Unwind_AppleExtras.cpp revision 952df57e2c437ad013511e445a2b8bffa77bf9ca 
1//===--------------------- Unwind_AppleExtras.cpp -------------------------===//
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//===----------------------------------------------------------------------===//
10
11#include "config.h"
12#include "DwarfParser.hpp"
13#include "unwind_ext.h"
14
15
16// private keymgr stuff
17#define KEYMGR_GCC3_DW2_OBJ_LIST 302
18extern "C" {
19 extern void _keymgr_set_and_unlock_processwide_ptr(int key, void *ptr);
20 extern void *_keymgr_get_and_lock_processwide_ptr(int key);
21}
22
23// undocumented libgcc "struct object"
24struct libgcc_object {
25  void          *start;
26  void          *unused1;
27  void          *unused2;
28  void          *fde;
29  unsigned long  encoding;
30  void          *fde_end;
31  libgcc_object *next;
32};
33
34// undocumented libgcc "struct km_object_info" referenced by
35// KEYMGR_GCC3_DW2_OBJ_LIST
36struct libgcc_object_info {
37  libgcc_object   *seen_objects;
38  libgcc_object   *unseen_objects;
39  unsigned         spare[2];
40};
41
42
43// static linker symbols to prevent wrong two level namespace for _Unwind symbols
44#if __arm__
45   #define NOT_HERE_BEFORE_5_0(sym)     \
46       extern const char sym##_tmp30 __asm("$ld$hide$os3.0$_" #sym ); \
47       __attribute__((visibility("default"))) const char sym##_tmp30 = 0; \
48       extern const char sym##_tmp31 __asm("$ld$hide$os3.1$_" #sym ); \
49          __attribute__((visibility("default"))) const char sym##_tmp31 = 0; \
50       extern const char sym##_tmp32 __asm("$ld$hide$os3.2$_" #sym );\
51           __attribute__((visibility("default"))) const char sym##_tmp32 = 0; \
52       extern const char sym##_tmp40 __asm("$ld$hide$os4.0$_" #sym ); \
53          __attribute__((visibility("default"))) const char sym##_tmp40 = 0; \
54       extern const char sym##_tmp41 __asm("$ld$hide$os4.1$_" #sym ); \
55          __attribute__((visibility("default"))) const char sym##_tmp41 = 0; \
56       extern const char sym##_tmp42 __asm("$ld$hide$os4.2$_" #sym ); \
57          __attribute__((visibility("default"))) const char sym##_tmp42 = 0; \
58       extern const char sym##_tmp43 __asm("$ld$hide$os4.3$_" #sym ); \
59          __attribute__((visibility("default"))) const char sym##_tmp43 = 0;
60#elif __arm64__
61  #define NOT_HERE_BEFORE_10_6(sym)
62  #define NEVER_HERE(sym)
63#else
64  #define NOT_HERE_BEFORE_10_6(sym) \
65    extern const char sym##_tmp4 __asm("$ld$hide$os10.4$_" #sym ); \
66          __attribute__((visibility("default"))) const char sym##_tmp4 = 0; \
67    extern const char sym##_tmp5 __asm("$ld$hide$os10.5$_" #sym ); \
68          __attribute__((visibility("default"))) const char sym##_tmp5 = 0;
69  #define NEVER_HERE(sym) \
70    extern const char sym##_tmp4 __asm("$ld$hide$os10.4$_" #sym ); \
71          __attribute__((visibility("default"))) const char sym##_tmp4 = 0; \
72    extern const char sym##_tmp5 __asm("$ld$hide$os10.5$_" #sym ); \
73          __attribute__((visibility("default"))) const char sym##_tmp5 = 0; \
74    extern const char sym##_tmp6 __asm("$ld$hide$os10.6$_" #sym ); \
75          __attribute__((visibility("default"))) const char sym##_tmp6 = 0;
76#endif
77
78
79#if _LIBUNWIND_BUILD_ZERO_COST_APIS
80
81//
82// symbols in libSystem.dylib in 10.6 and later, but are in libgcc_s.dylib in
83// earlier versions
84//
85NOT_HERE_BEFORE_10_6(_Unwind_DeleteException)
86NOT_HERE_BEFORE_10_6(_Unwind_Find_FDE)
87NOT_HERE_BEFORE_10_6(_Unwind_ForcedUnwind)
88NOT_HERE_BEFORE_10_6(_Unwind_GetGR)
89NOT_HERE_BEFORE_10_6(_Unwind_GetIP)
90NOT_HERE_BEFORE_10_6(_Unwind_GetLanguageSpecificData)
91NOT_HERE_BEFORE_10_6(_Unwind_GetRegionStart)
92NOT_HERE_BEFORE_10_6(_Unwind_RaiseException)
93NOT_HERE_BEFORE_10_6(_Unwind_Resume)
94NOT_HERE_BEFORE_10_6(_Unwind_SetGR)
95NOT_HERE_BEFORE_10_6(_Unwind_SetIP)
