Commit | Line | Data |
---|---|---|
cfc14b3a MK |
1 | /* Frame unwinder for frames with DWARF Call Frame Information. |
2 | ||
4c38e0a4 | 3 | Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010 |
0fb0cc75 | 4 | Free Software Foundation, Inc. |
cfc14b3a MK |
5 | |
6 | Contributed by Mark Kettenis. | |
7 | ||
8 | This file is part of GDB. | |
9 | ||
10 | This program is free software; you can redistribute it and/or modify | |
11 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 12 | the Free Software Foundation; either version 3 of the License, or |
cfc14b3a MK |
13 | (at your option) any later version. |
14 | ||
15 | This program is distributed in the hope that it will be useful, | |
16 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | GNU General Public License for more details. | |
19 | ||
20 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
cfc14b3a MK |
22 | |
23 | #include "defs.h" | |
24 | #include "dwarf2expr.h" | |
fa8f86ff | 25 | #include "dwarf2.h" |
cfc14b3a MK |
26 | #include "frame.h" |
27 | #include "frame-base.h" | |
28 | #include "frame-unwind.h" | |
29 | #include "gdbcore.h" | |
30 | #include "gdbtypes.h" | |
31 | #include "symtab.h" | |
32 | #include "objfiles.h" | |
33 | #include "regcache.h" | |
f2da6b3a | 34 | #include "value.h" |
cfc14b3a MK |
35 | |
36 | #include "gdb_assert.h" | |
37 | #include "gdb_string.h" | |
38 | ||
6896c0c7 | 39 | #include "complaints.h" |
cfc14b3a MK |
40 | #include "dwarf2-frame.h" |
41 | ||
ae0d2f24 UW |
42 | struct comp_unit; |
43 | ||
cfc14b3a MK |
44 | /* Call Frame Information (CFI). */ |
45 | ||
46 | /* Common Information Entry (CIE). */ | |
47 | ||
48 | struct dwarf2_cie | |
49 | { | |
ae0d2f24 UW |
50 | /* Computation Unit for this CIE. */ |
51 | struct comp_unit *unit; | |
52 | ||
cfc14b3a MK |
53 | /* Offset into the .debug_frame section where this CIE was found. |
54 | Used to identify this CIE. */ | |
55 | ULONGEST cie_pointer; | |
56 | ||
57 | /* Constant that is factored out of all advance location | |
58 | instructions. */ | |
59 | ULONGEST code_alignment_factor; | |
60 | ||
61 | /* Constants that is factored out of all offset instructions. */ | |
62 | LONGEST data_alignment_factor; | |
63 | ||
64 | /* Return address column. */ | |
65 | ULONGEST return_address_register; | |
66 | ||
67 | /* Instruction sequence to initialize a register set. */ | |
852483bc MK |
68 | gdb_byte *initial_instructions; |
69 | gdb_byte *end; | |
cfc14b3a | 70 | |
303b6f5d DJ |
71 | /* Saved augmentation, in case it's needed later. */ |
72 | char *augmentation; | |
73 | ||
cfc14b3a | 74 | /* Encoding of addresses. */ |
852483bc | 75 | gdb_byte encoding; |
cfc14b3a | 76 | |
ae0d2f24 UW |
77 | /* Target address size in bytes. */ |
78 | int addr_size; | |
79 | ||
8da614df CV |
80 | /* Target pointer size in bytes. */ |
81 | int ptr_size; | |
82 | ||
7131cb6e RH |
83 | /* True if a 'z' augmentation existed. */ |
84 | unsigned char saw_z_augmentation; | |
85 | ||
56c987f6 AO |
86 | /* True if an 'S' augmentation existed. */ |
87 | unsigned char signal_frame; | |
88 | ||
303b6f5d DJ |
89 | /* The version recorded in the CIE. */ |
90 | unsigned char version; | |
2dc7f7b3 TT |
91 | |
92 | /* The segment size. */ | |
93 | unsigned char segment_size; | |
b01c8410 | 94 | }; |
303b6f5d | 95 | |
b01c8410 PP |
96 | struct dwarf2_cie_table |
97 | { | |
98 | int num_entries; | |
99 | struct dwarf2_cie **entries; | |
cfc14b3a MK |
100 | }; |
101 | ||
102 | /* Frame Description Entry (FDE). */ | |
103 | ||
104 | struct dwarf2_fde | |
105 | { | |
106 | /* CIE for this FDE. */ | |
107 | struct dwarf2_cie *cie; | |
108 | ||
109 | /* First location associated with this FDE. */ | |
110 | CORE_ADDR initial_location; | |
111 | ||
112 | /* Number of bytes of program instructions described by this FDE. */ | |
113 | CORE_ADDR address_range; | |
114 | ||
115 | /* Instruction sequence. */ | |
852483bc MK |
116 | gdb_byte *instructions; |
117 | gdb_byte *end; | |
cfc14b3a | 118 | |
4bf8967c AS |
119 | /* True if this FDE is read from a .eh_frame instead of a .debug_frame |
120 | section. */ | |
121 | unsigned char eh_frame_p; | |
b01c8410 | 122 | }; |
4bf8967c | 123 | |
b01c8410 PP |
124 | struct dwarf2_fde_table |
125 | { | |
126 | int num_entries; | |
127 | struct dwarf2_fde **entries; | |
cfc14b3a MK |
128 | }; |
129 | ||
ae0d2f24 UW |
130 | /* A minimal decoding of DWARF2 compilation units. We only decode |
131 | what's needed to get to the call frame information. */ | |
132 | ||
133 | struct comp_unit | |
134 | { | |
135 | /* Keep the bfd convenient. */ | |
136 | bfd *abfd; | |
137 | ||
138 | struct objfile *objfile; | |
139 | ||
ae0d2f24 UW |
140 | /* Pointer to the .debug_frame section loaded into memory. */ |
141 | gdb_byte *dwarf_frame_buffer; | |
142 | ||
143 | /* Length of the loaded .debug_frame section. */ | |
c098b58b | 144 | bfd_size_type dwarf_frame_size; |
ae0d2f24 UW |
145 | |
146 | /* Pointer to the .debug_frame section. */ | |
147 | asection *dwarf_frame_section; | |
148 | ||
149 | /* Base for DW_EH_PE_datarel encodings. */ | |
150 | bfd_vma dbase; | |
151 | ||
152 | /* Base for DW_EH_PE_textrel encodings. */ | |
153 | bfd_vma tbase; | |
154 | }; | |
155 | ||
ac56253d TT |
156 | static struct dwarf2_fde *dwarf2_frame_find_fde (CORE_ADDR *pc, |
157 | CORE_ADDR *out_offset); | |
4fc771b8 DJ |
158 | |
159 | static int dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, | |
160 | int eh_frame_p); | |
ae0d2f24 UW |
161 | |
162 | static CORE_ADDR read_encoded_value (struct comp_unit *unit, gdb_byte encoding, | |
0d45f56e | 163 | int ptr_len, const gdb_byte *buf, |
ae0d2f24 UW |
164 | unsigned int *bytes_read_ptr, |
165 | CORE_ADDR func_base); | |
cfc14b3a MK |
166 | \f |
167 | ||
168 | /* Structure describing a frame state. */ | |
169 | ||
170 | struct dwarf2_frame_state | |
171 | { | |
172 | /* Each register save state can be described in terms of a CFA slot, | |
173 | another register, or a location expression. */ | |
174 | struct dwarf2_frame_state_reg_info | |
175 | { | |
05cbe71a | 176 | struct dwarf2_frame_state_reg *reg; |
cfc14b3a MK |
177 | int num_regs; |
178 | ||
2fd481e1 PP |
179 | LONGEST cfa_offset; |
180 | ULONGEST cfa_reg; | |
181 | enum { | |
182 | CFA_UNSET, | |
183 | CFA_REG_OFFSET, | |
184 | CFA_EXP | |
185 | } cfa_how; | |
0d45f56e | 186 | const gdb_byte *cfa_exp; |
2fd481e1 | 187 | |
cfc14b3a MK |
188 | /* Used to implement DW_CFA_remember_state. */ |
189 | struct dwarf2_frame_state_reg_info *prev; | |
190 | } regs; | |
191 | ||
cfc14b3a MK |
192 | /* The PC described by the current frame state. */ |
193 | CORE_ADDR pc; | |
194 | ||
195 | /* Initial register set from the CIE. | |
196 | Used to implement DW_CFA_restore. */ | |
197 | struct dwarf2_frame_state_reg_info initial; | |
198 | ||
199 | /* The information we care about from the CIE. */ | |
200 | LONGEST data_align; | |
201 | ULONGEST code_align; | |
202 | ULONGEST retaddr_column; | |
303b6f5d DJ |
203 | |
204 | /* Flags for known producer quirks. */ | |
205 | ||
206 | /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa | |
207 | and DW_CFA_def_cfa_offset takes a factored offset. */ | |
208 | int armcc_cfa_offsets_sf; | |
209 | ||
210 | /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that | |
211 | the CFA is defined as REG - OFFSET rather than REG + OFFSET. */ | |
212 | int armcc_cfa_offsets_reversed; | |
cfc14b3a MK |
213 | }; |
214 | ||
215 | /* Store the length the expression for the CFA in the `cfa_reg' field, | |
216 | which is unused in that case. */ | |
217 | #define cfa_exp_len cfa_reg | |
218 | ||
f57d151a | 219 | /* Assert that the register set RS is large enough to store gdbarch_num_regs |
cfc14b3a MK |
220 | columns. If necessary, enlarge the register set. */ |
221 | ||
222 | static void | |
223 | dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info *rs, | |
224 | int num_regs) | |
225 | { | |
226 | size_t size = sizeof (struct dwarf2_frame_state_reg); | |
227 | ||
228 | if (num_regs <= rs->num_regs) | |
229 | return; | |
230 | ||
231 | rs->reg = (struct dwarf2_frame_state_reg *) | |
232 | xrealloc (rs->reg, num_regs * size); | |
233 | ||
234 | /* Initialize newly allocated registers. */ | |
2473a4a9 | 235 | memset (rs->reg + rs->num_regs, 0, (num_regs - rs->num_regs) * size); |
cfc14b3a MK |
236 | rs->num_regs = num_regs; |
237 | } | |
238 | ||
239 | /* Copy the register columns in register set RS into newly allocated | |
240 | memory and return a pointer to this newly created copy. */ | |
241 | ||
242 | static struct dwarf2_frame_state_reg * | |
243 | dwarf2_frame_state_copy_regs (struct dwarf2_frame_state_reg_info *rs) | |
244 | { | |
d10891d4 | 245 | size_t size = rs->num_regs * sizeof (struct dwarf2_frame_state_reg); |
cfc14b3a MK |
246 | struct dwarf2_frame_state_reg *reg; |
247 | ||
248 | reg = (struct dwarf2_frame_state_reg *) xmalloc (size); | |
249 | memcpy (reg, rs->reg, size); | |
250 | ||
251 | return reg; | |
252 | } | |
253 | ||
254 | /* Release the memory allocated to register set RS. */ | |
255 | ||
256 | static void | |
257 | dwarf2_frame_state_free_regs (struct dwarf2_frame_state_reg_info *rs) | |
258 | { | |
259 | if (rs) | |
260 | { | |
261 | dwarf2_frame_state_free_regs (rs->prev); | |
262 | ||
263 | xfree (rs->reg); | |
264 | xfree (rs); | |
265 | } | |
266 | } | |
267 | ||
268 | /* Release the memory allocated to the frame state FS. */ | |
269 | ||
270 | static void | |
271 | dwarf2_frame_state_free (void *p) | |
272 | { | |
273 | struct dwarf2_frame_state *fs = p; | |
274 | ||
275 | dwarf2_frame_state_free_regs (fs->initial.prev); | |
276 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
277 | xfree (fs->initial.reg); | |
278 | xfree (fs->regs.reg); | |
279 | xfree (fs); | |
280 | } | |
281 | \f | |
282 | ||
283 | /* Helper functions for execute_stack_op. */ | |
284 | ||
285 | static CORE_ADDR | |
286 | read_reg (void *baton, int reg) | |
287 | { | |
4a4e5149 DJ |
288 | struct frame_info *this_frame = (struct frame_info *) baton; |
289 | struct gdbarch *gdbarch = get_frame_arch (this_frame); | |
cfc14b3a | 290 | int regnum; |
852483bc | 291 | gdb_byte *buf; |
cfc14b3a | 292 | |
ad010def | 293 | regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, reg); |
cfc14b3a | 294 | |
852483bc | 295 | buf = alloca (register_size (gdbarch, regnum)); |
4a4e5149 | 296 | get_frame_register (this_frame, regnum, buf); |
f2da6b3a DJ |
297 | |
298 | /* Convert the register to an integer. This returns a LONGEST | |
299 | rather than a CORE_ADDR, but unpack_pointer does the same thing | |
300 | under the covers, and this makes more sense for non-pointer | |
301 | registers. Maybe read_reg and the associated interfaces should | |
302 | deal with "struct value" instead of CORE_ADDR. */ | |
303 | return unpack_long (register_type (gdbarch, regnum), buf); | |
cfc14b3a MK |
304 | } |
305 | ||
306 | static void | |
852483bc | 307 | read_mem (void *baton, gdb_byte *buf, CORE_ADDR addr, size_t len) |
cfc14b3a MK |
308 | { |
309 | read_memory (addr, buf, len); | |
310 | } | |
311 | ||
312 | static void | |
0d45f56e | 313 | no_get_frame_base (void *baton, const gdb_byte **start, size_t *length) |
cfc14b3a MK |
314 | { |
315 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 316 | _("Support for DW_OP_fbreg is unimplemented")); |
cfc14b3a MK |
317 | } |
