2 * Copyright 2012 David Chisnall. All rights reserved.
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to
6 * deal in the Software without restriction, including without limitation the
7 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
8 * sell copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice shall be
12 * included in all copies or substantial portions of the Software.
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
15 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
17 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
18 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
19 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
20 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 * ARM-specific unwind definitions. These are taken from the ARM EHABI
29 _URC_OK = 0, /* operation completed successfully */
30 _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
31 _URC_END_OF_STACK = 5,
32 _URC_HANDLER_FOUND = 6,
33 _URC_INSTALL_CONTEXT = 7,
34 _URC_CONTINUE_UNWIND = 8,
35 _URC_FAILURE = 9, /* unspecified failure of some kind */
36 _URC_FATAL_PHASE1_ERROR = _URC_FAILURE
37 } _Unwind_Reason_Code;
39 typedef int _Unwind_Action;
41 typedef uint32_t _Unwind_State;
43 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0;
44 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1;
45 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2;
46 static const _Unwind_State _US_ACTION_MASK = 3;
47 #else // GCC fails at knowing what a constant expression is
48 # define _US_VIRTUAL_UNWIND_FRAME 0
49 # define _US_UNWIND_FRAME_STARTING 1
50 # define _US_UNWIND_FRAME_RESUME 2
51 # define _US_ACTION_MASK 3
54 typedef struct _Unwind_Context _Unwind_Context;
56 typedef uint32_t _Unwind_EHT_Header;
58 struct _Unwind_Exception
60 uint64_t exception_class;
61 void (*exception_cleanup)(_Unwind_Reason_Code, struct _Unwind_Exception *);
62 /* Unwinder cache, private fields for the unwinder's use */
70 /* init reserved1 to 0, then don't touch */
72 /* Propagation barrier cache (valid after phase 1): */
76 uint32_t bitpattern[5];
78 /* Cleanup cache (preserved over cleanup): */
81 uint32_t bitpattern[4];
83 /* Pr cache (for pr's benefit): */
86 /** function start address */
88 /** pointer to EHT entry header word */
89 _Unwind_EHT_Header *ehtp;
90 /** additional data */
94 /** Force alignment of next item to 8-byte boundary */
98 /* Unwinding functions */
99 _Unwind_Reason_Code _Unwind_RaiseException(struct _Unwind_Exception *ucbp);
100 void _Unwind_Resume(struct _Unwind_Exception *ucbp);
101 void _Unwind_Complete(struct _Unwind_Exception *ucbp);
102 void _Unwind_DeleteException(struct _Unwind_Exception *ucbp);
103 void *_Unwind_GetLanguageSpecificData(struct _Unwind_Context*);
108 _UVRSR_NOT_IMPLEMENTED = 1,
110 } _Unwind_VRS_Result;
117 } _Unwind_VRS_RegClass;
125 } _Unwind_VRS_DataRepresentation;
127 _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *context,
128 _Unwind_VRS_RegClass regclass,
130 _Unwind_VRS_DataRepresentation representation,
132 _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *context,
133 _Unwind_VRS_RegClass regclass,
135 _Unwind_VRS_DataRepresentation representation,
138 /* Return the base-address for data references. */
139 extern unsigned long _Unwind_GetDataRelBase(struct _Unwind_Context *);
141 /* Return the base-address for text references. */
142 extern unsigned long _Unwind_GetTextRelBase(struct _Unwind_Context *);
143 extern unsigned long _Unwind_GetRegionStart(struct _Unwind_Context *);
145 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) (struct _Unwind_Context *,
147 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *);
148 extern _Unwind_Reason_Code
149 _Unwind_Resume_or_Rethrow (struct _Unwind_Exception *);
152 * The next set of functions are compatibility extensions, implementing Itanium
153 * ABI functions on top of ARM ones.
156 #define _UA_SEARCH_PHASE 1
157 #define _UA_CLEANUP_PHASE 2
158 #define _UA_HANDLER_FRAME 4
159 #define _UA_FORCE_UNWIND 8
161 static inline unsigned long _Unwind_GetGR(struct _Unwind_Context *context, int reg)
164 _Unwind_VRS_Get(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val);
167 static inline void _Unwind_SetGR(struct _Unwind_Context *context, int reg, unsigned long val)
169 _Unwind_VRS_Set(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val);
171 static inline unsigned long _Unwind_GetIP(_Unwind_Context *context)
173 // Low bit store the thumb state - discard it
174 return _Unwind_GetGR(context, 15) & ~1;
176 static inline void _Unwind_SetIP(_Unwind_Context *context, unsigned long val)
178 // The lowest bit of the instruction pointer indicates whether we're in
179 // thumb or ARM mode. This is assumed to be fixed throughout a function,
180 // so must be propagated when setting the program counter.
181 unsigned long thumbState = _Unwind_GetGR(context, 15) & 1;
182 _Unwind_SetGR(context, 15, (val | thumbState));
185 /** GNU API function that unwinds the frame */
186 _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception*, struct _Unwind_Context*);
189 #define DECLARE_PERSONALITY_FUNCTION(name) \
190 _Unwind_Reason_Code name(_Unwind_State state,\
191 struct _Unwind_Exception *exceptionObject,\
192 struct _Unwind_Context *context);
194 #define BEGIN_PERSONALITY_FUNCTION(name) \
195 _Unwind_Reason_Code name(_Unwind_State state,\
196 struct _Unwind_Exception *exceptionObject,\
197 struct _Unwind_Context *context)\
200 uint64_t exceptionClass = exceptionObject->exception_class;\
204 default: return _URC_FAILURE;\
205 case _US_VIRTUAL_UNWIND_FRAME:\
207 actions = _UA_SEARCH_PHASE;\
210 case _US_UNWIND_FRAME_STARTING:\
212 actions = _UA_CLEANUP_PHASE;\
213 if (exceptionObject->barrier_cache.sp == _Unwind_GetGR(context, 13))\
215 actions |= _UA_HANDLER_FRAME;\
219 case _US_UNWIND_FRAME_RESUME:\
221 return continueUnwinding(exceptionObject, context);\
225 _Unwind_SetGR (context, 12, reinterpret_cast<unsigned long>(exceptionObject));\
227 #define CALL_PERSONALITY_FUNCTION(name) name(state,exceptionObject,context)