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1 /* Abstraction of GNU v3 abi.
2 Contributed by Jim Blandy <jimb@redhat.com>
3
4 Copyright (C) 2001-2015 Free Software Foundation, Inc.
5
6 This file is part of GDB.
7
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.
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
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20
21 #include "defs.h"
22 #include "value.h"
23 #include "cp-abi.h"
24 #include "cp-support.h"
25 #include "demangle.h"
26 #include "objfiles.h"
27 #include "valprint.h"
28 #include "c-lang.h"
29 #include "typeprint.h"
30
31 static struct cp_abi_ops gnu_v3_abi_ops;
32
33 /* A gdbarch key for std::type_info, in the event that it can't be
34 found in the debug info. */
35
36 static struct gdbarch_data *std_type_info_gdbarch_data;
37
38
39 static int
40 gnuv3_is_vtable_name (const char *name)
41 {
42 return startswith (name, "_ZTV");
43 }
44
45 static int
46 gnuv3_is_operator_name (const char *name)
47 {
48 return startswith (name, "operator");
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. */
89 static struct gdbarch_data *vtable_type_gdbarch_data;
90
91
92 /* Human-readable names for the numbers of the fields above. */
93 enum {
94 vtable_field_vcall_and_vbase_offsets,
95 vtable_field_offset_to_top,
96 vtable_field_type_info,
97 vtable_field_virtual_functions
98 };
99
100
101 /* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable',
102 described above, laid out appropriately for ARCH.
103
104 We use this function as the gdbarch per-architecture data
105 initialization function. */
106 static void *
107 build_gdb_vtable_type (struct gdbarch *arch)
108 {
109 struct type *t;
110 struct field *field_list, *field;
111 int offset;
112
113 struct type *void_ptr_type
114 = builtin_type (arch)->builtin_data_ptr;
115 struct type *ptr_to_void_fn_type
116 = builtin_type (arch)->builtin_func_ptr;
117
118 /* ARCH can't give us the true ptrdiff_t type, so we guess. */
119 struct type *ptrdiff_type
120 = arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t");
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";
135 FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1);
136 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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;
143 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
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;
150 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
151 offset += TYPE_LENGTH (FIELD_TYPE (*field));
152 field++;
153
154 /* void (*virtual_functions[0]) (); */
155 FIELD_NAME (*field) = "virtual_functions";
156 FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1);
157 SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
158 offset += TYPE_LENGTH (FIELD_TYPE (*field));
159 field++;
160
161 /* We assumed in the allocation above that there were four fields. */
162 gdb_assert (field == (field_list + 4));
163
164 t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
165 TYPE_NFIELDS (t) = field - field_list;
166 TYPE_FIELDS (t) = field_list;
167 TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable";
168 INIT_CPLUS_SPECIFIC (t);
169
170 return make_type_with_address_space (t, TYPE_INSTANCE_FLAG_CODE_SPACE);
171 }
172
173
174 /* Return the ptrdiff_t type used in the vtable type. */
175 static struct type *
176 vtable_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
184 /* Return the offset from the start of the imaginary `struct
185 gdb_gnu_v3_abi_vtable' object to the vtable's "address point"
186 (i.e., where objects' virtual table pointers point). */
187 static int
188 vtable_address_point_offset (struct gdbarch *gdbarch)
189 {
190 struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
191
192 return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions)
193 / TARGET_CHAR_BIT);
194 }
195
196
197 /* Determine whether structure TYPE is a dynamic class. Cache the
198 result. */
199
200 static int
201 gnuv3_dynamic_class (struct type *type)
202 {
203 int fieldnum, fieldelem;
204
