gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2    Copyright 1986, 1989, 1991, 1992, 1999 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #if !defined (FRAME_H)
  21 #define FRAME_H 1
  22
  23 /* Describe the saved registers of a frame.  */
  24
  25 #if defined (EXTRA_FRAME_INFO) || defined (FRAME_FIND_SAVED_REGS)
  26 /* XXXX - deprecated */
  27 struct frame_saved_regs
  28   {
  29
  30     /* For each register, address of where it was saved on entry to
  31        the frame, or zero if it was not saved on entry to this frame.
  32        This includes special registers such as pc and fp saved in
  33        special ways in the stack frame.  The SP_REGNUM is even more
  34        special, the address here is the sp for the next frame, not the
  35        address where the sp was saved.  */
  36
  37     CORE_ADDR regs[NUM_REGS];
  38   };
  39 #endif
  40
  41 /* We keep a cache of stack frames, each of which is a "struct
  42    frame_info".  The innermost one gets allocated (in
  43    wait_for_inferior) each time the inferior stops; current_frame
  44    points to it.  Additional frames get allocated (in
  45    get_prev_frame_info) as needed, and are chained through the next
  46    and prev fields.  Any time that the frame cache becomes invalid
  47    (most notably when we execute something, but also if we change how
  48    we interpret the frames (e.g. "set heuristic-fence-post" in
  49    mips-tdep.c, or anything which reads new symbols)), we should call
  50    reinit_frame_cache.  */
  51
  52 struct frame_info
  53   {
  54     /* Nominal address of the frame described.  See comments at FRAME_FP
  55        about what this means outside the *FRAME* macros; in the *FRAME*
  56        macros, it can mean whatever makes most sense for this machine.  */
  57     CORE_ADDR frame;
  58
  59     /* Address at which execution is occurring in this frame.
  60        For the innermost frame, it's the current pc.
  61        For other frames, it is a pc saved in the next frame.  */
  62     CORE_ADDR pc;
  63
  64     /* Nonzero if this is a frame associated with calling a signal handler.
  65
  66        Set by machine-dependent code.  On some machines, if
  67        the machine-dependent code fails to check for this, the backtrace
  68        will look relatively normal.  For example, on the i386
  69          #3  0x158728 in sighold ()
  70        On other machines (e.g. rs6000), the machine-dependent code better
  71        set this to prevent us from trying to print it like a normal frame.  */
  72     int signal_handler_caller;
  73
  74     /* For each register, address of where it was saved on entry to
  75        the frame, or zero if it was not saved on entry to this frame.
  76        This includes special registers such as pc and fp saved in
  77        special ways in the stack frame.  The SP_REGNUM is even more
  78        special, the address here is the sp for the next frame, not the
  79        address where the sp was saved.  */
  80     /* Allocated by frame_saved_regs_zalloc () which is called /
  81        initialized by FRAME_INIT_SAVED_REGS(). */
  82     CORE_ADDR *saved_regs; /*NUM_REGS*/
  83
  84 #ifdef EXTRA_FRAME_INFO
  85     /* XXXX - deprecated */
  86     /* Anything extra for this structure that may have been defined
  87        in the machine dependent files. */
  88     EXTRA_FRAME_INFO
  89 #endif
  90
  91     /* Anything extra for this structure that may have been defined
  92        in the machine dependent files. */
  93     /* Allocated by frame_obstack_alloc () which is called /
  94        initialized by INIT_EXTRA_FRAME_INFO */
  95     struct frame_extra_info *extra_info;
  96
  97     /* Pointers to the next and previous frame_info's in the frame cache.  */
  98    struct frame_info *next, *prev;
  99   };
 100
 101 /* Allocate additional space for appendices to a struct frame_info. */
 102
 103 #ifndef SIZEOF_FRAME_SAVED_REGS
 104 #define SIZEOF_FRAME_SAVED_REGS (sizeof (CORE_ADDR) * (NUM_REGS))
 105 #endif
 106 extern void *frame_obstack_alloc PARAMS ((unsigned long size));
 107 extern void frame_saved_regs_zalloc PARAMS ((struct frame_info *));
 108
 109 /* Dummy frame.  This saves the processor state just prior to setting up the
 110    inferior function call.  On most targets, the registers are saved on the
 111    target stack, but that really slows down function calls.  */
 112
 113 struct dummy_frame
 114 {
 115   struct dummy_frame *next;
 116
 117   CORE_ADDR pc;
 118   CORE_ADDR fp;
 119   CORE_ADDR sp;
 120   char regs[REGISTER_BYTES];
 121 };
 122
 123 /* Return the frame address from FR.  Except in the machine-dependent
 124    *FRAME* macros, a frame address has no defined meaning other than
 125    as a magic cookie which identifies a frame over calls to the
 126    inferior.  The only known exception is inferior.h
 127    (PC_IN_CALL_DUMMY) [ON_STACK]; see comments there.  You cannot
 128    assume that a frame address contains enough information to
 129    reconstruct the frame; if you want more than just to identify the
 130    frame (e.g. be able to fetch variables relative to that frame),
 131    then save the whole struct frame_info (and the next struct
 132    frame_info, since the latter is used for fetching variables on some
 133    machines).  */
 134
 135 #define FRAME_FP(fi) ((fi)->frame)
 136
 137 /* Define a default FRAME_CHAIN_VALID, in the form that is suitable for most
 138    targets.  If FRAME_CHAIN_VALID returns zero it means that the given frame
 139    is the outermost one and has no caller.
 140
 141    If a particular target needs a different definition, then it can override
 142    the definition here by providing one in the tm file.
