1 /* Abstraction of GNU v3 abi.
2 Contributed by Jim Blandy <jimb@redhat.com>
4 Copyright (C) 2001-2023 Free Software Foundation, Inc.
6 This file is part of GDB.
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.
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.
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/>. */
25 #include "cp-support.h"
31 #include "typeprint.h"
33 #include "cli/cli-style.h"
34 #include "dwarf2/loc.h"
37 static struct cp_abi_ops gnu_v3_abi_ops
;
39 /* A gdbarch key for std::type_info, in the event that it can't be
40 found in the debug info. */
42 static const registry
<gdbarch
>::key
<struct type
> std_type_info_gdbarch_data
;
46 gnuv3_is_vtable_name (const char *name
)
48 return startswith (name
, "_ZTV");
52 gnuv3_is_operator_name (const char *name
)
54 return startswith (name
, CP_OPERATOR_STR
);
58 /* To help us find the components of a vtable, we build ourselves a
59 GDB type object representing the vtable structure. Following the
60 V3 ABI, it goes something like this:
62 struct gdb_gnu_v3_abi_vtable {
64 / * An array of virtual call and virtual base offsets. The real
65 length of this array depends on the class hierarchy; we use
66 negative subscripts to access the elements. Yucky, but
67 better than the alternatives. * /
68 ptrdiff_t vcall_and_vbase_offsets[0];
70 / * The offset from a virtual pointer referring to this table
71 to the top of the complete object. * /
72 ptrdiff_t offset_to_top;
74 / * The type_info pointer for this class. This is really a
75 std::type_info *, but GDB doesn't really look at the
76 type_info object itself, so we don't bother to get the type
80 / * Virtual table pointers in objects point here. * /
82 / * Virtual function pointers. Like the vcall/vbase array, the
83 real length of this table depends on the class hierarchy. * /
84 void (*virtual_functions[0]) ();
88 The catch, of course, is that the exact layout of this table
89 depends on the ABI --- word size, endianness, alignment, etc. So
90 the GDB type object is actually a per-architecture kind of thing.
92 vtable_type_gdbarch_data is a gdbarch per-architecture data pointer
93 which refers to the struct type * for this structure, laid out
94 appropriately for the architecture. */
95 static const registry
<gdbarch
>::key
<struct type
> vtable_type_gdbarch_data
;
98 /* Human-readable names for the numbers of the fields above. */
100 vtable_field_vcall_and_vbase_offsets
,
101 vtable_field_offset_to_top
,
102 vtable_field_type_info
,
103 vtable_field_virtual_functions
107 /* Return a GDB type representing `struct gdb_gnu_v3_abi_vtable',
108 described above, laid out appropriately for ARCH.
110 We use this function as the gdbarch per-architecture data
111 initialization function. */
113 get_gdb_vtable_type (struct gdbarch
*arch
)
118 struct type
*result
= vtable_type_gdbarch_data
.get (arch
);
119 if (result
!= nullptr)
122 struct type
*void_ptr_type
123 = builtin_type (arch
)->builtin_data_ptr
;
124 struct type
*ptr_to_void_fn_type
125 = builtin_type (arch
)->builtin_func_ptr
;
127 type_allocator
alloc (arch
);
129 /* ARCH can't give us the true ptrdiff_t type, so we guess. */
130 struct type
*ptrdiff_type
131 = init_integer_type (alloc
, gdbarch_ptr_bit (arch
), 0, "ptrdiff_t");
133 t
= alloc
.new_type (TYPE_CODE_STRUCT
, 0, nullptr);
135 /* We assume no padding is necessary, since GDB doesn't know
136 anything about alignment at the moment. If this assumption bites
137 us, we should add a gdbarch method which, given a type, returns
138 the alignment that type requires, and then use that here. */
140 /* Build the field list. */
145 /* ptrdiff_t vcall_and_vbase_offsets[0]; */
147 struct field
&field0
= t
->field (0);
148 field0
.set_name ("vcall_and_vbase_offsets");
149 field0
.set_type (lookup_array_range_type (ptrdiff_type
, 0, -1));
150 field0
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
151 offset
+= field0
.type ()->length ();
154 /* ptrdiff_t offset_to_top; */
156 struct field
&field1
= t
->field (1);
157 field1
.set_name ("offset_to_top");
158 field1
.set_type (ptrdiff_type
);
159 field1
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
160 offset
+= field1
.type ()->length ();
163 /* void *type_info; */
165 struct field
&field2
= t
->field (2);
166 field2
.set_name ("type_info");
167 field2
.set_type (void_ptr_type
);
168 field2
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
169 offset
+= field2
.type ()->length ();
172 /* void (*virtual_functions[0]) (); */
174 struct field
&field3
= t
->field (3);
175 field3
.set_name ("virtual_functions");
176 field3
.set_type (lookup_array_range_type (ptr_to_void_fn_type
, 0, -1));
177 field3
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
178 offset
+= field3
.type ()->length ();
181 t
->set_length (offset
);
183 t
->set_name ("gdb_gnu_v3_abi_vtable");
184 INIT_CPLUS_SPECIFIC (t
);
186 result
= make_type_with_address_space (t
, TYPE_INSTANCE_FLAG_CODE_SPACE
);
187 vtable_type_gdbarch_data
.set (arch
, result
);
192 /* Return the ptrdiff_t type used in the vtable type. */
194 vtable_ptrdiff_type (struct gdbarch
*gdbarch
)
196 struct type
*vtable_type
= get_gdb_vtable_type (gdbarch
);
198 /* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */
199 return vtable_type
->field (vtable_field_offset_to_top
).type ();
202 /* Return the offset from the start of the imaginary `struct
203 gdb_gnu_v3_abi_vtable' object to the vtable's "address point"
204 (i.e., where objects' virtual table pointers point). */
206 vtable_address_point_offset (struct gdbarch
*gdbarch
)
208 struct type
*vtable_type
= get_gdb_vtable_type (gdbarch
);
210 return (vtable_type
->field (vtable_field_virtual_functions
).loc_bitpos ()
215 /* Determine whether structure TYPE is a dynamic class. Cache the
219 gnuv3_dynamic_class (struct type
*type
)
221 int fieldnum
, fieldelem
;
223 type
= check_typedef (type
);
224 gdb_assert (type
->code () == TYPE_CODE_STRUCT
225 || type
->code () == TYPE_CODE_UNION
);
227 if (type
->code () == TYPE_CODE_UNION
)
230 if (TYPE_CPLUS_DYNAMIC (type
))
231 return TYPE_CPLUS_DYNAMIC (type
) == 1;
233 ALLOCATE_CPLUS_STRUCT_TYPE (type
);
235 for (fieldnum
= 0; fieldnum
< TYPE_N_BASECLASSES (type
); fieldnum
++)
236 if (BASETYPE_VIA_VIRTUAL (type
, fieldnum
)
237 || gnuv3_dynamic_class (type
->field (fieldnum
).type ()))
239 TYPE_CPLUS_DYNAMIC (type
) = 1;
243 for (fieldnum
= 0; fieldnum
< TYPE_NFN_FIELDS (type
); fieldnum
++)
244 for (fieldelem
= 0; fieldelem
< TYPE_FN_FIELDLIST_LENGTH (type
, fieldnum
);
247 struct fn_field
*f
= TYPE_FN_FIELDLIST1 (type
, fieldnum
);
249 if (TYPE_FN_FIELD_VIRTUAL_P (f
, fieldelem
))
251 TYPE_CPLUS_DYNAMIC (type
) = 1;
256 TYPE_CPLUS_DYNAMIC (type
) = -1;
260 /* Find the vtable for a value of CONTAINER_TYPE located at
261 CONTAINER_ADDR. Return a value of the correct vtable type for this
262 architecture, or NULL if CONTAINER does not have a vtable. */
264 static struct value
*
265 gnuv3_get_vtable (struct gdbarch
*gdbarch
,
266 struct type
*container_type
, CORE_ADDR container_addr
)
268 struct type
*vtable_type
= get_gdb_vtable_type (gdbarch
);
269 struct type
*vtable_pointer_type
;
270 struct value
*vtable_pointer
;
271 CORE_ADDR vtable_address
;
273 container_type
= check_typedef (container_type
);
274 gdb_assert (container_type
->code () == TYPE_CODE_STRUCT
);
276 /* If this type does not have a virtual table, don't read the first
278 if (!gnuv3_dynamic_class (container_type
))
281 /* We do not consult the debug information to find the virtual table.
