1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2002-2005 Hewlett-Packard Co
3 Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4
5 Modified for x86_64 by Max Asbock <masbock@us.ibm.com>
6
7 This file is part of libunwind.
8
9 Permission is hereby granted, free of charge, to any person obtaining
10 a copy of this software and associated documentation files (the
11 "Software"), to deal in the Software without restriction, including
12 without limitation the rights to use, copy, modify, merge, publish,
13 distribute, sublicense, and/or sell copies of the Software, and to
14 permit persons to whom the Software is furnished to do so, subject to
15 the following conditions:
16
17 The above copyright notice and this permission notice shall be
18 included in all copies or substantial portions of the Software.
19
20 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
24 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
25 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
26 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
27
28 #ifndef X86_64_LIBUNWIND_I_H
29 #define X86_64_LIBUNWIND_I_H
30
31 /* Target-dependent definitions that are internal to libunwind but need
32 to be shared with target-independent code. */
33
34 #include <stdint.h>
35 #include <stdlib.h>
36 #include <stdatomic.h>
37 #include <libunwind.h>
38
39 #include "elf64.h"
40 #include "mempool.h"
41 #include "dwarf.h"
42
43 typedef enum
44 {
45 UNW_X86_64_FRAME_ALIGNED = -3, /* frame stack pointer aligned */
46 UNW_X86_64_FRAME_STANDARD = -2, /* regular rbp, rsp +/- offset */
47 UNW_X86_64_FRAME_SIGRETURN = -1, /* special sigreturn frame */
48 UNW_X86_64_FRAME_OTHER = 0, /* not cacheable (special or unrecognised) */
49 UNW_X86_64_FRAME_GUESSED = 1 /* guessed it was regular, but not known */
50 }
51 unw_tdep_frame_type_t;
52
53 typedef struct
54 {
55 uint64_t virtual_address;
56 int64_t frame_type : 3; /* unw_tdep_frame_type_t classification */
57 int64_t last_frame : 1; /* non-zero if last frame in chain */
58 int64_t cfa_reg_rsp : 1; /* cfa dwarf base register is rsp vs. rbp */
59 int64_t cfa_reg_offset : 29; /* cfa is at this offset from base register value */
60 int64_t rbp_cfa_offset : 15; /* rbp saved at this offset from cfa (-1 = not saved) */
61 int64_t rsp_cfa_offset : 15; /* rsp saved at this offset from cfa (-1 = not saved) */
62 }
63 unw_tdep_frame_t;
64
65 struct unw_addr_space
66 {
67 struct unw_accessors acc;
68 unw_caching_policy_t caching_policy;
69 _Atomic uint32_t cache_generation;
70 unw_word_t dyn_generation; /* see dyn-common.h */
71 unw_word_t dyn_info_list_addr; /* (cached) dyn_info_list_addr */
72 struct dwarf_rs_cache global_cache;
73 struct unw_debug_frame_list *debug_frames;
74 };
75
76 struct cursor
77 {
78 struct dwarf_cursor dwarf; /* must be first */
79
80 unw_tdep_frame_t frame_info; /* quick tracing assist info */
81
82 /* Format of sigcontext structure and address at which it is
83 stored: */
84 enum
85 {
86 X86_64_SCF_NONE, /* no signal frame encountered */
87 X86_64_SCF_LINUX_RT_SIGFRAME, /* Linux ucontext_t */
88 X86_64_SCF_FREEBSD_SIGFRAME, /* FreeBSD signal frame */
89 X86_64_SCF_FREEBSD_SYSCALL, /* FreeBSD syscall */
90 X86_64_SCF_SOLARIS_SIGFRAME, /* illumos/Solaris signal frame */
91 }
92 sigcontext_format;
93 unw_word_t sigcontext_addr;
94 };
95
96 #define AS_ARG_UCONTEXT_MASK ~0x1UL
97 #define AS_ARG_VALIDATE_MASK 0x1UL
98
99 #define AS_ARG_GET_UC_PTR(arg) \
100 ((ucontext_t *) ((uintptr_t) arg & AS_ARG_UCONTEXT_MASK))
101 #define AS_ARG_GET_VALIDATE(arg) \
102 ((int) ((uintptr_t) arg & AS_ARG_VALIDATE_MASK))
103
104 static inline ucontext_t *
