gdb/frame.h

   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., 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 struct frame_saved_regs
  26   {
  27
  28     /* For each register, address of where it was saved on entry to
  29        the frame, or zero if it was not saved on entry to this frame.
  30        This includes special registers such as pc and fp saved in
  31        special ways in the stack frame.  The SP_REGNUM is even more
  32        special, the address here is the sp for the next frame, not the
  33        address where the sp was saved.  */
  34
  35     CORE_ADDR regs[NUM_REGS];
  36   };
  37
  38 /* We keep a cache of stack frames, each of which is a "struct
  39    frame_info".  The innermost one gets allocated (in
  40    wait_for_inferior) each time the inferior stops; current_frame
  41    points to it.  Additional frames get allocated (in
  42    get_prev_frame_info) as needed, and are chained through the next
  43    and prev fields.  Any time that the frame cache becomes invalid
  44    (most notably when we execute something, but also if we change how
  45    we interpret the frames (e.g. "set heuristic-fence-post" in
  46    mips-tdep.c, or anything which reads new symbols)), we should call
  47    reinit_frame_cache.  */
  48
  49 struct frame_info
  50   {
  51     /* Nominal address of the frame described.  See comments at FRAME_FP
  52        about what this means outside the *FRAME* macros; in the *FRAME*
  53        macros, it can mean whatever makes most sense for this machine.  */
  54     CORE_ADDR frame;
  55
  56     /* Address at which execution is occurring in this frame.
  57        For the innermost frame, it's the current pc.
  58        For other frames, it is a pc saved in the next frame.  */
  59     CORE_ADDR pc;
  60
  61     /* Nonzero if this is a frame associated with calling a signal handler.
  62
  63        Set by machine-dependent code.  On some machines, if
  64        the machine-dependent code fails to check for this, the backtrace
  65        will look relatively normal.  For example, on the i386
  66          #3  0x158728 in sighold ()
  67        On other machines (e.g. rs6000), the machine-dependent code better
  68        set this to prevent us from trying to print it like a normal frame.  */
  69     int signal_handler_caller;
  70
  71     /* Anything extra for this structure that may have been defined
  72        in the machine dependent files. */
  73 #ifdef EXTRA_FRAME_INFO
  74     EXTRA_FRAME_INFO
  75 #endif
  76
  77     /* We should probably also store a "struct frame_saved_regs" here.
  78        This is already done by some machines (e.g. config/m88k/tm-m88k.h)
  79        but there is no reason it couldn't be general.  */
  80
  81     /* Pointers to the next and previous frame_info's in the frame cache.  */
  82    struct frame_info *next, *prev;
  83   };
  84
  85 /* Dummy frame.  This saves the processor state just prior to setting up the
  86    inferior function call.  On most targets, the registers are saved on the
  87    target stack, but that really slows down function calls.  */
  88
  89 struct dummy_frame
  90 {
  91   struct dummy_frame *next;
  92
  93   CORE_ADDR pc;
  94   CORE_ADDR fp;
  95   CORE_ADDR sp;
  96   char regs[REGISTER_BYTES];
  97 };
  98
  99 /* Return the frame address from FR.  Except in the machine-dependent
 100    *FRAME* macros, a frame address has no defined meaning other than
 101    as a magic cookie which identifies a frame over calls to the
 102    inferior.  The only known exception is inferior.h
 103    (PC_IN_CALL_DUMMY) [ON_STACK]; see comments there.  You cannot
 104    assume that a frame address contains enough information to
 105    reconstruct the frame; if you want more than just to identify the
 106    frame (e.g. be able to fetch variables relative to that frame),
 107    then save the whole struct frame_info (and the next struct
 108    frame_info, since the latter is used for fetching variables on some
 109    machines).  */
 110
 111 #define FRAME_FP(fi) ((fi)->frame)
 112
 113 /* Define a default FRAME_CHAIN_VALID, in the form that is suitable for most
 114    targets.  If FRAME_CHAIN_VALID returns zero it means that the given frame
 115    is the outermost one and has no caller.
 116
 117    If a particular target needs a different definition, then it can override
 118    the definition here by providing one in the tm file.
 119
 120    XXXX - both default and alternate frame_chain_valid functions are
 121    deprecated.  New code should use generic dummy frames. */
 122
 123 extern int default_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 124 extern int alternate_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 125 extern int nonnull_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 126 extern int generic_frame_chain_valid PARAMS ((CORE_ADDR, struct frame_info *));
 127
 128 #if !defined (FRAME_CHAIN_VALID)
 129 #if !defined (FRAME_CHAIN_VALID_ALTERNATE)
 130 #define FRAME_CHAIN_VALID(chain, thisframe) default_frame_chain_valid (chain, thisframe)
 131 #else
 132 /* Use the alternate method of avoiding running up off the end of the frame
 133    chain or following frames back into the startup code.  See the comments
 134    in objfiles.h. */
 135 #define FRAME_CHAIN_VALID(chain, thisframe) alternate_frame_chain_valid (chain,thisframe)
 136 #endif  /* FRAME_CHAIN_VALID_ALTERNATE */
 137 #endif  /* FRAME_CHAIN_VALID */
 138
 139 /* The stack frame that the user has specified for commands to act on.