205 CHECK_TYPEDEF (type);
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
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
246 static struct value *
247 gnuv3_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
256 CHECK_TYPEDEF (container_type);
257 gdb_assert (TYPE_CODE (container_type) == TYPE_CODE_STRUCT);
258
259 /* If this type does not have a virtual table, don't read the first
260 field. */
261 if (!gnuv3_dynamic_class (container_type))
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,
281 vtable_address
282 - vtable_address_point_offset (gdbarch));
283 }
284
285
286 static struct type *
287 gnuv3_rtti_type (struct value *value,
288 int *full_p, int *top_p, int *using_enc_p)
289 {
290 struct gdbarch *gdbarch;
291 struct type *values_type = check_typedef (value_type (value));
292 struct value *vtable;
293 struct minimal_symbol *vtable_symbol;
294 const char *vtable_symbol_name;
295 const char *class_name;
296 struct type *run_time_type;
297 LONGEST offset_to_top;
298 char *atsign;
299
300 /* We only have RTTI for class objects. */
301 if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
302 return NULL;
303
304 /* Java doesn't have RTTI following the C++ ABI. */
305 if (TYPE_CPLUS_REALLY_JAVA (values_type))
306 return NULL;
307
308 /* Determine architecture. */
309 gdbarch = get_type_arch (values_type);
310
311 if (using_enc_p)
312 *using_enc_p = 0;
313
314 vtable = gnuv3_get_vtable (gdbarch, values_type,
315 value_as_address (value_addr (value)));
316 if (vtable == NULL)
317 return NULL;
318
319 /* Find the linker symbol for this vtable. */
320 vtable_symbol
321 = lookup_minimal_symbol_by_pc (value_address (vtable)
322 + value_embedded_offset (vtable)).minsym;
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. */
331 vtable_symbol_name = MSYMBOL_DEMANGLED_NAME (vtable_symbol);
332 if (vtable_symbol_name == NULL
333 || !startswith (vtable_symbol_name, "vtable for "))
334 {
335 warning (_("can't find linker symbol for virtual table for `%s' value"),
336 TYPE_SAFE_NAME (values_type));
337 if (vtable_symbol_name)
338 warning (_(" found `%s' instead"), vtable_symbol_name);
339 return NULL;
340 }
341 class_name = vtable_symbol_name + 11;
342
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
355 /* Try to look up the class name as a type name. */
356 /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
357 run_time_type = cp_lookup_rtti_type (class_name, NULL);
358 if (run_time_type == NULL)
359 return NULL;
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)
367 *full_p = (- offset_to_top == value_embedded_offset (value)
368 && (TYPE_LENGTH (value_enclosing_type (value))
369 >= TYPE_LENGTH (run_time_type)));
370 if (top_p)
371 *top_p = - offset_to_top;
372 return run_time_type;
373 }
374
375 /* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
376 function, of type FNTYPE. */
377
378 static struct value *
379 gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container,
380 struct type *fntype, int vtable_index)
381 {
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);
388
389 /* Fetch the appropriate function pointer from the vtable. */
390 vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions),
391 vtable_index);
392
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. */
398 if (gdbarch_vtable_function_descriptors (gdbarch))
399 vfn = value_addr (vfn);
400
401 /* Cast the function pointer to the appropriate type. */
402 vfn = value_cast (lookup_pointer_type (fntype), vfn);
403
404 return vfn;
405 }
406
407 /* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h
408 for a description of the arguments. */
409
410 static struct value *
411 gnuv3_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));
416 struct gdbarch *gdbarch;
417
418 /* Some simple sanity checks. */
419 if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
420 error (_("Only classes can have virtual functions."));
421
422 /* Determine architecture. */
423 gdbarch = get_type_arch (values_type);
424
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