dwarf_get_uc(const struct dwarf_cursor * cursor)105 dwarf_get_uc(const struct dwarf_cursor *cursor)
106 {
107 assert(cursor->as == unw_local_addr_space);
108 return AS_ARG_GET_UC_PTR(cursor->as_arg);
109 }
110
111 static inline int
dwarf_get_validate(const struct dwarf_cursor * cursor)112 dwarf_get_validate(const struct dwarf_cursor *cursor)
113 {
114 assert(cursor->as == unw_local_addr_space);
115 return AS_ARG_GET_VALIDATE(cursor->as_arg);
116 }
117
118 static inline void
dwarf_set_validate(const struct dwarf_cursor * cursor,const int validate)119 dwarf_set_validate(const struct dwarf_cursor *cursor, const int validate)
120 {
121 assert(cursor->as == unw_local_addr_space);
122 uintptr_t *packed_args = (uintptr_t *) &cursor->as_arg;
123 *packed_args |= (AS_ARG_VALIDATE_MASK & validate);
124 }
125
126 static inline void *
dwarf_build_as_arg(const ucontext_t * uc,const int validate)127 dwarf_build_as_arg(const ucontext_t *uc, const int validate) {
128 uintptr_t packed_args = (uintptr_t) uc;
129 assert((packed_args & AS_ARG_VALIDATE_MASK) == 0);
130 packed_args |= (AS_ARG_VALIDATE_MASK & validate);
131 return (void *) packed_args;
132 }
133
134 #define DWARF_GET_LOC(l) ((l).val)
135 # define DWARF_LOC_TYPE_MEM (0 << 0)
136 # define DWARF_LOC_TYPE_FP (1 << 0)
137 # define DWARF_LOC_TYPE_REG (1 << 1)
138 # define DWARF_LOC_TYPE_VAL (1 << 2)
139
140 # define DWARF_IS_REG_LOC(l) (((l).type & DWARF_LOC_TYPE_REG) != 0)
141 # define DWARF_IS_FP_LOC(l) (((l).type & DWARF_LOC_TYPE_FP) != 0)
142 # define DWARF_IS_MEM_LOC(l) ((l).type == DWARF_LOC_TYPE_MEM)
143 # define DWARF_IS_VAL_LOC(l) (((l).type & DWARF_LOC_TYPE_VAL) != 0)
144
145 # define DWARF_LOC(r, t) ((dwarf_loc_t) { .val = (r), .type = (t) })
146 # define DWARF_VAL_LOC(c,v) DWARF_LOC ((v), DWARF_LOC_TYPE_VAL)
147 # define DWARF_MEM_LOC(c,m) DWARF_LOC ((m), DWARF_LOC_TYPE_MEM)
148
149 #ifdef UNW_LOCAL_ONLY
150 # define DWARF_NULL_LOC DWARF_LOC (0, 0)
151 # define DWARF_IS_NULL_LOC(l) (DWARF_GET_LOC (l) == 0)
152 # define DWARF_REG_LOC(c,r) (DWARF_LOC((unw_word_t) \
153 x86_64_r_uc_addr(dwarf_get_uc(c), (r)), 0))
154 # define DWARF_FPREG_LOC(c,r) (DWARF_LOC((unw_word_t) \
155 x86_64_r_uc_addr(dwarf_get_uc(c), (r)), 0))
156
157 #else /* !UNW_LOCAL_ONLY */
158
159 # define DWARF_NULL_LOC DWARF_LOC (0, 0)
160
161 static inline int
dwarf_is_null_loc(dwarf_loc_t l)162 dwarf_is_null_loc(dwarf_loc_t l)
163 {
164 return l.val == 0 && l.type == 0;
165 }
166
167 # define DWARF_IS_NULL_LOC(l) dwarf_is_null_loc(l)
168 # define DWARF_REG_LOC(c,r) DWARF_LOC((r), DWARF_LOC_TYPE_REG)
169 # define DWARF_FPREG_LOC(c,r) DWARF_LOC((r), (DWARF_LOC_TYPE_REG \
170 | DWARF_LOC_TYPE_FP))
171
172 #endif /* !UNW_LOCAL_ONLY */
173
174 static inline int
dwarf_getfp(struct dwarf_cursor * c,dwarf_loc_t loc,unw_fpreg_t * val)175 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
176 {
177 if (DWARF_IS_NULL_LOC (loc))
178 return -UNW_EBADREG;
179
180 abort ();
181 }
182
183 static inline int
dwarf_putfp(struct dwarf_cursor * c,dwarf_loc_t loc,unw_fpreg_t val)184 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
185 {
186 if (DWARF_IS_NULL_LOC (loc))
187 return -UNW_EBADREG;
188
189 abort ();
190 }
191
192 static inline int
dwarf_get(struct dwarf_cursor * c,dwarf_loc_t loc,unw_word_t * val)193 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
194 {
195 if (DWARF_IS_NULL_LOC (loc))
196 return -UNW_EBADREG;
197
198 if (DWARF_IS_REG_LOC (loc))
199 return (*c->as->acc.access_reg) (c->as, DWARF_GET_LOC (loc), val,
200 0, c->as_arg);
201 if (DWARF_IS_MEM_LOC (loc))
202 return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), val,
203 0, c->as_arg);
204 assert(DWARF_IS_VAL_LOC (loc));
