gdb/trad-frame.h

   1 /* Traditional frame unwind support, for GDB the GNU Debugger.
   2
   3    Copyright 2003 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 #ifndef TRAD_FRAME_H
  23 #define TRAD_FRAME_H
  24
  25 struct frame_info;
  26
  27 /* A traditional saved regs table, indexed by REGNUM, encoding where
  28    the value of REGNUM for the previous frame can be found in this
  29    frame.
  30
  31    The table is initialized with an identity encoding (ADDR == -1,
  32    REALREG == REGNUM) indicating that the value of REGNUM in the
  33    previous frame can be found in register REGNUM (== REALREG) in this
  34    frame.
  35
  36    The initial encoding can then be changed:
  37
  38    Modify ADDR (REALREG >= 0, ADDR != -1) to indicate that the value
  39    of register REGNUM in the previous frame can be found in memory at
  40    ADDR in this frame (addr_p, !realreg_p, !value_p).
  41
  42    Modify REALREG (REALREG >= 0, ADDR == -1) to indicate that the
  43    value of register REGNUM in the previous frame is found in register
  44    REALREG in this frame (!addr_p, realreg_p, !value_p).
  45
  46    Call trad_frame_set_value (REALREG == -1) to indicate that the
  47    value of register REGNUM in the previous frame is found in ADDR
  48    (!addr_p, !realreg_p, value_p).
  49
  50    Call trad_frame_set_unknown (REALREG == -2) to indicate that the
  51    register's value is not known.  */
  52
  53 struct trad_frame_saved_reg
  54 {
  55   LONGEST addr; /* A CORE_ADDR fits in a longest.  */
  56   int realreg;
  57 };
  58
  59 /* Encode REGNUM value in the trad-frame.  */
  60 void trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
  61                            int regnum, LONGEST val);
  62
  63 /* Mark REGNUM as unknown.  */
  64 void trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
  65                              int regnum);
  66
  67 /* Convenience functions, return non-zero if the register has been
  68    encoded as specified.  */
  69 int trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[],
  70                         int regnum);
  71 int trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[],
  72                        int regnum);
  73 int trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
  74                           int regnum);
  75
  76
  77 /* Return a freshly allocated (and initialized) trad_frame array.  */
  78 struct trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct frame_info *next_frame);
  79
  80 /* Given the trad_frame info, return the location of the specified
  81    register.  */
  82 void trad_frame_prev_register (struct frame_info *next_frame,
  83                                struct trad_frame_saved_reg this_saved_regs[],
  84                                int regnum, int *optimizedp,
  85                                enum lval_type *lvalp, CORE_ADDR *addrp,
  86                                int *realregp, void *bufferp);
  87
  88 #endif