1 /* Target-dependent code for OpenBSD/sparc64.
3 Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, USA. */
24 #include "frame-unwind.h"
31 #include "trad-frame.h"
33 #include "gdb_assert.h"
35 #include "obsd-tdep.h"
36 #include "sparc64-tdep.h"
37 #include "solib-svr4.h"
38 #include "bsd-uthread.h"
40 /* OpenBSD uses the traditional NetBSD core file format, even for
41 ports that use ELF. The core files don't use multiple register
42 sets. Instead, the general-purpose and floating-point registers
43 are lumped together in a single section. Unlike on NetBSD, OpenBSD
44 uses a different layout for its general-purpose registers than the
45 layout used for ptrace(2). */
47 /* From <machine/reg.h>. */
48 const struct sparc_gregset sparc64obsd_core_gregset
=
62 sparc64obsd_supply_gregset (const struct regset
*regset
,
63 struct regcache
*regcache
,
64 int regnum
, const void *gregs
, size_t len
)
66 const char *regs
= gregs
;
68 sparc64_supply_gregset (&sparc64obsd_core_gregset
, regcache
, regnum
, regs
);
69 sparc64_supply_fpregset (regcache
, regnum
, regs
+ 288);
73 /* Signal trampolines. */
75 /* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page
76 in virtual memory. The randomness makes it somewhat tricky to
77 detect it, but fortunately we can rely on the fact that the start
78 of the sigtramp routine is page-aligned. We recognize the
79 trampoline by looking for the code that invokes the sigreturn
80 system call. The offset where we can find that code varies from
83 By the way, the mapping mentioned above is read-only, so you cannot
84 place a breakpoint in the signal trampoline. */
86 /* Default page size. */
87 static const int sparc64obsd_page_size
= 8192;
89 /* Offset for sigreturn(2). */
90 static const int sparc64obsd_sigreturn_offset
[] = {
91 0xf0, /* OpenBSD 3.8 */
92 0xec, /* OpenBSD 3.6 */
93 0xe8, /* OpenBSD 3.2 */
98 sparc64obsd_pc_in_sigtramp (CORE_ADDR pc
, char *name
)
100 CORE_ADDR start_pc
= (pc
& ~(sparc64obsd_page_size
- 1));
107 for (offset
= sparc64obsd_sigreturn_offset
; *offset
!= -1; offset
++)
109 /* Check for "restore %g0, SYS_sigreturn, %g1". */
110 insn
= sparc_fetch_instruction (start_pc
+ *offset
);
111 if (insn
!= 0x83e82067)
114 /* Check for "t ST_SYSCALL". */
115 insn
= sparc_fetch_instruction (start_pc
+ *offset
+ 8);
116 if (insn
!= 0x91d02000)
125 static struct sparc_frame_cache
*
126 sparc64obsd_frame_cache (struct frame_info
*next_frame
, void **this_cache
)
128 struct sparc_frame_cache
*cache
;
134 cache
= sparc_frame_cache (next_frame
, this_cache
);
135 gdb_assert (cache
== *this_cache
);
137 /* If we couldn't find the frame's function, we're probably dealing
138 with an on-stack signal trampoline. */
141 cache
->pc
= frame_pc_unwind (next_frame
);
142 cache
->pc
&= ~(sparc64obsd_page_size
- 1);
144 /* Since we couldn't find the frame's function, the cache was
145 initialized under the assumption that we're frameless. */
146 cache
->frameless_p
= 0;
147 addr
= frame_unwind_register_unsigned (next_frame
, SPARC_FP_REGNUM
);
153 /* We find the appropriate instance of `struct sigcontext' at a
154 fixed offset in the signal frame. */
155 addr
= cache
->base
+ 128 + 16;
156 cache
->saved_regs
= sparc64nbsd_sigcontext_saved_regs (addr
, next_frame
);
162 sparc64obsd_frame_this_id (struct frame_info
*next_frame
, void **this_cache
,
163 struct frame_id