318 | ||
e7802207 TT |
319 | /* Helper function for execute_stack_op. */ |
320 | ||
321 | static CORE_ADDR | |
322 | no_get_frame_cfa (void *baton) | |
323 | { | |
324 | internal_error (__FILE__, __LINE__, | |
325 | _("Support for DW_OP_call_frame_cfa is unimplemented")); | |
326 | } | |
327 | ||
8cf6f0b1 TT |
328 | /* Helper function for execute_stack_op. */ |
329 | ||
330 | static CORE_ADDR | |
331 | no_get_frame_pc (void *baton) | |
332 | { | |
333 | internal_error (__FILE__, __LINE__, | |
334 | _("Support for DW_OP_GNU_implicit_pointer is unimplemented")); | |
335 | } | |
336 | ||
cfc14b3a MK |
337 | static CORE_ADDR |
338 | no_get_tls_address (void *baton, CORE_ADDR offset) | |
339 | { | |
340 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 341 | _("Support for DW_OP_GNU_push_tls_address is unimplemented")); |
cfc14b3a MK |
342 | } |
343 | ||
5c631832 JK |
344 | /* Helper function for execute_stack_op. */ |
345 | ||
346 | static void | |
347 | no_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset) | |
348 | { | |
349 | internal_error (__FILE__, __LINE__, | |
350 | _("Support for DW_OP_call* is invalid in CFI")); | |
351 | } | |
352 | ||
a6a5a945 LM |
353 | /* Execute the required actions for both the DW_CFA_restore and |
354 | DW_CFA_restore_extended instructions. */ | |
355 | static void | |
356 | dwarf2_restore_rule (struct gdbarch *gdbarch, ULONGEST reg_num, | |
357 | struct dwarf2_frame_state *fs, int eh_frame_p) | |
358 | { | |
359 | ULONGEST reg; | |
360 | ||
361 | gdb_assert (fs->initial.reg); | |
362 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg_num, eh_frame_p); | |
363 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
364 | ||
365 | /* Check if this register was explicitly initialized in the | |
366 | CIE initial instructions. If not, default the rule to | |
367 | UNSPECIFIED. */ | |
368 | if (reg < fs->initial.num_regs) | |
369 | fs->regs.reg[reg] = fs->initial.reg[reg]; | |
370 | else | |
371 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNSPECIFIED; | |
372 | ||
373 | if (fs->regs.reg[reg].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
374 | complaint (&symfile_complaints, _("\ | |
375 | incomplete CFI data; DW_CFA_restore unspecified\n\ | |
5af949e3 | 376 | register %s (#%d) at %s"), |
a6a5a945 LM |
377 | gdbarch_register_name |
378 | (gdbarch, gdbarch_dwarf2_reg_to_regnum (gdbarch, reg)), | |
379 | gdbarch_dwarf2_reg_to_regnum (gdbarch, reg), | |
5af949e3 | 380 | paddress (gdbarch, fs->pc)); |
a6a5a945 LM |
381 | } |
382 | ||
cfc14b3a | 383 | static CORE_ADDR |
0d45f56e | 384 | execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size, |
ac56253d TT |
385 | CORE_ADDR offset, struct frame_info *this_frame, |
386 | CORE_ADDR initial, int initial_in_stack_memory) | |
cfc14b3a MK |
387 | { |
388 | struct dwarf_expr_context *ctx; | |
389 | CORE_ADDR result; | |
4a227398 | 390 | struct cleanup *old_chain; |
cfc14b3a MK |
391 | |
392 | ctx = new_dwarf_expr_context (); | |
4a227398 TT |
393 | old_chain = make_cleanup_free_dwarf_expr_context (ctx); |
394 | ||
f7fd4728 | 395 | ctx->gdbarch = get_frame_arch (this_frame); |
ae0d2f24 | 396 | ctx->addr_size = addr_size; |
ac56253d | 397 | ctx->offset = offset; |
4a4e5149 | 398 | ctx->baton = this_frame; |
cfc14b3a MK |
399 | ctx->read_reg = read_reg; |
400 | ctx->read_mem = read_mem; | |
401 | ctx->get_frame_base = no_get_frame_base; | |
e7802207 | 402 | ctx->get_frame_cfa = no_get_frame_cfa; |
8cf6f0b1 | 403 | ctx->get_frame_pc = no_get_frame_pc; |
cfc14b3a | 404 | ctx->get_tls_address = no_get_tls_address; |
5c631832 | 405 | ctx->dwarf_call = no_dwarf_call; |
cfc14b3a | 406 | |
44353522 | 407 | dwarf_expr_push (ctx, initial, initial_in_stack_memory); |
cfc14b3a | 408 | dwarf_expr_eval (ctx, exp, len); |
cfc14b3a | 409 | |
f2c7657e UW |
410 | if (ctx->location == DWARF_VALUE_MEMORY) |
411 | result = dwarf_expr_fetch_address (ctx, 0); | |
412 | else if (ctx->location == DWARF_VALUE_REGISTER) | |
413 | result = read_reg (this_frame, dwarf_expr_fetch (ctx, 0)); | |
414 | else | |
cec03d70 TT |
415 | { |
416 | /* This is actually invalid DWARF, but if we ever do run across | |
417 | it somehow, we might as well support it. So, instead, report | |
418 | it as unimplemented. */ | |
419 | error (_("Not implemented: computing unwound register using explicit value operator")); | |
420 | } | |
cfc14b3a | 421 | |
4a227398 | 422 | do_cleanups (old_chain); |
cfc14b3a MK |
423 | |
424 | return result; | |
425 | } | |
426 | \f | |
427 | ||
428 | static void | |
0d45f56e TT |
429 | execute_cfa_program (struct dwarf2_fde *fde, const gdb_byte *insn_ptr, |
430 | const gdb_byte *insn_end, struct frame_info *this_frame, | |
ae0d2f24 | 431 | struct dwarf2_frame_state *fs) |
cfc14b3a | 432 | { |
ae0d2f24 | 433 | int eh_frame_p = fde->eh_frame_p; |
4a4e5149 | 434 | CORE_ADDR pc = get_frame_pc (this_frame); |
cfc14b3a | 435 | int bytes_read; |
4a4e5149 | 436 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
e17a4113 | 437 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
cfc14b3a MK |
438 | |
439 | while (insn_ptr < insn_end && fs->pc <= pc) | |
440 | { | |
852483bc | 441 | gdb_byte insn = *insn_ptr++; |
cfc14b3a MK |
442 | ULONGEST utmp, reg; |
443 | LONGEST offset; | |
444 | ||
445 | if ((insn & 0xc0) == DW_CFA_advance_loc) | |
446 | fs->pc += (insn & 0x3f) * fs->code_align; | |
447 | else if ((insn & 0xc0) == DW_CFA_offset) | |
448 | { | |
449 | reg = insn & 0x3f; | |
4fc771b8 | 450 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
451 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
452 | offset = utmp * fs->data_align; | |
453 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 454 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
455 | fs->regs.reg[reg].loc.offset = offset; |
456 | } | |
457 | else if ((insn & 0xc0) == DW_CFA_restore) | |
458 | { | |
cfc14b3a | 459 | reg = insn & 0x3f; |
a6a5a945 | 460 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
461 | } |
462 | else | |
463 | { | |
464 | switch (insn) | |
465 | { | |
466 | case DW_CFA_set_loc: | |
ae0d2f24 | 467 | fs->pc = read_encoded_value (fde->cie->unit, fde->cie->encoding, |
8da614df | 468 | fde->cie->ptr_size, insn_ptr, |
ae0d2f24 UW |
469 | &bytes_read, fde->initial_location); |
470 | /* Apply the objfile offset for relocatable objects. */ | |
471 | fs->pc += ANOFFSET (fde->cie->unit->objfile->section_offsets, | |
472 | SECT_OFF_TEXT (fde->cie->unit->objfile)); | |
cfc14b3a MK |
473 | insn_ptr += bytes_read; |
474 | break; | |
475 | ||
476 | case DW_CFA_advance_loc1: | |
e17a4113 | 477 | utmp = extract_unsigned_integer (insn_ptr, 1, byte_order); |
cfc14b3a MK |
478 | fs->pc += utmp * fs->code_align; |
479 | insn_ptr++; | |
480 | break; | |
481 | case DW_CFA_advance_loc2: | |
e17a4113 | 482 | utmp = extract_unsigned_integer (insn_ptr, 2, byte_order); |
cfc14b3a MK |
483 | fs->pc += utmp * fs->code_align; |
484 | insn_ptr += 2; | |
485 | break; | |
486 | case DW_CFA_advance_loc4: | |
e17a4113 | 487 | utmp = extract_unsigned_integer (insn_ptr, 4, byte_order); |
cfc14b3a MK |
488 | fs->pc += utmp * fs->code_align; |
489 | insn_ptr += 4; | |
490 | break; | |
491 | ||
492 | case DW_CFA_offset_extended: | |
493 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 494 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
495 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
496 | offset = utmp * fs->data_align; | |
497 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
05cbe71a | 498 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
cfc14b3a MK |
499 | fs->regs.reg[reg].loc.offset = offset; |
500 | break; | |
501 | ||
502 | case DW_CFA_restore_extended: | |
cfc14b3a | 503 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); |
a6a5a945 | 504 | dwarf2_restore_rule (gdbarch, reg, fs, eh_frame_p); |
cfc14b3a MK |
505 | break; |
506 | ||
507 | case DW_CFA_undefined: | |
508 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 509 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 510 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 511 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_UNDEFINED; |
cfc14b3a MK |
512 | break; |
513 | ||
514 | case DW_CFA_same_value: | |
515 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 516 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 517 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 518 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAME_VALUE; |
cfc14b3a MK |
519 | break; |
520 | ||
521 | case DW_CFA_register: | |
522 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 523 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a | 524 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
4fc771b8 | 525 | utmp = dwarf2_frame_adjust_regnum (gdbarch, utmp, eh_frame_p); |
cfc14b3a | 526 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 527 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; |
cfc14b3a MK |
528 | fs->regs.reg[reg].loc.reg = utmp; |
529 | break; | |
530 | ||
531 | case DW_CFA_remember_state: | |
532 | { | |
533 | struct dwarf2_frame_state_reg_info *new_rs; | |
534 | ||
535 | new_rs = XMALLOC (struct dwarf2_frame_state_reg_info); | |
536 | *new_rs = fs->regs; | |
537 | fs->regs.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
538 | fs->regs.prev = new_rs; | |
539 | } | |
540 | break; | |
541 | ||
542 | case DW_CFA_restore_state: | |
543 | { | |
544 | struct dwarf2_frame_state_reg_info *old_rs = fs->regs.prev; | |
545 | ||
50ea7769 MK |
546 | if (old_rs == NULL) |
547 | { | |
e2e0b3e5 | 548 | complaint (&symfile_complaints, _("\ |
5af949e3 UW |
549 | bad CFI data; mismatched DW_CFA_restore_state at %s"), |
550 | paddress (gdbarch, fs->pc)); | |
50ea7769 MK |
551 | } |
552 | else | |
553 | { | |
554 | xfree (fs->regs.reg); | |
555 | fs->regs = *old_rs; | |
556 | xfree (old_rs); | |
557 | } | |
cfc14b3a MK |
558 | } |
559 | break; | |
560 | ||
561 | case DW_CFA_def_cfa: | |
2fd481e1 | 562 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg); |
cfc14b3a | 563 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
564 | |
565 | if (fs->armcc_cfa_offsets_sf) | |
566 | utmp *= fs->data_align; | |
567 | ||
2fd481e1 PP |
568 | fs->regs.cfa_offset = utmp; |
569 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
570 | break; |
571 | ||
572 | case DW_CFA_def_cfa_register: | |
2fd481e1 PP |
573 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg); |
574 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, | |
575 | fs->regs.cfa_reg, | |
576 | eh_frame_p); | |
577 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
cfc14b3a MK |
578 | break; |
579 | ||
580 | case DW_CFA_def_cfa_offset: | |
852483bc | 581 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); |
303b6f5d DJ |
582 | |
583 | if (fs->armcc_cfa_offsets_sf) | |
584 | utmp *= fs->data_align; | |
585 | ||
2fd481e1 | 586 | fs->regs.cfa_offset = utmp; |
cfc14b3a MK |
587 | /* cfa_how deliberately not set. */ |
588 | break; | |
589 | ||
a8504492 MK |
590 | case DW_CFA_nop: |
591 | break; | |
592 | ||
cfc14b3a | 593 | case DW_CFA_def_cfa_expression: |
2fd481e1 PP |
594 | insn_ptr = read_uleb128 (insn_ptr, insn_end, |
595 | &fs->regs.cfa_exp_len); | |
596 | fs->regs.cfa_exp = insn_ptr; | |
597 | fs->regs.cfa_how = CFA_EXP; | |
598 | insn_ptr += fs->regs.cfa_exp_len; | |
cfc14b3a MK |
