/* Abstraction of GNU v3 abi.
Contributed by Jim Blandy <jimb@redhat.com>
- Copyright 2001, 2002 Free Software Foundation, Inc.
+ Copyright (C) 2001-2020 Free Software Foundation, Inc.
This file is part of GDB.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "value.h"
#include "cp-abi.h"
+#include "cp-support.h"
#include "demangle.h"
-#include "gdb_assert.h"
-#include "gdb_string.h"
+#include "dwarf2.h"
+#include "objfiles.h"
+#include "valprint.h"
+#include "c-lang.h"
+#include "typeprint.h"
+#include <algorithm>
+#include "cli/cli-style.h"
static struct cp_abi_ops gnu_v3_abi_ops;
+/* A gdbarch key for std::type_info, in the event that it can't be
+ found in the debug info. */
+
+static struct gdbarch_data *std_type_info_gdbarch_data;
+
+
static int
gnuv3_is_vtable_name (const char *name)
{
- return strncmp (name, "_ZTV", 4) == 0;
+ return startswith (name, "_ZTV");
}
static int
gnuv3_is_operator_name (const char *name)
{
- return strncmp (name, "operator", 8) == 0;
+ return startswith (name, CP_OPERATOR_STR);
}
described above, laid out appropriately for ARCH.
We use this function as the gdbarch per-architecture data
- initialization function. We assume that the gdbarch framework
- calls the per-architecture data initialization functions after it
- sets current_gdbarch to the new architecture. */
+ initialization function. */
static void *
build_gdb_vtable_type (struct gdbarch *arch)
{
int offset;
struct type *void_ptr_type
- = lookup_pointer_type (builtin_type_void);
+ = builtin_type (arch)->builtin_data_ptr;
struct type *ptr_to_void_fn_type
- = lookup_pointer_type (lookup_function_type (builtin_type_void));
+ = builtin_type (arch)->builtin_func_ptr;
/* ARCH can't give us the true ptrdiff_t type, so we guess. */
struct type *ptrdiff_type
- = init_type (TYPE_CODE_INT, TARGET_PTR_BIT / 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
the alignment that type requires, and then use that here. */
/* Build the field list. */
- field_list = xmalloc (sizeof (struct field [4]));
- memset (field_list, 0, sizeof (struct field [4]));
+ field_list = XCNEWVEC (struct field, 4);
field = &field_list[0];
offset = 0;
/* 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_int, 0, -1));
- FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
+ FIELD_TYPE (*field) = lookup_array_range_type (ptrdiff_type, 0, -1);
+ SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
offset += TYPE_LENGTH (FIELD_TYPE (*field));
field++;
/* ptrdiff_t offset_to_top; */
FIELD_NAME (*field) = "offset_to_top";
FIELD_TYPE (*field) = ptrdiff_type;
- FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
+ SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
offset += TYPE_LENGTH (FIELD_TYPE (*field));
field++;
/* void *type_info; */
FIELD_NAME (*field) = "type_info";
FIELD_TYPE (*field) = void_ptr_type;
- FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
+ SET_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_int, 0, -1));
- FIELD_BITPOS (*field) = offset * TARGET_CHAR_BIT;
+ FIELD_TYPE (*field) = lookup_array_range_type (ptr_to_void_fn_type, 0, -1);
+ SET_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 * TARGET_CHAR_BIT, NULL);
TYPE_NFIELDS (t) = field - field_list;
TYPE_FIELDS (t) = field_list;
- TYPE_TAG_NAME (t) = "gdb_gnu_v3_abi_vtable";
+ TYPE_NAME (t) = "gdb_gnu_v3_abi_vtable";
+ INIT_CPLUS_SPECIFIC (t);
- return t;
+ return make_type_with_address_space (t, TYPE_INSTANCE_FLAG_CODE_SPACE);
}
+/* Return the ptrdiff_t type used in the vtable type. */
+static struct type *
+vtable_ptrdiff_type (struct gdbarch *gdbarch)
+{
+ struct type *vtable_type
+ = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data);
+
+ /* The "offset_to_top" field has the appropriate (ptrdiff_t) type. */
+ return TYPE_FIELD_TYPE (vtable_type, vtable_field_offset_to_top);
+}
+
/* Return the offset from the start of the imaginary `struct
gdb_gnu_v3_abi_vtable' object to the vtable's "address point"
(i.e., where objects' virtual table pointers point). */
static int
-vtable_address_point_offset (void)
+vtable_address_point_offset (struct gdbarch *gdbarch)
{
- struct type *vtable_type = gdbarch_data (current_gdbarch,
- vtable_type_gdbarch_data);
+ struct type *vtable_type
+ = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data);
return (TYPE_FIELD_BITPOS (vtable_type, vtable_field_virtual_functions)
/ TARGET_CHAR_BIT);
}
+/* Determine whether structure TYPE is a dynamic class. Cache the
+ result. */
+
+static int
+gnuv3_dynamic_class (struct type *type)
+{
+ int fieldnum, fieldelem;
+
+ type = check_typedef (type);
+ gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT
+ || TYPE_CODE (type) == TYPE_CODE_UNION);
+
+ if (TYPE_CODE (type) == TYPE_CODE_UNION)
+ return 0;
+
+ 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
+ = (struct type *) gdbarch_data (gdbarch, vtable_type_gdbarch_data);
+ struct type *vtable_pointer_type;
+ struct value *vtable_pointer;
+ CORE_ADDR vtable_address;
+
+ container_type = check_typedef (container_type);
+ gdb_assert (TYPE_CODE (container_type) == TYPE_CODE_STRUCT);
+
+ /* If this type does not have a virtual table, don't read the first
+ field. */
+ if (!gnuv3_dynamic_class (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)
+ int *full_p, LONGEST *top_p, int *using_enc_p)
{
- struct type *vtable_type = gdbarch_data (current_gdbarch,
- vtable_type_gdbarch_data);
- struct type *value_type = check_typedef (VALUE_TYPE (value));
- CORE_ADDR vtable_address;
+ struct gdbarch *gdbarch;
+ struct type *values_type = check_typedef (value_type (value));
struct value *vtable;
struct minimal_symbol *vtable_symbol;
const char *vtable_symbol_name;
const char *class_name;
