1 /* Target-dependent code for OpenBSD/sparc64.
3 Copyright (C) 2004-2022 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 3 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, see <http://www.gnu.org/licenses/>. */
22 #include "frame-unwind.h"
29 #include "trad-frame.h"
32 #include "obsd-tdep.h"
33 #include "sparc64-tdep.h"
34 #include "solib-svr4.h"
35 #include "bsd-uthread.h"
37 /* Older OpenBSD versions used the traditional NetBSD core file
38 format, even for ports that use ELF. These core files don't use
39 multiple register sets. Instead, the general-purpose and
40 floating-point registers are lumped together in a single section.
41 Unlike on NetBSD, OpenBSD uses a different layout for its
42 general-purpose registers than the layout used for ptrace(2).
44 Newer OpenBSD versions use ELF core files. Here the register sets
45 match the ptrace(2) layout. */
47 /* From <machine/reg.h>. */
48 const struct sparc_gregmap sparc64obsd_gregmap
=
61 const struct sparc_gregmap sparc64obsd_core_gregmap
=
75 sparc64obsd_supply_gregset (const struct regset
*regset
,
76 struct regcache
*regcache
,
77 int regnum
, const void *gregs
, size_t len
)
79 const void *fpregs
= (char *)gregs
+ 288;
83 sparc64_supply_gregset (&sparc64obsd_gregmap
, regcache
, regnum
, gregs
);
87 sparc64_supply_gregset (&sparc64obsd_core_gregmap
, regcache
, regnum
, gregs
);
88 sparc64_supply_fpregset (&sparc64_bsd_fpregmap
, regcache
, regnum
, fpregs
);
92 sparc64obsd_supply_fpregset (const struct regset
*regset
,
93 struct regcache
*regcache
,
94 int regnum
, const void *fpregs
, size_t len
)
96 sparc64_supply_fpregset (&sparc64_bsd_fpregmap
, regcache
, regnum
, fpregs
);
100 /* Signal trampolines. */
102 /* Since OpenBSD 3.2, the sigtramp routine is mapped at a random page
103 in virtual memory. The randomness makes it somewhat tricky to
104 detect it, but fortunately we can rely on the fact that the start
105 of the sigtramp routine is page-aligned. We recognize the
106 trampoline by looking for the code that invokes the sigreturn
107 system call. The offset where we can find that code varies from
110 By the way, the mapping mentioned above is read-only, so you cannot
111 place a breakpoint in the signal trampoline. */
113 /* Default page size. */
114 static const int sparc64obsd_page_size
= 8192;
116 /* Offset for sigreturn(2). */
117 static const int sparc64obsd_sigreturn_offset
[] = {
118 0xf0, /* OpenBSD 3.8 */
119 0xec, /* OpenBSD 3.6 */
120 0xe8, /* OpenBSD 3.2 */
125 sparc64obsd_pc_in_sigtramp (CORE_ADDR pc
, const char *name
)
127 CORE_ADDR start_pc
= (pc
& ~(sparc64obsd_page_size
- 1));
134 for (offset
= sparc64obsd_sigreturn_offset
; *offset
!= -1; offset
++)
136 /* Check for "restore %g0, SYS_sigreturn, %g1". */
137 insn
= sparc_fetch_instruction (start_pc
+ *offset
);
138 if (insn
!= 0x83e82067)
141 /* Check for "t ST_SYSCALL". */
142 insn
= sparc_fetch_instruction (start_pc
+ *offset
+ 8);
143 if (insn
!= 0x91d02000)
152 static struct sparc_frame_cache
*
153 sparc64obsd_frame_cache (frame_info_ptr this_frame
, void **this_cache
)
155 struct sparc_frame_cache
*cache
;
159 return (struct sparc_frame_cache
*) *this_cache