 140    Note that one cannot assume this is the address of valid data.  */
 141
 142 extern struct frame_info *selected_frame;
 143
 144 /* Level of the selected frame:
 145    0 for innermost, 1 for its caller, ...
 146    or -1 for frame specified by address with no defined level.  */
 147
 148 extern int selected_frame_level;
 149
 150 extern struct frame_info *get_prev_frame_info PARAMS ((struct frame_info *));
 151
 152 extern struct frame_info *create_new_frame PARAMS ((CORE_ADDR, CORE_ADDR));
 153
 154 extern void flush_cached_frames PARAMS ((void));
 155
 156 extern void reinit_frame_cache PARAMS ((void));
 157
 158 extern void get_frame_saved_regs PARAMS ((struct frame_info *,
 159                                           struct frame_saved_regs *));
 160
 161 extern void set_current_frame PARAMS ((struct frame_info *));
 162
 163 extern struct frame_info *get_prev_frame PARAMS ((struct frame_info *));
 164
 165 extern struct frame_info *get_current_frame PARAMS ((void));
 166
 167 extern struct frame_info *get_next_frame PARAMS ((struct frame_info *));
 168
 169 extern struct block *get_frame_block PARAMS ((struct frame_info *));
 170
 171 extern struct block *get_current_block PARAMS ((void));
 172
 173 extern struct block *get_selected_block PARAMS ((void));
 174
 175 extern struct symbol *get_frame_function PARAMS ((struct frame_info *));
 176
 177 extern CORE_ADDR get_frame_pc PARAMS ((struct frame_info *));
 178
 179 extern CORE_ADDR get_pc_function_start PARAMS ((CORE_ADDR));
 180
 181 extern struct block * block_for_pc PARAMS ((CORE_ADDR));
 182
 183 extern struct block * block_for_pc_sect PARAMS ((CORE_ADDR, asection *));
 184
 185 extern int frameless_look_for_prologue PARAMS ((struct frame_info *));
 186
 187 extern void print_frame_args PARAMS ((struct symbol *, struct frame_info *,
 188                                       int, GDB_FILE *));
 189
 190 extern struct frame_info *find_relative_frame PARAMS ((struct frame_info *, int*));
 191
 192 extern void print_stack_frame PARAMS ((struct frame_info *, int, int));
 193
 194 extern void print_only_stack_frame PARAMS ((struct frame_info *, int, int));
 195
 196 extern void show_stack_frame PARAMS ((struct frame_info *));
 197
 198 extern void select_frame PARAMS ((struct frame_info *, int));
 199
 200 extern void record_selected_frame PARAMS ((CORE_ADDR *, int *));
 201
 202 extern void print_frame_info PARAMS ((struct frame_info *, int, int, int));
 203
 204 extern void show_frame_info PARAMS ((struct frame_info *, int, int, int));
 205
 206 extern CORE_ADDR find_saved_register PARAMS ((struct frame_info *, int));
 207
 208 extern struct frame_info *block_innermost_frame PARAMS ((struct block *));
 209
 210 extern struct frame_info *find_frame_addr_in_frame_chain PARAMS ((CORE_ADDR));
 211
 212 extern CORE_ADDR sigtramp_saved_pc PARAMS ((struct frame_info *));
 213
 214 extern CORE_ADDR generic_read_register_dummy PARAMS ((CORE_ADDR pc,
 215                                                       CORE_ADDR fp,
 216                                                       int));
 217 extern void      generic_push_dummy_frame    PARAMS ((void));
 218 extern void      generic_pop_current_frame   PARAMS ((void (*) (struct frame_info *)));
 219 extern void      generic_pop_dummy_frame     PARAMS ((void));
 220
 221 extern int       generic_pc_in_call_dummy    PARAMS ((CORE_ADDR pc,
 222                                                       CORE_ADDR fp));
 223 extern char *    generic_find_dummy_frame    PARAMS ((CORE_ADDR pc,
 224                                                       CORE_ADDR fp));
 225
 226 #ifdef __GNUC__
 227 /* Some native compilers, even ones that are supposed to be ANSI and for which __STDC__
 228    is true, complain about forward decls of enums. */
 229 enum lval_type;
 230 extern void      generic_get_saved_register  PARAMS ((char *, int *, CORE_ADDR *, struct frame_info *, int, enum lval_type *));
 231 #endif
 232
 233 #endif /* !defined (FRAME_H)  */