- struct symbol *class_symbol;
struct type *run_time_type;
- struct type *base_type;
LONGEST offset_to_top;
+ const char *atsign;
- /* We only have RTTI for class objects. */
- if (TYPE_CODE (value_type) != TYPE_CODE_CLASS)
+ /* We only have RTTI for dynamic class objects. */
+ if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT
+ || !gnuv3_dynamic_class (values_type))
return NULL;
- /* If we can't find the virtual table pointer for value_type, we
- can't find the RTTI. */
- fill_in_vptr_fieldno (value_type);
- if (TYPE_VPTR_FIELDNO (value_type) == -1)
- return NULL;
+ /* Determine architecture. */
+ 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 (TYPE_VPTR_BASETYPE (value_type));
- if (value_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, TYPE_VPTR_FIELDNO (value_type)));
- vtable = value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (),
- VALUE_BFD_SECTION (value));
-
+ vtable = gnuv3_get_vtable (gdbarch, values_type,
+ 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)
- + VALUE_EMBEDDED_OFFSET (vtable));
+ = lookup_minimal_symbol_by_pc (value_address (vtable)
+ + value_embedded_offset (vtable)).minsym;
if (! vtable_symbol)
return NULL;
If we didn't like this approach, we could instead look in the
type_info object itself to get the class name. But this way
should work just as well, and doesn't read target memory. */
- vtable_symbol_name = SYMBOL_DEMANGLED_NAME (vtable_symbol);
+ vtable_symbol_name = vtable_symbol->demangled_name ();
if (vtable_symbol_name == NULL
- || strncmp (vtable_symbol_name, "vtable for ", 11))
+ || !startswith (vtable_symbol_name, "vtable for "))
{
- warning ("can't find linker symbol for virtual table for `%s' value",
- TYPE_NAME (value_type));
+ warning (_("can't find linker symbol for virtual table for `%s' value"),
+ TYPE_SAFE_NAME (values_type));
if (vtable_symbol_name)
- warning (" found `%s' instead", vtable_symbol_name);
+ warning (_(" found `%s' instead"), vtable_symbol_name);
return NULL;
}
class_name = vtable_symbol_name + 11;
- /* Try to look up the class name as a type name. */
- class_symbol = lookup_symbol (class_name, 0, STRUCT_NAMESPACE, 0, 0);
- if (! class_symbol)
+ /* Strip off @plt and version suffixes. */
+ atsign = strchr (class_name, '@');
+ if (atsign != NULL)
{
- warning ("can't find class named `%s', as given by C++ RTTI", class_name);
- return NULL;
- }
+ char *copy;
- /* Make sure the type symbol is sane. (An earlier version of this
- code would find constructor functions, who have the same name as
- the class.) */
- if (SYMBOL_CLASS (class_symbol) != LOC_TYPEDEF
- || TYPE_CODE (SYMBOL_TYPE (class_symbol)) != TYPE_CODE_CLASS)
- {
- warning ("C++ RTTI gives a class name of `%s', but that isn't a type name",
- class_name);
- return NULL;
+ copy = (char *) alloca (atsign - class_name + 1);
+ memcpy (copy, class_name, atsign - class_name);
+ copy[atsign - class_name] = '\0';
+ class_name = copy;
}
- /* This is the object's run-time type! */
- run_time_type = SYMBOL_TYPE (class_symbol);
+ /* Try to look up the class name as a type name. */
+ /* FIXME: chastain/2003-11-26: block=NULL is bogus. See pr gdb/1465. */
+ run_time_type = cp_lookup_rtti_type (class_name, NULL);
+ if (run_time_type == NULL)
+ return NULL;
/* Get the offset from VALUE to the top of the complete object.
NOTE: this is the reverse of the meaning of *TOP_P. */
= value_as_long (value_field (vtable, vtable_field_offset_to_top));
if (full_p)
- *full_p = (- offset_to_top == VALUE_EMBEDDED_OFFSET (value)
- && (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (value))
+ *full_p = (- offset_to_top == value_embedded_offset (value)
+ && (TYPE_LENGTH (value_enclosing_type (value))
>= TYPE_LENGTH (run_time_type)));
if (top_p)
*top_p = - offset_to_top;
-
return run_time_type;
}
+/* Return a function pointer for CONTAINER's VTABLE_INDEX'th virtual
+ function, of type FNTYPE. */
static struct value *
-gnuv3_virtual_fn_field (struct value **value_p,
- struct fn_field *f, int j,
- struct type *type, int offset)
+gnuv3_get_virtual_fn (struct gdbarch *gdbarch, struct value *container,
+ struct type *fntype, int vtable_index)
{
- struct type *vtable_type = gdbarch_data (current_gdbarch,
- vtable_type_gdbarch_data);
- struct value *value = *value_p;
- struct type *value_type = check_typedef (VALUE_TYPE (value));
- struct type *vfn_base;
- CORE_ADDR vtable_address;
- struct value *vtable;
- struct value *vfn;
+ struct value *vtable, *vfn;
- /* Some simple sanity checks. */
- if (TYPE_CODE (value_type) != TYPE_CODE_CLASS)
- error ("Only classes can have virtual functions.");
-
- /* Find the base class that defines this virtual function. */
- vfn_base = TYPE_FN_FIELD_FCONTEXT (f, j);
- if (! vfn_base)
- /* In programs compiled with G++ version 1, the debug info doesn't
- say which base class defined the virtual function. We'll guess
- it's the same base class that has our vtable; this is wrong for
- multiple inheritance, but it's better than nothing. */
- vfn_base = TYPE_VPTR_BASETYPE (type);
-
- /* 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 (vfn_base) < 0)
- fill_in_vptr_fieldno (vfn_base);
- if (TYPE_VPTR_FIELDNO (vfn_base) < 0)
- error ("Could not find virtual table pointer for class \"%s\".",
- TYPE_TAG_NAME (vfn_base) ? TYPE_TAG_NAME (vfn_base) : "<unknown>");
-
- /* Now that we know which base class is defining our virtual
- function, cast our value to that baseclass. This takes care of
- any necessary `this' adjustments. */
- if (vfn_base != value_type)
- value = value_cast (vfn_base, value);
-
- /* Now value is an object of the appropriate base type. Fetch its
- virtual table. */
- /* It might be possible to do this cast at the same time as the above.