205 *val = DWARF_GET_LOC (loc);
206 return 0;
207 }
208
209 static inline int
dwarf_put(struct dwarf_cursor * c,dwarf_loc_t loc,unw_word_t val)210 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
211 {
212 assert(!DWARF_IS_VAL_LOC (loc));
213
214 if (DWARF_IS_NULL_LOC (loc))
215 return -UNW_EBADREG;
216
217 if (DWARF_IS_REG_LOC (loc))
218 return (*c->as->acc.access_reg) (c->as, DWARF_GET_LOC (loc), &val,
219 1, c->as_arg);
220 else
221 return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), &val,
222 1, c->as_arg);
223 }
224
225 #define tdep_getcontext_trace UNW_ARCH_OBJ(getcontext_trace)
226 #define tdep_init_done UNW_OBJ(init_done)
227 #define tdep_init_mem_validate UNW_OBJ(init_mem_validate)
228 #define tdep_init UNW_OBJ(init)
229 /* Platforms that support UNW_INFO_FORMAT_TABLE need to define
230 tdep_search_unwind_table. */
231 #define tdep_search_unwind_table dwarf_search_unwind_table
232 #define tdep_find_unwind_table dwarf_find_unwind_table
233 #define tdep_get_elf_image UNW_ARCH_OBJ(get_elf_image)
234 #define tdep_get_exe_image_path UNW_ARCH_OBJ(get_exe_image_path)
235 #define tdep_access_reg UNW_OBJ(access_reg)
236 #define tdep_access_fpreg UNW_OBJ(access_fpreg)
237 #if __linux__
238 # define tdep_fetch_frame UNW_OBJ(fetch_frame)
239 # define tdep_cache_frame UNW_OBJ(cache_frame)
240 # define tdep_reuse_frame UNW_OBJ(reuse_frame)
241 #else
242 # define tdep_fetch_frame(c,ip,n) do {} while(0)
243 # define tdep_cache_frame(c) 0
244 # define tdep_reuse_frame(c,frame) do {} while(0)
245 #endif
246 #define tdep_stash_frame UNW_OBJ(stash_frame)
247 #define tdep_trace UNW_OBJ(tdep_trace)
248 #define x86_64_r_uc_addr UNW_OBJ(r_uc_addr)
249
250 #ifdef UNW_LOCAL_ONLY
251 # define tdep_find_proc_info(c,ip,n) \
252 dwarf_find_proc_info((c)->as, (ip), &(c)->pi, (n), \
253 (c)->as_arg)
254 # define tdep_put_unwind_info(as,pi,arg) \
255 dwarf_put_unwind_info((as), (pi), (arg))
256 #else
257 # define tdep_find_proc_info(c,ip,n) \
258 (*(c)->as->acc.find_proc_info)((c)->as, (ip), &(c)->pi, (n), \
259 (c)->as_arg)
260 # define tdep_put_unwind_info(as,pi,arg) \
261 (*(as)->acc.put_unwind_info)((as), (pi), (arg))
262 #endif
263
264 #define tdep_get_as(c) ((c)->dwarf.as)
265 #define tdep_get_as_arg(c) ((c)->dwarf.as_arg)
266 #define tdep_get_ip(c) ((c)->dwarf.ip)
267 #define tdep_big_endian(as) 0
268
269 extern atomic_bool tdep_init_done;
270
271 extern void tdep_init (void);
272 extern void tdep_init_mem_validate (void);
273 extern int tdep_search_unwind_table (unw_addr_space_t as, unw_word_t ip,
274 unw_dyn_info_t *di, unw_proc_info_t *pi,
275 int need_unwind_info, void *arg);
276 extern void *x86_64_r_uc_addr (ucontext_t *uc, int reg);
277 extern int tdep_get_elf_image (struct elf_image *ei, pid_t pid, unw_word_t ip,
278 unsigned long *segbase, unsigned long *mapoff,
279 char *path, size_t pathlen);
280 extern void tdep_get_exe_image_path (char *path);
281 extern int tdep_access_reg (struct cursor *c, unw_regnum_t reg,
282 unw_word_t *valp, int write);
283 extern int tdep_access_fpreg (struct cursor *c, unw_regnum_t reg,
284 unw_fpreg_t *valp, int write);
285 #if __linux__
286 extern void tdep_fetch_frame (struct dwarf_cursor *c, unw_word_t ip,
287 int need_unwind_info);
288 extern int tdep_cache_frame (struct dwarf_cursor *c);
289 extern void tdep_reuse_frame (struct dwarf_cursor *c,
290 int frame);
291 extern void tdep_stash_frame (struct dwarf_cursor *c,
292 struct dwarf_reg_state *rs);
293 #endif
294
295 extern int tdep_getcontext_trace (unw_tdep_context_t *);
296 extern int tdep_trace (unw_cursor_t *cursor, void **addresses, int *n);
297
298 #endif /* X86_64_LIBUNWIND_I_H */
299