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7ed49443 JB |
1 | /* Abstraction of GNU v3 abi. |
2 | Contributed by Jim Blandy <jimb@redhat.com> | |
451fbdda | 3 | |
618f726f | 4 | Copyright (C) 2001-2016 Free Software Foundation, Inc. |
7ed49443 JB |
5 | |
6 | This file is part of GDB. | |
7 | ||
a9762ec7 JB |
8 | This program is free software; you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 3 of the License, or | |
11 | (at your option) any later version. | |
7ed49443 JB |
12 | |
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
7ed49443 JB |
20 | |
21 | #include "defs.h" | |
22 | #include "value.h" | |
23 | #include "cp-abi.h" | |
362ff856 | 24 | #include "cp-support.h" |
7ed49443 | 25 | #include "demangle.h" |
b18be20d | 26 | #include "objfiles.h" |
0d5de010 | 27 | #include "valprint.h" |
94af9270 | 28 | #include "c-lang.h" |
79d43c61 | 29 | #include "typeprint.h" |
0d5de010 | 30 | |
b27b8843 | 31 | static struct cp_abi_ops gnu_v3_abi_ops; |
7ed49443 | 32 | |
6e72ca20 TT |
33 | /* A gdbarch key for std::type_info, in the event that it can't be |
34 | found in the debug info. */ | |
35 | ||
36 | static struct gdbarch_data *std_type_info_gdbarch_data; | |
37 | ||
38 | ||
7ed49443 JB |
39 | static int |
40 | gnuv3_is_vtable_name (const char *name) | |
41 | { | |
61012eef | 42 | return startswith (name, "_ZTV"); |
7ed49443 JB |
43 | } |
44 | ||
45 | static int | |
46 | gnuv3_is_operator_name (const char *name) | |
47 | { | |
61012eef | 48 | return startswith (name, "operator"); |
7ed49443 JB |
49 | } |
50 | ||
51 | ||
52 | /* To help us find the components of a vtable, we build ourselves a | |
53 | GDB type object representing the vtable structure. Following the | |
54 | V3 ABI, it goes something like this: | |
55 | ||
56 | struct gdb_gnu_v3_abi_vtable { | |
57 | ||
58 | / * An array of virtual call and virtual base offsets. The real | |
59 | length of this array depends on the class hierarchy; we use | |
60 | negative subscripts to access the elements. Yucky, but | |
61 | better than the alternatives. * / | |
62 | ptrdiff_t vcall_and_vbase_offsets[0]; | |
63 | ||
64 | / * The offset from a virtual pointer referring to this table | |
65 | to the top of the complete object. * / | |
66 | ptrdiff_t offset_to_top; | |
67 | ||
68 | / * The type_info pointer for this class. This is really a | |
69 | std::type_info *, but GDB doesn't really look at the | |
70 | type_info object itself, so we don't bother to get the type | |
71 | exactly right. * / | |
72 | void *type_info; | |
73 | ||
74 | / * Virtual table pointers in objects point here. * / | |
75 | ||
76 | / * Virtual function pointers. Like the vcall/vbase array, the | |
77 | real length of this table depends on the class hierarchy. * / | |
78 | void (*virtual_functions[0]) (); | |
79 | ||
80 | }; | |
81 | ||
82 | The catch, of course, is that the exact layout of this table | |
83 | depends on the ABI --- word size, endianness, alignment, etc. So | |
84 | the GDB type object is actually a per-architecture kind of thing. | |
85 | ||
86 | vtable_type_gdbarch_data is a gdbarch per-architecture data pointer | |
87 | which refers to the struct type * for this structure, laid out | |
88 | appropriately for the architecture. */ | |
b27b8843 | 89 | static struct gdbarch_data *vtable_type_gdbarch_data; |
7ed49443 JB |
90 | |
91 | ||
92 | /* Human-readable names for the numbers of the fields above. */ | |
93 | enum { | |
94 | vtable_field_vcall_and_vbase_offsets, | |
95 | vtable_field_offset_to_top, | |
96 | vtable_field_type_info, | |
97 | vtable_field_virtual_functions | |
98 | }; | |
99 | ||
100 | ||
101 | /* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable', | |
102 | described above, laid out appropriately for ARCH. | |
103 | ||
104 | We use this function as the gdbarch per-architecture data | |
9970f04b | 105 | initialization function. */ |
7ed49443 JB |
106 | static void * |
107 | build_gdb_vtable_type (struct gdbarch *arch) | |
108 | { | |
109 | struct type *t; | |
110 | struct field *field_list, *field; | |
111 | int offset; | |
112 | ||
113 | struct type *void_ptr_type | |
fde6c819 | 114 | = builtin_type (arch)->builtin_data_ptr; |
7ed49443 | 115 | struct type *ptr_to_void_fn_type |
fde6c819 | 116 | = builtin_type (arch)->builtin_func_ptr; |
7ed49443 JB |
117 | |
118 | /* ARCH can't give us the true ptrdiff_t type, so we guess. */ | |
119 | struct type *ptrdiff_type | |
e9bb382b | 120 | = arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t"); |
7ed49443 JB |
121 | |
122 | /* We assume no padding is necessary, since GDB doesn't know | |
123 | anything about alignment at the moment. If this assumption bites | |
124 | us, we should add a gdbarch method which, given a type, returns | |
125 | the alignment that type requires, and then use that here. */ | |
126 | ||
127 | /* Build the field list. */ | |
8d749320 | 128 | field_list = XCNEWVEC (struct field, 4); |
7ed49443 JB |
129 | field = &field_list[0]; |
130 | offset = 0; | |
131 | ||
132 | /* ptrdiff_t vcall_and_vbase_offsets[0]; */ | |
133 | FIELD_NAME (*field) = "vcall_and_vbase_offsets"; | |
e3506a9f | 134 | FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1); |
f41f5e61 | 135 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
136 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
137 | field++; | |
138 | ||
139 | /* ptrdiff_t offset_to_top; */ | |
140 | FIELD_NAME (*field) = "offset_to_top"; | |
141 | FIELD_TYPE (*field) = ptrdiff_type; | |
f41f5e61 | 142 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
143 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
144 | field++; | |
145 | ||
146 | /* void *type_info; */ | |
147 | FIELD_NAME (*field) = "type_info"; | |
148 | FIELD_TYPE (*field) = void_ptr_type; | |
f41f5e61 | 149 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
150 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
151 | field++; | |
152 | ||
153 | /* void (*virtual_functions[0]) (); */ | |
154 | FIELD_NAME (*field) = "virtual_functions"; | |
e3506a9f | 155 | FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1); |
f41f5e61 | 156 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
157 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
158 | field++; | |
159 | ||
160 | /* We assumed in the allocation above that there were four fields. */ | |
3d499020 | 161 | gdb_assert (field == (field_list + 4)); |
7ed49443 | 162 | |
e9bb382b | 163 | t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL); |
7ed49443 JB |
164 | TYPE_NFIELDS (t) = field - field_list; |
165 | TYPE_FIELDS (t) = field_list; | |
166 | TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable"; | |
e9bb382b | 167 | INIT_CPLUS_SPECIFIC (t); |
7ed49443 | 168 | |
706d0883 | 169 | return make_type_with_address_space (t, TYPE_INSTANCE_FLAG_CODE_SPACE); |
7ed49443 JB |
170 | } |
171 | ||
172 | ||
ed09d7da KB |
173 | /* Return the ptrdiff_t type used in the vtable type. */ |
174 | static struct type * | |
175 | vtable_ptrdiff_type (struct gdbarch *gdbarch) | |
176 | { | |
9a3c8263 SM |
177 | struct type *vtable_type |
178 | = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data); | |
ed09d7da KB |
179 | |
180 | /* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */ | |
181 | return TYPE_FIELD_TYPE (vtable_type, vtable_field_offset_to_top); | |
182 | } | |
183 | ||
7ed49443 JB |
184 | /* Return the offset from the start of the imaginary `struct |
