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