431 return gnuv3_get_virtual_fn (gdbarch, *value_p, TYPE_FN_FIELD_TYPE (f, j),
432 TYPE_FN_FIELD_VOFFSET (f, j));
433 }
434
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
441 -1 is returned on error. */
442
443 static int
444 gnuv3_baseclass_offset (struct type *type, int index,
445 const bfd_byte *valaddr, int embedded_offset,
446 CORE_ADDR address, const struct value *val)
447 {
448 struct gdbarch *gdbarch;
449 struct type *ptr_type;
450 struct value *vtable;
451 struct value *vbase_array;
452 long int cur_base_offset, base_offset;
453
454 /* Determine architecture. */
455 gdbarch = get_type_arch (type);
456 ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
457
458 /* If it isn't a virtual base, this is easy. The offset is in the
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))
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;
470 if (cur_base_offset >= - vtable_address_point_offset (gdbarch))
471 error (_("Expected a negative vbase offset (old compiler?)"));
472
473 cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch);
474 if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0)
475 error (_("Misaligned vbase offset."));
476 cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type));
477
478 vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset);
479 gdb_assert (vtable != NULL);
480 vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets);
481 base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset));
482 return base_offset;
483 }
484
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
489 static const char *
490 gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset,
491 LONGEST adjustment)
492 {
493 int i;
494
495 /* Search this class first. */
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
537 /* Decode GNU v3 method pointer. */
538
539 static int
540 gnuv3_decode_method_ptr (struct gdbarch *gdbarch,
541 const gdb_byte *contents,
542 CORE_ADDR *value_p,
543 LONGEST *adjustment_p)
544 {
545 struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr;
546 struct type *offset_type = vtable_ptrdiff_type (gdbarch);
547 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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);
559 voffset = extract_signed_integer (contents,
560 TYPE_LENGTH (funcptr_type), byte_order);
561 contents += TYPE_LENGTH (funcptr_type);
562 adjustment = extract_signed_integer (contents,
563 TYPE_LENGTH (offset_type), byte_order);
564
565 if (!gdbarch_vbit_in_delta (gdbarch))
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
581 /* GNU v3 implementation of cplus_print_method_ptr. */
582
583 static void
584 gnuv3_print_method_ptr (const gdb_byte *contents,
585 struct type *type,
586 struct ui_file *stream)
587 {
588 struct type *self_type = TYPE_SELF_TYPE (type);
589 struct gdbarch *gdbarch = get_type_arch (self_type);
590 CORE_ADDR ptr_value;
591 LONGEST adjustment;
592 int vbit;
593
594 /* Extract the pointer to member. */
595 vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
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. */
613 voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
614
615 physname = gnuv3_find_method_in (self_type, voffset, adjustment);
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 {
621 char *demangled_name = gdb_demangle (physname,
622 DMGL_ANSI | DMGL_PARAMS);
623
624 fprintf_filtered (stream, "&virtual ");
625 if (demangled_name == NULL)
626 fputs_filtered (physname, stream);
627 else
628 {
629 fputs_filtered (demangled_name, stream);
630 xfree (demangled_name);
631 }
632 return;
633 }
634 }
635 else if (ptr_value != 0)
636 {
637 /* Found a non-virtual function: print out the type. */
638 fputs_filtered ("(", stream);
639 c_print_type (type, "", stream, -1, 0, &type_print_raw_options);
640 fputs_filtered (") ", stream);
641 }
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
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 }
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
666 static int
667 gnuv3_method_ptr_size (struct type *type)
668 {