185 | gdb_gnu_v3_abi_vtable' object to the vtable's "address point" | |
186 | (i.e., where objects' virtual table pointers point). */ | |
187 | static int | |
ad4820ab | 188 | vtable_address_point_offset (struct gdbarch *gdbarch) |
7ed49443 | 189 | { |
9a3c8263 SM |
190 | struct type *vtable_type |
191 | = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data); | |
7ed49443 JB |
192 | |
193 | return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions) | |
194 | / TARGET_CHAR_BIT); | |
195 | } | |
196 | ||
197 | ||
d48cc9dd DJ |
198 | /* Determine whether structure TYPE is a dynamic class. Cache the |
199 | result. */ | |
200 | ||
201 | static int | |
202 | gnuv3_dynamic_class (struct type *type) | |
203 | { | |
204 | int fieldnum, fieldelem; | |
205 | ||
f168693b | 206 | type = check_typedef (type); |
5f4ce105 DE |
207 | gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT |
208 | || TYPE_CODE (type) == TYPE_CODE_UNION); | |
209 | ||
210 | if (TYPE_CODE (type) == TYPE_CODE_UNION) | |
211 | return 0; | |
212 | ||
d48cc9dd DJ |
213 | if (TYPE_CPLUS_DYNAMIC (type)) |
214 | return TYPE_CPLUS_DYNAMIC (type) == 1; | |
215 | ||
216 | ALLOCATE_CPLUS_STRUCT_TYPE (type); | |
217 | ||
218 | for (fieldnum = 0; fieldnum < TYPE_N_BASECLASSES (type); fieldnum++) | |
219 | if (BASETYPE_VIA_VIRTUAL (type, fieldnum) | |
220 | || gnuv3_dynamic_class (TYPE_FIELD_TYPE (type, fieldnum))) | |
221 | { | |
222 | TYPE_CPLUS_DYNAMIC (type) = 1; | |
223 | return 1; | |
224 | } | |
225 | ||
226 | for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++) | |
227 | for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum); | |
228 | fieldelem++) | |
229 | { | |
230 | struct fn_field *f = TYPE_FN_FIELDLIST1 (type, fieldnum); | |
231 | ||
232 | if (TYPE_FN_FIELD_VIRTUAL_P (f, fieldelem)) | |
233 | { | |
234 | TYPE_CPLUS_DYNAMIC (type) = 1; | |
235 | return 1; | |
236 | } | |
237 | } | |
238 | ||
239 | TYPE_CPLUS_DYNAMIC (type) = -1; | |
240 | return 0; | |
241 | } | |
242 | ||
243 | /* Find the vtable for a value of CONTAINER_TYPE located at | |
244 | CONTAINER_ADDR. Return a value of the correct vtable type for this | |
245 | architecture, or NULL if CONTAINER does not have a vtable. */ | |
246 | ||
247 | static struct value * | |
248 | gnuv3_get_vtable (struct gdbarch *gdbarch, | |
249 | struct type *container_type, CORE_ADDR container_addr) | |
250 | { | |
9a3c8263 SM |
251 | struct type *vtable_type |
252 | = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data); | |
d48cc9dd DJ |
253 | struct type *vtable_pointer_type; |
254 | struct value *vtable_pointer; | |
255 | CORE_ADDR vtable_address; | |
256 | ||
f168693b | 257 | container_type = check_typedef (container_type); |
5f4ce105 DE |
258 | gdb_assert (TYPE_CODE (container_type) == TYPE_CODE_STRUCT); |
259 | ||
d48cc9dd DJ |
260 | /* If this type does not have a virtual table, don't read the first |
261 | field. */ | |
5f4ce105 | 262 | if (!gnuv3_dynamic_class (container_type)) |
d48cc9dd DJ |
263 | return NULL; |
264 | ||
265 | /* We do not consult the debug information to find the virtual table. | |
266 | The ABI specifies that it is always at offset zero in any class, | |
267 | and debug information may not represent it. | |
268 | ||
269 | We avoid using value_contents on principle, because the object might | |
270 | be large. */ | |
271 | ||
272 | /* Find the type "pointer to virtual table". */ | |
273 | vtable_pointer_type = lookup_pointer_type (vtable_type); | |
274 | ||
275 | /* Load it from the start of the class. */ | |
276 | vtable_pointer = value_at (vtable_pointer_type, container_addr); | |
277 | vtable_address = value_as_address (vtable_pointer); | |
278 | ||
279 | /* Correct it to point at the start of the virtual table, rather | |
280 | than the address point. */ | |
281 | return value_at_lazy (vtable_type, | |
0963b4bd MS |
282 | vtable_address |
283 | - vtable_address_point_offset (gdbarch)); | |
d48cc9dd DJ |
284 | } |
285 | ||
286 | ||
7ed49443 JB |
287 | static struct type * |
288 | gnuv3_rtti_type (struct value *value, | |
289 | int *full_p, int *top_p, int *using_enc_p) | |
290 | { | |
ad4820ab | 291 | struct gdbarch *gdbarch; |
df407dfe | 292 | struct type *values_type = check_typedef (value_type (value)); |
7ed49443 JB |
293 | struct value *vtable; |
294 | struct minimal_symbol *vtable_symbol; | |
295 | const char *vtable_symbol_name; | |
296 | const char *class_name; | |
7ed49443 JB |
297 | struct type *run_time_type; |
298 | LONGEST offset_to_top; | |
e6a959d6 | 299 | const char *atsign; |
7ed49443 JB |
300 | |
301 | /* We only have RTTI for class objects. */ | |
4753d33b | 302 | if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT) |
7ed49443 JB |
303 | return NULL; |
304 | ||
eb2a6f42 TT |
305 | /* Java doesn't have RTTI following the C++ ABI. */ |
306 | if (TYPE_CPLUS_REALLY_JAVA (values_type)) | |
307 | return NULL; | |
308 | ||
ad4820ab | 309 | /* Determine architecture. */ |
50810684 | 310 | gdbarch = get_type_arch (values_type); |
7ed49443 | 311 | |
21cfb3b6 DJ |
312 | if (using_enc_p) |
313 | *using_enc_p = 0; | |
314 | ||
5f4ce105 | 315 | vtable = gnuv3_get_vtable (gdbarch, values_type, |
d48cc9dd DJ |
316 | value_as_address (value_addr (value))); |
317 | if (vtable == NULL) | |
318 | return NULL; | |
319 | ||
7ed49443 JB |
320 | /* Find the linker symbol for this vtable. */ |
321 | vtable_symbol | |
42ae5230 | 322 | = lookup_minimal_symbol_by_pc (value_address (vtable) |
7cbd4a93 | 323 | + value_embedded_offset (vtable)).minsym; |
7ed49443 JB |
324 | if (! vtable_symbol) |
325 | return NULL; | |
326 | ||
327 | /* The symbol's demangled name should be something like "vtable for | |
328 | CLASS", where CLASS is the name of the run-time type of VALUE. | |
329 | If we didn't like this approach, we could instead look in the | |
330 | type_info object itself to get the class name. But this way | |
331 | should work just as well, and doesn't read target memory. */ | |
efd66ac6 | 332 | vtable_symbol_name = MSYMBOL_DEMANGLED_NAME (vtable_symbol); |
98081e55 | 333 | if (vtable_symbol_name == NULL |
61012eef | 334 | || !startswith (vtable_symbol_name, "vtable for ")) |
f773fdbb | 335 | { |
8a3fe4f8 | 336 | warning (_("can't find linker symbol for virtual table for `%s' value"), |
0a07729b | 337 | TYPE_SAFE_NAME (values_type)); |
f773fdbb | 338 | if (vtable_symbol_name) |
8a3fe4f8 | 339 | warning (_(" found `%s' instead"), vtable_symbol_name); |
f773fdbb JM |
340 | return NULL; |
341 | } | |
7ed49443 JB |
342 | class_name = vtable_symbol_name + 11; |
343 | ||
8de20a37 TT |
344 | /* Strip off @plt and version suffixes. */ |
345 | atsign = strchr (class_name, '@'); | |
346 | if (atsign != NULL) | |
347 | { | |
348 | char *copy; | |
349 | ||
224c3ddb | 350 | copy = (char *) alloca (atsign - class_name + 1); |
8de20a37 TT |
351 | memcpy (copy, class_name, atsign - class_name); |
352 | copy[atsign - class_name] = '\0'; | |
353 | class_name = copy; | |
354 | } | |
355 | ||
7ed49443 | 356 | /* Try to look up the class name as a type name. */ |
0963b4bd | 357 | /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */ |
362ff856 MC |
358 | run_time_type = cp_lookup_rtti_type (class_name, NULL); |
359 | if (run_time_type == NULL) | |
360 | return NULL; | |
7ed49443 JB |
361 | |
362 | /* Get the offset from VALUE to the top of the complete object. | |
363 | NOTE: this is the reverse of the meaning of *TOP_P. */ | |
364 | offset_to_top | |
