| 1 | /* Definitions for values of C expressions, for GDB. |
| 2 | Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | GDB is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 1, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GDB is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GDB; see the file COPYING. If not, write to |
| 18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 19 | |
| 20 | /* |
| 21 | * The structure which defines the type of a value. It should never |
| 22 | * be possible for a program lval value to survive over a call to the inferior |
| 23 | * (ie to be put into the history list or an internal variable). |
| 24 | */ |
| 25 | enum lval_type { |
| 26 | /* Not an lval. */ |
| 27 | not_lval, |
| 28 | /* In memory. Could be a saved register. */ |
| 29 | lval_memory, |
| 30 | /* In a register. */ |
| 31 | lval_register, |
| 32 | /* In a gdb internal variable. */ |
| 33 | lval_internalvar, |
| 34 | /* Part of a gdb internal variable (structure field). */ |
| 35 | lval_internalvar_component, |
| 36 | /* In a register series in a frame not the current one, which may have been |
| 37 | partially saved or saved in different places (otherwise would be |
| 38 | lval_register or lval_memory). */ |
| 39 | lval_reg_frame_relative, |
| 40 | }; |
| 41 | |
| 42 | struct value |
| 43 | { |
| 44 | /* Type of value; either not an lval, or one of the various |
| 45 | different possible kinds of lval. */ |
| 46 | enum lval_type lval; |
| 47 | /* Location of value (if lval). */ |
| 48 | union |
| 49 | { |
| 50 | /* Address in inferior or byte of registers structure. */ |
| 51 | CORE_ADDR address; |
| 52 | /* Pointer to interrnal variable. */ |
| 53 | struct internalvar *internalvar; |
| 54 | /* Number of register. Only used with |
| 55 | lval_reg_frame_relative. */ |
| 56 | int regnum; |
| 57 | } location; |
| 58 | /* Describes offset of a value within lval a structure in bytes. */ |
| 59 | int offset; |
| 60 | /* Only used for bitfields; number of bits contained in them. */ |
| 61 | int bitsize; |
| 62 | /* Only used for bitfields; position of start of field. */ |
| 63 | int bitpos; |
| 64 | /* Frame value is relative to. In practice, this address is only |
| 65 | used if the value is stored in several registers in other than |
| 66 | the current frame, and these registers have not all been saved |
| 67 | at the same place in memory. This will be described in the |
| 68 | lval enum above as "lval_reg_frame_relative". */ |
| 69 | CORE_ADDR frame_addr; |
| 70 | /* Type of the value. */ |
| 71 | struct type *type; |
| 72 | /* Values are stored in a chain, so that they can be deleted |
| 73 | easily over calls to the inferior. Values assigned to internal |
| 74 | variables or put into the value history are taken off this |
| 75 | list. */ |
| 76 | struct value *next; |
| 77 | /* If an lval is forced to repeat, a new value is created with |
| 78 | these fields set. The new value is not an lval. */ |
| 79 | short repeated; |
| 80 | short repetitions; |
| 81 | /* Register number if the value is from a register. Is not kept |
| 82 | if you take a field of a structure that is stored in a |
| 83 | register. Shouldn't it be? */ |
| 84 | short regno; |
| 85 | /* Actual contents of the value. For use of this value; setting |
| 86 | it uses the stuff above. */ |
| 87 | long contents[1]; |
| 88 | }; |
| 89 | |
| 90 | typedef struct value *value; |
| 91 | |
| 92 | #define VALUE_TYPE(val) (val)->type |
| 93 | #define VALUE_CONTENTS(val) ((char *) (val)->contents) |
| 94 | #define VALUE_LVAL(val) (val)->lval |
| 95 | #define VALUE_ADDRESS(val) (val)->location.address |
| 96 | #define VALUE_INTERNALVAR(val) (val)->location.internalvar |
| 97 | #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum) |
| 98 | #define VALUE_FRAME(val) ((val)->frame_addr) |
| 99 | #define VALUE_OFFSET(val) (val)->offset |
| 100 | #define VALUE_BITSIZE(val) (val)->bitsize |