- Does multiple inheritance affect this?
- Can this even trigger, or is TYPE_VPTR_BASETYPE idempotent?
- */
- if (TYPE_VPTR_BASETYPE (vfn_base) != vfn_base)
- value = value_cast (TYPE_VPTR_BASETYPE (vfn_base), value);
- vtable_address
- = value_as_address (value_field (value, TYPE_VPTR_FIELDNO (vfn_base)));
-
- vtable = value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (),
- VALUE_BFD_SECTION (value));
+ /* 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_int,
- TYPE_FN_FIELD_VOFFSET (f, j)));
+ vtable_index);
- /* Cast the function pointer to the appropriate type. */
- vfn = value_cast (lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j)),
- vfn);
+ /* If this architecture uses function descriptors directly in the vtable,
+ then the address of the vtable entry is actually a "function pointer"
+ (i.e. points to the descriptor). We don't need to scale the index
+ by the size of a function descriptor; GCC does that before outputting
+ debug information. */
+ if (gdbarch_vtable_function_descriptors (gdbarch))
+ vfn = value_addr (vfn);
- /* Is (type)value always numerically the same as (vfn_base)value?
- If so we can spare this cast and use one of the ones above. */
- *value_p = value_addr (value_cast (type, *value_p));
+ /* Cast the function pointer to the appropriate type. */
+ vfn = value_cast (lookup_pointer_type (fntype), vfn);
return vfn;
}
+/* 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));
+ struct gdbarch *gdbarch;
+
+ /* Some simple sanity checks. */
+ if (TYPE_CODE (values_type) != TYPE_CODE_STRUCT)
+ error (_("Only classes can have virtual functions."));
+
+ /* Determine architecture. */
+ 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'
+ adjustments. */
+ if (vfn_base != values_type)
+ *value_p = value_cast (vfn_base, *value_p);
+
+ return gnuv3_get_virtual_fn (gdbarch, *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. */
-int
-gnuv3_baseclass_offset (struct type *type, int index, char *valaddr,
- CORE_ADDR address)
+ -1 is returned on error. */
+
+static int
+gnuv3_baseclass_offset (struct type *type, int index,
+ const bfd_byte *valaddr, LONGEST embedded_offset,
+ CORE_ADDR address, const struct value *val)
{
- struct type *vtable_type = gdbarch_data (current_gdbarch,
- vtable_type_gdbarch_data);
+ struct gdbarch *gdbarch;
+ 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;
+ /* Determine architecture. */
+ 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
type definition. */
if (!BASETYPE_VIA_VIRTUAL (type, index))
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. */
-
- vbasetype = TYPE_VPTR_BASETYPE (type);
- if (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, NULL));
- vtable = value_at_lazy (vtable_type,
- vtable_address - vtable_address_point_offset (),
- NULL);
- offset_val = value_from_longest(builtin_type_int, cur_base_offset);
+ if (cur_base_offset >= - vtable_address_point_offset (gdbarch))
+ error (_("Expected a negative vbase offset (old compiler?)"));
+
+ cur_base_offset = cur_base_offset + vtable_address_point_offset (gdbarch);
+ if ((- cur_base_offset) % TYPE_LENGTH (ptr_type) != 0)
+ error (_("Misaligned vbase offset."));
+ cur_base_offset = cur_base_offset / ((int) TYPE_LENGTH (ptr_type));
+
+ vtable = gnuv3_get_vtable (gdbarch, type, address + embedded_offset);
+ 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;
}
+/* 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. */
+
+static const char *
+gnuv3_find_method_in (struct type *domain, CORE_ADDR voffset,
+ LONGEST adjustment)
+{
+ int i;
+
+ /* Search this class first. */
+ 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;
+}
+
+/* Decode GNU v3 method pointer. */
+
+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;
+}
+
+/* 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)
+{
+ struct type *self_type = TYPE_SELF_TYPE (type);
+ struct gdbarch *gdbarch = get_type_arch (self_type);
+ 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 (self_type, 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);
+ }
+}
+
+/* GNU v3 implementation of cplus_method_ptr_size. */
+
+static int
+gnuv3_method_ptr_size (struct type *type)
+{
+ struct gdbarch *gdbarch = get_type_arch (type);
+
+ return 2 * TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
+}
+
+/* GNU v3 implementation of cplus_make_method_ptr. */
+
+static void
+gnuv3_make_method_ptr (struct type *type, gdb_byte *contents,
+ CORE_ADDR value, int is_virtual)
+{
+ struct gdbarch *gdbarch = get_type_arch (type);
+ int size = TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr);
+ enum bfd_endian byte_order = type_byte_order (type);
+
+ /* 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 (gdbarch))
+ {
+ 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, byte_order, value);
+ store_unsigned_integer (contents + size, size, byte_order, 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)
+{
+ struct gdbarch *gdbarch;
