1/*===---- unwind.h - Stack unwinding ----------------------------------------===
2 *
3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 * See https://llvm.org/LICENSE.txt for license information.
5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 *
7 *===-----------------------------------------------------------------------===
8 */
9
10/* See "Data Definitions for libgcc_s" in the Linux Standard Base.*/
11
12#ifndef __CLANG_UNWIND_H
13#define __CLANG_UNWIND_H
14
15#if defined(__APPLE__) && __has_include_next(<unwind.h>)
16/* Darwin (from 11.x on) provide an unwind.h. If that's available,
17 * use it. libunwind wraps some of its definitions in #ifdef _GNU_SOURCE,
18 * so define that around the include.*/
19# ifndef _GNU_SOURCE
20#  define _SHOULD_UNDEFINE_GNU_SOURCE
21#  define _GNU_SOURCE
22# endif
23// libunwind's unwind.h reflects the current visibility.  However, Mozilla
24// builds with -fvisibility=hidden and relies on gcc's unwind.h to reset the
25// visibility to default and export its contents.  gcc also allows users to
26// override its override by #defining HIDE_EXPORTS (but note, this only obeys
27// the user's -fvisibility setting; it doesn't hide any exports on its own).  We
28// imitate gcc's header here:
29# ifdef HIDE_EXPORTS
30#  include_next <unwind.h>
31# else
32#  pragma GCC visibility push(default)
33#  include_next <unwind.h>
34#  pragma GCC visibility pop
35# endif
36# ifdef _SHOULD_UNDEFINE_GNU_SOURCE
37#  undef _GNU_SOURCE
38#  undef _SHOULD_UNDEFINE_GNU_SOURCE
39# endif
40#else
41
42#include <stdint.h>
43
44#ifdef __cplusplus
45extern "C" {
46#endif
47
48/* It is a bit strange for a header to play with the visibility of the
49   symbols it declares, but this matches gcc's behavior and some programs
50   depend on it */
51#ifndef HIDE_EXPORTS
52#pragma GCC visibility push(default)
53#endif
54
55typedef uintptr_t _Unwind_Word __attribute__((__mode__(__unwind_word__)));
56typedef intptr_t _Unwind_Sword __attribute__((__mode__(__unwind_word__)));
57typedef uintptr_t _Unwind_Ptr;
58typedef uintptr_t _Unwind_Internal_Ptr;
59typedef uint64_t _Unwind_Exception_Class;
60
61typedef intptr_t _sleb128_t;
62typedef uintptr_t _uleb128_t;
63
64struct _Unwind_Context;
65#if defined(__arm__) && !(defined(__USING_SJLJ_EXCEPTIONS__) || \
66                          defined(__ARM_DWARF_EH__) || defined(__SEH__))
67struct _Unwind_Control_Block;
68typedef struct _Unwind_Control_Block _Unwind_Control_Block;
69#define _Unwind_Exception _Unwind_Control_Block /* Alias */
70#else
71struct _Unwind_Exception;
72typedef struct _Unwind_Exception _Unwind_Exception;
73#endif
74typedef enum {
75  _URC_NO_REASON = 0,
76#if defined(__arm__) && !defined(__USING_SJLJ_EXCEPTIONS__) && \
77    !defined(__ARM_DWARF_EH__) && !defined(__SEH__)
78  _URC_OK = 0, /* used by ARM EHABI */
79#endif
80  _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
81
82  _URC_FATAL_PHASE2_ERROR = 2,
83  _URC_FATAL_PHASE1_ERROR = 3,
84  _URC_NORMAL_STOP = 4,
85
86  _URC_END_OF_STACK = 5,
87  _URC_HANDLER_FOUND = 6,
88  _URC_INSTALL_CONTEXT = 7,
89  _URC_CONTINUE_UNWIND = 8,
90#if defined(__arm__) && !defined(__USING_SJLJ_EXCEPTIONS__) && \
91    !defined(__ARM_DWARF_EH__) && !defined(__SEH__)
92  _URC_FAILURE = 9 /* used by ARM EHABI */
93#endif
94} _Unwind_Reason_Code;
95
96typedef enum {
97  _UA_SEARCH_PHASE = 1,
98  _UA_CLEANUP_PHASE = 2,
99
100  _UA_HANDLER_FRAME = 4,
101  _UA_FORCE_UNWIND = 8,
102  _UA_END_OF_STACK = 16 /* gcc extension to C++ ABI */
103} _Unwind_Action;
104
105typedef void (*_Unwind_Exception_Cleanup_Fn)(_Unwind_Reason_Code,
106                                             _Unwind_Exception *);
107
108#if defined(__arm__) && !(defined(__USING_SJLJ_EXCEPTIONS__) || \
109                          defined(__ARM_DWARF_EH__) || defined(__SEH__))
110typedef struct _Unwind_Control_Block _Unwind_Control_Block;
111typedef uint32_t _Unwind_EHT_Header;
112
113struct _Unwind_Control_Block {
114  uint64_t exception_class;
115  void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *);
116  /* unwinder cache (private fields for the unwinder's use) */