282 The ABI specifies that it is always at offset zero in any class,
283 and debug information may not represent it.
285 We avoid using value_contents on principle, because the object might
288 /* Find the type "pointer to virtual table". */
289 vtable_pointer_type
= lookup_pointer_type (vtable_type
);
291 /* Load it from the start of the class. */
292 vtable_pointer
= value_at (vtable_pointer_type
, container_addr
);
293 vtable_address
= value_as_address (vtable_pointer
);
295 /* Correct it to point at the start of the virtual table, rather
296 than the address point. */
297 return value_at_lazy (vtable_type
,
299 - vtable_address_point_offset (gdbarch
));
304 gnuv3_rtti_type (struct value
*value
,
305 int *full_p
, LONGEST
*top_p
, int *using_enc_p
)
307 struct gdbarch
*gdbarch
;
308 struct type
*values_type
= check_typedef (value
->type ());
309 struct value
*vtable
;
310 struct minimal_symbol
*vtable_symbol
;
311 const char *vtable_symbol_name
;
312 const char *class_name
;
313 struct type
*run_time_type
;
314 LONGEST offset_to_top
;
317 /* We only have RTTI for dynamic class objects. */
318 if (values_type
->code () != TYPE_CODE_STRUCT
319 || !gnuv3_dynamic_class (values_type
))
322 /* Determine architecture. */
323 gdbarch
= values_type
->arch ();
328 vtable
= gnuv3_get_vtable (gdbarch
, values_type
,
329 value_as_address (value_addr (value
)));
333 /* Find the linker symbol for this vtable. */
335 = lookup_minimal_symbol_by_pc (vtable
->address ()
336 + vtable
->embedded_offset ()).minsym
;
340 /* The symbol's demangled name should be something like "vtable for
341 CLASS", where CLASS is the name of the run-time type of VALUE.
342 If we didn't like this approach, we could instead look in the
343 type_info object itself to get the class name. But this way
344 should work just as well, and doesn't read target memory. */
345 vtable_symbol_name
= vtable_symbol
->demangled_name ();
346 if (vtable_symbol_name
== NULL
347 || !startswith (vtable_symbol_name
, "vtable for "))
349 warning (_("can't find linker symbol for virtual table for `%s' value"),
350 TYPE_SAFE_NAME (values_type
));
351 if (vtable_symbol_name
)
352 warning (_(" found `%s' instead"), vtable_symbol_name
);
355 class_name
= vtable_symbol_name
+ 11;
357 /* Strip off @plt and version suffixes. */
358 atsign
= strchr (class_name
, '@');
363 copy
= (char *) alloca (atsign
- class_name
+ 1);
364 memcpy (copy
, class_name
, atsign
- class_name
);
365 copy
[atsign
- class_name
] = '\0';
369 /* Try to look up the class name as a type name. */
370 /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
371 run_time_type
= cp_lookup_rtti_type (class_name
, NULL
);
372 if (run_time_type
== NULL
)
375 /* Get the offset from VALUE to the top of the complete object.
376 NOTE: this is the reverse of the meaning of *TOP_P. */
378 = value_as_long (value_field (vtable
, vtable_field_offset_to_top
));
381 *full_p
= (- offset_to_top
== value
->embedded_offset ()
382 && (value
->enclosing_type ()->length ()
383 >= run_time_type
->length ()));
385 *top_p
= - offset_to_top
;
386 return run_time_type
;
389 /* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
390 function, of type FNTYPE. */
392 static struct value
*
393 gnuv3_get_virtual_fn (struct gdbarch
*gdbarch
, struct value
*container
,
394 struct type
*fntype
, int vtable_index
)
396 struct value
*vtable
, *vfn
;
398 /* Every class with virtual functions must have a vtable. */
399 vtable
= gnuv3_get_vtable (gdbarch
, container
->type (),
400 value_as_address (value_addr (container
)));
401 gdb_assert (vtable
!= NULL
);
403 /* Fetch the appropriate function pointer from the vtable. */
404 vfn
= value_subscript (value_field (vtable
, vtable_field_virtual_functions
),
407 /* If this architecture uses function descriptors directly in the vtable,
408 then the address of the vtable entry is actually a "function pointer"
409 (i.e. points to the descriptor). We don't need to scale the index
410 by the size of a function descriptor; GCC does that before outputting
411 debug information. */
412 if (gdbarch_vtable_function_descriptors (gdbarch
))
413 vfn
= value_addr (vfn
);
415 /* Cast the function pointer to the appropriate type. */
416 vfn
= value_cast (lookup_pointer_type (fntype
), vfn
);
421 /* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h
422 for a description of the arguments. */
424 static struct value
*
425 gnuv3_virtual_fn_field (struct value
**value_p
,
426 struct fn_field
*f
, int j
,
427 struct type
*vfn_base
, int offset
)
429 struct type
*values_type
= check_typedef ((*value_p
)->type ());
430 struct gdbarch
*gdbarch
;
432 /* Some simple sanity checks. */
433 if (values_type
->code () != TYPE_CODE_STRUCT
)
434 error (_("Only classes can have virtual functions."));
436 /* Determine architecture. */
437 gdbarch
= values_type
->arch ();
439 /* Cast our value to the base class which defines this virtual
440 function. This takes care of any necessary `this'
442 if (vfn_base
!= values_type
)
443 *value_p
= value_cast (vfn_base
, *value_p
);
445 return gnuv3_get_virtual_fn (gdbarch
, *value_p
, TYPE_FN_FIELD_TYPE (f
, j
),
446 TYPE_FN_FIELD_VOFFSET (f
, j
));
449 /* Compute the offset of the baseclass which is
450 the INDEXth baseclass of class TYPE,
451 for value at VALADDR (in host) at ADDRESS (in target).
