 | ||
1205 | for (regnum = 0; regnum < num_regs; regnum++) | |
1206 | { | |
8d5a9abc MK |
1207 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1208 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1209 | { |
05cbe71a MK |
1210 | struct dwarf2_frame_state_reg *retaddr_reg = |
1211 | &fs->regs.reg[fs->retaddr_column]; | |
1212 | ||
d4f10bf2 MK |
1213 | /* It seems rather bizarre to specify an "empty" column as |
1214 | the return adress column. However, this is exactly | |
1215 | what GCC does on some targets. It turns out that GCC | |
1216 | assumes that the return address can be found in the | |
1217 | register corresponding to the return address column. | |
8d5a9abc MK |
1218 | Incidentally, that's how we should treat a return |
1219 | address column specifying "same value" too. */ | |
d4f10bf2 | 1220 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
1221 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
1222 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1223 | { |
1224 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
1225 | cache->reg[regnum] = *retaddr_reg; | |
1226 | else | |
1227 | cache->retaddr_reg = *retaddr_reg; | |
1228 | } | |
35889917 MK |
1229 | else |
1230 | { | |
8d5a9abc MK |
1231 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1232 | { | |
1233 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
1234 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
1235 | } | |
1236 | else | |
1237 | { | |
1238 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
1239 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
1240 | } | |
35889917 MK |
1241 | } |
1242 | } | |
1243 | } | |
1244 | } | |
cfc14b3a | 1245 | |
0228dfb9 DJ |
1246 | if (fs->retaddr_column < fs->regs.num_regs |
1247 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
1248 | cache->undefined_retaddr = 1; | |
1249 | ||
cfc14b3a | 1250 | do_cleanups (old_chain); |
78ac5f83 | 1251 | discard_cleanups (reset_cache_cleanup); |
cfc14b3a MK |
1252 | return cache; |
1253 | } | |
1254 | ||
8fbca658 PA |
1255 | static enum unwind_stop_reason |
1256 | dwarf2_frame_unwind_stop_reason (struct frame_info *this_frame, | |
1257 | void **this_cache) | |
1258 | { | |
1259 | struct dwarf2_frame_cache *cache | |
1260 | = dwarf2_frame_cache (this_frame, this_cache); | |
1261 | ||
1262 | if (cache->unavailable_retaddr) | |
1263 | return UNWIND_UNAVAILABLE; | |
1264 | ||
1265 | if (cache->undefined_retaddr) | |
1266 | return UNWIND_OUTERMOST; | |
1267 | ||
1268 | return UNWIND_NO_REASON; | |
1269 | } | |
1270 | ||
cfc14b3a | 1271 | static void |
4a4e5149 | 1272 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1273 | struct frame_id *this_id) |
1274 | { | |
1275 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1276 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1277 | |
8fbca658 | 1278 | if (cache->unavailable_retaddr) |
5ce0145d PA |
1279 | (*this_id) = frame_id_build_unavailable_stack (get_frame_func (this_frame)); |
1280 | else if (cache->undefined_retaddr) | |
8fbca658 | 1281 | return; |
5ce0145d PA |
1282 | else |
1283 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); | |
93d42b30 DJ |
1284 | } |
1285 | ||
4a4e5149 DJ |
1286 | static struct value * |
1287 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1288 | int regnum) | |
93d42b30 | 1289 | { |
4a4e5149 | 1290 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1291 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1292 | dwarf2_frame_cache (this_frame, this_cache); |
1293 | CORE_ADDR addr; | |
1294 | int realnum; | |
cfc14b3a | 1295 | |
1ec56e88 PA |
1296 | /* Check whether THIS_FRAME is the bottom frame of a virtual tail |
1297 | call frame chain. */ | |
1298 | if (!cache->checked_tailcall_bottom) | |
1299 | { | |
1300 | cache->checked_tailcall_bottom = 1; | |
1301 | dwarf2_tailcall_sniffer_first (this_frame, &cache->tailcall_cache, | |
1302 | (cache->entry_cfa_sp_offset_p | |
1303 | ? &cache->entry_cfa_sp_offset : NULL)); | |
1304 | } | |
1305 | ||
111c6489 JK |
1306 | /* Non-bottom frames of a virtual tail call frames chain use |
1307 | dwarf2_tailcall_frame_unwind unwinder so this code does not apply for | |
1308 | them. If dwarf2_tailcall_prev_register_first does not have specific value | |
1309 | unwind the register, tail call frames are assumed to have the register set | |
1310 | of the top caller. */ | |
1311 | if (cache->tailcall_cache) | |
1312 | { | |
1313 | struct value *val; | |
1314 | ||
1315 | val = dwarf2_tailcall_prev_register_first (this_frame, | |
1316 | &cache->tailcall_cache, | |
1317 | regnum); | |
1318 | if (val) | |
1319 | return val; | |
1320 | } | |
1321 | ||
cfc14b3a MK |
1322 | switch (cache->reg[regnum].how) |
1323 | { | |
05cbe71a | 1324 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1325 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1326 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1327 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1328 | |
05cbe71a | 1329 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1330 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1331 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1332 | |
05cbe71a | 1333 | case DWARF2_FRAME_REG_SAVED_REG: |
4a4e5149 DJ |
1334 | realnum |
1335 | = gdbarch_dwarf2_reg_to_regnum (gdbarch, cache->reg[regnum].loc.reg); | |
1336 | return frame_unwind_got_register (this_frame, regnum, realnum); | |
cfc14b3a | 1337 | |
05cbe71a | 1338 | case DWARF2_FRAME_REG_SAVED_EXP: |
4a4e5149 DJ |
1339 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1340 | cache->reg[regnum].exp_len, | |
ac56253d TT |
1341 | cache->addr_size, cache->text_offset, |
1342 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1343 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1344 | |
46ea248b | 1345 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1346 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1347 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1348 | |
1349 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
4a4e5149 DJ |
1350 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1351 | cache->reg[regnum].exp_len, | |
ac56253d TT |
1352 | cache->addr_size, cache->text_offset, |
1353 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1354 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1355 | |
