gdb/cp-abi.h

   1 /* Abstraction of various C++ ABI's we support, and the info we need
   2    to get from them.
   3    Contributed by Daniel Berlin <dberlin@redhat.com>
   4    Copyright 2001 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or
   9    modify
  10    it under the terms of the GNU General Public License as published
  11    by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  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.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25 #ifndef CP_ABI_H_
  26 #define CP_ABI_H_ 1
  27
  28 struct value;
  29
  30 /* The functions here that attempt to determine what sort of thing a
  31    mangled name refers to may well be revised in the future.  It would
  32    certainly be cleaner to carry this information explicitly in GDB's
  33    data structures than to derive it from the mangled name.  */
  34
  35
  36 /* Kinds of constructors.  All these values are guaranteed to be
  37    non-zero.  */
  38 enum ctor_kinds {
  39
  40   /* Initialize a complete object, including virtual bases, using
  41      memory provided by caller.  */
  42   complete_object_ctor = 1,
  43
  44   /* Initialize a base object of some larger object.  */
  45   base_object_ctor,
  46
  47   /* An allocating complete-object constructor.  */
  48   complete_object_allocating_ctor
  49 };
  50
  51 /* Return non-zero iff NAME is the mangled name of a constructor.
  52    Actually, return an `enum ctor_kind' value describing what *kind*
  53    of constructor it is.  */
  54 extern enum ctor_kinds is_constructor_name (const char *name);
  55
  56
  57 /* Kinds of destructors.  All these values are guaranteed to be
  58    non-zero.  */
  59 enum dtor_kinds {
  60
  61   /* A destructor which finalizes the entire object, and then calls
  62      `delete' on its storage.  */
  63   deleting_dtor = 1,
  64
  65   /* A destructor which finalizes the entire object, but does not call
  66      `delete'.  */
  67   complete_object_dtor,
  68
  69   /* A destructor which finalizes a subobject of some larger object.  */
  70   base_object_dtor
  71 };
  72
  73 /* Return non-zero iff NAME is the mangled name of a destructor.
  74    Actually, return an `enum dtor_kind' value describing what *kind*
  75    of destructor it is.  */
  76 extern enum dtor_kinds is_destructor_name (const char *name);
  77
  78
  79 /* Return non-zero iff NAME is the mangled name of a vtable.  */
  80 extern int is_vtable_name (const char *name);
  81
  82
  83 /* Return non-zero iff NAME is the un-mangled name of an operator,
  84    perhaps scoped within some class.  */
  85 extern int is_operator_name (const char *name);
  86
  87
  88 /* Return an object's virtual function as a value.
  89
  90    VALUEP is a pointer to a pointer to a value, holding the object
  91    whose virtual function we want to invoke.  If the ABI requires a
  92    virtual function's caller to adjust the `this' pointer by an amount
  93    retrieved from the vtable before invoking the function (i.e., we're
  94    not using "vtable thunks" to do the adjustment automatically), then
  95    this function may set *VALUEP to point to a new object with an
  96    appropriately tweaked address.
  97
  98    The J'th element of the overload set F is the virtual function of
  99    *VALUEP we want to invoke.
 100
 101    TYPE is the base type of *VALUEP whose method we're invoking ---
 102    this is the type containing F.  OFFSET is the offset of that base
 103    type within *VALUEP.  */
 104 extern struct value *value_virtual_fn_field (struct value **valuep,
 105                                              struct fn_field *f, int j,
 106                                              struct type *type, int offset);
 107
 108
 109 /* Try to find the run-time type of VALUE, using C++ run-time type
 110    information.  Return the run-time type, or zero if we can't figure
 111    it out.
 112
 113    If we do find the run-time type:
 114    - Set *FULL to non-zero if VALUE already contains the complete
 115      run-time object, not just some embedded base class of the object.
 116    - Set *TOP and *USING_ENC to indicate where the enclosing object
 117      starts relative to VALUE:
 118      - If *USING_ENC is zero, then *TOP is the offset from the start
 119        of the complete object to the start of the embedded subobject
 120        VALUE represents.  In other words, the enclosing object starts
 121        at VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) +
 122        VALUE_EMBEDDED_OFFSET (VALUE) + *TOP
 123      - If *USING_ENC is non-zero, then *TOP is the offset from the
 124        address of the complete object to the enclosing object stored
 125        in VALUE.  In other words, the enclosing object starts at
 126        VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) + *TOP.
 127      If VALUE's type and enclosing type are the same, then these two
 128      cases are equivalent.
 129
 130    FULL, TOP, and USING_ENC can each be zero, in which case we don't
 131    provide the corresponding piece of information.  */
 132 extern struct type *value_rtti_type (struct value *value,
 133                                      int *full, int *top, int *using_enc);
 134
 135 /* Compute the offset of the baseclass which is
 136    the INDEXth baseclass of class TYPE,
 137    for value at VALADDR (in host) at ADDRESS (in target).
 138    The result is the offset of the baseclass value relative
 139    to (the address of)(ARG) + OFFSET.
 140
 141    -1 is returned on error. */
 142
 143 extern int baseclass_offset (struct type *type, int index, char *valaddr,
 144                              CORE_ADDR address);
 145
 146 struct cp_abi_ops
 147 {
 148   const char *shortname;
 149   const char *longname;
 150   const char *doc;
 151
 152   /* ABI-specific implementations for the functions declared above.  */
 153   enum ctor_kinds (*is_constructor_name) (const char *name);
 154   enum dtor_kinds (*is_destructor_name) (const char *name);
 155   int (*is_vtable_name) (const char *name);
 156   int (*is_operator_name) (const char *name);
 157   struct value *(*virtual_fn_field) (struct value **arg1p, struct fn_field * f,
 158                                      int j, struct type * type, int offset);
 159   struct type *(*rtti_type) (struct value *v, int *full, int *top,
 160                              int *using_enc);
 161   int (*baseclass_offset) (struct type *type, int index, char *valaddr,
 162                            CORE_ADDR address);
 163 };
 164
 165
 166 extern struct cp_abi_ops *cp_abis;
 167 extern int num_cp_abis;
 168 extern struct cp_abi_ops current_cp_abi;
 169 extern int register_cp_abi (struct cp_abi_ops abi);
 170 extern int switch_to_cp_abi (const char *short_name);
 171
 172 #endif
 173