111
|
1 /****************************************************************************
|
|
2 * *
|
|
3 * GNAT RUN-TIME COMPONENTS *
|
|
4 * *
|
|
5 * T R A C E B A C K *
|
|
6 * *
|
|
7 * C Implementation File *
|
|
8 * *
|
|
9 * Copyright (C) 2000-2016, Free Software Foundation, Inc. *
|
|
10 * *
|
|
11 * GNAT is free software; you can redistribute it and/or modify it under *
|
|
12 * terms of the GNU General Public License as published by the Free Soft- *
|
|
13 * ware Foundation; either version 3, or (at your option) any later ver- *
|
|
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
|
|
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
|
|
16 * or FITNESS FOR A PARTICULAR PURPOSE. *
|
|
17 * *
|
|
18 * As a special exception under Section 7 of GPL version 3, you are granted *
|
|
19 * additional permissions described in the GCC Runtime Library Exception, *
|
|
20 * version 3.1, as published by the Free Software Foundation. *
|
|
21 * *
|
|
22 * You should have received a copy of the GNU General Public License and *
|
|
23 * a copy of the GCC Runtime Library Exception along with this program; *
|
|
24 * see the files COPYING3 and COPYING.RUNTIME respectively. If not, see *
|
|
25 * <http://www.gnu.org/licenses/>. *
|
|
26 * *
|
|
27 * GNAT was originally developed by the GNAT team at New York University. *
|
|
28 * Extensive contributions were provided by Ada Core Technologies Inc. *
|
|
29 * *
|
|
30 ****************************************************************************/
|
|
31
|
|
32 /* This file contains low level support for stack unwinding using GCC intrinsic
|
|
33 functions.
|
|
34 It has been tested on the following configurations:
|
|
35 PowerPC/AiX
|
|
36 PowerPC/Darwin
|
|
37 PowerPC/VxWorks
|
|
38 PowerPC/LynxOS-178
|
|
39 SPARC/Solaris
|
|
40 i386/GNU/Linux
|
|
41 i386/Solaris
|
|
42 i386/NT
|
|
43 i386/OS2
|
|
44 i386/LynxOS
|
|
45 Alpha/VxWorks
|
|
46 Alpha/VMS
|
|
47 */
|
|
48
|
|
49 #ifdef __cplusplus
|
|
50 extern "C" {
|
|
51 #endif
|
|
52
|
|
53 #ifdef __alpha_vxworks
|
|
54 #include "vxWorks.h"
|
|
55 #endif
|
|
56
|
|
57 #ifdef IN_RTS
|
|
58 #define POSIX
|
|
59 #include "tconfig.h"
|
|
60 #include "tsystem.h"
|
|
61 #else
|
|
62 #include "config.h"
|
|
63 #include "system.h"
|
|
64 /* We don't want fancy_abort here. */
|
|
65 #undef abort
|
|
66 #endif
|
|
67
|
|
68 extern int __gnat_backtrace (void **, int, void *, void *, int);
|
|
69
|
|
70 /* The point is to provide an implementation of the __gnat_backtrace function
|
|
71 above, called by the default implementation of the System.Traceback package.
|
|
72
|
|
73 We first have a series of target specific implementations, each included
|
|
74 from a separate C file for readability purposes.
|
|
75
|
|
76 Then come two flavors of a generic implementation: one relying on static
|
|
77 assumptions about the frame layout, and the other one using the GCC EH
|
|
78 infrastructure. The former uses a whole set of macros and structures which
|
|
79 may be tailored on a per target basis, and is activated as soon as
|
|
80 USE_GENERIC_UNWINDER is defined. The latter uses a small subset of the
|
|
81 macro definitions and is activated when USE_GCC_UNWINDER is defined. It is
|
|
82 only available post GCC 3.3.
