1 //===------------------------------- unwind.h -----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
9 // C++ ABI Level 1 ABI documented at:
10 // http://mentorembedded.github.io/cxx-abi/abi-eh.html
12 //===----------------------------------------------------------------------===//
17 #include <__libunwind_config.h>
22 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) && defined(_WIN32)
27 #if defined(__APPLE__)
28 #define LIBUNWIND_UNAVAIL __attribute__ (( unavailable ))
30 #define LIBUNWIND_UNAVAIL
36 _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
37 _URC_FATAL_PHASE2_ERROR = 2,
38 _URC_FATAL_PHASE1_ERROR = 3,
40 _URC_END_OF_STACK = 5,
41 _URC_HANDLER_FOUND = 6,
42 _URC_INSTALL_CONTEXT = 7,
43 _URC_CONTINUE_UNWIND = 8,
44 #if defined(_LIBUNWIND_ARM_EHABI)
47 } _Unwind_Reason_Code;
51 _UA_CLEANUP_PHASE = 2,
52 _UA_HANDLER_FRAME = 4,
54 _UA_END_OF_STACK = 16 // gcc extension to C++ ABI
57 typedef struct _Unwind_Context _Unwind_Context; // opaque
59 #if defined(_LIBUNWIND_ARM_EHABI)
60 typedef uint32_t _Unwind_State;
62 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0;
63 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1;
64 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2;
65 static const _Unwind_State _US_ACTION_MASK = 3;
66 /* Undocumented flag for force unwinding. */
67 static const _Unwind_State _US_FORCE_UNWIND = 8;
69 typedef uint32_t _Unwind_EHT_Header;
71 struct _Unwind_Control_Block;
72 typedef struct _Unwind_Control_Block _Unwind_Control_Block;
73 typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */
75 struct _Unwind_Control_Block {
76 uint64_t exception_class;
77 void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block*);
79 /* Unwinder cache, private fields for the unwinder's use */
81 uint32_t reserved1; /* init reserved1 to 0, then don't touch */
88 /* Propagation barrier cache (valid after phase 1): */
91 uint32_t bitpattern[5];
94 /* Cleanup cache (preserved over cleanup): */
96 uint32_t bitpattern[4];
99 /* Pr cache (for pr's benefit): */
101 uint32_t fnstart; /* function start address */
102 _Unwind_EHT_Header* ehtp; /* pointer to EHT entry header word */
107 long long int :0; /* Enforce the 8-byte alignment */
108 } __attribute__((__aligned__(8)));
110 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn)
111 (_Unwind_State state,
112 _Unwind_Exception* exceptionObject,
113 struct _Unwind_Context* context);
115 typedef _Unwind_Reason_Code (*__personality_routine)
116 (_Unwind_State state,
117 _Unwind_Exception* exceptionObject,
118 struct _Unwind_Context* context);
120 struct _Unwind_Context; // opaque
121 struct _Unwind_Exception; // forward declaration
122 typedef struct _Unwind_Exception _Unwind_Exception;
124 struct _Unwind_Exception {
125 uint64_t exception_class;
126 void (*exception_cleanup)(_Unwind_Reason_Code reason,
127 _Unwind_Exception *exc);
128 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
129 uintptr_t private_[6];
131 uintptr_t private_1; // non-zero means forced unwind
132 uintptr_t private_2; // holds sp that phase1 found for phase2 to use
134 #if __SIZEOF_POINTER__ == 4
135 // The implementation of _Unwind_Exception uses an attribute mode on the
136 // above fields which has the side effect of causing this whole struct to
137 // round up to 32 bytes in size (48 with SEH). To be more explicit, we add
138 // pad fields added for binary compatibility.
139 uint32_t reserved[3];
141 // The Itanium ABI requires that _Unwind_Exception objects are "double-word
142 // aligned". GCC has interpreted this to mean "use the maximum useful
143 // alignment for the target"; so do we.