452 The result is the offset of the baseclass value relative
453 to (the address of)(ARG) + OFFSET.
455 -1 is returned on error. */
458 gnuv3_baseclass_offset (struct type
*type
, int index
,
459 const bfd_byte
*valaddr
, LONGEST embedded_offset
,
460 CORE_ADDR address
, const struct value
*val
)
462 struct gdbarch
*gdbarch
;
463 struct type
*ptr_type
;
464 struct value
*vtable
;
465 struct value
*vbase_array
;
466 long int cur_base_offset
, base_offset
;
468 /* Determine architecture. */
469 gdbarch
= type
->arch ();
470 ptr_type
= builtin_type (gdbarch
)->builtin_data_ptr
;
472 /* If it isn't a virtual base, this is easy. The offset is in the
474 if (!BASETYPE_VIA_VIRTUAL (type
, index
))
475 return TYPE_BASECLASS_BITPOS (type
, index
) / 8;
477 /* If we have a DWARF expression for the offset, evaluate it. */
478 if (type
->field (index
).loc_kind () == FIELD_LOC_KIND_DWARF_BLOCK
)
480 struct dwarf2_property_baton baton
;
482 = lookup_pointer_type (type
->field (index
).type ());
483 baton
.locexpr
= *type
->field (index
).loc_dwarf_block ();
485 struct dynamic_prop prop
;
486 prop
.set_locexpr (&baton
);
488 struct property_addr_info addr_stack
;
489 addr_stack
.type
= type
;
490 /* Note that we don't set "valaddr" here. Doing so causes
491 regressions. FIXME. */
492 addr_stack
.addr
= address
+ embedded_offset
;
493 addr_stack
.next
= nullptr;
496 if (dwarf2_evaluate_property (&prop
, nullptr, &addr_stack
, &result
,
498 return (int) (result
- addr_stack
.addr
);
501 /* To access a virtual base, we need to use the vbase offset stored in
502 our vtable. Recent GCC versions provide this information. If it isn't
503 available, we could get what we needed from RTTI, or from drawing the
504 complete inheritance graph based on the debug info. Neither is
506 cur_base_offset
= TYPE_BASECLASS_BITPOS (type
, index
) / 8;
507 if (cur_base_offset
>= - vtable_address_point_offset (gdbarch
))
508 error (_("Expected a negative vbase offset (old compiler?)"));
510 cur_base_offset
= cur_base_offset
+ vtable_address_point_offset (gdbarch
);
511 if ((- cur_base_offset
) % ptr_type
->length () != 0)
512 error (_("Misaligned vbase offset."));
513 cur_base_offset
= cur_base_offset
/ ((int) ptr_type
->length ());
515 vtable
= gnuv3_get_vtable (gdbarch
, type
, address
+ embedded_offset
);
516 gdb_assert (vtable
!= NULL
);
517 vbase_array
= value_field (vtable
, vtable_field_vcall_and_vbase_offsets
);
518 base_offset
= value_as_long (value_subscript (vbase_array
, cur_base_offset
));
522 /* Locate a virtual method in DOMAIN or its non-virtual base classes
523 which has virtual table index VOFFSET. The method has an associated
524 "this" adjustment of ADJUSTMENT bytes. */
527 gnuv3_find_method_in (struct type
*domain
, CORE_ADDR voffset
,
532 /* Search this class first. */
537 len
= TYPE_NFN_FIELDS (domain
);
538 for (i
= 0; i
< len
; i
++)
543 f
= TYPE_FN_FIELDLIST1 (domain
, i
);
544 len2
= TYPE_FN_FIELDLIST_LENGTH (domain
, i
);
546 check_stub_method_group (domain
, i
);
547 for (j
= 0; j
< len2
; j
++)
548 if (TYPE_FN_FIELD_VOFFSET (f
, j
) == voffset
)
549 return TYPE_FN_FIELD_PHYSNAME (f
, j
);
553 /* Next search non-virtual bases. If it's in a virtual base,
554 we're out of luck. */
555 for (i
= 0; i
< TYPE_N_BASECLASSES (domain
); i
++)
558 struct type
*basetype
;
560 if (BASETYPE_VIA_VIRTUAL (domain
, i
))
563 pos
= TYPE_BASECLASS_BITPOS (domain
, i
) / 8;
564 basetype
= domain
->field (i
).type ();
565 /* Recurse with a modified adjustment. We don't need to adjust
567 if (adjustment
>= pos
&& adjustment
< pos
+ basetype
->length ())
568 return gnuv3_find_method_in (basetype
, voffset
, adjustment
- pos
);
574 /* Decode GNU v3 method pointer. */
577 gnuv3_decode_method_ptr (struct gdbarch
*gdbarch
,
578 const gdb_byte
*contents
,
580 LONGEST
*adjustment_p
)
582 struct type
*funcptr_type
= builtin_type (gdbarch
)->builtin_func_ptr
;
583 struct type
*offset_type
= vtable_ptrdiff_type (gdbarch
);
584 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
586 LONGEST voffset
, adjustment
;
589 /* Extract the pointer to member. The first element is either a pointer
590 or a vtable offset. For pointers, we need to use extract_typed_address
591 to allow the back-end to convert the pointer to a GDB address -- but
592 vtable offsets we must handle as integers. At this point, we do not
593 yet know which case we have, so we extract the value under both
594 interpretations and choose the right one later on. */
595 ptr_value
= extract_typed_address (contents
, funcptr_type
);
596 voffset
= extract_signed_integer (contents
,
597 funcptr_type
->length (), byte_order
);
598 contents
+= funcptr_type
->length ();
599 adjustment
= extract_signed_integer (contents
,
600 offset_type
->length (), byte_order
);
602 if (!gdbarch_vbit_in_delta (gdbarch
))
605 voffset
= voffset
^ vbit
;
609 vbit
= adjustment
& 1;
610 adjustment
= adjustment
