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7ed49443 JB |
1 | /* Abstraction of GNU v3 abi. |
2 | Contributed by Jim Blandy <jimb@redhat.com> | |
451fbdda | 3 | |
28e7fd62 | 4 | Copyright (C) 2001-2013 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" |
c4aeac85 | 29 | #include "exceptions.h" |
79d43c61 | 30 | #include "typeprint.h" |
0d5de010 | 31 | |
3d499020 | 32 | #include "gdb_assert.h" |
5f8a3188 | 33 | #include "gdb_string.h" |
7ed49443 | 34 | |
b27b8843 | 35 | static struct cp_abi_ops gnu_v3_abi_ops; |
7ed49443 JB |
36 | |
37 | static int | |
38 | gnuv3_is_vtable_name (const char *name) | |
39 | { | |
40 | return strncmp (name, "_ZTV", 4) == 0; | |
41 | } | |
42 | ||
43 | static int | |
44 | gnuv3_is_operator_name (const char *name) | |
45 | { | |
46 | return strncmp (name, "operator", 8) == 0; | |
47 | } | |
48 | ||
49 | ||
50 | /* To help us find the components of a vtable, we build ourselves a | |
51 | GDB type object representing the vtable structure. Following the | |
52 | V3 ABI, it goes something like this: | |
53 | ||
54 | struct gdb_gnu_v3_abi_vtable { | |
55 | ||
56 | / * An array of virtual call and virtual base offsets. The real | |
57 | length of this array depends on the class hierarchy; we use | |
58 | negative subscripts to access the elements. Yucky, but | |
59 | better than the alternatives. * / | |
60 | ptrdiff_t vcall_and_vbase_offsets[0]; | |
61 | ||
62 | / * The offset from a virtual pointer referring to this table | |
63 | to the top of the complete object. * / | |
64 | ptrdiff_t offset_to_top; | |
65 | ||
66 | / * The type_info pointer for this class. This is really a | |
67 | std::type_info *, but GDB doesn't really look at the | |
68 | type_info object itself, so we don't bother to get the type | |
69 | exactly right. * / | |
70 | void *type_info; | |
71 | ||
72 | / * Virtual table pointers in objects point here. * / | |
73 | ||
74 | / * Virtual function pointers. Like the vcall/vbase array, the | |
75 | real length of this table depends on the class hierarchy. * / | |
76 | void (*virtual_functions[0]) (); | |
77 | ||
78 | }; | |
79 | ||
80 | The catch, of course, is that the exact layout of this table | |
81 | depends on the ABI --- word size, endianness, alignment, etc. So | |
82 | the GDB type object is actually a per-architecture kind of thing. | |
83 | ||
84 | vtable_type_gdbarch_data is a gdbarch per-architecture data pointer | |
85 | which refers to the struct type * for this structure, laid out | |
86 | appropriately for the architecture. */ | |
b27b8843 | 87 | static struct gdbarch_data *vtable_type_gdbarch_data; |
7ed49443 JB |
88 | |
89 | ||
90 | /* Human-readable names for the numbers of the fields above. */ | |
91 | enum { | |
92 | vtable_field_vcall_and_vbase_offsets, | |
93 | vtable_field_offset_to_top, | |
94 | vtable_field_type_info, | |
95 | vtable_field_virtual_functions | |
96 | }; | |
97 | ||
98 | ||
99 | /* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable', | |
100 | described above, laid out appropriately for ARCH. | |
101 | ||
102 | We use this function as the gdbarch per-architecture data | |
9970f04b | 103 | initialization function. */ |
7ed49443 JB |
104 | static void * |
105 | build_gdb_vtable_type (struct gdbarch *arch) | |
106 | { | |
107 | struct type *t; | |
108 | struct field *field_list, *field; | |
109 | int offset; | |
110 | ||
111 | struct type *void_ptr_type | |
fde6c819 | 112 | = builtin_type (arch)->builtin_data_ptr; |
7ed49443 | 113 | struct type *ptr_to_void_fn_type |
fde6c819 | 114 | = builtin_type (arch)->builtin_func_ptr; |
7ed49443 JB |
115 | |
116 | /* ARCH can't give us the true ptrdiff_t type, so we guess. */ | |
117 | struct type *ptrdiff_type | |
e9bb382b | 118 | = arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t"); |
7ed49443 JB |
119 | |
120 | /* We assume no padding is necessary, since GDB doesn't know | |
121 | anything about alignment at the moment. If this assumption bites | |
122 | us, we should add a gdbarch method which, given a type, returns | |
123 | the alignment that type requires, and then use that here. */ | |
124 | ||
125 | /* Build the field list. */ | |
126 | field_list = xmalloc (sizeof (struct field [4])); | |
127 | memset (field_list, 0, sizeof (struct field [4])); | |
128 | field = &field_list[0]; | |
129 | offset = 0; | |
130 | ||
131 | /* ptrdiff_t vcall_and_vbase_offsets[0]; */ | |
132 | FIELD_NAME (*field) = "vcall_and_vbase_offsets"; | |
e3506a9f | 133 | FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1); |
f41f5e61 | 134 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
135 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
136 | field++; | |
137 | ||
138 | /* ptrdiff_t offset_to_top; */ | |
139 | FIELD_NAME (*field) = "offset_to_top"; | |
140 | FIELD_TYPE (*field) = ptrdiff_type; | |
f41f5e61 | 141 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
142 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
143 | field++; | |
144 | ||
145 | /* void *type_info; */ | |
146 | FIELD_NAME (*field) = "type_info"; | |
147 | FIELD_TYPE (*field) = void_ptr_type; | |
f41f5e61 | 148 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
149 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
150 | field++; | |
151 | ||
152 | /* void (*virtual_functions[0]) (); */ | |
153 | FIELD_NAME (*field) = "virtual_functions"; | |
e3506a9f | 154 | FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1); |
f41f5e61 | 155 | SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); |
7ed49443 JB |
156 | offset += TYPE_LENGTH (FIELD_TYPE (*field)); |
157 | field++; | |
158 | ||
159 | /* We assumed in the allocation above that there were four fields. */ | |
3d499020 | 160 | gdb_assert (field == (field_list + 4)); |
7ed49443 | 161 | |
e9bb382b | 162 | t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL); |
7ed49443 JB |
163 | TYPE_NFIELDS (t) = field - field_list; |