|
|
83
|
|
84 Finally, there is a default dummy implementation, necessary to make the
|
|
85 linker happy on platforms where the feature is not supported, but where the
|
|
86 function is still referenced by the default System.Traceback. */
|
|
87
|
|
88 #define Lock_Task system__soft_links__lock_task
|
|
89 extern void (*Lock_Task) (void);
|
|
90
|
|
91 #define Unlock_Task system__soft_links__unlock_task
|
|
92 extern void (*Unlock_Task) (void);
|
|
93
|
|
94 /*-------------------------------------*
|
|
95 *-- Target specific implementations --*
|
|
96 *-------------------------------------*/
|
|
97
|
|
98 #if defined (_WIN64) && defined (__SEH__)
|
|
99
|
|
100 #include <windows.h>
|
|
101
|
|
102 #define IS_BAD_PTR(ptr) (IsBadCodePtr((FARPROC)ptr))
|
|
103
|
|
104 int
|
|
105 __gnat_backtrace (void **array,
|
|
106 int size,
|
|
107 void *exclude_min,
|
|
108 void *exclude_max,
|
|
109 int skip_frames)
|
|
110 {
|
|
111 CONTEXT context;
|
|
112 UNWIND_HISTORY_TABLE history;
|
|
113 int i;
|
|
114
|
|
115 /* Get the context. */
|
|
116 RtlCaptureContext (&context);
|
|
117
|
|
118 /* Setup unwind history table (a cached to speed-up unwinding). */
|
|
119 memset (&history, 0, sizeof (history));
|
|
120
|
|
121 i = 0;
|
|
122 while (1)
|
|
123 {
|
|
124 PRUNTIME_FUNCTION RuntimeFunction;
|
|
125 KNONVOLATILE_CONTEXT_POINTERS NvContext;
|
|
126 ULONG64 ImageBase;
|
|
127 VOID *HandlerData;
|
|
128 ULONG64 EstablisherFrame;
|
|
129
|
|
130 /* Get function metadata. */
|
|
131 RuntimeFunction = RtlLookupFunctionEntry
|
|
132 (context.Rip, &ImageBase, &history);
|
|
133
|
|
134 if (!RuntimeFunction)
|
|
135 {
|
|
136 /* In case of failure, assume this is a leaf function. */
|
|
137 context.Rip = *(ULONG64 *) context.Rsp;
|
|
138 context.Rsp += 8;
|
|
139 }
|
|
140 else
|
|
141 {
|
|
142 /* If the last unwinding step failed somehow, stop here. */
|
|
143 if (IS_BAD_PTR(context.Rip))
|
|
144 break;
|
|
145
|
|
146 /* Unwind. */
|
|
147 memset (&NvContext, 0, sizeof (KNONVOLATILE_CONTEXT_POINTERS));
|
|
148 RtlVirtualUnwind (0, ImageBase, context.Rip, RuntimeFunction,
|
|
149 &context, &HandlerData, &EstablisherFrame,
|
|
150 &NvContext);
|
|
151 }
|
|
152
|
|
153 /* 0 means bottom of the stack. */
|
|
154 if (context.Rip == 0)
|
|
155 break;
|
|
156
|
|
157 /* Skip frames. */
|
|
158 if (skip_frames > 1)
|
|
159 {
|
|
160 skip_frames--;
|
|
161 continue;
|
|
162 }
|
|
163 /* Excluded frames. */
|
|
164 if ((void *)context.Rip >= exclude_min
|
|
165 && (void *)context.Rip <= exclude_max)
|
|
166 continue;
|
|
167
|
|
168 array[i++] = (void *)(context.Rip - 2);
|
|
169 if (i >= size)
|
|
170 break;
|
|
171 }
|
|
172 return i;
|
|
173 }
|
|
174 #else
|
|
175
|
|
176 /* No target specific implementation. */
|
|
177
|
|
178 /*----------------------------------------------------------------*
|
|
179 *-- Target specific definitions for the generic implementation --*
|
|
180 *----------------------------------------------------------------*/
|
|
181
|
|
182 /* The stack layout is specified by the target ABI. The "generic" scheme is
|
|
183 based on the following assumption:
|
|
184
|
|
185 The stack layout from some frame pointer is such that the information
|
|
186 required to compute the backtrace is available at static offsets.
|
|
187
|
|
188 For a given frame, the information we are interested in is the saved return
|
|
189 address (somewhere after the call instruction in the caller) and a pointer
|
|
190 to the caller's frame. The former is the base of the call chain information
|
|
191 we store in the tracebacks array. The latter allows us to loop over the
|
|
192 successive frames in the chain.
|
|
193
|
|
194 To initiate the process, we retrieve an initial frame address using the
|
|
195 appropriate GCC builtin (__builtin_frame_address).