365 | = value_as_long (value_field (vtable, vtable_field_offset_to_top)); | |
366 | ||
367 | if (full_p) | |
13c3b5f5 | 368 | *full_p = (- offset_to_top == value_embedded_offset (value) |
4754a64e | 369 | && (TYPE_LENGTH (value_enclosing_type (value)) |
7ed49443 JB |
370 | >= TYPE_LENGTH (run_time_type))); |
371 | if (top_p) | |
372 | *top_p = - offset_to_top; | |
7ed49443 JB |
373 | return run_time_type; |
374 | } | |
375 | ||
0d5de010 DJ |
376 | /* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual |
377 | function, of type FNTYPE. */ | |
7ed49443 | 378 | |
0d5de010 | 379 | static struct value * |
ad4820ab UW |
380 | gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container, |
381 | struct type *fntype, int vtable_index) | |
0d5de010 | 382 | { |
d48cc9dd DJ |
383 | struct value *vtable, *vfn; |
384 | ||
385 | /* Every class with virtual functions must have a vtable. */ | |
386 | vtable = gnuv3_get_vtable (gdbarch, value_type (container), | |
387 | value_as_address (value_addr (container))); | |
388 | gdb_assert (vtable != NULL); | |
7ed49443 JB |
389 | |
390 | /* Fetch the appropriate function pointer from the vtable. */ | |
391 | vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions), | |
2497b498 | 392 | vtable_index); |
7ed49443 | 393 | |
0d5de010 DJ |
394 | /* If this architecture uses function descriptors directly in the vtable, |
395 | then the address of the vtable entry is actually a "function pointer" | |
396 | (i.e. points to the descriptor). We don't need to scale the index | |
397 | by the size of a function descriptor; GCC does that before outputing | |
398 | debug information. */ | |
ad4820ab | 399 | if (gdbarch_vtable_function_descriptors (gdbarch)) |
0d5de010 | 400 | vfn = value_addr (vfn); |
7ed49443 | 401 | |
0d5de010 DJ |
402 | /* Cast the function pointer to the appropriate type. */ |
403 | vfn = value_cast (lookup_pointer_type (fntype), vfn); | |
76b79d6e | 404 | |
7ed49443 JB |
405 | return vfn; |
406 | } | |
407 | ||
0d5de010 DJ |
408 | /* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h |
409 | for a description of the arguments. */ | |
410 | ||
411 | static struct value * | |
412 | gnuv3_virtual_fn_field (struct value **value_p, | |
413 | struct fn_field *f, int j, | |
414 | struct type *vfn_base, int offset) | |
415 | { | |
416 | struct type *values_type = check_typedef (value_type (*value_p)); | |
ad4820ab | 417 | struct gdbarch *gdbarch; |
0d5de010 DJ |
418 | |
419 | /* Some simple sanity checks. */ | |
4753d33b | 420 | if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT) |
0d5de010 DJ |
421 | error (_("Only classes can have virtual functions.")); |
422 | ||
ad4820ab | 423 | /* Determine architecture. */ |
50810684 | 424 | gdbarch = get_type_arch (values_type); |
ad4820ab | 425 | |
0d5de010 DJ |
426 | /* Cast our value to the base class which defines this virtual |
427 | function. This takes care of any necessary `this' | |
428 | adjustments. */ | |
429 | if (vfn_base != values_type) | |
430 | *value_p = value_cast (vfn_base, *value_p); | |
431 | ||
ad4820ab | 432 | return gnuv3_get_virtual_fn (gdbarch, *value_p, TYPE_FN_FIELD_TYPE (f, j), |
0d5de010 DJ |
433 | TYPE_FN_FIELD_VOFFSET (f, j)); |
434 | } | |
435 | ||
1514d34e DJ |
436 | /* Compute the offset of the baseclass which is |
437 | the INDEXth baseclass of class TYPE, | |
438 | for value at VALADDR (in host) at ADDRESS (in target). | |
439 | The result is the offset of the baseclass value relative | |
440 | to (the address of)(ARG) + OFFSET. | |
441 | ||
0963b4bd MS |
442 | -1 is returned on error. */ |
443 | ||
b9362cc7 | 444 | static int |
8af8e3bc PA |
445 | gnuv3_baseclass_offset (struct type *type, int index, |
446 | const bfd_byte *valaddr, int embedded_offset, | |
447 | CORE_ADDR address, const struct value *val) | |
1514d34e | 448 | { |
ad4820ab | 449 | struct gdbarch *gdbarch; |
ad4820ab | 450 | struct type *ptr_type; |
79d5b63a | 451 | struct value *vtable; |
2497b498 | 452 | struct value *vbase_array; |
1514d34e | 453 | long int cur_base_offset, base_offset; |
1514d34e | 454 | |
ad4820ab | 455 | /* Determine architecture. */ |
50810684 | 456 | gdbarch = get_type_arch (type); |
ad4820ab UW |
457 | ptr_type = builtin_type (gdbarch)->builtin_data_ptr; |
458 | ||
1514d34e | 459 | /* If it isn't a virtual base, this is easy. The offset is in the |
b1af9e97 TT |
460 | type definition. Likewise for Java, which doesn't really have |
461 | virtual inheritance in the C++ sense. */ | |
462 | if (!BASETYPE_VIA_VIRTUAL (type, index) || TYPE_CPLUS_REALLY_JAVA (type)) | |
1514d34e DJ |
463 | return TYPE_BASECLASS_BITPOS (type, index) / 8; |
464 | ||
465 | /* To access a virtual base, we need to use the vbase offset stored in | |
466 | our vtable. Recent GCC versions provide this information. If it isn't | |
467 | available, we could get what we needed from RTTI, or from drawing the | |
468 | complete inheritance graph based on the debug info. Neither is | |
469 | worthwhile. */ | |
470 | cur_base_offset = TYPE_BASECLASS_BITPOS (type, index) / 8; | |
ad4820ab | 471 | if (cur_base_offset >= - vtable_address_point_offset (gdbarch)) |
8a3fe4f8 | 472 | error (_("Expected a negative vbase offset (old compiler?)")); |
1514d34e | 473 | |
ad4820ab UW |
474 | cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch); |
475 | if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0) | |
8a3fe4f8 | 476 | error (_("Misaligned vbase offset.")); |
ad4820ab | 477 | cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type)); |
1514d34e | 478 | |
8af8e3bc | 479 | vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset); |
d48cc9dd | 480 | gdb_assert (vtable != NULL); |
1514d34e | 481 | vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets); |
2497b498 | 482 | base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset)); |
1514d34e DJ |
483 | return base_offset; |
484 | } | |
7ed49443 | 485 | |
0d5de010 DJ |
486 | /* Locate a virtual method in DOMAIN or its non-virtual base classes |
487 | which has virtual table index VOFFSET. The method has an associated | |
488 | "this" adjustment of ADJUSTMENT bytes. */ | |
489 | ||
2c0b251b | 490 | static const char * |
0d5de010 DJ |
491 | gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset, |
492 | LONGEST adjustment) | |
493 | { | |
494 | int i; | |
0d5de010 DJ |
495 | |
496 | /* Search this class first. */ | |
0d5de010 DJ |
497 | if (adjustment == 0) |
498 | { | |
499 | int len; | |
500 | ||
501 | len = TYPE_NFN_FIELDS (domain); | |
502 | for (i = 0; i < len; i++) | |
503 | { | |
504 | int len2, j; | |
505 | struct fn_field *f; | |
506 | ||
507 | f = TYPE_FN_FIELDLIST1 (domain, i); | |
508 | len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i); | |
509 | ||
510 | check_stub_method_group (domain, i); | |
511 | for (j = 0; j < len2; j++) | |
512 | if (TYPE_FN_FIELD_VOFFSET (f, j) == voffset) | |
513 | return TYPE_FN_FIELD_PHYSNAME (f, j); | |
514 | } | |
515 | } | |
516 | ||
517 | /* Next search non-virtual bases. If it's in a virtual base, | |
518 | we're out of luck. */ | |
519 | for (i = 0; i < TYPE_N_BASECLASSES (domain); i++) | |
520 | { | |
521 | int pos; | |
522 | struct type *basetype; | |
523 | ||
524 | if (BASETYPE_VIA_VIRTUAL (domain, i)) | |
525 | continue; | |
526 | ||
527 | pos = TYPE_BASECLASS_BITPOS (domain, i) / 8; | |
528 | basetype = TYPE_FIELD_TYPE (domain, i); | |
529 | /* Recurse with a modified adjustment. We don't need to adjust | |