+ const gdb_byte *contents = value_contents (method_ptr);
+ CORE_ADDR ptr_value;
+ struct type *self_type, *final_type, *method_type;
+ LONGEST adjustment;
+ int vbit;
+
+ self_type = TYPE_SELF_TYPE (check_typedef (value_type (method_ptr)));
+ final_type = lookup_pointer_type (self_type);
+
+ method_type = TYPE_TARGET_TYPE (check_typedef (value_type (method_ptr)));
+
+ /* Extract the pointer to member. */
+ gdbarch = get_type_arch (self_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);
+ *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);
+ }
+ else
+ return value_from_pointer (lookup_pointer_type (method_type), ptr_value);
+}
+
+/* Objects of this type are stored in a hash table and a vector when
+ printing the vtables for a class. */
+
+struct value_and_voffset
+{
+ /* The value representing the object. */
+ struct value *value;
+
+ /* The maximum vtable offset we've found for any object at this
+ offset in the outermost object. */
+ int max_voffset;
+};
+
+/* Hash function for value_and_voffset. */
+
+static hashval_t
+hash_value_and_voffset (const void *p)
+{
+ const struct value_and_voffset *o = (const struct value_and_voffset *) p;
+
+ return value_address (o->value) + value_embedded_offset (o->value);
+}
+
+/* Equality function for value_and_voffset. */
+
+static int
+eq_value_and_voffset (const void *a, const void *b)
+{
+ const struct value_and_voffset *ova = (const struct value_and_voffset *) a;
+ const struct value_and_voffset *ovb = (const struct value_and_voffset *) b;
+
+ return (value_address (ova->value) + value_embedded_offset (ova->value)
+ == value_address (ovb->value) + value_embedded_offset (ovb->value));
+}
+
+/* Comparison function for value_and_voffset. */
+
+static bool
+compare_value_and_voffset (const struct value_and_voffset *va,
+ const struct value_and_voffset *vb)
+{
+ CORE_ADDR addra = (value_address (va->value)
+ + value_embedded_offset (va->value));
+ CORE_ADDR addrb = (value_address (vb->value)
+ + value_embedded_offset (vb->value));
+
+ return addra < addrb;
+}
+
+/* A helper function used when printing vtables. This determines the
+ key (most derived) sub-object at each address and also computes the
+ maximum vtable offset seen for the corresponding vtable. Updates
+ OFFSET_HASH and OFFSET_VEC with a new value_and_voffset object, if
+ needed. VALUE is the object to examine. */
+
+static void
+compute_vtable_size (htab_t offset_hash,
+ std::vector<value_and_voffset *> *offset_vec,
+ struct value *value)
+{
+ int i;
+ struct type *type = check_typedef (value_type (value));
+ void **slot;
+ struct value_and_voffset search_vo, *current_vo;
+
+ gdb_assert (TYPE_CODE (type) == TYPE_CODE_STRUCT);
+
+ /* If the object is not dynamic, then we are done; as it cannot have
+ dynamic base types either. */
+ if (!gnuv3_dynamic_class (type))
+ return;
+
+ /* Update the hash and the vec, if needed. */
+ search_vo.value = value;
+ slot = htab_find_slot (offset_hash, &search_vo, INSERT);
+ if (*slot)
+ current_vo = (struct value_and_voffset *) *slot;
+ else
+ {
+ current_vo = XNEW (struct value_and_voffset);
+ current_vo->value = value;
+ current_vo->max_voffset = -1;
+ *slot = current_vo;
+ offset_vec->push_back (current_vo);
+ }
+
+ /* Update the value_and_voffset object with the highest vtable
+ offset from this class. */
+ for (i = 0; i < TYPE_NFN_FIELDS (type); ++i)
+ {
+ int j;
+ struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, i);
+
+ for (j = 0; j < TYPE_FN_FIELDLIST_LENGTH (type, i); ++j)
+ {
+ if (TYPE_FN_FIELD_VIRTUAL_P (fn, j))
+ {
+ int voffset = TYPE_FN_FIELD_VOFFSET (fn, j);
+
+ if (voffset > current_vo->max_voffset)
+ current_vo->max_voffset = voffset;
+ }
+ }
+ }
+
+ /* Recurse into base classes. */
+ for (i = 0; i < TYPE_N_BASECLASSES (type); ++i)
+ compute_vtable_size (offset_hash, offset_vec, value_field (value, i));
+}
+
+/* Helper for gnuv3_print_vtable that prints a single vtable. */
+
+static void
+print_one_vtable (struct gdbarch *gdbarch, struct value *value,
+ int max_voffset,
+ struct value_print_options *opts)
+{
+ int i;
+ struct type *type = check_typedef (value_type (value));
+ struct value *vtable;
+ CORE_ADDR vt_addr;
+
+ vtable = gnuv3_get_vtable (gdbarch, type,
+ value_address (value)
+ + value_embedded_offset (value));
+ vt_addr = value_address (value_field (vtable,
+ vtable_field_virtual_functions));
+
+ printf_filtered (_("vtable for '%s' @ %s (subobject @ %s):\n"),
+ TYPE_SAFE_NAME (type),
+ paddress (gdbarch, vt_addr),
+ paddress (gdbarch, (value_address (value)
+ + value_embedded_offset (value))));
+
+ for (i = 0; i <= max_voffset; ++i)
+ {
+ /* Initialize it just to avoid a GCC false warning. */
+ CORE_ADDR addr = 0;
+ int got_error = 0;
+ struct value *vfn;
+
+ printf_filtered ("[%d]: ", i);
+
+ vfn = value_subscript (value_field (vtable,
+ vtable_field_virtual_functions),
+ i);
+
+ if (gdbarch_vtable_function_descriptors (gdbarch))