164 | TYPE_FIELDS (t) = field_list; | |
165 | TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable"; | |
e9bb382b | 166 | INIT_CPLUS_SPECIFIC (t); |
7ed49443 JB |
167 | |
168 | return t; | |
169 | } | |
170 | ||
171 | ||
ed09d7da KB |
172 | /* Return the ptrdiff_t type used in the vtable type. */ |
173 | static struct type * | |
174 | vtable_ptrdiff_type (struct gdbarch *gdbarch) | |
175 | { | |
176 | struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data); | |
177 | ||
178 | /* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */ | |
179 | return TYPE_FIELD_TYPE (vtable_type, vtable_field_offset_to_top); | |
180 | } | |
181 | ||
7ed49443 JB |
182 | /* Return the offset from the start of the imaginary `struct |
183 | gdb_gnu_v3_abi_vtable' object to the vtable's "address point" | |
184 | (i.e., where objects' virtual table pointers point). */ | |
185 | static int | |
ad4820ab | 186 | vtable_address_point_offset (struct gdbarch *gdbarch) |
7ed49443 | 187 | { |
ad4820ab | 188 | struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data); |
7ed49443 JB |
189 | |
190 | return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions) | |
191 | / TARGET_CHAR_BIT); | |
192 | } | |
193 | ||
194 | ||
d48cc9dd DJ |
195 | /* Determine whether structure TYPE is a dynamic class. Cache the |
196 | result. */ | |
197 | ||
198 | static int | |
199 | gnuv3_dynamic_class (struct type *type) | |
200 | { | |
201 | int fieldnum, fieldelem; | |
202 | ||
203 | if (TYPE_CPLUS_DYNAMIC (type)) | |
204 | return TYPE_CPLUS_DYNAMIC (type) == 1; | |
205 | ||
206 | ALLOCATE_CPLUS_STRUCT_TYPE (type); | |
207 | ||
208 | for (fieldnum = 0; fieldnum < TYPE_N_BASECLASSES (type); fieldnum++) | |
209 | if (BASETYPE_VIA_VIRTUAL (type, fieldnum) | |
210 | || gnuv3_dynamic_class (TYPE_FIELD_TYPE (type, fieldnum))) | |
211 | { | |
212 | TYPE_CPLUS_DYNAMIC (type) = 1; | |
213 | return 1; | |
214 | } | |
215 | ||
216 | for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++) | |
217 | for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum); | |
218 | fieldelem++) | |
219 | { | |
220 | struct fn_field *f = TYPE_FN_FIELDLIST1 (type, fieldnum); | |
221 | ||
222 | if (TYPE_FN_FIELD_VIRTUAL_P (f, fieldelem)) | |
223 | { | |
224 | TYPE_CPLUS_DYNAMIC (type) = 1; | |
225 | return 1; | |
226 | } | |
227 | } | |
228 | ||
229 | TYPE_CPLUS_DYNAMIC (type) = -1; | |
230 | return 0; | |
231 | } | |
232 | ||
233 | /* Find the vtable for a value of CONTAINER_TYPE located at | |
234 | CONTAINER_ADDR. Return a value of the correct vtable type for this | |
235 | architecture, or NULL if CONTAINER does not have a vtable. */ | |
236 | ||
237 | static struct value * | |
238 | gnuv3_get_vtable (struct gdbarch *gdbarch, | |
239 | struct type *container_type, CORE_ADDR container_addr) | |
240 | { | |
241 | struct type *vtable_type = gdbarch_data (gdbarch, | |
242 | vtable_type_gdbarch_data); | |
243 | struct type *vtable_pointer_type; | |
244 | struct value *vtable_pointer; | |
245 | CORE_ADDR vtable_address; | |
246 | ||
247 | /* If this type does not have a virtual table, don't read the first | |
248 | field. */ | |
249 | if (!gnuv3_dynamic_class (check_typedef (container_type))) | |
250 | return NULL; | |
251 | ||
252 | /* We do not consult the debug information to find the virtual table. | |
253 | The ABI specifies that it is always at offset zero in any class, | |
254 | and debug information may not represent it. | |
255 | ||
256 | We avoid using value_contents on principle, because the object might | |
257 | be large. */ | |
258 | ||
259 | /* Find the type "pointer to virtual table". */ | |
260 | vtable_pointer_type = lookup_pointer_type (vtable_type); | |
261 | ||
262 | /* Load it from the start of the class. */ | |
263 | vtable_pointer = value_at (vtable_pointer_type, container_addr); | |
264 | vtable_address = value_as_address (vtable_pointer); | |
265 | ||
266 | /* Correct it to point at the start of the virtual table, rather | |
267 | than the address point. */ | |
268 | return value_at_lazy (vtable_type, | |
0963b4bd MS |
269 | vtable_address |
270 | - vtable_address_point_offset (gdbarch)); | |
d48cc9dd DJ |
271 | } |
272 | ||
273 | ||
7ed49443 JB |
274 | static struct type * |
275 | gnuv3_rtti_type (struct value *value, | |
276 | int *full_p, int *top_p, int *using_enc_p) | |
277 | { | |
ad4820ab | 278 | struct gdbarch *gdbarch; |
df407dfe | 279 | struct type *values_type = check_typedef (value_type (value)); |
7ed49443 JB |
280 | struct value *vtable; |
281 | struct minimal_symbol *vtable_symbol; | |
282 | const char *vtable_symbol_name; | |
283 | const char *class_name; | |
7ed49443 JB |
284 | struct type *run_time_type; |
285 | LONGEST offset_to_top; | |
8de20a37 | 286 | char *atsign; |
7ed49443 JB |
287 | |
288 | /* We only have RTTI for class objects. */ | |
df407dfe | 289 | if (TYPE_CODE (values_type) != TYPE_CODE_CLASS) |
7ed49443 JB |
290 | return NULL; |
291 | ||
eb2a6f42 TT |
292 | /* Java doesn't have RTTI following the C++ ABI. */ |
293 | if (TYPE_CPLUS_REALLY_JAVA (values_type)) | |
294 | return NULL; | |
295 | ||
ad4820ab | 296 | /* Determine architecture. */ |
50810684 | 297 | gdbarch = get_type_arch (values_type); |
7ed49443 | 298 | |
21cfb3b6 DJ |
299 | if (using_enc_p) |
300 | *using_enc_p = 0; | |
301 | ||
d48cc9dd DJ |
302 | vtable = gnuv3_get_vtable (gdbarch, value_type (value), |
303 | value_as_address (value_addr (value))); | |
304 | if (vtable == NULL) | |
305 | return NULL; | |
306 | ||
7ed49443 JB |
307 | /* Find the linker symbol for this vtable. */ |
308 | vtable_symbol | |
42ae5230 | 309 | = lookup_minimal_symbol_by_pc (value_address (vtable) |
7cbd4a93 | 310 | + value_embedded_offset (vtable)).minsym; |
7ed49443 JB |
311 | if (! vtable_symbol) |
312 | return NULL; | |
313 | ||
314 | /* The symbol's demangled name should be something like "vtable for | |
