gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2
   3    Copyright 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996,
   4    1997, 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #if !defined (FRAME_H)
  24 #define FRAME_H 1
  25
  26 /* Describe the saved registers of a frame.  */
  27
  28 #if defined (EXTRA_FRAME_INFO) || defined (FRAME_FIND_SAVED_REGS)
  29 /* XXXX - deprecated */
  30 struct frame_saved_regs
  31   {
  32     /* For each register R (except the SP), regs[R] is the address at
  33        which it was saved on entry to the frame, or zero if it was not
  34        saved on entry to this frame.  This includes special registers
  35        such as pc and fp saved in special ways in the stack frame.
  36
  37        regs[SP_REGNUM] is different.  It holds the actual SP, not the
  38        address at which it was saved.  */
  39
  40     CORE_ADDR regs[NUM_REGS];
  41   };
  42 #endif
  43
  44 /* We keep a cache of stack frames, each of which is a "struct
  45    frame_info".  The innermost one gets allocated (in
  46    wait_for_inferior) each time the inferior stops; current_frame
  47    points to it.  Additional frames get allocated (in
  48    get_prev_frame) as needed, and are chained through the next
  49    and prev fields.  Any time that the frame cache becomes invalid
  50    (most notably when we execute something, but also if we change how
  51    we interpret the frames (e.g. "set heuristic-fence-post" in
  52    mips-tdep.c, or anything which reads new symbols)), we should call
  53    reinit_frame_cache.  */
  54
  55 struct frame_info
  56   {
  57     /* Nominal address of the frame described.  See comments at FRAME_FP
  58        about what this means outside the *FRAME* macros; in the *FRAME*
  59        macros, it can mean whatever makes most sense for this machine.  */
  60     CORE_ADDR frame;
  61
  62     /* Address at which execution is occurring in this frame.
  63        For the innermost frame, it's the current pc.
  64        For other frames, it is a pc saved in the next frame.  */
  65     CORE_ADDR pc;
  66
  67     /* Level of this frame.  The inner-most (youngest) frame is at
  68        level 0.  As you move towards the outer-most (oldest) frame,
  69        the level increases.  This is a cached value.  It could just as
  70        easily be computed by counting back from the selected frame to
  71        the inner most frame.  */
  72     /* NOTE: cagney/2002-04-05: Perhaphs a level of ``-1'' should be
  73        reserved to indicate a bogus frame - one that has been created
  74        just to keep GDB happy (GDB always needs a frame).  For the
  75        moment leave this as speculation.  */
  76     int level;
  77
  78     /* Nonzero if this is a frame associated with calling a signal handler.
  79
  80        Set by machine-dependent code.  On some machines, if
  81        the machine-dependent code fails to check for this, the backtrace
  82        will look relatively normal.  For example, on the i386
  83        #3  0x158728 in sighold ()
  84        On other machines (e.g. rs6000), the machine-dependent code better
  85        set this to prevent us from trying to print it like a normal frame.  */
  86     int signal_handler_caller;
  87
  88     /* For each register, address of where it was saved on entry to
  89        the frame, or zero if it was not saved on entry to this frame.