|
|
196
|
|
197 This scheme is unfortunately not applicable on every target because the
|
|
198 stack layout is not necessarily regular (static) enough. On targets where
|
|
199 this scheme applies, the implementation relies on the following items:
|
|
200
|
|
201 o struct layout, describing the expected stack data layout relevant to the
|
|
202 information we are interested in,
|
|
203
|
|
204 o FRAME_OFFSET, the offset, from a given frame address or frame pointer
|
|
205 value, at which this layout will be found,
|
|
206
|
|
207 o FRAME_LEVEL, controls how many frames up we get at to start with,
|
|
208 from the initial frame pointer we compute by way of the GCC builtin,
|
|
209
|
|
210 0 is most often the appropriate value. 1 may be necessary on targets
|
|
211 where return addresses are saved by a function in it's caller's frame
|
|
212 (e.g. PPC).
|
|
213
|
|
214 o PC_ADJUST, to account for the difference between a call point (address
|
|
215 of a call instruction), which is what we want in the output array, and
|
|
216 the associated return address, which is what we retrieve from the stack.
|
|
217
|
|
218 o STOP_FRAME, to decide whether we reached the top of the call chain, and
|
|
219 thus if the process shall stop.
|
|
220
|
|
221 :
|
|
222 : stack
|
|
223 | +----------------+
|
|
224 | +-------->| : |
|
|
225 | | | (FRAME_OFFSET) |
|
|
226 | | | : | (PC_ADJUST)
|
|
227 | | layout:| return_address ----------------+
|
|
228 | | | .... | |
|
|
229 +--------------- next_frame | |
|
|
230 | | .... | |
|
|
231 | | | |
|
|
232 | +----------------+ | +-----+
|
|
233 | | : |<- Base fp | | : |
|
|
234 | | (FRAME_OFFSET) | (FRAME_LEVEL) | | : |
|
|
235 | | : | +---> | [1]
|
|
236 | layout:| return_address --------------------> | [0]
|
|
237 | | ... | (PC_ADJUST) +-----+
|
|
238 +---------- next_frame | traceback[]
|
|
239 | ... |
|
|
240 | |
|
|
241 +----------------+
|
|
242
|
|
243 o BASE_SKIP,
|
|
244
|
|
245 Since we inherently deal with return addresses, there is an implicit shift
|
|
246 by at least one for the initial point we are able to observe in the chain.
|
|
247
|
|
248 On some targets (e.g. sparc-solaris), the first return address we can
|
|
249 easily get without special code is even our caller's return address, so
|
|
250 there is a initial shift of two.
|
|
251
|
|
252 BASE_SKIP represents this initial shift, which is the minimal "skip_frames"
|
|
253 value we support. We could add special code for the skip_frames < BASE_SKIP
|
|
254 cases. This is not done currently because there is virtually no situation
|
|
255 in which this would be useful.
|
|
256
|
|
257 Finally, to account for some ABI specificities, a target may (but does
|
|
258 not have to) define:
|
|
259
|
|
260 o FORCE_CALL, to force a call to a dummy function at the very beginning
|
|
261 of the computation. See the PPC AIX target for an example where this
|
|
262 is useful.
|
|
263
|
|
264 o FETCH_UP_FRAME, to force an invocation of __builtin_frame_address with a
|
|
265 positive argument right after a possibly forced call even if FRAME_LEVEL
|
|
266 is 0. See the SPARC Solaris case for an example where this is useful.
|
|
267
|
|
268 */
|
|
269
|
|
270 /*------------------- Darwin 8 (OSX 10.4) or newer ----------------------*/
|
|
271 #if defined (__APPLE__) \
|
|
272 && defined (__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) \
|
|
273 && __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1040
|
|
274
|
|
275 #define USE_GCC_UNWINDER
|
|
276
|
|
277 #if defined (__i386__) || defined (__x86_64__)
|
|
278 #define PC_ADJUST -2
|
|
279 #elif defined (__ppc__) || defined (__ppc64__)
|
|
280 #define PC_ADJUST -4
|
|
281 #elif defined (__arm__)
|
|
282 #define PC_ADJUST -2
|
|
283 #elif defined (__arm64__)
|
|
284 #define PC_ADJUST -4
|
|
285 #else
|
|
286 #error Unhandled darwin architecture.
|
|
287 #endif
|
|
288
|
|
289 /*---------------------------- x86 *BSD --------------------------------*/
|
|
290
|
|
291 #elif defined (__i386__) && \
|
|
292 ( defined (__NetBSD__) || defined (__FreeBSD__) || defined (__OpenBSD__) )
|
|
293
|
|
294 #define USE_GCC_UNWINDER
|
|
295 /* The generic unwinder is not used for this target because the default
|
|
296 implementation doesn't unwind on the BSD platforms. AMD64 targets use the
|
|
297 gcc unwinder for all platforms, so let's keep i386 consistent with that.