144 } __attribute__((__aligned__));
146 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn)
148 _Unwind_Action actions,
149 uint64_t exceptionClass,
150 _Unwind_Exception* exceptionObject,
151 struct _Unwind_Context* context,
152 void* stop_parameter );
154 typedef _Unwind_Reason_Code (*__personality_routine)
156 _Unwind_Action actions,
157 uint64_t exceptionClass,
158 _Unwind_Exception* exceptionObject,
159 struct _Unwind_Context* context);
167 // The following are the base functions documented by the C++ ABI
169 #ifdef __USING_SJLJ_EXCEPTIONS__
170 extern _Unwind_Reason_Code
171 _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object);
172 extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object);
174 extern _Unwind_Reason_Code
175 _Unwind_RaiseException(_Unwind_Exception *exception_object);
176 extern void _Unwind_Resume(_Unwind_Exception *exception_object);
178 extern void _Unwind_DeleteException(_Unwind_Exception *exception_object);
180 #if defined(_LIBUNWIND_ARM_EHABI)
182 _UVRSC_CORE = 0, /* integer register */
183 _UVRSC_VFP = 1, /* vfp */
184 _UVRSC_WMMXD = 3, /* Intel WMMX data register */
185 _UVRSC_WMMXC = 4 /* Intel WMMX control register */
186 } _Unwind_VRS_RegClass;
194 } _Unwind_VRS_DataRepresentation;
198 _UVRSR_NOT_IMPLEMENTED = 1,
200 } _Unwind_VRS_Result;
202 extern void _Unwind_Complete(_Unwind_Exception* exception_object);
204 extern _Unwind_VRS_Result
205 _Unwind_VRS_Get(_Unwind_Context *context, _Unwind_VRS_RegClass regclass,
206 uint32_t regno, _Unwind_VRS_DataRepresentation representation,
209 extern _Unwind_VRS_Result
210 _Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass,
211 uint32_t regno, _Unwind_VRS_DataRepresentation representation,
214 extern _Unwind_VRS_Result
215 _Unwind_VRS_Pop(_Unwind_Context *context, _Unwind_VRS_RegClass regclass,
216 uint32_t discriminator,
217 _Unwind_VRS_DataRepresentation representation);
220 #if !defined(_LIBUNWIND_ARM_EHABI)
222 extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index);
223 extern void _Unwind_SetGR(struct _Unwind_Context *context, int index,
224 uintptr_t new_value);
225 extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context);
226 extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value);
228 #else // defined(_LIBUNWIND_ARM_EHABI)
230 #if defined(_LIBUNWIND_UNWIND_LEVEL1_EXTERNAL_LINKAGE)
231 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 extern
233 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 static __inline__
236 // These are de facto helper functions for ARM, which delegate the function
237 // calls to _Unwind_VRS_Get/Set(). These are not a part of ARM EHABI
238 // specification, thus these function MUST be inlined. Please don't replace
239 // these with the "extern" function declaration; otherwise, the program
240 // including this <unwind.h> header won't be ABI compatible and will result in
241 // link error when we are linking the program with libgcc.
243 _LIBUNWIND_EXPORT_UNWIND_LEVEL1
244 uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index) {
246 _Unwind_VRS_Get(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value);
250 _LIBUNWIND_EXPORT_UNWIND_LEVEL1
251 void _Unwind_SetGR(struct _Unwind_Context *context, int index,
253 _Unwind_VRS_Set(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value);
256 _LIBUNWIND_EXPORT_UNWIND_LEVEL1
257 uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
258 // remove the thumb-bit before returning
259 return _Unwind_GetGR(context, 15) & (~(uintptr_t)0x1);
262 _LIBUNWIND_EXPORT_UNWIND_LEVEL1
263 void _Unwind_SetIP(struct _Unwind_Context *context, uintptr_t value) {
264 uintptr_t thumb_bit = _Unwind_GetGR(context, 15) & ((uintptr_t)0x1);
265 _Unwind_SetGR(context, 15, value | thumb_bit);
267 #endif // defined(_LIBUNWIND_ARM_EHABI)
269 extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context);
271 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context);
272 #ifdef __USING_SJLJ_EXCEPTIONS__
273 extern _Unwind_Reason_Code
274 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object,
275 _Unwind_Stop_Fn stop, void *stop_parameter);
277 extern _Unwind_Reason_Code
278 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
279 _Unwind_Stop_Fn stop, void *stop_parameter);
282 #ifdef __USING_SJLJ_EXCEPTIONS__
283 typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t;
284 extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc);
285 extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc);
289 // The following are semi-suppoted extensions to the C++ ABI
293 // called by __cxa_rethrow().
