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7ed49443
JB
1/* Abstraction of GNU v3 abi.
2 Contributed by Jim Blandy <jimb@redhat.com>
451fbdda 3
32d0add0 4 Copyright (C) 2001-2015 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
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20
21#include "defs.h"
22#include "value.h"
23#include "cp-abi.h"
362ff856 24#include "cp-support.h"
7ed49443 25#include "demangle.h"
b18be20d 26#include "objfiles.h"
0d5de010 27#include "valprint.h"
94af9270 28#include "c-lang.h"
79d43c61 29#include "typeprint.h"
0d5de010 30
b27b8843 31static struct cp_abi_ops gnu_v3_abi_ops;
7ed49443 32
6e72ca20
TT
33/* A gdbarch key for std::type_info, in the event that it can't be
34 found in the debug info. */
35
36static struct gdbarch_data *std_type_info_gdbarch_data;
37
38
7ed49443
JB
39static int
40gnuv3_is_vtable_name (const char *name)
41{
61012eef 42 return startswith (name, "_ZTV");
7ed49443
JB
43}
44
45static int
46gnuv3_is_operator_name (const char *name)
47{
61012eef 48 return startswith (name, "operator");
7ed49443
JB
49}
50
51
52/* To help us find the components of a vtable, we build ourselves a
53 GDB type object representing the vtable structure. Following the
54 V3 ABI, it goes something like this:
55
56 struct gdb_gnu_v3_abi_vtable {
57
58 / * An array of virtual call and virtual base offsets. The real
59 length of this array depends on the class hierarchy; we use
60 negative subscripts to access the elements. Yucky, but
61 better than the alternatives. * /
62 ptrdiff_t vcall_and_vbase_offsets[0];
63
64 / * The offset from a virtual pointer referring to this table
65 to the top of the complete object. * /
66 ptrdiff_t offset_to_top;
67
68 / * The type_info pointer for this class. This is really a
69 std::type_info *, but GDB doesn't really look at the
70 type_info object itself, so we don't bother to get the type
71 exactly right. * /
72 void *type_info;
73
74 / * Virtual table pointers in objects point here. * /
75
76 / * Virtual function pointers. Like the vcall/vbase array, the
77 real length of this table depends on the class hierarchy. * /
78 void (*virtual_functions[0]) ();
79
80 };
81
82 The catch, of course, is that the exact layout of this table
83 depends on the ABI --- word size, endianness, alignment, etc. So
84 the GDB type object is actually a per-architecture kind of thing.
85
86 vtable_type_gdbarch_data is a gdbarch per-architecture data pointer
87 which refers to the struct type * for this structure, laid out
88 appropriately for the architecture. */
b27b8843 89static struct gdbarch_data *vtable_type_gdbarch_data;
7ed49443
JB
90
91
92/* Human-readable names for the numbers of the fields above. */
93enum {
94 vtable_field_vcall_and_vbase_offsets,
95 vtable_field_offset_to_top,
96 vtable_field_type_info,
97 vtable_field_virtual_functions
98};
99
100
101/* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable',
102 described above, laid out appropriately for ARCH.
103
104 We use this function as the gdbarch per-architecture data
9970f04b 105 initialization function. */
7ed49443
JB
106static void *
107build_gdb_vtable_type (struct gdbarch *arch)
108{
109 struct type *t;
110 struct field *field_list, *field;
111 int offset;
112
113 struct type *void_ptr_type
fde6c819 114 = builtin_type (arch)->builtin_data_ptr;
7ed49443 115 struct type *ptr_to_void_fn_type
fde6c819 116 = builtin_type (arch)->builtin_func_ptr;
7ed49443
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117
118 /* ARCH can't give us the true ptrdiff_t type, so we guess. */
119 struct type *ptrdiff_type
e9bb382b 120 = arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t");
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JB
121
122 /* We assume no padding is necessary, since GDB doesn't know
123 anything about alignment at the moment. If this assumption bites
124 us, we should add a gdbarch method which, given a type, returns
125 the alignment that type requires, and then use that here. */
126
127 /* Build the field list. */
128 field_list = xmalloc (sizeof (struct field [4]));
129 memset (field_list, 0, sizeof (struct field [4]));
130 field = &field_list[0];
131 offset = 0;
132
133 /* ptrdiff_t vcall_and_vbase_offsets[0]; */
134 FIELD_NAME (*field) = "vcall_and_vbase_offsets";
e3506a9f 135 FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1);
f41f5e61 136 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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JB
137 offset += TYPE_LENGTH (FIELD_TYPE (*field));
138 field++;
139
140 /* ptrdiff_t offset_to_top; */
141 FIELD_NAME (*field) = "offset_to_top";
142 FIELD_TYPE (*field) = ptrdiff_type;
f41f5e61 143 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
7ed49443
JB
144 offset += TYPE_LENGTH (FIELD_TYPE (*field));
145 field++;
146
147 /* void *type_info; */
148 FIELD_NAME (*field) = "type_info";
149 FIELD_TYPE (*field) = void_ptr_type;
f41f5e61 150 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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JB
151 offset += TYPE_LENGTH (FIELD_TYPE (*field));
152 field++;
153
154 /* void (*virtual_functions[0]) (); */
155 FIELD_NAME (*field) = "virtual_functions";
e3506a9f 156 FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1);
f41f5e61 157 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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JB
158 offset += TYPE_LENGTH (FIELD_TYPE (*field));
159 field++;
160
161 /* We assumed in the allocation above that there were four fields. */
3d499020 162 gdb_assert (field == (field_list + 4));
7ed49443 163
e9bb382b 164 t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
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JB
165 TYPE_NFIELDS (t) = field - field_list;
166 TYPE_FIELDS (t) = field_list;
167 TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable";
e9bb382b 168 INIT_CPLUS_SPECIFIC (t);
7ed49443 169
706d0883 170 return make_type_with_address_space (t, TYPE_INSTANCE_FLAG_CODE_SPACE);
7ed49443
JB
171}
172
173
ed09d7da
KB
174/* Return the ptrdiff_t type used in the vtable type. */
175static struct type *
176vtable_ptrdiff_type (struct gdbarch *gdbarch)
177{
178 struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
179
180 /* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */
181 return TYPE_FIELD_TYPE (vtable_type, vtable_field_offset_to_top);
