/* Abstraction of GNU v3 abi.
Contributed by Jim Blandy <jimb@redhat.com>
- Copyright (C) 2001, 2002, 2003, 2005, 2006, 2007, 2008
+ Copyright (C) 2001, 2002, 2003, 2005, 2006, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
This file is part of GDB.
#include "demangle.h"
#include "objfiles.h"
#include "valprint.h"
+#include "c-lang.h"
#include "gdb_assert.h"
#include "gdb_string.h"
}
-/* Determine architecture of class DOMAIN. This architecture is used
- to query C++ ABI details (types, method pointer layout, etc.).
-
- Note that we assume DOMAIN must have been allocated with an OBJFILE;
- GDB does not provide any built-in class types. Thus we use the
- architecture of that OBJFILE to define the C++ ABI. */
-
-static struct gdbarch *
-get_class_arch (struct type *domain)
-{
- gdb_assert (TYPE_CODE (domain) == TYPE_CODE_CLASS);
- gdb_assert (TYPE_OBJFILE (domain) != NULL);
- return get_objfile_arch (TYPE_OBJFILE (domain));
-}
-
/* To help us find the components of a vtable, we build ourselves a
GDB type object representing the vtable structure. Following the
V3 ABI, it goes something like this:
/* ARCH can't give us the true ptrdiff_t type, so we guess. */
struct type *ptrdiff_type
- = init_type (TYPE_CODE_INT,
- gdbarch_ptr_bit (arch) / TARGET_CHAR_BIT, 0,
- "ptrdiff_t", 0);
+ = arch_integer_type (arch, gdbarch_ptr_bit (arch), 0, "ptrdiff_t");
/* We assume no padding is necessary, since GDB doesn't know
anything about alignment at the moment. If this assumption bites
/* ptrdiff_t vcall_and_vbase_offsets[0]; */
FIELD_NAME (*field) = "vcall_and_vbase_offsets";
- FIELD_TYPE (*field)
- = create_array_type (0, ptrdiff_type,
- create_range_type (0, builtin_type_int32, 0, -1));
+ FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1);
FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
offset += TYPE_LENGTH (FIELD_TYPE (*field));
field++;
/* void (*virtual_functions[0]) (); */
FIELD_NAME (*field) = "virtual_functions";
- FIELD_TYPE (*field)
- = create_array_type (0, ptr_to_void_fn_type,
- create_range_type (0, builtin_type_int32, 0, -1));
+ FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1);
FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
offset += TYPE_LENGTH (FIELD_TYPE (*field));
field++;
/* We assumed in the allocation above that there were four fields. */
gdb_assert (field == (field_list + 4));
- t = init_type (TYPE_CODE_STRUCT, offset, 0, 0, 0);
+ t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL);
TYPE_NFIELDS (t) = field - field_list;
TYPE_FIELDS (t) = field_list;
TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable";
+ INIT_CPLUS_SPECIFIC (t);
return t;
}
}
+/* Determine whether structure TYPE is a dynamic class. Cache the
+ result. */
+
+static int
+gnuv3_dynamic_class (struct type *type)
+{
+ int fieldnum, fieldelem;
+
+ if (TYPE_CPLUS_DYNAMIC (type))
+ return TYPE_CPLUS_DYNAMIC (type) == 1;
+
+ ALLOCATE_CPLUS_STRUCT_TYPE (type);
+
+ for (fieldnum = 0; fieldnum < TYPE_N_BASECLASSES (type); fieldnum++)
+ if (BASETYPE_VIA_VIRTUAL (type, fieldnum)
+ || gnuv3_dynamic_class (TYPE_FIELD_TYPE (type, fieldnum)))
+ {
+ TYPE_CPLUS_DYNAMIC (type) = 1;
+ return 1;
+ }
+
+ for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
+ for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
+ fieldelem++)
+ {
+ struct fn_field *f = TYPE_FN_FIELDLIST1 (type, fieldnum);
+
+ if (TYPE_FN_FIELD_VIRTUAL_P (f, fieldelem))
+ {
+ TYPE_CPLUS_DYNAMIC (type) = 1;
+ return 1;
+ }
+ }
+
+ TYPE_CPLUS_DYNAMIC (type) = -1;
+ return 0;
+}
+
+/* Find the vtable for a value of CONTAINER_TYPE located at
+ CONTAINER_ADDR. Return a value of the correct vtable type for this
+ architecture, or NULL if CONTAINER does not have a vtable. */
+
+static struct value *
+gnuv3_get_vtable (struct gdbarch *gdbarch,
+ struct type *container_type, CORE_ADDR container_addr)
+{
+ struct type *vtable_type = gdbarch_data (gdbarch,
+ vtable_type_gdbarch_data);
+ struct type *vtable_pointer_type;
+ struct value *vtable_pointer;
+ CORE_ADDR vtable_address;
+
+ /* If this type does not have a virtual table, don't read the first
+ field. */
+ if (!gnuv3_dynamic_class (check_typedef (container_type)))
+ return NULL;
+
+ /* We do not consult the debug information to find the virtual table.
