unwind-arm.h (7453B)
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 uint32_t _Unwind_State; 40 #ifdef __clang__ 41 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 42 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 43 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 44 static const _Unwind_State _US_ACTION_MASK = 3; 45 #else // GCC fails at knowing what a constant expression is 46 # define _US_VIRTUAL_UNWIND_FRAME 0 47 # define _US_UNWIND_FRAME_STARTING 1 48 # define _US_UNWIND_FRAME_RESUME 2 49 # define _US_ACTION_MASK 3 50 #endif 51 52 typedef struct _Unwind_Context _Unwind_Context; 53 54 typedef uint32_t _Unwind_EHT_Header; 55 56 struct _Unwind_Exception 57 { 58 uint64_t exception_class; 59 void (*exception_cleanup)(_Unwind_Reason_Code, struct _Unwind_Exception *); 60 /* Unwinder cache, private fields for the unwinder's use */ 61 struct 62 { 63 uint32_t reserved1; 64 uint32_t reserved2; 65 uint32_t reserved3; 66 uint32_t reserved4; 67 uint32_t reserved5; 68 /* init reserved1 to 0, then don't touch */ 69 } unwinder_cache; 70 /* Propagation barrier cache (valid after phase 1): */ 71 struct 72 { 73 uint32_t sp; 74 uint32_t bitpattern[5]; 75 } barrier_cache; 76 /* Cleanup cache (preserved over cleanup): */ 77 struct 78 { 79 uint32_t bitpattern[4]; 80 } cleanup_cache; 81 /* Pr cache (for pr's benefit): */ 82 struct 83 { 84 /** function start address */ 85 uint32_t fnstart; 86 /** pointer to EHT entry header word */ 87 _Unwind_EHT_Header *ehtp; 88 /** additional data */ 89 uint32_t additional; 90 uint32_t reserved1; 91 } pr_cache; 92 /** Force alignment of next item to 8-byte boundary */ 93 long long int :0; 94 }; 95 96 /* Unwinding functions */ 97 _Unwind_Reason_Code _Unwind_RaiseException(struct _Unwind_Exception *ucbp); 98 void _Unwind_Resume(struct _Unwind_Exception *ucbp); 99 void _Unwind_Complete(struct _Unwind_Exception *ucbp); 100 void _Unwind_DeleteException(struct _Unwind_Exception *ucbp); 101 void *_Unwind_GetLanguageSpecificData(struct _Unwind_Context*); 102 103 typedef enum 104 { 105 _UVRSR_OK = 0, 106 _UVRSR_NOT_IMPLEMENTED = 1, 107 _UVRSR_FAILED = 2 108 } _Unwind_VRS_Result; 109 typedef enum 110 { 111 _UVRSC_CORE = 0, 112 _UVRSC_VFP = 1, 113 _UVRSC_WMMXD = 3, 114 _UVRSC_WMMXC = 4 115 } _Unwind_VRS_RegClass; 116 typedef enum 117 { 118 _UVRSD_UINT32 = 0, 119 _UVRSD_VFPX = 1, 120 _UVRSD_UINT64 = 3, 121 _UVRSD_FLOAT = 4, 122 _UVRSD_DOUBLE = 5 123 } _Unwind_VRS_DataRepresentation; 124 125 _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *context, 126 _Unwind_VRS_RegClass regclass, 127 uint32_t regno, 128 _Unwind_VRS_DataRepresentation representation, 129 void *valuep); 130 _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *context, 131 _Unwind_VRS_RegClass regclass, 132 uint32_t regno, 133 _Unwind_VRS_DataRepresentation representation, 134 void *valuep); 135 136 /* Return the base-address for data references. */ 137 extern unsigned long _Unwind_GetDataRelBase(struct _Unwind_Context *); 138 139 /* Return the base-address for text references. */ 140 extern unsigned long _Unwind_GetTextRelBase(struct _Unwind_Context *); 141 extern unsigned long _Unwind_GetRegionStart(struct _Unwind_Context *); 142 143 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) (struct _Unwind_Context *, 144 void *); 145 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *); 146 extern _Unwind_Reason_Code 147 _Unwind_Resume_or_Rethrow (struct _Unwind_Exception *); 148 149 /** 150 * The next set of functions are compatibility extensions, implementing Itanium 151 * ABI functions on top of ARM ones. 152 */ 153 154 #define _UA_SEARCH_PHASE 1 155 #define _UA_CLEANUP_PHASE 2 156 #define _UA_HANDLER_FRAME 4 157 #define _UA_FORCE_UNWIND 8 158 159 static inline unsigned long _Unwind_GetGR(struct _Unwind_Context *context, int reg) 160 { 161 unsigned long val; 162 _Unwind_VRS_Get(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 163 return val; 164 } 165 static inline void _Unwind_SetGR(struct _Unwind_Context *context, int reg, unsigned long val) 166 { 167 _Unwind_VRS_Set(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 168 } 169 static inline unsigned long _Unwind_GetIP(_Unwind_Context *context) 170 { 171 // Low bit store the thumb state - discard it 172 return _Unwind_GetGR(context, 15) & ~1; 173 } 174 static inline void _Unwind_SetIP(_Unwind_Context *context, unsigned long val) 175 { 176 // The lowest bit of the instruction pointer indicates whether we're in 177 // thumb or ARM mode. This is assumed to be fixed throughout a function, 178 // so must be propagated when setting the program counter. 179 unsigned long thumbState = _Unwind_GetGR(context, 15) & 1; 180 _Unwind_SetGR(context, 15, (val | thumbState)); 181 } 182 183 /** GNU API function that unwinds the frame */ 184 _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception*, struct _Unwind_Context*); 185 186 187 #define DECLARE_PERSONALITY_FUNCTION(name) \ 188 _Unwind_Reason_Code name(_Unwind_State state,\ 189 struct _Unwind_Exception *exceptionObject,\ 190 struct _Unwind_Context *context); 191 192 #define BEGIN_PERSONALITY_FUNCTION(name) \ 193 _Unwind_Reason_Code name(_Unwind_State state,\ 194 struct _Unwind_Exception *exceptionObject,\ 195 struct _Unwind_Context *context)\ 196 {\ 197 int version = 1;\ 198 uint64_t exceptionClass = exceptionObject->exception_class;\ 199 int actions;\ 200 switch (state)\ 201 {\ 202 default: return _URC_FAILURE;\ 203 case _US_VIRTUAL_UNWIND_FRAME:\ 204 {\ 205 actions = _UA_SEARCH_PHASE;\ 206 break;\ 207 }\ 208 case _US_UNWIND_FRAME_STARTING:\ 209 {\ 210 actions = _UA_CLEANUP_PHASE;\ 211 if (exceptionObject->barrier_cache.sp == _Unwind_GetGR(context, 13))\ 212 {\ 213 actions |= _UA_HANDLER_FRAME;\ 214 }\ 215 break;\ 216 }\ 217 case _US_UNWIND_FRAME_RESUME:\ 218 {\ 219 return continueUnwinding(exceptionObject, context);\ 220 break;\ 221 }\ 222 }\ 223 _Unwind_SetGR (context, 12, reinterpret_cast<unsigned long>(exceptionObject));\ 224 225 #define CALL_PERSONALITY_FUNCTION(name) name(state,exceptionObject,context)