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