599 | break; |
600 | ||
601 | case DW_CFA_expression: | |
602 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 603 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
cfc14b3a MK |
604 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
605 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
606 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
607 | fs->regs.reg[reg].exp_len = utmp; | |
05cbe71a | 608 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_EXP; |
cfc14b3a MK |
609 | insn_ptr += utmp; |
610 | break; | |
611 | ||
a8504492 MK |
612 | case DW_CFA_offset_extended_sf: |
613 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 614 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
a8504492 | 615 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
f6da8dd8 | 616 | offset *= fs->data_align; |
a8504492 | 617 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); |
05cbe71a | 618 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; |
a8504492 MK |
619 | fs->regs.reg[reg].loc.offset = offset; |
620 | break; | |
621 | ||
46ea248b AO |
622 | case DW_CFA_val_offset: |
623 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
624 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
625 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
626 | offset = utmp * fs->data_align; | |
627 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
628 | fs->regs.reg[reg].loc.offset = offset; | |
629 | break; | |
630 | ||
631 | case DW_CFA_val_offset_sf: | |
632 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
633 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
634 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
635 | offset *= fs->data_align; | |
636 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_OFFSET; | |
637 | fs->regs.reg[reg].loc.offset = offset; | |
638 | break; | |
639 | ||
640 | case DW_CFA_val_expression: | |
641 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
642 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
643 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
644 | fs->regs.reg[reg].loc.exp = insn_ptr; | |
645 | fs->regs.reg[reg].exp_len = utmp; | |
646 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_VAL_EXP; | |
647 | insn_ptr += utmp; | |
648 | break; | |
649 | ||
a8504492 | 650 | case DW_CFA_def_cfa_sf: |
2fd481e1 PP |
651 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &fs->regs.cfa_reg); |
652 | fs->regs.cfa_reg = dwarf2_frame_adjust_regnum (gdbarch, | |
653 | fs->regs.cfa_reg, | |
654 | eh_frame_p); | |
a8504492 | 655 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); |
2fd481e1 PP |
656 | fs->regs.cfa_offset = offset * fs->data_align; |
657 | fs->regs.cfa_how = CFA_REG_OFFSET; | |
a8504492 MK |
658 | break; |
659 | ||
660 | case DW_CFA_def_cfa_offset_sf: | |
661 | insn_ptr = read_sleb128 (insn_ptr, insn_end, &offset); | |
2fd481e1 | 662 | fs->regs.cfa_offset = offset * fs->data_align; |
a8504492 | 663 | /* cfa_how deliberately not set. */ |
cfc14b3a MK |
664 | break; |
665 | ||
a77f4086 MK |
666 | case DW_CFA_GNU_window_save: |
667 | /* This is SPARC-specific code, and contains hard-coded | |
668 | constants for the register numbering scheme used by | |
669 | GCC. Rather than having a architecture-specific | |
670 | operation that's only ever used by a single | |
671 | architecture, we provide the implementation here. | |
672 | Incidentally that's what GCC does too in its | |
673 | unwinder. */ | |
674 | { | |
4a4e5149 | 675 | int size = register_size (gdbarch, 0); |
9a619af0 | 676 | |
a77f4086 MK |
677 | dwarf2_frame_state_alloc_regs (&fs->regs, 32); |
678 | for (reg = 8; reg < 16; reg++) | |
679 | { | |
680 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_REG; | |
681 | fs->regs.reg[reg].loc.reg = reg + 16; | |
682 | } | |
683 | for (reg = 16; reg < 32; reg++) | |
684 | { | |
685 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
686 | fs->regs.reg[reg].loc.offset = (reg - 16) * size; | |
687 | } | |
688 | } | |
689 | break; | |
690 | ||
cfc14b3a MK |
691 | case DW_CFA_GNU_args_size: |
692 | /* Ignored. */ | |
693 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &utmp); | |
694 | break; | |
695 | ||
58894217 JK |
696 | case DW_CFA_GNU_negative_offset_extended: |
697 | insn_ptr = read_uleb128 (insn_ptr, insn_end, ®); | |
4fc771b8 | 698 | reg = dwarf2_frame_adjust_regnum (gdbarch, reg, eh_frame_p); |
58894217 JK |
699 | insn_ptr = read_uleb128 (insn_ptr, insn_end, &offset); |
700 | offset *= fs->data_align; | |
701 | dwarf2_frame_state_alloc_regs (&fs->regs, reg + 1); | |
702 | fs->regs.reg[reg].how = DWARF2_FRAME_REG_SAVED_OFFSET; | |
703 | fs->regs.reg[reg].loc.offset = -offset; | |
704 | break; | |
705 | ||
cfc14b3a | 706 | default: |
e2e0b3e5 | 707 | internal_error (__FILE__, __LINE__, _("Unknown CFI encountered.")); |
cfc14b3a MK |
708 | } |
709 | } | |
710 | } | |
711 | ||
712 | /* Don't allow remember/restore between CIE and FDE programs. */ | |
713 | dwarf2_frame_state_free_regs (fs->regs.prev); | |
714 | fs->regs.prev = NULL; | |
715 | } | |
8f22cb90 | 716 | \f |
cfc14b3a | 717 | |
8f22cb90 | 718 | /* Architecture-specific operations. */ |
cfc14b3a | 719 | |
8f22cb90 MK |
720 | /* Per-architecture data key. */ |
721 | static struct gdbarch_data *dwarf2_frame_data; | |
722 | ||
723 | struct dwarf2_frame_ops | |
724 | { | |
725 | /* Pre-initialize the register state REG for register REGNUM. */ | |
aff37fc1 DM |
726 | void (*init_reg) (struct gdbarch *, int, struct dwarf2_frame_state_reg *, |
727 | struct frame_info *); | |
3ed09a32 | 728 | |
4a4e5149 | 729 | /* Check whether the THIS_FRAME is a signal trampoline. */ |
3ed09a32 | 730 | int (*signal_frame_p) (struct gdbarch *, struct frame_info *); |
4bf8967c | 731 | |
4fc771b8 DJ |
732 | /* Convert .eh_frame register number to DWARF register number, or |
733 | adjust .debug_frame register number. */ | |
734 | int (*adjust_regnum) (struct gdbarch *, int, int); | |
cfc14b3a MK |
735 | }; |
736 | ||
8f22cb90 MK |
737 | /* Default architecture-specific register state initialization |
738 | function. */ | |
739 | ||
740 | static void | |
741 | dwarf2_frame_default_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 742 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 743 | struct frame_info *this_frame) |
8f22cb90 MK |
744 | { |
745 | /* If we have a register that acts as a program counter, mark it as | |
746 | a destination for the return address. If we have a register that | |
747 | serves as the stack pointer, arrange for it to be filled with the | |
748 | call frame address (CFA). The other registers are marked as | |
749 | unspecified. | |
750 | ||
751 | We copy the return address to the program counter, since many | |
752 | parts in GDB assume that it is possible to get the return address | |
753 | by unwinding the program counter register. However, on ISA's | |
754 | with a dedicated return address register, the CFI usually only | |
755 | contains information to unwind that return address register. | |
756 | ||
757 | The reason we're treating the stack pointer special here is | |
758 | because in many cases GCC doesn't emit CFI for the stack pointer | |
759 | and implicitly assumes that it is equal to the CFA. This makes | |
760 | some sense since the DWARF specification (version 3, draft 8, | |
761 | p. 102) says that: | |
762 | ||
763 | "Typically, the CFA is defined to be the value of the stack | |
764 | pointer at the call site in the previous frame (which may be | |
765 | different from its value on entry to the current frame)." | |
766 | ||
767 | However, this isn't true for all platforms supported by GCC | |
768 | (e.g. IBM S/390 and zSeries). Those architectures should provide | |
769 | their own architecture-specific initialization function. */ | |
05cbe71a | 770 | |
ad010def | 771 | if (regnum == gdbarch_pc_regnum (gdbarch)) |
8f22cb90 | 772 | reg->how = DWARF2_FRAME_REG_RA; |
ad010def | 773 | else if (regnum == gdbarch_sp_regnum (gdbarch)) |
8f22cb90 MK |
774 | reg->how = DWARF2_FRAME_REG_CFA; |
775 | } | |
05cbe71a | 776 | |
8f22cb90 | 777 | /* Return a default for the architecture-specific operations. */ |
05cbe71a | 778 | |
8f22cb90 | 779 | static void * |
030f20e1 | 780 | dwarf2_frame_init (struct obstack *obstack) |
8f22cb90 MK |
781 | { |
782 | struct dwarf2_frame_ops *ops; | |
783 | ||
030f20e1 | 784 | ops = OBSTACK_ZALLOC (obstack, struct dwarf2_frame_ops); |
8f22cb90 MK |
785 | ops->init_reg = dwarf2_frame_default_init_reg; |
786 | return ops; | |
787 | } | |
05cbe71a | 788 | |
8f22cb90 MK |
789 | /* Set the architecture-specific register state initialization |
790 | function for GDBARCH to INIT_REG. */ | |
791 | ||
792 | void | |
793 | dwarf2_frame_set_init_reg (struct gdbarch *gdbarch, | |
794 | void (*init_reg) (struct gdbarch *, int, | |
aff37fc1 DM |
795 | struct dwarf2_frame_state_reg *, |
796 | struct frame_info *)) | |
8f22cb90 | 797 | { |
030f20e1 | 798 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 799 | |
8f22cb90 MK |
800 | ops->init_reg = init_reg; |
801 | } | |
802 | ||
803 | /* Pre-initialize the register state REG for register REGNUM. */ | |
05cbe71a MK |
804 | |
805 | static void | |
806 | dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum, | |
aff37fc1 | 807 | struct dwarf2_frame_state_reg *reg, |
4a4e5149 | 808 | struct frame_info *this_frame) |
05cbe71a | 809 | { |
030f20e1 | 810 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); |
8f22cb90 | 811 | |
4a4e5149 | 812 | ops->init_reg (gdbarch, regnum, reg, this_frame); |
05cbe71a | 813 | } |
3ed09a32 DJ |
814 | |
815 | /* Set the architecture-specific signal trampoline recognition | |
816 | function for GDBARCH to SIGNAL_FRAME_P. */ | |
817 | ||
818 | void | |
819 | dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch, | |
820 | int (*signal_frame_p) (struct gdbarch *, | |
821 | struct frame_info *)) | |
822 | { | |
823 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
824 | ||
825 | ops->signal_frame_p = signal_frame_p; | |
826 | } | |
827 | ||
828 | /* Query the architecture-specific signal frame recognizer for | |
4a4e5149 | 829 | THIS_FRAME. */ |
3ed09a32 DJ |
830 | |
831 | static int | |
832 | dwarf2_frame_signal_frame_p (struct gdbarch *gdbarch, | |
4a4e5149 | 833 | struct frame_info *this_frame) |
3ed09a32 DJ |
834 | { |
835 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
836 | ||
837 | if (ops->signal_frame_p == NULL) | |
838 | return 0; | |
4a4e5149 | 839 | return ops->signal_frame_p (gdbarch, this_frame); |
3ed09a32 | 840 | } |
4bf8967c | 841 | |
4fc771b8 DJ |
842 | /* Set the architecture-specific adjustment of .eh_frame and .debug_frame |
843 | register numbers. */ | |
4bf8967c AS |
844 | |
845 | void | |
4fc771b8 DJ |
846 | dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch, |
847 | int (*adjust_regnum) (struct gdbarch *, | |
848 | int, int)) | |
4bf8967c AS |
849 | { |
850 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
851 | ||
4fc771b8 | 852 | ops->adjust_regnum = adjust_regnum; |
4bf8967c AS |
853 | } |
854 | ||
4fc771b8 DJ |
855 | /* Translate a .eh_frame register to DWARF register, or adjust a .debug_frame |
856 | register. */ | |
4bf8967c | 857 | |
4fc771b8 DJ |
858 | static int |
859 | dwarf2_frame_adjust_regnum (struct gdbarch *gdbarch, int regnum, int eh_frame_p) | |
4bf8967c AS |
860 | { |