05cbe71a | 1356 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1357 | /* GCC, in its infinite wisdom decided to not provide unwind |
1358 | information for registers that are "same value". Since | |
1359 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1360 | registers are actually undefined (which is different to CFI | |
1361 | "undefined"). Code above issues a complaint about this. | |
1362 | Here just fudge the books, assume GCC, and that the value is | |
1363 | more inner on the stack. */ | |
4a4e5149 | 1364 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1365 | |
05cbe71a | 1366 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1367 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1368 | |
05cbe71a | 1369 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1370 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1371 | |
ea7963f0 | 1372 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1373 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1374 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1375 | |
8d5a9abc | 1376 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 DJ |
1377 | addr = cache->reg[regnum].loc.offset; |
1378 | regnum = gdbarch_dwarf2_reg_to_regnum | |
1379 | (gdbarch, cache->retaddr_reg.loc.reg); | |
1380 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1381 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1382 | |
b39cc962 DJ |
1383 | case DWARF2_FRAME_REG_FN: |
1384 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1385 | ||
cfc14b3a | 1386 | default: |
e2e0b3e5 | 1387 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1388 | } |
1389 | } | |
1390 | ||
111c6489 JK |
1391 | /* Proxy for tailcall_frame_dealloc_cache for bottom frame of a virtual tail |
1392 | call frames chain. */ | |
1393 | ||
1394 | static void | |
1395 | dwarf2_frame_dealloc_cache (struct frame_info *self, void *this_cache) | |
1396 | { | |
1397 | struct dwarf2_frame_cache *cache = dwarf2_frame_cache (self, &this_cache); | |
1398 | ||
1399 | if (cache->tailcall_cache) | |
1400 | dwarf2_tailcall_frame_unwind.dealloc_cache (self, cache->tailcall_cache); | |
1401 | } | |
1402 | ||
4a4e5149 DJ |
1403 | static int |
1404 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1405 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1406 | { |
1ce5d6dd | 1407 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1408 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1409 | end up returning something past the end of this function's body. |
1410 | If the frame we're sniffing for is a signal frame whose start | |
1411 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1412 | extend one byte before its start address or we could potentially |
1413 | select the FDE of the previous function. */ | |
1414 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1415 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1416 | |
56c987f6 | 1417 | if (!fde) |
4a4e5149 | 1418 | return 0; |
3ed09a32 DJ |
1419 | |
1420 | /* On some targets, signal trampolines may have unwind information. | |
1421 | We need to recognize them so that we set the frame type | |
1422 | correctly. */ | |
1423 | ||
56c987f6 | 1424 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1425 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1426 | this_frame)) | |
1427 | return self->type == SIGTRAMP_FRAME; | |
1428 | ||
111c6489 JK |
1429 | if (self->type != NORMAL_FRAME) |
1430 | return 0; | |
1431 | ||
111c6489 | 1432 | return 1; |
4a4e5149 DJ |
1433 | } |
1434 | ||
1435 | static const struct frame_unwind dwarf2_frame_unwind = | |
1436 | { | |
1437 | NORMAL_FRAME, | |
8fbca658 | 1438 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1439 | dwarf2_frame_this_id, |
1440 | dwarf2_frame_prev_register, | |
1441 | NULL, | |
111c6489 JK |
1442 | dwarf2_frame_sniffer, |
1443 | dwarf2_frame_dealloc_cache | |
4a4e5149 DJ |
1444 | }; |
1445 | ||
1446 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1447 | { | |
1448 | SIGTRAMP_FRAME, | |
8fbca658 | 1449 | dwarf2_frame_unwind_stop_reason, |
4a4e5149 DJ |
1450 | dwarf2_frame_this_id, |
1451 | dwarf2_frame_prev_register, | |
1452 | NULL, | |
111c6489 JK |
1453 | dwarf2_frame_sniffer, |
1454 | ||
1455 | /* TAILCALL_CACHE can never be in such frame to need dealloc_cache. */ | |
1456 | NULL | |
4a4e5149 | 1457 | }; |
cfc14b3a | 1458 | |
4a4e5149 DJ |
1459 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1460 | ||
1461 | void | |
1462 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1463 | { | |
111c6489 JK |
1464 | /* TAILCALL_FRAME must be first to find the record by |
1465 | dwarf2_tailcall_sniffer_first. */ | |
1466 | frame_unwind_append_unwinder (gdbarch, &dwarf2_tailcall_frame_unwind); | |
1467 | ||
4a4e5149 DJ |
1468 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); |
1469 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1470 | } |
1471 | \f | |
1472 | ||
1473 | /* There is no explicitly defined relationship between the CFA and the | |
1474 | location of frame's local variables and arguments/parameters. | |
1475 | Therefore, frame base methods on this page should probably only be | |
1476 | used as a last resort, just to avoid printing total garbage as a | |
1477 | response to the "info frame" command. */ | |
1478 | ||
1479 | static CORE_ADDR | |
4a4e5149 | 1480 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1481 | { |
1482 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1483 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1484 | |
1485 | return cache->cfa; | |
1486 | } | |
1487 | ||
1488 | static const struct frame_base dwarf2_frame_base = | |
1489 | { | |
1490 | &dwarf2_frame_unwind, | |
1491 | dwarf2_frame_base_address, | |
1492 | dwarf2_frame_base_address, | |
1493 | dwarf2_frame_base_address | |
1494 | }; | |
1495 | ||
1496 | const struct frame_base * | |
4a4e5149 | 1497 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1498 | { |
4a4e5149 | 1499 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1500 | |
ac56253d | 1501 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1502 | return &dwarf2_frame_base; |
1503 | ||
1504 | return NULL; | |
1505 | } | |
e7802207 TT |
1506 | |