315 | CLASS", where CLASS is the name of the run-time type of VALUE. | |
316 | If we didn't like this approach, we could instead look in the | |
317 | type_info object itself to get the class name. But this way | |
318 | should work just as well, and doesn't read target memory. */ | |
319 | vtable_symbol_name = SYMBOL_DEMANGLED_NAME (vtable_symbol); | |
98081e55 PB |
320 | if (vtable_symbol_name == NULL |
321 | || strncmp (vtable_symbol_name, "vtable for ", 11)) | |
f773fdbb | 322 | { |
8a3fe4f8 | 323 | warning (_("can't find linker symbol for virtual table for `%s' value"), |
0a07729b | 324 | TYPE_SAFE_NAME (values_type)); |
f773fdbb | 325 | if (vtable_symbol_name) |
8a3fe4f8 | 326 | warning (_(" found `%s' instead"), vtable_symbol_name); |
f773fdbb JM |
327 | return NULL; |
328 | } | |
7ed49443 JB |
329 | class_name = vtable_symbol_name + 11; |
330 | ||
8de20a37 TT |
331 | /* Strip off @plt and version suffixes. */ |
332 | atsign = strchr (class_name, '@'); | |
333 | if (atsign != NULL) | |
334 | { | |
335 | char *copy; | |
336 | ||
337 | copy = alloca (atsign - class_name + 1); | |
338 | memcpy (copy, class_name, atsign - class_name); | |
339 | copy[atsign - class_name] = '\0'; | |
340 | class_name = copy; | |
341 | } | |
342 | ||
7ed49443 | 343 | /* Try to look up the class name as a type name. */ |
0963b4bd | 344 | /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */ |
362ff856 MC |
345 | run_time_type = cp_lookup_rtti_type (class_name, NULL); |
346 | if (run_time_type == NULL) | |
347 | return NULL; | |
7ed49443 JB |
348 | |
349 | /* Get the offset from VALUE to the top of the complete object. | |
350 | NOTE: this is the reverse of the meaning of *TOP_P. */ | |
351 | offset_to_top | |
352 | = value_as_long (value_field (vtable, vtable_field_offset_to_top)); | |
353 | ||
354 | if (full_p) | |
13c3b5f5 | 355 | *full_p = (- offset_to_top == value_embedded_offset (value) |
4754a64e | 356 | && (TYPE_LENGTH (value_enclosing_type (value)) |
7ed49443 JB |
357 | >= TYPE_LENGTH (run_time_type))); |
358 | if (top_p) | |
359 | *top_p = - offset_to_top; | |
7ed49443 JB |
360 | return run_time_type; |
361 | } | |
362 | ||
0d5de010 DJ |
363 | /* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual |
364 | function, of type FNTYPE. */ | |
7ed49443 | 365 | |
0d5de010 | 366 | static struct value * |
ad4820ab UW |
367 | gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container, |
368 | struct type *fntype, int vtable_index) | |
0d5de010 | 369 | { |
d48cc9dd DJ |
370 | struct value *vtable, *vfn; |
371 | ||
372 | /* Every class with virtual functions must have a vtable. */ | |
373 | vtable = gnuv3_get_vtable (gdbarch, value_type (container), | |
374 | value_as_address (value_addr (container))); | |
375 | gdb_assert (vtable != NULL); | |
7ed49443 JB |
376 | |
377 | /* Fetch the appropriate function pointer from the vtable. */ | |
378 | vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions), | |
2497b498 | 379 | vtable_index); |
7ed49443 | 380 | |
0d5de010 DJ |
381 | /* If this architecture uses function descriptors directly in the vtable, |
382 | then the address of the vtable entry is actually a "function pointer" | |
383 | (i.e. points to the descriptor). We don't need to scale the index | |
384 | by the size of a function descriptor; GCC does that before outputing | |
385 | debug information. */ | |
ad4820ab | 386 | if (gdbarch_vtable_function_descriptors (gdbarch)) |
0d5de010 | 387 | vfn = value_addr (vfn); |
7ed49443 | 388 | |
0d5de010 DJ |
389 | /* Cast the function pointer to the appropriate type. */ |
390 | vfn = value_cast (lookup_pointer_type (fntype), vfn); | |
76b79d6e | 391 | |
7ed49443 JB |
392 | return vfn; |
393 | } | |
394 | ||
0d5de010 DJ |
395 | /* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h |
396 | for a description of the arguments. */ | |
397 | ||
398 | static struct value * | |
399 | gnuv3_virtual_fn_field (struct value **value_p, | |
400 | struct fn_field *f, int j, | |
401 | struct type *vfn_base, int offset) | |
402 | { | |
403 | struct type *values_type = check_typedef (value_type (*value_p)); | |
ad4820ab | 404 | struct gdbarch *gdbarch; |
0d5de010 DJ |
405 | |
406 | /* Some simple sanity checks. */ | |
407 | if (TYPE_CODE (values_type) != TYPE_CODE_CLASS) | |
408 | error (_("Only classes can have virtual functions.")); | |
409 | ||
ad4820ab | 410 | /* Determine architecture. */ |
50810684 | 411 | gdbarch = get_type_arch (values_type); |
ad4820ab | 412 | |
0d5de010 DJ |
413 | /* Cast our value to the base class which defines this virtual |
414 | function. This takes care of any necessary `this' | |
415 | adjustments. */ | |
416 | if (vfn_base != values_type) | |
417 | *value_p = value_cast (vfn_base, *value_p); | |
418 | ||
ad4820ab | 419 | return gnuv3_get_virtual_fn (gdbarch, *value_p, TYPE_FN_FIELD_TYPE (f, j), |
0d5de010 DJ |
420 | TYPE_FN_FIELD_VOFFSET (f, j)); |
421 | } | |
422 | ||
1514d34e DJ |
423 | /* Compute the offset of the baseclass which is |
424 | the INDEXth baseclass of class TYPE, | |
425 | for value at VALADDR (in host) at ADDRESS (in target). | |
426 | The result is the offset of the baseclass value relative | |
427 | to (the address of)(ARG) + OFFSET. | |
428 | ||
0963b4bd MS |
429 | -1 is returned on error. */ |
430 | ||
b9362cc7 | 431 | static int |
8af8e3bc PA |
432 | gnuv3_baseclass_offset (struct type *type, int index, |
433 | const bfd_byte *valaddr, int embedded_offset, | |
434 | CORE_ADDR address, const struct value *val) | |
1514d34e | 435 | { |
ad4820ab | 436 | struct gdbarch *gdbarch; |
ad4820ab | 437 | struct type *ptr_type; |
79d5b63a | 438 | struct value *vtable; |
2497b498 | 439 | struct value *vbase_array; |
1514d34e | 440 | long int cur_base_offset, base_offset; |
1514d34e | 441 | |
ad4820ab | 442 | /* Determine architecture. */ |
50810684 | 443 | gdbarch = get_type_arch (type); |
ad4820ab UW |