861 | struct dwarf2_frame_ops *ops = gdbarch_data (gdbarch, dwarf2_frame_data); | |
862 | ||
4fc771b8 | 863 | if (ops->adjust_regnum == NULL) |
4bf8967c | 864 | return regnum; |
4fc771b8 | 865 | return ops->adjust_regnum (gdbarch, regnum, eh_frame_p); |
4bf8967c | 866 | } |
303b6f5d DJ |
867 | |
868 | static void | |
869 | dwarf2_frame_find_quirks (struct dwarf2_frame_state *fs, | |
870 | struct dwarf2_fde *fde) | |
871 | { | |
303b6f5d DJ |
872 | struct symtab *s; |
873 | ||
874 | s = find_pc_symtab (fs->pc); | |
a6c727b2 | 875 | if (s == NULL) |
303b6f5d DJ |
876 | return; |
877 | ||
a6c727b2 DJ |
878 | if (producer_is_realview (s->producer)) |
879 | { | |
880 | if (fde->cie->version == 1) | |
881 | fs->armcc_cfa_offsets_sf = 1; | |
882 | ||
883 | if (fde->cie->version == 1) | |
884 | fs->armcc_cfa_offsets_reversed = 1; | |
885 | ||
886 | /* The reversed offset problem is present in some compilers | |
887 | using DWARF3, but it was eventually fixed. Check the ARM | |
888 | defined augmentations, which are in the format "armcc" followed | |
889 | by a list of one-character options. The "+" option means | |
890 | this problem is fixed (no quirk needed). If the armcc | |
891 | augmentation is missing, the quirk is needed. */ | |
892 | if (fde->cie->version == 3 | |
893 | && (strncmp (fde->cie->augmentation, "armcc", 5) != 0 | |
894 | || strchr (fde->cie->augmentation + 5, '+') == NULL)) | |
895 | fs->armcc_cfa_offsets_reversed = 1; | |
896 | ||
897 | return; | |
898 | } | |
303b6f5d | 899 | } |
8f22cb90 MK |
900 | \f |
901 | ||
902 | struct dwarf2_frame_cache | |
903 | { | |
904 | /* DWARF Call Frame Address. */ | |
905 | CORE_ADDR cfa; | |
906 | ||
0228dfb9 DJ |
907 | /* Set if the return address column was marked as undefined. */ |
908 | int undefined_retaddr; | |
909 | ||
8f22cb90 MK |
910 | /* Saved registers, indexed by GDB register number, not by DWARF |
911 | register number. */ | |
912 | struct dwarf2_frame_state_reg *reg; | |
8d5a9abc MK |
913 | |
914 | /* Return address register. */ | |
915 | struct dwarf2_frame_state_reg retaddr_reg; | |
ae0d2f24 UW |
916 | |
917 | /* Target address size in bytes. */ | |
918 | int addr_size; | |
ac56253d TT |
919 | |
920 | /* The .text offset. */ | |
921 | CORE_ADDR text_offset; | |
8f22cb90 | 922 | }; |
05cbe71a | 923 | |
b9362cc7 | 924 | static struct dwarf2_frame_cache * |
4a4e5149 | 925 | dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
926 | { |
927 | struct cleanup *old_chain; | |
4a4e5149 | 928 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
ad010def UW |
929 | const int num_regs = gdbarch_num_regs (gdbarch) |
930 | + gdbarch_num_pseudo_regs (gdbarch); | |
cfc14b3a MK |
931 | struct dwarf2_frame_cache *cache; |
932 | struct dwarf2_frame_state *fs; | |
933 | struct dwarf2_fde *fde; | |
cfc14b3a MK |
934 | |
935 | if (*this_cache) | |
936 | return *this_cache; | |
937 | ||
938 | /* Allocate a new cache. */ | |
939 | cache = FRAME_OBSTACK_ZALLOC (struct dwarf2_frame_cache); | |
940 | cache->reg = FRAME_OBSTACK_CALLOC (num_regs, struct dwarf2_frame_state_reg); | |
941 | ||
942 | /* Allocate and initialize the frame state. */ | |
943 | fs = XMALLOC (struct dwarf2_frame_state); | |
944 | memset (fs, 0, sizeof (struct dwarf2_frame_state)); | |
945 | old_chain = make_cleanup (dwarf2_frame_state_free, fs); | |
946 | ||
947 | /* Unwind the PC. | |
948 | ||
4a4e5149 | 949 | Note that if the next frame is never supposed to return (i.e. a call |
cfc14b3a | 950 | to abort), the compiler might optimize away the instruction at |
4a4e5149 | 951 | its return address. As a result the return address will |
cfc14b3a | 952 | point at some random instruction, and the CFI for that |
e4e9607c | 953 | instruction is probably worthless to us. GCC's unwinder solves |
cfc14b3a MK |
954 | this problem by substracting 1 from the return address to get an |
955 | address in the middle of a presumed call instruction (or the | |
956 | instruction in the associated delay slot). This should only be | |
957 | done for "normal" frames and not for resume-type frames (signal | |
e4e9607c | 958 | handlers, sentinel frames, dummy frames). The function |
ad1193e7 | 959 | get_frame_address_in_block does just this. It's not clear how |
e4e9607c MK |
960 | reliable the method is though; there is the potential for the |
961 | register state pre-call being different to that on return. */ | |
4a4e5149 | 962 | fs->pc = get_frame_address_in_block (this_frame); |
cfc14b3a MK |
963 | |
964 | /* Find the correct FDE. */ | |
ac56253d | 965 | fde = dwarf2_frame_find_fde (&fs->pc, &cache->text_offset); |
cfc14b3a MK |
966 | gdb_assert (fde != NULL); |
967 | ||
968 | /* Extract any interesting information from the CIE. */ | |
969 | fs->data_align = fde->cie->data_alignment_factor; | |
970 | fs->code_align = fde->cie->code_alignment_factor; | |
971 | fs->retaddr_column = fde->cie->return_address_register; | |
ae0d2f24 | 972 | cache->addr_size = fde->cie->addr_size; |
cfc14b3a | 973 | |
303b6f5d DJ |
974 | /* Check for "quirks" - known bugs in producers. */ |
975 | dwarf2_frame_find_quirks (fs, fde); | |
976 | ||
cfc14b3a | 977 | /* First decode all the insns in the CIE. */ |
ae0d2f24 | 978 | execute_cfa_program (fde, fde->cie->initial_instructions, |
4a4e5149 | 979 | fde->cie->end, this_frame, fs); |
cfc14b3a MK |
980 | |
981 | /* Save the initialized register set. */ | |
982 | fs->initial = fs->regs; | |
983 | fs->initial.reg = dwarf2_frame_state_copy_regs (&fs->regs); | |
984 | ||
985 | /* Then decode the insns in the FDE up to our target PC. */ | |
4a4e5149 | 986 | execute_cfa_program (fde, fde->instructions, fde->end, this_frame, fs); |
cfc14b3a | 987 | |
938f5214 | 988 | /* Calculate the CFA. */ |
2fd481e1 | 989 | switch (fs->regs.cfa_how) |
cfc14b3a MK |
990 | { |
991 | case CFA_REG_OFFSET: | |
2fd481e1 | 992 | cache->cfa = read_reg (this_frame, fs->regs.cfa_reg); |
303b6f5d | 993 | if (fs->armcc_cfa_offsets_reversed) |
2fd481e1 | 994 | cache->cfa -= fs->regs.cfa_offset; |
303b6f5d | 995 | else |
2fd481e1 | 996 | cache->cfa += fs->regs.cfa_offset; |
cfc14b3a MK |
997 | break; |
998 | ||
999 | case CFA_EXP: | |
1000 | cache->cfa = | |
2fd481e1 | 1001 | execute_stack_op (fs->regs.cfa_exp, fs->regs.cfa_exp_len, |
ac56253d TT |
1002 | cache->addr_size, cache->text_offset, |
1003 | this_frame, 0, 0); | |
cfc14b3a MK |
1004 | break; |
1005 | ||
1006 | default: | |
e2e0b3e5 | 1007 | internal_error (__FILE__, __LINE__, _("Unknown CFA rule.")); |
cfc14b3a MK |
1008 | } |
1009 | ||
05cbe71a | 1010 | /* Initialize the register state. */ |
3e2c4033 AC |
1011 | { |
1012 | int regnum; | |
e4e9607c | 1013 | |
3e2c4033 | 1014 | for (regnum = 0; regnum < num_regs; regnum++) |
4a4e5149 | 1015 | dwarf2_frame_init_reg (gdbarch, regnum, &cache->reg[regnum], this_frame); |
3e2c4033 AC |
1016 | } |
1017 | ||
1018 | /* Go through the DWARF2 CFI generated table and save its register | |
79c4cb80 MK |
1019 | location information in the cache. Note that we don't skip the |
1020 | return address column; it's perfectly all right for it to | |
1021 | correspond to a real register. If it doesn't correspond to a | |
1022 | real register, or if we shouldn't treat it as such, | |
055d23b8 | 1023 | gdbarch_dwarf2_reg_to_regnum should be defined to return a number outside |
f57d151a | 1024 | the range [0, gdbarch_num_regs). */ |
3e2c4033 AC |
1025 | { |
1026 | int column; /* CFI speak for "register number". */ | |
e4e9607c | 1027 | |
3e2c4033 AC |
1028 | for (column = 0; column < fs->regs.num_regs; column++) |
1029 | { | |
3e2c4033 | 1030 | /* Use the GDB register number as the destination index. */ |
ad010def | 1031 | int regnum = gdbarch_dwarf2_reg_to_regnum (gdbarch, column); |
3e2c4033 AC |
1032 | |
1033 | /* If there's no corresponding GDB register, ignore it. */ | |
1034 | if (regnum < 0 || regnum >= num_regs) | |
1035 | continue; | |
1036 | ||
1037 | /* NOTE: cagney/2003-09-05: CFI should specify the disposition | |
e4e9607c MK |
1038 | of all debug info registers. If it doesn't, complain (but |
1039 | not too loudly). It turns out that GCC assumes that an | |
3e2c4033 AC |
1040 | unspecified register implies "same value" when CFI (draft |
1041 | 7) specifies nothing at all. Such a register could equally | |
1042 | be interpreted as "undefined". Also note that this check | |
e4e9607c MK |
1043 | isn't sufficient; it only checks that all registers in the |
1044 | range [0 .. max column] are specified, and won't detect | |
3e2c4033 | 1045 | problems when a debug info register falls outside of the |
e4e9607c | 1046 | table. We need a way of iterating through all the valid |
3e2c4033 | 1047 | DWARF2 register numbers. */ |
05cbe71a | 1048 | if (fs->regs.reg[column].how == DWARF2_FRAME_REG_UNSPECIFIED) |
f059bf6f AC |
1049 | { |
1050 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_UNSPECIFIED) | |
e2e0b3e5 | 1051 | complaint (&symfile_complaints, _("\ |
5af949e3 | 1052 | incomplete CFI data; unspecified registers (e.g., %s) at %s"), |
f059bf6f | 1053 | gdbarch_register_name (gdbarch, regnum), |
5af949e3 | 1054 | paddress (gdbarch, fs->pc)); |
f059bf6f | 1055 | } |
35889917 MK |
1056 | else |
1057 | cache->reg[regnum] = fs->regs.reg[column]; | |
3e2c4033 AC |
1058 | } |
1059 | } | |
cfc14b3a | 1060 | |
8d5a9abc MK |
1061 | /* Eliminate any DWARF2_FRAME_REG_RA rules, and save the information |
1062 | we need for evaluating DWARF2_FRAME_REG_RA_OFFSET rules. */ | |
35889917 MK |
1063 | { |
1064 | int regnum; | |
1065 | ||
1066 | for (regnum = 0; regnum < num_regs; regnum++) | |
1067 | { | |
8d5a9abc MK |
1068 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA |
1069 | || cache->reg[regnum].how == DWARF2_FRAME_REG_RA_OFFSET) | |
35889917 | 1070 | { |
05cbe71a MK |
1071 | struct dwarf2_frame_state_reg *retaddr_reg = |
1072 | &fs->regs.reg[fs->retaddr_column]; | |
1073 | ||
d4f10bf2 MK |
1074 | /* It seems rather bizarre to specify an "empty" column as |
1075 | the return adress column. However, this is exactly | |
1076 | what GCC does on some targets. It turns out that GCC | |
1077 | assumes that the return address can be found in the | |
1078 | register corresponding to the return address column. | |
8d5a9abc MK |
1079 | Incidentally, that's how we should treat a return |
1080 | address column specifying "same value" too. */ | |
d4f10bf2 | 1081 | if (fs->retaddr_column < fs->regs.num_regs |
05cbe71a MK |
1082 | && retaddr_reg->how != DWARF2_FRAME_REG_UNSPECIFIED |
1083 | && retaddr_reg->how != DWARF2_FRAME_REG_SAME_VALUE) | |
8d5a9abc MK |
1084 | { |
1085 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) | |
1086 | cache->reg[regnum] = *retaddr_reg; | |
1087 | else | |
1088 | cache->retaddr_reg = *retaddr_reg; | |
1089 | } | |
35889917 MK |
1090 | else |
1091 | { | |
8d5a9abc MK |
1092 | if (cache->reg[regnum].how == DWARF2_FRAME_REG_RA) |
1093 | { | |
1094 | cache->reg[regnum].loc.reg = fs->retaddr_column; | |
1095 | cache->reg[regnum].how = DWARF2_FRAME_REG_SAVED_REG; | |
1096 | } | |
1097 | else | |
1098 | { | |
1099 | cache->retaddr_reg.loc.reg = fs->retaddr_column; | |
1100 | cache->retaddr_reg.how = DWARF2_FRAME_REG_SAVED_REG; | |
1101 | } | |
35889917 MK |
1102 | } |
1103 | } | |
1104 | } | |
1105 | } | |
cfc14b3a | 1106 | |
0228dfb9 DJ |
1107 | if (fs->retaddr_column < fs->regs.num_regs |
