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, 2005, 2006, 2007, 2008, 2009, 2010, 2011 7 Free Software Foundation, Inc. 8 9 This file is part of GDB. 10 11 This program is free software; you can redistribute it and/or modify 12 it under the terms of the GNU General Public License as published by 13 the Free Software Foundation; either version 3 of the License, or 14 (at your option) any later version. 15 16 This program is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 GNU General Public License for more details. 20 21 You should have received a copy of the GNU General Public License 22 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 23 24 #ifndef CP_ABI_H_ 25 #define CP_ABI_H_ 1 26 27 struct fn_field; 28 struct type; 29 struct value; 30 struct ui_file; 31 struct frame_info; 32 33 /* The functions here that attempt to determine what sort of thing a 34 mangled name refers to may well be revised in the future. It would 35 certainly be cleaner to carry this information explicitly in GDB's 36 data structures than to derive it from the mangled name. */ 37 38 39 /* Kinds of constructors. All these values are guaranteed to be 40 non-zero. */ 41 enum ctor_kinds { 42 43 /* Initialize a complete object, including virtual bases, using 44 memory provided by caller. */ 45 complete_object_ctor = 1, 46 47 /* Initialize a base object of some larger object. */ 48 base_object_ctor, 49 50 /* An allocating complete-object constructor. */ 51 complete_object_allocating_ctor 52 }; 53 54 /* Return non-zero iff NAME is the mangled name of a constructor. 55 Actually, return an `enum ctor_kind' value describing what *kind* 56 of constructor it is. */ 57 extern enum ctor_kinds is_constructor_name (const char *name); 58 59 60 /* Kinds of destructors. All these values are guaranteed to be 61 non-zero. */ 62 enum dtor_kinds { 63 64 /* A destructor which finalizes the entire object, and then calls 65 `delete' on its storage. */ 66 deleting_dtor = 1, 67 68 /* A destructor which finalizes the entire object, but does not call 69 `delete'. */ 70 complete_object_dtor, 71 72 /* A destructor which finalizes a subobject of some larger 73 object. */ 74 base_object_dtor 75 }; 76 77 /* Return non-zero iff NAME is the mangled name of a destructor. 78 Actually, return an `enum dtor_kind' value describing what *kind* 79 of destructor it is. */ 80 extern enum dtor_kinds is_destructor_name (const char *name); 81 82 83 /* Return non-zero iff NAME is the mangled name of a vtable. */ 84 extern int is_vtable_name (const char *name); 85 86 87 /* Return non-zero iff NAME is the un-mangled name of an operator, 88 perhaps scoped within some class. */ 89 extern int is_operator_name (const char *name); 90 91 92 /* Return an object's virtual function as a value. 93 94 VALUEP is a pointer to a pointer to a value, holding the object 95 whose virtual function we want to invoke. If the ABI requires a 96 virtual function's caller to adjust the `this' pointer by an amount 97 retrieved from the vtable before invoking the function (i.e., we're 98 not using "vtable thunks" to do the adjustment automatically), then 99 this function may set *VALUEP to point to a new object with an 100 appropriately tweaked address. 101 102 The J'th element of the overload set F is the virtual function of 103 *VALUEP we want to invoke. 104 105 TYPE is the base type of *VALUEP whose method we're invoking --- 106 this is the type containing F. OFFSET is the offset of that base 107 type within *VALUEP. */ 108 extern struct value *value_virtual_fn_field (struct value **valuep, 109 struct fn_field *f, 110 int j, 111 struct type *type, 112 int offset); 113 114 115 /* Try to find the run-time type of VALUE, using C++ run-time type 116 information. Return the run-time type, or zero if we can't figure 117 it out. 118 119 If we do find the run-time type: 120 - Set *FULL to non-zero if VALUE already contains the complete 121 run-time object, not just some embedded base class of the object. 