| 1 | /* Definitions for dealing with stack frames, for GDB, the GNU debugger. |
| 2 | Copyright 1986, 1989, 1991, 1992 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program 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 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program 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 this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 19 | |
| 20 | #if !defined (FRAME_H) |
| 21 | #define FRAME_H 1 |
| 22 | |
| 23 | /* A FRAME identifies a specific stack frame. It is not constant over |
| 24 | calls to the inferior (frame addresses are, see below). |
| 25 | |
| 26 | This is implemented as a "struct frame_info *". This file and |
| 27 | blockframe.c are the only places which are allowed to use the |
| 28 | equivalence between FRAME and struct frame_info *. Exception: |
| 29 | Prototypes in other files use "struct frame_info *" because this |
| 30 | file might not be included. |
| 31 | |
| 32 | The distinction between a FRAME and a "struct frame_info *" is made |
| 33 | with the idea of maybe someday changing a FRAME to be something else, |
| 34 | but seems to me that a "struct frame_info *" is fully general (since |
| 35 | any necessarily fields can be added; changing the meaning of existing |
| 36 | fields is not helped by the FRAME distinction), and this distinction |
| 37 | merely creates unnecessary hair. -kingdon, 18 May 93. */ |
| 38 | typedef struct frame_info *FRAME; |
| 39 | |
| 40 | /* Convert from a "struct frame_info *" into a FRAME. */ |
| 41 | #define FRAME_INFO_ID(f) (f) |
| 42 | |
| 43 | /* Convert from a FRAME into a "struct frame_info *". */ |
| 44 | extern struct frame_info * |
| 45 | get_frame_info PARAMS ((FRAME)); |
| 46 | |
| 47 | /* Type of the address of a frame. It is widely assumed (at least in |
| 48 | prototypes in headers which might not include this header) that |
| 49 | this is the same as CORE_ADDR, and no one can think of a case in |
| 50 | which it wouldn't be, so it might be best to remove this typedef. */ |
| 51 | typedef CORE_ADDR FRAME_ADDR; |
| 52 | |
| 53 | /* Convert from a FRAME into a frame address. Except in the |
| 54 | machine-dependent *FRAME* macros, a frame address has no defined |
| 55 | meaning other than as a magic cookie which identifies a frame over |
| 56 | calls to the inferior. The only known exception is inferior.h |
| 57 | (PC_IN_CALL_DUMMY) [ON_STACK]; see comments there. You cannot |
| 58 | assume that a frame address contains enough information to |
| 59 | reconstruct the frame; if you want more than just to identify the |
| 60 | frame (e.g. be able to fetch variables relative to that frame), |
| 61 | then save the whole struct frame_info (and the next struct |
| 62 | frame_info, since the latter is used for fetching variables on some |
| 63 | machines). */ |
| 64 | |
| 65 | #define FRAME_FP(fr) ((fr)->frame) |
| 66 | |
| 67 | /* We keep a cache of stack frames, each of which is a "struct |
| 68 | frame_info". The innermost one gets allocated (in |
| 69 | wait_for_inferior) each time the inferior stops; current_frame |
| 70 | points to it. Additional frames get allocated (in |
| 71 | get_prev_frame_info) as needed, and are chained through the next |
| 72 | and prev fields. Any time that the frame cache becomes invalid |
| 73 | (most notably when we execute something, but also if we change how |
| 74 | we interpret the frames (e.g. "set heuristic-fence-post" in |
