gdb/frame.h

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