*this_id
)
165 struct sparc_frame_cache
*cache
=
166 sparc64obsd_frame_cache (next_frame
, this_cache
);
168 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
172 sparc64obsd_frame_prev_register (struct frame_info
*next_frame
,
174 int regnum
, int *optimizedp
,
175 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
176 int *realnump
, gdb_byte
*valuep
)
178 struct sparc_frame_cache
*cache
=
179 sparc64obsd_frame_cache (next_frame
, this_cache
);
181 trad_frame_get_prev_register (next_frame
, cache
->saved_regs
, regnum
,
182 optimizedp
, lvalp
, addrp
, realnump
, valuep
);
185 static const struct frame_unwind sparc64obsd_frame_unwind
=
188 sparc64obsd_frame_this_id
,
189 sparc64obsd_frame_prev_register
192 static const struct frame_unwind
*
193 sparc64obsd_sigtramp_frame_sniffer (struct frame_info
*next_frame
)
195 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
198 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
199 if (sparc64obsd_pc_in_sigtramp (pc
, name
))
200 return &sparc64obsd_frame_unwind
;
205 /* Kernel debugging support. */
207 static struct sparc_frame_cache
*
208 sparc64obsd_trapframe_cache (struct frame_info
*next_frame
, void **this_cache
)
210 struct sparc_frame_cache
*cache
;
211 CORE_ADDR sp
, trapframe_addr
;
217 cache
= sparc_frame_cache (next_frame
, this_cache
);
218 gdb_assert (cache
== *this_cache
);
220 sp
= frame_unwind_register_unsigned (next_frame
, SPARC_SP_REGNUM
);
221 trapframe_addr
= sp
+ BIAS
+ 176;
223 cache
->saved_regs
= trad_frame_alloc_saved_regs (next_frame
);
225 cache
->saved_regs
[SPARC64_STATE_REGNUM
].addr
= trapframe_addr
;
226 cache
->saved_regs
[SPARC64_PC_REGNUM
].addr
= trapframe_addr
+ 8;
227 cache
->saved_regs
[SPARC64_NPC_REGNUM
].addr
= trapframe_addr
+ 16;
229 for (regnum
= SPARC_G0_REGNUM
; regnum
<= SPARC_I7_REGNUM
; regnum
++)
230 cache
->saved_regs
[regnum
].addr
=
231 trapframe_addr
+ 48 + (regnum
- SPARC_G0_REGNUM
) * 8;
237 sparc64obsd_trapframe_this_id (struct frame_info
*next_frame
,
238 void **this_cache
, struct frame_id
*this_id
)
240 struct sparc_frame_cache
*cache
=
241 sparc64obsd_trapframe_cache (next_frame
, this_cache
);
243 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
247 sparc64obsd_trapframe_prev_register (struct frame_info
*next_frame
,
249 int regnum
, int *optimizedp
,
250 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
251 int *realnump
, gdb_byte
*valuep
)
253 struct sparc_frame_cache
*cache
=
254 sparc64obsd_trapframe_cache (next_frame
, this_cache
);
256 trad_frame_get_prev_register (next_frame
, cache
->saved_regs
, regnum
,
257 optimizedp
, lvalp
, addrp
, realnump
, valuep
);
260 static const struct frame_unwind sparc64obsd_trapframe_unwind
=
263 sparc64obsd_trapframe_this_id
,
264 sparc64obsd_trapframe_prev_register
267 static const struct frame_unwind
*
268 sparc64obsd_trapframe_sniffer (struct frame_info
*next_frame
)
274 /* Check whether we are in privileged mode, and bail out if we're not. */
275 pstate
= frame_unwind_register_unsigned (next_frame
, SPARC64_PSTATE_REGNUM
);
276 if ((pstate
& SPARC64_PSTATE_PRIV
) == 0)
279 pc
= frame_unwind_address_in_block (next_frame
, NORMAL_FRAME
);
280 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
281 if (name
&& strcmp (name
, "Lslowtrap_reenter") == 0)
282 return &sparc64obsd_trapframe_unwind
;
288 /* Threads support. */