1108 | && fs->regs.reg[fs->retaddr_column].how == DWARF2_FRAME_REG_UNDEFINED) | |
1109 | cache->undefined_retaddr = 1; | |
1110 | ||
cfc14b3a MK |
1111 | do_cleanups (old_chain); |
1112 | ||
1113 | *this_cache = cache; | |
1114 | return cache; | |
1115 | } | |
1116 | ||
1117 | static void | |
4a4e5149 | 1118 | dwarf2_frame_this_id (struct frame_info *this_frame, void **this_cache, |
cfc14b3a MK |
1119 | struct frame_id *this_id) |
1120 | { | |
1121 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1122 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a | 1123 | |
0228dfb9 DJ |
1124 | if (cache->undefined_retaddr) |
1125 | return; | |
1126 | ||
4a4e5149 | 1127 | (*this_id) = frame_id_build (cache->cfa, get_frame_func (this_frame)); |
93d42b30 DJ |
1128 | } |
1129 | ||
4a4e5149 DJ |
1130 | static struct value * |
1131 | dwarf2_frame_prev_register (struct frame_info *this_frame, void **this_cache, | |
1132 | int regnum) | |
93d42b30 | 1133 | { |
4a4e5149 | 1134 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
93d42b30 | 1135 | struct dwarf2_frame_cache *cache = |
4a4e5149 DJ |
1136 | dwarf2_frame_cache (this_frame, this_cache); |
1137 | CORE_ADDR addr; | |
1138 | int realnum; | |
cfc14b3a MK |
1139 | |
1140 | switch (cache->reg[regnum].how) | |
1141 | { | |
05cbe71a | 1142 | case DWARF2_FRAME_REG_UNDEFINED: |
3e2c4033 | 1143 | /* If CFI explicitly specified that the value isn't defined, |
e4e9607c | 1144 | mark it as optimized away; the value isn't available. */ |
4a4e5149 | 1145 | return frame_unwind_got_optimized (this_frame, regnum); |
cfc14b3a | 1146 | |
05cbe71a | 1147 | case DWARF2_FRAME_REG_SAVED_OFFSET: |
4a4e5149 DJ |
1148 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1149 | return frame_unwind_got_memory (this_frame, regnum, addr); | |
cfc14b3a | 1150 | |
05cbe71a | 1151 | case DWARF2_FRAME_REG_SAVED_REG: |
4a4e5149 DJ |
1152 | realnum |
1153 | = gdbarch_dwarf2_reg_to_regnum (gdbarch, cache->reg[regnum].loc.reg); | |
1154 | return frame_unwind_got_register (this_frame, regnum, realnum); | |
cfc14b3a | 1155 | |
05cbe71a | 1156 | case DWARF2_FRAME_REG_SAVED_EXP: |
4a4e5149 DJ |
1157 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1158 | cache->reg[regnum].exp_len, | |
ac56253d TT |
1159 | cache->addr_size, cache->text_offset, |
1160 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1161 | return frame_unwind_got_memory (this_frame, regnum, addr); |
cfc14b3a | 1162 | |
46ea248b | 1163 | case DWARF2_FRAME_REG_SAVED_VAL_OFFSET: |
4a4e5149 DJ |
1164 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1165 | return frame_unwind_got_constant (this_frame, regnum, addr); | |
46ea248b AO |
1166 | |
1167 | case DWARF2_FRAME_REG_SAVED_VAL_EXP: | |
4a4e5149 DJ |
1168 | addr = execute_stack_op (cache->reg[regnum].loc.exp, |
1169 | cache->reg[regnum].exp_len, | |
ac56253d TT |
1170 | cache->addr_size, cache->text_offset, |
1171 | this_frame, cache->cfa, 1); | |
4a4e5149 | 1172 | return frame_unwind_got_constant (this_frame, regnum, addr); |
46ea248b | 1173 | |
05cbe71a | 1174 | case DWARF2_FRAME_REG_UNSPECIFIED: |
3e2c4033 AC |
1175 | /* GCC, in its infinite wisdom decided to not provide unwind |
1176 | information for registers that are "same value". Since | |
1177 | DWARF2 (3 draft 7) doesn't define such behavior, said | |
1178 | registers are actually undefined (which is different to CFI | |
1179 | "undefined"). Code above issues a complaint about this. | |
1180 | Here just fudge the books, assume GCC, and that the value is | |
1181 | more inner on the stack. */ | |
4a4e5149 | 1182 | return frame_unwind_got_register (this_frame, regnum, regnum); |
3e2c4033 | 1183 | |
05cbe71a | 1184 | case DWARF2_FRAME_REG_SAME_VALUE: |
4a4e5149 | 1185 | return frame_unwind_got_register (this_frame, regnum, regnum); |
cfc14b3a | 1186 | |
05cbe71a | 1187 | case DWARF2_FRAME_REG_CFA: |
4a4e5149 | 1188 | return frame_unwind_got_address (this_frame, regnum, cache->cfa); |
35889917 | 1189 | |
ea7963f0 | 1190 | case DWARF2_FRAME_REG_CFA_OFFSET: |
4a4e5149 DJ |
1191 | addr = cache->cfa + cache->reg[regnum].loc.offset; |
1192 | return frame_unwind_got_address (this_frame, regnum, addr); | |
ea7963f0 | 1193 | |
8d5a9abc | 1194 | case DWARF2_FRAME_REG_RA_OFFSET: |
4a4e5149 DJ |
1195 | addr = cache->reg[regnum].loc.offset; |
1196 | regnum = gdbarch_dwarf2_reg_to_regnum | |
1197 | (gdbarch, cache->retaddr_reg.loc.reg); | |
1198 | addr += get_frame_register_unsigned (this_frame, regnum); | |
1199 | return frame_unwind_got_address (this_frame, regnum, addr); | |
8d5a9abc | 1200 | |
b39cc962 DJ |
1201 | case DWARF2_FRAME_REG_FN: |
1202 | return cache->reg[regnum].loc.fn (this_frame, this_cache, regnum); | |
1203 | ||
cfc14b3a | 1204 | default: |
e2e0b3e5 | 1205 | internal_error (__FILE__, __LINE__, _("Unknown register rule.")); |
cfc14b3a MK |
1206 | } |
1207 | } | |
1208 | ||
4a4e5149 DJ |
1209 | static int |
1210 | dwarf2_frame_sniffer (const struct frame_unwind *self, | |
1211 | struct frame_info *this_frame, void **this_cache) | |
cfc14b3a | 1212 | { |
1ce5d6dd | 1213 | /* Grab an address that is guarenteed to reside somewhere within the |
4a4e5149 | 1214 | function. get_frame_pc(), with a no-return next function, can |
93d42b30 DJ |
1215 | end up returning something past the end of this function's body. |
1216 | If the frame we're sniffing for is a signal frame whose start | |
1217 | address is placed on the stack by the OS, its FDE must | |
4a4e5149 DJ |
1218 | extend one byte before its start address or we could potentially |
1219 | select the FDE of the previous function. */ | |
1220 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); | |
ac56253d | 1221 | struct dwarf2_fde *fde = dwarf2_frame_find_fde (&block_addr, NULL); |
9a619af0 | 1222 | |
56c987f6 | 1223 | if (!fde) |
4a4e5149 | 1224 | return 0; |
3ed09a32 DJ |
1225 | |
1226 | /* On some targets, signal trampolines may have unwind information. | |
1227 | We need to recognize them so that we set the frame type | |
1228 | correctly. */ | |
1229 | ||
56c987f6 | 1230 | if (fde->cie->signal_frame |
4a4e5149 DJ |
1231 | || dwarf2_frame_signal_frame_p (get_frame_arch (this_frame), |
1232 | this_frame)) | |
1233 | return self->type == SIGTRAMP_FRAME; | |
1234 | ||
1235 | return self->type != SIGTRAMP_FRAME; | |
1236 | } | |
1237 | ||
1238 | static const struct frame_unwind dwarf2_frame_unwind = | |
1239 | { | |
1240 | NORMAL_FRAME, | |
1241 | dwarf2_frame_this_id, | |
1242 | dwarf2_frame_prev_register, | |
1243 | NULL, | |
1244 | dwarf2_frame_sniffer | |
1245 | }; | |
1246 | ||
1247 | static const struct frame_unwind dwarf2_signal_frame_unwind = | |
1248 | { | |
1249 | SIGTRAMP_FRAME, | |
1250 | dwarf2_frame_this_id, | |
1251 | dwarf2_frame_prev_register, | |
1252 | NULL, | |
1253 | dwarf2_frame_sniffer | |
1254 | }; | |
cfc14b3a | 1255 | |
4a4e5149 DJ |
1256 | /* Append the DWARF-2 frame unwinders to GDBARCH's list. */ |
1257 | ||
1258 | void | |
1259 | dwarf2_append_unwinders (struct gdbarch *gdbarch) | |
1260 | { | |
1261 | frame_unwind_append_unwinder (gdbarch, &dwarf2_frame_unwind); | |
1262 | frame_unwind_append_unwinder (gdbarch, &dwarf2_signal_frame_unwind); | |
cfc14b3a MK |
1263 | } |
1264 | \f | |
1265 | ||
1266 | /* There is no explicitly defined relationship between the CFA and the | |
1267 | location of frame's local variables and arguments/parameters. | |
1268 | Therefore, frame base methods on this page should probably only be | |
1269 | used as a last resort, just to avoid printing total garbage as a | |
1270 | response to the "info frame" command. */ | |
1271 | ||
1272 | static CORE_ADDR | |
4a4e5149 | 1273 | dwarf2_frame_base_address (struct frame_info *this_frame, void **this_cache) |
cfc14b3a MK |
1274 | { |
1275 | struct dwarf2_frame_cache *cache = | |
4a4e5149 | 1276 | dwarf2_frame_cache (this_frame, this_cache); |
cfc14b3a MK |
1277 | |
1278 | return cache->cfa; | |
1279 | } | |
1280 | ||
1281 | static const struct frame_base dwarf2_frame_base = | |
1282 | { | |
1283 | &dwarf2_frame_unwind, | |
1284 | dwarf2_frame_base_address, | |
1285 | dwarf2_frame_base_address, | |
1286 | dwarf2_frame_base_address | |
1287 | }; | |
1288 | ||
1289 | const struct frame_base * | |
4a4e5149 | 1290 | dwarf2_frame_base_sniffer (struct frame_info *this_frame) |
cfc14b3a | 1291 | { |
4a4e5149 | 1292 | CORE_ADDR block_addr = get_frame_address_in_block (this_frame); |
9a619af0 | 1293 | |
ac56253d | 1294 | if (dwarf2_frame_find_fde (&block_addr, NULL)) |
cfc14b3a MK |
1295 | return &dwarf2_frame_base; |
1296 | ||
1297 | return NULL; | |
1298 | } | |
e7802207 TT |
1299 | |
1300 | /* Compute the CFA for THIS_FRAME, but only if THIS_FRAME came from | |
1301 | the DWARF unwinder. This is used to implement | |
1302 | DW_OP_call_frame_cfa. */ | |
1303 | ||
1304 | CORE_ADDR | |
1305 | dwarf2_frame_cfa (struct frame_info *this_frame) | |
1306 | { | |
1307 | while (get_frame_type (this_frame) == INLINE_FRAME) | |
1308 | this_frame = get_prev_frame (this_frame); | |
1309 | /* This restriction could be lifted if other unwinders are known to | |
1310 | compute the frame base in a way compatible with the DWARF | |
1311 | unwinder. */ | |
1312 | if (! frame_unwinder_is (this_frame, &dwarf2_frame_unwind)) | |
1313 | error (_("can't compute CFA for this frame")); | |
1314 | return get_frame_base (this_frame); | |
1315 | } | |
cfc14b3a | 1316 | \f |
8f22cb90 | 1317 | const struct objfile_data *dwarf2_frame_objfile_data; |
0d0e1a63 | 1318 | |
cfc14b3a | 1319 | static unsigned int |
852483bc | 1320 | read_1_byte (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1321 | { |
852483bc | 1322 | return bfd_get_8 (abfd, buf); |
cfc14b3a MK |
1323 | } |
1324 | ||
1325 | static unsigned int | |
852483bc | 1326 | read_4_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1327 | { |
852483bc | 1328 | return bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1329 | } |
1330 | ||
1331 | static ULONGEST | |
852483bc | 1332 | read_8_bytes (bfd *abfd, gdb_byte *buf) |
cfc14b3a | 1333 | { |
852483bc | 1334 | return bfd_get_64 (abfd, buf); |
cfc14b3a MK |
1335 | } |
1336 | ||
1337 | static ULONGEST | |
852483bc | 1338 | read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1339 | { |
1340 | ULONGEST result; | |
1341 | unsigned int num_read; | |
1342 | int shift; | |
852483bc | 1343 | gdb_byte byte; |
cfc14b3a MK |
1344 | |
1345 | result = 0; | |
1346 | shift = 0; | |
1347 | num_read = 0; | |
1348 | ||
1349 | do | |
1350 | { | |
1351 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1352 | buf++; | |
1353 | num_read++; | |
1354 | result |= ((byte & 0x7f) << shift); | |
1355 | shift += 7; | |
1356 | } | |
1357 | while (byte & 0x80); | |
1358 | ||
1359 | *bytes_read_ptr = num_read; | |
1360 | ||
1361 | return result; | |
1362 | } | |
1363 | ||
1364 | static LONGEST | |
852483bc | 1365 | read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1366 | { |
1367 | LONGEST result; | |
1368 | int shift; | |
1369 | unsigned int num_read; | |
852483bc | 1370 | gdb_byte byte; |
cfc14b3a MK |
1371 | |
1372 | result = 0; | |
1373 | shift = 0; | |
1374 | num_read = 0; | |
1375 | ||
1376 | do | |
1377 | { | |
1378 | byte = bfd_get_8 (abfd, (bfd_byte *) buf); | |
1379 | buf++; | |
1380 | num_read++; | |
1381 | result |= ((byte & 0x7f) << shift); | |
1382 | shift += 7; | |
1383 | } | |
1384 | while (byte & 0x80); | |
