gdb/cp-abi.h - gdb

Data types defined

Macros defined

Source code

  1. /* Abstraction of various C++ ABI's we support, and the info we need
  2.    to get from them.

  4.    Contributed by Daniel Berlin <dberlin@redhat.com>

  6.    Copyright (C) 2001-2015 Free Software Foundation, Inc.

  8.    This file is part of GDB.

  10.    This program is free software; you can redistribute it and/or modify
  11.    it under the terms of the GNU General Public License as published by
  12.    the Free Software Foundation; either version 3 of the License, or
  13.    (at your option) any later version.

  15.    This program is distributed in the hope that it will be useful,
  16.    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17.    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18.    GNU General Public License for more details.

  20.    You should have received a copy of the GNU General Public License
  21.    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

  23. #ifndef CP_ABI_H_
  24. ‌#define CP_ABI_H_ 1

  26. struct fn_field;
  27. struct type;
  28. struct value;
  29. struct ui_file;
  30. struct frame_info;

  32. /* The functions here that attempt to determine what sort of thing a
  33.    mangled name refers to may well be revised in the future.  It would
  34.    certainly be cleaner to carry this information explicitly in GDB's
  35.    data structures than to derive it from the mangled name.  */


  38. /* Kinds of constructors.  All these values are guaranteed to be
  39.    non-zero.  */
  40. ‌enum ctor_kinds {

  42.   /* Initialize a complete object, including virtual bases, using
  43.      memory provided by caller.  */
  44.   complete_object_ctor = 1,

  46.   /* Initialize a base object of some larger object.  */
  47.   base_object_ctor,

  49.   /* An allocating complete-object constructor.  */
  50.   complete_object_allocating_ctor
  51. };

  53. /* Return non-zero iff NAME is the mangled name of a constructor.
  54.    Actually, return an `enum ctor_kind' value describing what *kind*
  55.    of constructor it is.  */
  56. extern enum ctor_kinds is_constructor_name (const char *name);


  59. /* Kinds of destructors.  All these values are guaranteed to be
  60.    non-zero.  */
  61. ‌enum dtor_kinds {

  63.   /* A destructor which finalizes the entire object, and then calls
  64.      `delete' on its storage.  */
  65.   deleting_dtor = 1,

  67.   /* A destructor which finalizes the entire object, but does not call
  68.      `delete'.  */
  69.   complete_object_dtor,

  71.   /* A destructor which finalizes a subobject of some larger
  72.      object.  */
  73.   base_object_dtor
  74. };

  76. /* Return non-zero iff NAME is the mangled name of a destructor.
  77.    Actually, return an `enum dtor_kind' value describing what *kind*
  78.    of destructor it is.  */
  79. extern enum dtor_kinds is_destructor_name (const char *name);


  82. /* Return non-zero iff NAME is the mangled name of a vtable.  */
  83. extern int is_vtable_name (const char *name);


  86. /* Return non-zero iff NAME is the un-mangled name of an operator,
  87.    perhaps scoped within some class.  */
  88. extern int is_operator_name (const char *name);


  91. /* Return an object's virtual function as a value.

  93.    VALUEP is a pointer to a pointer to a value, holding the object
  94.    whose virtual function we want to invoke.  If the ABI requires a
  95.    virtual function's caller to adjust the `this' pointer by an amount
  96.    retrieved from the vtable before invoking the function (i.e., we're
  97.    not using "vtable thunks" to do the adjustment automatically), then
  98.    this function may set *VALUEP to point to a new object with an
  99.    appropriately tweaked address.

  101.    The J'th element of the overload set F is the virtual function of
  102.    *VALUEP we want to invoke.

  104.    TYPE is the base type of *VALUEP whose method we're invoking ---
  105.    this is the type containing F.  OFFSET is the offset of that base
  106.    type within *VALUEP.  */
  107. extern struct value *value_virtual_fn_field (struct value **valuep,
  108.                                              struct fn_field *f,
  109.                                              int j,
  110.                                              struct type *type,
  111.                                              int offset);


  114. /* Try to find the run-time type of VALUE, using C++ run-time type
  115.    information.  Return the run-time type, or zero if we can't figure
  116.    it out.

  118.    If we do find the run-time type:
  119.    - Set *FULL to non-zero if VALUE already contains the complete
  120.      run-time object, not just some embedded base class of the object.
  121.    - Set *TOP and *USING_ENC to indicate where the enclosing object
  122.      starts relative to VALUE:
  123.      - If *USING_ENC is zero, then *TOP is the offset from the start
  124.        of the complete object to the start of the embedded subobject
  125.        VALUE represents.  In other words, the enclosing object starts
  126.        at VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) +
  127.        value_embedded_offset (VALUE) + *TOP
  128.      - If *USING_ENC is non-zero, then *TOP is the offset from the
  129.        address of the complete object to the enclosing object stored
  130.        in VALUE.  In other words, the enclosing object starts at
  131.        VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) + *TOP.
  132.      If VALUE's type and enclosing type are the same, then these two
  133.      cases are equivalent.