1507 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1508 | the DWARF unwinder. This is used to implement | |
1509 | DW_OP_call_frame_cfa. */ | |
1510 | ||
1511 | CORE_ADDR | |
1512 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1513 | { | |
0b722aec MM |
1514 | if (frame_unwinder_is (this_frame, &record_btrace_tailcall_frame_unwind) |
1515 | || frame_unwinder_is (this_frame, &record_btrace_frame_unwind)) | |
1516 | throw_error (NOT_AVAILABLE_ERROR, | |
1517 | _("cfa not available for record btrace target")); | |
1518 | ||
e7802207 TT |
1519 | while (get_frame_type (this_frame) == INLINE_FRAME) |
1520 | this_frame = get_prev_frame (this_frame); | |
32261e52 MM |
1521 | if (get_frame_unwind_stop_reason (this_frame) == UNWIND_UNAVAILABLE) |
1522 | throw_error (NOT_AVAILABLE_ERROR, | |
1523 | _("can't compute CFA for this frame: " | |
1524 | "required registers or memory are unavailable")); | |
e7802207 TT |
1525 | /* This restriction could be lifted if other unwinders are known to |
1526 | compute the frame base in a way compatible with the DWARF | |
1527 | unwinder. */ | |
111c6489 JK |
1528 | if (!frame_unwinder_is (this_frame, &dwarf2_frame_unwind) |
1529 | && !frame_unwinder_is (this_frame, &dwarf2_tailcall_frame_unwind)) | |
e7802207 TT |
1530 | error (_("can't compute CFA for this frame")); |
1531 | return get_frame_base (this_frame); | |
1532 | } | |
cfc14b3a | 1533 | \f |
8f22cb90 | 1534 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1535 | |
cfc14b3a | 1536 | static unsigned int |
f664829e | 1537 | read_1_byte (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1538 | { |
852483bc | 1539 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1540 | } |
1541 | ||
1542 | static unsigned int | |
f664829e | 1543 | read_4_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1544 | { |
852483bc | 1545 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1546 | } |
1547 | ||
1548 | static ULONGEST | |
f664829e | 1549 | read_8_bytes (bfd *abfd, const gdb_byte *buf) |
cfc14b3a | 1550 | { |
852483bc | 1551 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1552 | } |
1553 | ||
1554 | static ULONGEST | |
f664829e DE |
1555 | read_initial_length (bfd *abfd, const gdb_byte *buf, |
1556 | unsigned int *bytes_read_ptr) | |
cfc14b3a MK |
1557 | { |
1558 | LONGEST result; | |
1559 | ||
852483bc | 1560 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1561 | if (result == 0xffffffff) |
1562 | { | |
852483bc | 1563 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1564 | *bytes_read_ptr = 12; |
1565 | } | |
1566 | else | |
1567 | *bytes_read_ptr = 4; | |
1568 | ||
1569 | return result; | |
1570 | } | |
1571 | \f | |
1572 | ||
1573 | /* Pointer encoding helper functions. */ | |
1574 | ||
1575 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1576 | technical reasons, it encodes addresses in its FDE's in a different | |
1577 | way. Several "pointer encodings" are supported. The encoding | |
1578 | that's used for a particular FDE is determined by the 'R' | |
1579 | augmentation in the associated CIE. The argument of this | |
1580 | augmentation is a single byte. | |
1581 | ||
1582 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1583 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1584 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1585 | address should be interpreted (absolute, relative to the current | |
1586 | position in the FDE, ...). Bit 7, indicates that the address | |
1587 | should be dereferenced. */ | |
1588 | ||
852483bc | 1589 | static gdb_byte |
cfc14b3a MK |
1590 | encoding_for_size (unsigned int size) |
1591 | { | |
1592 | switch (size) | |
1593 | { | |
1594 | case 2: | |
1595 | return DW_EH_PE_udata2; | |
1596 | case 4: | |
1597 | return DW_EH_PE_udata4; | |
1598 | case 8: | |
1599 | return DW_EH_PE_udata8; | |
1600 | default: | |
e2e0b3e5 | 1601 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1602 | } |
1603 | } | |
1604 | ||
cfc14b3a | 1605 | static CORE_ADDR |
852483bc | 1606 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1607 | int ptr_len, const gdb_byte *buf, |
1608 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1609 | CORE_ADDR func_base) |
cfc14b3a | 1610 | { |
68f6cf99 | 1611 | ptrdiff_t offset; |
cfc14b3a MK |
1612 | CORE_ADDR base; |
1613 | ||
1614 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1615 | FDE's. */ | |
1616 | if (encoding & DW_EH_PE_indirect) | |
1617 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1618 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1619 | |
68f6cf99 MK |
1620 | *bytes_read_ptr = 0; |
1621 | ||
cfc14b3a MK |
1622 | switch (encoding & 0x70) |
1623 | { | |
1624 | case DW_EH_PE_absptr: | |
1625 | base = 0; | |
1626 | break; | |
1627 | case DW_EH_PE_pcrel: | |
f2fec864 | 1628 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1629 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1630 | break; |
0912c7f2 MK |
1631 | case DW_EH_PE_datarel: |
1632 | base = unit->dbase; | |
1633 | break; | |
0fd85043 CV |
1634 | case DW_EH_PE_textrel: |
1635 | base = unit->tbase; | |
1636 | break; | |
03ac2a74 | 1637 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1638 | base = func_base; |
03ac2a74 | 1639 | break; |
68f6cf99 MK |
1640 | case DW_EH_PE_aligned: |
1641 | base = 0; | |
852483bc | 1642 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1643 | if ((offset % ptr_len) != 0) |
1644 | { | |
1645 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1646 | buf += *bytes_read_ptr; | |
1647 | } | |
1648 | break; | |
cfc14b3a | 1649 | default: |
3e43a32a MS |
1650 | internal_error (__FILE__, __LINE__, |
1651 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1652 | } |
1653 | ||
b04de778 | 1654 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1655 | { |
1656 | encoding |= encoding_for_size (ptr_len); | |
1657 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1658 | encoding |= DW_EH_PE_signed; | |
1659 | } | |
cfc14b3a MK |
1660 | |
1661 | switch (encoding & 0x0f) | |
1662 | { | |
a81b10ae MK |
1663 | case DW_EH_PE_uleb128: |
1664 | { | |
9fccedf7 | 1665 | uint64_t value; |
0d45f56e | 1666 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1667 | |
f664829e | 1668 | *bytes_read_ptr += safe_read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1669 | return base + value; |