;
161 cache
= sparc_frame_cache (this_frame
, this_cache
);
162 gdb_assert (cache
== *this_cache
);
164 /* If we couldn't find the frame's function, we're probably dealing
165 with an on-stack signal trampoline. */
168 cache
->pc
= get_frame_pc (this_frame
);
169 cache
->pc
&= ~(sparc64obsd_page_size
- 1);
171 /* Since we couldn't find the frame's function, the cache was
172 initialized under the assumption that we're frameless. */
173 sparc_record_save_insn (cache
);
174 addr
= get_frame_register_unsigned (this_frame
, SPARC_FP_REGNUM
);
180 /* We find the appropriate instance of `struct sigcontext' at a
181 fixed offset in the signal frame. */
182 addr
= cache
->base
+ 128 + 16;
183 cache
->saved_regs
= sparc64nbsd_sigcontext_saved_regs (addr
, this_frame
);
189 sparc64obsd_frame_this_id (frame_info_ptr this_frame
, void **this_cache
,
190 struct frame_id
*this_id
)
192 struct sparc_frame_cache
*cache
=
193 sparc64obsd_frame_cache (this_frame
, this_cache
);
195 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
198 static struct value
*
199 sparc64obsd_frame_prev_register (frame_info_ptr this_frame
,
200 void **this_cache
, int regnum
)
202 struct sparc_frame_cache
*cache
=
203 sparc64obsd_frame_cache (this_frame
, this_cache
);
205 return trad_frame_get_prev_register (this_frame
, cache
->saved_regs
, regnum
);
209 sparc64obsd_sigtramp_frame_sniffer (const struct frame_unwind
*self
,
210 frame_info_ptr this_frame
,
213 CORE_ADDR pc
= get_frame_pc (this_frame
);
216 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
217 if (sparc64obsd_pc_in_sigtramp (pc
, name
))
223 static const struct frame_unwind sparc64obsd_frame_unwind
=
225 "sparc64 openbsd sigtramp",
227 default_frame_unwind_stop_reason
,
228 sparc64obsd_frame_this_id
,
229 sparc64obsd_frame_prev_register
,
231 sparc64obsd_sigtramp_frame_sniffer
234 /* Kernel debugging support. */
236 static struct sparc_frame_cache
*
237 sparc64obsd_trapframe_cache (frame_info_ptr this_frame
, void **this_cache
)
239 struct sparc_frame_cache
*cache
;
240 CORE_ADDR sp
, trapframe_addr
;
244 return (struct sparc_frame_cache
*) *this_cache
;
246 cache
= sparc_frame_cache (this_frame
, this_cache
);
247 gdb_assert (cache
== *this_cache
);
249 sp
= get_frame_register_unsigned (this_frame
, SPARC_SP_REGNUM
);
250 trapframe_addr
= sp
+ BIAS
+ 176;
252 cache
->saved_regs
= trad_frame_alloc_saved_regs (this_frame
);
254 cache
->saved_regs
[SPARC64_STATE_REGNUM
].set_addr (trapframe_addr
);
255 cache
->saved_regs
[SPARC64_PC_REGNUM
].set_addr (trapframe_addr
+ 8);
256 cache
->saved_regs
[SPARC64_NPC_REGNUM
].set_addr (trapframe_addr
+ 16);
258 for (regnum
= SPARC_G0_REGNUM
; regnum
<= SPARC_I7_REGNUM
; regnum
++)
259 cache
->saved_regs
[regnum
].set_addr (trapframe_addr
+ 48
260 + (regnum
- SPARC_G0_REGNUM
) * 8);
266 sparc64obsd_trapframe_this_id (frame_info_ptr this_frame
,
267 void **this_cache
, struct frame_id
*this_id
)
269 struct sparc_frame_cache
*cache
=
270 sparc64obsd_trapframe_cache (this_frame
, this_cache
);
272 (*this_id
) = frame_id_build (cache
->base
, cache
->pc
);
275 static struct value
*
276 sparc64obsd_trapframe_prev_register (frame_info_ptr this_frame