>> 1;
613 *value_p
= vbit
? voffset
: ptr_value
;
614 *adjustment_p
= adjustment
;
618 /* GNU v3 implementation of cplus_print_method_ptr. */
621 gnuv3_print_method_ptr (const gdb_byte
*contents
,
623 struct ui_file
*stream
)
625 struct type
*self_type
= TYPE_SELF_TYPE (type
);
626 struct gdbarch
*gdbarch
= self_type
->arch ();
631 /* Extract the pointer to member. */
632 vbit
= gnuv3_decode_method_ptr (gdbarch
, contents
, &ptr_value
, &adjustment
);
634 /* Check for NULL. */
635 if (ptr_value
== 0 && vbit
== 0)
637 gdb_printf (stream
, "NULL");
641 /* Search for a virtual method. */
645 const char *physname
;
647 /* It's a virtual table offset, maybe in this class. Search
648 for a field with the correct vtable offset. First convert it
649 to an index, as used in TYPE_FN_FIELD_VOFFSET. */
650 voffset
= ptr_value
/ vtable_ptrdiff_type (gdbarch
)->length ();
652 physname
= gnuv3_find_method_in (self_type
, voffset
, adjustment
);
654 /* If we found a method, print that. We don't bother to disambiguate
655 possible paths to the method based on the adjustment. */
658 gdb::unique_xmalloc_ptr
<char> demangled_name
659 = gdb_demangle (physname
, DMGL_ANSI
| DMGL_PARAMS
);
661 gdb_printf (stream
, "&virtual ");
662 if (demangled_name
== NULL
)
663 gdb_puts (physname
, stream
);
665 gdb_puts (demangled_name
.get (), stream
);
669 else if (ptr_value
!= 0)
671 /* Found a non-virtual function: print out the type. */
672 gdb_puts ("(", stream
);
673 c_print_type (type
, "", stream
, -1, 0, current_language
->la_language
,
674 &type_print_raw_options
);
675 gdb_puts (") ", stream
);
678 /* We didn't find it; print the raw data. */
681 gdb_printf (stream
, "&virtual table offset ");
682 print_longest (stream
, 'd', 1, ptr_value
);
686 struct value_print_options opts
;
688 get_user_print_options (&opts
);
689 print_address_demangle (&opts
, gdbarch
, ptr_value
, stream
, demangle
);
694 gdb_printf (stream
, ", this adjustment ");
695 print_longest (stream
, 'd', 1, adjustment
);
699 /* GNU v3 implementation of cplus_method_ptr_size. */
702 gnuv3_method_ptr_size (struct type
*type
)
704 return 2 * builtin_type (type
->arch ())->builtin_data_ptr
->length ();
707 /* GNU v3 implementation of cplus_make_method_ptr. */
710 gnuv3_make_method_ptr (struct type
*type
, gdb_byte
*contents
,
711 CORE_ADDR value
, int is_virtual
)
713 struct gdbarch
*gdbarch
= type
->arch ();
714 int size
= builtin_type (gdbarch
)->builtin_data_ptr
->length ();
715 enum bfd_endian byte_order
= type_byte_order (type
);
717 /* FIXME drow/2006-12-24: The adjustment of "this" is currently
718 always zero, since the method pointer is of the correct type.
719 But if the method pointer came from a base class, this is
720 incorrect - it should be the offset to the base. The best
721 fix might be to create the pointer to member pointing at the
722 base class and cast it to the derived class, but that requires
723 support for adjusting pointers to members when casting them -
724 not currently supported by GDB. */
726 if (!gdbarch_vbit_in_delta (gdbarch
))
728 store_unsigned_integer (contents
, size
, byte_order
, value
| is_virtual
);
729 store_unsigned_integer (contents
+ size
, size
, byte_order
, 0);
733 store_unsigned_integer (contents
, size
, byte_order
, value
);
734 store_unsigned_integer (contents
+ size
, size
, byte_order
, is_virtual
);
738 /* GNU v3 implementation of cplus_method_ptr_to_value. */
740 static struct value
*
741 gnuv3_method_ptr_to_value (struct value
**this_p
, struct value
*method_ptr
)
743 struct gdbarch
*gdbarch
;
744 const gdb_byte
*contents
= method_ptr
->contents ().data ();
746 struct type
*self_type
, *final_type
, *method_type
;
750 self_type
= TYPE_SELF_TYPE (check_typedef (method_ptr
->type ()));
751 final_type
= lookup_pointer_type (self_type
);
753 method_type
= check_typedef (method_ptr
->type ())->target_type ();
755 /* Extract the pointer to member. */
756 gdbarch
= self_type
->arch ();
757 vbit
= gnuv3_decode_method_ptr (gdbarch
, contents
, &ptr_value
, &adjustment
);
759 /* First convert THIS to match the containing type of the pointer to
760 member. This cast may adjust the value of THIS. */
761 *this_p
= value_cast (final_type
, *this_p
);
763 /* Then apply whatever adjustment is necessary. This creates a somewhat
764 strange pointer: it claims to have type FINAL_TYPE, but in fact it
765 might not be a valid FINAL_TYPE. For instance, it might be a
766 base class of FINAL_TYPE. And if it's not the primary base class,
767 then printing it out as a FINAL_TYPE object would produce some pretty
770 But we don't really know the type of the first argument in
771 METHOD_TYPE either, which is why this happens. We can't
772 dereference this later as a FINAL_TYPE, but once we arrive in the
773 called method we'll have debugging information for the type of
774 "this" - and that'll match the value we produce here.
