gcc/unwind-dw2.h

   1 /* DWARF2 frame unwind data structure.
   2    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    In addition to the permissions in the GNU General Public License, the
  13    Free Software Foundation gives you unlimited permission to link the
  14    compiled version of this file into combinations with other programs,
  15    and to distribute those combinations without any restriction coming
  16    from the use of this file.  (The General Public License restrictions
  17    do apply in other respects; for example, they cover modification of
  18    the file, and distribution when not linked into a combined
  19    executable.)
  20
  21    GCC is distributed in the hope that it will be useful, but WITHOUT
  22    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  23    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  24    License for more details.
  25
  26    You should have received a copy of the GNU General Public License
  27    along with GCC; see the file COPYING.  If not, write to the Free
  28    Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  29    02110-1301, USA.  */
  30
  31 /* A target can override (perhaps for backward compatibility) how
  32    many dwarf2 columns are unwound.  */
  33 #ifndef DWARF_FRAME_REGISTERS
  34 #define DWARF_FRAME_REGISTERS FIRST_PSEUDO_REGISTER
  35 #endif
  36
  37 /* The result of interpreting the frame unwind info for a frame.
  38    This is all symbolic at this point, as none of the values can
  39    be resolved until the target pc is located.  */
  40 typedef struct
  41 {
  42   /* Each register save state can be described in terms of a CFA slot,
  43      another register, or a location expression.  */
  44   struct frame_state_reg_info
  45   {
  46     struct {
  47       union {
  48         _Unwind_Word reg;
  49         _Unwind_Sword offset;
  50         const unsigned char *exp;
  51       } loc;
  52       enum {
  53         REG_UNSAVED,
  54         REG_SAVED_OFFSET,
  55         REG_SAVED_REG,
  56         REG_SAVED_EXP
  57       } how;
  58     } reg[DWARF_FRAME_REGISTERS+1];
  59
  60     /* Used to implement DW_CFA_remember_state.  */
  61     struct frame_state_reg_info *prev;
  62   } regs;
  63
  64   /* The CFA can be described in terms of a reg+offset or a
  65      location expression.  */
  66   _Unwind_Sword cfa_offset;
  67   _Unwind_Word cfa_reg;
  68   const unsigned char *cfa_exp;
  69   enum {
  70     CFA_UNSET,
  71     CFA_REG_OFFSET,
  72     CFA_EXP
  73   } cfa_how;
  74
  75   /* The PC described by the current frame state.  */
  76   void *pc;
  77
  78   /* The information we care about from the CIE/FDE.  */
  79   _Unwind_Personality_Fn personality;
  80   _Unwind_Sword data_align;
  81   _Unwind_Word code_align;
  82   _Unwind_Word retaddr_column;
  83   unsigned char fde_encoding;
  84   unsigned char lsda_encoding;
  85   unsigned char saw_z;
  86   void *eh_ptr;
  87 } _Unwind_FrameState;
  88