669 struct gdbarch *gdbarch = get_type_arch (type);
670
671 return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
672 }
673
674 /* GNU v3 implementation of cplus_make_method_ptr. */
675
676 static void
677 gnuv3_make_method_ptr (struct type *type, gdb_byte *contents,
678 CORE_ADDR value, int is_virtual)
679 {
680 struct gdbarch *gdbarch = get_type_arch (type);
681 int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
682 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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
693 if (!gdbarch_vbit_in_delta (gdbarch))
694 {
695 store_unsigned_integer (contents, size, byte_order, value | is_virtual);
696 store_unsigned_integer (contents + size, size, byte_order, 0);
697 }
698 else
699 {
700 store_unsigned_integer (contents, size, byte_order, value);
701 store_unsigned_integer (contents + size, size, byte_order, is_virtual);
702 }
703 }
704
705 /* GNU v3 implementation of cplus_method_ptr_to_value. */
706
707 static struct value *
708 gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
709 {
710 struct gdbarch *gdbarch;
711 const gdb_byte *contents = value_contents (method_ptr);
712 CORE_ADDR ptr_value;
713 struct type *self_type, *final_type, *method_type;
714 LONGEST adjustment;
715 int vbit;
716
717 self_type = TYPE_SELF_TYPE (check_typedef (value_type (method_ptr)));
718 final_type = lookup_pointer_type (self_type);
719
720 method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
721
722 /* Extract the pointer to member. */
723 gdbarch = get_type_arch (self_type);
724 vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
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. */
745 *this_p = value_cast (builtin_type (gdbarch)->builtin_data_ptr, *this_p);
746 *this_p = value_ptradd (*this_p, adjustment);
747 *this_p = value_cast (final_type, *this_p);
748
749 if (vbit)
750 {
751 LONGEST voffset;
752
753 voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
754 return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p),
755 method_type, voffset);
756 }
757 else
758 return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
759 }
760
761 /* Objects of this type are stored in a hash table and a vector when
762 printing the vtables for a class. */
763
764 struct 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
774 typedef struct value_and_voffset *value_and_voffset_p;
775 DEF_VEC_P (value_and_voffset_p);
776
777 /* Hash function for value_and_voffset. */
778
779 static hashval_t
780 hash_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
789 static int
790 eq_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
801 static int
802 compare_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
824 static void
825 compute_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;
833
834 gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT);
835
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
881 static void
882 print_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 {
905 /* Initialize it just to avoid a GCC false warning. */
906 CORE_ADDR addr = 0;
907 int got_error = 0;
908 struct value *vfn;
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
919 TRY
920 {
921 addr = value_as_address (vfn);
922 }
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)
931 print_function_pointer_address (opts, gdbarch, addr, gdb_stdout);
932 printf_filtered ("\n");
933 }
934 }
935
936 /* Implementation of the print_vtable method. */
937
938 static void
939 gnuv3_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;
947 VEC (value_and_voffset_p) *result_vec = NULL;
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);
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)));
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
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
1015 static void *
1016 build_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
1060 static struct type *
1061 gnuv3_get_typeid_type (struct gdbarch *gdbarch)
1062 {
1063 struct symbol *typeinfo;
1064 struct type *typeinfo_type;
1065