1670 | } | |
cfc14b3a | 1671 | case DW_EH_PE_udata2: |
68f6cf99 | 1672 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1673 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1674 | case DW_EH_PE_udata4: | |
68f6cf99 | 1675 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1676 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1677 | case DW_EH_PE_udata8: | |
68f6cf99 | 1678 | *bytes_read_ptr += 8; |
cfc14b3a | 1679 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1680 | case DW_EH_PE_sleb128: |
1681 | { | |
9fccedf7 | 1682 | int64_t value; |
0d45f56e | 1683 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1684 | |
f664829e | 1685 | *bytes_read_ptr += safe_read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1686 | return base + value; |
1687 | } | |
cfc14b3a | 1688 | case DW_EH_PE_sdata2: |
68f6cf99 | 1689 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1690 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1691 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1692 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1693 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1694 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1695 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1696 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1697 | default: | |
3e43a32a MS |
1698 | internal_error (__FILE__, __LINE__, |
1699 | _("Invalid or unsupported encoding")); | |
cfc14b3a MK |
1700 | } |
1701 | } | |
1702 | \f | |
1703 | ||
b01c8410 PP |
1704 | static int |
1705 | bsearch_cie_cmp (const void *key, const void *element) | |
cfc14b3a | 1706 | { |
b01c8410 PP |
1707 | ULONGEST cie_pointer = *(ULONGEST *) key; |
1708 | struct dwarf2_cie *cie = *(struct dwarf2_cie **) element; | |
cfc14b3a | 1709 | |
b01c8410 PP |
1710 | if (cie_pointer == cie->cie_pointer) |
1711 | return 0; | |
cfc14b3a | 1712 | |
b01c8410 PP |
1713 | return (cie_pointer < cie->cie_pointer) ? -1 : 1; |
1714 | } | |
1715 | ||
1716 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ | |
1717 | static struct dwarf2_cie * | |
1718 | find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer) | |
1719 | { | |
1720 | struct dwarf2_cie **p_cie; | |
cfc14b3a | 1721 | |
65a97ab3 PP |
1722 | /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to |
1723 | bsearch be non-NULL. */ | |
1724 | if (cie_table->entries == NULL) | |
1725 | { | |
1726 | gdb_assert (cie_table->num_entries == 0); | |
1727 | return NULL; | |
1728 | } | |
1729 | ||
b01c8410 PP |
1730 | p_cie = bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries, |
1731 | sizeof (cie_table->entries[0]), bsearch_cie_cmp); | |
1732 | if (p_cie != NULL) | |
1733 | return *p_cie; | |
cfc14b3a MK |
1734 | return NULL; |
1735 | } | |
1736 | ||
b01c8410 | 1737 | /* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */ |
cfc14b3a | 1738 | static void |
b01c8410 | 1739 | add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie) |
cfc14b3a | 1740 | { |
b01c8410 PP |
1741 | const int n = cie_table->num_entries; |
1742 | ||
1743 | gdb_assert (n < 1 | |
1744 | || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer); | |
1745 | ||
1746 | cie_table->entries = | |
1747 | xrealloc (cie_table->entries, (n + 1) * sizeof (cie_table->entries[0])); | |
1748 | cie_table->entries[n] = cie; | |
1749 | cie_table->num_entries = n + 1; | |
1750 | } | |
1751 | ||
1752 | static int | |
1753 | bsearch_fde_cmp (const void *key, const void *element) | |
1754 | { | |
1755 | CORE_ADDR seek_pc = *(CORE_ADDR *) key; | |
1756 | struct dwarf2_fde *fde = *(struct dwarf2_fde **) element; | |
9a619af0 | 1757 | |
b01c8410 PP |
1758 | if (seek_pc < fde->initial_location) |
1759 | return -1; | |
1760 | if (seek_pc < fde->initial_location + fde->address_range) | |
1761 | return 0; | |
1762 | return 1; | |
cfc14b3a MK |
1763 | } |
1764 | ||
1765 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1766 | inital location associated with it into *PC. */ | |
1767 | ||
1768 | static struct dwarf2_fde * | |
ac56253d | 1769 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a MK |
1770 | { |
1771 | struct objfile *objfile; | |
1772 | ||
1773 | ALL_OBJFILES (objfile) | |
1774 | { | |
b01c8410 PP |
1775 | struct dwarf2_fde_table *fde_table; |
1776 | struct dwarf2_fde **p_fde; | |
cfc14b3a | 1777 | CORE_ADDR offset; |
b01c8410 | 1778 | CORE_ADDR seek_pc; |
cfc14b3a | 1779 | |
b01c8410 PP |
1780 | fde_table = objfile_data (objfile, dwarf2_frame_objfile_data); |
1781 | if (fde_table == NULL) | |
be391dca TT |
1782 | { |
1783 | dwarf2_build_frame_info (objfile); | |
1784 | fde_table = objfile_data (objfile, dwarf2_frame_objfile_data); | |
1785 | } | |
1786 | gdb_assert (fde_table != NULL); | |
1787 | ||
1788 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1789 | continue; |
1790 | ||
1791 | gdb_assert (objfile->section_offsets); | |
1792 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1793 | ||
b01c8410 PP |
1794 | gdb_assert (fde_table->num_entries > 0); |
1795 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1796 | continue; | |
1797 | ||
1798 | seek_pc = *pc - offset; | |
1799 | p_fde = bsearch (&seek_pc, fde_table->entries, fde_table->num_entries, | |
1800 | sizeof (fde_table->entries[0]), bsearch_fde_cmp); | |
1801 | if (p_fde != NULL) | |
1802 | { | |
1803 | *pc = (*p_fde)->initial_location + offset; | |
ac56253d TT |
1804 | if (out_offset) |
1805 | *out_offset = offset; | |
b01c8410 PP |
1806 | return *p_fde; |
1807 | } | |
cfc14b3a | 1808 | } |
cfc14b3a MK |
1809 | return NULL; |
1810 | } | |
1811 | ||
b01c8410 | 1812 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1813 | static void |
b01c8410 | 1814 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1815 | { |
b01c8410 PP |
1816 | if (fde->address_range == 0) |
1817 | /* Discard useless FDEs. */ | |
1818 | return; | |
1819 | ||
1820 | fde_table->num_entries += 1; | |
1821 | fde_table->entries = | |
1822 | xrealloc (fde_table->entries, | |
1823 | fde_table->num_entries * sizeof (fde_table->entries[0])); | |
1824 | fde_table->entries[fde_table->num_entries - 1] = fde; | |
cfc14b3a MK |
1825 | } |
1826 | ||
cfc14b3a | 1827 | #define DW64_CIE_ID 0xffffffffffffffffULL |
cfc14b3a | 1828 | |
8bd90839 FM |
1829 | /* Defines the type of eh_frames that are expected to be decoded: CIE, FDE |