  90        This includes special registers such as pc and fp saved in
  91        special ways in the stack frame.  The SP_REGNUM is even more
  92        special, the address here is the sp for the previous frame, not
  93        the address where the sp was saved.  */
  94     /* Allocated by frame_saved_regs_zalloc () which is called /
  95        initialized by FRAME_INIT_SAVED_REGS(). */
  96     CORE_ADDR *saved_regs;      /*NUM_REGS + NUM_PSEUDO_REGS*/
  97
  98 #ifdef EXTRA_FRAME_INFO
  99     /* XXXX - deprecated */
 100     /* Anything extra for this structure that may have been defined
 101        in the machine dependent files. */
 102       EXTRA_FRAME_INFO
 103 #endif
 104
 105     /* Anything extra for this structure that may have been defined
 106        in the machine dependent files. */
 107     /* Allocated by frame_obstack_alloc () which is called /
 108        initialized by INIT_EXTRA_FRAME_INFO */
 109     struct frame_extra_info *extra_info;
 110
 111     /* If dwarf2 unwind frame informations is used, this structure holds all
 112        related unwind data.  */
 113     struct unwind_contect *context;
 114
 115     /* Pointers to the next (down, inner) and previous (up, outer)
 116        frame_info's in the frame cache.  */
 117     struct frame_info *next; /* down, inner */
 118     struct frame_info *prev; /* up, outer */
 119   };
 120
 121 /* Values for the source flag to be used in print_frame_info_base(). */
 122 enum print_what
 123   {
 124     /* Print only the source line, like in stepi. */
 125     SRC_LINE = -1,
 126     /* Print only the location, i.e. level, address (sometimes)
 127        function, args, file, line, line num. */
 128     LOCATION,
 129     /* Print both of the above. */
 130     SRC_AND_LOC,
 131     /* Print location only, but always include the address. */
 132     LOC_AND_ADDRESS
 133   };
 134
 135 /* Allocate additional space for appendices to a struct frame_info.
 136    NOTE: Much of GDB's code works on the assumption that the allocated
 137    saved_regs[] array is the size specified below.  If you try to make
 138    that array smaller, GDB will happily walk off its end. */
 139
 140 #ifdef SIZEOF_FRAME_SAVED_REGS
 141 #error "SIZEOF_FRAME_SAVED_REGS can not be re-defined"
 142 #endif
 143 #define SIZEOF_FRAME_SAVED_REGS \
 144         (sizeof (CORE_ADDR) * (NUM_REGS+NUM_PSEUDO_REGS))
 145
 146 extern void *frame_obstack_alloc (unsigned long size);
 147 extern void frame_saved_regs_zalloc (struct frame_info *);
 148
 149 /* Return the frame address from FI.  Except in the machine-dependent
 150    *FRAME* macros, a frame address has no defined meaning other than
 151    as a magic cookie which identifies a frame over calls to the
 152    inferior.  The only known exception is inferior.h
 153    (PC_IN_CALL_DUMMY) [ON_STACK]; see comments there.  You cannot
 154    assume that a frame address contains enough information to
 155    reconstruct the frame; if you want more than just to identify the
 156    frame (e.g. be able to fetch variables relative to that frame),
 157    then save the whole struct frame_info (and the next struct
 158    frame_info, since the latter is used for fetching variables on some
 159    machines).  */
 160
 161 #define FRAME_FP(fi) ((fi)->frame)
 162
 163 /* Define a default FRAME_CHAIN_VALID, in the form that is suitable for most
 164    targets.  If FRAME_CHAIN_VALID returns zero it means that the given frame
 165    is the outermost one and has no caller.
 166
 167    XXXX - both default and alternate frame_chain_valid functions are
 168    deprecated.  New code should use dummy frames and one of the
 169    generic functions. */
 170
 171 extern int file_frame_chain_valid (CORE_ADDR, struct frame_info *);
 172 extern int func_frame_chain_valid (CORE_ADDR, struct frame_info *);
 173 extern int nonnull_frame_chain_valid (CORE_ADDR, struct frame_info *);
 174 extern int generic_file_frame_chain_valid (CORE_ADDR, struct frame_info *);
 175 extern int generic_func_frame_chain_valid (CORE_ADDR, struct frame_info *);
 176 extern void generic_save_dummy_frame_tos (CORE_ADDR sp);
 177
 178 /* The stack frame that the user has specified for commands to act on.
 179    Note that one cannot assume this is the address of valid data.  */
 180
 181 extern struct frame_info *selected_frame;
 182
 183 /* Level of the selected frame:
 184    0 for innermost, 1 for its caller, ...
