+/* GNU v3 implementation of value_virtual_fn_field. See cp-abi.h
+ for a description of the arguments. */
+
+static struct value *
+gnuv3_virtual_fn_field (struct value **value_p,
+ struct fn_field *f, int j,
+ struct type *vfn_base, int offset)
+{
+ struct type *values_type = check_typedef (value_type (*value_p));
+
+ /* Some simple sanity checks. */
+ if (TYPE_CODE (values_type) != TYPE_CODE_CLASS)
+ error (_("Only classes can have virtual functions."));
+
+ /* Cast our value to the base class which defines this virtual
+ function. This takes care of any necessary `this'
+ adjustments. */
+ if (vfn_base != values_type)
+ *value_p = value_cast (vfn_base, *value_p);
+
+ return gnuv3_get_virtual_fn (*value_p, TYPE_FN_FIELD_TYPE (f, j),
+ TYPE_FN_FIELD_VOFFSET (f, j));
+}
+
+/* Compute the offset of the baseclass which is
+ the INDEXth baseclass of class TYPE,
+ for value at VALADDR (in host) at ADDRESS (in target).
+ The result is the offset of the baseclass value relative
+ to (the address of)(ARG) + OFFSET.
+
+ -1 is returned on error. */
+static int
+gnuv3_baseclass_offset (struct type *type, int index, const bfd_byte *valaddr,
+ CORE_ADDR address)
+{
+ struct type *vtable_type = gdbarch_data (current_gdbarch,
+ vtable_type_gdbarch_data);
+ struct value *vtable;
+ struct type *vbasetype;
+ struct value *offset_val, *vbase_array;
+ CORE_ADDR vtable_address;
+ long int cur_base_offset, base_offset;
+
+ /* If it isn't a virtual base, this is easy. The offset is in the
+ type definition. */
+ if (!BASETYPE_VIA_VIRTUAL (type, index))
+ return TYPE_BASECLASS_BITPOS (type, index) / 8;
+
+ /* To access a virtual base, we need to use the vbase offset stored in
+ our vtable. Recent GCC versions provide this information. If it isn't
+ available, we could get what we needed from RTTI, or from drawing the
+ complete inheritance graph based on the debug info. Neither is
+ worthwhile. */
+ cur_base_offset = TYPE_BASECLASS_BITPOS (type, index) / 8;
+ if (cur_base_offset >= - vtable_address_point_offset ())
+ error (_("Expected a negative vbase offset (old compiler?)"));
+
+ cur_base_offset = cur_base_offset + vtable_address_point_offset ();
+ if ((- cur_base_offset) % TYPE_LENGTH (builtin_type_void_data_ptr) != 0)
+ error (_("Misaligned vbase offset."));
+ cur_base_offset = cur_base_offset
+ / ((int) TYPE_LENGTH (builtin_type_void_data_ptr));
+
+ /* We're now looking for the cur_base_offset'th entry (negative index)
+ in the vcall_and_vbase_offsets array. We used to cast the object to
+ its TYPE_VPTR_BASETYPE, and reference the vtable as TYPE_VPTR_FIELDNO;
+ however, that cast can not be done without calling baseclass_offset again
+ if the TYPE_VPTR_BASETYPE is a virtual base class, as described in the
+ v3 C++ ABI Section 2.4.I.2.b. Fortunately the ABI guarantees that the
+ vtable pointer will be located at the beginning of the object, so we can
+ bypass the casting. Verify that the TYPE_VPTR_FIELDNO is in fact at the
+ start of whichever baseclass it resides in, as a sanity measure - iff
+ we have debugging information for that baseclass. */
+
+ vbasetype = TYPE_VPTR_BASETYPE (type);
+ if (TYPE_VPTR_FIELDNO (vbasetype) < 0)
+ fill_in_vptr_fieldno (vbasetype);
+
+ if (TYPE_VPTR_FIELDNO (vbasetype) >= 0
+ && TYPE_FIELD_BITPOS (vbasetype, TYPE_VPTR_FIELDNO (vbasetype)) != 0)
+ error (_("Illegal vptr offset in class %s"),
+ TYPE_NAME (vbasetype) ? TYPE_NAME (vbasetype) : "<unknown>");
+
+ vtable_address = value_as_address (value_at_lazy (builtin_type_void_data_ptr,
+ address));
+ vtable = value_at_lazy (vtable_type,
+ vtable_address - vtable_address_point_offset ());
+ offset_val = value_from_longest(builtin_type_int, cur_base_offset);
+ vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets);
+ base_offset = value_as_long (value_subscript (vbase_array, offset_val));
+ return base_offset;
+}