182}
183
7ed49443
JB
184/* Return the offset from the start of the imaginary `struct
185 gdb_gnu_v3_abi_vtable' object to the vtable's "address point"
186 (i.e., where objects' virtual table pointers point). */
187static int
ad4820ab 188vtable_address_point_offset (struct gdbarch *gdbarch)
7ed49443 189{
ad4820ab 190 struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
7ed49443
JB
191
192 return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions)
193 / TARGET_CHAR_BIT);
194}
195
196
d48cc9dd
DJ
197/* Determine whether structure TYPE is a dynamic class. Cache the
198 result. */
199
200static int
201gnuv3_dynamic_class (struct type *type)
202{
203 int fieldnum, fieldelem;
204
f168693b 205 type = check_typedef (type);
5f4ce105
DE
206 gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT
207 || TYPE_CODE (type) == TYPE_CODE_UNION);
208
209 if (TYPE_CODE (type) == TYPE_CODE_UNION)
210 return 0;
211
d48cc9dd
DJ
212 if (TYPE_CPLUS_DYNAMIC (type))
213 return TYPE_CPLUS_DYNAMIC (type) == 1;
214
215 ALLOCATE_CPLUS_STRUCT_TYPE (type);
216
217 for (fieldnum = 0; fieldnum < TYPE_N_BASECLASSES (type); fieldnum++)
218 if (BASETYPE_VIA_VIRTUAL (type, fieldnum)
219 || gnuv3_dynamic_class (TYPE_FIELD_TYPE (type, fieldnum)))
220 {
221 TYPE_CPLUS_DYNAMIC (type) = 1;
222 return 1;
223 }
224
225 for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
226 for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
227 fieldelem++)
228 {
229 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, fieldnum);
230
231 if (TYPE_FN_FIELD_VIRTUAL_P (f, fieldelem))
232 {
233 TYPE_CPLUS_DYNAMIC (type) = 1;
234 return 1;
235 }
236 }
237
238 TYPE_CPLUS_DYNAMIC (type) = -1;
239 return 0;
240}
241
242/* Find the vtable for a value of CONTAINER_TYPE located at
243 CONTAINER_ADDR. Return a value of the correct vtable type for this
244 architecture, or NULL if CONTAINER does not have a vtable. */
245
246static struct value *
247gnuv3_get_vtable (struct gdbarch *gdbarch,
248 struct type *container_type, CORE_ADDR container_addr)
249{
250 struct type *vtable_type = gdbarch_data (gdbarch,
251 vtable_type_gdbarch_data);
252 struct type *vtable_pointer_type;
253 struct value *vtable_pointer;
254 CORE_ADDR vtable_address;
255
f168693b 256 container_type = check_typedef (container_type);
5f4ce105
DE
257 gdb_assert (TYPE_CODE (container_type) == TYPE_CODE_STRUCT);
258
d48cc9dd
DJ
259 /* If this type does not have a virtual table, don't read the first
260 field. */
5f4ce105 261 if (!gnuv3_dynamic_class (container_type))
d48cc9dd
DJ
262 return NULL;
263
264 /* We do not consult the debug information to find the virtual table.
265 The ABI specifies that it is always at offset zero in any class,
266 and debug information may not represent it.
267
268 We avoid using value_contents on principle, because the object might
269 be large. */
270
271 /* Find the type "pointer to virtual table". */
272 vtable_pointer_type = lookup_pointer_type (vtable_type);
273
274 /* Load it from the start of the class. */
275 vtable_pointer = value_at (vtable_pointer_type, container_addr);
276 vtable_address = value_as_address (vtable_pointer);
277
278 /* Correct it to point at the start of the virtual table, rather
279 than the address point. */
280 return value_at_lazy (vtable_type,
0963b4bd
MS
281 vtable_address
282 - vtable_address_point_offset (gdbarch));
d48cc9dd
DJ
283}
284
285
7ed49443
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286static struct type *
287gnuv3_rtti_type (struct value *value,
288 int *full_p, int *top_p, int *using_enc_p)
289{
ad4820ab 290 struct gdbarch *gdbarch;
df407dfe 291 struct type *values_type = check_typedef (value_type (value));
7ed49443
JB
292 struct value *vtable;
293 struct minimal_symbol *vtable_symbol;
294 const char *vtable_symbol_name;
295 const char *class_name;
7ed49443
JB
296 struct type *run_time_type;
297 LONGEST offset_to_top;
8de20a37 298 char *atsign;
7ed49443
JB
299
300 /* We only have RTTI for class objects. */
4753d33b 301 if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
7ed49443
JB
302 return NULL;
303
eb2a6f42
TT
304 /* Java doesn't have RTTI following the C++ ABI. */
305 if (TYPE_CPLUS_REALLY_JAVA (values_type))
306 return NULL;
307
ad4820ab 308 /* Determine architecture. */
50810684 309 gdbarch = get_type_arch (values_type);
7ed49443 310
21cfb3b6
DJ
311 if (using_enc_p)
312 *using_enc_p = 0;
313
5f4ce105 314 vtable = gnuv3_get_vtable (gdbarch, values_type,
d48cc9dd
DJ
315 value_as_address (value_addr (value)));
316 if (vtable == NULL)
317 return NULL;
318
7ed49443
JB
319 /* Find the linker symbol for this vtable. */
320 vtable_symbol
42ae5230 321 = lookup_minimal_symbol_by_pc (value_address (vtable)
7cbd4a93 322 + value_embedded_offset (vtable)).minsym;
7ed49443
JB
323 if (! vtable_symbol)
324 return NULL;
325
326 /* The symbol's demangled name should be something like "vtable for
327 CLASS", where CLASS is the name of the run-time type of VALUE.
328 If we didn't like this approach, we could instead look in the
329 type_info object itself to get the class name. But this way
330 should work just as well, and doesn't read target memory. */
efd66ac6 331 vtable_symbol_name = MSYMBOL_DEMANGLED_NAME (vtable_symbol);
98081e55 332 if (vtable_symbol_name == NULL
61012eef 333 || !startswith (vtable_symbol_name, "vtable for "))
f773fdbb 334 {
8a3fe4f8 335 warning (_("can't find linker symbol for virtual table for `%s' value"),
0a07729b 336 TYPE_SAFE_NAME (values_type));
f773fdbb 337 if (vtable_symbol_name)
8a3fe4f8 338 warning (_(" found `%s' instead"), vtable_symbol_name);
f773fdbb
JM
339 return NULL;
340 }
7ed49443
JB
341 class_name = vtable_symbol_name + 11;
342
8de20a37
TT
343 /* Strip off @plt and version suffixes. */
344 atsign = strchr (class_name, '@');
345 if (atsign != NULL)
346 {
347 char *copy;
348
349 copy = alloca (atsign - class_name + 1);
350 memcpy (copy, class_name, atsign - class_name);
351 copy[atsign - class_name] = '\0';
352 class_name = copy;
353 }
354
7ed49443 355 /* Try to look up the class name as a type name. */
0963b4bd 356 /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
362ff856
MC
357 run_time_type = cp_lookup_rtti_type (class_name, NULL);
358 if (run_time_type == NULL)
359 return NULL;
7ed49443
JB
360
361 /* Get the offset from VALUE to the top of the complete object.