|
|
298 */
|
|
299
|
|
300 #define PC_ADJUST -2
|
|
301 /* The minimum size of call instructions on this architecture is 2 bytes */
|
|
302
|
|
303 /*---------------------- ARM VxWorks ------------------------------------*/
|
|
304 #elif (defined (ARMEL) && defined (__vxworks))
|
|
305
|
|
306 #include "vxWorks.h"
|
|
307 #include "version.h"
|
|
308
|
|
309 #define USE_GCC_UNWINDER
|
|
310 #define PC_ADJUST -2
|
|
311
|
|
312 #if (_WRS_VXWORKS_MAJOR >= 7)
|
|
313 #define USING_ARM_UNWINDING 1
|
|
314 #endif
|
|
315
|
|
316 /*---------------------- PPC AIX/PPC Lynx 178/Older Darwin --------------*/
|
|
317 #elif ((defined (_POWER) && defined (_AIX)) || \
|
|
318 (defined (__powerpc__) && defined (__Lynx__) && !defined(__ELF__)) || \
|
|
319 (defined (__ppc__) && defined (__APPLE__)))
|
|
320
|
|
321 #define USE_GENERIC_UNWINDER
|
|
322
|
|
323 struct layout
|
|
324 {
|
|
325 struct layout *next;
|
|
326 void *pad;
|
|
327 void *return_address;
|
|
328 };
|
|
329
|
|
330 #define FRAME_OFFSET(FP) 0
|
|
331 #define PC_ADJUST -4
|
|
332
|
|
333 /* Eventhough the base PPC ABI states that a toplevel frame entry
|
|
334 should to feature a null backchain, AIX might expose a null return
|
|
335 address instead. */
|
|
336
|
|
337 /* Then LynxOS-178 features yet another variation, with return_address
|
|
338 == &<entrypoint>, with two possible entry points (one for the main
|
|
339 process and one for threads). Beware that &bla returns the address
|
|
340 of a descriptor when "bla" is a function. Getting the code address
|
|
341 requires an extra dereference. */
|
|
342
|
|
343 #if defined (__Lynx__)
|
|
344 extern void __start(); /* process entry point. */
|
|
345 extern void __runnit(); /* thread entry point. */
|
|
346 #define EXTRA_STOP_CONDITION(CURRENT) \
|
|
347 ((CURRENT)->return_address == *(void**)&__start \
|
|
348 || (CURRENT)->return_address == *(void**)&__runnit)
|
|
349 #else
|
|
350 #define EXTRA_STOP_CONDITION(CURRENT) (0)
|
|
351 #endif
|
|
352
|
|
353 #define STOP_FRAME(CURRENT, TOP_STACK) \
|
|
354 (((void *) (CURRENT) < (TOP_STACK)) \
|
|
355 || (CURRENT)->return_address == NULL \
|
|
356 || EXTRA_STOP_CONDITION(CURRENT))
|
|
357
|
|
358 /* The PPC ABI has an interesting specificity: the return address saved by a
|
|
359 function is located in it's caller's frame, and the save operation only
|
|
360 takes place if the function performs a call.