1385 | ||
77e0b926 DJ |
1386 | if (shift < 8 * sizeof (result) && (byte & 0x40)) |
1387 | result |= -(((LONGEST)1) << shift); | |
cfc14b3a MK |
1388 | |
1389 | *bytes_read_ptr = num_read; | |
1390 | ||
1391 | return result; | |
1392 | } | |
1393 | ||
1394 | static ULONGEST | |
852483bc | 1395 | read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr) |
cfc14b3a MK |
1396 | { |
1397 | LONGEST result; | |
1398 | ||
852483bc | 1399 | result = bfd_get_32 (abfd, buf); |
cfc14b3a MK |
1400 | if (result == 0xffffffff) |
1401 | { | |
852483bc | 1402 | result = bfd_get_64 (abfd, buf + 4); |
cfc14b3a MK |
1403 | *bytes_read_ptr = 12; |
1404 | } | |
1405 | else | |
1406 | *bytes_read_ptr = 4; | |
1407 | ||
1408 | return result; | |
1409 | } | |
1410 | \f | |
1411 | ||
1412 | /* Pointer encoding helper functions. */ | |
1413 | ||
1414 | /* GCC supports exception handling based on DWARF2 CFI. However, for | |
1415 | technical reasons, it encodes addresses in its FDE's in a different | |
1416 | way. Several "pointer encodings" are supported. The encoding | |
1417 | that's used for a particular FDE is determined by the 'R' | |
1418 | augmentation in the associated CIE. The argument of this | |
1419 | augmentation is a single byte. | |
1420 | ||
1421 | The address can be encoded as 2 bytes, 4 bytes, 8 bytes, or as a | |
1422 | LEB128. This is encoded in bits 0, 1 and 2. Bit 3 encodes whether | |
1423 | the address is signed or unsigned. Bits 4, 5 and 6 encode how the | |
1424 | address should be interpreted (absolute, relative to the current | |
1425 | position in the FDE, ...). Bit 7, indicates that the address | |
1426 | should be dereferenced. */ | |
1427 | ||
852483bc | 1428 | static gdb_byte |
cfc14b3a MK |
1429 | encoding_for_size (unsigned int size) |
1430 | { | |
1431 | switch (size) | |
1432 | { | |
1433 | case 2: | |
1434 | return DW_EH_PE_udata2; | |
1435 | case 4: | |
1436 | return DW_EH_PE_udata4; | |
1437 | case 8: | |
1438 | return DW_EH_PE_udata8; | |
1439 | default: | |
e2e0b3e5 | 1440 | internal_error (__FILE__, __LINE__, _("Unsupported address size")); |
cfc14b3a MK |
1441 | } |
1442 | } | |
1443 | ||
cfc14b3a | 1444 | static CORE_ADDR |
852483bc | 1445 | read_encoded_value (struct comp_unit *unit, gdb_byte encoding, |
0d45f56e TT |
1446 | int ptr_len, const gdb_byte *buf, |
1447 | unsigned int *bytes_read_ptr, | |
ae0d2f24 | 1448 | CORE_ADDR func_base) |
cfc14b3a | 1449 | { |
68f6cf99 | 1450 | ptrdiff_t offset; |
cfc14b3a MK |
1451 | CORE_ADDR base; |
1452 | ||
1453 | /* GCC currently doesn't generate DW_EH_PE_indirect encodings for | |
1454 | FDE's. */ | |
1455 | if (encoding & DW_EH_PE_indirect) | |
1456 | internal_error (__FILE__, __LINE__, | |
e2e0b3e5 | 1457 | _("Unsupported encoding: DW_EH_PE_indirect")); |
cfc14b3a | 1458 | |
68f6cf99 MK |
1459 | *bytes_read_ptr = 0; |
1460 | ||
cfc14b3a MK |
1461 | switch (encoding & 0x70) |
1462 | { | |
1463 | case DW_EH_PE_absptr: | |
1464 | base = 0; | |
1465 | break; | |
1466 | case DW_EH_PE_pcrel: | |
f2fec864 | 1467 | base = bfd_get_section_vma (unit->abfd, unit->dwarf_frame_section); |
852483bc | 1468 | base += (buf - unit->dwarf_frame_buffer); |
cfc14b3a | 1469 | break; |
0912c7f2 MK |
1470 | case DW_EH_PE_datarel: |
1471 | base = unit->dbase; | |
1472 | break; | |
0fd85043 CV |
1473 | case DW_EH_PE_textrel: |
1474 | base = unit->tbase; | |
1475 | break; | |
03ac2a74 | 1476 | case DW_EH_PE_funcrel: |
ae0d2f24 | 1477 | base = func_base; |
03ac2a74 | 1478 | break; |
68f6cf99 MK |
1479 | case DW_EH_PE_aligned: |
1480 | base = 0; | |
852483bc | 1481 | offset = buf - unit->dwarf_frame_buffer; |
68f6cf99 MK |
1482 | if ((offset % ptr_len) != 0) |
1483 | { | |
1484 | *bytes_read_ptr = ptr_len - (offset % ptr_len); | |
1485 | buf += *bytes_read_ptr; | |
1486 | } | |
1487 | break; | |
cfc14b3a | 1488 | default: |
e2e0b3e5 | 1489 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1490 | } |
1491 | ||
b04de778 | 1492 | if ((encoding & 0x07) == 0x00) |
f2fec864 DJ |
1493 | { |
1494 | encoding |= encoding_for_size (ptr_len); | |
1495 | if (bfd_get_sign_extend_vma (unit->abfd)) | |
1496 | encoding |= DW_EH_PE_signed; | |
1497 | } | |
cfc14b3a MK |
1498 | |
1499 | switch (encoding & 0x0f) | |
1500 | { | |
a81b10ae MK |
1501 | case DW_EH_PE_uleb128: |
1502 | { | |
1503 | ULONGEST value; | |
0d45f56e | 1504 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1505 | |
a7289609 | 1506 | *bytes_read_ptr += read_uleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1507 | return base + value; |
1508 | } | |
cfc14b3a | 1509 | case DW_EH_PE_udata2: |
68f6cf99 | 1510 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1511 | return (base + bfd_get_16 (unit->abfd, (bfd_byte *) buf)); |
1512 | case DW_EH_PE_udata4: | |
68f6cf99 | 1513 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1514 | return (base + bfd_get_32 (unit->abfd, (bfd_byte *) buf)); |
1515 | case DW_EH_PE_udata8: | |
68f6cf99 | 1516 | *bytes_read_ptr += 8; |
cfc14b3a | 1517 | return (base + bfd_get_64 (unit->abfd, (bfd_byte *) buf)); |
a81b10ae MK |
1518 | case DW_EH_PE_sleb128: |
1519 | { | |
1520 | LONGEST value; | |
0d45f56e | 1521 | const gdb_byte *end_buf = buf + (sizeof (value) + 1) * 8 / 7; |
9a619af0 | 1522 | |
a7289609 | 1523 | *bytes_read_ptr += read_sleb128 (buf, end_buf, &value) - buf; |
a81b10ae MK |
1524 | return base + value; |
1525 | } | |
cfc14b3a | 1526 | case DW_EH_PE_sdata2: |
68f6cf99 | 1527 | *bytes_read_ptr += 2; |
cfc14b3a MK |
1528 | return (base + bfd_get_signed_16 (unit->abfd, (bfd_byte *) buf)); |
1529 | case DW_EH_PE_sdata4: | |
68f6cf99 | 1530 | *bytes_read_ptr += 4; |
cfc14b3a MK |
1531 | return (base + bfd_get_signed_32 (unit->abfd, (bfd_byte *) buf)); |
1532 | case DW_EH_PE_sdata8: | |
68f6cf99 | 1533 | *bytes_read_ptr += 8; |
cfc14b3a MK |
1534 | return (base + bfd_get_signed_64 (unit->abfd, (bfd_byte *) buf)); |
1535 | default: | |
e2e0b3e5 | 1536 | internal_error (__FILE__, __LINE__, _("Invalid or unsupported encoding")); |
cfc14b3a MK |
1537 | } |
1538 | } | |
1539 | \f | |
1540 | ||
b01c8410 PP |
1541 | static int |
1542 | bsearch_cie_cmp (const void *key, const void *element) | |
cfc14b3a | 1543 | { |
b01c8410 PP |
1544 | ULONGEST cie_pointer = *(ULONGEST *) key; |
1545 | struct dwarf2_cie *cie = *(struct dwarf2_cie **) element; | |
cfc14b3a | 1546 | |
b01c8410 PP |
1547 | if (cie_pointer == cie->cie_pointer) |
1548 | return 0; | |
cfc14b3a | 1549 | |
b01c8410 PP |
1550 | return (cie_pointer < cie->cie_pointer) ? -1 : 1; |
1551 | } | |
1552 | ||
1553 | /* Find CIE with the given CIE_POINTER in CIE_TABLE. */ | |
1554 | static struct dwarf2_cie * | |
1555 | find_cie (struct dwarf2_cie_table *cie_table, ULONGEST cie_pointer) | |
1556 | { | |
1557 | struct dwarf2_cie **p_cie; | |
cfc14b3a | 1558 | |
65a97ab3 PP |
1559 | /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to |
1560 | bsearch be non-NULL. */ | |
1561 | if (cie_table->entries == NULL) | |
1562 | { | |
1563 | gdb_assert (cie_table->num_entries == 0); | |
1564 | return NULL; | |
1565 | } | |
1566 | ||
b01c8410 PP |
1567 | p_cie = bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries, |
1568 | sizeof (cie_table->entries[0]), bsearch_cie_cmp); | |
1569 | if (p_cie != NULL) | |
1570 | return *p_cie; | |
cfc14b3a MK |
1571 | return NULL; |
1572 | } | |
1573 | ||
b01c8410 | 1574 | /* Add a pointer to new CIE to the CIE_TABLE, allocating space for it. */ |
cfc14b3a | 1575 | static void |
b01c8410 | 1576 | add_cie (struct dwarf2_cie_table *cie_table, struct dwarf2_cie *cie) |
cfc14b3a | 1577 | { |
b01c8410 PP |
1578 | const int n = cie_table->num_entries; |
1579 | ||
1580 | gdb_assert (n < 1 | |
1581 | || cie_table->entries[n - 1]->cie_pointer < cie->cie_pointer); | |
1582 | ||
1583 | cie_table->entries = | |
1584 | xrealloc (cie_table->entries, (n + 1) * sizeof (cie_table->entries[0])); | |
1585 | cie_table->entries[n] = cie; | |
1586 | cie_table->num_entries = n + 1; | |
1587 | } | |
1588 | ||
1589 | static int | |
1590 | bsearch_fde_cmp (const void *key, const void *element) | |
1591 | { | |
1592 | CORE_ADDR seek_pc = *(CORE_ADDR *) key; | |
1593 | struct dwarf2_fde *fde = *(struct dwarf2_fde **) element; | |
9a619af0 | 1594 | |
b01c8410 PP |
1595 | if (seek_pc < fde->initial_location) |
1596 | return -1; | |
1597 | if (seek_pc < fde->initial_location + fde->address_range) | |
1598 | return 0; | |
1599 | return 1; | |
cfc14b3a MK |
1600 | } |
1601 | ||
1602 | /* Find the FDE for *PC. Return a pointer to the FDE, and store the | |
1603 | inital location associated with it into *PC. */ | |
1604 | ||
1605 | static struct dwarf2_fde * | |
ac56253d | 1606 | dwarf2_frame_find_fde (CORE_ADDR *pc, CORE_ADDR *out_offset) |
cfc14b3a MK |
1607 | { |
1608 | struct objfile *objfile; | |
1609 | ||
1610 | ALL_OBJFILES (objfile) | |
1611 | { | |
b01c8410 PP |
1612 | struct dwarf2_fde_table *fde_table; |
1613 | struct dwarf2_fde **p_fde; | |
cfc14b3a | 1614 | CORE_ADDR offset; |
b01c8410 | 1615 | CORE_ADDR seek_pc; |
cfc14b3a | 1616 | |
b01c8410 PP |
1617 | fde_table = objfile_data (objfile, dwarf2_frame_objfile_data); |
1618 | if (fde_table == NULL) | |
be391dca TT |
1619 | { |
1620 | dwarf2_build_frame_info (objfile); | |
1621 | fde_table = objfile_data (objfile, dwarf2_frame_objfile_data); | |
1622 | } | |
1623 | gdb_assert (fde_table != NULL); | |
1624 | ||
1625 | if (fde_table->num_entries == 0) | |
4ae9ee8e DJ |
1626 | continue; |
1627 | ||
1628 | gdb_assert (objfile->section_offsets); | |
1629 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); | |
1630 | ||
b01c8410 PP |
1631 | gdb_assert (fde_table->num_entries > 0); |
1632 | if (*pc < offset + fde_table->entries[0]->initial_location) | |
1633 | continue; | |
1634 | ||
1635 | seek_pc = *pc - offset; | |
1636 | p_fde = bsearch (&seek_pc, fde_table->entries, fde_table->num_entries, | |
1637 | sizeof (fde_table->entries[0]), bsearch_fde_cmp); | |
1638 | if (p_fde != NULL) | |
1639 | { | |
1640 | *pc = (*p_fde)->initial_location + offset; | |
ac56253d TT |
1641 | if (out_offset) |
1642 | *out_offset = offset; | |
b01c8410 PP |
1643 | return *p_fde; |
1644 | } | |
cfc14b3a | 1645 | } |
cfc14b3a MK |
1646 | return NULL; |
1647 | } | |
1648 | ||
b01c8410 | 1649 | /* Add a pointer to new FDE to the FDE_TABLE, allocating space for it. */ |
cfc14b3a | 1650 | static void |
b01c8410 | 1651 | add_fde (struct dwarf2_fde_table *fde_table, struct dwarf2_fde *fde) |
cfc14b3a | 1652 | { |
b01c8410 PP |
1653 | if (fde->address_range == 0) |
1654 | /* Discard useless FDEs. */ | |
1655 | return; | |
1656 | ||
1657 | fde_table->num_entries += 1; | |
1658 | fde_table->entries = | |
1659 | xrealloc (fde_table->entries, | |
1660 | fde_table->num_entries * sizeof (fde_table->entries[0])); | |
1661 | fde_table->entries[fde_table->num_entries - 1] = fde; | |
cfc14b3a MK |
1662 | } |
1663 | ||
1664 | #ifdef CC_HAS_LONG_LONG | |
1665 | #define DW64_CIE_ID 0xffffffffffffffffULL | |
1666 | #else | |
1667 | #define DW64_CIE_ID ~0 | |
1668 | #endif | |
1669 | ||
852483bc | 1670 | static gdb_byte *decode_frame_entry (struct comp_unit *unit, gdb_byte *start, |
b01c8410 PP |
1671 | int eh_frame_p, |
1672 | struct dwarf2_cie_table *cie_table, | |
1673 | struct dwarf2_fde_table *fde_table); | |
cfc14b3a | 1674 | |
6896c0c7 RH |
1675 | /* Decode the next CIE or FDE. Return NULL if invalid input, otherwise |