362 NOTE: this is the reverse of the meaning of *TOP_P. */
363 offset_to_top
364 = value_as_long (value_field (vtable, vtable_field_offset_to_top));
365
366 if (full_p)
13c3b5f5 367 *full_p = (- offset_to_top == value_embedded_offset (value)
4754a64e 368 && (TYPE_LENGTH (value_enclosing_type (value))
7ed49443
JB
369 >= TYPE_LENGTH (run_time_type)));
370 if (top_p)
371 *top_p = - offset_to_top;
7ed49443
JB
372 return run_time_type;
373}
374
0d5de010
DJ
375/* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
376 function, of type FNTYPE. */
7ed49443 377
0d5de010 378static struct value *
ad4820ab
UW
379gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container,
380 struct type *fntype, int vtable_index)
0d5de010 381{
d48cc9dd
DJ
382 struct value *vtable, *vfn;
383
384 /* Every class with virtual functions must have a vtable. */
385 vtable = gnuv3_get_vtable (gdbarch, value_type (container),
386 value_as_address (value_addr (container)));
387 gdb_assert (vtable != NULL);
7ed49443
JB
388
389 /* Fetch the appropriate function pointer from the vtable. */
390 vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions),
2497b498 391 vtable_index);
7ed49443 392
0d5de010
DJ
393 /* If this architecture uses function descriptors directly in the vtable,
394 then the address of the vtable entry is actually a "function pointer"
395 (i.e. points to the descriptor). We don't need to scale the index
396 by the size of a function descriptor; GCC does that before outputing
397 debug information. */
ad4820ab 398 if (gdbarch_vtable_function_descriptors (gdbarch))
0d5de010 399 vfn = value_addr (vfn);
7ed49443 400
0d5de010
DJ
401 /* Cast the function pointer to the appropriate type. */
402 vfn = value_cast (lookup_pointer_type (fntype), vfn);
76b79d6e 403
7ed49443
JB
404 return vfn;
405}
406
0d5de010
DJ
407/* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h
408 for a description of the arguments. */
409
410static struct value *
411gnuv3_virtual_fn_field (struct value **value_p,
412 struct fn_field *f, int j,
413 struct type *vfn_base, int offset)
414{
415 struct type *values_type = check_typedef (value_type (*value_p));
ad4820ab 416 struct gdbarch *gdbarch;
0d5de010
DJ
417
418 /* Some simple sanity checks. */
4753d33b 419 if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
0d5de010
DJ
420 error (_("Only classes can have virtual functions."));
421
ad4820ab 422 /* Determine architecture. */
50810684 423 gdbarch = get_type_arch (values_type);
ad4820ab 424
0d5de010
DJ
425 /* Cast our value to the base class which defines this virtual
426 function. This takes care of any necessary `this'
427 adjustments. */
428 if (vfn_base != values_type)
429 *value_p = value_cast (vfn_base, *value_p);
430
ad4820ab 431 return gnuv3_get_virtual_fn (gdbarch, *value_p, TYPE_FN_FIELD_TYPE (f, j),
0d5de010
DJ
432 TYPE_FN_FIELD_VOFFSET (f, j));
433}
434
1514d34e
DJ
435/* Compute the offset of the baseclass which is
436 the INDEXth baseclass of class TYPE,
437 for value at VALADDR (in host) at ADDRESS (in target).
438 The result is the offset of the baseclass value relative
439 to (the address of)(ARG) + OFFSET.
440
0963b4bd
MS
441 -1 is returned on error. */
442
b9362cc7 443static int
8af8e3bc
PA
444gnuv3_baseclass_offset (struct type *type, int index,
445 const bfd_byte *valaddr, int embedded_offset,
446 CORE_ADDR address, const struct value *val)
1514d34e 447{
ad4820ab 448 struct gdbarch *gdbarch;
ad4820ab 449 struct type *ptr_type;
79d5b63a 450 struct value *vtable;
2497b498 451 struct value *vbase_array;
1514d34e 452 long int cur_base_offset, base_offset;
1514d34e 453
ad4820ab 454 /* Determine architecture. */
50810684 455 gdbarch = get_type_arch (type);
ad4820ab
UW
456 ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
457
1514d34e 458 /* If it isn't a virtual base, this is easy. The offset is in the
b1af9e97
TT
459 type definition. Likewise for Java, which doesn't really have
460 virtual inheritance in the C++ sense. */
461 if (!BASETYPE_VIA_VIRTUAL (type, index) || TYPE_CPLUS_REALLY_JAVA (type))
1514d34e
DJ
462 return TYPE_BASECLASS_BITPOS (type, index) / 8;
463
464 /* To access a virtual base, we need to use the vbase offset stored in
465 our vtable. Recent GCC versions provide this information. If it isn't
466 available, we could get what we needed from RTTI, or from drawing the
467 complete inheritance graph based on the debug info. Neither is
468 worthwhile. */
469 cur_base_offset = TYPE_BASECLASS_BITPOS (type, index) / 8;
ad4820ab 470 if (cur_base_offset >= - vtable_address_point_offset (gdbarch))
8a3fe4f8 471 error (_("Expected a negative vbase offset (old compiler?)"));
1514d34e 472
ad4820ab
UW
473 cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch);
474 if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0)
8a3fe4f8 475 error (_("Misaligned vbase offset."));
ad4820ab 476 cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type));
1514d34e 477
8af8e3bc 478 vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset);
d48cc9dd 479 gdb_assert (vtable != NULL);
1514d34e 480 vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets);
2497b498 481 base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset));
1514d34e
DJ
482 return base_offset;
483}
7ed49443 484
0d5de010
DJ
485/* Locate a virtual method in DOMAIN or its non-virtual base classes
486 which has virtual table index VOFFSET. The method has an associated
487 "this" adjustment of ADJUSTMENT bytes. */
488
2c0b251b 489static const char *
0d5de010
DJ
490gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset,
491 LONGEST adjustment)
492{
493 int i;
0d5de010
DJ
494
495 /* Search this class first. */
0d5de010
DJ
496 if (adjustment == 0)
497 {
498 int len;
499
500 len = TYPE_NFN_FIELDS (domain);
501 for (i = 0; i < len; i++)
502 {
503 int len2, j;
504 struct fn_field *f;
505
506 f = TYPE_FN_FIELDLIST1 (domain, i);