+ vfn = value_addr (vfn);
+
+ try
+ {
+ addr = value_as_address (vfn);
+ }
+ catch (const gdb_exception_error &ex)
+ {
+ fprintf_styled (gdb_stdout, metadata_style.style (),
+ _("<error: %s>"), ex.what ());
+ got_error = 1;
+ }
+
+ if (!got_error)
+ print_function_pointer_address (opts, gdbarch, addr, gdb_stdout);
+ printf_filtered ("\n");
+ }
+}
+
+/* Implementation of the print_vtable method. */
+
+static void
+gnuv3_print_vtable (struct value *value)
+{
+ struct gdbarch *gdbarch;
+ struct type *type;
+ struct value *vtable;
+ struct value_print_options opts;
+ int count;
+
+ value = coerce_ref (value);
+ type = check_typedef (value_type (value));
+ if (TYPE_CODE (type) == TYPE_CODE_PTR)
+ {
+ value = value_ind (value);
+ type = check_typedef (value_type (value));
+ }
+
+ get_user_print_options (&opts);
+
+ /* Respect 'set print object'. */
+ if (opts.objectprint)
+ {
+ value = value_full_object (value, NULL, 0, 0, 0);
+ type = check_typedef (value_type (value));
+ }
+
+ gdbarch = get_type_arch (type);
+
+ vtable = NULL;
+ if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
+ vtable = gnuv3_get_vtable (gdbarch, type,
+ value_as_address (value_addr (value)));
+
+ if (!vtable)
+ {
+ printf_filtered (_("This object does not have a virtual function table\n"));
+ return;
+ }
+
+ htab_up offset_hash (htab_create_alloc (1, hash_value_and_voffset,
+ eq_value_and_voffset,
+ xfree, xcalloc, xfree));
+ std::vector<value_and_voffset *> result_vec;
+
+ compute_vtable_size (offset_hash.get (), &result_vec, value);
+ std::sort (result_vec.begin (), result_vec.end (),
+ compare_value_and_voffset);
+
+ count = 0;
+ for (value_and_voffset *iter : result_vec)
+ {
+ if (iter->max_voffset >= 0)
+ {
+ if (count > 0)
+ printf_filtered ("\n");
+ print_one_vtable (gdbarch, iter->value, iter->max_voffset, &opts);
+ ++count;
+ }
+ }
+}
+
+/* Return a GDB type representing `struct std::type_info', laid out
+ appropriately for ARCH.
+
+ We use this function as the gdbarch per-architecture data
+ initialization function. */
+
+static void *
+build_std_type_info_type (struct gdbarch *arch)
+{
+ struct type *t;
+ struct field *field_list, *field;
+ int offset;
+ struct type *void_ptr_type
+ = builtin_type (arch)->builtin_data_ptr;
+ struct type *char_type
+ = builtin_type (arch)->builtin_char;
+ struct type *char_ptr_type
+ = make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL);
+
+ field_list = XCNEWVEC (struct field, 2);
+ field = &field_list[0];
+ offset = 0;
+
+ /* The vtable. */
+ FIELD_NAME (*field) = "_vptr.type_info";
+ FIELD_TYPE (*field) = void_ptr_type;
+ SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
+ offset += TYPE_LENGTH (FIELD_TYPE (*field));
+ field++;
+
+ /* The name. */
+ FIELD_NAME (*field) = "__name";
+ FIELD_TYPE (*field) = char_ptr_type;
+ SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT);
+ offset += TYPE_LENGTH (FIELD_TYPE (*field));
+ field++;
+
+ gdb_assert (field == (field_list + 2));
+
+ t = arch_type (arch, TYPE_CODE_STRUCT, offset * TARGET_CHAR_BIT, NULL);
+ TYPE_NFIELDS (t) = field - field_list;
+ TYPE_FIELDS (t) = field_list;
+ TYPE_NAME (t) = "gdb_gnu_v3_type_info";
+ INIT_CPLUS_SPECIFIC (t);
+
+ return t;
+}
+
+/* Implement the 'get_typeid_type' method. */
+
+static struct type *
+gnuv3_get_typeid_type (struct gdbarch *gdbarch)
+{
+ struct symbol *typeinfo;
+ struct type *typeinfo_type;
+
+ typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN,
+ NULL).symbol;
+ if (typeinfo == NULL)
+ typeinfo_type
+ = (struct type *) gdbarch_data (gdbarch, std_type_info_gdbarch_data);
+ else
+ typeinfo_type = SYMBOL_TYPE (typeinfo);
+
+ return typeinfo_type;
+}
+
+/* Implement the 'get_typeid' method. */
+
+static struct value *
+gnuv3_get_typeid (struct value *value)
+{
+ struct type *typeinfo_type;
+ struct type *type;
+ struct gdbarch *gdbarch;
+ struct value *result;
+ std::string type_name, canonical;
+
+ /* We have to handle values a bit trickily here, to allow this code
+ to work properly with non_lvalue values that are really just
+ disguised types. */
+ if (value_lval_const (value) == lval_memory)
+ value = coerce_ref (value);
+
+ type = check_typedef (value_type (value));
+
+ /* In the non_lvalue case, a reference might have slipped through
+ here. */
+ if (TYPE_CODE (type) == TYPE_CODE_REF)
+ type = check_typedef (TYPE_TARGET_TYPE (type));
+
+ /* Ignore top-level cv-qualifiers. */
+ type = make_cv_type (0, 0, type, NULL);
+ gdbarch = get_type_arch (type);
+
+ type_name = type_to_string (type);
+ if (type_name.empty ())
+ error (_("cannot find typeinfo for unnamed type"));
+
+ /* We need to canonicalize the type name here, because we do lookups
+ using the demangled name, and so we must match the format it
+ uses. E.g., GDB tends to use "const char *" as a type name, but
+ the demangler uses "char const *". */
+ canonical = cp_canonicalize_string (type_name.c_str ());
+ if (!canonical.empty ())