295 #ifdef __USING_SJLJ_EXCEPTIONS__
296 extern _Unwind_Reason_Code
297 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object);
299 extern _Unwind_Reason_Code
300 _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object);
303 // _Unwind_Backtrace() is a gcc extension that walks the stack and calls the
304 // _Unwind_Trace_Fn once per frame until it reaches the bottom of the stack
305 // or the _Unwind_Trace_Fn function returns something other than _URC_NO_REASON.
306 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *,
308 extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *);
310 // _Unwind_GetCFA is a gcc extension that can be called from within a
311 // personality handler to get the CFA (stack pointer before call) of
313 extern uintptr_t _Unwind_GetCFA(struct _Unwind_Context *);
316 // _Unwind_GetIPInfo is a gcc extension that can be called from within a
317 // personality handler. Similar to _Unwind_GetIP() but also returns in
318 // *ipBefore a non-zero value if the instruction pointer is at or before the
319 // instruction causing the unwind. Normally, in a function call, the IP returned
320 // is the return address which is after the call instruction and may be past the
321 // end of the function containing the call instruction.
322 extern uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
326 // __register_frame() is used with dynamically generated code to register the
327 // FDE for a generated (JIT) code. The FDE must use pc-rel addressing to point
328 // to its function and optional LSDA.
329 // __register_frame() has existed in all versions of Mac OS X, but in 10.4 and
330 // 10.5 it was buggy and did not actually register the FDE with the unwinder.
331 // In 10.6 and later it does register properly.
332 extern void __register_frame(const void *fde);
333 extern void __deregister_frame(const void *fde);
335 // _Unwind_Find_FDE() will locate the FDE if the pc is in some function that has
336 // an associated FDE. Note, Mac OS X 10.6 and later, introduces "compact unwind
337 // info" which the runtime uses in preference to DWARF unwind info. This
338 // function will only work if the target function has an FDE but no compact
340 struct dwarf_eh_bases {
345 extern const void *_Unwind_Find_FDE(const void *pc, struct dwarf_eh_bases *);
348 // This function attempts to find the start (address of first instruction) of
349 // a function given an address inside the function. It only works if the
350 // function has an FDE (DWARF unwind info).
351 // This function is unimplemented on Mac OS X 10.6 and later. Instead, use
352 // _Unwind_Find_FDE() and look at the dwarf_eh_bases.func result.
353 extern void *_Unwind_FindEnclosingFunction(void *pc);
355 // Mac OS X does not support text-rel and data-rel addressing so these functions
357 extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context)
359 extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context *context)
362 // Mac OS X 10.4 and 10.5 had implementations of these functions in
363 // libgcc_s.dylib, but they never worked.
364 /// These functions are no longer available on Mac OS X.
365 extern void __register_frame_info_bases(const void *fde, void *ob, void *tb,
366 void *db) LIBUNWIND_UNAVAIL;
367 extern void __register_frame_info(const void *fde, void *ob)
369 extern void __register_frame_info_table_bases(const void *fde, void *ob,
372 extern void __register_frame_info_table(const void *fde, void *ob)
374 extern void __register_frame_table(const void *fde)
376 extern void *__deregister_frame_info(const void *fde)
378 extern void *__deregister_frame_info_bases(const void *fde)
381 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
383 typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD;
384 typedef struct _CONTEXT CONTEXT;
385 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT;
386 #elif !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000
387 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT;
389 // This is the common wrapper for GCC-style personality functions with SEH.
390 extern EXCEPTION_DISPOSITION _GCC_specific_handler(EXCEPTION_RECORD *exc,
393 DISPATCHER_CONTEXT *disp,
394 __personality_routine pers);
401 #endif // __UNWIND_H__