|
|
361
|
|
362 To have __gnat_backtrace retrieve its own return address, we then
|
|
363 define ... */
|
|
364
|
|
365 #define FORCE_CALL 1
|
|
366 #define FRAME_LEVEL 1
|
|
367
|
|
368 #define BASE_SKIP 1
|
|
369
|
|
370 /*----------- PPC ELF (GNU/Linux & VxWorks & Lynx178e) -------------------*/
|
|
371
|
|
372 #elif (defined (_ARCH_PPC) && defined (__vxworks)) || \
|
|
373 (defined (__powerpc__) && defined (__Lynx__) && defined(__ELF__)) || \
|
|
374 (defined (__linux__) && defined (__powerpc__))
|
|
375
|
|
376 #define USE_GENERIC_UNWINDER
|
|
377
|
|
378 struct layout
|
|
379 {
|
|
380 struct layout *next;
|
|
381 void *return_address;
|
|
382 };
|
|
383
|
|
384 #define FORCE_CALL 1
|
|
385 #define FRAME_LEVEL 1
|
|
386 /* See the PPC AIX case for an explanation of these values. */
|
|
387
|
|
388 #define FRAME_OFFSET(FP) 0
|
|
389 #define PC_ADJUST -4
|
|
390
|
|
391 /* According to the base PPC ABI, a toplevel frame entry should feature
|
|
392 a null backchain. What happens at signal handler frontiers isn't so
|
|
393 well specified, so we add a safety guard on top. */
|
|
394
|
|
395 #define STOP_FRAME(CURRENT, TOP_STACK) \
|
|
396 ((CURRENT)->next == 0 || ((long)(CURRENT)->next % __alignof__(void*)) != 0)
|
|
397
|
|
398 #define BASE_SKIP 1
|
|
399
|
|
400 /*-------------------------- SPARC Solaris -----------------------------*/
|
|
401
|
|
402 #elif defined (__sun__) && defined (__sparc__)
|
|
403
|
|
404 #define USE_GENERIC_UNWINDER
|
|
405
|
|
406 /* These definitions are inspired from the Appendix D (Software
|
|
407 Considerations) of the SPARC V8 architecture manual. */
|
|
408
|
|
409 struct layout
|
|
410 {
|
|
411 struct layout *next;
|
|
412 void *return_address;
|
|
413 };
|
|
414
|
|
415 #ifdef __arch64__
|
|
416 #define STACK_BIAS 2047 /* V9 ABI */
|
|
417 #else
|
|
418 #define STACK_BIAS 0 /* V8 ABI */
|
|
419 #endif
|
|
420
|
|
421 #define FRAME_LEVEL 0
|
|
422 #define FRAME_OFFSET(FP) (14 * sizeof (void*) + (FP ? STACK_BIAS : 0))
|
|
423 #define PC_ADJUST 0
|
|
424 #define STOP_FRAME(CURRENT, TOP_STACK) \
|
|
425 ((CURRENT)->return_address == 0|| (CURRENT)->next == 0 \
|
|
426 || (void *) (CURRENT) < (TOP_STACK))
|
|
427
|
|
428 /* The SPARC register windows need to be flushed before we may access them
|
|
429 from the stack. This is achieved by way of builtin_frame_address only
|
|
430 when the "count" argument is positive, so force at least one such call. */
|
|
431 #define FETCH_UP_FRAME_ADDRESS
|
|
432
|
|
433 #define BASE_SKIP 2
|
|
434 /* From the frame pointer of frame N, we are accessing the flushed register
|
|
435 window of frame N-1 (positive offset from fp), in which we retrieve the
|
|
436 saved return address. We then end up with our caller's return address. */
|
|
437
|
|
438 /*---------------------------- x86 & x86_64 ---------------------------------*/
|
|
439
|
|
440 #elif defined (__i386__) || defined (__x86_64__)
|
|
441
|
|
442 #if defined (__WIN32)
|
|
443 #include <windows.h>
|
|
444 #define IS_BAD_PTR(ptr) (IsBadCodePtr((FARPROC)ptr))
|
|
445 #elif defined (__sun__)
|
|
446 #define IS_BAD_PTR(ptr) ((unsigned long)ptr == -1UL)
|
|
447 #else
|
|
448 #define IS_BAD_PTR(ptr) 0
|
|
449 #endif
|
|
450
|
|
451 /* Use the dwarf2 unwinder when we expect to have dwarf2 tables at
|
|
452 hand. Backtraces will reliably stop on frames missing such tables,
|
|
453 but our only alternative is the generic unwinder which requires
|
|
454 compilation forcing a frame pointer to be reliable. */
|
|
455
|
|
456 #if (defined (__x86_64__) || defined (__linux__)) && !defined (__USING_SJLJ_EXCEPTIONS__)
|
|
457 #define USE_GCC_UNWINDER
|
|
458 #else
|
|
459 #define USE_GENERIC_UNWINDER
|
|
460 #endif
|
|
461
|
|
462 struct layout
|
|
463 {
|
|
464 struct layout *next;
|
|
465 void *return_address;
|
|
466 };
|
|
467
|
|
468 #define FRAME_LEVEL 1
|
|
469 /* builtin_frame_address (1) is expected to work on this family of targets,
|
|
470 and (0) might return the soft stack pointer, which does not designate a
|
|
471 location where a backchain and a return address might be found. */
|
|
472
|
|
473 #define FRAME_OFFSET(FP) 0
|
|
474 #define PC_ADJUST -2
|
|
475 #define STOP_FRAME(CURRENT, TOP_STACK) \
|
|
476 (IS_BAD_PTR((long)(CURRENT)) \
|
|
477 || IS_BAD_PTR((long)(CURRENT)->return_address) \
|
|
478 || (CURRENT)->return_address == 0 \
|
|
479 || (void *) ((CURRENT)->next) < (TOP_STACK) \
|
|
480 || (void *) (CURRENT) < (TOP_STACK))
|
|
481
|
|
482 #define BASE_SKIP (1+FRAME_LEVEL)
|
|
483
|
|
484 /* On i386 architecture we check that at the call point we really have a call
|
|
485 insn. Possible call instructions are:
|
|
486
|
|
487 call addr16 E8 xx xx xx xx
|
|
488 call reg FF Dx
|
|
489 call off(reg) FF xx xx
|
|
490 lcall addr seg 9A xx xx xx xx xx xx
|
|
491
|
|
492 This check will not catch all cases but it will increase the backtrace
|
|
493 reliability on this architecture.
