sysdeps/arm/unwind.h

   1 /* Header file for the ARM EABI unwinder
   2    Copyright (C) 2003-2017 Free Software Foundation, Inc.
   3    Contributed by Paul Brook
   4
   5    This file is free software; you can redistribute it and/or modify it
   6    under the terms of the GNU General Public License as published by the
   7    Free Software Foundation; either version 2, or (at your option) any
   8    later version.
   9
  10    In addition to the permissions in the GNU General Public License, the
  11    Free Software Foundation gives you unlimited permission to link the
  12    compiled version of this file into combinations with other programs,
  13    and to distribute those combinations without any restriction coming
  14    from the use of this file.  (The General Public License restrictions
  15    do apply in other respects; for example, they cover modification of
  16    the file, and distribution when not linked into a combine
  17    executable.)
  18
  19    This file is distributed in the hope that it will be useful, but
  20    WITHOUT ANY WARRANTY; without even the implied warranty of
  21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22    General Public License for more details.
  23
  24    You should have received a copy of the GNU General Public License
  25    along with this program.  If not, see
  26    <http://www.gnu.org/licenses/>.  */
  27
  28 /* Language-independent unwinder header public defines.  This contains both
  29    ABI defined objects, and GNU support routines.  */
  30
  31 #ifndef UNWIND_ARM_H
  32 #define UNWIND_ARM_H
  33
  34 #define __ARM_EABI_UNWINDER__ 1
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39   typedef unsigned _Unwind_Word __attribute__((__mode__(__word__)));
  40   typedef signed _Unwind_Sword __attribute__((__mode__(__word__)));
  41   typedef unsigned _Unwind_Ptr __attribute__((__mode__(__pointer__)));
  42   typedef unsigned _Unwind_Internal_Ptr __attribute__((__mode__(__pointer__)));
  43   typedef _Unwind_Word _uw;
  44   typedef unsigned _uw64 __attribute__((mode(__DI__)));
  45   typedef unsigned _uw16 __attribute__((mode(__HI__)));
  46   typedef unsigned _uw8 __attribute__((mode(__QI__)));
  47
  48   typedef enum
  49     {
  50       _URC_OK = 0,       /* operation completed successfully */
  51       _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
  52       _URC_END_OF_STACK = 5,
  53       _URC_HANDLER_FOUND = 6,
  54       _URC_INSTALL_CONTEXT = 7,
  55       _URC_CONTINUE_UNWIND = 8,
  56       _URC_FAILURE = 9   /* unspecified failure of some kind */
  57     }
  58   _Unwind_Reason_Code;
  59
  60   typedef enum
  61     {
  62       _US_VIRTUAL_UNWIND_FRAME = 0,
  63       _US_UNWIND_FRAME_STARTING = 1,
  64       _US_UNWIND_FRAME_RESUME = 2,
  65       _US_ACTION_MASK = 3,
  66       _US_FORCE_UNWIND = 8,
  67       _US_END_OF_STACK = 16
  68     }
  69   _Unwind_State;
  70
  71   /* Provided only for for compatibility with existing code.  */
  72   typedef int _Unwind_Action;
  73 #define _UA_SEARCH_PHASE        1
  74 #define _UA_CLEANUP_PHASE       2
  75 #define _UA_HANDLER_FRAME       4
  76 #define _UA_FORCE_UNWIND        8
  77 #define _UA_END_OF_STACK        16
  78 #define _URC_NO_REASON  _URC_OK
  79
  80   typedef struct _Unwind_Control_Block _Unwind_Control_Block;
  81   typedef struct _Unwind_Context _Unwind_Context;
  82   typedef _uw _Unwind_EHT_Header;
  83
  84
  85   /* UCB: */
  86
  87   struct _Unwind_Control_Block
