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