static struct type *
gnuv2_value_rtti_type (struct value *v, int *full, int *top, int *using_enc)
{
struct type *known_type;
struct type *rtti_type;
CORE_ADDR vtbl;
struct minimal_symbol *minsym;
char *demangled_name;
struct type *btype;
if (full)
*full = 0;
if (top)
*top = -1;
if (using_enc)
*using_enc = 0;
/* Get declared type */
known_type = value_type (v);
CHECK_TYPEDEF (known_type);
/* RTTI works only or class objects */
if (TYPE_CODE (known_type) != TYPE_CODE_CLASS)
return NULL;
/* Plan on this changing in the future as i get around to setting
the vtables properly for G++ compiled stuff. Also, I'll be using
the type info functions, which are always right. Deal with it
until then.
JCI - This pretty much useless. This gets the "true" type
correctly when there is single inheritance - but in all such
cases that I could find gdb already knows that. In cases
where this points INTO the object (like non-virtual diamond
graphs) the demangled name is something like OUTER::INNER
and this is not a symbol gdb can resolve, so we fail & return
NULL anyway. Seems like this really isn't going to work till
we actually call the RTTI function & parse it.
*/
/* If the type has no vptr fieldno, try to get it filled in */
if (TYPE_VPTR_FIELDNO(known_type) < 0)
fill_in_vptr_fieldno(known_type);
/* If we still can't find one, give up */
if (TYPE_VPTR_FIELDNO(known_type) < 0)
return NULL;
/* Make sure our basetype and known type match, otherwise, cast
so we can get at the vtable properly.
*/
btype = TYPE_VPTR_BASETYPE (known_type);
CHECK_TYPEDEF (btype);
if (btype != known_type )
{
v = value_cast (btype, v);
if (using_enc)
*using_enc=1;
}
/*
We can't use value_ind here, because it would want to use RTTI, and
we'd waste a bunch of time figuring out we already know the type.
Besides, we don't care about the type, just the actual pointer
*/
if (VALUE_ADDRESS (value_field (v, TYPE_VPTR_FIELDNO (known_type))) == 0)
return NULL;
vtbl=value_as_address(value_field(v,TYPE_VPTR_FIELDNO(known_type)));
/* Try to find a symbol that is the vtable */
minsym=lookup_minimal_symbol_by_pc(vtbl);
if (minsym==NULL
|| (demangled_name=DEPRECATED_SYMBOL_NAME (minsym))==NULL
|| !is_vtable_name (demangled_name))
return NULL;
/* If we just skip the prefix, we get screwed by namespaces */
demangled_name=cplus_demangle(demangled_name,DMGL_PARAMS|DMGL_ANSI);
*(strchr(demangled_name,' '))=0;
/* Lookup the type for the name */
/* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
rtti_type = cp_lookup_rtti_type (demangled_name, NULL);
if (rtti_type == NULL)
return NULL;
if (TYPE_N_BASECLASSES(rtti_type) > 1 && full && (*full) != 1)
{
if (top)
*top=TYPE_BASECLASS_BITPOS(rtti_type,TYPE_VPTR_FIELDNO(rtti_type))/8;
if (top && ((*top) >0))
{
if (TYPE_LENGTH(rtti_type) > TYPE_LENGTH(known_type))
{
if (full)
*full=0;
}
else
{
if (full)
*full=1;
}
}
}
else
{
if (full)
*full=1;
}
return rtti_type;
}
/* Return a virtual function as a value.
ARG1 is the object which provides the virtual function
table pointer. *ARG1P is side-effected in calling this function.
F is the list of member functions which contains the desired virtual
function.
J is an index into F which provides the desired virtual function.
TYPE is the type in which F is located. */
static struct value *
gnuv2_virtual_fn_field (struct value **arg1p, struct fn_field * f, int j,
struct type * type, int offset)
{
struct value *arg1 = *arg1p;
struct type *type1 = check_typedef (value_type (arg1));
struct type *entry_type;
/* First, get the virtual function table pointer. That comes
with a strange type, so cast it to type `pointer to long' (which
should serve just fine as a function type). Then, index into
the table, and convert final value to appropriate function type. */
struct value *entry;
struct value *vfn;
struct value *vtbl;
struct value *vi = value_from_longest (builtin_type_int,
(LONGEST) TYPE_FN_FIELD_VOFFSET (f, j));
struct type *fcontext = TYPE_FN_FIELD_FCONTEXT (f, j);
struct type *context;
if (fcontext == NULL)
/* We don't have an fcontext (e.g. the program was compiled with
g++ version 1). Try to get the vtbl from the TYPE_VPTR_BASETYPE.