  88     {
  89 #ifdef _LIBC
  90       /* For the benefit of code which assumes this is a scalar.  All
  91          glibc ever does is clear it.  */
  92       _uw64 exception_class;
  93 #else
  94       char exception_class[8];
  95 #endif
  96       void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *);
  97       /* Unwinder cache, private fields for the unwinder's use */
  98       struct
  99         {
 100           _uw reserved1;  /* Forced unwind stop fn, 0 if not forced */
 101           _uw reserved2;  /* Personality routine address */
 102           _uw reserved3;  /* Saved callsite address */
 103           _uw reserved4;  /* Forced unwind stop arg */
 104           _uw reserved5;
 105         }
 106       unwinder_cache;
 107       /* Propagation barrier cache (valid after phase 1): */
 108       struct
 109         {
 110           _uw sp;
 111           _uw bitpattern[5];
 112         }
 113       barrier_cache;
 114       /* Cleanup cache (preserved over cleanup): */
 115       struct
 116         {
 117           _uw bitpattern[4];
 118         }
 119       cleanup_cache;
 120       /* Pr cache (for pr's benefit): */
 121       struct
 122         {
 123           _uw fnstart;                  /* function start address */
 124           _Unwind_EHT_Header *ehtp;     /* pointer to EHT entry header word */
 125           _uw additional;               /* additional data */
 126           _uw reserved1;
 127         }
 128       pr_cache;
 129       long long int :0; /* Force alignment to 8-byte boundary */
 130     };
 131
 132   /* Virtual Register Set*/
 133
 134   typedef enum
 135     {
 136       _UVRSC_CORE = 0,      /* integer register */
 137       _UVRSC_VFP = 1,       /* vfp */
 138       _UVRSC_FPA = 2,       /* fpa */
 139       _UVRSC_WMMXD = 3,     /* Intel WMMX data register */
 140       _UVRSC_WMMXC = 4      /* Intel WMMX control register */
 141     }
 142   _Unwind_VRS_RegClass;
 143
 144   typedef enum
 145     {
 146       _UVRSD_UINT32 = 0,
 147       _UVRSD_VFPX = 1,
 148       _UVRSD_FPAX = 2,
 149       _UVRSD_UINT64 = 3,
 150       _UVRSD_FLOAT = 4,
 151       _UVRSD_DOUBLE = 5
 152     }
 153   _Unwind_VRS_DataRepresentation;
 154
 155   typedef enum
 156     {
 157       _UVRSR_OK = 0,
 158       _UVRSR_NOT_IMPLEMENTED = 1,
 159       _UVRSR_FAILED = 2
 160     }
 161   _Unwind_VRS_Result;
 162
 163   /* Frame unwinding state.  */
 164   typedef struct
 165     {
 166       /* The current word (bytes packed msb first).  */
 167       _uw data;
 168       /* Pointer to the next word of data.  */
 169       _uw *next;
 170       /* The number of bytes left in this word.  */
 171       _uw8 bytes_left;
 172       /* The number of words pointed to by ptr.  */
 173       _uw8 words_left;
 174     }
 175   __gnu_unwind_state;
 176
 177   typedef _Unwind_Reason_Code (*personality_routine) (_Unwind_State,
 178       _Unwind_Control_Block *, _Unwind_Context *);
 179
 180   _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *, _Unwind_VRS_RegClass,
 181                                      _uw, _Unwind_VRS_DataRepresentation,
 182                                      void *);
 183
 184   _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *, _Unwind_VRS_RegClass,
 185                                      _uw, _Unwind_VRS_DataRepresentation,
 186                                      void *);
 187
 188   _Unwind_VRS_Result _Unwind_VRS_Pop(_Unwind_Context *, _Unwind_VRS_RegClass,
