1 /* 2 * Copyright 2012 David Chisnall. All rights reserved. 3 * 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: 10 * 11 * The above copyright notice and this permission notice shall be 12 * included in all copies or substantial portions of the Software. 13 * 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. 21 */ 22 23 /** 24 * ARM-specific unwind definitions. These are taken from the ARM EHABI 25 * specification. 26 */ 27 typedef enum 28 { 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; 38 39 typedef int _Unwind_Action; 40 41 typedef uint32_t _Unwind_State; 42 #ifdef __clang__ 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 52 #endif 53 54 typedef struct _Unwind_Context _Unwind_Context; 55 56 typedef uint32_t _Unwind_EHT_Header; 57 58 struct _Unwind_Exception 59 { 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 */ 63 struct 64 { 65 uint32_t reserved1; 66 uint32_t reserved2; 67 uint32_t reserved3; 68 uint32_t reserved4; 69 uint32_t reserved5; 70 /* init reserved1 to 0, then don't touch */ 71 } unwinder_cache; 72 /* Propagation barrier cache (valid after phase 1): */ 73 struct 74 { 75 uint32_t sp; 76 uint32_t bitpattern[5]; 77 } barrier_cache; 78 /* Cleanup cache (preserved over cleanup): */ 79 struct 80 { 81 uint32_t bitpattern[4]; 82 } cleanup_cache; 83 /* Pr cache (for pr's benefit): */ 84 struct 85 { 86 /** function start address */ 87 uint32_t fnstart; 88 /** pointer to EHT entry header word */ 89 _Unwind_EHT_Header *ehtp; 90 /** additional data */ 91 uint32_t additional; 92 uint32_t reserved1; 93 } pr_cache; 94 /** Force alignment of next item to 8-byte boundary */ 95 long long int :0; 96 }; 97 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*); 104 105 typedef enum 106 { 107 _UVRSR_OK = 0, 108 _UVRSR_NOT_IMPLEMENTED = 1, 109 _UVRSR_FAILED = 2 110 } _Unwind_VRS_Result; 111 typedef enum 112 { 113 _UVRSC_CORE = 0, 114 _UVRSC_VFP = 1, 115 _UVRSC_WMMXD = 3, 116 _UVRSC_WMMXC = 4 117 } _Unwind_VRS_RegClass; 118 typedef enum 119 { 120 _UVRSD_UINT32 = 0, 121 _UVRSD_VFPX = 1, 122 _UVRSD_UINT64 = 3, 123 _UVRSD_FLOAT = 4, 124 _UVRSD_DOUBLE = 5 125 } _Unwind_VRS_DataRepresentation; 126 127 _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *context, 128 _Unwind_VRS_RegClass regclass, 129 uint32_t regno, 130 _Unwind_VRS_DataRepresentation representation, 131 void *valuep); 132 _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *context, 133 _Unwind_VRS_RegClass regclass, 134 uint32_t regno, 135 _Unwind_VRS_DataRepresentation representation, 136 void *valuep); 137 138 /* Return the base-address for data references. */ 139 extern unsigned long _Unwind_GetDataRelBase(struct _Unwind_Context *); 140 141 /* 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 *); 144 145 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) (struct _Unwind_Context *, 146 void *); 147 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *); 148 extern _Unwind_Reason_Code 149 _Unwind_Resume_or_Rethrow (struct _Unwind_Exception *); 150 151 /** 152 * The next set of functions are compatibility extensions, implementing Itanium 153 * ABI functions on top of ARM ones. 154 */ 155 156 #define _UA_SEARCH_PHASE 1 157 #define _UA_CLEANUP_PHASE 2 158 #define _UA_HANDLER_FRAME 4 159 #define _UA_FORCE_UNWIND 8 160 161 static inline unsigned long _Unwind_GetGR(struct _Unwind_Context *context, int reg) 162 { 163 unsigned long val; 164 _Unwind_VRS_Get(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 165 return val; 166 } 167 static inline void _Unwind_SetGR(struct _Unwind_Context *context, int reg, unsigned long val) 168 { 169 _Unwind_VRS_Set(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 170 } 171 static inline unsigned long _Unwind_GetIP(_Unwind_Context *context) 172 { 173 // Low bit store the thumb state - discard it 174 return _Unwind_GetGR(context, 15) & ~1; 175 } 176 static inline void _Unwind_SetIP(_Unwind_Context *context, unsigned long val) 177 { 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)); 183 } 184 185 /** GNU API function that unwinds the frame */ 186 _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception*, struct _Unwind_Context*); 187 188 189 #define DECLARE_PERSONALITY_FUNCTION(name) \ 190 _Unwind_Reason_Code name(_Unwind_State state,\ 191 struct _Unwind_Exception *exceptionObject,\ 192 struct _Unwind_Context *context); 193 194 #define BEGIN_PERSONALITY_FUNCTION(name) \ 195 _Unwind_Reason_Code name(_Unwind_State state,\ 196 struct _Unwind_Exception *exceptionObject,\ 197 struct _Unwind_Context *context)\ 198 {\ 199 int version = 1;\ 200 uint64_t exceptionClass = exceptionObject->exception_class;\ 201 int actions;\ 202 switch (state)\ 203 {\ 204 default: return _URC_FAILURE;\ 205 case _US_VIRTUAL_UNWIND_FRAME:\ 206 {\ 207 actions = _UA_SEARCH_PHASE;\ 208 break;\ 209 }\ 210 case _US_UNWIND_FRAME_STARTING:\ 211 {\ 212 actions = _UA_CLEANUP_PHASE;\ 213 if (exceptionObject->barrier_cache.sp == _Unwind_GetGR(context, 13))\ 214 {\ 215 actions |= _UA_HANDLER_FRAME;\ 216 }\ 217 break;\ 218 }\ 219 case _US_UNWIND_FRAME_RESUME:\ 220 {\ 221 return continueUnwinding(exceptionObject, context);\ 222 break;\ 223 }\ 224 }\ 225 _Unwind_SetGR (context, 12, reinterpret_cast<unsigned long>(exceptionObject));\ 226 227 #define CALL_PERSONALITY_FUNCTION(name) name(state,exceptionObject,context) 228