+ type_name = canonical;
+
+ typeinfo_type = gnuv3_get_typeid_type (gdbarch);
+
+ /* We check for lval_memory because in the "typeid (type-id)" case,
+ the type is passed via a not_lval value object. */
+ if (TYPE_CODE (type) == TYPE_CODE_STRUCT
+ && value_lval_const (value) == lval_memory
+ && gnuv3_dynamic_class (type))
+ {
+ struct value *vtable, *typeinfo_value;
+ CORE_ADDR address = value_address (value) + value_embedded_offset (value);
+
+ vtable = gnuv3_get_vtable (gdbarch, type, address);
+ if (vtable == NULL)
+ error (_("cannot find typeinfo for object of type '%s'"),
+ type_name.c_str ());
+ typeinfo_value = value_field (vtable, vtable_field_type_info);
+ result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL),
+ typeinfo_value));
+ }
+ else
+ {
+ std::string sym_name = std::string ("typeinfo for ") + type_name;
+ bound_minimal_symbol minsym
+ = lookup_minimal_symbol (sym_name.c_str (), NULL, NULL);
+
+ if (minsym.minsym == NULL)
+ error (_("could not find typeinfo symbol for '%s'"), type_name.c_str ());
+
+ result = value_at_lazy (typeinfo_type, BMSYMBOL_VALUE_ADDRESS (minsym));
+ }
+
+ return result;
+}
+
+/* Implement the 'get_typename_from_type_info' method. */
+
+static std::string
+gnuv3_get_typename_from_type_info (struct value *type_info_ptr)
+{
+ struct gdbarch *gdbarch = get_type_arch (value_type (type_info_ptr));
+ struct bound_minimal_symbol typeinfo_sym;
+ CORE_ADDR addr;
+ const char *symname;
+ const char *class_name;
+ const char *atsign;
+
+ addr = value_as_address (type_info_ptr);
+ typeinfo_sym = lookup_minimal_symbol_by_pc (addr);
+ if (typeinfo_sym.minsym == NULL)
+ error (_("could not find minimal symbol for typeinfo address %s"),
+ paddress (gdbarch, addr));
+
+#define TYPEINFO_PREFIX "typeinfo for "
+#define TYPEINFO_PREFIX_LEN (sizeof (TYPEINFO_PREFIX) - 1)
+ symname = typeinfo_sym.minsym->demangled_name ();
+ if (symname == NULL || strncmp (symname, TYPEINFO_PREFIX,
+ TYPEINFO_PREFIX_LEN))
+ error (_("typeinfo symbol '%s' has unexpected name"),
+ typeinfo_sym.minsym->linkage_name ());
+ class_name = symname + TYPEINFO_PREFIX_LEN;
+
+ /* Strip off @plt and version suffixes. */
+ atsign = strchr (class_name, '@');
+ if (atsign != NULL)
+ return std::string (class_name, atsign - class_name);
+ return class_name;
+}
+
+/* Implement the 'get_type_from_type_info' method. */
+
+static struct type *
+gnuv3_get_type_from_type_info (struct value *type_info_ptr)
+{
+ /* We have to parse the type name, since in general there is not a
+ symbol for a type. This is somewhat bogus since there may be a
+ mis-parse. Another approach might be to re-use the demangler's
+ internal form to reconstruct the type somehow. */
+ std::string type_name = gnuv3_get_typename_from_type_info (type_info_ptr);
+ expression_up expr (parse_expression (type_name.c_str ()));
+ struct value *type_val = evaluate_type (expr.get ());
+ return value_type (type_val);
+}
+
+/* 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, func_addr;
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct bound_minimal_symbol thunk_sym, fn_sym;
+ struct obj_section *section;
+ const char *thunk_name, *fn_name;
+
+ real_stop_pc = gdbarch_skip_trampoline_code (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.minsym == 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 = thunk_sym.minsym->demangled_name ();
+ 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.minsym == NULL)
+ return 0;
+
+ method_stop_pc = BMSYMBOL_VALUE_ADDRESS (fn_sym);
+
+ /* Some targets have minimal symbols pointing to function descriptors
+ (powerpc 64 for example). Make sure to retrieve the address
+ of the real function from the function descriptor before passing on
+ the address to other layers of GDB. */
+ func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, method_stop_pc,
+ current_top_target ());
+ if (func_addr != 0)
+ method_stop_pc = func_addr;
+
+ real_stop_pc = gdbarch_skip_trampoline_code
+ (gdbarch, frame, method_stop_pc);
+ if (real_stop_pc == 0)
+ real_stop_pc = method_stop_pc;
+
+ return real_stop_pc;
+}
+
+/* A member function is in one these states. */
+
+enum definition_style
+{
+ DOES_NOT_EXIST_IN_SOURCE,
+ DEFAULTED_INSIDE,
+ DEFAULTED_OUTSIDE,
+ DELETED,
+ EXPLICIT,
+};
+
+/* Return how the given field is defined. */
+
+static definition_style
+get_def_style (struct fn_field *fn, int fieldelem)
+{
+ if (TYPE_FN_FIELD_DELETED (fn, fieldelem))
+ return DELETED;
+
+ if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem))
+ return DOES_NOT_EXIST_IN_SOURCE;
+
+ switch (TYPE_FN_FIELD_DEFAULTED (fn, fieldelem))
+ {
+ case DW_DEFAULTED_no:
+ return EXPLICIT;
+ case DW_DEFAULTED_in_class:
+ return DEFAULTED_INSIDE;
+ case DW_DEFAULTED_out_of_class:
+ return DEFAULTED_OUTSIDE;
+ default:
+ break;
+ }
+
+ return EXPLICIT;
+}
+
+/* Helper functions to determine whether the given definition style
+ denotes that the definition is user-provided or implicit.