+
+/* Locate a virtual method in DOMAIN or its non-virtual base classes
+ which has virtual table index VOFFSET. The method has an associated
+ "this" adjustment of ADJUSTMENT bytes. */
+
+const char *
+gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset,
+ LONGEST adjustment)
+{
+ int i;
+ const char *physname;
+
+ /* Search this class first. */
+ physname = NULL;
+ if (adjustment == 0)
+ {
+ int len;
+
+ len = TYPE_NFN_FIELDS (domain);
+ for (i = 0; i < len; i++)
+ {
+ int len2, j;
+ struct fn_field *f;
+
+ f = TYPE_FN_FIELDLIST1 (domain, i);
+ len2 = TYPE_FN_FIELDLIST_LENGTH (domain, i);
+
+ check_stub_method_group (domain, i);
+ for (j = 0; j < len2; j++)
+ if (TYPE_FN_FIELD_VOFFSET (f, j) == voffset)
+ return TYPE_FN_FIELD_PHYSNAME (f, j);
+ }
+ }
+
+ /* Next search non-virtual bases. If it's in a virtual base,
+ we're out of luck. */
+ for (i = 0; i < TYPE_N_BASECLASSES (domain); i++)
+ {
+ int pos;
+ struct type *basetype;
+
+ if (BASETYPE_VIA_VIRTUAL (domain, i))
+ continue;
+
+ pos = TYPE_BASECLASS_BITPOS (domain, i) / 8;
+ basetype = TYPE_FIELD_TYPE (domain, i);
+ /* Recurse with a modified adjustment. We don't need to adjust
+ voffset. */
+ if (adjustment >= pos && adjustment < pos + TYPE_LENGTH (basetype))
+ return gnuv3_find_method_in (basetype, voffset, adjustment - pos);
+ }
+
+ return NULL;
+}
+
+/* GNU v3 implementation of cplus_print_method_ptr. */
+
+static void
+gnuv3_print_method_ptr (const gdb_byte *contents,
+ struct type *type,
+ struct ui_file *stream)
+{
+ CORE_ADDR ptr_value;
+ LONGEST adjustment;
+ struct type *domain;
+ int vbit;
+
+ domain = TYPE_DOMAIN_TYPE (type);
+
+ /* Extract the pointer to member. */
+ ptr_value = extract_typed_address (contents, builtin_type_void_func_ptr);
+ contents += TYPE_LENGTH (builtin_type_void_func_ptr);
+ adjustment = extract_signed_integer (contents,
+ TYPE_LENGTH (builtin_type_long));
+
+ if (!gdbarch_vbit_in_delta (current_gdbarch))
+ {
+ vbit = ptr_value & 1;
+ ptr_value = ptr_value ^ vbit;
+ }
+ else
+ {
+ vbit = adjustment & 1;
+ adjustment = adjustment >> 1;
+ }
+
+ /* Check for NULL. */
+ if (ptr_value == 0 && vbit == 0)
+ {
+ fprintf_filtered (stream, "NULL");
+ return;
+ }
+
+ /* Search for a virtual method. */
+ if (vbit)
+ {
+ CORE_ADDR voffset;
+ const char *physname;
+
+ /* It's a virtual table offset, maybe in this class. Search
+ for a field with the correct vtable offset. First convert it
+ to an index, as used in TYPE_FN_FIELD_VOFFSET. */
+ voffset = ptr_value / TYPE_LENGTH (builtin_type_long);
+
+ physname = gnuv3_find_method_in (domain, voffset, adjustment);
+
+ /* If we found a method, print that. We don't bother to disambiguate
+ possible paths to the method based on the adjustment. */
+ if (physname)
+ {
+ char *demangled_name = cplus_demangle (physname,
+ DMGL_ANSI | DMGL_PARAMS);
+ if (demangled_name != NULL)
+ {
+ fprintf_filtered (stream, "&virtual ");
+ fputs_filtered (demangled_name, stream);
+ xfree (demangled_name);
+ return;
+ }
+ }
+ }
+
+ /* We didn't find it; print the raw data. */
+ if (vbit)
+ {
+ fprintf_filtered (stream, "&virtual table offset ");
+ print_longest (stream, 'd', 1, ptr_value);
+ }
+ else
+ print_address_demangle (ptr_value, stream, demangle);
+
+ if (adjustment)
+ {
+ fprintf_filtered (stream, ", this adjustment ");
+ print_longest (stream, 'd', 1, adjustment);
+ }
+}
+
+/* GNU v3 implementation of cplus_method_ptr_size. */
+
+static int
+gnuv3_method_ptr_size (void)
+{
+ return 2 * TYPE_LENGTH (builtin_type_void_data_ptr);
+}
+
+/* GNU v3 implementation of cplus_make_method_ptr. */
+
+static void
+gnuv3_make_method_ptr (gdb_byte *contents, CORE_ADDR value, int is_virtual)
+{
+ int size = TYPE_LENGTH (builtin_type_void_data_ptr);
+
+ /* FIXME drow/2006-12-24: The adjustment of "this" is currently
+ always zero, since the method pointer is of the correct type.
