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1 /* Abstraction of various C++ ABI's we support, and the info we need
2  to get from them.
3 
4  Contributed by Daniel Berlin <dberlin@redhat.com>
5 
6  Copyright (C) 2001-2015 Free Software Foundation, Inc.
7 
8  This file is part of GDB.
9 
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.
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, see <http://www.gnu.org/licenses/>. */
22 
23 #ifndef CP_ABI_H_
24 #define CP_ABI_H_ 1
25 
26 struct fn_field;
27 struct type;
28 struct value;
29 struct ui_file;
30 struct frame_info;
31 
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. */
36 
37 
38 /* Kinds of constructors. All these values are guaranteed to be
39  non-zero. */
40 enum ctor_kinds {
41 
42  /* Initialize a complete object, including virtual bases, using
43  memory provided by caller. */
45 
46  /* Initialize a base object of some larger object. */
48 
49  /* An allocating complete-object constructor. */
51 };
52 
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);
57 
58 
59 /* Kinds of destructors. All these values are guaranteed to be
60  non-zero. */
61 enum dtor_kinds {
62 
63  /* A destructor which finalizes the entire object, and then calls
64  `delete' on its storage. */
66 
67  /* A destructor which finalizes the entire object, but does not call
68  `delete'. */
70 
71  /* A destructor which finalizes a subobject of some larger
72  object. */
74 };
75 
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);
80 
81 
82 /* Return non-zero iff NAME is the mangled name of a vtable. */
83 extern int is_vtable_name (const char *name);
84 
85 
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);
89 
90 
91 /* Return an object's virtual function as a value.
92 
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.
100 
101  The J'th element of the overload set F is the virtual function of
102  *VALUEP we want to invoke.
103 
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);
112 
113 
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.
117 
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.
134 
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);
140 
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. */
146 
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);
152 
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);
159 
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);
163 
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);
168 
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);
175 
176 /* Print the vtable for VALUE, if there is one. If there is no
177  vtable, print a message, but do not throw. */
178 
179 void cplus_print_vtable (struct value *value);
180 
181 /* Implement 'typeid': find the type info for VALUE, if possible. If
182  the type info cannot be found, throw an exception. */
183 
184 extern struct value *cplus_typeid (struct value *value);
185 
186 /* Return the type of 'typeid' for the current C++ ABI on the given
187  architecture. */
188 
189 extern struct type *cplus_typeid_type (struct gdbarch *gdbarch);
190 
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. */
194 
195 extern struct type *cplus_type_from_type_info (struct value *value);
196 
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. */
201 
202 extern char *cplus_typename_from_type_info (struct value *value);
203 
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. */
207 
210 
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);
214 
216 {
217  const char *shortname;
218  const char *longname;
219  const char *doc;
220 
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);
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);
250  int (*pass_by_reference) (struct type *type);
251 };
252 
253 
254 extern int register_cp_abi (struct cp_abi_ops *abi);
255 extern void set_cp_abi_as_auto_default (const char *short_name);
256 
257 #endif
258 
int baseclass_offset(struct type *type, int index, const gdb_byte *valaddr, int embedded_offset, CORE_ADDR address, const struct value *val)
Definition: cp-abi.c:68
const char * doc
Definition: cp-abi.h:219
int(* is_vtable_name)(const char *name)
Definition: cp-abi.h:225
struct value * value_virtual_fn_field(struct value **valuep, struct fn_field *f, int j, struct type *type, int offset)
Definition: cp-abi.c:97
bfd_vma CORE_ADDR
Definition: common-types.h:41
enum dtor_kinds is_destructor_name(const char *name)
Definition: cp-abi.c:44
struct value * cplus_typeid(struct value *value)
Definition: cp-abi.c:186
int(* method_ptr_size)(struct type *)
Definition: cp-abi.h:239
enum ctor_kinds(* is_constructor_name)(const char *name)
Definition: cp-abi.h:223
void(* print_vtable)(struct value *)
Definition: cp-abi.h:244
int is_vtable_name(const char *name)
Definition: cp-abi.c:52
enum dtor_kinds(* is_destructor_name)(const char *name)
Definition: cp-abi.h:224
void cplus_print_method_ptr(const gdb_byte *contents, struct type *type, struct ui_file *stream)
Definition: cp-abi.c:129
void cplus_make_method_ptr(struct type *type, gdb_byte *CONTENTS, CORE_ADDR address, int is_virtual)
Definition: cp-abi.c:147
gdb_byte * contents
Definition: value.c:323
const char *const name
Definition: aarch64-tdep.c:68
dtor_kinds
Definition: cp-abi.h:61
struct value * cplus_method_ptr_to_value(struct value **this_p, struct value *method_ptr)
Definition: cp-abi.c:165
Definition: gdbtypes.h:749
int(* baseclass_offset)(struct type *type, int index, const bfd_byte *valaddr, int embedded_offset, CORE_ADDR address, const struct value *val)
Definition: cp-abi.h:233
const char * longname
Definition: cp-abi.h:218
static const char * type
Definition: language.c:103
int cp_pass_by_reference(struct type *type)
Definition: cp-abi.c:225
void(* print_method_ptr)(const gdb_byte *contents, struct type *type, struct ui_file *stream)
Definition: cp-abi.h:236
Definition: value.c:172
int register_cp_abi(struct cp_abi_ops *abi)
Definition: cp-abi.c:250
void cplus_print_vtable(struct value *value)
Definition: cp-abi.c:176
enum ctor_kinds is_constructor_name(const char *name)
Definition: cp-abi.c:36
const char const char int
Definition: command.h:229
bfd_byte gdb_byte
Definition: common-types.h:38
int(* is_operator_name)(const char *name)
Definition: cp-abi.h:226
char * cplus_typename_from_type_info(struct value *value)
Definition: cp-abi.c:216
ctor_kinds
Definition: cp-abi.h:40
int offset
Definition: agent.c:65
CORE_ADDR cplus_skip_trampoline(struct frame_info *frame, CORE_ADDR stop_pc)
Definition: cp-abi.c:156
CORE_ADDR stop_pc
Definition: infcmd.c:128
const char * shortname
Definition: cp-abi.h:217
void set_cp_abi_as_auto_default(const char *short_name)
Definition: cp-abi.c:265
int(* pass_by_reference)(struct type *type)
Definition: cp-abi.h:250
struct type * cplus_type_from_type_info(struct value *value)
Definition: cp-abi.c:206
int cplus_method_ptr_size(struct type *to_type)
Definition: cp-abi.c:139
void(* make_method_ptr)(struct type *, gdb_byte *, CORE_ADDR, int)
Definition: cp-abi.h:240
struct type * cplus_typeid_type(struct gdbarch *gdbarch)
Definition: cp-abi.c:196
CORE_ADDR address
Definition: value.c:216
int is_operator_name(const char *name)
Definition: cp-abi.c:60
CORE_ADDR(* skip_trampoline)(struct frame_info *, CORE_ADDR)
Definition: cp-abi.h:249
struct type * value_rtti_type(struct value *value, int *full, int *top, int *using_enc)
Definition: cp-abi.c:108