+ The ABI specifies that it is always at offset zero in any class,
+ and debug information may not represent it.
+
+ We avoid using value_contents on principle, because the object might
+ be large. */
+
+ /* Find the type "pointer to virtual table". */
+ vtable_pointer_type = lookup_pointer_type (vtable_type);
+
+ /* Load it from the start of the class. */
+ vtable_pointer = value_at (vtable_pointer_type, container_addr);
+ vtable_address = value_as_address (vtable_pointer);
+
+ /* Correct it to point at the start of the virtual table, rather
+ than the address point. */
+ return value_at_lazy (vtable_type,
+ vtable_address - vtable_address_point_offset (gdbarch));
+}
+
+
static struct type *
gnuv3_rtti_type (struct value *value,
int *full_p, int *top_p, int *using_enc_p)
{
struct gdbarch *gdbarch;
- struct type *vtable_type;
struct type *values_type = check_typedef (value_type (value));
- CORE_ADDR vtable_address;
struct value *vtable;
struct minimal_symbol *vtable_symbol;
const char *vtable_symbol_name;
const char *class_name;
struct type *run_time_type;
- struct type *base_type;
LONGEST offset_to_top;
- struct type *values_type_vptr_basetype;
- int values_type_vptr_fieldno;
/* We only have RTTI for class objects. */
if (TYPE_CODE (values_type) != TYPE_CODE_CLASS)
return NULL;
- /* This routine may be called for Java types that do not have
- a proper objfile. Just return NULL for those. */
- if (!TYPE_OBJFILE (values_type)
- || !TYPE_OBJFILE (values_type)->obfd)
- return NULL;
-
/* Determine architecture. */
- gdbarch = get_class_arch (values_type);
- vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
-
- /* If we can't find the virtual table pointer for values_type, we
- can't find the RTTI. */
- values_type_vptr_fieldno = get_vptr_fieldno (values_type,
- &values_type_vptr_basetype);
- if (values_type_vptr_fieldno == -1)
- return NULL;
+ gdbarch = get_type_arch (values_type);
if (using_enc_p)
*using_enc_p = 0;
- /* Fetch VALUE's virtual table pointer, and tweak it to point at
- an instance of our imaginary gdb_gnu_v3_abi_vtable structure. */
- base_type = check_typedef (values_type_vptr_basetype);
- if (values_type != base_type)
- {
- value = value_cast (base_type, value);
- if (using_enc_p)
- *using_enc_p = 1;
- }
- vtable_address
- = value_as_address (value_field (value, values_type_vptr_fieldno));
- vtable
- = value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (gdbarch));
-
+ vtable = gnuv3_get_vtable (gdbarch, value_type (value),
+ value_as_address (value_addr (value)));
+ if (vtable == NULL)
+ return NULL;
+
/* Find the linker symbol for this vtable. */
vtable_symbol
- = lookup_minimal_symbol_by_pc (VALUE_ADDRESS (vtable)
- + value_offset (vtable)
+ = lookup_minimal_symbol_by_pc (value_address (vtable)
+ value_embedded_offset (vtable));
if (! vtable_symbol)
return NULL;
>= TYPE_LENGTH (run_time_type)));
if (top_p)
*top_p = - offset_to_top;
-
return run_time_type;
}
-/* Find the vtable for CONTAINER and return a value of the correct
- vtable type for this architecture. */
-
-static struct value *
-gnuv3_get_vtable (struct gdbarch *gdbarch, struct value *container)
-{
- struct type *vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
- struct type *vtable_pointer_type;
- struct value *vtable_pointer;
- CORE_ADDR vtable_pointer_address, vtable_address;
-
- /* We do not consult the debug information to find the virtual table.
- The ABI specifies that it is always at offset zero in any class,
- and debug information may not represent it. We won't issue an
- error if there's a class with virtual functions but no virtual table
- pointer, but something's already gone seriously wrong if that
- happens.