117  struct {
118    uint32_t reserved1; /* forced unwind stop function, 0 if not forced */
119    uint32_t reserved2; /* personality routine */
120    uint32_t reserved3; /* callsite */
121    uint32_t reserved4; /* forced unwind stop argument */
122    uint32_t reserved5;
123  } unwinder_cache;
124  /* propagation barrier cache (valid after phase 1) */
125  struct {
126    uint32_t sp;
127    uint32_t bitpattern[5];
128  } barrier_cache;
129  /* cleanup cache (preserved over cleanup) */
130  struct {
131    uint32_t bitpattern[4];
132  } cleanup_cache;
133  /* personality cache (for personality's benefit) */
134  struct {
135    uint32_t fnstart;         /* function start address */
136    _Unwind_EHT_Header *ehtp; /* pointer to EHT entry header word */
137    uint32_t additional;      /* additional data */
138    uint32_t reserved1;
139  } pr_cache;
140  long long int : 0; /* force alignment of next item to 8-byte boundary */
141} __attribute__((__aligned__(8)));
142#else
143struct _Unwind_Exception {
144  _Unwind_Exception_Class exception_class;
145  _Unwind_Exception_Cleanup_Fn exception_cleanup;
146#if !defined (__USING_SJLJ_EXCEPTIONS__) && defined (__SEH__)
147  _Unwind_Word private_[6];
148#else
149  _Unwind_Word private_1;
150  _Unwind_Word private_2;
151#endif
152  /* The Itanium ABI requires that _Unwind_Exception objects are "double-word
153   * aligned".  GCC has interpreted this to mean "use the maximum useful
154   * alignment for the target"; so do we. */
155} __attribute__((__aligned__));
156#endif
157
158typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn)(int, _Unwind_Action,
159                                               _Unwind_Exception_Class,
160                                               _Unwind_Exception *,
161                                               struct _Unwind_Context *,
162                                               void *);
163
164typedef _Unwind_Reason_Code (*_Unwind_Personality_Fn)(int, _Unwind_Action,
165                                                      _Unwind_Exception_Class,
166                                                      _Unwind_Exception *,
167                                                      struct _Unwind_Context *);
168typedef _Unwind_Personality_Fn __personality_routine;
169
170typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *,
171                                                void *);
172
173#if defined(__arm__) && !(defined(__USING_SJLJ_EXCEPTIONS__) ||                \
174                          defined(__ARM_DWARF_EH__) || defined(__SEH__))
175typedef enum {
176  _UVRSC_CORE = 0,        /* integer register */
177  _UVRSC_VFP = 1,         /* vfp */
178  _UVRSC_WMMXD = 3,       /* Intel WMMX data register */
179  _UVRSC_WMMXC = 4,       /* Intel WMMX control register */
180  _UVRSC_PSEUDO = 5       /* Special purpose pseudo register */
181} _Unwind_VRS_RegClass;
182
183typedef enum {
184  _UVRSD_UINT32 = 0,
185  _UVRSD_VFPX = 1,
186  _UVRSD_UINT64 = 3,
187  _UVRSD_FLOAT = 4,
188  _UVRSD_DOUBLE = 5
189} _Unwind_VRS_DataRepresentation;
190
191typedef enum {
192  _UVRSR_OK = 0,
193  _UVRSR_NOT_IMPLEMENTED = 1,
194  _UVRSR_FAILED = 2
195} _Unwind_VRS_Result;
196
197typedef uint32_t _Unwind_State;
198#define _US_VIRTUAL_UNWIND_FRAME  ((_Unwind_State)0)
199#define _US_UNWIND_FRAME_STARTING ((_Unwind_State)1)
200#define _US_UNWIND_FRAME_RESUME   ((_Unwind_State)2)
201#define _US_ACTION_MASK           ((_Unwind_State)3)
202#define _US_FORCE_UNWIND          ((_Unwind_State)8)
203
204_Unwind_VRS_Result _Unwind_VRS_Get(struct _Unwind_Context *__context,
205  _Unwind_VRS_RegClass __regclass,
206  uint32_t __regno,
207  _Unwind_VRS_DataRepresentation __representation,
208  void *__valuep);
209
210_Unwind_VRS_Result _Unwind_VRS_Set(struct _Unwind_Context *__context,
211  _Unwind_VRS_RegClass __regclass,
212  uint32_t __regno,
213  _Unwind_VRS_DataRepresentation __representation,
214  void *__valuep);
215
216static __inline__
217_Unwind_Word _Unwind_GetGR(struct _Unwind_Context *__context, int __index) {
218  _Unwind_Word __value;