507 len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
508
509 check_stub_method_group (domain, i);
510 for (j = 0; j < len2; j++)
511 if (TYPE_FN_FIELD_VOFFSET (f, j) == voffset)
512 return TYPE_FN_FIELD_PHYSNAME (f, j);
513 }
514 }
515
516 /* Next search non-virtual bases. If it's in a virtual base,
517 we're out of luck. */
518 for (i = 0; i < TYPE_N_BASECLASSES (domain); i++)
519 {
520 int pos;
521 struct type *basetype;
522
523 if (BASETYPE_VIA_VIRTUAL (domain, i))
524 continue;
525
526 pos = TYPE_BASECLASS_BITPOS (domain, i) / 8;
527 basetype = TYPE_FIELD_TYPE (domain, i);
528 /* Recurse with a modified adjustment. We don't need to adjust
529 voffset. */
530 if (adjustment >= pos && adjustment < pos + TYPE_LENGTH (basetype))
531 return gnuv3_find_method_in (basetype, voffset, adjustment - pos);
532 }
533
534 return NULL;
535}
536
fead6908
UW
537/* Decode GNU v3 method pointer. */
538
539static int
ad4820ab
UW
540gnuv3_decode_method_ptr (struct gdbarch *gdbarch,
541 const gdb_byte *contents,
fead6908
UW
542 CORE_ADDR *value_p,
543 LONGEST *adjustment_p)
544{
ad4820ab 545 struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr;
ed09d7da 546 struct type *offset_type = vtable_ptrdiff_type (gdbarch);
e17a4113 547 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
fead6908
UW
548 CORE_ADDR ptr_value;
549 LONGEST voffset, adjustment;
550 int vbit;
551
552 /* Extract the pointer to member. The first element is either a pointer
553 or a vtable offset. For pointers, we need to use extract_typed_address
554 to allow the back-end to convert the pointer to a GDB address -- but
555 vtable offsets we must handle as integers. At this point, we do not
556 yet know which case we have, so we extract the value under both
557 interpretations and choose the right one later on. */
558 ptr_value = extract_typed_address (contents, funcptr_type);
e17a4113
UW
559 voffset = extract_signed_integer (contents,
560 TYPE_LENGTH (funcptr_type), byte_order);
fead6908 561 contents += TYPE_LENGTH (funcptr_type);
e17a4113
UW
562 adjustment = extract_signed_integer (contents,
563 TYPE_LENGTH (offset_type), byte_order);
fead6908 564
ad4820ab 565 if (!gdbarch_vbit_in_delta (gdbarch))
fead6908
UW
566 {
567 vbit = voffset & 1;
568 voffset = voffset ^ vbit;
569 }
570 else
571 {
572 vbit = adjustment & 1;
573 adjustment = adjustment >> 1;
574 }
575
576 *value_p = vbit? voffset : ptr_value;
577 *adjustment_p = adjustment;
578 return vbit;
579}
580
0d5de010
DJ
581/* GNU v3 implementation of cplus_print_method_ptr. */
582
583static void
584gnuv3_print_method_ptr (const gdb_byte *contents,
585 struct type *type,
586 struct ui_file *stream)
587{
09e2d7c7
DE
588 struct type *self_type = TYPE_SELF_TYPE (type);
589 struct gdbarch *gdbarch = get_type_arch (self_type);
0d5de010
DJ
590 CORE_ADDR ptr_value;
591 LONGEST adjustment;
0d5de010
DJ
592 int vbit;
593
0d5de010 594 /* Extract the pointer to member. */
ad4820ab 595 vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
0d5de010
DJ
596
597 /* Check for NULL. */
598 if (ptr_value == 0 && vbit == 0)
599 {
600 fprintf_filtered (stream, "NULL");
601 return;
602 }
603
604 /* Search for a virtual method. */
605 if (vbit)
606 {
607 CORE_ADDR voffset;
608 const char *physname;
609
610 /* It's a virtual table offset, maybe in this class. Search
611 for a field with the correct vtable offset. First convert it
612 to an index, as used in TYPE_FN_FIELD_VOFFSET. */
ed09d7da 613 voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
0d5de010 614
09e2d7c7 615 physname = gnuv3_find_method_in (self_type, voffset, adjustment);
0d5de010
DJ
616
617 /* If we found a method, print that. We don't bother to disambiguate
618 possible paths to the method based on the adjustment. */
619 if (physname)
620 {
8de20a37
TT
621 char *demangled_name = gdb_demangle (physname,
622 DMGL_ANSI | DMGL_PARAMS);
d8734c88 623
94af9270
KS
624 fprintf_filtered (stream, "&virtual ");
625 if (demangled_name == NULL)
626 fputs_filtered (physname, stream);
627 else
0d5de010 628 {
0d5de010
DJ
629 fputs_filtered (demangled_name, stream);
630 xfree (demangled_name);
0d5de010 631 }
94af9270 632 return;
0d5de010
DJ
633 }
634 }
94af9270
KS
635 else if (ptr_value != 0)
636 {
637 /* Found a non-virtual function: print out the type. */
638 fputs_filtered ("(", stream);
79d43c61 639 c_print_type (type, "", stream, -1, 0, &type_print_raw_options);
94af9270
KS
640 fputs_filtered (") ", stream);
641 }
0d5de010
DJ
642
643 /* We didn't find it; print the raw data. */
644 if (vbit)
645 {
646 fprintf_filtered (stream, "&virtual table offset ");
647 print_longest (stream, 'd', 1, ptr_value);
648 }
649 else
edf0c1b7
TT
650 {
651 struct value_print_options opts;
652
653 get_user_print_options (&opts);
654 print_address_demangle (&opts, gdbarch, ptr_value, stream, demangle);
655 }
0d5de010
DJ
656
657 if (adjustment)
658 {
659 fprintf_filtered (stream, ", this adjustment ");
660 print_longest (stream, 'd', 1, adjustment);
661 }
662}
663
664/* GNU v3 implementation of cplus_method_ptr_size. */
665
666static int
ad4820ab 667gnuv3_method_ptr_size (struct type *type)
0d5de010 668{
561d3825 669 struct gdbarch *gdbarch = get_type_arch (type);
d8734c88 670
ad4820ab 671 return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
0d5de010
DJ
672}
673
674/* GNU v3 implementation of cplus_make_method_ptr. */
675
676static void
ad4820ab
UW
677gnuv3_make_method_ptr (struct type *type, gdb_byte *contents,
678 CORE_ADDR value, int is_virtual)
0d5de010 679{
561d3825 680 struct gdbarch *gdbarch = get_type_arch (type);
ad4820ab 681 int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
e17a4113 682 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
0d5de010
DJ
683
684 /* FIXME drow/2006-12-24: The adjustment of "this" is currently
685 always zero, since the method pointer is of the correct type.