776 You can provoke this case by casting a Base::* to a Derived::*, for
778 *this_p
= value_cast (builtin_type (gdbarch
)->builtin_data_ptr
, *this_p
);
779 *this_p
= value_ptradd (*this_p
, adjustment
);
780 *this_p
= value_cast (final_type
, *this_p
);
786 voffset
= ptr_value
/ vtable_ptrdiff_type (gdbarch
)->length ();
787 return gnuv3_get_virtual_fn (gdbarch
, value_ind (*this_p
),
788 method_type
, voffset
);
791 return value_from_pointer (lookup_pointer_type (method_type
), ptr_value
);
794 /* Objects of this type are stored in a hash table and a vector when
795 printing the vtables for a class. */
797 struct value_and_voffset
799 /* The value representing the object. */
802 /* The maximum vtable offset we've found for any object at this
803 offset in the outermost object. */
807 /* Hash function for value_and_voffset. */
810 hash_value_and_voffset (const void *p
)
812 const struct value_and_voffset
*o
= (const struct value_and_voffset
*) p
;
814 return o
->value
->address () + o
->value
->embedded_offset ();
817 /* Equality function for value_and_voffset. */
820 eq_value_and_voffset (const void *a
, const void *b
)
822 const struct value_and_voffset
*ova
= (const struct value_and_voffset
*) a
;
823 const struct value_and_voffset
*ovb
= (const struct value_and_voffset
*) b
;
825 return (ova
->value
->address () + ova
->value
->embedded_offset ()
826 == ovb
->value
->address () + ovb
->value
->embedded_offset ());
829 /* Comparison function for value_and_voffset. */
832 compare_value_and_voffset (const struct value_and_voffset
*va
,
833 const struct value_and_voffset
*vb
)
835 CORE_ADDR addra
= (va
->value
->address ()
836 + va
->value
->embedded_offset ());
837 CORE_ADDR addrb
= (vb
->value
->address ()
838 + vb
->value
->embedded_offset ());
840 return addra
< addrb
;
843 /* A helper function used when printing vtables. This determines the
844 key (most derived) sub-object at each address and also computes the
845 maximum vtable offset seen for the corresponding vtable. Updates
846 OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if
847 needed. VALUE is the object to examine. */
850 compute_vtable_size (htab_t offset_hash
,
851 std::vector
<value_and_voffset
*> *offset_vec
,
855 struct type
*type
= check_typedef (value
->type ());
857 struct value_and_voffset search_vo
, *current_vo
;
859 gdb_assert (type
->code () == TYPE_CODE_STRUCT
);
861 /* If the object is not dynamic, then we are done; as it cannot have
862 dynamic base types either. */
863 if (!gnuv3_dynamic_class (type
))
866 /* Update the hash and the vec, if needed. */
867 search_vo
.value
= value
;
868 slot
= htab_find_slot (offset_hash
, &search_vo
, INSERT
);
870 current_vo
= (struct value_and_voffset
*) *slot
;
873 current_vo
= XNEW (struct value_and_voffset
);
874 current_vo
->value
= value
;
875 current_vo
->max_voffset
= -1;
877 offset_vec
->push_back (current_vo
);
880 /* Update the value_and_voffset object with the highest vtable
881 offset from this class. */
882 for (i
= 0; i
< TYPE_NFN_FIELDS (type
); ++i
)
885 struct fn_field
*fn
= TYPE_FN_FIELDLIST1 (type
, i
);
887 for (j
= 0; j
< TYPE_FN_FIELDLIST_LENGTH (type
, i
); ++j
)
889 if (TYPE_FN_FIELD_VIRTUAL_P (fn
, j
))
891 int voffset
= TYPE_FN_FIELD_VOFFSET (fn
, j
);
893 if (voffset
> current_vo
->max_voffset
)
894 current_vo
->max_voffset
= voffset
;
899 /* Recurse into base classes. */
900 for (i
= 0; i
< TYPE_N_BASECLASSES (type
); ++i
)
901 compute_vtable_size (offset_hash
, offset_vec
, value_field (value
, i
));
904 /* Helper for gnuv3_print_vtable that prints a single vtable. */
907 print_one_vtable (struct gdbarch
*gdbarch
, struct value
*value
,
909 struct value_print_options
*opts
)
912 struct type
*type
= check_typedef (value
->type ());
913 struct value
*vtable
;
916 vtable
= gnuv3_get_vtable (gdbarch
, type
,
918 + value
->embedded_offset ());
919 vt_addr
= value_field (vtable
,
920 vtable_field_virtual_functions
)->address ();
922 gdb_printf (_("vtable for '%s' @ %s (subobject @ %s):\n"),
923 TYPE_SAFE_NAME (type
),
924 paddress (gdbarch
, vt_addr
),
925 paddress (gdbarch
, (value
->address ()
926 + value
->embedded_offset ())));
928 for (i
= 0; i
<= max_voffset
; ++i
)
930 /* Initialize it just to avoid a GCC false warning. */
935 gdb_printf ("[%d]: ", i
);
937 vfn
= value_subscript (value_field (vtable
,
938 vtable_field_virtual_functions
),
941 if (gdbarch_vtable_function_descriptors (gdbarch
))
942 vfn
= value_addr (vfn
);
946 addr
= value_as_address (vfn
);
948 catch (const gdb_exception_error
&ex
)
950 fprintf_styled (gdb_stdout
, metadata_style
.style (),
951 _("<error: %s>"), ex
.what ());
956 print_function_pointer_address (opts
, gdbarch
, addr
, gdb_stdout
);
961 /* Implementation of the print_vtable method. */
964 gnuv3_print_vtable (struct value
*value
)
966 struct gdbarch
*gdbarch
;
968 struct value
*vtable
;
969 struct value_print_options opts
;
972 value
= coerce_ref (value
);
973 type
= check_typedef (value
->type ());
974 if (type
->code () == TYPE_CODE_PTR
)
976 value
= value_ind (value
);
977 type
= check_typedef (value
->type ());
980 get_user_print_options (&opts
);
982 /* Respect 'set print object'. */
983 if (opts
.objectprint
)
985 value
= value_full_object (value
, NULL
, 0, 0, 0);
986 type
= check_typedef (value
->type ());
989 gdbarch
= type
->arch ();
992 if (type
->code () == TYPE_CODE_STRUCT
)
993 vtable
= gnuv3_get_vtable (gdbarch
, type
,
994 value_as_address (value_addr (value
)));
998 gdb_printf (_("This object does not have a virtual function table\n"));
1002 htab_up
offset_hash (htab_create_alloc (1, hash_value_and_voffset
,
1003 eq_value_and_voffset
,
1004 xfree
, xcalloc
, xfree
));
1005 std::vector
<value_and_voffset
*> result_vec
;
1007 compute_vtable_size (offset_hash
.get (), &result_vec
, value
);
1008 std::sort (result_vec
.begin (), result_vec
.end (),
1009 compare_value_and_voffset
);
1012 for (value_and_voffset
*iter
: result_vec
)
1014 if (iter
->max_voffset
>= 0)
1018 print_one_vtable (gdbarch
, iter
->value
, iter
->max_voffset
, &opts
);
1024 /* Return a GDB type representing `struct std::type_info', laid out
1025 appropriately for ARCH.