219  _Unwind_VRS_Get(__context, _UVRSC_CORE, __index, _UVRSD_UINT32, &__value);
220  return __value;
221}
222
223static __inline__
224void _Unwind_SetGR(struct _Unwind_Context *__context, int __index,
225                   _Unwind_Word __value) {
226  _Unwind_VRS_Set(__context, _UVRSC_CORE, __index, _UVRSD_UINT32, &__value);
227}
228
229static __inline__
230_Unwind_Word _Unwind_GetIP(struct _Unwind_Context *__context) {
231  _Unwind_Word __ip = _Unwind_GetGR(__context, 15);
232  return __ip & ~(_Unwind_Word)(0x1); /* Remove thumb mode bit. */
233}
234
235static __inline__
236void _Unwind_SetIP(struct _Unwind_Context *__context, _Unwind_Word __value) {
237  _Unwind_Word __thumb_mode_bit = _Unwind_GetGR(__context, 15) & 0x1;
238  _Unwind_SetGR(__context, 15, __value | __thumb_mode_bit);
239}
240#else
241_Unwind_Word _Unwind_GetGR(struct _Unwind_Context *, int);
242void _Unwind_SetGR(struct _Unwind_Context *, int, _Unwind_Word);
243
244_Unwind_Word _Unwind_GetIP(struct _Unwind_Context *);
245void _Unwind_SetIP(struct _Unwind_Context *, _Unwind_Word);
246#endif
247
248
249_Unwind_Word _Unwind_GetIPInfo(struct _Unwind_Context *, int *);
250
251_Unwind_Word _Unwind_GetCFA(struct _Unwind_Context *);
252
253_Unwind_Word _Unwind_GetBSP(struct _Unwind_Context *);
254
255void *_Unwind_GetLanguageSpecificData(struct _Unwind_Context *);
256
257_Unwind_Ptr _Unwind_GetRegionStart(struct _Unwind_Context *);
258
259/* DWARF EH functions; currently not available on Darwin/ARM */
260#if !defined(__APPLE__) || !defined(__arm__)
261_Unwind_Reason_Code _Unwind_RaiseException(_Unwind_Exception *);
262_Unwind_Reason_Code _Unwind_ForcedUnwind(_Unwind_Exception *, _Unwind_Stop_Fn,
263                                         void *);
264void _Unwind_DeleteException(_Unwind_Exception *);
265void _Unwind_Resume(_Unwind_Exception *);
266_Unwind_Reason_Code _Unwind_Resume_or_Rethrow(_Unwind_Exception *);
267
268#endif
269
270_Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *);
271
272/* setjmp(3)/longjmp(3) stuff */
273typedef struct SjLj_Function_Context *_Unwind_FunctionContext_t;
274
275void _Unwind_SjLj_Register(_Unwind_FunctionContext_t);
276void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t);
277_Unwind_Reason_Code _Unwind_SjLj_RaiseException(_Unwind_Exception *);
278_Unwind_Reason_Code _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *,
279                                              _Unwind_Stop_Fn, void *);
280void _Unwind_SjLj_Resume(_Unwind_Exception *);
281_Unwind_Reason_Code _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *);
282
283void *_Unwind_FindEnclosingFunction(void *);
284
285#ifdef __APPLE__
286
287_Unwind_Ptr _Unwind_GetDataRelBase(struct _Unwind_Context *)
288    __attribute__((__unavailable__));
289_Unwind_Ptr _Unwind_GetTextRelBase(struct _Unwind_Context *)
290    __attribute__((__unavailable__));
291
292/* Darwin-specific functions */
293void __register_frame(const void *);
294void __deregister_frame(const void *);
295
296struct dwarf_eh_bases {
297  uintptr_t tbase;
298  uintptr_t dbase;
299  uintptr_t func;
300};
301void *_Unwind_Find_FDE(const void *, struct dwarf_eh_bases *);
302
303void __register_frame_info_bases(const void *, void *, void *, void *)
304  __attribute__((__unavailable__));
305void __register_frame_info(const void *, void *) __attribute__((__unavailable__));
306void __register_frame_info_table_bases(const void *, void*, void *, void *)
307  __attribute__((__unavailable__));
308void __register_frame_info_table(const void *, void *)
309  __attribute__((__unavailable__));
310void __register_frame_table(const void *) __attribute__((__unavailable__));
311void __deregister_frame_info(const void *) __attribute__((__unavailable__));
312void __deregister_frame_info_bases(const void *)__attribute__((__unavailable__));
313
314#else
315
316_Unwind_Ptr _Unwind_GetDataRelBase(struct _Unwind_Context *);
317_Unwind_Ptr _Unwind_GetTextRelBase(struct _Unwind_Context *);
318
319#endif
320
321
322#ifndef HIDE_EXPORTS
323#pragma GCC visibility pop
324#endif
325
326#ifdef __cplusplus
327}
328#endif
329
330#endif
331
332#endif /* __CLANG_UNWIND_H */
333