+ Being defaulted outside the class decl counts as an explicit
+ user-definition, while being defaulted inside is implicit. */
+
+static bool
+is_user_provided_def (definition_style def)
+{
+ return def == EXPLICIT || def == DEFAULTED_OUTSIDE;
+}
+
+static bool
+is_implicit_def (definition_style def)
+{
+ return def == DOES_NOT_EXIST_IN_SOURCE || def == DEFAULTED_INSIDE;
+}
+
+/* Helper function to decide if METHOD_TYPE is a copy/move
+ constructor type for CLASS_TYPE. EXPECTED is the expected
+ type code for the "right-hand-side" argument.
+ This function is supposed to be used by the IS_COPY_CONSTRUCTOR_TYPE
+ and IS_MOVE_CONSTRUCTOR_TYPE functions below. Normally, you should
+ not need to call this directly. */
+
+static bool
+is_copy_or_move_constructor_type (struct type *class_type,
+ struct type *method_type,
+ type_code expected)
+{
+ /* The method should take at least two arguments... */
+ if (TYPE_NFIELDS (method_type) < 2)
+ return false;
+
+ /* ...and the second argument should be the same as the class
+ type, with the expected type code... */
+ struct type *arg_type = TYPE_FIELD_TYPE (method_type, 1);
+
+ if (TYPE_CODE (arg_type) != expected)
+ return false;
+
+ struct type *target = check_typedef (TYPE_TARGET_TYPE (arg_type));
+ if (!(class_types_same_p (target, class_type)))
+ return false;
+
+ /* ...and if any of the remaining arguments don't have a default value
+ then this is not a copy or move constructor, but just a
+ constructor. */
+ for (int i = 2; i < TYPE_NFIELDS (method_type); i++)
+ {
+ arg_type = TYPE_FIELD_TYPE (method_type, i);
+ /* FIXME aktemur/2019-10-31: As of this date, neither
+ clang++-7.0.0 nor g++-8.2.0 produce a DW_AT_default_value
+ attribute. GDB is also not set to read this attribute, yet.
+ Hence, we immediately return false if there are more than
+ 2 parameters.
+ GCC bug link:
+ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42959
+ */
+ return false;
+ }
+
+ return true;
+}
+
+/* Return true if METHOD_TYPE is a copy ctor type for CLASS_TYPE. */
+
+static bool
+is_copy_constructor_type (struct type *class_type,
+ struct type *method_type)
+{
+ return is_copy_or_move_constructor_type (class_type, method_type,
+ TYPE_CODE_REF);
+}
+
+/* Return true if METHOD_TYPE is a move ctor type for CLASS_TYPE. */
+
+static bool
+is_move_constructor_type (struct type *class_type,
+ struct type *method_type)
+{
+ return is_copy_or_move_constructor_type (class_type, method_type,
+ TYPE_CODE_RVALUE_REF);
+}
+
+/* Return pass-by-reference information for the given TYPE.
+
+ The rule in the v3 ABI document comes from section 3.1.1. If the
+ type has a non-trivial copy constructor or destructor, then the
+ caller must make a copy (by calling the copy constructor if there
+ is one or perform the copy itself otherwise), pass the address of
+ the copy, and then destroy the temporary (if necessary).
+
+ For return values with non-trivial copy/move constructors or
+ destructors, space will be allocated in the caller, and a pointer
+ will be passed as the first argument (preceding "this").
+
+ We don't have a bulletproof mechanism for determining whether a
+ constructor or destructor is trivial. For GCC and DWARF5 debug
+ information, we can check the calling_convention attribute,
+ the 'artificial' flag, the 'defaulted' attribute, and the
+ 'deleted' attribute. */
+
+static struct language_pass_by_ref_info
+gnuv3_pass_by_reference (struct type *type)
+{
+ int fieldnum, fieldelem;
+
+ type = check_typedef (type);
+
+ /* Start with the default values. */
+ struct language_pass_by_ref_info info
+ = default_pass_by_reference (type);
+
+ bool has_cc_attr = false;
+ bool is_pass_by_value = false;
+ bool is_dynamic = false;
+ definition_style cctor_def = DOES_NOT_EXIST_IN_SOURCE;
+ definition_style dtor_def = DOES_NOT_EXIST_IN_SOURCE;
+ definition_style mctor_def = DOES_NOT_EXIST_IN_SOURCE;
+
+ /* We're only interested in things that can have methods. */
+ if (TYPE_CODE (type) != TYPE_CODE_STRUCT
+ && TYPE_CODE (type) != TYPE_CODE_UNION)
+ return info;
+
+ /* The compiler may have emitted the calling convention attribute.
+ Note: GCC does not produce this attribute as of version 9.2.1.
+ Bug link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92418 */
+ if (TYPE_CPLUS_CALLING_CONVENTION (type) == DW_CC_pass_by_value)
+ {
+ has_cc_attr = true;
+ is_pass_by_value = true;
+ /* Do not return immediately. We have to find out if this type
+ is copy_constructible and destructible. */
+ }
+
+ if (TYPE_CPLUS_CALLING_CONVENTION (type) == DW_CC_pass_by_reference)
+ {
+ has_cc_attr = true;
+ is_pass_by_value = false;
+ }
+
+ /* A dynamic class has a non-trivial copy constructor.
+ See c++98 section 12.8 Copying class objects [class.copy]. */
+ if (gnuv3_dynamic_class (type))
+ is_dynamic = true;
+
+ for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
+ for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
+ fieldelem++)
+ {
+ struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum);
+ const char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum);
+ struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem);
+
+ if (name[0] == '~')
+ {
+ /* We've found a destructor.
