unwind.h revision 7de001102cb4eb6dcafd617fa212507bb1888f07 
1/* Header file for the ARM EABI unwinder
2   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
3   Free Software Foundation, Inc.
4   Contributed by Paul Brook
5
6   This file is free software; you can redistribute it and/or modify it
7   under the terms of the GNU General Public License as published by the
8   Free Software Foundation; either version 3, or (at your option) any
9   later version.
10
11   This file is distributed in the hope that it will be useful, but
12   WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   General Public License for more details.
15
16   Under Section 7 of GPL version 3, you are granted additional
17   permissions described in the GCC Runtime Library Exception, version
18   3.1, as published by the Free Software Foundation.
19
20   You should have received a copy of the GNU General Public License and
21   a copy of the GCC Runtime Library Exception along with this program;
22   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23   <http://www.gnu.org/licenses/>.  */
24
25/* Language-independent unwinder header public defines.  This contains both
26   ABI defined objects, and GNU support routines.  */
27
28#ifndef UNWIND_ARM_H
29#define UNWIND_ARM_H
30
31#define __ARM_EABI_UNWINDER__ 1
32
33#ifdef __cplusplus
34extern "C" {
35#endif
36  typedef unsigned _Unwind_Word __attribute__((__mode__(__word__)));
37  typedef signed _Unwind_Sword __attribute__((__mode__(__word__)));
38  typedef unsigned _Unwind_Ptr __attribute__((__mode__(__pointer__)));
39  typedef unsigned _Unwind_Internal_Ptr __attribute__((__mode__(__pointer__)));
40  typedef _Unwind_Word _uw;
41  typedef unsigned _uw64 __attribute__((mode(__DI__)));
42  typedef unsigned _uw16 __attribute__((mode(__HI__)));
43  typedef unsigned _uw8 __attribute__((mode(__QI__)));
44
45  typedef enum
46    {
47      _URC_OK = 0,       /* operation completed successfully */
48      _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
49      _URC_END_OF_STACK = 5,
50      _URC_HANDLER_FOUND = 6,
51      _URC_INSTALL_CONTEXT = 7,
52      _URC_CONTINUE_UNWIND = 8,
53      _URC_FAILURE = 9   /* unspecified failure of some kind */
54    }
55  _Unwind_Reason_Code;
56
57  typedef enum
58    {
59      _US_VIRTUAL_UNWIND_FRAME = 0,
60      _US_UNWIND_FRAME_STARTING = 1,
61      _US_UNWIND_FRAME_RESUME = 2,
62      _US_ACTION_MASK = 3,
63      _US_FORCE_UNWIND = 8,
64      _US_END_OF_STACK = 16
65    }
66  _Unwind_State;
67
68  /* Provided only for for compatibility with existing code.  */
69  typedef int _Unwind_Action;
70#define _UA_SEARCH_PHASE	1
71#define _UA_CLEANUP_PHASE	2
72#define _UA_HANDLER_FRAME	4
73#define _UA_FORCE_UNWIND	8
74#define _UA_END_OF_STACK	16
75#define _URC_NO_REASON 	_URC_OK
76
77  typedef struct _Unwind_Control_Block _Unwind_Control_Block;
78  typedef struct _Unwind_Context _Unwind_Context;
79  typedef _uw _Unwind_EHT_Header;
80
81
82  /* UCB: */
83
84  struct _Unwind_Control_Block
85    {
86      char exception_class[8];
87      void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *);
88      /* Unwinder cache, private fields for the unwinder's use */
89      struct
90	{
91	  _uw reserved1;  /* Forced unwind stop fn, 0 if not forced */
92	  _uw reserved2;  /* Personality routine address */
93	  _uw reserved3;  /* Saved callsite address */
94	  _uw reserved4;  /* Forced unwind stop arg */
95	  _uw reserved5;
96	}
97      unwinder_cache;
98      /* Propagation barrier cache (valid after phase 1): */
99      struct
100	{
101	  _uw sp;
102	  _uw bitpattern[5];
103	}
104      barrier_cache;
105      /* Cleanup cache (preserved over cleanup): */
106      struct
107	{
108	  _uw bitpattern[4];
109	}
110      cleanup_cache;
111      /* Pr cache (for pr's benefit): */
112      struct
113	{
114	  _uw fnstart;			/* function start address */
115	  _Unwind_EHT_Header *ehtp;	/* pointer to EHT entry header word */
116	  _uw additional;		/* additional data */
117	  _uw reserved1;
118	}
119      pr_cache;
120      long long int :0;	/* Force alignment to 8-byte boundary */
121    };
122
123  /* Virtual Register Set*/
124
125  typedef enum
126    {
127      _UVRSC_CORE = 0,      /* integer register */
128      _UVRSC_VFP = 1,       /* vfp */
129      _UVRSC_FPA = 2,       /* fpa */
130      _UVRSC_WMMXD = 3,     /* Intel WMMX data register */
131      _UVRSC_WMMXC = 4      /* Intel WMMX control register */
132    }
133  _Unwind_VRS_RegClass;
134
135  typedef enum
136    {
137      _UVRSD_UINT32 = 0,
138      _UVRSD_VFPX = 1,
139      _UVRSD_FPAX = 2,
140      _UVRSD_UINT64 = 3,
141      _UVRSD_FLOAT = 4,
142      _UVRSD_DOUBLE = 5
143    }
144  _Unwind_VRS_DataRepresentation;
145
146  typedef enum
147    {
148      _UVRSR_OK = 0,
149      _UVRSR_NOT_IMPLEMENTED = 1,
150      _UVRSR_FAILED = 2
151    }
152  _Unwind_VRS_Result;
153
154  /* Frame unwinding state.  */
155  typedef struct
