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