530 | voffset. */ | |
531 | if (adjustment >= pos && adjustment < pos + TYPE_LENGTH (basetype)) | |
532 | return gnuv3_find_method_in (basetype, voffset, adjustment - pos); | |
533 | } | |
534 | ||
535 | return NULL; | |
536 | } | |
537 | ||
fead6908 UW |
538 | /* Decode GNU v3 method pointer. */ |
539 | ||
540 | static int | |
ad4820ab UW |
541 | gnuv3_decode_method_ptr (struct gdbarch *gdbarch, |
542 | const gdb_byte *contents, | |
fead6908 UW |
543 | CORE_ADDR *value_p, |
544 | LONGEST *adjustment_p) | |
545 | { | |
ad4820ab | 546 | struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr; |
ed09d7da | 547 | struct type *offset_type = vtable_ptrdiff_type (gdbarch); |
e17a4113 | 548 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
fead6908 UW |
549 | CORE_ADDR ptr_value; |
550 | LONGEST voffset, adjustment; | |
551 | int vbit; | |
552 | ||
553 | /* Extract the pointer to member. The first element is either a pointer | |
554 | or a vtable offset. For pointers, we need to use extract_typed_address | |
555 | to allow the back-end to convert the pointer to a GDB address -- but | |
556 | vtable offsets we must handle as integers. At this point, we do not | |
557 | yet know which case we have, so we extract the value under both | |
558 | interpretations and choose the right one later on. */ | |
559 | ptr_value = extract_typed_address (contents, funcptr_type); | |
e17a4113 UW |
560 | voffset = extract_signed_integer (contents, |
561 | TYPE_LENGTH (funcptr_type), byte_order); | |
fead6908 | 562 | contents += TYPE_LENGTH (funcptr_type); |
e17a4113 UW |
563 | adjustment = extract_signed_integer (contents, |
564 | TYPE_LENGTH (offset_type), byte_order); | |
fead6908 | 565 | |
ad4820ab | 566 | if (!gdbarch_vbit_in_delta (gdbarch)) |
fead6908 UW |
567 | { |
568 | vbit = voffset & 1; | |
569 | voffset = voffset ^ vbit; | |
570 | } | |
571 | else | |
572 | { | |
573 | vbit = adjustment & 1; | |
574 | adjustment = adjustment >> 1; | |
575 | } | |
576 | ||
577 | *value_p = vbit? voffset : ptr_value; | |
578 | *adjustment_p = adjustment; | |
579 | return vbit; | |
580 | } | |
581 | ||
0d5de010 DJ |
582 | /* GNU v3 implementation of cplus_print_method_ptr. */ |
583 | ||
584 | static void | |
585 | gnuv3_print_method_ptr (const gdb_byte *contents, | |
586 | struct type *type, | |
587 | struct ui_file *stream) | |
588 | { | |
09e2d7c7 DE |
589 | struct type *self_type = TYPE_SELF_TYPE (type); |
590 | struct gdbarch *gdbarch = get_type_arch (self_type); | |
0d5de010 DJ |
591 | CORE_ADDR ptr_value; |
592 | LONGEST adjustment; | |
0d5de010 DJ |
593 | int vbit; |
594 | ||
0d5de010 | 595 | /* Extract the pointer to member. */ |
ad4820ab | 596 | vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment); |
0d5de010 DJ |
597 | |
598 | /* Check for NULL. */ | |
599 | if (ptr_value == 0 && vbit == 0) | |
600 | { | |
601 | fprintf_filtered (stream, "NULL"); | |
602 | return; | |
603 | } | |
604 | ||
605 | /* Search for a virtual method. */ | |
606 | if (vbit) | |
607 | { | |
608 | CORE_ADDR voffset; | |
609 | const char *physname; | |
610 | ||
611 | /* It's a virtual table offset, maybe in this class. Search | |
612 | for a field with the correct vtable offset. First convert it | |
613 | to an index, as used in TYPE_FN_FIELD_VOFFSET. */ | |
ed09d7da | 614 | voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch)); |
0d5de010 | 615 | |
09e2d7c7 | 616 | physname = gnuv3_find_method_in (self_type, voffset, adjustment); |
0d5de010 DJ |
617 | |
618 | /* If we found a method, print that. We don't bother to disambiguate | |
619 | possible paths to the method based on the adjustment. */ | |
620 | if (physname) | |
621 | { | |
8de20a37 TT |
622 | char *demangled_name = gdb_demangle (physname, |
623 | DMGL_ANSI | DMGL_PARAMS); | |
d8734c88 | 624 | |
94af9270 KS |
625 | fprintf_filtered (stream, "&virtual "); |
626 | if (demangled_name == NULL) | |
627 | fputs_filtered (physname, stream); | |
628 | else | |
0d5de010 | 629 | { |
0d5de010 DJ |
630 | fputs_filtered (demangled_name, stream); |
631 | xfree (demangled_name); | |
0d5de010 | 632 | } |
94af9270 | 633 | return; |
0d5de010 DJ |
634 | } |
635 | } | |
94af9270 KS |
636 | else if (ptr_value != 0) |
637 | { | |
638 | /* Found a non-virtual function: print out the type. */ | |
639 | fputs_filtered ("(", stream); | |
79d43c61 | 640 | c_print_type (type, "", stream, -1, 0, &type_print_raw_options); |
94af9270 KS |
641 | fputs_filtered (") ", stream); |
642 | } | |
0d5de010 DJ |
643 | |
644 | /* We didn't find it; print the raw data. */ | |
645 | if (vbit) | |
646 | { | |
647 | fprintf_filtered (stream, "&virtual table offset "); | |
648 | print_longest (stream, 'd', 1, ptr_value); | |
649 | } | |
650 | else | |
edf0c1b7 TT |
651 | { |
652 | struct value_print_options opts; | |
653 | ||
654 | get_user_print_options (&opts); | |
655 | print_address_demangle (&opts, gdbarch, ptr_value, stream, demangle); | |
656 | } | |
0d5de010 DJ |
657 | |
658 | if (adjustment) | |
659 | { | |
660 | fprintf_filtered (stream, ", this adjustment "); | |
661 | print_longest (stream, 'd', 1, adjustment); | |
662 | } | |
663 | } | |
664 | ||
665 | /* GNU v3 implementation of cplus_method_ptr_size. */ | |
666 | ||
667 | static int | |
ad4820ab | 668 | gnuv3_method_ptr_size (struct type *type) |
0d5de010 | 669 | { |
561d3825 | 670 | struct gdbarch *gdbarch = get_type_arch (type); |
d8734c88 | 671 | |
ad4820ab | 672 | return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr); |
0d5de010 DJ |
673 | } |
674 | ||
675 | /* GNU v3 implementation of cplus_make_method_ptr. */ | |
676 | ||
677 | static void | |
ad4820ab UW |
678 | gnuv3_make_method_ptr (struct type *type, gdb_byte *contents, |
679 | CORE_ADDR value, int is_virtual) | |
0d5de010 | 680 | { |
561d3825 | 681 | struct gdbarch *gdbarch = get_type_arch (type); |
ad4820ab | 682 | int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr); |
e17a4113 | 683 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
0d5de010 DJ |
684 | |
685 | /* FIXME drow/2006-12-24: The adjustment of "this" is currently | |
686 | always zero, since the method pointer is of the correct type. | |
687 | But if the method pointer came from a base class, this is | |
688 | incorrect - it should be the offset to the base. The best | |
689 | fix might be to create the pointer to member pointing at the | |
690 | base class and cast it to the derived class, but that requires | |
691 | support for adjusting pointers to members when casting them - | |
692 | not currently supported by GDB. */ | |
693 | ||
ad4820ab | 694 | if (!gdbarch_vbit_in_delta (gdbarch)) |
0d5de010 | 695 | { |
e17a4113 UW |
696 | store_unsigned_integer (contents, size, byte_order, value | is_virtual); |
697 | store_unsigned_integer (contents + size, size, byte_order, 0); | |
0d5de010 DJ |
698 | } |
699 | else | |
700 | { | |
e17a4113 UW |
701 | store_unsigned_integer (contents, size, byte_order, value); |
702 | store_unsigned_integer (contents + size, size, byte_order, is_virtual); | |
0d5de010 DJ |
703 | } |
704 | } | |
705 | ||
706 | /* GNU v3 implementation of cplus_method_ptr_to_value. */ | |
707 | ||
708 | static struct value * | |
709 | gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr) | |
710 | { | |
ad4820ab | 711 | struct gdbarch *gdbarch; |
0d5de010 DJ |
712 | const gdb_byte *contents = value_contents (method_ptr); |
713 | CORE_ADDR ptr_value; | |
09e2d7c7 | 714 | struct type *self_type, *final_type, *method_type; |
