1 //===------------------------------- unwind.h -----------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 // 9 // C++ ABI Level 1 ABI documented at: 10 // http://mentorembedded.github.io/cxx-abi/abi-eh.html 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef __UNWIND_H__ 15 #define __UNWIND_H__ 16 17 #include <__libunwind_config.h> 18 19 #include <stdint.h> 20 #include <stddef.h> 21 22 #if defined(__APPLE__) 23 #define LIBUNWIND_UNAVAIL __attribute__ (( unavailable )) 24 #else 25 #define LIBUNWIND_UNAVAIL 26 #endif 27 28 typedef enum { 29 _URC_NO_REASON = 0, 30 _URC_OK = 0, 31 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 32 _URC_FATAL_PHASE2_ERROR = 2, 33 _URC_FATAL_PHASE1_ERROR = 3, 34 _URC_NORMAL_STOP = 4, 35 _URC_END_OF_STACK = 5, 36 _URC_HANDLER_FOUND = 6, 37 _URC_INSTALL_CONTEXT = 7, 38 _URC_CONTINUE_UNWIND = 8, 39 #if defined(_LIBUNWIND_ARM_EHABI) 40 _URC_FAILURE = 9 41 #endif 42 } _Unwind_Reason_Code; 43 44 typedef enum { 45 _UA_SEARCH_PHASE = 1, 46 _UA_CLEANUP_PHASE = 2, 47 _UA_HANDLER_FRAME = 4, 48 _UA_FORCE_UNWIND = 8, 49 _UA_END_OF_STACK = 16 // gcc extension to C++ ABI 50 } _Unwind_Action; 51 52 typedef struct _Unwind_Context _Unwind_Context; // opaque 53 54 #if defined(_LIBUNWIND_ARM_EHABI) 55 typedef uint32_t _Unwind_State; 56 57 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 58 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 59 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 60 static const _Unwind_State _US_ACTION_MASK = 3; 61 /* Undocumented flag for force unwinding. */ 62 static const _Unwind_State _US_FORCE_UNWIND = 8; 63 64 typedef uint32_t _Unwind_EHT_Header; 65 66 struct _Unwind_Control_Block; 67 typedef struct _Unwind_Control_Block _Unwind_Control_Block; 68 typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */ 69 70 struct _Unwind_Control_Block { 71 uint64_t exception_class; 72 void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block*); 73 74 /* Unwinder cache, private fields for the unwinder's use */ 75 struct { 76 uint32_t reserved1; /* init reserved1 to 0, then don't touch */ 77 uint32_t reserved2; 78 uint32_t reserved3; 79 uint32_t reserved4; 80 uint32_t reserved5; 81 } unwinder_cache; 82 83 /* Propagation barrier cache (valid after phase 1): */ 84 struct { 85 uint32_t sp; 86 uint32_t bitpattern[5]; 87 } barrier_cache; 88 89 /* Cleanup cache (preserved over cleanup): */ 90 struct { 91 uint32_t bitpattern[4]; 92 } cleanup_cache; 93 94 /* Pr cache (for pr's benefit): */ 95 struct { 96 uint32_t fnstart; /* function start address */ 97 _Unwind_EHT_Header* ehtp; /* pointer to EHT entry header word */ 98 uint32_t additional; 99 uint32_t reserved1; 100 } pr_cache; 101 102 long long int :0; /* Enforce the 8-byte alignment */ 103 } __attribute__((__aligned__(8))); 104 105 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 106 (_Unwind_State state, 107 _Unwind_Exception* exceptionObject, 108 struct _Unwind_Context* context); 109 110 typedef _Unwind_Reason_Code (*__personality_routine) 111 (_Unwind_State state, 112 _Unwind_Exception* exceptionObject, 113 struct _Unwind_Context* context); 114 #else 115 struct _Unwind_Context; // opaque 116 struct _Unwind_Exception; // forward declaration 117 typedef struct _Unwind_Exception _Unwind_Exception; 118 119 struct _Unwind_Exception { 120 uint64_t exception_class; 121 void (*exception_cleanup)(_Unwind_Reason_Code reason, 122 _Unwind_Exception *exc); 123 uintptr_t private_1; // non-zero means forced unwind 124 uintptr_t private_2; // holds sp that phase1 found for phase2 to use 125 #if __SIZEOF_POINTER__ == 4 126 // The implementation of _Unwind_Exception uses an attribute mode on the 127 // above fields which has the side effect of causing this whole struct to 128 // round up to 32 bytes in size. To be more explicit, we add pad fields 129 // added for binary compatibility. 