1066 typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN, NULL);
1067 if (typeinfo == NULL)
1068 typeinfo_type = gdbarch_data (gdbarch, std_type_info_gdbarch_data);
1069 else
1070 typeinfo_type = SYMBOL_TYPE (typeinfo);
1071
1072 return typeinfo_type;
1073 }
1074
1075 /* Implement the 'get_typeid' method. */
1076
1077 static struct value *
1078 gnuv3_get_typeid (struct value *value)
1079 {
1080 struct type *typeinfo_type;
1081 struct type *type;
1082 struct gdbarch *gdbarch;
1083 struct cleanup *cleanup;
1084 struct value *result;
1085 char *type_name, *canonical;
1086
1087 /* We have to handle values a bit trickily here, to allow this code
1088 to work properly with non_lvalue values that are really just
1089 disguised types. */
1090 if (value_lval_const (value) == lval_memory)
1091 value = coerce_ref (value);
1092
1093 type = check_typedef (value_type (value));
1094
1095 /* In the non_lvalue case, a reference might have slipped through
1096 here. */
1097 if (TYPE_CODE (type) == TYPE_CODE_REF)
1098 type = check_typedef (TYPE_TARGET_TYPE (type));
1099
1100 /* Ignore top-level cv-qualifiers. */
1101 type = make_cv_type (0, 0, type, NULL);
1102 gdbarch = get_type_arch (type);
1103
1104 type_name = type_to_string (type);
1105 if (type_name == NULL)
1106 error (_("cannot find typeinfo for unnamed type"));
1107 cleanup = make_cleanup (xfree, type_name);
1108
1109 /* We need to canonicalize the type name here, because we do lookups
1110 using the demangled name, and so we must match the format it
1111 uses. E.g., GDB tends to use "const char *" as a type name, but
1112 the demangler uses "char const *". */
1113 canonical = cp_canonicalize_string (type_name);
1114 if (canonical != NULL)
1115 {
1116 make_cleanup (xfree, canonical);
1117 type_name = canonical;
1118 }
1119
1120 typeinfo_type = gnuv3_get_typeid_type (gdbarch);
1121
1122 /* We check for lval_memory because in the "typeid (type-id)" case,
1123 the type is passed via a not_lval value object. */
1124 if (TYPE_CODE (type) == TYPE_CODE_STRUCT
1125 && value_lval_const (value) == lval_memory
1126 && gnuv3_dynamic_class (type))
1127 {
1128 struct value *vtable, *typeinfo_value;
1129 CORE_ADDR address = value_address (value) + value_embedded_offset (value);
1130
1131 vtable = gnuv3_get_vtable (gdbarch, type, address);
1132 if (vtable == NULL)
1133 error (_("cannot find typeinfo for object of type '%s'"), type_name);
1134 typeinfo_value = value_field (vtable, vtable_field_type_info);
1135 result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL),
1136 typeinfo_value));
1137 }
1138 else
1139 {
1140 char *sym_name;
1141 struct bound_minimal_symbol minsym;
1142
1143 sym_name = concat ("typeinfo for ", type_name, (char *) NULL);
1144 make_cleanup (xfree, sym_name);
1145 minsym = lookup_minimal_symbol (sym_name, NULL, NULL);
1146
1147 if (minsym.minsym == NULL)
1148 error (_("could not find typeinfo symbol for '%s'"), type_name);
1149
1150 result = value_at_lazy (typeinfo_type, BMSYMBOL_VALUE_ADDRESS (minsym));
1151 }
1152
1153 do_cleanups (cleanup);
1154 return result;
1155 }
1156
1157 /* Implement the 'get_typename_from_type_info' method. */
1158
1159 static char *
1160 gnuv3_get_typename_from_type_info (struct value *type_info_ptr)
1161 {
1162 struct gdbarch *gdbarch = get_type_arch (value_type (type_info_ptr));
1163 struct bound_minimal_symbol typeinfo_sym;
1164 CORE_ADDR addr;
1165 const char *symname;
1166 const char *class_name;
1167 const char *atsign;
1168
1169 addr = value_as_address (type_info_ptr);
1170 typeinfo_sym = lookup_minimal_symbol_by_pc (addr);
1171 if (typeinfo_sym.minsym == NULL)
1172 error (_("could not find minimal symbol for typeinfo address %s"),
1173 paddress (gdbarch, addr));
1174
1175 #define TYPEINFO_PREFIX "typeinfo for "
1176 #define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1)
1177 symname = MSYMBOL_DEMANGLED_NAME (typeinfo_sym.minsym);
1178 if (symname == NULL || strncmp (symname, TYPEINFO_PREFIX,
1179 TYPEINFO_PREFIX_LEN))
1180 error (_("typeinfo symbol '%s' has unexpected name"),