686 But if the method pointer came from a base class, this is
687 incorrect - it should be the offset to the base. The best
688 fix might be to create the pointer to member pointing at the
689 base class and cast it to the derived class, but that requires
690 support for adjusting pointers to members when casting them -
691 not currently supported by GDB. */
692
ad4820ab 693 if (!gdbarch_vbit_in_delta (gdbarch))
0d5de010 694 {
e17a4113
UW
695 store_unsigned_integer (contents, size, byte_order, value | is_virtual);
696 store_unsigned_integer (contents + size, size, byte_order, 0);
0d5de010
DJ
697 }
698 else
699 {
e17a4113
UW
700 store_unsigned_integer (contents, size, byte_order, value);
701 store_unsigned_integer (contents + size, size, byte_order, is_virtual);
0d5de010
DJ
702 }
703}
704
705/* GNU v3 implementation of cplus_method_ptr_to_value. */
706
707static struct value *
708gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
709{
ad4820ab 710 struct gdbarch *gdbarch;
0d5de010
DJ
711 const gdb_byte *contents = value_contents (method_ptr);
712 CORE_ADDR ptr_value;
09e2d7c7 713 struct type *self_type, *final_type, *method_type;
0d5de010 714 LONGEST adjustment;
0d5de010
DJ
715 int vbit;
716
09e2d7c7
DE
717 self_type = TYPE_SELF_TYPE (check_typedef (value_type (method_ptr)));
718 final_type = lookup_pointer_type (self_type);
0d5de010
DJ
719
720 method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
721
fead6908 722 /* Extract the pointer to member. */
09e2d7c7 723 gdbarch = get_type_arch (self_type);
ad4820ab 724 vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
0d5de010
DJ
725
726 /* First convert THIS to match the containing type of the pointer to
727 member. This cast may adjust the value of THIS. */
728 *this_p = value_cast (final_type, *this_p);
729
730 /* Then apply whatever adjustment is necessary. This creates a somewhat
731 strange pointer: it claims to have type FINAL_TYPE, but in fact it
732 might not be a valid FINAL_TYPE. For instance, it might be a
733 base class of FINAL_TYPE. And if it's not the primary base class,
734 then printing it out as a FINAL_TYPE object would produce some pretty
735 garbage.
736
737 But we don't really know the type of the first argument in
738 METHOD_TYPE either, which is why this happens. We can't
739 dereference this later as a FINAL_TYPE, but once we arrive in the
740 called method we'll have debugging information for the type of
741 "this" - and that'll match the value we produce here.
742
743 You can provoke this case by casting a Base::* to a Derived::*, for
744 instance. */
ad4820ab 745 *this_p = value_cast (builtin_type (gdbarch)->builtin_data_ptr, *this_p);
2497b498 746 *this_p = value_ptradd (*this_p, adjustment);
0d5de010
DJ
747 *this_p = value_cast (final_type, *this_p);
748
749 if (vbit)
750 {
ad4820ab 751 LONGEST voffset;
d8734c88 752
ed09d7da 753 voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
ad4820ab
UW
754 return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p),
755 method_type, voffset);
0d5de010
DJ
756 }
757 else
758 return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
759}
760
c4aeac85
TT
761/* Objects of this type are stored in a hash table and a vector when
762 printing the vtables for a class. */
763
764struct value_and_voffset
765{
766 /* The value representing the object. */
767 struct value *value;
768
769 /* The maximum vtable offset we've found for any object at this
770 offset in the outermost object. */
771 int max_voffset;
772};
773
774typedef struct value_and_voffset *value_and_voffset_p;
775DEF_VEC_P (value_and_voffset_p);
776
777/* Hash function for value_and_voffset. */
778
779static hashval_t
780hash_value_and_voffset (const void *p)
781{
782 const struct value_and_voffset *o = p;
783
784 return value_address (o->value) + value_embedded_offset (o->value);
785}
786
787/* Equality function for value_and_voffset. */
788
789static int
790eq_value_and_voffset (const void *a, const void *b)
791{
792 const struct value_and_voffset *ova = a;
793 const struct value_and_voffset *ovb = b;
794
795 return (value_address (ova->value) + value_embedded_offset (ova->value)
796 == value_address (ovb->value) + value_embedded_offset (ovb->value));
797}
798
799/* qsort comparison function for value_and_voffset. */
800
801static int
802compare_value_and_voffset (const void *a, const void *b)
803{
804 const struct value_and_voffset * const *ova = a;
805 CORE_ADDR addra = (value_address ((*ova)->value)
806 + value_embedded_offset ((*ova)->value));
807 const struct value_and_voffset * const *ovb = b;
808 CORE_ADDR addrb = (value_address ((*ovb)->value)
809 + value_embedded_offset ((*ovb)->value));
810
811 if (addra < addrb)
812 return -1;
813 if (addra > addrb)
814 return 1;
815 return 0;
816}
817
818/* A helper function used when printing vtables. This determines the
819 key (most derived) sub-object at each address and also computes the
820 maximum vtable offset seen for the corresponding vtable. Updates
821 OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if
822 needed. VALUE is the object to examine. */
823
824static void
825compute_vtable_size (htab_t offset_hash,
826 VEC (value_and_voffset_p) **offset_vec,
827 struct value *value)
828{
829 int i;
830 struct type *type = check_typedef (value_type (value));
831 void **slot;
832 struct value_and_voffset search_vo, *current_vo;
c4aeac85 833
5f4ce105
DE
834 gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT);
835
c4aeac85
TT
836 /* If the object is not dynamic, then we are done; as it cannot have
837 dynamic base types either. */
838 if (!gnuv3_dynamic_class (type))
839 return;
840
841 /* Update the hash and the vec, if needed. */
842 search_vo.value = value;
843 slot = htab_find_slot (offset_hash, &search_vo, INSERT);
844 if (*slot)
845 current_vo = *slot;
846 else
847 {
848 current_vo = XNEW (struct value_and_voffset);
849 current_vo->value = value;
850 current_vo->max_voffset = -1;
851 *slot = current_vo;
852 VEC_safe_push (value_and_voffset_p, *offset_vec, current_vo);
853 }
854
855 /* Update the value_and_voffset object with the highest vtable
856 offset from this class. */
857 for (i = 0; i < TYPE_NFN_FIELDS (type); ++i)
858 {
859 int j;
860 struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, i);
861
862 for (j = 0; j < TYPE_FN_FIELDLIST_LENGTH (type, i); ++j)
863 {
864 if (TYPE_FN_FIELD_VIRTUAL_P (fn, j))
865 {
866 int voffset = TYPE_FN_FIELD_VOFFSET (fn, j);
867
868 if (voffset > current_vo->max_voffset)
869 current_vo->max_voffset = voffset;
870 }
871 }
872 }
873
874 /* Recurse into base classes. */
875 for (i = 0; i < TYPE_N_BASECLASSES (type); ++i)
876 compute_vtable_size (offset_hash, offset_vec, value_field (value, i));