1027 We use this function as the gdbarch per-architecture data
1028 initialization function. */
1030 static struct type
*
1031 build_std_type_info_type (struct gdbarch
*arch
)
1035 struct type
*void_ptr_type
1036 = builtin_type (arch
)->builtin_data_ptr
;
1037 struct type
*char_type
1038 = builtin_type (arch
)->builtin_char
;
1039 struct type
*char_ptr_type
1040 = make_pointer_type (make_cv_type (1, 0, char_type
, NULL
), NULL
);
1042 t
= type_allocator (arch
).new_type (TYPE_CODE_STRUCT
, 0, nullptr);
1044 t
->alloc_fields (2);
1050 struct field
&field0
= t
->field (0);
1051 field0
.set_name ("_vptr.type_info");
1052 field0
.set_type (void_ptr_type
);
1053 field0
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
1054 offset
+= field0
.type ()->length ();
1059 struct field
&field1
= t
->field (1);
1060 field1
.set_name ("__name");
1061 field1
.set_type (char_ptr_type
);
1062 field1
.set_loc_bitpos (offset
* TARGET_CHAR_BIT
);
1063 offset
+= field1
.type ()->length ();
1066 t
->set_length (offset
);
1068 t
->set_name ("gdb_gnu_v3_type_info");
1069 INIT_CPLUS_SPECIFIC (t
);
1074 /* Implement the 'get_typeid_type' method. */
1076 static struct type
*
1077 gnuv3_get_typeid_type (struct gdbarch
*gdbarch
)
1079 struct symbol
*typeinfo
;
1080 struct type
*typeinfo_type
;
1082 typeinfo
= lookup_symbol ("std::type_info", NULL
, STRUCT_DOMAIN
,
1084 if (typeinfo
== NULL
)
1086 typeinfo_type
= std_type_info_gdbarch_data
.get (gdbarch
);
1087 if (typeinfo_type
== nullptr)
1089 typeinfo_type
= build_std_type_info_type (gdbarch
);
1090 std_type_info_gdbarch_data
.set (gdbarch
, typeinfo_type
);
1094 typeinfo_type
= typeinfo
->type ();
1096 return typeinfo_type
;
1099 /* Implement the 'get_typeid' method. */
1101 static struct value
*
1102 gnuv3_get_typeid (struct value
*value
)
1104 struct type
*typeinfo_type
;
1106 struct gdbarch
*gdbarch
;
1107 struct value
*result
;
1108 std::string type_name
;
1109 gdb::unique_xmalloc_ptr
<char> canonical
;
1111 /* We have to handle values a bit trickily here, to allow this code
1112 to work properly with non_lvalue values that are really just
1114 if (value
->lval () == lval_memory
)
1115 value
= coerce_ref (value
);
1117 type
= check_typedef (value
->type ());
1119 /* In the non_lvalue case, a reference might have slipped through
1121 if (type
->code () == TYPE_CODE_REF
)
1122 type
= check_typedef (type
->target_type ());
1124 /* Ignore top-level cv-qualifiers. */
1125 type
= make_cv_type (0, 0, type
, NULL
);
1126 gdbarch
= type
->arch ();
1128 type_name
= type_to_string (type
);
1129 if (type_name
.empty ())
1130 error (_("cannot find typeinfo for unnamed type"));
1132 /* We need to canonicalize the type name here, because we do lookups
1133 using the demangled name, and so we must match the format it
1134 uses. E.g., GDB tends to use "const char *" as a type name, but
1135 the demangler uses "char const *". */
1136 canonical
= cp_canonicalize_string (type_name
.c_str ());
1137 const char *name
= (canonical
== nullptr
1138 ? type_name
.c_str ()
1139 : canonical
.get ());
1141 typeinfo_type
= gnuv3_get_typeid_type (gdbarch
);
1143 /* We check for lval_memory because in the "typeid (type-id)" case,
1144 the type is passed via a not_lval value object. */
1145 if (type
->code () == TYPE_CODE_STRUCT
1146 && value
->lval () == lval_memory
1147 && gnuv3_dynamic_class (type
))
1149 struct value
*vtable
, *typeinfo_value
;
1150 CORE_ADDR address
= value
->address () + value
->embedded_offset ();
1152 vtable
= gnuv3_get_vtable (gdbarch
, type
, address
);
1154 error (_("cannot find typeinfo for object of type '%s'"),
1156 typeinfo_value
= value_field (vtable
, vtable_field_type_info
);
1157 result
= value_ind (value_cast (make_pointer_type (typeinfo_type
, NULL
),
1162 std::string sym_name
= std::string ("typeinfo for ") + name
;
1163 bound_minimal_symbol minsym
1164 = lookup_minimal_symbol (sym_name
.c_str (), NULL
, NULL
);
1166 if (minsym
.minsym
== NULL
)
1167 error (_("could not find typeinfo symbol for '%s'"), name
);
1169 result
= value_at_lazy (typeinfo_type
, minsym
.value_address ());
1175 /* Implement the 'get_typename_from_type_info' method. */
1178 gnuv3_get_typename_from_type_info (struct value
*type_info_ptr
)
1180 struct gdbarch
*gdbarch
= type_info_ptr
->type ()->arch ();
1181 struct bound_minimal_symbol typeinfo_sym
;
1183 const char *symname
;
1184 const char *class_name
;
1187 addr
= value_as_address (type_info_ptr
);
1188 typeinfo_sym
= lookup_minimal_symbol_by_pc (addr
);
1189 if (typeinfo_sym
.minsym
== NULL
)
1190 error (_("could not find minimal symbol for typeinfo address %s"),
1191 paddress (gdbarch
, addr
));
1193 #define TYPEINFO_PREFIX "typeinfo for "
1194 #define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1)
1195 symname
= typeinfo_sym
.minsym
->demangled_name ();
1196 if (symname
== NULL
|| strncmp (symname
, TYPEINFO_PREFIX
,
1197 TYPEINFO_PREFIX_LEN
))
1198 error (_("typeinfo symbol '%s' has unexpected name"),
1199 typeinfo_sym
.minsym
->linkage_name ());
1200 class_name
= symname
+ TYPEINFO_PREFIX_LEN
;
1202 /* Strip off @plt and version suffixes. */
1203 atsign
= strchr (class_name
, '@');
1205 return std::string (class_name
, atsign
- class_name
);
1209 /* Implement the 'get_type_from_type_info' method. */
1211 static struct type
*
1212 gnuv3_get_type_from_type_info (struct value
*type_info_ptr
)
1214 /* We have to parse the type name, since in general there is not a
1215 symbol for a type. This is somewhat bogus since there may be a
1216 mis-parse. Another approach might be to re-use the demangler's
1217 internal form to reconstruct the type somehow. */
1218 std::string type_name
= gnuv3_get_typename_from_type_info (type_info_ptr
);
1219 expression_up
expr (parse_expression (type_name
.c_str ()));
1220 struct value
*type_val
= expr
->evaluate_type ();
1221 return type_val
->type ();
1224 /* Determine if we are currently in a C++ thunk. If so, get the address
1225 of the routine we are thunking to and continue to there instead. */
1228 gnuv3_skip_trampoline (frame_info_ptr frame
, CORE_ADDR stop_pc
)
1230 CORE_ADDR real_stop_pc
, method_stop_pc
, func_addr
;
1231 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
1232 struct bound_minimal_symbol thunk_sym
, fn_sym
;
1233 struct obj_section
*section
;
1234 const char *thunk_name
, *fn_name
;
1236 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
1237 if (real_stop_pc
== 0)
1238 real_stop_pc
= stop_pc
;
1240 /* Find the linker symbol for this potential thunk. */
1241 thunk_sym
= lookup_minimal_symbol_by_pc (real_stop_pc
);
1242 section
= find_pc_section (real_stop_pc
);
1243 if (thunk_sym
.minsym
== NULL
|| section
== NULL
)
1246 /* The symbol's demangled name should be something like "virtual
1247 thunk to FUNCTION", where FUNCTION is the name of the function
1248 being thunked to. */
1249 thunk_name
= thunk_sym
.minsym
->demangled_name ();
1250 if (thunk_name
== NULL
|| strstr (thunk_name
, " thunk to ") == NULL
)
1253 fn_name
= strstr (thunk_name
, " thunk to ") + strlen (" thunk to ");
1254 fn_sym
= lookup_minimal_symbol (fn_name
, NULL
, section
->objfile
);
1255 if (fn_sym
.minsym
== NULL
)
1258 method_stop_pc
= fn_sym
.value_address ();
1260 /* Some targets have minimal symbols pointing to function descriptors
1261 (powerpc 64 for example). Make sure to retrieve the address
1262 of the real function from the function descriptor before passing on
1263 the address to other layers of GDB. */
1264 func_addr
= gdbarch_convert_from_func_ptr_addr
1265 (gdbarch
, method_stop_pc
, current_inferior ()->top_target ());
1267 method_stop_pc
= func_addr
;
1269 real_stop_pc
= gdbarch_skip_trampoline_code
1270 (gdbarch
, frame
, method_stop_pc
);
1271 if (real_stop_pc
== 0)
1272 real_stop_pc
= method_stop_pc
;
1274 return real_stop_pc
;
1277 /* A member function is in one these states. */
1279 enum definition_style
1281 DOES_NOT_EXIST_IN_SOURCE
,
1288 /* Return how the given field is defined. */
1290 static definition_style
1291 get_def_style (struct fn_field
*fn
, int fieldelem
)
1293 if (TYPE_FN_FIELD_DELETED (fn
, fieldelem
))
1296 if (TYPE_FN_FIELD_ARTIFICIAL (fn
, fieldelem
))
1297 return DOES_NOT_EXIST_IN_SOURCE
;
1299 switch (TYPE_FN_FIELD_DEFAULTED (fn
, fieldelem
))
1301 case DW_DEFAULTED_no
:
1303 case DW_DEFAULTED_in_class
:
1304 return DEFAULTED_INSIDE
;
1305 case DW_DEFAULTED_out_of_class
:
1306 return DEFAULTED_OUTSIDE
;
1314 /* Helper functions to determine whether the given definition style
1315 denotes that the definition is user-provided or implicit.