156    {
157      /* The current word (bytes packed msb first).  */
158      _uw data;
159      /* Pointer to the next word of data.  */
160      _uw *next;
161      /* The number of bytes left in this word.  */
162      _uw8 bytes_left;
163      /* The number of words pointed to by ptr.  */
164      _uw8 words_left;
165    }
166  __gnu_unwind_state;
167
168  typedef _Unwind_Reason_Code (*personality_routine) (_Unwind_State,
169      _Unwind_Control_Block *, _Unwind_Context *);
170
171  _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *, _Unwind_VRS_RegClass,
172                                     _uw, _Unwind_VRS_DataRepresentation,
173                                     void *);
174
175  _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *, _Unwind_VRS_RegClass,
176                                     _uw, _Unwind_VRS_DataRepresentation,
177                                     void *);
178
179  _Unwind_VRS_Result _Unwind_VRS_Pop(_Unwind_Context *, _Unwind_VRS_RegClass,
180                                     _uw, _Unwind_VRS_DataRepresentation);
181
182
183  /* Support functions for the PR.  */
184#define _Unwind_Exception _Unwind_Control_Block
185  typedef char _Unwind_Exception_Class[8];
186
187  void * _Unwind_GetLanguageSpecificData (_Unwind_Context *);
188  _Unwind_Ptr _Unwind_GetRegionStart (_Unwind_Context *);
189
190  /* These two should never be used.  */
191  _Unwind_Ptr _Unwind_GetDataRelBase (_Unwind_Context *);
192  _Unwind_Ptr _Unwind_GetTextRelBase (_Unwind_Context *);
193
194  /* Interface functions: */
195  _Unwind_Reason_Code _Unwind_RaiseException(_Unwind_Control_Block *ucbp);
196  void __attribute__((noreturn)) _Unwind_Resume(_Unwind_Control_Block *ucbp);
197  _Unwind_Reason_Code _Unwind_Resume_or_Rethrow (_Unwind_Control_Block *ucbp);
198
199  typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn)
200       (int, _Unwind_Action, _Unwind_Exception_Class,
201	_Unwind_Control_Block *, struct _Unwind_Context *, void *);
202  _Unwind_Reason_Code _Unwind_ForcedUnwind (_Unwind_Control_Block *,
203					    _Unwind_Stop_Fn, void *);
204  /* @@@ Use unwind data to perform a stack backtrace.  The trace callback
205     is called for every stack frame in the call chain, but no cleanup
206     actions are performed.  */
207  typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) (_Unwind_Context *, void *);
208  _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn,
209					void*);
210
211  _Unwind_Word _Unwind_GetCFA (struct _Unwind_Context *);
212  void _Unwind_Complete(_Unwind_Control_Block *ucbp);
213  void _Unwind_DeleteException (_Unwind_Exception *);
214
215  _Unwind_Reason_Code __gnu_unwind_frame (_Unwind_Control_Block *,
216					  _Unwind_Context *);
217  _Unwind_Reason_Code __gnu_unwind_execute (_Unwind_Context *,
218					    __gnu_unwind_state *);
219
220  /* Decode an R_ARM_TARGET2 relocation.  */
221  static inline _Unwind_Word
222  _Unwind_decode_target2 (_Unwind_Word ptr)
223    {
224      _Unwind_Word tmp;
225
226      tmp = *(_Unwind_Word *) ptr;
227      /* Zero values are always NULL.  */
228      if (!tmp)
229	return 0;
230
231#if (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__)
232      /* Pc-relative indirect.  */
233      tmp += ptr;
234      tmp = *(_Unwind_Word *) tmp;
235#elif defined(__symbian__) || defined(__uClinux__)
236      /* Absolute pointer.  Nothing more to do.  */
237#else
238      /* Pc-relative pointer.  */
239      tmp += ptr;
240#endif
241      return tmp;
242    }
243
244  static inline _Unwind_Word
245  _Unwind_GetGR (_Unwind_Context *context, int regno)
246    {
247      _uw val;
248      _Unwind_VRS_Get (context, _UVRSC_CORE, regno, _UVRSD_UINT32, &val);
249      return val;
250    }
251
252  /* Return the address of the instruction, not the actual IP value.  */
253#define _Unwind_GetIP(context) \
254  (_Unwind_GetGR (context, 15) & ~(_Unwind_Word)1)
255
256#define _Unwind_GetIPInfo(context, ip_before_insn) \
257  (*ip_before_insn = 0, _Unwind_GetGR (context, 15) & ~(_Unwind_Word)1)
258
259  static inline void
260  _Unwind_SetGR (_Unwind_Context *context, int regno, _Unwind_Word val)
261    {
262      _Unwind_VRS_Set (context, _UVRSC_CORE, regno, _UVRSD_UINT32, &val);
263    }
264
265  /* The dwarf unwinder doesn't understand arm/thumb state.  We assume the
266     landing pad uses the same instruction set as the call site.  */
267#define _Unwind_SetIP(context, val) \
268  _Unwind_SetGR (context, 15, val | (_Unwind_GetGR (context, 15) & 1))
269
270/* leb128 type numbers have a potentially unlimited size.
271   The target of the following definitions of _sleb128_t and _uleb128_t
272   is to have efficient data types large enough to hold the leb128 type
273   numbers used in the unwind code.  */
274typedef long _sleb128_t;
275typedef unsigned long _uleb128_t;
276
277#ifdef __cplusplus
278}   /* extern "C" */
279#endif
280
281#endif /* defined UNWIND_ARM_H */
282