0d5de010 | 715 | LONGEST adjustment; |
0d5de010 DJ |
716 | int vbit; |
717 | ||
09e2d7c7 DE |
718 | self_type = TYPE_SELF_TYPE (check_typedef (value_type (method_ptr))); |
719 | final_type = lookup_pointer_type (self_type); | |
0d5de010 DJ |
720 | |
721 | method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr))); | |
722 | ||
fead6908 | 723 | /* Extract the pointer to member. */ |
09e2d7c7 | 724 | gdbarch = get_type_arch (self_type); |
ad4820ab | 725 | vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment); |
0d5de010 DJ |
726 | |
727 | /* First convert THIS to match the containing type of the pointer to | |
728 | member. This cast may adjust the value of THIS. */ | |
729 | *this_p = value_cast (final_type, *this_p); | |
730 | ||
731 | /* Then apply whatever adjustment is necessary. This creates a somewhat | |
732 | strange pointer: it claims to have type FINAL_TYPE, but in fact it | |
733 | might not be a valid FINAL_TYPE. For instance, it might be a | |
734 | base class of FINAL_TYPE. And if it's not the primary base class, | |
735 | then printing it out as a FINAL_TYPE object would produce some pretty | |
736 | garbage. | |
737 | ||
738 | But we don't really know the type of the first argument in | |
739 | METHOD_TYPE either, which is why this happens. We can't | |
740 | dereference this later as a FINAL_TYPE, but once we arrive in the | |
741 | called method we'll have debugging information for the type of | |
742 | "this" - and that'll match the value we produce here. | |
743 | ||
744 | You can provoke this case by casting a Base::* to a Derived::*, for | |
745 | instance. */ | |
ad4820ab | 746 | *this_p = value_cast (builtin_type (gdbarch)->builtin_data_ptr, *this_p); |
2497b498 | 747 | *this_p = value_ptradd (*this_p, adjustment); |
0d5de010 DJ |
748 | *this_p = value_cast (final_type, *this_p); |
749 | ||
750 | if (vbit) | |
751 | { | |
ad4820ab | 752 | LONGEST voffset; |
d8734c88 | 753 | |
ed09d7da | 754 | voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch)); |
ad4820ab UW |
755 | return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p), |
756 | method_type, voffset); | |
0d5de010 DJ |
757 | } |
758 | else | |
759 | return value_from_pointer (lookup_pointer_type (method_type), ptr_value); | |
760 | } | |
761 | ||
c4aeac85 TT |
762 | /* Objects of this type are stored in a hash table and a vector when |
763 | printing the vtables for a class. */ | |
764 | ||
765 | struct value_and_voffset | |
766 | { | |
767 | /* The value representing the object. */ | |
768 | struct value *value; | |
769 | ||
770 | /* The maximum vtable offset we've found for any object at this | |
771 | offset in the outermost object. */ | |
772 | int max_voffset; | |
773 | }; | |
774 | ||
775 | typedef struct value_and_voffset *value_and_voffset_p; | |
776 | DEF_VEC_P (value_and_voffset_p); | |
777 | ||
778 | /* Hash function for value_and_voffset. */ | |
779 | ||
780 | static hashval_t | |
781 | hash_value_and_voffset (const void *p) | |
782 | { | |
9a3c8263 | 783 | const struct value_and_voffset *o = (const struct value_and_voffset *) p; |
c4aeac85 TT |
784 | |
785 | return value_address (o->value) + value_embedded_offset (o->value); | |
786 | } | |
787 | ||
788 | /* Equality function for value_and_voffset. */ | |
789 | ||
790 | static int | |
791 | eq_value_and_voffset (const void *a, const void *b) | |
792 | { | |
9a3c8263 SM |
793 | const struct value_and_voffset *ova = (const struct value_and_voffset *) a; |
794 | const struct value_and_voffset *ovb = (const struct value_and_voffset *) b; | |
c4aeac85 TT |
795 | |
796 | return (value_address (ova->value) + value_embedded_offset (ova->value) | |
797 | == value_address (ovb->value) + value_embedded_offset (ovb->value)); | |
798 | } | |
799 | ||
800 | /* qsort comparison function for value_and_voffset. */ | |
801 | ||
802 | static int | |
803 | compare_value_and_voffset (const void *a, const void *b) | |
804 | { | |
9a3c8263 SM |
805 | const struct value_and_voffset * const *ova |
806 | = (const struct value_and_voffset * const *) a; | |
c4aeac85 TT |
807 | CORE_ADDR addra = (value_address ((*ova)->value) |
808 | + value_embedded_offset ((*ova)->value)); | |
9a3c8263 SM |
809 | const struct value_and_voffset * const *ovb |
810 | = (const struct value_and_voffset * const *) b; | |
c4aeac85 TT |
811 | CORE_ADDR addrb = (value_address ((*ovb)->value) |
812 | + value_embedded_offset ((*ovb)->value)); | |
813 | ||
814 | if (addra < addrb) | |
815 | return -1; | |
816 | if (addra > addrb) | |
817 | return 1; | |
818 | return 0; | |
819 | } | |
820 | ||
821 | /* A helper function used when printing vtables. This determines the | |
822 | key (most derived) sub-object at each address and also computes the | |
823 | maximum vtable offset seen for the corresponding vtable. Updates | |
824 | OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if | |
825 | needed. VALUE is the object to examine. */ | |
826 | ||
827 | static void | |
828 | compute_vtable_size (htab_t offset_hash, | |
829 | VEC (value_and_voffset_p) **offset_vec, | |
830 | struct value *value) | |
831 | { | |
832 | int i; | |
833 | struct type *type = check_typedef (value_type (value)); | |
834 | void **slot; | |
835 | struct value_and_voffset search_vo, *current_vo; | |
c4aeac85 | 836 | |
5f4ce105 DE |
837 | gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT); |
838 | ||
c4aeac85 TT |
839 | /* If the object is not dynamic, then we are done; as it cannot have |
840 | dynamic base types either. */ | |
841 | if (!gnuv3_dynamic_class (type)) | |
842 | return; | |
843 | ||
844 | /* Update the hash and the vec, if needed. */ | |
845 | search_vo.value = value; | |
846 | slot = htab_find_slot (offset_hash, &search_vo, INSERT); | |
847 | if (*slot) | |
9a3c8263 | 848 | current_vo = (struct value_and_voffset *) *slot; |
c4aeac85 TT |
849 | else |
850 | { | |
851 | current_vo = XNEW (struct value_and_voffset); | |
852 | current_vo->value = value; | |
853 | current_vo->max_voffset = -1; | |
854 | *slot = current_vo; | |
855 | VEC_safe_push (value_and_voffset_p, *offset_vec, current_vo); | |
856 | } | |
857 | ||
858 | /* Update the value_and_voffset object with the highest vtable | |
859 | offset from this class. */ | |
860 | for (i = 0; i < TYPE_NFN_FIELDS (type); ++i) | |
861 | { | |
862 | int j; | |
863 | struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, i); | |
864 | ||
865 | for (j = 0; j < TYPE_FN_FIELDLIST_LENGTH (type, i); ++j) | |
866 | { | |
867 | if (TYPE_FN_FIELD_VIRTUAL_P (fn, j)) | |
868 | { | |
869 | int voffset = TYPE_FN_FIELD_VOFFSET (fn, j); | |
870 | ||
871 | if (voffset > current_vo->max_voffset) | |
872 | current_vo->max_voffset = voffset; | |
873 | } | |
874 | } | |
875 | } | |
876 | ||
877 | /* Recurse into base classes. */ | |
878 | for (i = 0; i < TYPE_N_BASECLASSES (type); ++i) | |
879 | compute_vtable_size (offset_hash, offset_vec, value_field (value, i)); | |
880 | } | |
881 | ||
882 | /* Helper for gnuv3_print_vtable that prints a single vtable. */ | |
883 | ||
884 | static void | |
885 | print_one_vtable (struct gdbarch *gdbarch, struct value *value, | |
886 | int max_voffset, | |
887 | struct value_print_options *opts) | |
888 | { | |
889 | int i; | |
890 | struct type *type = check_typedef (value_type (value)); | |
891 | struct value *vtable; | |
892 | CORE_ADDR vt_addr; | |
893 | ||
894 | vtable = gnuv3_get_vtable (gdbarch, type, | |