444 | ptr_type = builtin_type (gdbarch)->builtin_data_ptr; |
445 | ||
1514d34e | 446 | /* If it isn't a virtual base, this is easy. The offset is in the |
b1af9e97 TT |
447 | type definition. Likewise for Java, which doesn't really have |
448 | virtual inheritance in the C++ sense. */ | |
449 | if (!BASETYPE_VIA_VIRTUAL (type, index) || TYPE_CPLUS_REALLY_JAVA (type)) | |
1514d34e DJ |
450 | return TYPE_BASECLASS_BITPOS (type, index) / 8; |
451 | ||
452 | /* To access a virtual base, we need to use the vbase offset stored in | |
453 | our vtable. Recent GCC versions provide this information. If it isn't | |
454 | available, we could get what we needed from RTTI, or from drawing the | |
455 | complete inheritance graph based on the debug info. Neither is | |
456 | worthwhile. */ | |
457 | cur_base_offset = TYPE_BASECLASS_BITPOS (type, index) / 8; | |
ad4820ab | 458 | if (cur_base_offset >= - vtable_address_point_offset (gdbarch)) |
8a3fe4f8 | 459 | error (_("Expected a negative vbase offset (old compiler?)")); |
1514d34e | 460 | |
ad4820ab UW |
461 | cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch); |
462 | if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0) | |
8a3fe4f8 | 463 | error (_("Misaligned vbase offset.")); |
ad4820ab | 464 | cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type)); |
1514d34e | 465 | |
8af8e3bc | 466 | vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset); |
d48cc9dd | 467 | gdb_assert (vtable != NULL); |
1514d34e | 468 | vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets); |
2497b498 | 469 | base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset)); |
1514d34e DJ |
470 | return base_offset; |
471 | } | |
7ed49443 | 472 | |
0d5de010 DJ |
473 | /* Locate a virtual method in DOMAIN or its non-virtual base classes |
474 | which has virtual table index VOFFSET. The method has an associated | |
475 | "this" adjustment of ADJUSTMENT bytes. */ | |
476 | ||
2c0b251b | 477 | static const char * |
0d5de010 DJ |
478 | gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset, |
479 | LONGEST adjustment) | |
480 | { | |
481 | int i; | |
0d5de010 DJ |
482 | |
483 | /* Search this class first. */ | |
0d5de010 DJ |
484 | if (adjustment == 0) |
485 | { | |
486 | int len; | |
487 | ||
488 | len = TYPE_NFN_FIELDS (domain); | |
489 | for (i = 0; i < len; i++) | |
490 | { | |
491 | int len2, j; | |
492 | struct fn_field *f; | |
493 | ||
494 | f = TYPE_FN_FIELDLIST1 (domain, i); | |
495 | len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i); | |
496 | ||
497 | check_stub_method_group (domain, i); | |
498 | for (j = 0; j < len2; j++) | |
499 | if (TYPE_FN_FIELD_VOFFSET (f, j) == voffset) | |
500 | return TYPE_FN_FIELD_PHYSNAME (f, j); | |
501 | } | |
502 | } | |
503 | ||
504 | /* Next search non-virtual bases. If it's in a virtual base, | |
505 | we're out of luck. */ | |
506 | for (i = 0; i < TYPE_N_BASECLASSES (domain); i++) | |
507 | { | |
508 | int pos; | |
509 | struct type *basetype; | |
510 | ||
511 | if (BASETYPE_VIA_VIRTUAL (domain, i)) | |
512 | continue; | |
513 | ||
514 | pos = TYPE_BASECLASS_BITPOS (domain, i) / 8; | |
515 | basetype = TYPE_FIELD_TYPE (domain, i); | |
516 | /* Recurse with a modified adjustment. We don't need to adjust | |
517 | voffset. */ | |
518 | if (adjustment >= pos && adjustment < pos + TYPE_LENGTH (basetype)) | |
519 | return gnuv3_find_method_in (basetype, voffset, adjustment - pos); | |
520 | } | |
521 | ||
522 | return NULL; | |
523 | } | |
524 | ||
fead6908 UW |
525 | /* Decode GNU v3 method pointer. */ |
526 | ||
527 | static int | |
ad4820ab UW |
528 | gnuv3_decode_method_ptr (struct gdbarch *gdbarch, |
529 | const gdb_byte *contents, | |
fead6908 UW |
530 | CORE_ADDR *value_p, |
531 | LONGEST *adjustment_p) | |
532 | { | |
ad4820ab | 533 | struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr; |
ed09d7da | 534 | struct type *offset_type = vtable_ptrdiff_type (gdbarch); |
e17a4113 | 535 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
fead6908 UW |
536 | CORE_ADDR ptr_value; |
537 | LONGEST voffset, adjustment; | |
538 | int vbit; | |
539 | ||
540 | /* Extract the pointer to member. The first element is either a pointer | |
541 | or a vtable offset. For pointers, we need to use extract_typed_address | |
542 | to allow the back-end to convert the pointer to a GDB address -- but | |
543 | vtable offsets we must handle as integers. At this point, we do not | |
544 | yet know which case we have, so we extract the value under both | |
545 | interpretations and choose the right one later on. */ | |
546 | ptr_value = extract_typed_address (contents, funcptr_type); | |
e17a4113 UW |
547 | voffset = extract_signed_integer (contents, |
548 | TYPE_LENGTH (funcptr_type), byte_order); | |
fead6908 | 549 | contents += TYPE_LENGTH (funcptr_type); |
e17a4113 UW |
550 | adjustment = extract_signed_integer (contents, |
551 | TYPE_LENGTH (offset_type), byte_order); | |
fead6908 | 552 | |
ad4820ab | 553 | if (!gdbarch_vbit_in_delta (gdbarch)) |
fead6908 UW |
554 | { |
555 | vbit = voffset & 1; | |
556 | voffset = voffset ^ vbit; | |
557 | } | |
558 | else | |
559 | { | |
560 | vbit = adjustment & 1; | |
561 | adjustment = adjustment >> 1; | |
562 | } | |
563 | ||
564 | *value_p = vbit? voffset : ptr_value; | |
565 | *adjustment_p = adjustment; | |
566 | return vbit; | |
567 | } | |
568 | ||
0d5de010 DJ |
569 | /* GNU v3 implementation of cplus_print_method_ptr. */ |
570 | ||
571 | static void | |
572 | gnuv3_print_method_ptr (const gdb_byte *contents, | |
573 | struct type *type, | |
574 | struct ui_file *stream) | |
575 | { | |
ad4820ab | 576 | struct type *domain = TYPE_DOMAIN_TYPE (type); |
50810684 | 577 | struct gdbarch *gdbarch = get_type_arch (domain); |
0d5de010 DJ |
578 | CORE_ADDR ptr_value; |
579 | LONGEST adjustment; | |
0d5de010 DJ |
580 | int vbit; |
581 | ||
0d5de010 | 582 | /* Extract the pointer to member. */ |