+ There should be at most one dtor definition. */
+ gdb_assert (dtor_def == DOES_NOT_EXIST_IN_SOURCE);
+ dtor_def = get_def_style (fn, fieldelem);
+ }
+ else if (is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem))
+ || TYPE_FN_FIELD_CONSTRUCTOR (fn, fieldelem))
+ {
+ /* FIXME drow/2007-09-23: We could do this using the name of
+ the method and the name of the class instead of dealing
+ with the mangled name. We don't have a convenient function
+ to strip off both leading scope qualifiers and trailing
+ template arguments yet. */
+ if (is_copy_constructor_type (type, fieldtype))
+ {
+ /* There may be more than one cctors. E.g.: one that
+ take a const parameter and another that takes a
+ non-const parameter. Such as:
+
+ class K {
+ K (const K &k)...
+ K (K &k)...
+ };
+
+ It is sufficient for the type to be non-trivial
+ even only one of the cctors is explicit.
+ Therefore, update the cctor_def value in the
+ implicit -> explicit direction, not backwards. */
+
+ if (is_implicit_def (cctor_def))
+ cctor_def = get_def_style (fn, fieldelem);
+ }
+ else if (is_move_constructor_type (type, fieldtype))
+ {
+ /* Again, there may be multiple move ctors. Update the
+ mctor_def value if we found an explicit def and the
+ existing one is not explicit. Otherwise retain the
+ existing value. */
+ if (is_implicit_def (mctor_def))
+ mctor_def = get_def_style (fn, fieldelem);
+ }
+ }
+ }
+
+ bool cctor_implicitly_deleted
+ = (mctor_def != DOES_NOT_EXIST_IN_SOURCE
+ && cctor_def == DOES_NOT_EXIST_IN_SOURCE);
+
+ bool cctor_explicitly_deleted = (cctor_def == DELETED);
+
+ if (cctor_implicitly_deleted || cctor_explicitly_deleted)
+ info.copy_constructible = false;
+
+ if (dtor_def == DELETED)
+ info.destructible = false;
+
+ info.trivially_destructible = is_implicit_def (dtor_def);
+
+ info.trivially_copy_constructible
+ = (is_implicit_def (cctor_def)
+ && !is_dynamic);
+
+ info.trivially_copyable
+ = (info.trivially_copy_constructible
+ && info.trivially_destructible
+ && !is_user_provided_def (mctor_def));
+
+ /* Even if all the constructors and destructors were artificial, one
+ of them may have invoked a non-artificial constructor or
+ destructor in a base class. If any base class needs to be passed
+ by reference, so does this class. Similarly for members, which
+ are constructed whenever this class is. We do not need to worry
+ about recursive loops here, since we are only looking at members
+ of complete class type. Also ignore any static members. */
+ for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++)
+ if (!field_is_static (&TYPE_FIELD (type, fieldnum)))
+ {
+ struct type *field_type = TYPE_FIELD_TYPE (type, fieldnum);
+
+ /* For arrays, make the decision based on the element type. */
+ if (TYPE_CODE (field_type) == TYPE_CODE_ARRAY)
+ field_type = check_typedef (TYPE_TARGET_TYPE (field_type));
+
+ struct language_pass_by_ref_info field_info
+ = gnuv3_pass_by_reference (field_type);
+
+ if (!field_info.copy_constructible)
+ info.copy_constructible = false;
+ if (!field_info.destructible)
+ info.destructible = false;
+ if (!field_info.trivially_copyable)
+ info.trivially_copyable = false;
+ if (!field_info.trivially_copy_constructible)
+ info.trivially_copy_constructible = false;
+ if (!field_info.trivially_destructible)
+ info.trivially_destructible = false;
+ }
+
+ /* Consistency check. */
+ if (has_cc_attr && info.trivially_copyable != is_pass_by_value)
+ {
+ /* DWARF CC attribute is not the same as the inferred value;
+ use the DWARF attribute. */
+ info.trivially_copyable = is_pass_by_value;
+ }
+
+ return info;
+}
+
static void
init_gnuv3_ops (void)
{
- vtable_type_gdbarch_data = register_gdbarch_data (build_gdb_vtable_type, 0);
+ vtable_type_gdbarch_data
+ = gdbarch_data_register_post_init (build_gdb_vtable_type);
+ std_type_info_gdbarch_data
+ = gdbarch_data_register_post_init (build_std_type_info_type);
gnu_v3_abi_ops.shortname = "gnu-v3";
gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI";
gnu_v3_abi_ops.doc = "G++ Version 3 ABI";
- gnu_v3_abi_ops.is_destructor_name = is_gnu_v3_mangled_dtor;
- gnu_v3_abi_ops.is_constructor_name = is_gnu_v3_mangled_ctor;
+ gnu_v3_abi_ops.is_destructor_name =
+ (enum dtor_kinds (*) (const char *))is_gnu_v3_mangled_dtor;
+ gnu_v3_abi_ops.is_constructor_name =
+ (enum ctor_kinds (*) (const char *))is_gnu_v3_mangled_ctor;
gnu_v3_abi_ops.is_vtable_name = gnuv3_is_vtable_name;
gnu_v3_abi_ops.is_operator_name = gnuv3_is_operator_name;
gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type;
gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field;
gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset;
+ gnu_v3_abi_ops.print_method_ptr = gnuv3_print_method_ptr;
+ gnu_v3_abi_ops.method_ptr_size = gnuv3_method_ptr_size;
+ gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr;
+ gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value;
+ gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable;
+ gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid;
+ gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type;
+ gnu_v3_abi_ops.get_type_from_type_info = gnuv3_get_type_from_type_info;
+ gnu_v3_abi_ops.get_typename_from_type_info
+ = gnuv3_get_typename_from_type_info;
+ gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline;
+ gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
}
-
+void _initialize_gnu_v3_abi ();
void
-_initialize_gnu_v3_abi (void)
+_initialize_gnu_v3_abi ()
{
init_gnuv3_ops ();
register_cp_abi (&gnu_v3_abi_ops);
+ set_cp_abi_as_auto_default (gnu_v3_abi_ops.shortname);
}
projects / thirdparty / binutils-gdb.git / blobdiff