895 | value_address (value) | |
896 | + value_embedded_offset (value)); | |
897 | vt_addr = value_address (value_field (vtable, | |
898 | vtable_field_virtual_functions)); | |
899 | ||
900 | printf_filtered (_("vtable for '%s' @ %s (subobject @ %s):\n"), | |
901 | TYPE_SAFE_NAME (type), | |
902 | paddress (gdbarch, vt_addr), | |
903 | paddress (gdbarch, (value_address (value) | |
904 | + value_embedded_offset (value)))); | |
905 | ||
906 | for (i = 0; i <= max_voffset; ++i) | |
907 | { | |
cafe75b0 JK |
908 | /* Initialize it just to avoid a GCC false warning. */ |
909 | CORE_ADDR addr = 0; | |
492d29ea | 910 | int got_error = 0; |
c4aeac85 | 911 | struct value *vfn; |
c4aeac85 TT |
912 | |
913 | printf_filtered ("[%d]: ", i); | |
914 | ||
915 | vfn = value_subscript (value_field (vtable, | |
916 | vtable_field_virtual_functions), | |
917 | i); | |
918 | ||
919 | if (gdbarch_vtable_function_descriptors (gdbarch)) | |
920 | vfn = value_addr (vfn); | |
921 | ||
492d29ea | 922 | TRY |
c4aeac85 TT |
923 | { |
924 | addr = value_as_address (vfn); | |
925 | } | |
492d29ea PA |
926 | CATCH (ex, RETURN_MASK_ERROR) |
927 | { | |
928 | printf_filtered (_("<error: %s>"), ex.message); | |
929 | got_error = 1; | |
930 | } | |
931 | END_CATCH | |
932 | ||
933 | if (!got_error) | |
edf0c1b7 | 934 | print_function_pointer_address (opts, gdbarch, addr, gdb_stdout); |
c4aeac85 TT |
935 | printf_filtered ("\n"); |
936 | } | |
937 | } | |
938 | ||
939 | /* Implementation of the print_vtable method. */ | |
940 | ||
941 | static void | |
942 | gnuv3_print_vtable (struct value *value) | |
943 | { | |
944 | struct gdbarch *gdbarch; | |
945 | struct type *type; | |
946 | struct value *vtable; | |
947 | struct value_print_options opts; | |
948 | htab_t offset_hash; | |
949 | struct cleanup *cleanup; | |
5ff5c7b4 | 950 | VEC (value_and_voffset_p) *result_vec = NULL; |
c4aeac85 TT |
951 | struct value_and_voffset *iter; |
952 | int i, count; | |
953 | ||
954 | value = coerce_ref (value); | |
955 | type = check_typedef (value_type (value)); | |
956 | if (TYPE_CODE (type) == TYPE_CODE_PTR) | |
957 | { | |
958 | value = value_ind (value); | |
959 | type = check_typedef (value_type (value)); | |
960 | } | |
961 | ||
962 | get_user_print_options (&opts); | |
963 | ||
964 | /* Respect 'set print object'. */ | |
965 | if (opts.objectprint) | |
966 | { | |
967 | value = value_full_object (value, NULL, 0, 0, 0); | |
968 | type = check_typedef (value_type (value)); | |
969 | } | |
970 | ||
971 | gdbarch = get_type_arch (type); | |
5f4ce105 DE |
972 | |
973 | vtable = NULL; | |
974 | if (TYPE_CODE (type) == TYPE_CODE_STRUCT) | |
975 | vtable = gnuv3_get_vtable (gdbarch, type, | |
976 | value_as_address (value_addr (value))); | |
c4aeac85 TT |
977 | |
978 | if (!vtable) | |
979 | { | |
980 | printf_filtered (_("This object does not have a virtual function table\n")); | |
981 | return; | |
982 | } | |
983 | ||
984 | offset_hash = htab_create_alloc (1, hash_value_and_voffset, | |
985 | eq_value_and_voffset, | |
986 | xfree, xcalloc, xfree); | |
987 | cleanup = make_cleanup_htab_delete (offset_hash); | |
988 | make_cleanup (VEC_cleanup (value_and_voffset_p), &result_vec); | |
989 | ||
990 | compute_vtable_size (offset_hash, &result_vec, value); | |
991 | ||
992 | qsort (VEC_address (value_and_voffset_p, result_vec), | |
993 | VEC_length (value_and_voffset_p, result_vec), | |
994 | sizeof (value_and_voffset_p), | |
995 | compare_value_and_voffset); | |
996 | ||
997 | count = 0; | |
998 | for (i = 0; VEC_iterate (value_and_voffset_p, result_vec, i, iter); ++i) | |
999 | { | |
1000 | if (iter->max_voffset >= 0) | |
1001 | { | |
1002 | if (count > 0) | |
1003 | printf_filtered ("\n"); | |
1004 | print_one_vtable (gdbarch, iter->value, iter->max_voffset, &opts); | |
1005 | ++count; | |
1006 | } | |
1007 | } | |
1008 | ||
1009 | do_cleanups (cleanup); | |
1010 | } | |
1011 | ||
6e72ca20 TT |
1012 | /* Return a GDB type representing `struct std::type_info', laid out |
1013 | appropriately for ARCH. | |
1014 | ||
1015 | We use this function as the gdbarch per-architecture data | |
1016 | initialization function. */ | |
1017 | ||
1018 | static void * | |
1019 | build_std_type_info_type (struct gdbarch *arch) | |
1020 | { | |
1021 | struct type *t; | |
1022 | struct field *field_list, *field; | |
1023 | int offset; | |
1024 | struct type *void_ptr_type | |
1025 | = builtin_type (arch)->builtin_data_ptr; | |
1026 | struct type *char_type | |
1027 | = builtin_type (arch)->builtin_char; | |
1028 | struct type *char_ptr_type | |
1029 | = make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL); | |
1030 | ||
8d749320 | 1031 | field_list = XCNEWVEC (struct field, 2); |
6e72ca20 TT |
1032 | field = &field_list[0]; |
1033 | offset = 0; | |
1034 | ||
1035 | /* The vtable. */ | |
1036 | FIELD_NAME (*field) = "_vptr.type_info"; | |
1037 | FIELD_TYPE (*field) = void_ptr_type; | |
1038 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); | |
1039 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); | |
1040 | field++; | |
1041 | ||
1042 | /* The name. */ | |
1043 | FIELD_NAME (*field) = "__name"; | |
1044 | FIELD_TYPE (*field) = char_ptr_type; | |
1045 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); | |
1046 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); | |
1047 | field++; | |
1048 | ||
1049 | gdb_assert (field == (field_list + 2)); | |
1050 | ||
1051 | t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL); | |
1052 | TYPE_NFIELDS (t) = field - field_list; | |
1053 | TYPE_FIELDS (t) = field_list; | |
1054 | TYPE_TAG_NAME (t) = "gdb_gnu_v3_type_info"; | |
1055 | INIT_CPLUS_SPECIFIC (t); | |
1056 | ||
1057 | return t; | |
1058 | } | |
1059 | ||
1060 | /* Implement the 'get_typeid_type' method. */ | |
1061 | ||
1062 | static struct type * | |
1063 | gnuv3_get_typeid_type (struct gdbarch *gdbarch) | |
1064 | { | |
1065 | struct symbol *typeinfo; | |
1066 | struct type *typeinfo_type; | |
1067 | ||
d12307c1 PMR |
1068 | typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN, |
1069 | NULL).symbol; | |
6e72ca20 | 1070 | if (typeinfo == NULL) |
9a3c8263 SM |
1071 | typeinfo_type |
1072 | = (struct type *) gdbarch_data (gdbarch, std_type_info_gdbarch_data); | |
6e72ca20 TT |
1073 | else |
1074 | typeinfo_type = SYMBOL_TYPE (typeinfo); | |
1075 | ||
1076 | return typeinfo_type; | |
1077 | } | |
1078 | ||
1079 | /* Implement the 'get_typeid' method. */ | |
1080 | ||
1081 | static struct value * | |
1082 | gnuv3_get_typeid (struct value *value) | |
1083 | { | |
1084 | struct type *typeinfo_type; | |
1085 | struct type *type; | |
1086 | struct gdbarch *gdbarch; | |
1087 | struct cleanup *cleanup; | |
1088 | struct value *result; | |
fe978cb0 | 1089 | char *type_name, *canonical; |
6e72ca20 TT |
1090 | |
1091 | /* We have to handle values a bit trickily here, to allow this code | |
1092 | to work properly with non_lvalue values that are really just | |
1093 | disguised types. */ | |
1094 | if (value_lval_const (value) == lval_memory) | |
1095 | value = coerce_ref (value); | |
1096 | ||
1097 | type = check_typedef (value_type (value)); | |
1098 | ||
1099 | /* In the non_lvalue case, a reference might have slipped through | |
1100 | here. */ | |
1101 | if (TYPE_CODE (type) == TYPE_CODE_REF) | |
1102 | type = check_typedef (TYPE_TARGET_TYPE (type)); | |
1103 | ||
1104 | /* Ignore top-level cv-qualifiers. */ | |