 189                                      _uw, _Unwind_VRS_DataRepresentation);
 190
 191
 192   /* Support functions for the PR.  */
 193 #define _Unwind_Exception _Unwind_Control_Block
 194   typedef char _Unwind_Exception_Class[8];
 195
 196   void * _Unwind_GetLanguageSpecificData (_Unwind_Context *);
 197   _Unwind_Ptr _Unwind_GetRegionStart (_Unwind_Context *);
 198
 199   /* These two should never be used.  */
 200   _Unwind_Ptr _Unwind_GetDataRelBase (_Unwind_Context *);
 201   _Unwind_Ptr _Unwind_GetTextRelBase (_Unwind_Context *);
 202
 203   /* Interface functions: */
 204   _Unwind_Reason_Code _Unwind_RaiseException(_Unwind_Control_Block *ucbp);
 205   void __attribute__((noreturn)) _Unwind_Resume(_Unwind_Control_Block *ucbp);
 206   _Unwind_Reason_Code _Unwind_Resume_or_Rethrow (_Unwind_Control_Block *ucbp);
 207
 208   typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn)
 209        (int, _Unwind_Action, _Unwind_Exception_Class,
 210         _Unwind_Control_Block *, struct _Unwind_Context *, void *);
 211   _Unwind_Reason_Code _Unwind_ForcedUnwind (_Unwind_Control_Block *,
 212                                             _Unwind_Stop_Fn, void *);
 213   _Unwind_Word _Unwind_GetCFA (struct _Unwind_Context *);
 214   void _Unwind_Complete(_Unwind_Control_Block *ucbp);
 215   void _Unwind_DeleteException (_Unwind_Exception *);
 216
 217   _Unwind_Reason_Code __gnu_unwind_frame (_Unwind_Control_Block *,
 218                                           _Unwind_Context *);
 219   _Unwind_Reason_Code __gnu_unwind_execute (_Unwind_Context *,
 220                                             __gnu_unwind_state *);
 221
 222   /* Decode an R_ARM_TARGET2 relocation.  */
 223   static inline _Unwind_Word
 224   _Unwind_decode_target2 (_Unwind_Word ptr)
 225     {
 226       _Unwind_Word tmp;
 227
 228       tmp = *(_Unwind_Word *) ptr;
 229       /* Zero values are always NULL.  */
 230       if (!tmp)
 231         return 0;
 232
 233 #if defined(linux) || defined(__NetBSD__)
 234       /* Pc-relative indirect.  */
 235       tmp += ptr;
 236       tmp = *(_Unwind_Word *) tmp;
 237 #elif defined(__symbian__)
 238       /* Absolute pointer.  Nothing more to do.  */
 239 #else
 240       /* Pc-relative pointer.  */
 241       tmp += ptr;
 242 #endif
 243       return tmp;
 244     }
 245
 246   static inline _Unwind_Word
 247   _Unwind_GetGR (_Unwind_Context *context, int regno)
 248     {
 249       _uw val;
 250       _Unwind_VRS_Get (context, _UVRSC_CORE, regno, _UVRSD_UINT32, &val);
 251       return val;
 252     }
 253
 254   /* Return the address of the instruction, not the actual IP value.  */
 255 #define _Unwind_GetIP(context) \
 256   (_Unwind_GetGR (context, 15) & ~(_Unwind_Word)1)
 257
 258   static inline void
 259   _Unwind_SetGR (_Unwind_Context *context, int regno, _Unwind_Word val)
 260     {
 261       _Unwind_VRS_Set (context, _UVRSC_CORE, regno, _UVRSD_UINT32, &val);
 262     }
 263
 264   /* The dwarf unwinder doesn't understand arm/thumb state.  We assume the
 265      landing pad uses the same instruction set as the call site.  */
 266 #define _Unwind_SetIP(context, val) \
 267   _Unwind_SetGR (context, 15, val | (_Unwind_GetGR (context, 15) & 1))
 268
 269 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)
 270      (struct _Unwind_Context *, void *);
 271
 272 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *);
 273
 274 #ifdef __cplusplus
 275 }   /* extern "C" */
 276 #endif
 277
 278 #endif /* defined UNWIND_ARM_H */