877}
878
879/* Helper for gnuv3_print_vtable that prints a single vtable. */
880
881static void
882print_one_vtable (struct gdbarch *gdbarch, struct value *value,
883 int max_voffset,
884 struct value_print_options *opts)
885{
886 int i;
887 struct type *type = check_typedef (value_type (value));
888 struct value *vtable;
889 CORE_ADDR vt_addr;
890
891 vtable = gnuv3_get_vtable (gdbarch, type,
892 value_address (value)
893 + value_embedded_offset (value));
894 vt_addr = value_address (value_field (vtable,
895 vtable_field_virtual_functions));
896
897 printf_filtered (_("vtable for '%s' @ %s (subobject @ %s):\n"),
898 TYPE_SAFE_NAME (type),
899 paddress (gdbarch, vt_addr),
900 paddress (gdbarch, (value_address (value)
901 + value_embedded_offset (value))));
902
903 for (i = 0; i <= max_voffset; ++i)
904 {
cafe75b0
JK
905 /* Initialize it just to avoid a GCC false warning. */
906 CORE_ADDR addr = 0;
492d29ea 907 int got_error = 0;
c4aeac85 908 struct value *vfn;
c4aeac85
TT
909
910 printf_filtered ("[%d]: ", i);
911
912 vfn = value_subscript (value_field (vtable,
913 vtable_field_virtual_functions),
914 i);
915
916 if (gdbarch_vtable_function_descriptors (gdbarch))
917 vfn = value_addr (vfn);
918
492d29ea 919 TRY
c4aeac85
TT
920 {
921 addr = value_as_address (vfn);
922 }
492d29ea
PA
923 CATCH (ex, RETURN_MASK_ERROR)
924 {
925 printf_filtered (_("<error: %s>"), ex.message);
926 got_error = 1;
927 }
928 END_CATCH
929
930 if (!got_error)
edf0c1b7 931 print_function_pointer_address (opts, gdbarch, addr, gdb_stdout);
c4aeac85
TT
932 printf_filtered ("\n");
933 }
934}
935
936/* Implementation of the print_vtable method. */
937
938static void
939gnuv3_print_vtable (struct value *value)
940{
941 struct gdbarch *gdbarch;
942 struct type *type;
943 struct value *vtable;
944 struct value_print_options opts;
945 htab_t offset_hash;
946 struct cleanup *cleanup;
5ff5c7b4 947 VEC (value_and_voffset_p) *result_vec = NULL;
c4aeac85
TT
948 struct value_and_voffset *iter;
949 int i, count;
950
951 value = coerce_ref (value);
952 type = check_typedef (value_type (value));
953 if (TYPE_CODE (type) == TYPE_CODE_PTR)
954 {
955 value = value_ind (value);
956 type = check_typedef (value_type (value));
957 }
958
959 get_user_print_options (&opts);
960
961 /* Respect 'set print object'. */
962 if (opts.objectprint)
963 {
964 value = value_full_object (value, NULL, 0, 0, 0);
965 type = check_typedef (value_type (value));
966 }
967
968 gdbarch = get_type_arch (type);
5f4ce105
DE
969
970 vtable = NULL;
971 if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
972 vtable = gnuv3_get_vtable (gdbarch, type,
973 value_as_address (value_addr (value)));
c4aeac85
TT
974
975 if (!vtable)
976 {
977 printf_filtered (_("This object does not have a virtual function table\n"));
978 return;
979 }
980
981 offset_hash = htab_create_alloc (1, hash_value_and_voffset,
982 eq_value_and_voffset,
983 xfree, xcalloc, xfree);
984 cleanup = make_cleanup_htab_delete (offset_hash);
985 make_cleanup (VEC_cleanup (value_and_voffset_p), &result_vec);
986
987 compute_vtable_size (offset_hash, &result_vec, value);
988
989 qsort (VEC_address (value_and_voffset_p, result_vec),
990 VEC_length (value_and_voffset_p, result_vec),
991 sizeof (value_and_voffset_p),
992 compare_value_and_voffset);
993
994 count = 0;
995 for (i = 0; VEC_iterate (value_and_voffset_p, result_vec, i, iter); ++i)
996 {
997 if (iter->max_voffset >= 0)
998 {
999 if (count > 0)
1000 printf_filtered ("\n");
1001 print_one_vtable (gdbarch, iter->value, iter->max_voffset, &opts);
1002 ++count;
1003 }
1004 }
1005
1006 do_cleanups (cleanup);
1007}
1008
6e72ca20
TT
1009/* Return a GDB type representing `struct std::type_info', laid out
1010 appropriately for ARCH.
1011
1012 We use this function as the gdbarch per-architecture data
1013 initialization function. */
1014
1015static void *
1016build_std_type_info_type (struct gdbarch *arch)
1017{
1018 struct type *t;
1019 struct field *field_list, *field;
1020 int offset;
1021 struct type *void_ptr_type
1022 = builtin_type (arch)->builtin_data_ptr;
1023 struct type *char_type
1024 = builtin_type (arch)->builtin_char;
1025 struct type *char_ptr_type
1026 = make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL);
1027
1028 field_list = xmalloc (sizeof (struct field [2]));
1029 memset (field_list, 0, sizeof (struct field [2]));
1030 field = &field_list[0];
1031 offset = 0;
1032
1033 /* The vtable. */
1034 FIELD_NAME (*field) = "_vptr.type_info";
1035 FIELD_TYPE (*field) = void_ptr_type;
1036 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
1037 offset += TYPE_LENGTH (FIELD_TYPE (*field));
1038 field++;
1039
1040 /* The name. */
1041 FIELD_NAME (*field) = "__name";
1042 FIELD_TYPE (*field) = char_ptr_type;
1043 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
1044 offset += TYPE_LENGTH (FIELD_TYPE (*field));
1045 field++;
1046
1047 gdb_assert (field == (field_list + 2));
1048
1049 t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
1050 TYPE_NFIELDS (t) = field - field_list;
1051 TYPE_FIELDS (t) = field_list;
1052 TYPE_TAG_NAME (t) = "gdb_gnu_v3_type_info";
1053 INIT_CPLUS_SPECIFIC (t);
1054
1055 return t;
1056}
1057
1058/* Implement the 'get_typeid_type' method. */
1059
1060static struct type *
1061gnuv3_get_typeid_type (struct gdbarch *gdbarch)
1062{
1063 struct symbol *typeinfo;
1064 struct type *typeinfo_type;
1065
d12307c1
PMR
1066 typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN,
1067 NULL).symbol;
6e72ca20
TT
1068 if (typeinfo == NULL)
1069 typeinfo_type = gdbarch_data (gdbarch, std_type_info_gdbarch_data);
1070 else
1071 typeinfo_type = SYMBOL_TYPE (typeinfo);
1072
1073 return typeinfo_type;
1074}
1075
1076/* Implement the 'get_typeid' method. */
1077
1078static struct value *
1079gnuv3_get_typeid (struct value *value)
1080{
1081 struct type *typeinfo_type;
1082 struct type *type;
1083 struct gdbarch *gdbarch;
1084 struct cleanup *cleanup;
1085 struct value *result;
fe978cb0 1086 char *type_name, *canonical;
6e72ca20
TT
1087
1088 /* We have to handle values a bit trickily here, to allow this code
1089 to work properly with non_lvalue values that are really just
1090 disguised types. */
1091 if (value_lval_const (value) == lval_memory)
1092 value = coerce_ref (value);
1093
1094 type = check_typedef (value_type (value));
1095
1096 /* In the non_lvalue case, a reference might have slipped through
1097 here. */
1098 if (TYPE_CODE (type) == TYPE_CODE_REF)
1099 type = check_typedef (TYPE_TARGET_TYPE (type));
1100
1101 /* Ignore top-level cv-qualifiers. */
1102 type = make_cv_type (0, 0, type, NULL);
1103 gdbarch = get_type_arch (type);
1104
fe978cb0
PA
1105 type_name = type_to_string (type);