1316 Being defaulted outside the class decl counts as an explicit
1317 user-definition, while being defaulted inside is implicit. */
1320 is_user_provided_def (definition_style def
)
1322 return def
== EXPLICIT
|| def
== DEFAULTED_OUTSIDE
;
1326 is_implicit_def (definition_style def
)
1328 return def
== DOES_NOT_EXIST_IN_SOURCE
|| def
== DEFAULTED_INSIDE
;
1331 /* Helper function to decide if METHOD_TYPE is a copy/move
1332 constructor type for CLASS_TYPE. EXPECTED is the expected
1333 type code for the "right-hand-side" argument.
1334 This function is supposed to be used by the IS_COPY_CONSTRUCTOR_TYPE
1335 and IS_MOVE_CONSTRUCTOR_TYPE functions below. Normally, you should
1336 not need to call this directly. */
1339 is_copy_or_move_constructor_type (struct type
*class_type
,
1340 struct type
*method_type
,
1343 /* The method should take at least two arguments... */
1344 if (method_type
->num_fields () < 2)
1347 /* ...and the second argument should be the same as the class
1348 type, with the expected type code... */
1349 struct type
*arg_type
= method_type
->field (1).type ();
1351 if (arg_type
->code () != expected
)
1354 struct type
*target
= check_typedef (arg_type
->target_type ());
1355 if (!(class_types_same_p (target
, class_type
)))
1358 /* ...and if any of the remaining arguments don't have a default value
1359 then this is not a copy or move constructor, but just a
1361 for (int i
= 2; i
< method_type
->num_fields (); i
++)
1363 arg_type
= method_type
->field (i
).type ();
1364 /* FIXME aktemur/2019-10-31: As of this date, neither
1365 clang++-7.0.0 nor g++-8.2.0 produce a DW_AT_default_value
1366 attribute. GDB is also not set to read this attribute, yet.
1367 Hence, we immediately return false if there are more than
1370 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42959
1378 /* Return true if METHOD_TYPE is a copy ctor type for CLASS_TYPE. */
1381 is_copy_constructor_type (struct type
*class_type
,
1382 struct type
*method_type
)
1384 return is_copy_or_move_constructor_type (class_type
, method_type
,
1388 /* Return true if METHOD_TYPE is a move ctor type for CLASS_TYPE. */
1391 is_move_constructor_type (struct type
*class_type
,
1392 struct type
*method_type
)
1394 return is_copy_or_move_constructor_type (class_type
, method_type
,
1395 TYPE_CODE_RVALUE_REF
);
1398 /* Return pass-by-reference information for the given TYPE.
1400 The rule in the v3 ABI document comes from section 3.1.1. If the
1401 type has a non-trivial copy constructor or destructor, then the
1402 caller must make a copy (by calling the copy constructor if there
1403 is one or perform the copy itself otherwise), pass the address of
1404 the copy, and then destroy the temporary (if necessary).
1406 For return values with non-trivial copy/move constructors or
1407 destructors, space will be allocated in the caller, and a pointer
1408 will be passed as the first argument (preceding "this").
1410 We don't have a bulletproof mechanism for determining whether a
1411 constructor or destructor is trivial. For GCC and DWARF5 debug
1412 information, we can check the calling_convention attribute,
1413 the 'artificial' flag, the 'defaulted' attribute, and the
1414 'deleted' attribute. */
1416 static struct language_pass_by_ref_info
1417 gnuv3_pass_by_reference (struct type
*type
)
1419 int fieldnum
, fieldelem
;
1421 type
= check_typedef (type
);
1423 /* Start with the default values. */
1424 struct language_pass_by_ref_info info
;
1426 bool has_cc_attr
= false;
1427 bool is_pass_by_value
= false;
1428 bool is_dynamic
= false;
1429 definition_style cctor_def
= DOES_NOT_EXIST_IN_SOURCE
;
1430 definition_style dtor_def
= DOES_NOT_EXIST_IN_SOURCE
;
1431 definition_style mctor_def
= DOES_NOT_EXIST_IN_SOURCE
;
1433 /* We're only interested in things that can have methods. */
1434 if (type
->code () != TYPE_CODE_STRUCT
1435 && type
->code () != TYPE_CODE_UNION
)
1438 /* The compiler may have emitted the calling convention attribute.
1439 Note: GCC does not produce this attribute as of version 9.2.1.
1440 Bug link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92418 */
1441 if (TYPE_CPLUS_CALLING_CONVENTION (type
) == DW_CC_pass_by_value
)
1444 is_pass_by_value
= true;
1445 /* Do not return immediately. We have to find out if this type
1446 is copy_constructible and destructible. */
1449 if (TYPE_CPLUS_CALLING_CONVENTION (type
) == DW_CC_pass_by_reference
)
1452 is_pass_by_value
= false;
1455 /* A dynamic class has a non-trivial copy constructor.