+ But if the method pointer came from a base class, this is
+ incorrect - it should be the offset to the base. The best
+ fix might be to create the pointer to member pointing at the
+ base class and cast it to the derived class, but that requires
+ support for adjusting pointers to members when casting them -
+ not currently supported by GDB. */
+
+ if (!gdbarch_vbit_in_delta (current_gdbarch))
+ {
+ store_unsigned_integer (contents, size, value | is_virtual);
+ store_unsigned_integer (contents + size, size, 0);
+ }
+ else
+ {
+ store_unsigned_integer (contents, size, value);
+ store_unsigned_integer (contents + size, size, is_virtual);
+ }
+}
+
+/* GNU v3 implementation of cplus_method_ptr_to_value. */
+
+static struct value *
+gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
+{
+ const gdb_byte *contents = value_contents (method_ptr);
+ CORE_ADDR ptr_value;
+ struct type *final_type, *method_type;
+ LONGEST adjustment;
+ struct value *adjval;
+ int vbit;
+
+ final_type = TYPE_DOMAIN_TYPE (check_typedef (value_type (method_ptr)));
+ final_type = lookup_pointer_type (final_type);
+
+ method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
+
+ ptr_value = extract_typed_address (contents, builtin_type_void_func_ptr);
+ contents += TYPE_LENGTH (builtin_type_void_func_ptr);
+ adjustment = extract_signed_integer (contents,
+ TYPE_LENGTH (builtin_type_long));
+
+ if (!gdbarch_vbit_in_delta (current_gdbarch))
+ {
+ vbit = ptr_value & 1;
+ ptr_value = ptr_value ^ vbit;
+ }
+ else
+ {
+ vbit = adjustment & 1;
+ adjustment = adjustment >> 1;
+ }
+
+ /* First convert THIS to match the containing type of the pointer to
+ member. This cast may adjust the value of THIS. */
+ *this_p = value_cast (final_type, *this_p);
+
+ /* Then apply whatever adjustment is necessary. This creates a somewhat
+ strange pointer: it claims to have type FINAL_TYPE, but in fact it
+ might not be a valid FINAL_TYPE. For instance, it might be a
+ base class of FINAL_TYPE. And if it's not the primary base class,
+ then printing it out as a FINAL_TYPE object would produce some pretty
+ garbage.
+
+ But we don't really know the type of the first argument in
+ METHOD_TYPE either, which is why this happens. We can't
+ dereference this later as a FINAL_TYPE, but once we arrive in the
+ called method we'll have debugging information for the type of
+ "this" - and that'll match the value we produce here.
+
+ You can provoke this case by casting a Base::* to a Derived::*, for
+ instance. */
+ *this_p = value_cast (builtin_type_void_data_ptr, *this_p);
+ adjval = value_from_longest (builtin_type_long, adjustment);
+ *this_p = value_add (*this_p, adjval);
+ *this_p = value_cast (final_type, *this_p);
+
+ if (vbit)
+ {
+ LONGEST voffset = ptr_value / TYPE_LENGTH (builtin_type_long);
+ return gnuv3_get_virtual_fn (value_ind (*this_p), method_type, voffset);
+ }
+ else
+ return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
+}
+
+/* Determine if we are currently in a C++ thunk. If so, get the address
+ of the routine we are thunking to and continue to there instead. */
+
+static CORE_ADDR
+gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc)
+{
+ CORE_ADDR real_stop_pc, method_stop_pc;
+ struct minimal_symbol *thunk_sym, *fn_sym;
+ struct obj_section *section;
+ char *thunk_name, *fn_name;
+
+ real_stop_pc = gdbarch_skip_trampoline_code
+ (current_gdbarch, frame, stop_pc);
+ if (real_stop_pc == 0)
+ real_stop_pc = stop_pc;
+
+ /* Find the linker symbol for this potential thunk. */
+ thunk_sym = lookup_minimal_symbol_by_pc (real_stop_pc);
+ section = find_pc_section (real_stop_pc);
+ if (thunk_sym == NULL || section == NULL)
+ return 0;
+
+ /* The symbol's demangled name should be something like "virtual
+ thunk to FUNCTION", where FUNCTION is the name of the function
+ being thunked to. */
+ thunk_name = SYMBOL_DEMANGLED_NAME (thunk_sym);
+ if (thunk_name == NULL || strstr (thunk_name, " thunk to ") == NULL)
+ return 0;
+
+ fn_name = strstr (thunk_name, " thunk to ") + strlen (" thunk to ");
+ fn_sym = lookup_minimal_symbol (fn_name, NULL, section->objfile);
+ if (fn_sym == NULL)
+ return 0;
+
+ method_stop_pc = SYMBOL_VALUE_ADDRESS (fn_sym);
+ real_stop_pc = gdbarch_skip_trampoline_code
+ (current_gdbarch, frame, method_stop_pc);
+ if (real_stop_pc == 0)
+ real_stop_pc = method_stop_pc;
+
+ return real_stop_pc;
+}