ad4820ab | 583 | vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment); |
0d5de010 DJ |
584 | |
585 | /* Check for NULL. */ | |
586 | if (ptr_value == 0 && vbit == 0) | |
587 | { | |
588 | fprintf_filtered (stream, "NULL"); | |
589 | return; | |
590 | } | |
591 | ||
592 | /* Search for a virtual method. */ | |
593 | if (vbit) | |
594 | { | |
595 | CORE_ADDR voffset; | |
596 | const char *physname; | |
597 | ||
598 | /* It's a virtual table offset, maybe in this class. Search | |
599 | for a field with the correct vtable offset. First convert it | |
600 | to an index, as used in TYPE_FN_FIELD_VOFFSET. */ | |
ed09d7da | 601 | voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch)); |
0d5de010 DJ |
602 | |
603 | physname = gnuv3_find_method_in (domain, voffset, adjustment); | |
604 | ||
605 | /* If we found a method, print that. We don't bother to disambiguate | |
606 | possible paths to the method based on the adjustment. */ | |
607 | if (physname) | |
608 | { | |
8de20a37 TT |
609 | char *demangled_name = gdb_demangle (physname, |
610 | DMGL_ANSI | DMGL_PARAMS); | |
d8734c88 | 611 | |
94af9270 KS |
612 | fprintf_filtered (stream, "&virtual "); |
613 | if (demangled_name == NULL) | |
614 | fputs_filtered (physname, stream); | |
615 | else | |
0d5de010 | 616 | { |
0d5de010 DJ |
617 | fputs_filtered (demangled_name, stream); |
618 | xfree (demangled_name); | |
0d5de010 | 619 | } |
94af9270 | 620 | return; |
0d5de010 DJ |
621 | } |
622 | } | |
94af9270 KS |
623 | else if (ptr_value != 0) |
624 | { | |
625 | /* Found a non-virtual function: print out the type. */ | |
626 | fputs_filtered ("(", stream); | |
79d43c61 | 627 | c_print_type (type, "", stream, -1, 0, &type_print_raw_options); |
94af9270 KS |
628 | fputs_filtered (") ", stream); |
629 | } | |
0d5de010 DJ |
630 | |
631 | /* We didn't find it; print the raw data. */ | |
632 | if (vbit) | |
633 | { | |
634 | fprintf_filtered (stream, "&virtual table offset "); | |
635 | print_longest (stream, 'd', 1, ptr_value); | |
636 | } | |
637 | else | |
edf0c1b7 TT |
638 | { |
639 | struct value_print_options opts; | |
640 | ||
641 | get_user_print_options (&opts); | |
642 | print_address_demangle (&opts, gdbarch, ptr_value, stream, demangle); | |
643 | } | |
0d5de010 DJ |
644 | |
645 | if (adjustment) | |
646 | { | |
647 | fprintf_filtered (stream, ", this adjustment "); | |
648 | print_longest (stream, 'd', 1, adjustment); | |
649 | } | |
650 | } | |
651 | ||
652 | /* GNU v3 implementation of cplus_method_ptr_size. */ | |
653 | ||
654 | static int | |
ad4820ab | 655 | gnuv3_method_ptr_size (struct type *type) |
0d5de010 | 656 | { |
561d3825 | 657 | struct gdbarch *gdbarch = get_type_arch (type); |
d8734c88 | 658 | |
ad4820ab | 659 | return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr); |
0d5de010 DJ |
660 | } |
661 | ||
662 | /* GNU v3 implementation of cplus_make_method_ptr. */ | |
663 | ||
664 | static void | |
ad4820ab UW |
665 | gnuv3_make_method_ptr (struct type *type, gdb_byte *contents, |
666 | CORE_ADDR value, int is_virtual) | |
0d5de010 | 667 | { |
561d3825 | 668 | struct gdbarch *gdbarch = get_type_arch (type); |
ad4820ab | 669 | int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr); |
e17a4113 | 670 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
0d5de010 DJ |
671 | |
672 | /* FIXME drow/2006-12-24: The adjustment of "this" is currently | |
673 | always zero, since the method pointer is of the correct type. | |
674 | But if the method pointer came from a base class, this is | |
675 | incorrect - it should be the offset to the base. The best | |
676 | fix might be to create the pointer to member pointing at the | |
677 | base class and cast it to the derived class, but that requires | |
678 | support for adjusting pointers to members when casting them - | |
679 | not currently supported by GDB. */ | |
680 | ||
ad4820ab | 681 | if (!gdbarch_vbit_in_delta (gdbarch)) |
0d5de010 | 682 | { |
e17a4113 UW |
683 | store_unsigned_integer (contents, size, byte_order, value | is_virtual); |
684 | store_unsigned_integer (contents + size, size, byte_order, 0); | |
0d5de010 DJ |
685 | } |
686 | else | |
687 | { | |
e17a4113 UW |
688 | store_unsigned_integer (contents, size, byte_order, value); |
689 | store_unsigned_integer (contents + size, size, byte_order, is_virtual); | |
0d5de010 DJ |
690 | } |
691 | } | |
692 | ||
693 | /* GNU v3 implementation of cplus_method_ptr_to_value. */ | |
694 | ||
695 | static struct value * | |
696 | gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr) | |
697 | { | |
ad4820ab | 698 | struct gdbarch *gdbarch; |
0d5de010 DJ |
699 | const gdb_byte *contents = value_contents (method_ptr); |
700 | CORE_ADDR ptr_value; | |
ad4820ab | 701 | struct type *domain_type, *final_type, *method_type; |
0d5de010 | 702 | LONGEST adjustment; |
0d5de010 DJ |
703 | int vbit; |
704 | ||
ad4820ab UW |
705 | domain_type = TYPE_DOMAIN_TYPE (check_typedef (value_type (method_ptr))); |
706 | final_type = lookup_pointer_type (domain_type); | |
0d5de010 DJ |
707 | |
708 | method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr))); | |
709 | ||
fead6908 | 710 | /* Extract the pointer to member. */ |
50810684 | 711 | gdbarch = get_type_arch (domain_type); |
ad4820ab | 712 | vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment); |
0d5de010 DJ |
713 | |
714 | /* First convert THIS to match the containing type of the pointer to | |
715 | member. This cast may adjust the value of THIS. */ | |
716 | *this_p = value_cast (final_type, *this_p); | |
717 | ||
718 | /* Then apply whatever adjustment is necessary. This creates a somewhat | |
719 | strange pointer: it claims to have type FINAL_TYPE, but in fact it | |
720 | might not be a valid FINAL_TYPE. For instance, it might be a | |
721 | base class of FINAL_TYPE. And if it's not the primary base class, | |
722 | then printing it out as a FINAL_TYPE object would produce some pretty | |