 143
 144    XXXX - both default and alternate frame_chain_valid functions are
 145    deprecated.  New code should use generic dummy frames. */
 146
 147 extern int default_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 148 extern int alternate_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 149 extern int nonnull_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 150 extern int generic_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 151
 152 #if !defined (FRAME_CHAIN_VALID)
 153 #if !defined (FRAME_CHAIN_VALID_ALTERNATE)
 154 #define FRAME_CHAIN_VALID(chain, thisframe) default_frame_chain_valid (chain, thisframe)
 155 #else
 156 /* Use the alternate method of avoiding running up off the end of the frame
 157    chain or following frames back into the startup code.  See the comments
 158    in objfiles.h. */
 159 #define FRAME_CHAIN_VALID(chain, thisframe) alternate_frame_chain_valid (chain,thisframe)
 160 #endif  /* FRAME_CHAIN_VALID_ALTERNATE */
 161 #endif  /* FRAME_CHAIN_VALID */
 162
 163 /* The stack frame that the user has specified for commands to act on.
 164    Note that one cannot assume this is the address of valid data.  */
 165
 166 extern struct frame_info *selected_frame;
 167
 168 /* Level of the selected frame:
 169    0 for innermost, 1 for its caller, ...
 170    or -1 for frame specified by address with no defined level.  */
 171
 172 extern int selected_frame_level;
 173
 174 extern struct frame_info *get_prev_frame_info PARAMS ((struct frame_info *));
 175
 176 extern struct frame_info *create_new_frame PARAMS ((CORE_ADDR, CORE_ADDR));
 177
 178 extern void flush_cached_frames PARAMS ((void));
 179
 180 extern void reinit_frame_cache PARAMS ((void));
 181
 182
 183 #ifdef FRAME_FIND_SAVED_REGS
 184 /* XXX - deprecated */
 185 #define FRAME_INIT_SAVED_REGS(FI) get_frame_saved_regs (FI, NULL)
 186 extern void get_frame_saved_regs PARAMS ((struct frame_info *,
 187                                           struct frame_saved_regs *));
 188 #endif
 189
 190 extern void set_current_frame PARAMS ((struct frame_info *));
 191
 192 extern struct frame_info *get_prev_frame PARAMS ((struct frame_info *));
 193
 194 extern struct frame_info *get_current_frame PARAMS ((void));
 195
 196 extern struct frame_info *get_next_frame PARAMS ((struct frame_info *));
 197
 198 extern struct block *get_frame_block PARAMS ((struct frame_info *));
 199
 200 extern struct block *get_current_block PARAMS ((void));
 201
 202 extern struct block *get_selected_block PARAMS ((void));
 203
 204 extern struct symbol *get_frame_function PARAMS ((struct frame_info *));
 205
 206 extern CORE_ADDR get_frame_pc PARAMS ((struct frame_info *));
 207
 208 extern CORE_ADDR get_pc_function_start PARAMS ((CORE_ADDR));
 209
 210 extern struct block * block_for_pc PARAMS ((CORE_ADDR));
 211
 212 extern struct block * block_for_pc_sect PARAMS ((CORE_ADDR, asection *));
 213
 214 extern int frameless_look_for_prologue PARAMS ((struct frame_info *));
 215
 216 extern void print_frame_args PARAMS ((struct symbol *, struct frame_info *,
 217                                       int, GDB_FILE *));
 218
 219 extern struct frame_info *find_relative_frame PARAMS ((struct frame_info *, int*));
 220
 221 extern void print_stack_frame PARAMS ((struct frame_info *, int, int));
 222
 223 extern void print_only_stack_frame PARAMS ((struct frame_info *, int, int));
 224
 225 extern void show_stack_frame PARAMS ((struct frame_info *));
 226
 227 extern void select_frame PARAMS ((struct frame_info *, int));
 228
 229 extern void record_selected_frame PARAMS ((CORE_ADDR *, int *));
 230
 231 extern void select_and_print_frame PARAMS ((struct frame_info *, int));
 232
 233 extern void print_frame_info PARAMS ((struct frame_info *, int, int, int));
 234
 235 extern void show_frame_info PARAMS ((struct frame_info *, int, int, int));
 236
 237 extern CORE_ADDR find_saved_register PARAMS ((struct frame_info *, int));
 238
 239 extern struct frame_info *block_innermost_frame PARAMS ((struct block *));
 240
 241 extern struct frame_info *find_frame_addr_in_frame_chain PARAMS ((CORE_ADDR));
 242
 243 extern CORE_ADDR sigtramp_saved_pc PARAMS ((struct frame_info *));
 244
 245 extern CORE_ADDR generic_read_register_dummy PARAMS ((CORE_ADDR pc,
 246                                                       CORE_ADDR fp,
 247                                                       int));
 248 extern void      generic_push_dummy_frame    PARAMS ((void));
 249 extern void      generic_pop_current_frame   PARAMS ((void (*) (struct frame_info *)));
 250 extern void      generic_pop_dummy_frame     PARAMS ((void));
 251
 252 extern int       generic_pc_in_call_dummy    PARAMS ((CORE_ADDR pc,
 253                                                       CORE_ADDR fp));
 254 extern char *    generic_find_dummy_frame    PARAMS ((CORE_ADDR pc,
 255                                                       CORE_ADDR fp));
 256
 257 #ifdef __GNUC__
 258 /* Some native compilers, even ones that are supposed to be ANSI and for which __STDC__
 259    is true, complain about forward decls of enums. */
 260 enum lval_type;
 261 extern void      generic_get_saved_register  PARAMS ((char *, int *, CORE_ADDR *, struct frame_info *, int, enum lval_type *));
 262 #endif
 263
 264 #endif /* !defined (FRAME_H)  */