96NOT_HERE_BEFORE_10_6(_Unwind_Backtrace)
97NOT_HERE_BEFORE_10_6(_Unwind_FindEnclosingFunction)
98NOT_HERE_BEFORE_10_6(_Unwind_GetCFA)
99NOT_HERE_BEFORE_10_6(_Unwind_GetDataRelBase)
100NOT_HERE_BEFORE_10_6(_Unwind_GetTextRelBase)
101NOT_HERE_BEFORE_10_6(_Unwind_Resume_or_Rethrow)
102NOT_HERE_BEFORE_10_6(_Unwind_GetIPInfo)
103NOT_HERE_BEFORE_10_6(__register_frame)
104NOT_HERE_BEFORE_10_6(__deregister_frame)
105
106//
107// symbols in libSystem.dylib for compatibility, but we don't want any new code
108// using them
109//
110NEVER_HERE(__register_frame_info_bases)
111NEVER_HERE(__register_frame_info)
112NEVER_HERE(__register_frame_info_table_bases)
113NEVER_HERE(__register_frame_info_table)
114NEVER_HERE(__register_frame_table)
115NEVER_HERE(__deregister_frame_info)
116NEVER_HERE(__deregister_frame_info_bases)
117
118#endif // _LIBUNWIND_BUILD_ZERO_COST_APIS
119
120
121
122
123#if _LIBUNWIND_BUILD_SJLJ_APIS
124//
125// symbols in libSystem.dylib in iOS 5.0 and later, but are in libgcc_s.dylib in
126// earlier versions
127//
128NOT_HERE_BEFORE_5_0(_Unwind_GetLanguageSpecificData)
129NOT_HERE_BEFORE_5_0(_Unwind_GetRegionStart)
130NOT_HERE_BEFORE_5_0(_Unwind_GetIP)
131NOT_HERE_BEFORE_5_0(_Unwind_SetGR)
132NOT_HERE_BEFORE_5_0(_Unwind_SetIP)
133NOT_HERE_BEFORE_5_0(_Unwind_DeleteException)
134NOT_HERE_BEFORE_5_0(_Unwind_SjLj_Register)
135NOT_HERE_BEFORE_5_0(_Unwind_GetGR)
136NOT_HERE_BEFORE_5_0(_Unwind_GetIPInfo)
137NOT_HERE_BEFORE_5_0(_Unwind_GetCFA)
138NOT_HERE_BEFORE_5_0(_Unwind_SjLj_Resume)
139NOT_HERE_BEFORE_5_0(_Unwind_SjLj_RaiseException)
140NOT_HERE_BEFORE_5_0(_Unwind_SjLj_Resume_or_Rethrow)
141NOT_HERE_BEFORE_5_0(_Unwind_SjLj_Unregister)
142
143#endif // _LIBUNWIND_BUILD_SJLJ_APIS
144
145
146namespace libunwind {
147
148_LIBUNWIND_HIDDEN
149bool checkKeyMgrRegisteredFDEs(uintptr_t pc, void *&fde) {
150#if __MAC_OS_X_VERSION_MIN_REQUIRED
151  // lastly check for old style keymgr registration of dynamically generated
152  // FDEs acquire exclusive access to libgcc_object_info
153  libgcc_object_info *head = (libgcc_object_info *)
154                _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
155  if (head != NULL) {
156    // look at each FDE in keymgr
157    for (libgcc_object *ob = head->unseen_objects; ob != NULL; ob = ob->next) {
158      CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
159      CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
160      const char *msg = CFI_Parser<LocalAddressSpace>::decodeFDE(
161                                      LocalAddressSpace::sThisAddressSpace,
162                                      (uintptr_t)ob->fde, &fdeInfo, &cieInfo);
163      if (msg == NULL) {
164        // Check if this FDE is for a function that includes the pc
165        if ((fdeInfo.pcStart <= pc) && (pc < fdeInfo.pcEnd)) {
166          fde = (void*)fdeInfo.pcStart;
167          _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST,
168                                                 head);
169          return true;
170        }
171      }
172    }
173  }
174  // release libgcc_object_info
175  _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, head);
176#else
177  (void)pc;
178  (void)fde;
179#endif
180  return false;
181}
182
183}
184
185
186#if !FOR_DYLD && _LIBUNWIND_BUILD_SJLJ_APIS
187
188#include <System/pthread_machdep.h>
189
190// Accessors to get get/set linked list of frames for sjlj based execeptions.
191_LIBUNWIND_HIDDEN
192struct _Unwind_FunctionContext *__Unwind_SjLj_GetTopOfFunctionStack() {
193  return (struct _Unwind_FunctionContext *)
194    _pthread_getspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key);
195}
196
197_LIBUNWIND_HIDDEN
198void __Unwind_SjLj_SetTopOfFunctionStack(struct _Unwind_FunctionContext *fc) {
199  _pthread_setspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key, fc);
200}
201#endif
202
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204
205
206