723 | garbage. | |
724 | ||
725 | But we don't really know the type of the first argument in | |
726 | METHOD_TYPE either, which is why this happens. We can't | |
727 | dereference this later as a FINAL_TYPE, but once we arrive in the | |
728 | called method we'll have debugging information for the type of | |
729 | "this" - and that'll match the value we produce here. | |
730 | ||
731 | You can provoke this case by casting a Base::* to a Derived::*, for | |
732 | instance. */ | |
ad4820ab | 733 | *this_p = value_cast (builtin_type (gdbarch)->builtin_data_ptr, *this_p); |
2497b498 | 734 | *this_p = value_ptradd (*this_p, adjustment); |
0d5de010 DJ |
735 | *this_p = value_cast (final_type, *this_p); |
736 | ||
737 | if (vbit) | |
738 | { | |
ad4820ab | 739 | LONGEST voffset; |
d8734c88 | 740 | |
ed09d7da | 741 | voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch)); |
ad4820ab UW |
742 | return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p), |
743 | method_type, voffset); | |
0d5de010 DJ |
744 | } |
745 | else | |
746 | return value_from_pointer (lookup_pointer_type (method_type), ptr_value); | |
747 | } | |
748 | ||
c4aeac85 TT |
749 | /* Objects of this type are stored in a hash table and a vector when |
750 | printing the vtables for a class. */ | |
751 | ||
752 | struct value_and_voffset | |
753 | { | |
754 | /* The value representing the object. */ | |
755 | struct value *value; | |
756 | ||
757 | /* The maximum vtable offset we've found for any object at this | |
758 | offset in the outermost object. */ | |
759 | int max_voffset; | |
760 | }; | |
761 | ||
762 | typedef struct value_and_voffset *value_and_voffset_p; | |
763 | DEF_VEC_P (value_and_voffset_p); | |
764 | ||
765 | /* Hash function for value_and_voffset. */ | |
766 | ||
767 | static hashval_t | |
768 | hash_value_and_voffset (const void *p) | |
769 | { | |
770 | const struct value_and_voffset *o = p; | |
771 | ||
772 | return value_address (o->value) + value_embedded_offset (o->value); | |
773 | } | |
774 | ||
775 | /* Equality function for value_and_voffset. */ | |
776 | ||
777 | static int | |
778 | eq_value_and_voffset (const void *a, const void *b) | |
779 | { | |
780 | const struct value_and_voffset *ova = a; | |
781 | const struct value_and_voffset *ovb = b; | |
782 | ||
783 | return (value_address (ova->value) + value_embedded_offset (ova->value) | |
784 | == value_address (ovb->value) + value_embedded_offset (ovb->value)); | |
785 | } | |
786 | ||
787 | /* qsort comparison function for value_and_voffset. */ | |
788 | ||
789 | static int | |
790 | compare_value_and_voffset (const void *a, const void *b) | |
791 | { | |
792 | const struct value_and_voffset * const *ova = a; | |
793 | CORE_ADDR addra = (value_address ((*ova)->value) | |
794 | + value_embedded_offset ((*ova)->value)); | |
795 | const struct value_and_voffset * const *ovb = b; | |
796 | CORE_ADDR addrb = (value_address ((*ovb)->value) | |
797 | + value_embedded_offset ((*ovb)->value)); | |
798 | ||
799 | if (addra < addrb) | |
800 | return -1; | |
801 | if (addra > addrb) | |
802 | return 1; | |
803 | return 0; | |
804 | } | |
805 | ||
806 | /* A helper function used when printing vtables. This determines the | |
807 | key (most derived) sub-object at each address and also computes the | |
808 | maximum vtable offset seen for the corresponding vtable. Updates | |
809 | OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if | |
810 | needed. VALUE is the object to examine. */ | |
811 | ||
812 | static void | |
813 | compute_vtable_size (htab_t offset_hash, | |
814 | VEC (value_and_voffset_p) **offset_vec, | |
815 | struct value *value) | |
816 | { | |
817 | int i; | |
818 | struct type *type = check_typedef (value_type (value)); | |
819 | void **slot; | |
820 | struct value_and_voffset search_vo, *current_vo; | |
c4aeac85 TT |
821 | |
822 | /* If the object is not dynamic, then we are done; as it cannot have | |
823 | dynamic base types either. */ | |
824 | if (!gnuv3_dynamic_class (type)) | |
825 | return; | |
826 | ||
827 | /* Update the hash and the vec, if needed. */ | |
828 | search_vo.value = value; | |
829 | slot = htab_find_slot (offset_hash, &search_vo, INSERT); | |
830 | if (*slot) | |
831 | current_vo = *slot; | |
832 | else | |
833 | { | |
834 | current_vo = XNEW (struct value_and_voffset); | |
835 | current_vo->value = value; | |
836 | current_vo->max_voffset = -1; | |
837 | *slot = current_vo; | |
838 | VEC_safe_push (value_and_voffset_p, *offset_vec, current_vo); | |
839 | } | |
840 | ||
841 | /* Update the value_and_voffset object with the highest vtable | |
842 | offset from this class. */ | |
843 | for (i = 0; i < TYPE_NFN_FIELDS (type); ++i) | |
844 | { | |
845 | int j; | |
846 | struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, i); | |
847 | ||
848 | for (j = 0; j < TYPE_FN_FIELDLIST_LENGTH (type, i); ++j) | |
849 | { | |
850 | if (TYPE_FN_FIELD_VIRTUAL_P (fn, j)) | |
851 | { | |
852 | int voffset = TYPE_FN_FIELD_VOFFSET (fn, j); | |
853 | ||
854 | if (voffset > current_vo->max_voffset) | |
855 | current_vo->max_voffset = voffset; | |
856 | } | |
857 | } | |
858 | } | |
859 | ||
860 | /* Recurse into base classes. */ | |
861 | for (i = 0; i < TYPE_N_BASECLASSES (type); ++i) | |
862 | compute_vtable_size (offset_hash, offset_vec, value_field (value, i)); | |
863 | } | |
864 | ||
865 | /* Helper for gnuv3_print_vtable that prints a single vtable. */ | |
866 | ||
867 | static void | |
868 | print_one_vtable (struct gdbarch *gdbarch, struct value *value, | |
869 | int max_voffset, | |
870 | struct value_print_options *opts) | |
871 | { | |
872 | int i; | |
873 | struct type *type = check_typedef (value_type (value)); | |
874 | struct value *vtable; | |
875 | CORE_ADDR vt_addr; | |
876 | ||
877 | vtable = gnuv3_get_vtable (gdbarch, type, | |
878 | value_address (value) | |