|
|
494 */
|
|
495
|
|
496 #define VALID_STACK_FRAME(ptr) \
|
|
497 (!IS_BAD_PTR(ptr) \
|
|
498 && (((*((ptr) - 3) & 0xff) == 0xe8) \
|
|
499 || ((*((ptr) - 5) & 0xff) == 0x9a) \
|
|
500 || ((*((ptr) - 1) & 0xff) == 0xff) \
|
|
501 || (((*(ptr) & 0xd0ff) == 0xd0ff))))
|
|
502
|
|
503 /*----------------------------- ia64 ---------------------------------*/
|
|
504
|
|
505 #elif defined (__ia64__) && (defined (__linux__) || defined (__hpux__))
|
|
506
|
|
507 #define USE_GCC_UNWINDER
|
|
508 /* Use _Unwind_Backtrace driven exceptions on ia64 HP-UX and ia64
|
|
509 GNU/Linux, where _Unwind_Backtrace is provided by the system unwind
|
|
510 library. On HP-UX 11.23 this requires patch PHSS_33352, which adds
|
|
511 _Unwind_Backtrace to the system unwind library. */
|
|
512
|
|
513 #define PC_ADJUST -4
|
|
514
|
|
515
|
|
516 #endif
|
|
517
|
|
518 /*---------------------------------------------------------------------*
|
|
519 *-- The post GCC 3.3 infrastructure based implementation --*
|
|
520 *---------------------------------------------------------------------*/
|
|
521
|
|
522 #if defined (USE_GCC_UNWINDER) && (__GNUC__ * 10 + __GNUC_MINOR__ > 33)
|
|
523
|
|
524 /* Conditioning the inclusion on the GCC version is useful to avoid bootstrap
|
|
525 path problems, since the included file refers to post 3.3 functions in
|
|
526 libgcc, and the stage1 compiler is unlikely to be linked against a post 3.3
|
|
527 library. It actually disables the support for backtraces in this compiler
|
|
528 for targets defining USE_GCC_UNWINDER, which is OK since we don't use the
|
|
529 traceback capability in the compiler anyway.