1676 | the next byte to be processed. */ | |
852483bc | 1677 | static gdb_byte * |
b01c8410 PP |
1678 | decode_frame_entry_1 (struct comp_unit *unit, gdb_byte *start, int eh_frame_p, |
1679 | struct dwarf2_cie_table *cie_table, | |
1680 | struct dwarf2_fde_table *fde_table) | |
cfc14b3a | 1681 | { |
5e2b427d | 1682 | struct gdbarch *gdbarch = get_objfile_arch (unit->objfile); |
852483bc | 1683 | gdb_byte *buf, *end; |
cfc14b3a MK |
1684 | LONGEST length; |
1685 | unsigned int bytes_read; | |
6896c0c7 RH |
1686 | int dwarf64_p; |
1687 | ULONGEST cie_id; | |
cfc14b3a | 1688 | ULONGEST cie_pointer; |
cfc14b3a | 1689 | |
6896c0c7 | 1690 | buf = start; |
cfc14b3a MK |
1691 | length = read_initial_length (unit->abfd, buf, &bytes_read); |
1692 | buf += bytes_read; | |
1693 | end = buf + length; | |
1694 | ||
6896c0c7 RH |
1695 | /* Are we still within the section? */ |
1696 | if (end > unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
1697 | return NULL; | |
1698 | ||
cfc14b3a MK |
1699 | if (length == 0) |
1700 | return end; | |
1701 | ||
6896c0c7 RH |
1702 | /* Distinguish between 32 and 64-bit encoded frame info. */ |
1703 | dwarf64_p = (bytes_read == 12); | |
cfc14b3a | 1704 | |
6896c0c7 | 1705 | /* In a .eh_frame section, zero is used to distinguish CIEs from FDEs. */ |
cfc14b3a MK |
1706 | if (eh_frame_p) |
1707 | cie_id = 0; | |
1708 | else if (dwarf64_p) | |
1709 | cie_id = DW64_CIE_ID; | |
6896c0c7 RH |
1710 | else |
1711 | cie_id = DW_CIE_ID; | |
cfc14b3a MK |
1712 | |
1713 | if (dwarf64_p) | |
1714 | { | |
1715 | cie_pointer = read_8_bytes (unit->abfd, buf); | |
1716 | buf += 8; | |
1717 | } | |
1718 | else | |
1719 | { | |
1720 | cie_pointer = read_4_bytes (unit->abfd, buf); | |
1721 | buf += 4; | |
1722 | } | |
1723 | ||
1724 | if (cie_pointer == cie_id) | |
1725 | { | |
1726 | /* This is a CIE. */ | |
1727 | struct dwarf2_cie *cie; | |
1728 | char *augmentation; | |
28ba0b33 | 1729 | unsigned int cie_version; |
cfc14b3a MK |
1730 | |
1731 | /* Record the offset into the .debug_frame section of this CIE. */ | |
1732 | cie_pointer = start - unit->dwarf_frame_buffer; | |
1733 | ||
1734 | /* Check whether we've already read it. */ | |
b01c8410 | 1735 | if (find_cie (cie_table, cie_pointer)) |
cfc14b3a MK |
1736 | return end; |
1737 | ||
1738 | cie = (struct dwarf2_cie *) | |
8b92e4d5 | 1739 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a MK |
1740 | sizeof (struct dwarf2_cie)); |
1741 | cie->initial_instructions = NULL; | |
1742 | cie->cie_pointer = cie_pointer; | |
1743 | ||
1744 | /* The encoding for FDE's in a normal .debug_frame section | |
32b05c07 MK |
1745 | depends on the target address size. */ |
1746 | cie->encoding = DW_EH_PE_absptr; | |
cfc14b3a | 1747 | |
56c987f6 AO |
1748 | /* We'll determine the final value later, but we need to |
1749 | initialize it conservatively. */ | |
1750 | cie->signal_frame = 0; | |
1751 | ||
cfc14b3a | 1752 | /* Check version number. */ |
28ba0b33 | 1753 | cie_version = read_1_byte (unit->abfd, buf); |
2dc7f7b3 | 1754 | if (cie_version != 1 && cie_version != 3 && cie_version != 4) |
6896c0c7 | 1755 | return NULL; |
303b6f5d | 1756 | cie->version = cie_version; |
cfc14b3a MK |
1757 | buf += 1; |
1758 | ||
1759 | /* Interpret the interesting bits of the augmentation. */ | |
303b6f5d | 1760 | cie->augmentation = augmentation = (char *) buf; |
852483bc | 1761 | buf += (strlen (augmentation) + 1); |
cfc14b3a | 1762 | |
303b6f5d DJ |
1763 | /* Ignore armcc augmentations. We only use them for quirks, |
1764 | and that doesn't happen until later. */ | |
1765 | if (strncmp (augmentation, "armcc", 5) == 0) | |
1766 | augmentation += strlen (augmentation); | |
1767 | ||
cfc14b3a MK |
1768 | /* The GCC 2.x "eh" augmentation has a pointer immediately |
1769 | following the augmentation string, so it must be handled | |
1770 | first. */ | |
1771 | if (augmentation[0] == 'e' && augmentation[1] == 'h') | |
1772 | { | |
1773 | /* Skip. */ | |
5e2b427d | 1774 | buf += gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; |
cfc14b3a MK |
1775 | augmentation += 2; |
1776 | } | |
1777 | ||
2dc7f7b3 TT |
1778 | if (cie->version >= 4) |
1779 | { | |
1780 | /* FIXME: check that this is the same as from the CU header. */ | |
1781 | cie->addr_size = read_1_byte (unit->abfd, buf); | |
1782 | ++buf; | |
1783 | cie->segment_size = read_1_byte (unit->abfd, buf); | |
1784 | ++buf; | |
1785 | } | |
1786 | else | |
1787 | { | |
8da614df | 1788 | cie->addr_size = gdbarch_dwarf2_addr_size (gdbarch); |
2dc7f7b3 TT |
1789 | cie->segment_size = 0; |
1790 | } | |
8da614df CV |
1791 | /* Address values in .eh_frame sections are defined to have the |
1792 | target's pointer size. Watchout: This breaks frame info for | |
1793 | targets with pointer size < address size, unless a .debug_frame | |
1794 | section exists as well. */ | |
1795 | if (eh_frame_p) | |
1796 | cie->ptr_size = gdbarch_ptr_bit (gdbarch) / TARGET_CHAR_BIT; | |
1797 | else | |
1798 | cie->ptr_size = cie->addr_size; | |
2dc7f7b3 | 1799 | |
cfc14b3a MK |
1800 | cie->code_alignment_factor = |
1801 | read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1802 | buf += bytes_read; | |
1803 | ||
1804 | cie->data_alignment_factor = | |
1805 | read_signed_leb128 (unit->abfd, buf, &bytes_read); | |
1806 | buf += bytes_read; | |
1807 | ||
28ba0b33 PB |
1808 | if (cie_version == 1) |
1809 | { | |
1810 | cie->return_address_register = read_1_byte (unit->abfd, buf); | |
1811 | bytes_read = 1; | |
1812 | } | |
1813 | else | |
1814 | cie->return_address_register = read_unsigned_leb128 (unit->abfd, buf, | |
1815 | &bytes_read); | |
4fc771b8 | 1816 | cie->return_address_register |
5e2b427d | 1817 | = dwarf2_frame_adjust_regnum (gdbarch, |
4fc771b8 DJ |
1818 | cie->return_address_register, |
1819 | eh_frame_p); | |
4bf8967c | 1820 | |
28ba0b33 | 1821 | buf += bytes_read; |
cfc14b3a | 1822 | |
7131cb6e RH |
1823 | cie->saw_z_augmentation = (*augmentation == 'z'); |
1824 | if (cie->saw_z_augmentation) | |
cfc14b3a MK |
1825 | { |
1826 | ULONGEST length; | |
1827 | ||
1828 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1829 | buf += bytes_read; | |
6896c0c7 RH |
1830 | if (buf > end) |
1831 | return NULL; | |
cfc14b3a MK |
1832 | cie->initial_instructions = buf + length; |
1833 | augmentation++; | |
1834 | } | |
1835 | ||
1836 | while (*augmentation) | |
1837 | { | |
1838 | /* "L" indicates a byte showing how the LSDA pointer is encoded. */ | |
1839 | if (*augmentation == 'L') | |
1840 | { | |
1841 | /* Skip. */ | |
1842 | buf++; | |
1843 | augmentation++; | |
1844 | } | |
1845 | ||
1846 | /* "R" indicates a byte indicating how FDE addresses are encoded. */ | |
1847 | else if (*augmentation == 'R') | |
1848 | { | |
1849 | cie->encoding = *buf++; | |
1850 | augmentation++; | |
1851 | } | |
1852 | ||
1853 | /* "P" indicates a personality routine in the CIE augmentation. */ | |
1854 | else if (*augmentation == 'P') | |
1855 | { | |
1234d960 | 1856 | /* Skip. Avoid indirection since we throw away the result. */ |
852483bc | 1857 | gdb_byte encoding = (*buf++) & ~DW_EH_PE_indirect; |
8da614df | 1858 | read_encoded_value (unit, encoding, cie->ptr_size, |
ae0d2f24 | 1859 | buf, &bytes_read, 0); |
f724bf08 | 1860 | buf += bytes_read; |
cfc14b3a MK |
1861 | augmentation++; |
1862 | } | |
1863 | ||
56c987f6 AO |
1864 | /* "S" indicates a signal frame, such that the return |
1865 | address must not be decremented to locate the call frame | |
1866 | info for the previous frame; it might even be the first | |
1867 | instruction of a function, so decrementing it would take | |
1868 | us to a different function. */ | |
1869 | else if (*augmentation == 'S') | |
1870 | { | |
1871 | cie->signal_frame = 1; | |
1872 | augmentation++; | |
1873 | } | |
1874 | ||
3e9a2e52 DJ |
1875 | /* Otherwise we have an unknown augmentation. Assume that either |
1876 | there is no augmentation data, or we saw a 'z' prefix. */ | |
cfc14b3a MK |
1877 | else |
1878 | { | |
3e9a2e52 DJ |
1879 | if (cie->initial_instructions) |
1880 | buf = cie->initial_instructions; | |
cfc14b3a MK |
1881 | break; |
1882 | } | |
1883 | } | |
1884 | ||
1885 | cie->initial_instructions = buf; | |
1886 | cie->end = end; | |
b01c8410 | 1887 | cie->unit = unit; |
cfc14b3a | 1888 | |
b01c8410 | 1889 | add_cie (cie_table, cie); |
cfc14b3a MK |
1890 | } |
1891 | else | |
1892 | { | |
1893 | /* This is a FDE. */ | |
1894 | struct dwarf2_fde *fde; | |
1895 | ||
6896c0c7 RH |
1896 | /* In an .eh_frame section, the CIE pointer is the delta between the |
1897 | address within the FDE where the CIE pointer is stored and the | |
1898 | address of the CIE. Convert it to an offset into the .eh_frame | |
1899 | section. */ | |
cfc14b3a MK |
1900 | if (eh_frame_p) |
1901 | { | |
cfc14b3a MK |
1902 | cie_pointer = buf - unit->dwarf_frame_buffer - cie_pointer; |
1903 | cie_pointer -= (dwarf64_p ? 8 : 4); | |
1904 | } | |
1905 | ||
6896c0c7 RH |
1906 | /* In either case, validate the result is still within the section. */ |
1907 | if (cie_pointer >= unit->dwarf_frame_size) | |
1908 | return NULL; | |
1909 | ||
cfc14b3a | 1910 | fde = (struct dwarf2_fde *) |
8b92e4d5 | 1911 | obstack_alloc (&unit->objfile->objfile_obstack, |
cfc14b3a | 1912 | sizeof (struct dwarf2_fde)); |
b01c8410 | 1913 | fde->cie = find_cie (cie_table, cie_pointer); |
cfc14b3a MK |
1914 | if (fde->cie == NULL) |
1915 | { | |
1916 | decode_frame_entry (unit, unit->dwarf_frame_buffer + cie_pointer, | |
b01c8410 PP |
1917 | eh_frame_p, cie_table, fde_table); |
1918 | fde->cie = find_cie (cie_table, cie_pointer); | |
cfc14b3a MK |
1919 | } |
1920 | ||
1921 | gdb_assert (fde->cie != NULL); | |
1922 | ||
1923 | fde->initial_location = | |
8da614df | 1924 | read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, |
ae0d2f24 | 1925 | buf, &bytes_read, 0); |
cfc14b3a MK |
1926 | buf += bytes_read; |
1927 | ||
1928 | fde->address_range = | |
ae0d2f24 | 1929 | read_encoded_value (unit, fde->cie->encoding & 0x0f, |
8da614df | 1930 | fde->cie->ptr_size, buf, &bytes_read, 0); |
cfc14b3a MK |
1931 | buf += bytes_read; |
1932 | ||
7131cb6e RH |
1933 | /* A 'z' augmentation in the CIE implies the presence of an |
1934 | augmentation field in the FDE as well. The only thing known | |
1935 | to be in here at present is the LSDA entry for EH. So we | |
1936 | can skip the whole thing. */ | |
1937 | if (fde->cie->saw_z_augmentation) | |
1938 | { | |
1939 | ULONGEST length; | |
1940 | ||
1941 | length = read_unsigned_leb128 (unit->abfd, buf, &bytes_read); | |
1942 | buf += bytes_read + length; | |
6896c0c7 RH |
1943 | if (buf > end) |
1944 | return NULL; | |
7131cb6e RH |
1945 | } |
1946 | ||
cfc14b3a MK |
1947 | fde->instructions = buf; |
1948 | fde->end = end; | |
1949 | ||
4bf8967c AS |
1950 | fde->eh_frame_p = eh_frame_p; |
1951 | ||
b01c8410 | 1952 | add_fde (fde_table, fde); |
cfc14b3a MK |
1953 | } |
1954 | ||
1955 | return end; | |
1956 | } | |
6896c0c7 RH |
1957 | |
1958 | /* Read a CIE or FDE in BUF and decode it. */ | |
852483bc | 1959 | static gdb_byte * |
b01c8410 PP |
1960 | decode_frame_entry (struct comp_unit *unit, gdb_byte *start, int eh_frame_p, |
1961 | struct dwarf2_cie_table *cie_table, | |
1962 | struct dwarf2_fde_table *fde_table) | |
6896c0c7 RH |
1963 | { |
1964 | enum { NONE, ALIGN4, ALIGN8, FAIL } workaround = NONE; | |