1830 | or any of them. */ | |
1831 | ||
1832 | enum eh_frame_type | |
1833 | { | |
1834 | EH_CIE_TYPE_ID = 1 << 0, | |
1835 | EH_FDE_TYPE_ID = 1 << 1, | |
1836 | EH_CIE_OR_FDE_TYPE_ID = EH_CIE_TYPE_ID | EH_FDE_TYPE_ID | |
1837 | }; | |
1838 | ||
f664829e DE |
1839 | static const gdb_byte *decode_frame_entry (struct comp_unit *unit, |
1840 | const gdb_byte *start, | |
1841 | int eh_frame_p, | |
1842 | struct dwarf2_cie_table *cie_table, | |
1843 | struct dwarf2_fde_table *fde_table, | |
1844 | enum eh_frame_type entry_type); | |
8bd90839 FM |
1845 | |
1846 | /* Decode the next CIE or FDE, entry_type specifies the expected type. | |
1847 | Return NULL if invalid input, otherwise the next byte to be processed. */ | |
cfc14b3a | 1848 | |
f664829e DE |
1849 | static const gdb_byte * |
1850 | decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, | |
1851 | int eh_frame_p, | |
b01c8410 | 1852 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
1853 | struct dwarf2_fde_table *fde_table, |
1854 | enum eh_frame_type entry_type) | |
cfc14b3a | 1855 | { |
5e2b427d | 1856 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
f664829e | 1857 | const gdb_byte *buf, *end; |
cfc14b3a MK |
1858 | LONGEST length; |
1859 | unsigned int bytes_read; | |
6896c0c7 RH |
1860 | int dwarf64_p; |
1861 | ULONGEST cie_id; | |
cfc14b3a | 1862 | ULONGEST cie_pointer; |
9fccedf7 DE |
1863 | int64_t sleb128; |
1864 | uint64_t uleb128; | |
cfc14b3a | 1865 | |
6896c0c7 | 1866 | buf = start; |
cfc14b3a MK |
1867 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1868 | buf += bytes_read; | |
1869 | end = buf + length; | |
1870 | ||
0963b4bd | 1871 | /* Are we still within the section? */ |
6896c0c7 RH |
1872 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) |
1873 | return NULL; | |
1874 | ||
cfc14b3a MK |
1875 | if (length == 0) |
1876 | return end; | |
1877 | ||
6896c0c7 RH |
1878 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1879 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1880 | |
6896c0c7 | 1881 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1882 | if (eh_frame_p) |
1883 | cie_id = 0; | |
1884 | else if (dwarf64_p) | |
1885 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1886 | else |
1887 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1888 | |
1889 | if (dwarf64_p) | |
1890 | { | |
1891 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1892 | buf += 8; | |
1893 | } | |
1894 | else | |
1895 | { | |
1896 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1897 | buf += 4; | |
1898 | } | |
1899 | ||
1900 | if (cie_pointer == cie_id) | |
1901 | { | |
1902 | /* This is a CIE. */ | |
1903 | struct dwarf2_cie *cie; | |
1904 | char *augmentation; | |
28ba0b33 | 1905 | unsigned int cie_version; |
cfc14b3a | 1906 | |
8bd90839 FM |
1907 | /* Check that a CIE was expected. */ |
1908 | if ((entry_type & EH_CIE_TYPE_ID) == 0) | |
1909 | error (_("Found a CIE when not expecting it.")); | |
1910 | ||
cfc14b3a MK |
1911 | /* Record the offset into the .debug_frame section of this CIE. */ |
1912 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1913 | ||
1914 | /* Check whether we've already read it. */ | |
b01c8410 | 1915 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1916 | return end; |
1917 | ||
1918 | cie = (struct dwarf2_cie *) | |
8b92e4d5 | 1919 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1920 | sizeof (struct dwarf2_cie)); |
1921 | cie->initial_instructions = NULL; | |
1922 | cie->cie_pointer = cie_pointer; | |
1923 | ||
1924 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1925 | depends on the target address size. */ |
1926 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1927 | |
56c987f6 AO |
1928 | /* We'll determine the final value later, but we need to |
1929 | initialize it conservatively. */ | |
1930 | cie->signal_frame = 0; | |
1931 | ||
cfc14b3a | 1932 | /* Check version number. */ |
28ba0b33 | 1933 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1934 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1935 | return NULL; |
303b6f5d | 1936 | cie->version = cie_version; |
cfc14b3a MK |
1937 | buf += 1; |
1938 | ||
1939 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1940 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1941 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1942 | |
303b6f5d DJ |
1943 | /* Ignore armcc augmentations. We only use them for quirks, |
1944 | and that doesn't happen until later. */ | |
1945 | if (strncmp (augmentation, "armcc", 5) == 0) | |
1946 | augmentation += strlen (augmentation); | |
1947 | ||
cfc14b3a MK |
1948 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1949 | following the augmentation string, so it must be handled | |
1950 | first. */ | |
1951 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1952 | { | |
1953 | /* Skip. */ | |
5e2b427d | 1954 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1955 | augmentation += 2; |
1956 | } | |
1957 | ||
2dc7f7b3 TT |
1958 | if (cie->version >= 4) |
1959 | { | |
1960 | /* FIXME: check that this is the same as from the CU header. */ | |
1961 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1962 | ++buf; | |
1963 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1964 | ++buf; | |
1965 | } | |
1966 | else | |
1967 | { | |
8da614df | 1968 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1969 | cie->segment_size = 0; |
1970 | } | |
8da614df CV |
1971 | /* Address values in .eh_frame sections are defined to have the |
1972 | target's pointer size. Watchout: This breaks frame info for | |
1973 | targets with pointer size < address size, unless a .debug_frame | |
0963b4bd | 1974 | section exists as well. */ |
8da614df CV |
1975 | if (eh_frame_p) |
1976 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1977 | else | |
1978 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1979 | |
f664829e DE |
1980 | buf = gdb_read_uleb128 (buf, end, &uleb128); |
1981 | if (buf == NULL) | |
1982 | return NULL; | |
1983 | cie->code_alignment_factor = uleb128; | |
cfc14b3a | 1984 | |
f664829e DE |
1985 | buf = gdb_read_sleb128 (buf, end, &sleb128); |
1986 | if (buf == NULL) | |
1987 | return NULL; | |
1988 | cie->data_alignment_factor = sleb128; | |
cfc14b3a | 1989 | |
28ba0b33 PB |