1181 MSYMBOL_LINKAGE_NAME (typeinfo_sym.minsym));
1182 class_name = symname + TYPEINFO_PREFIX_LEN;
1183
1184 /* Strip off @plt and version suffixes. */
1185 atsign = strchr (class_name, '@');
1186 if (atsign != NULL)
1187 return savestring (class_name, atsign - class_name);
1188 return xstrdup (class_name);
1189 }
1190
1191 /* Implement the 'get_type_from_type_info' method. */
1192
1193 static struct type *
1194 gnuv3_get_type_from_type_info (struct value *type_info_ptr)
1195 {
1196 char *type_name;
1197 struct cleanup *cleanup;
1198 struct value *type_val;
1199 struct expression *expr;
1200 struct type *result;
1201
1202 type_name = gnuv3_get_typename_from_type_info (type_info_ptr);
1203 cleanup = make_cleanup (xfree, type_name);
1204
1205 /* We have to parse the type name, since in general there is not a
1206 symbol for a type. This is somewhat bogus since there may be a
1207 mis-parse. Another approach might be to re-use the demangler's
1208 internal form to reconstruct the type somehow. */
1209
1210 expr = parse_expression (type_name);
1211 make_cleanup (xfree, expr);
1212
1213 type_val = evaluate_type (expr);
1214 result = value_type (type_val);
1215
1216 do_cleanups (cleanup);
1217 return result;
1218 }
1219
1220 /* Determine if we are currently in a C++ thunk. If so, get the address
1221 of the routine we are thunking to and continue to there instead. */
1222
1223 static CORE_ADDR
1224 gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc)
1225 {
1226 CORE_ADDR real_stop_pc, method_stop_pc, func_addr;
1227 struct gdbarch *gdbarch = get_frame_arch (frame);
1228 struct bound_minimal_symbol thunk_sym, fn_sym;
1229 struct obj_section *section;
1230 const char *thunk_name, *fn_name;
1231
1232 real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
1233 if (real_stop_pc == 0)
1234 real_stop_pc = stop_pc;
1235
1236 /* Find the linker symbol for this potential thunk. */
1237 thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc);
1238 section = find_pc_section (real_stop_pc);
1239 if (thunk_sym.minsym == NULL || section == NULL)
1240 return 0;
1241
1242 /* The symbol's demangled name should be something like "virtual
1243 thunk to FUNCTION", where FUNCTION is the name of the function
1244 being thunked to. */
1245 thunk_name = MSYMBOL_DEMANGLED_NAME (thunk_sym.minsym);
1246 if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL)
1247 return 0;
1248
1249 fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to ");
1250 fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile);
1251 if (fn_sym.minsym == NULL)
1252 return 0;
1253
1254 method_stop_pc = BMSYMBOL_VALUE_ADDRESS (fn_sym);
1255
1256 /* Some targets have minimal symbols pointing to function descriptors
1257 (powerpc 64 for example). Make sure to retrieve the address
1258 of the real function from the function descriptor before passing on
1259 the address to other layers of GDB. */
1260 func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, method_stop_pc,
1261 &current_target);
1262 if (func_addr != 0)
1263 method_stop_pc = func_addr;
1264
1265 real_stop_pc = gdbarch_skip_trampoline_code
1266 (gdbarch, frame, method_stop_pc);
1267 if (real_stop_pc == 0)
1268 real_stop_pc = method_stop_pc;
1269
1270 return real_stop_pc;
1271 }
1272
1273 /* Return nonzero if a type should be passed by reference.
1274
1275 The rule in the v3 ABI document comes from section 3.1.1. If the
1276 type has a non-trivial copy constructor or destructor, then the
1277 caller must make a copy (by calling the copy constructor if there
1278 is one or perform the copy itself otherwise), pass the address of
1279 the copy, and then destroy the temporary (if necessary).
1280
1281 For return values with non-trivial copy constructors or
1282 destructors, space will be allocated in the caller, and a pointer
1283 will be passed as the first argument (preceding "this").
1284
1285 We don't have a bulletproof mechanism for determining whether a
1286 constructor or destructor is trivial. For GCC and DWARF2 debug
1287 information, we can check the artificial flag.