879 | + value_embedded_offset (value)); | |
880 | vt_addr = value_address (value_field (vtable, | |
881 | vtable_field_virtual_functions)); | |
882 | ||
883 | printf_filtered (_("vtable for '%s' @ %s (subobject @ %s):\n"), | |
884 | TYPE_SAFE_NAME (type), | |
885 | paddress (gdbarch, vt_addr), | |
886 | paddress (gdbarch, (value_address (value) | |
887 | + value_embedded_offset (value)))); | |
888 | ||
889 | for (i = 0; i <= max_voffset; ++i) | |
890 | { | |
cafe75b0 JK |
891 | /* Initialize it just to avoid a GCC false warning. */ |
892 | CORE_ADDR addr = 0; | |
c4aeac85 | 893 | struct value *vfn; |
c4aeac85 TT |
894 | volatile struct gdb_exception ex; |
895 | ||
896 | printf_filtered ("[%d]: ", i); | |
897 | ||
898 | vfn = value_subscript (value_field (vtable, | |
899 | vtable_field_virtual_functions), | |
900 | i); | |
901 | ||
902 | if (gdbarch_vtable_function_descriptors (gdbarch)) | |
903 | vfn = value_addr (vfn); | |
904 | ||
905 | TRY_CATCH (ex, RETURN_MASK_ERROR) | |
906 | { | |
907 | addr = value_as_address (vfn); | |
908 | } | |
909 | if (ex.reason < 0) | |
910 | printf_filtered (_("<error: %s>"), ex.message); | |
911 | else | |
edf0c1b7 | 912 | print_function_pointer_address (opts, gdbarch, addr, gdb_stdout); |
c4aeac85 TT |
913 | printf_filtered ("\n"); |
914 | } | |
915 | } | |
916 | ||
917 | /* Implementation of the print_vtable method. */ | |
918 | ||
919 | static void | |
920 | gnuv3_print_vtable (struct value *value) | |
921 | { | |
922 | struct gdbarch *gdbarch; | |
923 | struct type *type; | |
924 | struct value *vtable; | |
925 | struct value_print_options opts; | |
926 | htab_t offset_hash; | |
927 | struct cleanup *cleanup; | |
5ff5c7b4 | 928 | VEC (value_and_voffset_p) *result_vec = NULL; |
c4aeac85 TT |
929 | struct value_and_voffset *iter; |
930 | int i, count; | |
931 | ||
932 | value = coerce_ref (value); | |
933 | type = check_typedef (value_type (value)); | |
934 | if (TYPE_CODE (type) == TYPE_CODE_PTR) | |
935 | { | |
936 | value = value_ind (value); | |
937 | type = check_typedef (value_type (value)); | |
938 | } | |
939 | ||
940 | get_user_print_options (&opts); | |
941 | ||
942 | /* Respect 'set print object'. */ | |
943 | if (opts.objectprint) | |
944 | { | |
945 | value = value_full_object (value, NULL, 0, 0, 0); | |
946 | type = check_typedef (value_type (value)); | |
947 | } | |
948 | ||
949 | gdbarch = get_type_arch (type); | |
950 | vtable = gnuv3_get_vtable (gdbarch, type, | |
951 | value_as_address (value_addr (value))); | |
952 | ||
953 | if (!vtable) | |
954 | { | |
955 | printf_filtered (_("This object does not have a virtual function table\n")); | |
956 | return; | |
957 | } | |
958 | ||
959 | offset_hash = htab_create_alloc (1, hash_value_and_voffset, | |
960 | eq_value_and_voffset, | |
961 | xfree, xcalloc, xfree); | |
962 | cleanup = make_cleanup_htab_delete (offset_hash); | |
963 | make_cleanup (VEC_cleanup (value_and_voffset_p), &result_vec); | |
964 | ||
965 | compute_vtable_size (offset_hash, &result_vec, value); | |
966 | ||
967 | qsort (VEC_address (value_and_voffset_p, result_vec), | |
968 | VEC_length (value_and_voffset_p, result_vec), | |
969 | sizeof (value_and_voffset_p), | |
970 | compare_value_and_voffset); | |
971 | ||
972 | count = 0; | |
973 | for (i = 0; VEC_iterate (value_and_voffset_p, result_vec, i, iter); ++i) | |
974 | { | |
975 | if (iter->max_voffset >= 0) | |
976 | { | |
977 | if (count > 0) | |
978 | printf_filtered ("\n"); | |
979 | print_one_vtable (gdbarch, iter->value, iter->max_voffset, &opts); | |
980 | ++count; | |
981 | } | |
982 | } | |
983 | ||
984 | do_cleanups (cleanup); | |
985 | } | |
986 | ||
b18be20d DJ |
987 | /* Determine if we are currently in a C++ thunk. If so, get the address |
988 | of the routine we are thunking to and continue to there instead. */ | |
989 | ||
990 | static CORE_ADDR | |
52f729a7 | 991 | gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc) |
b18be20d DJ |
992 | { |
993 | CORE_ADDR real_stop_pc, method_stop_pc; | |
9970f04b | 994 | struct gdbarch *gdbarch = get_frame_arch (frame); |
b18be20d DJ |
995 | struct minimal_symbol *thunk_sym, *fn_sym; |
996 | struct obj_section *section; | |
0d5cff50 | 997 | const char *thunk_name, *fn_name; |
b18be20d | 998 | |
9970f04b | 999 | real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc); |
b18be20d DJ |
1000 | if (real_stop_pc == 0) |
1001 | real_stop_pc = stop_pc; | |
1002 | ||
1003 | /* Find the linker symbol for this potential thunk. */ | |
7cbd4a93 | 1004 | thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc).minsym; |
b18be20d DJ |
1005 | section = find_pc_section (real_stop_pc); |
1006 | if (thunk_sym == NULL || section == NULL) | |
1007 | return 0; | |
1008 | ||
1009 | /* The symbol's demangled name should be something like "virtual | |
1010 | thunk to FUNCTION", where FUNCTION is the name of the function | |
1011 | being thunked to. */ | |
1012 | thunk_name = SYMBOL_DEMANGLED_NAME (thunk_sym); | |
1013 | if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL) | |
1014 | return 0; | |
1015 | ||
1016 | fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to "); | |
1017 | fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile); | |
1018 | if (fn_sym == NULL) | |
1019 | return 0; | |
1020 | ||
1021 | method_stop_pc = SYMBOL_VALUE_ADDRESS (fn_sym); | |
e76f05fa | 1022 | real_stop_pc = gdbarch_skip_trampoline_code |
9970f04b | 1023 | (gdbarch, frame, method_stop_pc); |
b18be20d DJ |
1024 | if (real_stop_pc == 0) |
1025 | real_stop_pc = method_stop_pc; | |
1026 | ||
1027 | return real_stop_pc; | |
1028 | } | |
1029 | ||
41f1b697 DJ |
1030 | /* Return nonzero if a type should be passed by reference. |
1031 | ||
1032 | The rule in the v3 ABI document comes from section 3.1.1. If the | |
1033 | type has a non-trivial copy constructor or destructor, then the | |
1034 | caller must make a copy (by calling the copy constructor if there | |
