gcc/frame.h

   1 /* Header file for unwinding stack frames for exception handling.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1997, 1998 Free Software Foundation, Inc.
   4    Contributed by Jason Merrill <jason@cygnus.com>.
   5
   6 This file is part of GNU CC.
   7
   8 GNU CC 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, or (at your option)
  11 any later version.
  12
  13 GNU CC 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 GNU CC; see the file COPYING.  If not, write to
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.  */
  22
  23
  24 typedef struct frame_state
  25 {
  26   void *cfa;
  27   void *eh_ptr;
  28   long cfa_offset;
  29   long args_size;
  30   long reg_or_offset[FIRST_PSEUDO_REGISTER+1];
  31   unsigned short cfa_reg;
  32   unsigned short retaddr_column;
  33   char saved[FIRST_PSEUDO_REGISTER+1];
  34 } frame_state;
  35
  36 /* Values for 'saved' above.  */
  37 #define REG_UNSAVED 0
  38 #define REG_SAVED_OFFSET 1
  39 #define REG_SAVED_REG 2
  40
  41 /* The representation for an "object" to be searched for frame unwind info.
  42    For targets with named sections, one object is an executable or shared
  43    library; for other targets, one object is one translation unit.
  44
  45    A copy of this structure declaration is printed by collect2.c;
  46    keep the copies synchronized!  */
  47
  48 struct object {
  49   void *pc_begin;
  50   void *pc_end;
  51   struct dwarf_fde *fde_begin;
  52   struct dwarf_fde **fde_array;
  53   size_t count;
  54   struct object *next;
  55 };
  56
  57 /* Note the following routines are exported interfaces from libgcc; do not
  58    change these interfaces.  Instead create new interfaces.  Also note
  59    references to these functions may be made weak in files where they
  60    are referenced.  */
  61
  62 extern void __register_frame (void * );
  63 extern void __register_frame_table (void *);
  64 extern void __deregister_frame (void *);
  65
  66 /* Called either from crtbegin.o or a static constructor to register the
  67    unwind info for an object or translation unit, respectively.  */
  68
  69 extern void __register_frame_info (void *, struct object *);
  70
  71 /* Similar, but BEGIN is actually a pointer to a table of unwind entries
  72    for different translation units.  Called from the file generated by
  73    collect2.  */
  74 extern void __register_frame_info_table (void *, struct object *);
  75
  76 /* Called from crtend.o to deregister the unwind info for an object.  */
  77
  78 extern void *__deregister_frame_info (void *);
  79
  80 /* Called from __throw to find the registers to restore for a given
  81    PC_TARGET.  The caller should allocate a local variable of `struct
  82    frame_state' (declared in frame.h) and pass its address to STATE_IN.
  83    Returns NULL on failure, otherwise returns STATE_IN.  */
  84
  85 extern struct frame_state *__frame_state_for (void *, struct frame_state *);