122 - Set *TOP and *USING_ENC to indicate where the enclosing object 123 starts relative to VALUE: 124 - If *USING_ENC is zero, then *TOP is the offset from the start 125 of the complete object to the start of the embedded subobject 126 VALUE represents. In other words, the enclosing object starts 127 at VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) + 128 value_embedded_offset (VALUE) + *TOP 129 - If *USING_ENC is non-zero, then *TOP is the offset from the 130 address of the complete object to the enclosing object stored 131 in VALUE. In other words, the enclosing object starts at 132 VALUE_ADDR (VALUE) + VALUE_OFFSET (VALUE) + *TOP. 133 If VALUE's type and enclosing type are the same, then these two 134 cases are equivalent. 135 136 FULL, TOP, and USING_ENC can each be zero, in which case we don't 137 provide the corresponding piece of information. */ 138 extern struct type *value_rtti_type (struct value *value, 139 int *full, int *top, 140 int *using_enc); 141 142 /* Compute the offset of the baseclass which is the INDEXth baseclass 143 of class TYPE, for value at VALADDR (in host) at ADDRESS (in 144 target), offset by EMBEDDED_OFFSET. VALADDR points to the raw 145 contents of VAL. The result is the offset of the baseclass value 146 relative to (the address of)(ARG) + OFFSET. */ 147 148 extern int baseclass_offset (struct type *type, 149 int index, const gdb_byte *valaddr, 150 int embedded_offset, 151 CORE_ADDR address, 152 const struct value *val); 153 154 /* Describe the target of a pointer to method. CONTENTS is the byte 155 pattern representing the pointer to method. TYPE is the pointer to 156 method type. STREAM is the stream to print it to. */ 157 void cplus_print_method_ptr (const gdb_byte *contents, 158 struct type *type, 159 struct ui_file *stream); 160 161 /* Return the size of a pointer to member function of type 162 TO_TYPE. */ 163 int cplus_method_ptr_size (struct type *to_type); 164 165 /* Return the method which should be called by applying METHOD_PTR to 166 *THIS_P, and adjust *THIS_P if necessary. */ 167 struct value *cplus_method_ptr_to_value (struct value **this_p, 168 struct value *method_ptr); 169 170 /* Create the byte pattern in CONTENTS representing a pointer of type 171 TYPE to member function at ADDRESS (if IS_VIRTUAL is 0) or with 172 virtual table offset ADDRESS (if IS_VIRTUAL is 1). This is the 173 opposite of cplus_method_ptr_to_value. */ 174 void cplus_make_method_ptr (struct type *type, gdb_byte *CONTENTS, 175 CORE_ADDR address, int is_virtual); 176 177 /* Determine if we are currently in a C++ thunk. If so, get the 178 address of the routine we are thunking to and continue to there 179 instead. */ 180 181 CORE_ADDR cplus_skip_trampoline (struct frame_info *frame, 182 CORE_ADDR stop_pc); 183 184 /* Return non-zero if an argument of type TYPE should be passed by 185 reference instead of value. */ 186 extern int cp_pass_by_reference (struct type *type); 187 188 struct cp_abi_ops 189 { 190 const char *shortname; 191 const char *longname; 192 const char *doc; 193 194 /* ABI-specific implementations for the functions declared 195 above. */ 196 enum ctor_kinds (*is_constructor_name) (const char *name); 197 enum dtor_kinds (*is_destructor_name) (const char *name); 198 int (*is_vtable_name) (const char *name); 199 int (*is_operator_name) (const char *name); 200 struct value *(*virtual_fn_field) (struct value **arg1p, 201 struct fn_field * f, 202 int j, struct type * type, 203 int offset); 204 struct type *(*rtti_type) (struct value *v, int *full, 205 int *top, int *using_enc); 206 int (*baseclass_offset) (struct type *type, int index, 207 const bfd_byte *valaddr, int embedded_offset, 208 CORE_ADDR address, const struct value *val); 209 void (*print_method_ptr) (const gdb_byte *contents, 210 struct type *type, 211 struct ui_file *stream); 212 int (*method_ptr_size) (struct type *); 213 void (*make_method_ptr) (struct type *, gdb_byte *, 214 CORE_ADDR, int); 215 struct value * (*method_ptr_to_value) (struct value **, 216 struct value *); 217 CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR); 218 int (*pass_by_reference) (struct type *type); 219 }; 220 221 222 extern int register_cp_abi (struct cp_abi_ops *abi); 223 extern void set_cp_abi_as_auto_default (const char *short_name); 224 225 #endif 226 227