1288
1289 We don't do anything with the constructors or destructors,
1290 but we have to get the argument passing right anyway. */
1291 static int
1292 gnuv3_pass_by_reference (struct type *type)
1293 {
1294 int fieldnum, fieldelem;
1295
1296 CHECK_TYPEDEF (type);
1297
1298 /* We're only interested in things that can have methods. */
1299 if (TYPE_CODE (type) != TYPE_CODE_STRUCT
1300 && TYPE_CODE (type) != TYPE_CODE_UNION)
1301 return 0;
1302
1303 /* A dynamic class has a non-trivial copy constructor.
1304 See c++98 section 12.8 Copying class objects [class.copy]. */
1305 if (gnuv3_dynamic_class (type))
1306 return 1;
1307
1308 for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
1309 for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
1310 fieldelem++)
1311 {
1312 struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum);
1313 const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum);
1314 struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem);
1315
1316 /* If this function is marked as artificial, it is compiler-generated,
1317 and we assume it is trivial. */
1318 if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem))
1319 continue;
1320
1321 /* If we've found a destructor, we must pass this by reference. */
1322 if (name[0] == '~')
1323 return 1;
1324
1325 /* If the mangled name of this method doesn't indicate that it
1326 is a constructor, we're not interested.
1327
1328 FIXME drow/2007-09-23: We could do this using the name of
1329 the method and the name of the class instead of dealing
1330 with the mangled name. We don't have a convenient function
1331 to strip off both leading scope qualifiers and trailing
1332 template arguments yet. */
1333 if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem))
1334 && !TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem))
1335 continue;
1336
1337 /* If this method takes two arguments, and the second argument is
1338 a reference to this class, then it is a copy constructor. */
1339 if (TYPE_NFIELDS (fieldtype) == 2)
1340 {
1341 struct type *arg_type = TYPE_FIELD_TYPE (fieldtype, 1);
1342
1343 if (TYPE_CODE (arg_type) == TYPE_CODE_REF)
1344 {
1345 struct type *arg_target_type;
1346
1347 arg_target_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
1348 if (class_types_same_p (arg_target_type, type))
1349 return 1;
1350 }
1351 }
1352 }
1353
1354 /* Even if all the constructors and destructors were artificial, one
1355 of them may have invoked a non-artificial constructor or
1356 destructor in a base class. If any base class needs to be passed
1357 by reference, so does this class. Similarly for members, which
1358 are constructed whenever this class is. We do not need to worry
1359 about recursive loops here, since we are only looking at members
1360 of complete class type. Also ignore any static members. */
1361 for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++)
1362 if (! field_is_static (&TYPE_FIELD (type, fieldnum))
1363 && gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum)))
1364 return 1;
1365
1366 return 0;
1367 }
1368
1369 static void
1370 init_gnuv3_ops (void)
1371 {
1372 vtable_type_gdbarch_data
1373 = gdbarch_data_register_post_init (build_gdb_vtable_type);
1374 std_type_info_gdbarch_data
1375 = gdbarch_data_register_post_init (build_std_type_info_type);
1376
1377 gnu_v3_abi_ops.shortname = "gnu-v3";
1378 gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI";
1379 gnu_v3_abi_ops.doc = "G++ Version 3 ABI";
1380 gnu_v3_abi_ops.is_destructor_name =
1381 (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor;
1382 gnu_v3_abi_ops.is_constructor_name =
1383 (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor;
1384 gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name;
1385 gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name;
1386 gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type;
1387 gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field;
1388 gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset;
1389 gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr;
1390 gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size;
1391 gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr;
1392 gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value;
1393 gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable;
1394 gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid;
1395 gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type;
1396 gnu_v3_abi_ops.get_type_from_type_info = gnuv3_get_type_from_type_info;
1397 gnu_v3_abi_ops.get_typename_from_type_info
1398 = gnuv3_get_typename_from_type_info;
1399 gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline;
1400 gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
1401 }
1402
1403 extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */
1404
1405 void
1406 _initialize_gnu_v3_abi (void)
1407 {
1408 init_gnuv3_ops ();
1409
1410 register_cp_abi (&gnu_v3_abi_ops);
1411 set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname);
1412 }