1035 | is one or perform the copy itself otherwise), pass the address of | |
1036 | the copy, and then destroy the temporary (if necessary). | |
1037 | ||
1038 | For return values with non-trivial copy constructors or | |
1039 | destructors, space will be allocated in the caller, and a pointer | |
1040 | will be passed as the first argument (preceding "this"). | |
1041 | ||
1042 | We don't have a bulletproof mechanism for determining whether a | |
1043 | constructor or destructor is trivial. For GCC and DWARF2 debug | |
1044 | information, we can check the artificial flag. | |
1045 | ||
1046 | We don't do anything with the constructors or destructors, | |
1047 | but we have to get the argument passing right anyway. */ | |
1048 | static int | |
1049 | gnuv3_pass_by_reference (struct type *type) | |
1050 | { | |
1051 | int fieldnum, fieldelem; | |
1052 | ||
1053 | CHECK_TYPEDEF (type); | |
1054 | ||
1055 | /* We're only interested in things that can have methods. */ | |
1056 | if (TYPE_CODE (type) != TYPE_CODE_STRUCT | |
1057 | && TYPE_CODE (type) != TYPE_CODE_CLASS | |
1058 | && TYPE_CODE (type) != TYPE_CODE_UNION) | |
1059 | return 0; | |
1060 | ||
1061 | for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++) | |
1062 | for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum); | |
1063 | fieldelem++) | |
1064 | { | |
1065 | struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum); | |
0d5cff50 | 1066 | const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum); |
41f1b697 DJ |
1067 | struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem); |
1068 | ||
1069 | /* If this function is marked as artificial, it is compiler-generated, | |
1070 | and we assume it is trivial. */ | |
1071 | if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem)) | |
1072 | continue; | |
1073 | ||
1074 | /* If we've found a destructor, we must pass this by reference. */ | |
1075 | if (name[0] == '~') | |
1076 | return 1; | |
1077 | ||
1078 | /* If the mangled name of this method doesn't indicate that it | |
1079 | is a constructor, we're not interested. | |
1080 | ||
1081 | FIXME drow/2007-09-23: We could do this using the name of | |
1082 | the method and the name of the class instead of dealing | |
1083 | with the mangled name. We don't have a convenient function | |
1084 | to strip off both leading scope qualifiers and trailing | |
1085 | template arguments yet. */ | |
7d27a96d TT |
1086 | if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem)) |
1087 | && !TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem)) | |
41f1b697 DJ |
1088 | continue; |
1089 | ||
1090 | /* If this method takes two arguments, and the second argument is | |
1091 | a reference to this class, then it is a copy constructor. */ | |
1092 | if (TYPE_NFIELDS (fieldtype) == 2 | |
1093 | && TYPE_CODE (TYPE_FIELD_TYPE (fieldtype, 1)) == TYPE_CODE_REF | |
0963b4bd MS |
1094 | && check_typedef (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (fieldtype, |
1095 | 1))) == type) | |
41f1b697 DJ |
1096 | return 1; |
1097 | } | |
1098 | ||
1099 | /* Even if all the constructors and destructors were artificial, one | |
1100 | of them may have invoked a non-artificial constructor or | |
1101 | destructor in a base class. If any base class needs to be passed | |
1102 | by reference, so does this class. Similarly for members, which | |
1103 | are constructed whenever this class is. We do not need to worry | |
1104 | about recursive loops here, since we are only looking at members | |
bceffbf3 | 1105 | of complete class type. Also ignore any static members. */ |
41f1b697 | 1106 | for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++) |
bceffbf3 JK |
1107 | if (! field_is_static (&TYPE_FIELD (type, fieldnum)) |
1108 | && gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum))) | |
41f1b697 DJ |
1109 | return 1; |
1110 | ||
1111 | return 0; | |
1112 | } | |
1113 | ||
7ed49443 JB |
1114 | static void |
1115 | init_gnuv3_ops (void) | |
1116 | { | |
0963b4bd MS |
1117 | vtable_type_gdbarch_data |
1118 | = gdbarch_data_register_post_init (build_gdb_vtable_type); | |
7ed49443 JB |
1119 | |
1120 | gnu_v3_abi_ops.shortname = "gnu-v3"; | |
1121 | gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI"; | |
1122 | gnu_v3_abi_ops.doc = "G++ Version 3 ABI"; | |
358777b0 EZ |
1123 | gnu_v3_abi_ops.is_destructor_name = |
1124 | (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor; | |
1125 | gnu_v3_abi_ops.is_constructor_name = | |
1126 | (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor; | |
7ed49443 JB |
1127 | gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name; |
1128 | gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name; | |
1129 | gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type; | |
1130 | gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field; | |
1514d34e | 1131 | gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset; |
0d5de010 DJ |
1132 | gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr; |
1133 | gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size; | |
1134 | gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr; | |
1135 | gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value; | |
c4aeac85 | 1136 | gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable; |
b18be20d | 1137 | gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline; |
41f1b697 | 1138 | gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference; |
7ed49443 JB |
1139 | } |
1140 | ||
b9362cc7 | 1141 | extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */ |
7ed49443 JB |
1142 | |
1143 | void | |
1144 | _initialize_gnu_v3_abi (void) | |
1145 | { | |
1146 | init_gnuv3_ops (); | |
1147 | ||
fe1f4a5e | 1148 | register_cp_abi (&gnu_v3_abi_ops); |
1605ef26 | 1149 | set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname); |
7ed49443 | 1150 | } |