This won't work right for multiple inheritance, but at least we
should do as well as GDB 3.x did. */
fcontext = TYPE_VPTR_BASETYPE (type);
context = lookup_pointer_type (fcontext);
/* Now context is a pointer to the basetype containing the vtbl. */
if (TYPE_TARGET_TYPE (context) != type1)
{
struct value *tmp = value_cast (context, value_addr (arg1));
arg1 = value_ind (tmp);
type1 = check_typedef (value_type (arg1));
}
context = type1;
/* Now context is the basetype containing the vtbl. */
/* This type may have been defined before its virtual function table
was. If so, fill in the virtual function table entry for the
type now. */
if (TYPE_VPTR_FIELDNO (context) < 0)
fill_in_vptr_fieldno (context);
/* The virtual function table is now an array of structures
which have the form { int16 offset, delta; void *pfn; }. */
vtbl = value_primitive_field (arg1, 0, TYPE_VPTR_FIELDNO (context),
TYPE_VPTR_BASETYPE (context));
/* With older versions of g++, the vtbl field pointed to an array
of structures. Nowadays it points directly to the structure. */
if (TYPE_CODE (value_type (vtbl)) == TYPE_CODE_PTR
&& TYPE_CODE (TYPE_TARGET_TYPE (value_type (vtbl))) == TYPE_CODE_ARRAY)
{
/* Handle the case where the vtbl field points to an
array of structures. */
vtbl = value_ind (vtbl);
/* Index into the virtual function table. This is hard-coded because
looking up a field is not cheap, and it may be important to save
time, e.g. if the user has set a conditional breakpoint calling
a virtual function. */
entry = value_subscript (vtbl, vi);
}
else
{
/* Handle the case where the vtbl field points directly to a structure. */
vtbl = value_add (vtbl, vi);
entry = value_ind (vtbl);
}
entry_type = check_typedef (value_type (entry));
if (TYPE_CODE (entry_type) == TYPE_CODE_STRUCT)
{
/* Move the `this' pointer according to the virtual function table. */
set_value_offset (arg1, value_offset (arg1) + value_as_long (value_field (entry, 0)));
if (!value_lazy (arg1))
{
set_value_lazy (arg1, 1);
value_fetch_lazy (arg1);
}
vfn = value_field (entry, 2);
}
else if (TYPE_CODE (entry_type) == TYPE_CODE_PTR)
vfn = entry;
else
error (_("I'm confused: virtual function table has bad type"));
/* Reinstantiate the function pointer with the correct type. */
deprecated_set_value_type (vfn, lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j)));
*arg1p = arg1;
return vfn;
}
static struct type *
gnuv2_value_rtti_type (struct value *v, int *full, int *top, int *using_enc)
{
struct type *known_type;
struct type *rtti_type;
CORE_ADDR vtbl;
struct bound_minimal_symbol minsym;
char *demangled_name, *p;
const char *linkage_name;
struct type *btype;
struct type *known_type_vptr_basetype;
int known_type_vptr_fieldno;
if (full)
*full = 0;
if (top)
*top = -1;
if (using_enc)
*using_enc = 0;
/* Get declared type. */
known_type = value_type (v);
CHECK_TYPEDEF (known_type);
/* RTTI works only or class objects. */
if (TYPE_CODE (known_type) != TYPE_CODE_STRUCT)
return NULL;
/* Plan on this changing in the future as i get around to setting
the vtables properly for G++ compiled stuff. Also, I'll be using
the type info functions, which are always right. Deal with it
until then. */
/* Try to get the vptr basetype, fieldno. */
known_type_vptr_fieldno = get_vptr_fieldno (known_type,
&known_type_vptr_basetype);
/* If we can't find it, give up. */
if (known_type_vptr_fieldno < 0)
return NULL;
/* Make sure our basetype and known type match, otherwise, cast
so we can get at the vtable properly. */
btype = known_type_vptr_basetype;
CHECK_TYPEDEF (btype);
if (btype != known_type )
{
v = value_cast (btype, v);
if (using_enc)
*using_enc=1;
}
/* We can't use value_ind here, because it would want to use RTTI, and
we'd waste a bunch of time figuring out we already know the type.
Besides, we don't care about the type, just the actual pointer. */
if (value_address (value_field (v, known_type_vptr_fieldno)) == 0)
return NULL;
vtbl = value_as_address (value_field (v, known_type_vptr_fieldno));
/* Try to find a symbol that is the vtable. */
minsym=lookup_minimal_symbol_by_pc(vtbl);
if (minsym.minsym==NULL
|| (linkage_name=MSYMBOL_LINKAGE_NAME (minsym.minsym))==NULL
|| !is_vtable_name (linkage_name))
return NULL;
/* If we just skip the prefix, we get screwed by namespaces. */
demangled_name=gdb_demangle(linkage_name,DMGL_PARAMS|DMGL_ANSI);
p = strchr (demangled_name, ' ');
if (p)
*p = '\0';
/* Lookup the type for the name. */
/* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
rtti_type = cp_lookup_rtti_type (demangled_name, NULL);
if (rtti_type == NULL)
return NULL;
if (TYPE_N_BASECLASSES(rtti_type) > 1 && full && (*full) != 1)
{
if (top)
*top = TYPE_BASECLASS_BITPOS (rtti_type,
TYPE_VPTR_FIELDNO(rtti_type)) / 8;
if (top && ((*top) >0))
{
if (TYPE_LENGTH(rtti_type) > TYPE_LENGTH(known_type))
{
if (full)
*full=0;
}
else
{
if (full)
*full=1;
}
}
}
else
{
if (full)
*full=1;
}
return rtti_type;
}
