static struct value *
gnuv3_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
{
struct gdbarch *gdbarch;
const gdb_byte *contents = value_contents (method_ptr);
CORE_ADDR ptr_value;
struct type *domain_type, *final_type, *method_type;
LONGEST adjustment;
struct value *adjval;
int vbit;
domain_type = TYPE_DOMAIN_TYPE (check_typedef (value_type (method_ptr)));
final_type = lookup_pointer_type (domain_type);
method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
/* Extract the pointer to member. */
gdbarch = get_class_arch (domain_type);
vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
/* 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 (gdbarch)->builtin_data_ptr, *this_p);
adjval = value_from_longest (builtin_type (gdbarch)->builtin_long,
adjustment);
*this_p = value_ptradd (*this_p, adjval);
*this_p = value_cast (final_type, *this_p);
if (vbit)
{
LONGEST voffset;
voffset = ptr_value / TYPE_LENGTH (vtable_ptrdiff_type (gdbarch));
return gnuv3_get_virtual_fn (gdbarch, value_ind (*this_p),
method_type, voffset);
}
else
return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
}
static int
gnuv3_decode_method_ptr (struct gdbarch *gdbarch,
const gdb_byte *contents,
CORE_ADDR *value_p,
LONGEST *adjustment_p)
{
struct type *funcptr_type = builtin_type (gdbarch)->builtin_func_ptr;
struct type *offset_type = vtable_ptrdiff_type (gdbarch);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR ptr_value;
LONGEST voffset, adjustment;
int vbit;
/* Extract the pointer to member. The first element is either a pointer
or a vtable offset. For pointers, we need to use extract_typed_address
to allow the back-end to convert the pointer to a GDB address -- but
vtable offsets we must handle as integers. At this point, we do not
yet know which case we have, so we extract the value under both
interpretations and choose the right one later on. */
ptr_value = extract_typed_address (contents, funcptr_type);
voffset = extract_signed_integer (contents,
TYPE_LENGTH (funcptr_type), byte_order);
contents += TYPE_LENGTH (funcptr_type);
adjustment = extract_signed_integer (contents,
TYPE_LENGTH (offset_type), byte_order);
if (!gdbarch_vbit_in_delta (gdbarch))
{
vbit = voffset & 1;
voffset = voffset ^ vbit;
}
else
{
vbit = adjustment & 1;
adjustment = adjustment >> 1;
}
*value_p = vbit? voffset : ptr_value;
*adjustment_p = adjustment;
return vbit;
}
static void
gnuv3_print_method_ptr (const gdb_byte *contents,
struct type *type,
struct ui_file *stream)
{
struct type *domain = TYPE_DOMAIN_TYPE (type);
struct gdbarch *gdbarch = get_type_arch (domain);
CORE_ADDR ptr_value;
LONGEST adjustment;
int vbit;
/* Extract the pointer to member. */
vbit = gnuv3_decode_method_ptr (gdbarch, contents, &ptr_value, &adjustment);
/* 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 (vtable_ptrdiff_type (gdbarch));
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 = gdb_demangle (physname,
DMGL_ANSI | DMGL_PARAMS);
fprintf_filtered (stream, "&virtual ");
if (demangled_name == NULL)
fputs_filtered (physname, stream);
else
{
fputs_filtered (demangled_name, stream);
xfree (demangled_name);
}
return;
}
}
else if (ptr_value != 0)
{
/* Found a non-virtual function: print out the type. */
fputs_filtered ("(", stream);
c_print_type (type, "", stream, -1, 0, &type_print_raw_options);
fputs_filtered (") ", stream);
}
/* 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
{
struct value_print_options opts;
get_user_print_options (&opts);
print_address_demangle (&opts, gdbarch, ptr_value, stream, demangle);
}
if (adjustment)
{
fprintf_filtered (stream, ", this adjustment ");
print_longest (stream, 'd', 1, adjustment);
}
}