290 /* Offset wthin the thread structure where we can find %fp and %i7. */
291 #define SPARC64OBSD_UTHREAD_FP_OFFSET 232
292 #define SPARC64OBSD_UTHREAD_PC_OFFSET 240
295 sparc64obsd_supply_uthread (struct regcache
*regcache
,
296 int regnum
, CORE_ADDR addr
)
298 CORE_ADDR fp
, fp_addr
= addr
+ SPARC64OBSD_UTHREAD_FP_OFFSET
;
301 gdb_assert (regnum
>= -1);
303 fp
= read_memory_unsigned_integer (fp_addr
, 8);
304 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
306 store_unsigned_integer (buf
, 8, fp
);
307 regcache_raw_supply (regcache
, SPARC_SP_REGNUM
, buf
);
309 if (regnum
== SPARC_SP_REGNUM
)
313 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== SPARC64_NPC_REGNUM
316 CORE_ADDR i7
, i7_addr
= addr
+ SPARC64OBSD_UTHREAD_PC_OFFSET
;
318 i7
= read_memory_unsigned_integer (i7_addr
, 8);
319 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== -1)
321 store_unsigned_integer (buf
, 8, i7
+ 8);
322 regcache_raw_supply (regcache
, SPARC64_PC_REGNUM
, buf
);
324 if (regnum
== SPARC64_NPC_REGNUM
|| regnum
== -1)
326 store_unsigned_integer (buf
, 8, i7
+ 12);
327 regcache_raw_supply (regcache
, SPARC64_NPC_REGNUM
, buf
);
330 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== SPARC64_NPC_REGNUM
)
334 sparc_supply_rwindow (regcache
, fp
, regnum
);
338 sparc64obsd_collect_uthread(const struct regcache
*regcache
,
339 int regnum
, CORE_ADDR addr
)
344 gdb_assert (regnum
>= -1);
346 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
348 CORE_ADDR fp_addr
= addr
+ SPARC64OBSD_UTHREAD_FP_OFFSET
;
350 regcache_raw_collect (regcache
, SPARC_SP_REGNUM
, buf
);
351 write_memory (fp_addr
,buf
, 8);
354 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== -1)
356 CORE_ADDR i7
, i7_addr
= addr
+ SPARC64OBSD_UTHREAD_PC_OFFSET
;
358 regcache_raw_collect (regcache
, SPARC64_PC_REGNUM
, buf
);
359 i7
= extract_unsigned_integer (buf
, 8) - 8;
360 write_memory_unsigned_integer (i7_addr
, 8, i7
);
362 if (regnum
== SPARC64_PC_REGNUM
)
366 regcache_raw_collect (regcache
, SPARC_SP_REGNUM
, buf
);
367 sp
= extract_unsigned_integer (buf
, 8);
368 sparc_collect_rwindow (regcache
, sp
, regnum
);
373 sparc64obsd_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
375 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
377 tdep
->gregset
= regset_alloc (gdbarch
, sparc64obsd_supply_gregset
, NULL
);
378 tdep
->sizeof_gregset
= 832;
380 /* Make sure we can single-step "new" syscalls. */
381 tdep
->step_trap
= sparcnbsd_step_trap
;
383 frame_unwind_append_sniffer (gdbarch
, sparc64obsd_sigtramp_frame_sniffer
);
384 frame_unwind_append_sniffer (gdbarch
, sparc64obsd_trapframe_sniffer
);
386 sparc64_init_abi (info
, gdbarch
);
388 /* OpenBSD/sparc64 has SVR4-style shared libraries. */
389 set_solib_svr4_fetch_link_map_offsets
390 (gdbarch
, svr4_lp64_fetch_link_map_offsets
);
391 set_gdbarch_skip_solib_resolver (gdbarch
, obsd_skip_solib_resolver
);
393 /* OpenBSD provides a user-level threads implementation. */
394 bsd_uthread_set_supply_uthread (gdbarch
, sparc64obsd_supply_uthread
);
395 bsd_uthread_set_collect_uthread (gdbarch
, sparc64obsd_collect_uthread
);
399 /* Provide a prototype to silence -Wmissing-prototypes. */
400 void _initialize_sparc64obsd_tdep (void);
403 _initialize_sparc64obsd_tdep (void)
405 gdbarch_register_osabi (bfd_arch_sparc
, bfd_mach_sparc_v9
,
406 GDB_OSABI_OPENBSD_ELF
, sparc64obsd_init_abi
);