| 101 | #define VALUE_BITPOS(val) (val)->bitpos |
| 102 | #define VALUE_NEXT(val) (val)->next |
| 103 | #define VALUE_REPEATED(val) (val)->repeated |
| 104 | #define VALUE_REPETITIONS(val) (val)->repetitions |
| 105 | #define VALUE_REGNO(val) (val)->regno |
| 106 | |
| 107 | /* If ARG is an array, convert it to a pointer. |
| 108 | If ARG is an enum, convert it to an integer. |
| 109 | |
| 110 | References are dereferenced. */ |
| 111 | |
| 112 | #define COERCE_ARRAY(arg) \ |
| 113 | { if (TYPE_CODE ( VALUE_TYPE (arg)) == TYPE_CODE_REF) \ |
| 114 | arg = value_ind (arg); \ |
| 115 | if (VALUE_REPEATED (arg) \ |
| 116 | || TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \ |
| 117 | arg = value_coerce_array (arg); \ |
| 118 | if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ENUM) \ |
| 119 | arg = value_cast (builtin_type_unsigned_int, arg); \ |
| 120 | } |
| 121 | |
| 122 | /* If ARG is an enum, convert it to an integer. */ |
| 123 | |
| 124 | #define COERCE_ENUM(arg) \ |
| 125 | { if (TYPE_CODE ( VALUE_TYPE (arg)) == TYPE_CODE_REF) \ |
| 126 | arg = value_ind (arg); \ |
| 127 | if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ENUM) \ |
| 128 | arg = value_cast (builtin_type_unsigned_int, arg); \ |
| 129 | } |
| 130 | |
| 131 | /* Internal variables (variables for convenience of use of debugger) |
| 132 | are recorded as a chain of these structures. */ |
| 133 | |
| 134 | struct internalvar |
| 135 | { |
| 136 | struct internalvar *next; |
| 137 | char *name; |
| 138 | value value; |
| 139 | }; |
| 140 | \f |
| 141 | LONGEST value_as_long (); |
| 142 | double value_as_double (); |
| 143 | LONGEST unpack_long (); |
| 144 | double unpack_double (); |
| 145 | long unpack_field_as_long (); |
| 146 | value value_from_long (); |
| 147 | value value_from_double (); |
| 148 | value value_at (); |
| 149 | value value_from_register (); |
| 150 | value value_of_variable (); |
| 151 | value value_of_register (); |
| 152 | value read_var_value (); |
| 153 | value locate_var_value (); |
| 154 | value allocate_value (); |
| 155 | value allocate_repeat_value (); |
| 156 | value value_string (); |
| 157 | |
| 158 | value value_binop (); |
| 159 | value value_add (); |
| 160 | value value_sub (); |
| 161 | value value_coerce_array (); |
| 162 | value value_ind (); |
| 163 | value value_addr (); |
| 164 | value value_assign (); |
| 165 | value value_neg (); |
| 166 | value value_lognot (); |
| 167 | value value_struct_elt (), value_struct_elt_for_address (); |
| 168 | value value_field (); |
| 169 | value value_cast (); |
| 170 | value value_zero (); |
| 171 | value value_repeat (); |
| 172 | value value_subscript (); |
| 173 | |
| 174 | value call_function (); |
| 175 | value value_being_returned (); |
| 176 | int using_struct_return (); |
| 177 | |
| 178 | value evaluate_expression (); |
| 179 | value evaluate_type (); |
| 180 | value parse_and_eval (); |
| 181 | value parse_to_comma_and_eval (); |
| 182 | |
| 183 | value access_value_history (); |
| 184 | value value_of_internalvar (); |
| 185 | struct internalvar *lookup_internalvar (); |
| 186 | |
| 187 | int value_equal (); |
| 188 | int value_less (); |
| 189 | int value_zerop (); |
| 190 | |
| 191 | /* C++ */ |
| 192 | value value_of_this (); |
| 193 | value value_static_field (); |
| 194 | value value_x_binop (); |
| 195 | value value_x_unop (); |
| 196 | int binop_user_defined_p (); |
| 197 | int unop_user_defined_p (); |
| 198 | |
| 199 | void read_register_bytes (); |
| 200 | void modify_field (); |
| 201 | void type_print (); |
| 202 | void type_print_1 (); |
| 203 | |
| 204 | /* Possibilities for prettyprint parameters to routines which print |
| 205 | things. */ |
| 206 | enum val_prettyprint { |
| 207 | Val_no_prettyprint = 0, |
| 208 | Val_prettyprint, |
| 209 | /* Use the default setting which the user has specified. */ |
| 210 | Val_pretty_default |
| 211 | }; |
| 212 | |