| 75 | mips-tdep.c, or anything which reads new symbols)), we should call |
| 76 | reinit_frame_cache. */ |
| 77 | |
| 78 | struct frame_info |
| 79 | { |
| 80 | /* Nominal address of the frame described. See comments at FRAME_FP |
| 81 | about what this means outside the *FRAME* macros; in the *FRAME* |
| 82 | macros, it can mean whatever makes most sense for this machine. */ |
| 83 | FRAME_ADDR frame; |
| 84 | |
| 85 | /* Address at which execution is occurring in this frame. |
| 86 | For the innermost frame, it's the current pc. |
| 87 | For other frames, it is a pc saved in the next frame. */ |
| 88 | CORE_ADDR pc; |
| 89 | |
| 90 | /* Nonzero if this is a frame associated with calling a signal handler. |
| 91 | |
| 92 | Set by machine-dependent code. On some machines, if |
| 93 | the machine-dependent code fails to check for this, the backtrace |
| 94 | will look relatively normal. For example, on the i386 |
| 95 | #3 0x158728 in sighold () |
| 96 | On other machines (e.g. rs6000), the machine-dependent code better |
| 97 | set this to prevent us from trying to print it like a normal frame. */ |
| 98 | int signal_handler_caller; |
| 99 | |
| 100 | /* Anything extra for this structure that may have been defined |
| 101 | in the machine dependent files. */ |
| 102 | #ifdef EXTRA_FRAME_INFO |
| 103 | EXTRA_FRAME_INFO |
| 104 | #endif |
| 105 | |
| 106 | /* We should probably also store a "struct frame_saved_regs" here. |
| 107 | This is already done by some machines (e.g. config/m88k/tm-m88k.h) |
| 108 | but there is no reason it couldn't be general. */ |
| 109 | |
| 110 | /* Pointers to the next and previous frame_info's in the frame cache. */ |
| 111 | FRAME next, prev; |
| 112 | }; |
| 113 | |
| 114 | /* Describe the saved registers of a frame. */ |
| 115 | |
| 116 | struct frame_saved_regs |
| 117 | { |
| 118 | |
| 119 | /* For each register, address of where it was saved on entry to |
| 120 | the frame, or zero if it was not saved on entry to this frame. |
| 121 | This includes special registers such as pc and fp saved in |
| 122 | special ways in the stack frame. The SP_REGNUM is even more |
| 123 | special, the address here is the sp for the next frame, not the |
| 124 | address where the sp was saved. */ |
| 125 | |
| 126 | CORE_ADDR regs[NUM_REGS]; |
| 127 | }; |
| 128 | |
| 129 | /* Define a default FRAME_CHAIN_VALID, in the form that is suitable for most |
| 130 | targets. If FRAME_CHAIN_VALID returns zero it means that the given frame |
| 131 | is the outermost one and has no caller. |
| 132 | |
| 133 | If a particular target needs a different definition, then it can override |
| 134 | the definition here by providing one in the tm file. */ |
| 135 | |
| 136 | #if !defined (FRAME_CHAIN_VALID) |
| 137 | |
| 138 | #if defined (FRAME_CHAIN_VALID_ALTERNATE) |
| 139 | |
| 140 | /* Use the alternate method of avoiding running up off the end of the frame |
| 141 | chain or following frames back into the startup code. See the comments |
| 142 | in objfiles.h. */ |
| 143 | |
| 144 | #define FRAME_CHAIN_VALID(chain, thisframe) \ |
| 145 | ((chain) != 0 \ |
| 146 | && !inside_main_func ((thisframe) -> pc) \ |
| 147 | && !inside_entry_func ((thisframe) -> pc)) |
| 148 | |
| 149 | #else |
| 150 | |
| 151 | #define FRAME_CHAIN_VALID(chain, thisframe) \ |
| 152 | ((chain) != 0 \ |
| 153 | && !inside_entry_file (FRAME_SAVED_PC (thisframe))) |
| 154 | |
| 155 | #endif /* FRAME_CHAIN_VALID_ALTERNATE */ |