|
|
530
|
|
531 The condition is expressed the way above because we cannot reliably rely on
|
|
532 any other macro from the base compiler when compiling stage1. */
|
|
533
|
|
534 #ifdef USING_ARM_UNWINDING
|
|
535 /* This value is not part of the enumerated reason codes defined in unwind.h
|
|
536 for ARM style unwinding, but is used in the included "C" code, so we
|
|
537 define it to a reasonable value to avoid a compilation error. */
|
|
538 #define _URC_NORMAL_STOP 0
|
|
539 #endif
|
|
540 #include "tb-gcc.c"
|
|
541
|
|
542 /*------------------------------------------------------------------*
|
|
543 *-- The generic implementation based on frame layout assumptions --*
|
|
544 *------------------------------------------------------------------*/
|
|
545
|
|
546 #elif defined (USE_GENERIC_UNWINDER)
|
|
547
|
|
548 #ifndef CURRENT_STACK_FRAME
|
|
549 # define CURRENT_STACK_FRAME ({ char __csf; &__csf; })
|
|
550 #endif
|
|
551
|
|
552 #ifndef VALID_STACK_FRAME
|
|
553 #define VALID_STACK_FRAME(ptr) 1
|
|
554 #endif
|
|
555
|
|
556 #ifndef MAX
|
|
557 #define MAX(x,y) ((x) > (y) ? (x) : (y))
|
|
558 #endif
|
|
559
|
|
560 #ifndef FORCE_CALL
|
|
561 #define FORCE_CALL 0
|
|
562 #endif
|
|
563
|
|
564 /* Make sure the function is not inlined. */
|
|
565 static void forced_callee (void) __attribute__ ((noinline));
|
|
566
|
|
567 static void forced_callee (void)
|
|
568 {
|
|
569 /* Make sure the function is not pure. */
|
|
570 volatile int i __attribute__ ((unused)) = 0;
|
|
571 }
|
|
572
|
|
573 int
|
|
574 __gnat_backtrace (void **array,
|
|
575 int size,
|
|
576 void *exclude_min,
|
|
577 void *exclude_max,
|
|
578 int skip_frames)
|
|
579 {
|
|
580 struct layout *current;
|
|
581 void *top_frame;
|
|
582 void *top_stack ATTRIBUTE_UNUSED;
|
|
583 int cnt = 0;
|
|
584
|
|
585 if (FORCE_CALL)
|
|
586 forced_callee ();
|
|
587
|
|
588 /* Force a call to builtin_frame_address with a positive argument
|
|
589 if required. This is necessary e.g. on SPARC to have the register
|
|
590 windows flushed before we attempt to access them on the stack. */
|
|
591 #if defined (FETCH_UP_FRAME_ADDRESS) && (FRAME_LEVEL == 0)
|
|
592 __builtin_frame_address (1);
|
|
593 #endif
|
|
594
|
|
595 top_frame = __builtin_frame_address (FRAME_LEVEL);
|
|
596 top_stack = CURRENT_STACK_FRAME;
|
|
597 current = (struct layout *) ((size_t) top_frame + FRAME_OFFSET (0));
|
|
598
|
|
599 /* Skip the number of calls we have been requested to skip, accounting for
|
|
600 the BASE_SKIP parameter.
|
|
601
|
|
602 FRAME_LEVEL is meaningless for the count adjustment. It impacts where we
|
|
603 start retrieving data from, but how many frames "up" we start at is in
|
|
604 BASE_SKIP by definition. */
|
|
605
|
|
606 skip_frames = MAX (0, skip_frames - BASE_SKIP);
|
|
607
|
|
608 while (cnt < skip_frames)
|
|
609 {
|
|
610 current = (struct layout *) ((size_t) current->next + FRAME_OFFSET (1));
|
|
611 cnt++;
|
|
612 }
|
|
613
|
|
614 cnt = 0;
|
|
615 while (cnt < size)
|
|
616 {
|
|
617 if (STOP_FRAME (current, top_stack) ||
|
|
618 !VALID_STACK_FRAME(((char *) current->return_address) + PC_ADJUST))
|
|
619 break;
|
|
620
|
|
621 if (current->return_address < exclude_min
|
|
622 || current->return_address > exclude_max)
|
|
623 array[cnt++] = ((char *) current->return_address) + PC_ADJUST;
|
|
624
|
|
625 current = (struct layout *) ((size_t) current->next + FRAME_OFFSET (1));
|
|
626 }
|
|
627
|
|
628 return cnt;
|
|
629 }
|
|
630
|
|
631 #else
|
|
632
|
|
633 /* No target specific implementation and neither USE_GCC_UNWINDER nor
|
|
634 USE_GENERIC_UNWINDER defined. */
|
|
635
|
|
636 /*------------------------------*
|
|
637 *-- The dummy implementation --*
|
|
638 *------------------------------*/
|
|
639
|
|
640 int
|
|
641 __gnat_backtrace (void **array ATTRIBUTE_UNUSED,
|
|
642 int size ATTRIBUTE_UNUSED,
|
|
643 void *exclude_min ATTRIBUTE_UNUSED,
|
|
644 void *exclude_max ATTRIBUTE_UNUSED,
|
|
645 int skip_frames ATTRIBUTE_UNUSED)
|
|
646 {
|
|
647 return 0;
|
|
648 }
|
|
649
|
|
650 #endif
|
|
651
|
|
652 #endif
|
|
653
|
|
654 #ifdef __cplusplus
|
|
655 }
|
|
656 #endif
|