852483bc | 1965 | gdb_byte *ret; |
6896c0c7 RH |
1966 | ptrdiff_t start_offset; |
1967 | ||
1968 | while (1) | |
1969 | { | |
b01c8410 PP |
1970 | ret = decode_frame_entry_1 (unit, start, eh_frame_p, |
1971 | cie_table, fde_table); | |
6896c0c7 RH |
1972 | if (ret != NULL) |
1973 | break; | |
1974 | ||
1975 | /* We have corrupt input data of some form. */ | |
1976 | ||
1977 | /* ??? Try, weakly, to work around compiler/assembler/linker bugs | |
1978 | and mismatches wrt padding and alignment of debug sections. */ | |
1979 | /* Note that there is no requirement in the standard for any | |
1980 | alignment at all in the frame unwind sections. Testing for | |
1981 | alignment before trying to interpret data would be incorrect. | |
1982 | ||
1983 | However, GCC traditionally arranged for frame sections to be | |
1984 | sized such that the FDE length and CIE fields happen to be | |
1985 | aligned (in theory, for performance). This, unfortunately, | |
1986 | was done with .align directives, which had the side effect of | |
1987 | forcing the section to be aligned by the linker. | |
1988 | ||
1989 | This becomes a problem when you have some other producer that | |
1990 | creates frame sections that are not as strictly aligned. That | |
1991 | produces a hole in the frame info that gets filled by the | |
1992 | linker with zeros. | |
1993 | ||
1994 | The GCC behaviour is arguably a bug, but it's effectively now | |
1995 | part of the ABI, so we're now stuck with it, at least at the | |
1996 | object file level. A smart linker may decide, in the process | |
1997 | of compressing duplicate CIE information, that it can rewrite | |
1998 | the entire output section without this extra padding. */ | |
1999 | ||
2000 | start_offset = start - unit->dwarf_frame_buffer; | |
2001 | if (workaround < ALIGN4 && (start_offset & 3) != 0) | |
2002 | { | |
2003 | start += 4 - (start_offset & 3); | |
2004 | workaround = ALIGN4; | |
2005 | continue; | |
2006 | } | |
2007 | if (workaround < ALIGN8 && (start_offset & 7) != 0) | |
2008 | { | |
2009 | start += 8 - (start_offset & 7); | |
2010 | workaround = ALIGN8; | |
2011 | continue; | |
2012 | } | |
2013 | ||
2014 | /* Nothing left to try. Arrange to return as if we've consumed | |
2015 | the entire input section. Hopefully we'll get valid info from | |
2016 | the other of .debug_frame/.eh_frame. */ | |
2017 | workaround = FAIL; | |
2018 | ret = unit->dwarf_frame_buffer + unit->dwarf_frame_size; | |
2019 | break; | |
2020 | } | |
2021 | ||
2022 | switch (workaround) | |
2023 | { | |
2024 | case NONE: | |
2025 | break; | |
2026 | ||
2027 | case ALIGN4: | |
2028 | complaint (&symfile_complaints, | |
e2e0b3e5 | 2029 | _("Corrupt data in %s:%s; align 4 workaround apparently succeeded"), |
6896c0c7 RH |
2030 | unit->dwarf_frame_section->owner->filename, |
2031 | unit->dwarf_frame_section->name); | |
2032 | break; | |
2033 | ||
2034 | case ALIGN8: | |
2035 | complaint (&symfile_complaints, | |
e2e0b3e5 | 2036 | _("Corrupt data in %s:%s; align 8 workaround apparently succeeded"), |
6896c0c7 RH |
2037 | unit->dwarf_frame_section->owner->filename, |
2038 | unit->dwarf_frame_section->name); | |
2039 | break; | |
2040 | ||
2041 | default: | |
2042 | complaint (&symfile_complaints, | |
e2e0b3e5 | 2043 | _("Corrupt data in %s:%s"), |
6896c0c7 RH |
2044 | unit->dwarf_frame_section->owner->filename, |
2045 | unit->dwarf_frame_section->name); | |
2046 | break; | |
2047 | } | |
2048 | ||
2049 | return ret; | |
2050 | } | |
cfc14b3a MK |
2051 | \f |
2052 | ||
cfc14b3a | 2053 | /* Imported from dwarf2read.c. */ |
dce234bc PP |
2054 | extern void dwarf2_get_section_info (struct objfile *, const char *, asection **, |
2055 | gdb_byte **, bfd_size_type *); | |
cfc14b3a | 2056 | |
b01c8410 PP |
2057 | static int |
2058 | qsort_fde_cmp (const void *a, const void *b) | |
2059 | { | |
2060 | struct dwarf2_fde *aa = *(struct dwarf2_fde **)a; | |
2061 | struct dwarf2_fde *bb = *(struct dwarf2_fde **)b; | |
e5af178f | 2062 | |
b01c8410 | 2063 | if (aa->initial_location == bb->initial_location) |
e5af178f PP |
2064 | { |
2065 | if (aa->address_range != bb->address_range | |
2066 | && aa->eh_frame_p == 0 && bb->eh_frame_p == 0) | |
2067 | /* Linker bug, e.g. gold/10400. | |
2068 | Work around it by keeping stable sort order. */ | |
2069 | return (a < b) ? -1 : 1; | |
2070 | else | |
2071 | /* Put eh_frame entries after debug_frame ones. */ | |
2072 | return aa->eh_frame_p - bb->eh_frame_p; | |
2073 | } | |
b01c8410 PP |
2074 | |
2075 | return (aa->initial_location < bb->initial_location) ? -1 : 1; | |
2076 | } | |
2077 | ||
cfc14b3a MK |
2078 | void |
2079 | dwarf2_build_frame_info (struct objfile *objfile) | |
2080 | { | |
ae0d2f24 | 2081 | struct comp_unit *unit; |
852483bc | 2082 | gdb_byte *frame_ptr; |
b01c8410 PP |
2083 | struct dwarf2_cie_table cie_table; |
2084 | struct dwarf2_fde_table fde_table; | |
be391dca | 2085 | struct dwarf2_fde_table *fde_table2; |
b01c8410 PP |
2086 | |
2087 | cie_table.num_entries = 0; | |
2088 | cie_table.entries = NULL; | |
2089 | ||
2090 | fde_table.num_entries = 0; | |
2091 | fde_table.entries = NULL; | |
cfc14b3a MK |
2092 | |
2093 | /* Build a minimal decoding of the DWARF2 compilation unit. */ | |
ae0d2f24 UW |
2094 | unit = (struct comp_unit *) obstack_alloc (&objfile->objfile_obstack, |
2095 | sizeof (struct comp_unit)); | |
2096 | unit->abfd = objfile->obfd; | |
2097 | unit->objfile = objfile; | |
2098 | unit->dbase = 0; | |
2099 | unit->tbase = 0; | |
cfc14b3a | 2100 | |
dce234bc PP |
2101 | dwarf2_get_section_info (objfile, ".eh_frame", |
2102 | &unit->dwarf_frame_section, | |
2103 | &unit->dwarf_frame_buffer, | |
2104 | &unit->dwarf_frame_size); | |
2105 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2106 | { |
0fd85043 | 2107 | asection *got, *txt; |
0912c7f2 | 2108 | |
0912c7f2 | 2109 | /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base |
37b517aa MK |
2110 | that is used for the i386/amd64 target, which currently is |
2111 | the only target in GCC that supports/uses the | |
2112 | DW_EH_PE_datarel encoding. */ | |
ae0d2f24 | 2113 | got = bfd_get_section_by_name (unit->abfd, ".got"); |
0912c7f2 | 2114 | if (got) |
ae0d2f24 | 2115 | unit->dbase = got->vma; |
0912c7f2 | 2116 | |
22c7ba1a MK |
2117 | /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64 |
2118 | so far. */ | |
ae0d2f24 | 2119 | txt = bfd_get_section_by_name (unit->abfd, ".text"); |
0fd85043 | 2120 | if (txt) |
ae0d2f24 | 2121 | unit->tbase = txt->vma; |
0fd85043 | 2122 | |
ae0d2f24 UW |
2123 | frame_ptr = unit->dwarf_frame_buffer; |
2124 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
b01c8410 PP |
2125 | frame_ptr = decode_frame_entry (unit, frame_ptr, 1, |
2126 | &cie_table, &fde_table); | |
2127 | ||
2128 | if (cie_table.num_entries != 0) | |
2129 | { | |
2130 | /* Reinit cie_table: debug_frame has different CIEs. */ | |
2131 | xfree (cie_table.entries); | |
2132 | cie_table.num_entries = 0; | |
2133 | cie_table.entries = NULL; | |
2134 | } | |
cfc14b3a MK |
2135 | } |
2136 | ||
dce234bc PP |
2137 | dwarf2_get_section_info (objfile, ".debug_frame", |
2138 | &unit->dwarf_frame_section, | |
2139 | &unit->dwarf_frame_buffer, | |
2140 | &unit->dwarf_frame_size); | |
2141 | if (unit->dwarf_frame_size) | |
cfc14b3a | 2142 | { |
ae0d2f24 UW |
2143 | frame_ptr = unit->dwarf_frame_buffer; |
2144 | while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size) | |
b01c8410 PP |
2145 | frame_ptr = decode_frame_entry (unit, frame_ptr, 0, |
2146 | &cie_table, &fde_table); | |
2147 | } | |
2148 | ||
2149 | /* Discard the cie_table, it is no longer needed. */ | |
2150 | if (cie_table.num_entries != 0) | |
2151 | { | |
2152 | xfree (cie_table.entries); | |
2153 | cie_table.entries = NULL; /* Paranoia. */ | |
2154 | cie_table.num_entries = 0; /* Paranoia. */ | |
2155 | } | |
2156 | ||
be391dca TT |
2157 | /* Copy fde_table to obstack: it is needed at runtime. */ |
2158 | fde_table2 = (struct dwarf2_fde_table *) | |
2159 | obstack_alloc (&objfile->objfile_obstack, sizeof (*fde_table2)); | |
2160 | ||
2161 | if (fde_table.num_entries == 0) | |
2162 | { | |
2163 | fde_table2->entries = NULL; | |
2164 | fde_table2->num_entries = 0; | |
2165 | } | |
2166 | else | |
b01c8410 | 2167 | { |
875cdfbb PA |
2168 | struct dwarf2_fde *fde_prev = NULL; |
2169 | struct dwarf2_fde *first_non_zero_fde = NULL; | |
2170 | int i; | |
b01c8410 PP |
2171 | |
2172 | /* Prepare FDE table for lookups. */ | |
2173 | qsort (fde_table.entries, fde_table.num_entries, | |
2174 | sizeof (fde_table.entries[0]), qsort_fde_cmp); | |
2175 | ||
875cdfbb PA |
2176 | /* Check for leftovers from --gc-sections. The GNU linker sets |
2177 | the relevant symbols to zero, but doesn't zero the FDE *end* | |
2178 | ranges because there's no relocation there. It's (offset, | |
2179 | length), not (start, end). On targets where address zero is | |
2180 | just another valid address this can be a problem, since the | |
2181 | FDEs appear to be non-empty in the output --- we could pick | |
2182 | out the wrong FDE. To work around this, when overlaps are | |
2183 | detected, we prefer FDEs that do not start at zero. | |
2184 | ||
2185 | Start by finding the first FDE with non-zero start. Below | |
2186 | we'll discard all FDEs that start at zero and overlap this | |
2187 | one. */ | |
2188 | for (i = 0; i < fde_table.num_entries; i++) | |
2189 | { | |
2190 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
b01c8410 | 2191 | |
875cdfbb PA |
2192 | if (fde->initial_location != 0) |
2193 | { | |
2194 | first_non_zero_fde = fde; | |
2195 | break; | |
2196 | } | |
2197 | } | |
2198 | ||
2199 | /* Since we'll be doing bsearch, squeeze out identical (except | |
2200 | for eh_frame_p) fde entries so bsearch result is predictable. | |
2201 | Also discard leftovers from --gc-sections. */ | |
be391dca | 2202 | fde_table2->num_entries = 0; |
875cdfbb PA |
2203 | for (i = 0; i < fde_table.num_entries; i++) |
2204 | { | |
2205 | struct dwarf2_fde *fde = fde_table.entries[i]; | |
2206 | ||
2207 | if (fde->initial_location == 0 | |
2208 | && first_non_zero_fde != NULL | |
2209 | && (first_non_zero_fde->initial_location | |
2210 | < fde->initial_location + fde->address_range)) | |
2211 | continue; | |
2212 | ||
2213 | if (fde_prev != NULL | |
2214 | && fde_prev->initial_location == fde->initial_location) | |
2215 | continue; | |
2216 | ||
2217 | obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i], | |
2218 | sizeof (fde_table.entries[0])); | |
2219 | ++fde_table2->num_entries; | |
2220 | fde_prev = fde; | |
2221 | } | |
b01c8410 | 2222 | fde_table2->entries = obstack_finish (&objfile->objfile_obstack); |
b01c8410 PP |
2223 | |
2224 | /* Discard the original fde_table. */ | |
2225 | xfree (fde_table.entries); | |
cfc14b3a | 2226 | } |
be391dca TT |
2227 | |
2228 | set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2); | |
cfc14b3a | 2229 | } |
0d0e1a63 MK |
2230 | |
2231 | /* Provide a prototype to silence -Wmissing-prototypes. */ | |
2232 | void _initialize_dwarf2_frame (void); | |
2233 | ||
2234 | void | |
2235 | _initialize_dwarf2_frame (void) | |
2236 | { | |
030f20e1 | 2237 | dwarf2_frame_data = gdbarch_data_register_pre_init (dwarf2_frame_init); |
8f22cb90 | 2238 | dwarf2_frame_objfile_data = register_objfile_data (); |
0d0e1a63 | 2239 | } |