1106 if (type_name == NULL)
6e72ca20 1107 error (_("cannot find typeinfo for unnamed type"));
fe978cb0 1108 cleanup = make_cleanup (xfree, type_name);
6e72ca20
TT
1109
1110 /* We need to canonicalize the type name here, because we do lookups
1111 using the demangled name, and so we must match the format it
1112 uses. E.g., GDB tends to use "const char *" as a type name, but
1113 the demangler uses "char const *". */
fe978cb0 1114 canonical = cp_canonicalize_string (type_name);
6e72ca20
TT
1115 if (canonical != NULL)
1116 {
1117 make_cleanup (xfree, canonical);
fe978cb0 1118 type_name = canonical;
6e72ca20
TT
1119 }
1120
1121 typeinfo_type = gnuv3_get_typeid_type (gdbarch);
1122
1123 /* We check for lval_memory because in the "typeid (type-id)" case,
1124 the type is passed via a not_lval value object. */
4753d33b 1125 if (TYPE_CODE (type) == TYPE_CODE_STRUCT
6e72ca20
TT
1126 && value_lval_const (value) == lval_memory
1127 && gnuv3_dynamic_class (type))
1128 {
1129 struct value *vtable, *typeinfo_value;
1130 CORE_ADDR address = value_address (value) + value_embedded_offset (value);
1131
1132 vtable = gnuv3_get_vtable (gdbarch, type, address);
1133 if (vtable == NULL)
fe978cb0 1134 error (_("cannot find typeinfo for object of type '%s'"), type_name);
6e72ca20
TT
1135 typeinfo_value = value_field (vtable, vtable_field_type_info);
1136 result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL),
1137 typeinfo_value));
1138 }
1139 else
1140 {
1141 char *sym_name;
3b7344d5 1142 struct bound_minimal_symbol minsym;
6e72ca20 1143
fe978cb0 1144 sym_name = concat ("typeinfo for ", type_name, (char *) NULL);
6e72ca20
TT
1145 make_cleanup (xfree, sym_name);
1146 minsym = lookup_minimal_symbol (sym_name, NULL, NULL);
1147
3b7344d5 1148 if (minsym.minsym == NULL)
fe978cb0 1149 error (_("could not find typeinfo symbol for '%s'"), type_name);
6e72ca20 1150
77e371c0 1151 result = value_at_lazy (typeinfo_type, BMSYMBOL_VALUE_ADDRESS (minsym));
6e72ca20
TT
1152 }
1153
1154 do_cleanups (cleanup);
1155 return result;
1156}
1157
cc16e6c9 1158/* Implement the 'get_typename_from_type_info' method. */
72f1fe8a
TT
1159
1160static char *
1161gnuv3_get_typename_from_type_info (struct value *type_info_ptr)
1162{
1163 struct gdbarch *gdbarch = get_type_arch (value_type (type_info_ptr));
1164 struct bound_minimal_symbol typeinfo_sym;
1165 CORE_ADDR addr;
1166 const char *symname;
1167 const char *class_name;
1168 const char *atsign;
1169
1170 addr = value_as_address (type_info_ptr);
1171 typeinfo_sym = lookup_minimal_symbol_by_pc (addr);
1172 if (typeinfo_sym.minsym == NULL)
1173 error (_("could not find minimal symbol for typeinfo address %s"),
1174 paddress (gdbarch, addr));
1175
1176#define TYPEINFO_PREFIX "typeinfo for "
1177#define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1)
efd66ac6 1178 symname = MSYMBOL_DEMANGLED_NAME (typeinfo_sym.minsym);
72f1fe8a
TT
1179 if (symname == NULL || strncmp (symname, TYPEINFO_PREFIX,
1180 TYPEINFO_PREFIX_LEN))
1181 error (_("typeinfo symbol '%s' has unexpected name"),
efd66ac6 1182 MSYMBOL_LINKAGE_NAME (typeinfo_sym.minsym));
72f1fe8a
TT
1183 class_name = symname + TYPEINFO_PREFIX_LEN;
1184
1185 /* Strip off @plt and version suffixes. */
1186 atsign = strchr (class_name, '@');
1187 if (atsign != NULL)
1188 return savestring (class_name, atsign - class_name);
1189 return xstrdup (class_name);
1190}
1191
1192/* Implement the 'get_type_from_type_info' method. */
1193
1194static struct type *
1195gnuv3_get_type_from_type_info (struct value *type_info_ptr)
1196{
fe978cb0 1197 char *type_name;
72f1fe8a
TT
1198 struct cleanup *cleanup;
1199 struct value *type_val;
1200 struct expression *expr;
1201 struct type *result;
1202
fe978cb0
PA
1203 type_name = gnuv3_get_typename_from_type_info (type_info_ptr);
1204 cleanup = make_cleanup (xfree, type_name);
72f1fe8a
TT
1205
1206 /* We have to parse the type name, since in general there is not a
1207 symbol for a type. This is somewhat bogus since there may be a
1208 mis-parse. Another approach might be to re-use the demangler's
1209 internal form to reconstruct the type somehow. */
1210
fe978cb0 1211 expr = parse_expression (type_name);
72f1fe8a
TT
1212 make_cleanup (xfree, expr);
1213
1214 type_val = evaluate_type (expr);
1215 result = value_type (type_val);
1216
1217 do_cleanups (cleanup);
1218 return result;
1219}
1220
b18be20d
DJ
1221/* Determine if we are currently in a C++ thunk. If so, get the address
1222 of the routine we are thunking to and continue to there instead. */
1223
1224static CORE_ADDR
52f729a7 1225gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc)
b18be20d 1226{
a513d1e8 1227 CORE_ADDR real_stop_pc, method_stop_pc, func_addr;
9970f04b 1228 struct gdbarch *gdbarch = get_frame_arch (frame);
3b7344d5 1229 struct bound_minimal_symbol thunk_sym, fn_sym;
b18be20d 1230 struct obj_section *section;
0d5cff50 1231 const char *thunk_name, *fn_name;
b18be20d 1232
9970f04b 1233 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
b18be20d
DJ
1234 if (real_stop_pc == 0)
1235 real_stop_pc = stop_pc;
1236
1237 /* Find the linker symbol for this potential thunk. */
3b7344d5 1238 thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc);
b18be20d 1239 section = find_pc_section (real_stop_pc);
3b7344d5 1240 if (thunk_sym.minsym == NULL || section == NULL)
b18be20d
DJ
1241 return 0;
1242
1243 /* The symbol's demangled name should be something like "virtual
1244 thunk to FUNCTION", where FUNCTION is the name of the function
1245 being thunked to. */
3b7344d5 1246 thunk_name = MSYMBOL_DEMANGLED_NAME (thunk_sym.minsym);
b18be20d
DJ
1247 if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL)
1248 return 0;
1249
1250 fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to ");
1251 fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile);
3b7344d5 1252 if (fn_sym.minsym == NULL)
b18be20d
DJ
1253 return 0;
1254
77e371c0 1255 method_stop_pc = BMSYMBOL_VALUE_ADDRESS (fn_sym);
a513d1e8
LM
1256
1257 /* Some targets have minimal symbols pointing to function descriptors
1258 (powerpc 64 for example). Make sure to retrieve the address
1259 of the real function from the function descriptor before passing on
1260 the address to other layers of GDB. */
1261 func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, method_stop_pc,
1262 &current_target);
1263 if (func_addr != 0)
1264 method_stop_pc = func_addr;
1265
e76f05fa 1266 real_stop_pc = gdbarch_skip_trampoline_code
9970f04b 1267 (gdbarch, frame, method_stop_pc);
b18be20d
DJ
1268 if (real_stop_pc == 0)
1269 real_stop_pc = method_stop_pc;
1270
1271 return real_stop_pc;
1272}
1273
41f1b697
DJ
1274/* Return nonzero if a type should be passed by reference.