  135.    FULL, TOP, and USING_ENC can each be zero, in which case we don't
  136.    provide the corresponding piece of information.  */
  137. extern struct type *value_rtti_type (struct value *value,
  138.                                      int *full, int *top,
  139.                                      int *using_enc);

  141. /* Compute the offset of the baseclass which is the INDEXth baseclass
  142.    of class TYPE, for value at VALADDR (in host) at ADDRESS (in
  143.    target), offset by EMBEDDED_OFFSET.  VALADDR points to the raw
  144.    contents of VAL.  The result is the offset of the baseclass value
  145.    relative to (the address of)(ARG) + OFFSET.  */

  147. extern int baseclass_offset (struct type *type,
  148.                              int index, const gdb_byte *valaddr,
  149.                              int embedded_offset,
  150.                              CORE_ADDR address,
  151.                              const struct value *val);

  153. /* Describe the target of a pointer to method.  CONTENTS is the byte
  154.    pattern representing the pointer to method.  TYPE is the pointer to
  155.    method type.  STREAM is the stream to print it to.  */
  156. void cplus_print_method_ptr (const gdb_byte *contents,
  157.                              struct type *type,
  158.                              struct ui_file *stream);

  160. /* Return the size of a pointer to member function of type
  161.    TO_TYPE.  */
  162. int cplus_method_ptr_size (struct type *to_type);

  164. /* Return the method which should be called by applying METHOD_PTR to
  165.    *THIS_P, and adjust *THIS_P if necessary.  */
  166. struct value *cplus_method_ptr_to_value (struct value **this_p,
  167.                                          struct value *method_ptr);

  169. /* Create the byte pattern in CONTENTS representing a pointer of type
  170.    TYPE to member function at ADDRESS (if IS_VIRTUAL is 0) or with
  171.    virtual table offset ADDRESS (if IS_VIRTUAL is 1).  This is the
  172.    opposite of cplus_method_ptr_to_value.  */
  173. void cplus_make_method_ptr (struct type *type, gdb_byte *CONTENTS,
  174.                             CORE_ADDR address, int is_virtual);

  176. /* Print the vtable for VALUE, if there is one.  If there is no
  177.    vtable, print a message, but do not throw.  */

  179. void cplus_print_vtable (struct value *value);

  181. /* Implement 'typeid': find the type info for VALUE, if possible.  If
  182.    the type info cannot be found, throw an exception.  */

  184. extern struct value *cplus_typeid (struct value *value);

  186. /* Return the type of 'typeid' for the current C++ ABI on the given
  187.    architecture.  */

  189. extern struct type *cplus_typeid_type (struct gdbarch *gdbarch);

  191. /* Given a value which holds a pointer to a std::type_info, return the
  192.    type which that type_info represents.  Throw an exception if the
  193.    type cannot be found.  */

  195. extern struct type *cplus_type_from_type_info (struct value *value);

  197. /* Given a value which holds a pointer to a std::type_info, return the
  198.    name of the type which that type_info represents.  Throw an
  199.    exception if the type name cannot be found.  The result is
  200.    xmalloc'd and must be freed by the caller.  */

  202. extern char *cplus_typename_from_type_info (struct value *value);

  204. /* Determine if we are currently in a C++ thunk.  If so, get the
  205.    address of the routine we are thunking to and continue to there
  206.    instead.  */

  208. CORE_ADDR cplus_skip_trampoline (struct frame_info *frame,
  209.                                  CORE_ADDR stop_pc);

  211. /* Return non-zero if an argument of type TYPE should be passed by
  212.    reference instead of value.  */
  213. extern int cp_pass_by_reference (struct type *type);

  215. ‌struct cp_abi_ops
  216. {
  217.   const char *shortname;
  218.   const char *longname;
  219.   const char *doc;

  221.   /* ABI-specific implementations for the functions declared
  222.      above.  */
  223.   enum ctor_kinds (*is_constructor_name) (const char *name);
  224.   enum dtor_kinds (*is_destructor_name) (const char *name);
  225.   int (*is_vtable_name) (const char *name);
  226.   int (*is_operator_name) (const char *name);
  227.   struct value *(*virtual_fn_field) (struct value **arg1p,
  228.                                      struct fn_field * f,
  229.                                      int j, struct type * type,
  230.                                      int offset);
  231.   struct type *(*rtti_type) (struct value *v, int *full,
  232.                              int *top, int *using_enc);
  233.   int (*baseclass_offset) (struct type *type, int index,
  234.                            const bfd_byte *valaddr, int embedded_offset,
  235.                            CORE_ADDR address, const struct value *val);
  236.   void (*print_method_ptr) (const gdb_byte *contents,
  237.                             struct type *type,
  238.                             struct ui_file *stream);
  239.   int (*method_ptr_size) (struct type *);
  240.   void (*make_method_ptr) (struct type *, gdb_byte *,
  241.                            CORE_ADDR, int);
  242.   struct value * (*method_ptr_to_value) (struct value **,
  243.                                          struct value *);
  244.   void (*print_vtable) (struct value *);
  245.   struct value *(*get_typeid) (struct value *value);
  246.   struct type *(*get_typeid_type) (struct gdbarch *gdbarch);
  247.   struct type *(*get_type_from_type_info) (struct value *value);
  248.   char *(*get_typename_from_type_info) (struct value *value);
  249.   CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
  250.   int (*pass_by_reference) (struct type *type);
  251. };


  254. extern int register_cp_abi (struct cp_abi_ops *abi);
  255. extern void set_cp_abi_as_auto_default (const char *short_name);

  257. #endif