| 156 | |
| 157 | #endif /* FRAME_CHAIN_VALID */ |
| 158 | |
| 159 | /* If we encounter a request to use base register addressing of variables |
| 160 | on a machine for which gdb has not been configured to support such |
| 161 | access, report the failure to support this access mode. */ |
| 162 | |
| 163 | /* FIXME: Code using this should be using get_saved_register, and a |
| 164 | basereg number should just be an ordinary register number. There |
| 165 | is no reason for this to be machine-specific. */ |
| 166 | |
| 167 | #if !defined (FRAME_GET_BASEREG_VALUE) |
| 168 | |
| 169 | #define FRAME_GET_BASEREG_VALUE(frame, regno) \ |
| 170 | (error ("Missing valid method for finding contents of base register."),0) |
| 171 | |
| 172 | #endif |
| 173 | |
| 174 | /* The stack frame that the user has specified for commands to act on. |
| 175 | Note that one cannot assume this is the address of valid data. */ |
| 176 | |
| 177 | extern FRAME selected_frame; |
| 178 | |
| 179 | /* Level of the selected frame: |
| 180 | 0 for innermost, 1 for its caller, ... |
| 181 | or -1 for frame specified by address with no defined level. */ |
| 182 | |
| 183 | extern int selected_frame_level; |
| 184 | |
| 185 | extern struct frame_info * |
| 186 | get_prev_frame_info PARAMS ((FRAME)); |
| 187 | |
| 188 | extern FRAME |
| 189 | create_new_frame PARAMS ((FRAME_ADDR, CORE_ADDR)); |
| 190 | |
| 191 | extern void |
| 192 | flush_cached_frames PARAMS ((void)); |
| 193 | |
| 194 | extern void |
| 195 | reinit_frame_cache PARAMS ((void)); |
| 196 | |
| 197 | extern void |
| 198 | get_frame_saved_regs PARAMS ((struct frame_info *, struct frame_saved_regs *)); |
| 199 | |
| 200 | extern void |
| 201 | set_current_frame PARAMS ((FRAME)); |
| 202 | |
| 203 | extern FRAME |
| 204 | get_prev_frame PARAMS ((FRAME)); |
| 205 | |
| 206 | extern FRAME |
| 207 | get_current_frame PARAMS ((void)); |
| 208 | |
| 209 | extern FRAME |
| 210 | get_next_frame PARAMS ((FRAME)); |
| 211 | |
| 212 | extern struct block * |
| 213 | get_frame_block PARAMS ((FRAME)); |
| 214 | |
| 215 | extern struct block * |
| 216 | get_current_block PARAMS ((void)); |
| 217 | |
| 218 | extern struct block * |
| 219 | get_selected_block PARAMS ((void)); |
| 220 | |
| 221 | extern struct symbol * |
| 222 | get_frame_function PARAMS ((FRAME)); |
| 223 | |
| 224 | extern CORE_ADDR |
| 225 | get_frame_pc PARAMS ((FRAME)); |
| 226 | |
| 227 | extern CORE_ADDR |
| 228 | get_pc_function_start PARAMS ((CORE_ADDR)); |
| 229 | |
| 230 | extern struct block * block_for_pc PARAMS ((CORE_ADDR)); |
| 231 | |
| 232 | extern int frameless_look_for_prologue PARAMS ((FRAME)); |
| 233 | |
| 234 | extern void print_frame_args PARAMS ((struct symbol *, struct frame_info *, |
| 235 | int, FILE *)); |
| 236 | |
| 237 | extern FRAME find_relative_frame PARAMS ((FRAME, int*)); |
| 238 | |
| 239 | extern void print_stack_frame PARAMS ((FRAME, int, int)); |
| 240 | |
| 241 | extern void select_frame PARAMS ((FRAME, int)); |
| 242 | |
| 243 | extern void record_selected_frame PARAMS ((FRAME_ADDR *, int *)); |
| 244 | |
| 245 | extern void print_frame_info PARAMS ((struct frame_info *, int, int, int)); |
| 246 | |
| 247 | extern CORE_ADDR find_saved_register PARAMS ((FRAME, int)); |
| 248 | |
| 249 | extern FRAME block_innermost_frame PARAMS ((struct block *)); |
| 250 | |
| 251 | extern CORE_ADDR sigtramp_saved_pc PARAMS ((FRAME)); |
| 252 | |
| 253 | #endif /* !defined (FRAME_H) */ |