1105 | type = make_cv_type (0, 0, type, NULL); | |
1106 | gdbarch = get_type_arch (type); | |
1107 | ||
fe978cb0 PA |
1108 | type_name = type_to_string (type); |
1109 | if (type_name == NULL) | |
6e72ca20 | 1110 | error (_("cannot find typeinfo for unnamed type")); |
fe978cb0 | 1111 | cleanup = make_cleanup (xfree, type_name); |
6e72ca20 TT |
1112 | |
1113 | /* We need to canonicalize the type name here, because we do lookups | |
1114 | using the demangled name, and so we must match the format it | |
1115 | uses. E.g., GDB tends to use "const char *" as a type name, but | |
1116 | the demangler uses "char const *". */ | |
fe978cb0 | 1117 | canonical = cp_canonicalize_string (type_name); |
6e72ca20 TT |
1118 | if (canonical != NULL) |
1119 | { | |
1120 | make_cleanup (xfree, canonical); | |
fe978cb0 | 1121 | type_name = canonical; |
6e72ca20 TT |
1122 | } |
1123 | ||
1124 | typeinfo_type = gnuv3_get_typeid_type (gdbarch); | |
1125 | ||
1126 | /* We check for lval_memory because in the "typeid (type-id)" case, | |
1127 | the type is passed via a not_lval value object. */ | |
4753d33b | 1128 | if (TYPE_CODE (type) == TYPE_CODE_STRUCT |
6e72ca20 TT |
1129 | && value_lval_const (value) == lval_memory |
1130 | && gnuv3_dynamic_class (type)) | |
1131 | { | |
1132 | struct value *vtable, *typeinfo_value; | |
1133 | CORE_ADDR address = value_address (value) + value_embedded_offset (value); | |
1134 | ||
1135 | vtable = gnuv3_get_vtable (gdbarch, type, address); | |
1136 | if (vtable == NULL) | |
fe978cb0 | 1137 | error (_("cannot find typeinfo for object of type '%s'"), type_name); |
6e72ca20 TT |
1138 | typeinfo_value = value_field (vtable, vtable_field_type_info); |
1139 | result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL), | |
1140 | typeinfo_value)); | |
1141 | } | |
1142 | else | |
1143 | { | |
1144 | char *sym_name; | |
3b7344d5 | 1145 | struct bound_minimal_symbol minsym; |
6e72ca20 | 1146 | |
fe978cb0 | 1147 | sym_name = concat ("typeinfo for ", type_name, (char *) NULL); |
6e72ca20 TT |
1148 | make_cleanup (xfree, sym_name); |
1149 | minsym = lookup_minimal_symbol (sym_name, NULL, NULL); | |
1150 | ||
3b7344d5 | 1151 | if (minsym.minsym == NULL) |
fe978cb0 | 1152 | error (_("could not find typeinfo symbol for '%s'"), type_name); |
6e72ca20 | 1153 | |
77e371c0 | 1154 | result = value_at_lazy (typeinfo_type, BMSYMBOL_VALUE_ADDRESS (minsym)); |
6e72ca20 TT |
1155 | } |
1156 | ||
1157 | do_cleanups (cleanup); | |
1158 | return result; | |
1159 | } | |
1160 | ||
cc16e6c9 | 1161 | /* Implement the 'get_typename_from_type_info' method. */ |
72f1fe8a TT |
1162 | |
1163 | static char * | |
1164 | gnuv3_get_typename_from_type_info (struct value *type_info_ptr) | |
1165 | { | |
1166 | struct gdbarch *gdbarch = get_type_arch (value_type (type_info_ptr)); | |
1167 | struct bound_minimal_symbol typeinfo_sym; | |
1168 | CORE_ADDR addr; | |
1169 | const char *symname; | |
1170 | const char *class_name; | |
1171 | const char *atsign; | |
1172 | ||
1173 | addr = value_as_address (type_info_ptr); | |
1174 | typeinfo_sym = lookup_minimal_symbol_by_pc (addr); | |
1175 | if (typeinfo_sym.minsym == NULL) | |
1176 | error (_("could not find minimal symbol for typeinfo address %s"), | |
1177 | paddress (gdbarch, addr)); | |
1178 | ||
1179 | #define TYPEINFO_PREFIX "typeinfo for " | |
1180 | #define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1) | |
efd66ac6 | 1181 | symname = MSYMBOL_DEMANGLED_NAME (typeinfo_sym.minsym); |
72f1fe8a TT |
1182 | if (symname == NULL || strncmp (symname, TYPEINFO_PREFIX, |
1183 | TYPEINFO_PREFIX_LEN)) | |
1184 | error (_("typeinfo symbol '%s' has unexpected name"), | |
efd66ac6 | 1185 | MSYMBOL_LINKAGE_NAME (typeinfo_sym.minsym)); |
72f1fe8a TT |
1186 | class_name = symname + TYPEINFO_PREFIX_LEN; |
1187 | ||
1188 | /* Strip off @plt and version suffixes. */ | |
1189 | atsign = strchr (class_name, '@'); | |
1190 | if (atsign != NULL) | |
1191 | return savestring (class_name, atsign - class_name); | |
1192 | return xstrdup (class_name); | |
1193 | } | |
1194 | ||
1195 | /* Implement the 'get_type_from_type_info' method. */ | |
1196 | ||
1197 | static struct type * | |
1198 | gnuv3_get_type_from_type_info (struct value *type_info_ptr) | |
1199 | { | |
fe978cb0 | 1200 | char *type_name; |
72f1fe8a TT |
1201 | struct cleanup *cleanup; |
1202 | struct value *type_val; | |
1203 | struct expression *expr; | |
1204 | struct type *result; | |
1205 | ||
fe978cb0 PA |
1206 | type_name = gnuv3_get_typename_from_type_info (type_info_ptr); |
1207 | cleanup = make_cleanup (xfree, type_name); | |
72f1fe8a TT |
1208 | |
1209 | /* We have to parse the type name, since in general there is not a | |
1210 | symbol for a type. This is somewhat bogus since there may be a | |
1211 | mis-parse. Another approach might be to re-use the demangler's | |
1212 | internal form to reconstruct the type somehow. */ | |
1213 | ||
fe978cb0 | 1214 | expr = parse_expression (type_name); |
72f1fe8a TT |
1215 | make_cleanup (xfree, expr); |
1216 | ||
1217 | type_val = evaluate_type (expr); | |
1218 | result = value_type (type_val); | |
1219 | ||
1220 | do_cleanups (cleanup); | |
1221 | return result; | |
1222 | } | |
1223 | ||
b18be20d DJ |
1224 | /* Determine if we are currently in a C++ thunk. If so, get the address |
1225 | of the routine we are thunking to and continue to there instead. */ | |
1226 | ||
1227 | static CORE_ADDR | |
52f729a7 | 1228 | gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc) |
b18be20d | 1229 | { |
a513d1e8 | 1230 | CORE_ADDR real_stop_pc, method_stop_pc, func_addr; |
9970f04b | 1231 | struct gdbarch *gdbarch = get_frame_arch (frame); |
3b7344d5 | 1232 | struct bound_minimal_symbol thunk_sym, fn_sym; |
b18be20d | 1233 | struct obj_section *section; |
0d5cff50 | 1234 | const char *thunk_name, *fn_name; |
b18be20d | 1235 | |
9970f04b | 1236 | real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
b18be20d DJ |
1237 | if (real_stop_pc == 0) |
1238 | real_stop_pc = stop_pc; | |
1239 | ||
1240 | /* Find the linker symbol for this potential thunk. */ | |
3b7344d5 | 1241 | thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc); |
b18be20d | 1242 | section = find_pc_section (real_stop_pc); |
3b7344d5 | 1243 | if (thunk_sym.minsym == NULL || section == NULL) |
b18be20d DJ |
1244 | return 0; |
1245 | ||
1246 | /* The symbol's demangled name should be something like "virtual | |
1247 | thunk to FUNCTION", where FUNCTION is the name of the function | |
1248 | being thunked to. */ | |
3b7344d5 | 1249 | thunk_name = MSYMBOL_DEMANGLED_NAME (thunk_sym.minsym); |
b18be20d DJ |
1250 | if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL) |
1251 | return 0; | |
1252 | ||
1253 | fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to "); | |
1254 | fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile); | |
3b7344d5 | 1255 | if (fn_sym.minsym == NULL) |
b18be20d DJ |
1256 | return 0; |
1257 | ||
77e371c0 | 1258 | method_stop_pc = BMSYMBOL_VALUE_ADDRESS (fn_sym); |
a513d1e8 LM |
1259 | |
1260 | /* Some targets have minimal symbols pointing to function descriptors | |
1261 | (powerpc 64 for example). Make sure to retrieve the address | |
1262 | of the real function from the function descriptor before passing on | |
1263 | the address to other layers of GDB. */ | |
1264 | func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, method_stop_pc, | |
1265 | ¤t_target); | |
1266 | if (func_addr != 0) | |