-
- We avoid using value_contents on principle, because the object might
- be large. */
-
- /* Find the type "pointer to virtual table". */
- vtable_pointer_type = lookup_pointer_type (vtable_type);
-
- /* Load it from the start of the class. */
- vtable_pointer_address = value_as_address (value_addr (container));
- vtable_pointer = value_at (vtable_pointer_type, vtable_pointer_address);
- vtable_address = value_as_address (vtable_pointer);
-
- /* Correct it to point at the start of the virtual table, rather
- than the address point. */
- return value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (gdbarch));
-}
-
/* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
function, of type FNTYPE. */
gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container,
struct type *fntype, int vtable_index)
{
- struct value *vtable = gnuv3_get_vtable (gdbarch, container);
- struct value *vfn;
+ struct value *vtable, *vfn;
+
+ /* Every class with virtual functions must have a vtable. */
+ vtable = gnuv3_get_vtable (gdbarch, value_type (container),
+ value_as_address (value_addr (container)));
+ gdb_assert (vtable != NULL);
/* Fetch the appropriate function pointer from the vtable. */
vfn = value_subscript (value_field (vtable, vtable_field_virtual_functions),
- value_from_longest (builtin_type_int32, vtable_index));
+ vtable_index);
/* If this architecture uses function descriptors directly in the vtable,
then the address of the vtable entry is actually a "function pointer"
error (_("Only classes can have virtual functions."));
/* Determine architecture. */
- gdbarch = get_class_arch (values_type);
+ gdbarch = get_type_arch (values_type);
/* Cast our value to the base class which defines this virtual
function. This takes care of any necessary `this'
CORE_ADDR address)
{
struct gdbarch *gdbarch;
- struct type *vtable_type;
struct type *ptr_type;
struct value *vtable;
- struct type *vbasetype;
- struct value *offset_val, *vbase_array;
- CORE_ADDR vtable_address;
+ struct value *vbase_array;
long int cur_base_offset, base_offset;
- int vbasetype_vptr_fieldno;
/* Determine architecture. */
- gdbarch = get_class_arch (type);
- vtable_type = gdbarch_data (gdbarch, vtable_type_gdbarch_data);
+ gdbarch = get_type_arch (type);
ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
/* If it isn't a virtual base, this is easy. The offset is in the
error (_("Misaligned vbase offset."));
cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type));
- /* 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);
- vbasetype_vptr_fieldno = get_vptr_fieldno (vbasetype, NULL);
-
- if (vbasetype_vptr_fieldno >= 0
- && TYPE_FIELD_BITPOS (vbasetype, vbasetype_vptr_fieldno) != 0)
- error (_("Illegal vptr offset in class %s"),
- TYPE_NAME (vbasetype) ? TYPE_NAME (vbasetype) : "<unknown>");
-
- vtable_address = value_as_address (value_at_lazy (ptr_type, address));
- vtable
- = value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (gdbarch));
- offset_val = value_from_longest (builtin_type_int32, cur_base_offset);
+ vtable = gnuv3_get_vtable (gdbarch, type, address);
+ gdb_assert (vtable != NULL);
vbase_array = value_field (vtable, vtable_field_vcall_and_vbase_offsets);
- base_offset = value_as_long (value_subscript (vbase_array, offset_val));
+ base_offset = value_as_long (value_subscript (vbase_array, cur_base_offset));
return base_offset;
}
which has virtual table index VOFFSET. The method has an associated
"this" adjustment of ADJUSTMENT bytes. */
-const char *
+static 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;
{
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;
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));
+ 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));
+ adjustment = extract_signed_integer (contents,
+ TYPE_LENGTH (offset_type), byte_order);
if (!gdbarch_vbit_in_delta (gdbarch))
{
struct ui_file *stream)
{
struct type *domain = TYPE_DOMAIN_TYPE (type);
- struct gdbarch *gdbarch = get_class_arch (domain);
+ struct gdbarch *gdbarch = get_type_arch (domain);
CORE_ADDR ptr_value;
LONGEST adjustment;
int vbit;
{
char *demangled_name = cplus_demangle (physname,
DMGL_ANSI | DMGL_PARAMS);
- if (demangled_name != NULL)
+
+ fprintf_filtered (stream, "&virtual ");
+ if (demangled_name == NULL)
+ fputs_filtered (physname, stream);
+ else
{
- fprintf_filtered (stream, "&virtual ");
fputs_filtered (demangled_name, stream);
xfree (demangled_name);
- return;
}
+ 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);
+ fputs_filtered (") ", stream);
+ }
/* We didn't find it; print the raw data. */
if (vbit)
print_longest (stream, 'd', 1, ptr_value);
}
else
- print_address_demangle (ptr_value, stream, demangle);
+ print_address_demangle (gdbarch, ptr_value, stream, demangle);
if (adjustment)
{
gnuv3_method_ptr_size (struct type *type)
{
struct type *domain_type = check_typedef (TYPE_DOMAIN_TYPE (type));
- struct gdbarch *gdbarch = get_class_arch (domain_type);
+ struct gdbarch *gdbarch = get_type_arch (domain_type);
+
return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
}
CORE_ADDR value, int is_virtual)
{
struct type *domain_type = check_typedef (TYPE_DOMAIN_TYPE (type));
- struct gdbarch *gdbarch = get_class_arch (domain_type);
+ struct gdbarch *gdbarch = get_type_arch (domain_type);
int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
/* FIXME drow/2006-12-24: The adjustment of "this" is currently
always zero, since the method pointer is of the correct type.
if (!gdbarch_vbit_in_delta (gdbarch))
{
- store_unsigned_integer (contents, size, value | is_virtual);
- store_unsigned_integer (contents + size, size, 0);
+ store_unsigned_integer (contents, size, byte_order, value | is_virtual);
+ store_unsigned_integer (contents + size, size, byte_order, 0);
}
else
{
- store_unsigned_integer (contents, size, value);
- store_unsigned_integer (contents + size, size, is_virtual);
+ store_unsigned_integer (contents, size, byte_order, value);
+ store_unsigned_integer (contents + size, size, byte_order, is_virtual);
}
}
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)));
method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
/* Extract the pointer to member. */
- gdbarch = get_class_arch (domain_type);
+ gdbarch = get_type_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
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_ptradd (*this_p, adjustment);
*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);