1990 | if (cie_version == 1) |
1991 | { | |
1992 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
f664829e | 1993 | ++buf; |
28ba0b33 PB |
1994 | } |
1995 | else | |
f664829e DE |
1996 | { |
1997 | buf = gdb_read_uleb128 (buf, end, &uleb128); | |
1998 | if (buf == NULL) | |
1999 | return NULL; | |
2000 | cie->return_address_register = uleb128; | |
2001 | } | |
2002 | ||
4fc771b8 | 2003 | cie->return_address_register |
5e2b427d | 2004 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
2005 | cie->return_address_register, |
2006 | eh_frame_p); | |
4bf8967c | 2007 | |
7131cb6e RH |
2008 | cie->saw_z_augmentation = (*augmentation == 'z'); |
2009 | if (cie->saw_z_augmentation) | |
cfc14b3a | 2010 | { |
9fccedf7 | 2011 | uint64_t length; |
cfc14b3a | 2012 | |
f664829e DE |
2013 | buf = gdb_read_uleb128 (buf, end, &length); |
2014 | if (buf == NULL) | |
6896c0c7 | 2015 | return NULL; |
cfc14b3a MK |
2016 | cie->initial_instructions = buf + length; |
2017 | augmentation++; | |
2018 | } | |
2019 | ||
2020 | while (*augmentation) | |
2021 | { | |
2022 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
2023 | if (*augmentation == 'L') | |
2024 | { | |
2025 | /* Skip. */ | |
2026 | buf++; | |
2027 | augmentation++; | |
2028 | } | |
2029 | ||
2030 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
2031 | else if (*augmentation == 'R') | |
2032 | { | |
2033 | cie->encoding = *buf++; | |
2034 | augmentation++; | |
2035 | } | |
2036 | ||
2037 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
2038 | else if (*augmentation == 'P') | |
2039 | { | |
1234d960 | 2040 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 2041 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 2042 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 2043 | buf, &bytes_read, 0); |
f724bf08 | 2044 | buf += bytes_read; |
cfc14b3a MK |
2045 | augmentation++; |
2046 | } | |
2047 | ||
56c987f6 AO |
2048 | /* "S" indicates a signal frame, such that the return |
2049 | address must not be decremented to locate the call frame | |
2050 | info for the previous frame; it might even be the first | |
2051 | instruction of a function, so decrementing it would take | |
2052 | us to a different function. */ | |
2053 | else if (*augmentation == 'S') | |
2054 | { | |
2055 | cie->signal_frame = 1; | |
2056 | augmentation++; | |
2057 | } | |
2058 | ||
3e9a2e52 DJ |
2059 | /* Otherwise we have an unknown augmentation. Assume that either |
2060 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
2061 | else |
2062 | { | |
3e9a2e52 DJ |
2063 | if (cie->initial_instructions) |
2064 | buf = cie->initial_instructions; | |
cfc14b3a MK |
2065 | break; |
2066 | } | |
2067 | } | |
2068 | ||
2069 | cie->initial_instructions = buf; | |
2070 | cie->end = end; | |
b01c8410 | 2071 | cie->unit = unit; |
cfc14b3a | 2072 | |
b01c8410 | 2073 | add_cie (cie_table, cie); |
cfc14b3a MK |
2074 | } |
2075 | else | |
2076 | { | |
2077 | /* This is a FDE. */ | |
2078 | struct dwarf2_fde *fde; | |
2079 | ||
8bd90839 FM |
2080 | /* Check that an FDE was expected. */ |
2081 | if ((entry_type & EH_FDE_TYPE_ID) == 0) | |
2082 | error (_("Found an FDE when not expecting it.")); | |
2083 | ||
6896c0c7 RH |
2084 | /* In an .eh_frame section, the CIE pointer is the delta between the |
2085 | address within the FDE where the CIE pointer is stored and the | |
2086 | address of the CIE. Convert it to an offset into the .eh_frame | |
2087 | section. */ | |
cfc14b3a MK |
2088 | if (eh_frame_p) |
2089 | { | |
cfc14b3a MK |
2090 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
2091 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
2092 | } | |
2093 | ||
6896c0c7 RH |
2094 | /* In either case, validate the result is still within the section. */ |
2095 | if (cie_pointer >= unit->dwarf_frame_size) | |
2096 | return NULL; | |
2097 | ||
cfc14b3a | 2098 | fde = (struct dwarf2_fde *) |
8b92e4d5 | 2099 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a | 2100 | sizeof (struct dwarf2_fde)); |
b01c8410 | 2101 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2102 | if (fde->cie == NULL) |
2103 | { | |
2104 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
8bd90839 FM |
2105 | eh_frame_p, cie_table, fde_table, |
2106 | EH_CIE_TYPE_ID); | |
b01c8410 | 2107 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
2108 | } |
2109 | ||
2110 | gdb_assert (fde->cie != NULL); | |
2111 | ||
2112 | fde->initial_location = | |
8da614df | 2113 | read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
ae0d2f24 | 2114 | buf, &bytes_read, 0); |
cfc14b3a MK |
2115 | buf += bytes_read; |
2116 | ||
2117 | fde->address_range = | |
ae0d2f24 | 2118 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 2119 | fde->cie->ptr_size, buf, &bytes_read, 0); |
cfc14b3a MK |
2120 | buf += bytes_read; |
2121 | ||
7131cb6e RH |
2122 | /* A 'z' augmentation in the CIE implies the presence of an |
2123 | augmentation field in the FDE as well. The only thing known | |
2124 | to be in here at present is the LSDA entry for EH. So we | |
2125 | can skip the whole thing. */ | |
2126 | if (fde->cie->saw_z_augmentation) | |
2127 | { | |
9fccedf7 | 2128 | uint64_t length; |
7131cb6e | 2129 | |
f664829e DE |
2130 | buf = gdb_read_uleb128 (buf, end, &length); |
2131 | if (buf == NULL) | |
2132 | return NULL; | |
2133 | buf += length; | |
6896c0c7 RH |
2134 | if (buf > end) |
2135 | return NULL; | |
7131cb6e RH |
2136 | } |
2137 | ||
cfc14b3a MK |
2138 | fde->instructions = buf; |
2139 | fde->end = end; | |
2140 | ||
4bf8967c AS |
2141 | fde->eh_frame_p = eh_frame_p; |
2142 | ||
b01c8410 | 2143 | add_fde (fde_table, fde); |
cfc14b3a MK |
2144 | } |
2145 | ||
2146 | return end; | |
2147 | } | |
6896c0c7 | 2148 | |
8bd90839 FM |
2149 | /* Read a CIE or FDE in BUF and decode it. Entry_type specifies whether we |
2150 | expect an FDE or a CIE. */ | |
2151 | ||
f664829e DE |
2152 | static const gdb_byte * |
2153 | decode_frame_entry (struct comp_unit *unit, const gdb_byte *start, | |
2154 | int eh_frame_p, | |
b01c8410 | 2155 | struct dwarf2_cie_table *cie_table, |
8bd90839 FM |
2156 | struct dwarf2_fde_table *fde_table, |
2157 | enum eh_frame_type entry_type) | |
6896c0c7 RH |
2158 | { |
2159 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