1267 | method_stop_pc = func_addr; | |
1268 | ||
e76f05fa | 1269 | real_stop_pc = gdbarch_skip_trampoline_code |
9970f04b | 1270 | (gdbarch, frame, method_stop_pc); |
b18be20d DJ |
1271 | if (real_stop_pc == 0) |
1272 | real_stop_pc = method_stop_pc; | |
1273 | ||
1274 | return real_stop_pc; | |
1275 | } | |
1276 | ||
41f1b697 DJ |
1277 | /* Return nonzero if a type should be passed by reference. |
1278 | ||
1279 | The rule in the v3 ABI document comes from section 3.1.1. If the | |
1280 | type has a non-trivial copy constructor or destructor, then the | |
1281 | caller must make a copy (by calling the copy constructor if there | |
1282 | is one or perform the copy itself otherwise), pass the address of | |
1283 | the copy, and then destroy the temporary (if necessary). | |
1284 | ||
1285 | For return values with non-trivial copy constructors or | |
1286 | destructors, space will be allocated in the caller, and a pointer | |
1287 | will be passed as the first argument (preceding "this"). | |
1288 | ||
1289 | We don't have a bulletproof mechanism for determining whether a | |
1290 | constructor or destructor is trivial. For GCC and DWARF2 debug | |
1291 | information, we can check the artificial flag. | |
1292 | ||
1293 | We don't do anything with the constructors or destructors, | |
1294 | but we have to get the argument passing right anyway. */ | |
1295 | static int | |
1296 | gnuv3_pass_by_reference (struct type *type) | |
1297 | { | |
1298 | int fieldnum, fieldelem; | |
1299 | ||
f168693b | 1300 | type = check_typedef (type); |
41f1b697 DJ |
1301 | |
1302 | /* We're only interested in things that can have methods. */ | |
1303 | if (TYPE_CODE (type) != TYPE_CODE_STRUCT | |
41f1b697 DJ |
1304 | && TYPE_CODE (type) != TYPE_CODE_UNION) |
1305 | return 0; | |
1306 | ||
ebb8ece2 SC |
1307 | /* A dynamic class has a non-trivial copy constructor. |
1308 | See c++98 section 12.8 Copying class objects [class.copy]. */ | |
1309 | if (gnuv3_dynamic_class (type)) | |
1310 | return 1; | |
1311 | ||
41f1b697 DJ |
1312 | for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++) |
1313 | for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum); | |
1314 | fieldelem++) | |
1315 | { | |
1316 | struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum); | |
0d5cff50 | 1317 | const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum); |
41f1b697 DJ |
1318 | struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem); |
1319 | ||
1320 | /* If this function is marked as artificial, it is compiler-generated, | |
1321 | and we assume it is trivial. */ | |
1322 | if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem)) | |
1323 | continue; | |
1324 | ||
1325 | /* If we've found a destructor, we must pass this by reference. */ | |
1326 | if (name[0] == '~') | |
1327 | return 1; | |
1328 | ||
1329 | /* If the mangled name of this method doesn't indicate that it | |
1330 | is a constructor, we're not interested. | |
1331 | ||
1332 | FIXME drow/2007-09-23: We could do this using the name of | |
1333 | the method and the name of the class instead of dealing | |
1334 | with the mangled name. We don't have a convenient function | |
1335 | to strip off both leading scope qualifiers and trailing | |
1336 | template arguments yet. */ | |
7d27a96d TT |
1337 | if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem)) |
1338 | && !TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem)) | |
41f1b697 DJ |
1339 | continue; |
1340 | ||
1341 | /* If this method takes two arguments, and the second argument is | |
1342 | a reference to this class, then it is a copy constructor. */ | |
82c48ac7 SC |
1343 | if (TYPE_NFIELDS (fieldtype) == 2) |
1344 | { | |
1345 | struct type *arg_type = TYPE_FIELD_TYPE (fieldtype, 1); | |
82c48ac7 | 1346 | |
3433cfa5 SC |
1347 | if (TYPE_CODE (arg_type) == TYPE_CODE_REF) |
1348 | { | |
1349 | struct type *arg_target_type; | |
82c48ac7 | 1350 | |
3433cfa5 SC |
1351 | arg_target_type = check_typedef (TYPE_TARGET_TYPE (arg_type)); |
1352 | if (class_types_same_p (arg_target_type, type)) | |
1353 | return 1; | |
1354 | } | |
82c48ac7 | 1355 | } |
41f1b697 DJ |
1356 | } |
1357 | ||
1358 | /* Even if all the constructors and destructors were artificial, one | |
1359 | of them may have invoked a non-artificial constructor or | |
1360 | destructor in a base class. If any base class needs to be passed | |
1361 | by reference, so does this class. Similarly for members, which | |
1362 | are constructed whenever this class is. We do not need to worry | |
1363 | about recursive loops here, since we are only looking at members | |
bceffbf3 | 1364 | of complete class type. Also ignore any static members. */ |
41f1b697 | 1365 | for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++) |
bceffbf3 JK |
1366 | if (! field_is_static (&TYPE_FIELD (type, fieldnum)) |
1367 | && gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum))) | |
41f1b697 DJ |
1368 | return 1; |
1369 | ||
1370 | return 0; | |
1371 | } | |
1372 | ||
7ed49443 JB |
1373 | static void |
1374 | init_gnuv3_ops (void) | |
1375 | { | |
0963b4bd MS |
1376 | vtable_type_gdbarch_data |
1377 | = gdbarch_data_register_post_init (build_gdb_vtable_type); | |
6e72ca20 TT |
1378 | std_type_info_gdbarch_data |
1379 | = gdbarch_data_register_post_init (build_std_type_info_type); | |
7ed49443 JB |
1380 | |
1381 | gnu_v3_abi_ops.shortname = "gnu-v3"; | |
1382 | gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI"; | |
1383 | gnu_v3_abi_ops.doc = "G++ Version 3 ABI"; | |
358777b0 EZ |
1384 | gnu_v3_abi_ops.is_destructor_name = |
1385 | (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor; | |
1386 | gnu_v3_abi_ops.is_constructor_name = | |
1387 | (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor; | |
7ed49443 JB |
1388 | gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name; |
1389 | gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name; | |
1390 | gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type; | |
1391 | gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field; | |
1514d34e | 1392 | gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset; |
0d5de010 DJ |
1393 | gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr; |
1394 | gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size; | |
1395 | gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr; | |
1396 | gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value; | |
c4aeac85 | 1397 | gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable; |
6e72ca20 TT |
1398 | gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid; |
1399 | gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type; | |
72f1fe8a | 1400 | gnu_v3_abi_ops.get_type_from_type_info = gnuv3_get_type_from_type_info; |
cc16e6c9 TT |
1401 | gnu_v3_abi_ops.get_typename_from_type_info |
1402 | = gnuv3_get_typename_from_type_info; | |
b18be20d | 1403 | gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline; |
41f1b697 | 1404 | gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference; |
7ed49443 JB |
1405 | } |
1406 | ||
b9362cc7 | 1407 | extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */ |
7ed49443 JB |
1408 | |
1409 | void | |
1410 | _initialize_gnu_v3_abi (void) | |
1411 | { | |
1412 | init_gnuv3_ops (); | |
1413 | ||
fe1f4a5e | 1414 | register_cp_abi (&gnu_v3_abi_ops); |
1605ef26 | 1415 | set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname); |
7ed49443 | 1416 | } |