130 uint32_t reserved[3]; 131 #endif 132 // The Itanium ABI requires that _Unwind_Exception objects are "double-word 133 // aligned". GCC has interpreted this to mean "use the maximum useful 134 // alignment for the target"; so do we. 135 } __attribute__((__aligned__)); 136 137 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 138 (int version, 139 _Unwind_Action actions, 140 uint64_t exceptionClass, 141 _Unwind_Exception* exceptionObject, 142 struct _Unwind_Context* context, 143 void* stop_parameter ); 144 145 typedef _Unwind_Reason_Code (*__personality_routine) 146 (int version, 147 _Unwind_Action actions, 148 uint64_t exceptionClass, 149 _Unwind_Exception* exceptionObject, 150 struct _Unwind_Context* context); 151 #endif 152 153 #ifdef __cplusplus 154 extern "C" { 155 #endif 156 157 // 158 // The following are the base functions documented by the C++ ABI 159 // 160 #ifdef __USING_SJLJ_EXCEPTIONS__ 161 extern _Unwind_Reason_Code 162 _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object); 163 extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object); 164 #else 165 extern _Unwind_Reason_Code 166 _Unwind_RaiseException(_Unwind_Exception *exception_object); 167 extern void _Unwind_Resume(_Unwind_Exception *exception_object); 168 #endif 169 extern void _Unwind_DeleteException(_Unwind_Exception *exception_object); 170 171 #if defined(_LIBUNWIND_ARM_EHABI) 172 typedef enum { 173 _UVRSC_CORE = 0, /* integer register */ 174 _UVRSC_VFP = 1, /* vfp */ 175 _UVRSC_WMMXD = 3, /* Intel WMMX data register */ 176 _UVRSC_WMMXC = 4 /* Intel WMMX control register */ 177 } _Unwind_VRS_RegClass; 178 179 typedef enum { 180 _UVRSD_UINT32 = 0, 181 _UVRSD_VFPX = 1, 182 _UVRSD_UINT64 = 3, 183 _UVRSD_FLOAT = 4, 184 _UVRSD_DOUBLE = 5 185 } _Unwind_VRS_DataRepresentation; 186 187 typedef enum { 188 _UVRSR_OK = 0, 189 _UVRSR_NOT_IMPLEMENTED = 1, 190 _UVRSR_FAILED = 2 191 } _Unwind_VRS_Result; 192 193 extern void _Unwind_Complete(_Unwind_Exception* exception_object); 194 195 extern _Unwind_VRS_Result 196 _Unwind_VRS_Get(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 197 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 198 void *valuep); 199 200 extern _Unwind_VRS_Result 201 _Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 202 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 203 void *valuep); 204 205 extern _Unwind_VRS_Result 206 _Unwind_VRS_Pop(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 207 uint32_t discriminator, 208 _Unwind_VRS_DataRepresentation representation); 209 #endif 210 211 #if !defined(_LIBUNWIND_ARM_EHABI) 212 213 extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index); 214 extern void _Unwind_SetGR(struct _Unwind_Context *context, int index, 215 uintptr_t new_value); 216 extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context); 217 extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value); 218 219 #else // defined(_LIBUNWIND_ARM_EHABI) 220 221 #if defined(_LIBUNWIND_UNWIND_LEVEL1_EXTERNAL_LINKAGE) 222 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 extern 223 #else 224 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 static __inline__ 225 #endif 226 227 // These are de facto helper functions for ARM, which delegate the function 228 // calls to _Unwind_VRS_Get/Set(). These are not a part of ARM EHABI 229 // specification, thus these function MUST be inlined. Please don't replace 230 // these with the "extern" function declaration; otherwise, the program 231 // including this <unwind.h> header won't be ABI compatible and will result in 232 // link error when we are linking the program with libgcc. 233 234 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 235 uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index) { 236 uintptr_t value = 0; 237 _Unwind_VRS_Get(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); 238 return value; 239 } 240 241 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 242 void _Unwind_SetGR(struct _Unwind_Context *context, int index, 243 uintptr_t value) { 244 _Unwind_VRS_Set(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); 245 } 246 247 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 248 uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) { 249 // remove the thumb-bit before returning 250 return _Unwind_GetGR(context, 15) & (~(uintptr_t)0x1); 251 } 252 253 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 254 void _Unwind_SetIP(struct _Unwind_Context *context, uintptr_t value) { 255 uintptr_t thumb_bit = _Unwind_GetGR(context, 15) & ((uintptr_t)0x1); 256 _Unwind_SetGR(context, 15, value | thumb_bit); 257 } 258 #endif // defined(_LIBUNWIND_ARM_EHABI) 259 260 extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 261 extern uintptr_t 262 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 263 #ifdef __USING_SJLJ_EXCEPTIONS__ 264 extern _Unwind_Reason_Code 265 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 266 _Unwind_Stop_Fn stop, void *stop_parameter); 267 #else 268 extern _Unwind_Reason_Code 269 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, 270 _Unwind_Stop_Fn stop, void *stop_parameter); 271 #endif 272 273 #ifdef __USING_SJLJ_EXCEPTIONS__ 274 typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 275 extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 276 extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); 277 #endif 278 279 // 280 // The following are semi-suppoted extensions to the C++ ABI 281 // 282 283 // 284 // called by __cxa_rethrow(). 