f664829e | 2160 | const gdb_byte *ret; |
6896c0c7 RH |
2161 | ptrdiff_t start_offset; |
2162 | ||
2163 | while (1) | |
2164 | { | |
b01c8410 | 2165 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
8bd90839 | 2166 | cie_table, fde_table, entry_type); |
6896c0c7 RH |
2167 | if (ret != NULL) |
2168 | break; | |
2169 | ||
2170 | /* We have corrupt input data of some form. */ | |
2171 | ||
2172 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
2173 | and mismatches wrt padding and alignment of debug sections. */ | |
2174 | /* Note that there is no requirement in the standard for any | |
2175 | alignment at all in the frame unwind sections. Testing for | |
2176 | alignment before trying to interpret data would be incorrect. | |
2177 | ||
2178 | However, GCC traditionally arranged for frame sections to be | |
2179 | sized such that the FDE length and CIE fields happen to be | |
2180 | aligned (in theory, for performance). This, unfortunately, | |
2181 | was done with .align directives, which had the side effect of | |
2182 | forcing the section to be aligned by the linker. | |
2183 | ||
2184 | This becomes a problem when you have some other producer that | |
2185 | creates frame sections that are not as strictly aligned. That | |
2186 | produces a hole in the frame info that gets filled by the | |
2187 | linker with zeros. | |
2188 | ||
2189 | The GCC behaviour is arguably a bug, but it's effectively now | |
2190 | part of the ABI, so we're now stuck with it, at least at the | |
2191 | object file level. A smart linker may decide, in the process | |
2192 | of compressing duplicate CIE information, that it can rewrite | |
2193 | the entire output section without this extra padding. */ | |
2194 | ||
2195 | start_offset = start - unit->dwarf_frame_buffer; | |
2196 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2197 | { | |
2198 | start += 4 - (start_offset & 3); | |
2199 | workaround = ALIGN4; | |
2200 | continue; | |
2201 | } | |
2202 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2203 | { | |
2204 | start += 8 - (start_offset & 7); | |
2205 | workaround = ALIGN8; | |
2206 | continue; | |
2207 | } | |
2208 | ||
2209 | /* Nothing left to try. Arrange to return as if we've consumed | |
2210 | the entire input section. Hopefully we'll get valid info from | |
2211 | the other of .debug_frame/.eh_frame. */ | |
2212 | workaround = FAIL; | |
2213 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2214 | break; | |
2215 | } | |
2216 | ||
2217 | switch (workaround) | |
2218 | { | |
2219 | case NONE: | |
2220 | break; | |
2221 | ||
2222 | case ALIGN4: | |
3e43a32a MS |
2223 | complaint (&symfile_complaints, _("\ |
2224 | Corrupt data in %s:%s; align 4 workaround apparently succeeded"), | |
6896c0c7 RH |
2225 | unit->dwarf_frame_section->owner->filename, |
2226 | unit->dwarf_frame_section->name); | |
2227 | break; | |
2228 | ||
2229 | case ALIGN8: | |
3e43a32a MS |
2230 | complaint (&symfile_complaints, _("\ |
2231 | Corrupt data in %s:%s; align 8 workaround apparently succeeded"), | |
6896c0c7 RH |
2232 | unit->dwarf_frame_section->owner->filename, |
2233 | unit->dwarf_frame_section->name); | |
2234 | break; | |
2235 | ||
2236 | default: | |
2237 | complaint (&symfile_complaints, | |
e2e0b3e5 | 2238 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
2239 | unit->dwarf_frame_section->owner->filename, |
2240 | unit->dwarf_frame_section->name); | |
2241 | break; | |
2242 | } | |
2243 | ||
2244 | return ret; | |
2245 | } | |
cfc14b3a | 2246 | \f |
b01c8410 PP |
2247 | static int |
2248 | qsort_fde_cmp (const void *a, const void *b) | |
2249 | { | |
2250 | struct dwarf2_fde *aa = *(struct dwarf2_fde **)a; | |
2251 | struct dwarf2_fde *bb = *(struct dwarf2_fde **)b; | |
e5af178f | 2252 | |
b01c8410 | 2253 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2254 | { |
2255 | if (aa->address_range != bb->address_range | |
2256 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2257 | /* Linker bug, e.g. gold/10400. | |
2258 | Work around it by keeping stable sort order. */ | |
2259 | return (a < b) ? -1 : 1; | |
2260 | else | |
2261 | /* Put eh_frame entries after debug_frame ones. */ | |
2262 | return aa->eh_frame_p - bb->eh_frame_p; | |
2263 | } | |
b01c8410 PP |
2264 | |
2265 | return (aa->initial_location < bb->initial_location) ? -1 : 1; | |
2266 | } | |
2267 | ||
cfc14b3a MK |
2268 | void |
2269 | dwarf2_build_frame_info (struct objfile *objfile) | |
2270 | { | |
ae0d2f24 | 2271 | struct comp_unit *unit; |
f664829e | 2272 | const gdb_byte *frame_ptr; |
b01c8410 PP |
2273 | struct dwarf2_cie_table cie_table; |
2274 | struct dwarf2_fde_table fde_table; | |
be391dca | 2275 | struct dwarf2_fde_table *fde_table2; |
8bd90839 | 2276 | volatile struct gdb_exception e; |
b01c8410 PP |
2277 | |
2278 | cie_table.num_entries = 0; | |
2279 | cie_table.entries = NULL; | |
2280 | ||
2281 | fde_table.num_entries = 0; | |
2282 | fde_table.entries = NULL; | |
cfc14b3a MK |
2283 | |
2284 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
ae0d2f24 UW |
2285 | unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack, |
2286 | sizeof (struct comp_unit)); | |
2287 | unit->abfd = objfile->obfd; | |
2288 | unit->objfile = objfile; | |
2289 | unit->dbase = 0; | |
2290 | unit->tbase = 0; | |
cfc14b3a | 2291 | |
d40102a1 | 2292 | if (objfile->separate_debug_objfile_backlink == NULL) |
cfc14b3a | 2293 | { |
d40102a1 JB |
2294 | /* Do not read .eh_frame from separate file as they must be also |
2295 | present in the main file. */ | |
2296 | dwarf2_get_section_info (objfile, DWARF2_EH_FRAME, | |
2297 | &unit->dwarf_frame_section, | |
2298 | &unit->dwarf_frame_buffer, | |
2299 | &unit->dwarf_frame_size); | |
2300 | if (unit->dwarf_frame_size) | |
b01c8410 | 2301 | { |
d40102a1 JB |
2302 | asection *got, *txt; |
2303 | ||
2304 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base | |
2305 | that is used for the i386/amd64 target, which currently is | |
2306 | the only target in GCC that supports/uses the | |
2307 | DW_EH_PE_datarel encoding. */ | |
2308 | got = bfd_get_section_by_name (unit->abfd, ".got"); | |
2309 | if (got) | |
2310 | unit->dbase = got->vma; | |
2311 | ||
2312 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 | |
2313 | so far. */ | |