1275
1276 The rule in the v3 ABI document comes from section 3.1.1. If the
1277 type has a non-trivial copy constructor or destructor, then the
1278 caller must make a copy (by calling the copy constructor if there
1279 is one or perform the copy itself otherwise), pass the address of
1280 the copy, and then destroy the temporary (if necessary).
1281
1282 For return values with non-trivial copy constructors or
1283 destructors, space will be allocated in the caller, and a pointer
1284 will be passed as the first argument (preceding "this").
1285
1286 We don't have a bulletproof mechanism for determining whether a
1287 constructor or destructor is trivial. For GCC and DWARF2 debug
1288 information, we can check the artificial flag.
1289
1290 We don't do anything with the constructors or destructors,
1291 but we have to get the argument passing right anyway. */
1292static int
1293gnuv3_pass_by_reference (struct type *type)
1294{
1295 int fieldnum, fieldelem;
1296
f168693b 1297 type = check_typedef (type);
41f1b697
DJ
1298
1299 /* We're only interested in things that can have methods. */
1300 if (TYPE_CODE (type) != TYPE_CODE_STRUCT
41f1b697
DJ
1301 && TYPE_CODE (type) != TYPE_CODE_UNION)
1302 return 0;
1303
ebb8ece2
SC
1304 /* A dynamic class has a non-trivial copy constructor.
1305 See c++98 section 12.8 Copying class objects [class.copy]. */
1306 if (gnuv3_dynamic_class (type))
1307 return 1;
1308
41f1b697
DJ
1309 for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
1310 for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
1311 fieldelem++)
1312 {
1313 struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum);
0d5cff50 1314 const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum);
41f1b697
DJ
1315 struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem);
1316
1317 /* If this function is marked as artificial, it is compiler-generated,
1318 and we assume it is trivial. */
1319 if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem))
1320 continue;
1321
1322 /* If we've found a destructor, we must pass this by reference. */
1323 if (name[0] == '~')
1324 return 1;
1325
1326 /* If the mangled name of this method doesn't indicate that it
1327 is a constructor, we're not interested.
1328
1329 FIXME drow/2007-09-23: We could do this using the name of
1330 the method and the name of the class instead of dealing
1331 with the mangled name. We don't have a convenient function
1332 to strip off both leading scope qualifiers and trailing
1333 template arguments yet. */
7d27a96d
TT
1334 if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem))
1335 && !TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem))
41f1b697
DJ
1336 continue;
1337
1338 /* If this method takes two arguments, and the second argument is
1339 a reference to this class, then it is a copy constructor. */
82c48ac7
SC
1340 if (TYPE_NFIELDS (fieldtype) == 2)
1341 {
1342 struct type *arg_type = TYPE_FIELD_TYPE (fieldtype, 1);
82c48ac7 1343
3433cfa5
SC
1344 if (TYPE_CODE (arg_type) == TYPE_CODE_REF)
1345 {
1346 struct type *arg_target_type;
82c48ac7 1347
3433cfa5
SC
1348 arg_target_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
1349 if (class_types_same_p (arg_target_type, type))
1350 return 1;
1351 }
82c48ac7 1352 }
41f1b697
DJ
1353 }
1354
1355 /* Even if all the constructors and destructors were artificial, one
1356 of them may have invoked a non-artificial constructor or
1357 destructor in a base class. If any base class needs to be passed
1358 by reference, so does this class. Similarly for members, which
1359 are constructed whenever this class is. We do not need to worry
1360 about recursive loops here, since we are only looking at members
bceffbf3 1361 of complete class type. Also ignore any static members. */
41f1b697 1362 for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++)
bceffbf3
JK
1363 if (! field_is_static (&TYPE_FIELD (type, fieldnum))
1364 && gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum)))
41f1b697
DJ
1365 return 1;
1366
1367 return 0;
1368}
1369
7ed49443
JB
1370static void
1371init_gnuv3_ops (void)
1372{
0963b4bd
MS
1373 vtable_type_gdbarch_data
1374 = gdbarch_data_register_post_init (build_gdb_vtable_type);
6e72ca20
TT
1375 std_type_info_gdbarch_data
1376 = gdbarch_data_register_post_init (build_std_type_info_type);
7ed49443
JB
1377
1378 gnu_v3_abi_ops.shortname = "gnu-v3";
1379 gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI";
1380 gnu_v3_abi_ops.doc = "G++ Version 3 ABI";
358777b0
EZ
1381 gnu_v3_abi_ops.is_destructor_name =
1382 (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor;
1383 gnu_v3_abi_ops.is_constructor_name =
1384 (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor;
7ed49443
JB
1385 gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name;
1386 gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name;
1387 gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type;
1388 gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field;
1514d34e 1389 gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset;
0d5de010
DJ
1390 gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr;
1391 gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size;
1392 gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr;
1393 gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value;
c4aeac85 1394 gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable;
6e72ca20
TT
1395 gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid;
1396 gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type;
72f1fe8a 1397 gnu_v3_abi_ops.get_type_from_type_info = gnuv3_get_type_from_type_info;
cc16e6c9
TT
1398 gnu_v3_abi_ops.get_typename_from_type_info
1399 = gnuv3_get_typename_from_type_info;
b18be20d 1400 gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline;
41f1b697 1401 gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
7ed49443
JB
1402}
1403
b9362cc7 1404extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */
7ed49443
JB
1405
1406void
1407_initialize_gnu_v3_abi (void)
1408{
1409 init_gnuv3_ops ();
1410
fe1f4a5e 1411 register_cp_abi (&gnu_v3_abi_ops);
1605ef26 1412 set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname);
7ed49443 1413}