 185    or -1 for frame specified by address with no defined level.  */
 186
 187 extern int selected_frame_level;
 188
 189 extern struct frame_info *create_new_frame (CORE_ADDR, CORE_ADDR);
 190
 191 extern void flush_cached_frames (void);
 192
 193 extern void reinit_frame_cache (void);
 194
 195
 196 #ifdef FRAME_FIND_SAVED_REGS
 197 /* XXX - deprecated */
 198 #define FRAME_INIT_SAVED_REGS(FI) get_frame_saved_regs (FI, NULL)
 199 extern void get_frame_saved_regs (struct frame_info *,
 200                                   struct frame_saved_regs *);
 201 #endif
 202
 203 extern void set_current_frame (struct frame_info *);
 204
 205 extern struct frame_info *get_prev_frame (struct frame_info *);
 206
 207 extern struct frame_info *get_current_frame (void);
 208
 209 extern struct frame_info *get_next_frame (struct frame_info *);
 210
 211 extern struct block *get_frame_block (struct frame_info *,
 212                                       CORE_ADDR *addr_in_block);
 213
 214 extern struct block *get_current_block (CORE_ADDR *addr_in_block);
 215
 216 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 217
 218 extern struct symbol *get_frame_function (struct frame_info *);
 219
 220 extern CORE_ADDR get_frame_pc (struct frame_info *);
 221
 222 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 223
 224 extern struct block *block_for_pc (CORE_ADDR);
 225
 226 extern struct block *block_for_pc_sect (CORE_ADDR, asection *);
 227
 228 extern int frameless_look_for_prologue (struct frame_info *);
 229
 230 extern void print_frame_args (struct symbol *, struct frame_info *,
 231                               int, struct ui_file *);
 232
 233 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 234
 235 extern void show_and_print_stack_frame (struct frame_info *fi, int level,
 236                                         int source);
 237
 238 extern void print_stack_frame (struct frame_info *, int, int);
 239
 240 extern void print_only_stack_frame (struct frame_info *, int, int);
 241
 242 extern void show_stack_frame (struct frame_info *);
 243
 244 extern void select_frame (struct frame_info *, int);
 245
 246 extern void record_selected_frame (CORE_ADDR *, int *);
 247
 248 extern void select_and_print_frame (struct frame_info *, int);
 249
 250 extern void print_frame_info (struct frame_info *, int, int, int);
 251
 252 extern void show_frame_info (struct frame_info *, int, int, int);
 253
 254 extern CORE_ADDR find_saved_register (struct frame_info *, int);
 255
 256 extern struct frame_info *block_innermost_frame (struct block *);
 257
 258 extern struct frame_info *find_frame_addr_in_frame_chain (CORE_ADDR);
 259
 260 extern CORE_ADDR sigtramp_saved_pc (struct frame_info *);
 261
 262 extern CORE_ADDR generic_read_register_dummy (CORE_ADDR pc,
 263                                               CORE_ADDR fp, int);
 264 extern void generic_push_dummy_frame (void);
 265 extern void generic_pop_current_frame (void (*)(struct frame_info *));
 266 extern void generic_pop_dummy_frame (void);
 267
 268 extern int generic_pc_in_call_dummy (CORE_ADDR pc,
 269                                      CORE_ADDR sp, CORE_ADDR fp);
 270 extern char *generic_find_dummy_frame (CORE_ADDR pc, CORE_ADDR fp);
 271
 272 extern void generic_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun,
 273                                     int nargs, struct value **args,
 274                                     struct type *type, int gcc_p);
 275
 276 extern void generic_get_saved_register (char *, int *, CORE_ADDR *,
 277                                         struct frame_info *, int,
 278                                         enum lval_type *);
 279
 280 extern void get_saved_register (char *raw_buffer, int *optimized,
 281                                 CORE_ADDR * addrp,
 282                                 struct frame_info *frame,
 283                                 int regnum, enum lval_type *lval);
 284
 285 #endif /* !defined (FRAME_H)  */