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cp-abi.h
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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) 2001-2023 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
25
26struct fn_field;
27struct type;
28struct value;
29struct ui_file;
30class frame_info_ptr;
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. */
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. */
56extern 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. */
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. */
79extern enum dtor_kinds is_destructor_name (const char *name);
80
81
82/* Return non-zero iff NAME is the mangled name of a vtable. */
83extern 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. */
88extern 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. */
107extern 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 () +
127 VALUE->embedded_offset () + *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 () + *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. */
137extern struct type *value_rtti_type (struct value *value,
138 int *full, LONGEST *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
147extern int baseclass_offset (struct type *type,
148 int index, const gdb_byte *valaddr,
149 LONGEST 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. */
156void 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. */
162int 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. */
166struct 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. */
173void 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
179void 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
184extern 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
189extern 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
195extern 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. */
200
201extern std::string cplus_typename_from_type_info (struct value *value);
202
203/* Determine if we are currently in a C++ thunk. If so, get the
204 address of the routine we are thunking to and continue to there
205 instead. */
206
208 CORE_ADDR stop_pc);
209
210/* Return a struct that provides pass-by-reference information
211 about the given TYPE. */
212
214 (struct type *type);
215
217{
218 const char *shortname;
219 const char *longname;
220 const char *doc;
221
222 /* ABI-specific implementations for the functions declared
223 above. */
224 enum ctor_kinds (*is_constructor_name) (const char *name);
225 enum dtor_kinds (*is_destructor_name) (const char *name);
226 int (*is_vtable_name) (const char *name);
227 int (*is_operator_name) (const char *name);
228 struct value *(*virtual_fn_field) (struct value **arg1p,
229 struct fn_field * f,
230 int j, struct type * type,
231 int offset);
232 struct type *(*rtti_type) (struct value *v, int *full,
233 LONGEST *top, int *using_enc);
234 int (*baseclass_offset) (struct type *type, int index,
235 const bfd_byte *valaddr, LONGEST embedded_offset,
236 CORE_ADDR address, const struct value *val);
237 void (*print_method_ptr) (const gdb_byte *contents,
238 struct type *type,
239 struct ui_file *stream);
240 int (*method_ptr_size) (struct type *);
241 void (*make_method_ptr) (struct type *, gdb_byte *,
242 CORE_ADDR, int);
243 struct value * (*method_ptr_to_value) (struct value **,
244 struct value *);
245 void (*print_vtable) (struct value *);
246 struct value *(*get_typeid) (struct value *value);
247 struct type *(*get_typeid_type) (struct gdbarch *gdbarch);
248 struct type *(*get_type_from_type_info) (struct value *value);
249 std::string (*get_typename_from_type_info) (struct value *value);
250 CORE_ADDR (*skip_trampoline) (frame_info_ptr, CORE_ADDR);
252};
253
254
255extern int register_cp_abi (struct cp_abi_ops *abi);
256extern void set_cp_abi_as_auto_default (const char *short_name);
257
258#endif /* CP_ABI_H */
const char *const name
void f()
Definition 1.cc:36
std::string cplus_typename_from_type_info(struct value *value)
Definition cp-abi.c:216
int is_operator_name(const char *name)
Definition cp-abi.c:61
void cplus_print_vtable(struct value *value)
Definition cp-abi.c:176
struct value * cplus_method_ptr_to_value(struct value **this_p, struct value *method_ptr)
Definition cp-abi.c:165
int register_cp_abi(struct cp_abi_ops *abi)
Definition cp-abi.c:252
struct type * cplus_typeid_type(struct gdbarch *gdbarch)
Definition cp-abi.c:196
int cplus_method_ptr_size(struct type *to_type)
Definition cp-abi.c:139
dtor_kinds
Definition cp-abi.h:61
@ base_object_dtor
Definition cp-abi.h:73
@ complete_object_dtor
Definition cp-abi.h:69
@ deleting_dtor
Definition cp-abi.h:65
struct language_pass_by_ref_info cp_pass_by_reference(struct type *type)
Definition cp-abi.c:227
enum dtor_kinds is_destructor_name(const char *name)
Definition cp-abi.c:45
void cplus_make_method_ptr(struct type *type, gdb_byte *CONTENTS, CORE_ADDR address, int is_virtual)
Definition cp-abi.c:147
void cplus_print_method_ptr(const gdb_byte *contents, struct type *type, struct ui_file *stream)
Definition cp-abi.c:129
ctor_kinds
Definition cp-abi.h:40
@ base_object_ctor
Definition cp-abi.h:47
@ complete_object_ctor
Definition cp-abi.h:44
@ complete_object_allocating_ctor
Definition cp-abi.h:50
enum ctor_kinds is_constructor_name(const char *name)
Definition cp-abi.c:37
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
int baseclass_offset(struct type *type, int index, const gdb_byte *valaddr, LONGEST embedded_offset, CORE_ADDR address, const struct value *val)
Definition cp-abi.c:69
void set_cp_abi_as_auto_default(const char *short_name)
Definition cp-abi.c:266
struct type * cplus_type_from_type_info(struct value *value)
Definition cp-abi.c:206
struct type * value_rtti_type(struct value *value, int *full, LONGEST *top, int *using_enc)
Definition cp-abi.c:108
int is_vtable_name(const char *name)
Definition cp-abi.c:53
CORE_ADDR cplus_skip_trampoline(frame_info_ptr frame, CORE_ADDR stop_pc)
Definition cp-abi.c:156
struct value * cplus_typeid(struct value *value)
Definition cp-abi.c:186
int value
Definition py-param.c:79
enum var_types type
Definition scm-param.c:142
const char * shortname
Definition cp-abi.h:218
int(* method_ptr_size)(struct type *)
Definition cp-abi.h:240
CORE_ADDR(* skip_trampoline)(frame_info_ptr, CORE_ADDR)
Definition cp-abi.h:250
void(* make_method_ptr)(struct type *, gdb_byte *, CORE_ADDR, int)
Definition cp-abi.h:241
int(* baseclass_offset)(struct type *type, int index, const bfd_byte *valaddr, LONGEST embedded_offset, CORE_ADDR address, const struct value *val)
Definition cp-abi.h:234
int(* is_vtable_name)(const char *name)
Definition cp-abi.h:226
enum ctor_kinds(* is_constructor_name)(const char *name)
Definition cp-abi.h:224
enum dtor_kinds(* is_destructor_name)(const char *name)
Definition cp-abi.h:225
void(* print_vtable)(struct value *)
Definition cp-abi.h:245
int(* is_operator_name)(const char *name)
Definition cp-abi.h:227
const char * longname
Definition cp-abi.h:219
const char * doc
Definition cp-abi.h:220
struct language_pass_by_ref_info(* pass_by_reference)(struct type *type)
Definition cp-abi.h:251
std::string(* get_typename_from_type_info)(struct value *value)
Definition cp-abi.h:249
void(* print_method_ptr)(const gdb_byte *contents, struct type *type, struct ui_file *stream)
Definition cp-abi.h:237
Definition value.h:130
LONGEST offset() const
Definition value.h:222
CORE_ADDR address
Definition value.h:658