1456 See c++98 section 12.8 Copying class objects [class.copy]. */
1457 if (gnuv3_dynamic_class (type
))
1460 for (fieldnum
= 0; fieldnum
< TYPE_NFN_FIELDS (type
); fieldnum
++)
1461 for (fieldelem
= 0; fieldelem
< TYPE_FN_FIELDLIST_LENGTH (type
, fieldnum
);
1464 struct fn_field
*fn
= TYPE_FN_FIELDLIST1 (type
, fieldnum
);
1465 const char *name
= TYPE_FN_FIELDLIST_NAME (type
, fieldnum
);
1466 struct type
*fieldtype
= TYPE_FN_FIELD_TYPE (fn
, fieldelem
);
1470 /* We've found a destructor.
1471 There should be at most one dtor definition. */
1472 gdb_assert (dtor_def
== DOES_NOT_EXIST_IN_SOURCE
);
1473 dtor_def
= get_def_style (fn
, fieldelem
);
1475 else if (is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn
, fieldelem
))
1476 || TYPE_FN_FIELD_CONSTRUCTOR (fn
, fieldelem
))
1478 /* FIXME drow/2007-09-23: We could do this using the name of
1479 the method and the name of the class instead of dealing
1480 with the mangled name. We don't have a convenient function
1481 to strip off both leading scope qualifiers and trailing
1482 template arguments yet. */
1483 if (is_copy_constructor_type (type
, fieldtype
))
1485 /* There may be more than one cctors. E.g.: one that
1486 take a const parameter and another that takes a
1487 non-const parameter. Such as:
1494 It is sufficient for the type to be non-trivial
1495 even only one of the cctors is explicit.
1496 Therefore, update the cctor_def value in the
1497 implicit -> explicit direction, not backwards. */
1499 if (is_implicit_def (cctor_def
))
1500 cctor_def
= get_def_style (fn
, fieldelem
);
1502 else if (is_move_constructor_type (type
, fieldtype
))
1504 /* Again, there may be multiple move ctors. Update the
1505 mctor_def value if we found an explicit def and the
1506 existing one is not explicit. Otherwise retain the
1508 if (is_implicit_def (mctor_def
))
1509 mctor_def
= get_def_style (fn
, fieldelem
);
1514 bool cctor_implicitly_deleted
1515 = (mctor_def
!= DOES_NOT_EXIST_IN_SOURCE
1516 && cctor_def
== DOES_NOT_EXIST_IN_SOURCE
);
1518 bool cctor_explicitly_deleted
= (cctor_def
== DELETED
);
1520 if (cctor_implicitly_deleted
|| cctor_explicitly_deleted
)
1521 info
.copy_constructible
= false;
1523 if (dtor_def
== DELETED
)
1524 info
.destructible
= false;
1526 info
.trivially_destructible
= is_implicit_def (dtor_def
);
1528 info
.trivially_copy_constructible
1529 = (is_implicit_def (cctor_def
)
1532 info
.trivially_copyable
1533 = (info
.trivially_copy_constructible
1534 && info
.trivially_destructible
1535 && !is_user_provided_def (mctor_def
));
1537 /* Even if all the constructors and destructors were artificial, one
1538 of them may have invoked a non-artificial constructor or
1539 destructor in a base class. If any base class needs to be passed
1540 by reference, so does this class. Similarly for members, which
1541 are constructed whenever this class is. We do not need to worry
1542 about recursive loops here, since we are only looking at members
1543 of complete class type. Also ignore any static members. */
1544 for (fieldnum
= 0; fieldnum
< type
->num_fields (); fieldnum
++)
1545 if (!type
->field (fieldnum
).is_static ())
1547 struct type
*field_type
= type
->field (fieldnum
).type ();
1549 /* For arrays, make the decision based on the element type. */
1550 if (field_type
->code () == TYPE_CODE_ARRAY
)
1551 field_type
= check_typedef (field_type
->target_type ());
1553 struct language_pass_by_ref_info field_info
1554 = gnuv3_pass_by_reference (field_type
);
1556 if (!field_info
.copy_constructible
)
1557 info
.copy_constructible
= false;
1558 if (!field_info
.destructible
)
1559 info
.destructible
= false;
1560 if (!field_info
.trivially_copyable
)
1561 info
.trivially_copyable
= false;
1562 if (!field_info
.trivially_copy_constructible
)
1563 info
.trivially_copy_constructible
= false;
1564 if (!field_info
.trivially_destructible
)
1565 info
.trivially_destructible
= false;
1568 /* Consistency check. */
1569 if (has_cc_attr
&& info
.trivially_copyable
!= is_pass_by_value
)
1571 /* DWARF CC attribute is not the same as the inferred value;
1572 use the DWARF attribute. */
1573 info
.trivially_copyable
= is_pass_by_value
;
1580 init_gnuv3_ops (void)
1582 gnu_v3_abi_ops
.shortname
= "gnu-v3";
1583 gnu_v3_abi_ops
.longname
= "GNU G++ Version 3 ABI";
1584 gnu_v3_abi_ops
.doc
= "G++ Version 3 ABI";
1585 gnu_v3_abi_ops
.is_destructor_name
=
1586 (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor
;
1587 gnu_v3_abi_ops
.is_constructor_name
=
1588 (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor
;
1589 gnu_v3_abi_ops
.is_vtable_name
= gnuv3_is_vtable_name
;
1590 gnu_v3_abi_ops
.is_operator_name
= gnuv3_is_operator_name
;
1591 gnu_v3_abi_ops
.rtti_type
= gnuv3_rtti_type
;
1592 gnu_v3_abi_ops
.virtual_fn_field
= gnuv3_virtual_fn_field
;
1593 gnu_v3_abi_ops
.baseclass_offset
= gnuv3_baseclass_offset
;
1594 gnu_v3_abi_ops
.print_method_ptr
= gnuv3_print_method_ptr
;
1595 gnu_v3_abi_ops
.method_ptr_size
= gnuv3_method_ptr_size
;
1596 gnu_v3_abi_ops
.make_method_ptr
= gnuv3_make_method_ptr
;
1597 gnu_v3_abi_ops
.method_ptr_to_value
= gnuv3_method_ptr_to_value
;
1598 gnu_v3_abi_ops
.print_vtable
= gnuv3_print_vtable
;
1599 gnu_v3_abi_ops
.get_typeid
= gnuv3_get_typeid
;
1600 gnu_v3_abi_ops
.get_typeid_type
= gnuv3_get_typeid_type
;
1601 gnu_v3_abi_ops
.get_type_from_type_info
= gnuv3_get_type_from_type_info
;
1602 gnu_v3_abi_ops
.get_typename_from_type_info
1603 = gnuv3_get_typename_from_type_info
;
1604 gnu_v3_abi_ops
.skip_trampoline
= gnuv3_skip_trampoline
;
1605 gnu_v3_abi_ops
.pass_by_reference
= gnuv3_pass_by_reference
;
1608 void _initialize_gnu_v3_abi ();
1610 _initialize_gnu_v3_abi ()
1614 register_cp_abi (&gnu_v3_abi_ops
);
1615 set_cp_abi_as_auto_default (gnu_v3_abi_ops
.shortname
);