2314 | txt = bfd_get_section_by_name (unit->abfd, ".text"); | |
2315 | if (txt) | |
2316 | unit->tbase = txt->vma; | |
2317 | ||
8bd90839 FM |
2318 | TRY_CATCH (e, RETURN_MASK_ERROR) |
2319 | { | |
2320 | frame_ptr = unit->dwarf_frame_buffer; | |
2321 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2322 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, | |
2323 | &cie_table, &fde_table, | |
2324 | EH_CIE_OR_FDE_TYPE_ID); | |
2325 | } | |
2326 | ||
2327 | if (e.reason < 0) | |
2328 | { | |
2329 | warning (_("skipping .eh_frame info of %s: %s"), | |
4262abfb | 2330 | objfile_name (objfile), e.message); |
8bd90839 FM |
2331 | |
2332 | if (fde_table.num_entries != 0) | |
2333 | { | |
2334 | xfree (fde_table.entries); | |
2335 | fde_table.entries = NULL; | |
2336 | fde_table.num_entries = 0; | |
2337 | } | |
2338 | /* The cie_table is discarded by the next if. */ | |
2339 | } | |
d40102a1 JB |
2340 | |
2341 | if (cie_table.num_entries != 0) | |
2342 | { | |
2343 | /* Reinit cie_table: debug_frame has different CIEs. */ | |
2344 | xfree (cie_table.entries); | |
2345 | cie_table.num_entries = 0; | |
2346 | cie_table.entries = NULL; | |
2347 | } | |
b01c8410 | 2348 | } |
cfc14b3a MK |
2349 | } |
2350 | ||
3017a003 | 2351 | dwarf2_get_section_info (objfile, DWARF2_DEBUG_FRAME, |
dce234bc PP |
2352 | &unit->dwarf_frame_section, |
2353 | &unit->dwarf_frame_buffer, | |
2354 | &unit->dwarf_frame_size); | |
2355 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2356 | { |
8bd90839 FM |
2357 | int num_old_fde_entries = fde_table.num_entries; |
2358 | ||
2359 | TRY_CATCH (e, RETURN_MASK_ERROR) | |
2360 | { | |
2361 | frame_ptr = unit->dwarf_frame_buffer; | |
2362 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
2363 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, | |
2364 | &cie_table, &fde_table, | |
2365 | EH_CIE_OR_FDE_TYPE_ID); | |
2366 | } | |
2367 | if (e.reason < 0) | |
2368 | { | |
2369 | warning (_("skipping .debug_frame info of %s: %s"), | |
4262abfb | 2370 | objfile_name (objfile), e.message); |
8bd90839 FM |
2371 | |
2372 | if (fde_table.num_entries != 0) | |
2373 | { | |
2374 | fde_table.num_entries = num_old_fde_entries; | |
2375 | if (num_old_fde_entries == 0) | |
2376 | { | |
2377 | xfree (fde_table.entries); | |
2378 | fde_table.entries = NULL; | |
2379 | } | |
2380 | else | |
2381 | { | |
2382 | fde_table.entries = xrealloc (fde_table.entries, | |
2383 | fde_table.num_entries * | |
2384 | sizeof (fde_table.entries[0])); | |
2385 | } | |
2386 | } | |
2387 | fde_table.num_entries = num_old_fde_entries; | |
2388 | /* The cie_table is discarded by the next if. */ | |
2389 | } | |
b01c8410 PP |
2390 | } |
2391 | ||
2392 | /* Discard the cie_table, it is no longer needed. */ | |
2393 | if (cie_table.num_entries != 0) | |
2394 | { | |
2395 | xfree (cie_table.entries); | |
2396 | cie_table.entries = NULL; /* Paranoia. */ | |
2397 | cie_table.num_entries = 0; /* Paranoia. */ | |
2398 | } | |
2399 | ||
be391dca TT |
2400 | /* Copy fde_table to obstack: it is needed at runtime. */ |
2401 | fde_table2 = (struct dwarf2_fde_table *) | |
2402 | obstack_alloc (&objfile->objfile_obstack, sizeof (*fde_table2)); | |
2403 | ||
2404 | if (fde_table.num_entries == 0) | |
2405 | { | |
2406 | fde_table2->entries = NULL; | |
2407 | fde_table2->num_entries = 0; | |
2408 | } | |
2409 | else | |
b01c8410 | 2410 | { |
875cdfbb PA |
2411 | struct dwarf2_fde *fde_prev = NULL; |
2412 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2413 | int i; | |
b01c8410 PP |
2414 | |
2415 | /* Prepare FDE table for lookups. */ | |
2416 | qsort (fde_table.entries, fde_table.num_entries, | |
2417 | sizeof (fde_table.entries[0]), qsort_fde_cmp); | |
2418 | ||
875cdfbb PA |
2419 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2420 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2421 | ranges because there's no relocation there. It's (offset, | |
2422 | length), not (start, end). On targets where address zero is | |
2423 | just another valid address this can be a problem, since the | |
2424 | FDEs appear to be non-empty in the output --- we could pick | |
2425 | out the wrong FDE. To work around this, when overlaps are | |
2426 | detected, we prefer FDEs that do not start at zero. | |
2427 | ||
2428 | Start by finding the first FDE with non-zero start. Below | |
2429 | we'll discard all FDEs that start at zero and overlap this | |
2430 | one. */ | |
2431 | for (i = 0; i < fde_table.num_entries; i++) | |
2432 | { | |
2433 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2434 | |
875cdfbb PA |
2435 | if (fde->initial_location != 0) |
2436 | { | |
2437 | first_non_zero_fde = fde; | |
2438 | break; | |
2439 | } | |
2440 | } | |
2441 | ||
2442 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2443 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2444 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2445 | fde_table2->num_entries = 0; |
875cdfbb PA |
2446 | for (i = 0; i < fde_table.num_entries; i++) |
2447 | { | |
2448 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2449 | ||
2450 | if (fde->initial_location == 0 | |
2451 | && first_non_zero_fde != NULL | |
2452 | && (first_non_zero_fde->initial_location | |
2453 | < fde->initial_location + fde->address_range)) | |
2454 | continue; | |
2455 | ||
2456 | if (fde_prev != NULL | |
2457 | && fde_prev->initial_location == fde->initial_location) | |
2458 | continue; | |
2459 | ||
2460 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2461 | sizeof (fde_table.entries[0])); | |
2462 | ++fde_table2->num_entries; | |
2463 | fde_prev = fde; | |
2464 | } | |
b01c8410 | 2465 | fde_table2->entries = obstack_finish (&objfile->objfile_obstack); |
b01c8410 PP |
2466 | |
2467 | /* Discard the original fde_table. */ | |
2468 | xfree (fde_table.entries); | |
cfc14b3a | 2469 | } |
be391dca TT |
2470 | |
2471 | set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2); | |
cfc14b3a | 2472 | } |
0d0e1a63 MK |
2473 | |
2474 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
2475 | void _initialize_dwarf2_frame (void); | |
2476 | ||
2477 | void | |
2478 | _initialize_dwarf2_frame (void) | |
2479 | { | |
030f20e1 | 2480 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2481 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 2482 | } |