285 // 286 #ifdef __USING_SJLJ_EXCEPTIONS__ 287 extern _Unwind_Reason_Code 288 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 289 #else 290 extern _Unwind_Reason_Code 291 _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object); 292 #endif 293 294 // _Unwind_Backtrace() is a gcc extension that walks the stack and calls the 295 // _Unwind_Trace_Fn once per frame until it reaches the bottom of the stack 296 // or the _Unwind_Trace_Fn function returns something other than _URC_NO_REASON. 297 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 298 void *); 299 extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *); 300 301 // _Unwind_GetCFA is a gcc extension that can be called from within a 302 // personality handler to get the CFA (stack pointer before call) of 303 // current frame. 304 extern uintptr_t _Unwind_GetCFA(struct _Unwind_Context *); 305 306 307 // _Unwind_GetIPInfo is a gcc extension that can be called from within a 308 // personality handler. Similar to _Unwind_GetIP() but also returns in 309 // *ipBefore a non-zero value if the instruction pointer is at or before the 310 // instruction causing the unwind. Normally, in a function call, the IP returned 311 // is the return address which is after the call instruction and may be past the 312 // end of the function containing the call instruction. 313 extern uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context, 314 int *ipBefore); 315 316 317 // __register_frame() is used with dynamically generated code to register the 318 // FDE for a generated (JIT) code. The FDE must use pc-rel addressing to point 319 // to its function and optional LSDA. 320 // __register_frame() has existed in all versions of Mac OS X, but in 10.4 and 321 // 10.5 it was buggy and did not actually register the FDE with the unwinder. 322 // In 10.6 and later it does register properly. 323 extern void __register_frame(const void *fde); 324 extern void __deregister_frame(const void *fde); 325 326 // _Unwind_Find_FDE() will locate the FDE if the pc is in some function that has 327 // an associated FDE. Note, Mac OS X 10.6 and later, introduces "compact unwind 328 // info" which the runtime uses in preference to DWARF unwind info. This 329 // function will only work if the target function has an FDE but no compact 330 // unwind info. 331 struct dwarf_eh_bases { 332 uintptr_t tbase; 333 uintptr_t dbase; 334 uintptr_t func; 335 }; 336 extern const void *_Unwind_Find_FDE(const void *pc, struct dwarf_eh_bases *); 337 338 339 // This function attempts to find the start (address of first instruction) of 340 // a function given an address inside the function. It only works if the 341 // function has an FDE (DWARF unwind info). 342 // This function is unimplemented on Mac OS X 10.6 and later. Instead, use 343 // _Unwind_Find_FDE() and look at the dwarf_eh_bases.func result. 344 extern void *_Unwind_FindEnclosingFunction(void *pc); 345 346 // Mac OS X does not support text-rel and data-rel addressing so these functions 347 // are unimplemented 348 extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 349 LIBUNWIND_UNAVAIL; 350 extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context *context) 351 LIBUNWIND_UNAVAIL; 352 353 // Mac OS X 10.4 and 10.5 had implementations of these functions in 354 // libgcc_s.dylib, but they never worked. 355 /// These functions are no longer available on Mac OS X. 356 extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 357 void *db) LIBUNWIND_UNAVAIL; 358 extern void __register_frame_info(const void *fde, void *ob) 359 LIBUNWIND_UNAVAIL; 360 extern void __register_frame_info_table_bases(const void *fde, void *ob, 361 void *tb, void *db) 362 LIBUNWIND_UNAVAIL; 363 extern void __register_frame_info_table(const void *fde, void *ob) 364 LIBUNWIND_UNAVAIL; 365 extern void __register_frame_table(const void *fde) 366 LIBUNWIND_UNAVAIL; 367 extern void *__deregister_frame_info(const void *fde) 368 LIBUNWIND_UNAVAIL; 369 extern void *__deregister_frame_info_bases(const void *fde) 370 LIBUNWIND_UNAVAIL; 371 372 #ifdef __cplusplus 373 } 374 #endif 375 376 #endif // __UNWIND_H__ 377
