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);
}
struct value *
value_subscript (struct value *array, LONGEST index)
{
int c_style = current_language->c_style_arrays;
struct type *tarray;
array = coerce_ref (array);
tarray = check_typedef (value_type (array));
if (TYPE_CODE (tarray) == TYPE_CODE_ARRAY
|| TYPE_CODE (tarray) == TYPE_CODE_STRING)
{
struct type *range_type = TYPE_INDEX_TYPE (tarray);
LONGEST lowerbound, upperbound;
get_discrete_bounds (range_type, &lowerbound, &upperbound);
if (VALUE_LVAL (array) != lval_memory)
return value_subscripted_rvalue (array, index, lowerbound);
if (c_style == 0)
{
if (index >= lowerbound && index <= upperbound)
return value_subscripted_rvalue (array, index, lowerbound);
/* Emit warning unless we have an array of unknown size.
An array of unknown size has lowerbound 0 and upperbound -1. */
if (upperbound > -1)
warning (_("array or string index out of range"));
/* fall doing C stuff */
c_style = 1;
}
index -= lowerbound;
array = value_coerce_array (array);
}
if (c_style)
return value_ind (value_ptradd (array, index));
else
error (_("not an array or string"));
}
static struct value *
evaluate_subexp_modula2 (struct type *expect_type, struct expression *exp,
int *pos, enum noside noside)
{
enum exp_opcode op = exp->elts[*pos].opcode;
struct value *arg1;
struct value *arg2;
struct type *type;
switch (op)
{
case UNOP_HIGH:
(*pos)++;
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
return arg1;
else
{
arg1 = coerce_ref (arg1);
type = check_typedef (value_type (arg1));
if (m2_is_unbounded_array (type))
{
struct value *temp = arg1;
type = TYPE_FIELD_TYPE (type, 1);
/* i18n: Do not translate the "_m2_high" part! */
arg1 = value_struct_elt (&temp, NULL, "_m2_high", NULL,
_("unbounded structure "
"missing _m2_high field"));
if (value_type (arg1) != type)
arg1 = value_cast (type, arg1);
}
}
return arg1;
case BINOP_SUBSCRIPT:
(*pos)++;
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
if (noside == EVAL_SKIP)
goto nosideret;
/* If the user attempts to subscript something that is not an
array or pointer type (like a plain int variable for example),
then report this as an error. */
arg1 = coerce_ref (arg1);
type = check_typedef (value_type (arg1));
if (m2_is_unbounded_array (type))
{
struct value *temp = arg1;
type = TYPE_FIELD_TYPE (type, 0);
if (type == NULL || (TYPE_CODE (type) != TYPE_CODE_PTR))
{
warning (_("internal error: unbounded "
"array structure is unknown"));
return evaluate_subexp_standard (expect_type, exp, pos, noside);
}
/* i18n: Do not translate the "_m2_contents" part! */
arg1 = value_struct_elt (&temp, NULL, "_m2_contents", NULL,
_("unbounded structure "
"missing _m2_contents field"));
if (value_type (arg1) != type)
arg1 = value_cast (type, arg1);
check_typedef (value_type (arg1));
return value_ind (value_ptradd (arg1, value_as_long (arg2)));
}
else
if (TYPE_CODE (type) != TYPE_CODE_ARRAY)
{
if (TYPE_NAME (type))
error (_("cannot subscript something of type `%s'"),
TYPE_NAME (type));
else
error (_("cannot subscript requested type"));
}
if (noside == EVAL_AVOID_SIDE_EFFECTS)
return value_zero (TYPE_TARGET_TYPE (type), VALUE_LVAL (arg1));
else
return value_subscript (arg1, value_as_long (arg2));
default:
return evaluate_subexp_standard (expect_type, exp, pos, noside);
}
nosideret:
return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
}
/* 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;
LONGEST vi = (LONGEST) TYPE_FN_FIELD_VOFFSET (f, j);
struct type *fcontext = TYPE_FN_FIELD_FCONTEXT (f, j);
struct type *context;
struct type *context_vptr_basetype;
int context_vptr_fieldno;
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. */
context_vptr_fieldno = get_vptr_fieldno (context, &context_vptr_basetype);
/* FIXME: What to do if vptr_fieldno is still -1? */
/* 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, context_vptr_fieldno,
context_vptr_basetype);
/* 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_ptradd (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;
}
