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 /* For uint32_t and uint64_t */ 24 #include <stdint.h> 25 26 /** 27 * ARM-specific unwind definitions. These are taken from the ARM EHABI 28 * specification. 29 */ 30 typedef enum 31 { 32 _URC_NO_REASON = 0, 33 _URC_OK = 0, /* operation completed successfully */ 34 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 35 _URC_END_OF_STACK = 5, 36 _URC_HANDLER_FOUND = 6, 37 _URC_INSTALL_CONTEXT = 7, 38 _URC_CONTINUE_UNWIND = 8, 39 _URC_FAILURE = 9, /* unspecified failure of some kind */ 40 _URC_FATAL_PHASE1_ERROR = _URC_FAILURE 41 } _Unwind_Reason_Code; 42 43 typedef int _Unwind_Action; 44 45 typedef uint32_t _Unwind_State; 46 #ifdef __clang__ 47 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 48 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 49 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 50 static const _Unwind_State _US_ACTION_MASK = 3; 51 #else // GCC fails at knowing what a constant expression is 52 # define _US_VIRTUAL_UNWIND_FRAME 0 53 # define _US_UNWIND_FRAME_STARTING 1 54 # define _US_UNWIND_FRAME_RESUME 2 55 # define _US_ACTION_MASK 3 56 #endif 57 58 typedef struct _Unwind_Context _Unwind_Context; 59 60 typedef uint32_t _Unwind_EHT_Header; 61 62 struct _Unwind_Exception 63 { 64 uint64_t exception_class; 65 void (*exception_cleanup)(_Unwind_Reason_Code, struct _Unwind_Exception *); 66 /* Unwinder cache, private fields for the unwinder's use */ 67 struct 68 { 69 uint32_t reserved1; 70 uint32_t reserved2; 71 uint32_t reserved3; 72 uint32_t reserved4; 73 uint32_t reserved5; 74 /* init reserved1 to 0, then don't touch */ 75 } unwinder_cache; 76 /* Propagation barrier cache (valid after phase 1): */ 77 struct 78 { 79 uint32_t sp; 80 uint32_t bitpattern[5]; 81 } barrier_cache; 82 /* Cleanup cache (preserved over cleanup): */ 83 struct 84 { 85 uint32_t bitpattern[4]; 86 } cleanup_cache; 87 /* Pr cache (for pr's benefit): */ 88 struct 89 { 90 /** function start address */ 91 uint32_t fnstart; 92 /** pointer to EHT entry header word */ 93 _Unwind_EHT_Header *ehtp; 94 /** additional data */ 95 uint32_t additional; 96 uint32_t reserved1; 97 } pr_cache; 98 /** Force alignment of next item to 8-byte boundary */ 99 long long int :0; 100 } __attribute__((__aligned__(8))); 101 102 /* Unwinding functions */ 103 _Unwind_Reason_Code _Unwind_RaiseException(struct _Unwind_Exception *ucbp); 104 void _Unwind_Resume(struct _Unwind_Exception *ucbp); 105 void _Unwind_Complete(struct _Unwind_Exception *ucbp); 106 void _Unwind_DeleteException(struct _Unwind_Exception *ucbp); 107 void *_Unwind_GetLanguageSpecificData(struct _Unwind_Context*); 108 109 typedef enum 110 { 111 _UVRSR_OK = 0, 112 _UVRSR_NOT_IMPLEMENTED = 1, 113 _UVRSR_FAILED = 2 114 } _Unwind_VRS_Result; 115 typedef enum 116 { 117 _UVRSC_CORE = 0, 118 _UVRSC_VFP = 1, 119 _UVRSC_WMMXD = 3, 120 _UVRSC_WMMXC = 4 121 } _Unwind_VRS_RegClass; 122 typedef enum 123 { 124 _UVRSD_UINT32 = 0, 125 _UVRSD_VFPX = 1, 126 _UVRSD_UINT64 = 3, 127 _UVRSD_FLOAT = 4, 128 _UVRSD_DOUBLE = 5 129 } _Unwind_VRS_DataRepresentation; 130 131 _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context *context, 132 _Unwind_VRS_RegClass regclass, 133 uint32_t regno, 134 _Unwind_VRS_DataRepresentation representation, 135 void *valuep); 136 _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context *context, 137 _Unwind_VRS_RegClass regclass, 138 uint32_t regno, 139 _Unwind_VRS_DataRepresentation representation, 140 void *valuep); 141 142 /* Return the base-address for data references. */ 143 extern unsigned long _Unwind_GetDataRelBase(struct _Unwind_Context *); 144 145 /* Return the base-address for text references. */ 146 extern unsigned long _Unwind_GetTextRelBase(struct _Unwind_Context *); 147 extern unsigned long _Unwind_GetRegionStart(struct _Unwind_Context *); 148 149 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) (struct _Unwind_Context *, 150 void *); 151 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *); 152 extern _Unwind_Reason_Code 153 _Unwind_Resume_or_Rethrow (struct _Unwind_Exception *); 154 155 /** 156 * The next set of functions are compatibility extensions, implementing Itanium 157 * ABI functions on top of ARM ones. 158 */ 159 160 #define _UA_SEARCH_PHASE 1 161 #define _UA_CLEANUP_PHASE 2 162 #define _UA_HANDLER_FRAME 4 163 #define _UA_FORCE_UNWIND 8 164 165 static inline unsigned long _Unwind_GetGR(struct _Unwind_Context *context, int reg) 166 { 167 unsigned long val; 168 _Unwind_VRS_Get(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 169 return val; 170 } 171 static inline void _Unwind_SetGR(struct _Unwind_Context *context, int reg, unsigned long val) 172 { 173 _Unwind_VRS_Set(context, _UVRSC_CORE, reg, _UVRSD_UINT32, &val); 174 } 175 static inline unsigned long _Unwind_GetIP(_Unwind_Context *context) 176 { 177 // Low bit store the thumb state - discard it 178 return _Unwind_GetGR(context, 15) & ~1; 179 } 180 static inline void _Unwind_SetIP(_Unwind_Context *context, unsigned long val) 181 { 182 // The lowest bit of the instruction pointer indicates whether we're in 183 // thumb or ARM mode. This is assumed to be fixed throughout a function, 184 // so must be propagated when setting the program counter. 185 unsigned long thumbState = _Unwind_GetGR(context, 15) & 1; 186 _Unwind_SetGR(context, 15, (val | thumbState)); 187 } 188 189 /** GNU API function that unwinds the frame */ 190 _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception*, struct _Unwind_Context*); 191 192 193 #define DECLARE_PERSONALITY_FUNCTION(name) \ 194 _Unwind_Reason_Code name(_Unwind_State state,\ 195 struct _Unwind_Exception *exceptionObject,\ 196 struct _Unwind_Context *context); 197 198 #define BEGIN_PERSONALITY_FUNCTION(name) \ 199 _Unwind_Reason_Code name(_Unwind_State state,\ 200 struct _Unwind_Exception *exceptionObject,\ 201 struct _Unwind_Context *context)\ 202 {\ 203 int version = 1;\ 204 uint64_t exceptionClass = exceptionObject->exception_class;\ 205 int actions;\ 206 switch (state)\ 207 {\ 208 default: return _URC_FAILURE;\ 209 case _US_VIRTUAL_UNWIND_FRAME:\ 210 {\ 211 actions = _UA_SEARCH_PHASE;\ 212 break;\ 213 }\ 214 case _US_UNWIND_FRAME_STARTING:\ 215 {\ 216 actions = _UA_CLEANUP_PHASE;\ 217 if (exceptionObject->barrier_cache.sp == _Unwind_GetGR(context, 13))\ 218 {\ 219 actions |= _UA_HANDLER_FRAME;\ 220 }\ 221 break;\ 222 }\ 223 case _US_UNWIND_FRAME_RESUME:\ 224 {\ 225 return continueUnwinding(exceptionObject, context);\ 226 break;\ 227 }\ 228 }\ 229 _Unwind_SetGR (context, 12, reinterpret_cast<unsigned long>(exceptionObject));\ 230 231 #define CALL_PERSONALITY_FUNCTION(name) name(state,exceptionObject,context) 232