,
277 void **this_cache
, int regnum
)
279 struct sparc_frame_cache
*cache
=
280 sparc64obsd_trapframe_cache (this_frame
, this_cache
);
282 return trad_frame_get_prev_register (this_frame
, cache
->saved_regs
, regnum
);
286 sparc64obsd_trapframe_sniffer (const struct frame_unwind
*self
,
287 frame_info_ptr this_frame
,
294 /* Check whether we are in privileged mode, and bail out if we're not. */
295 pstate
= get_frame_register_unsigned (this_frame
, SPARC64_PSTATE_REGNUM
);
296 if ((pstate
& SPARC64_PSTATE_PRIV
) == 0)
299 pc
= get_frame_address_in_block (this_frame
);
300 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
301 if (name
&& strcmp (name
, "Lslowtrap_reenter") == 0)
307 static const struct frame_unwind sparc64obsd_trapframe_unwind
=
309 "sparc64 openbsd trap",
311 default_frame_unwind_stop_reason
,
312 sparc64obsd_trapframe_this_id
,
313 sparc64obsd_trapframe_prev_register
,
315 sparc64obsd_trapframe_sniffer
319 /* Threads support. */
321 /* Offset wthin the thread structure where we can find %fp and %i7. */
322 #define SPARC64OBSD_UTHREAD_FP_OFFSET 232
323 #define SPARC64OBSD_UTHREAD_PC_OFFSET 240
326 sparc64obsd_supply_uthread (struct regcache
*regcache
,
327 int regnum
, CORE_ADDR addr
)
329 struct gdbarch
*gdbarch
= regcache
->arch ();
330 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
331 CORE_ADDR fp
, fp_addr
= addr
+ SPARC64OBSD_UTHREAD_FP_OFFSET
;
334 /* This function calls functions that depend on the global current thread. */
335 gdb_assert (regcache
->ptid () == inferior_ptid
);
337 gdb_assert (regnum
>= -1);
339 fp
= read_memory_unsigned_integer (fp_addr
, 8, byte_order
);
340 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
342 store_unsigned_integer (buf
, 8, byte_order
, fp
);
343 regcache
->raw_supply (SPARC_SP_REGNUM
, buf
);
345 if (regnum
== SPARC_SP_REGNUM
)
349 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== SPARC64_NPC_REGNUM
352 CORE_ADDR i7
, i7_addr
= addr
+ SPARC64OBSD_UTHREAD_PC_OFFSET
;
354 i7
= read_memory_unsigned_integer (i7_addr
, 8, byte_order
);
355 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== -1)
357 store_unsigned_integer (buf
, 8, byte_order
, i7
+ 8);
358 regcache
->raw_supply (SPARC64_PC_REGNUM
, buf
);
360 if (regnum
== SPARC64_NPC_REGNUM
|| regnum
== -1)
362 store_unsigned_integer (buf
, 8, byte_order
, i7
+ 12);
363 regcache
->raw_supply (SPARC64_NPC_REGNUM
, buf
);
366 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== SPARC64_NPC_REGNUM
)
370 sparc_supply_rwindow (regcache
, fp
, regnum
);
374 sparc64obsd_collect_uthread(const struct regcache
*regcache
,
375 int regnum
, CORE_ADDR addr
)
377 struct gdbarch
*gdbarch
= regcache
->arch ();
378 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
382 /* This function calls functions that depend on the global current thread. */
383 gdb_assert (regcache
->ptid () == inferior_ptid
);
385 gdb_assert (regnum
>= -1);
387 if (regnum
== SPARC_SP_REGNUM
|| regnum
== -1)
389 CORE_ADDR fp_addr
= addr
+ SPARC64OBSD_UTHREAD_FP_OFFSET
;
391 regcache
->raw_collect (SPARC_SP_REGNUM
, buf
);
392 write_memory (fp_addr
,buf
, 8);
395 if (regnum
== SPARC64_PC_REGNUM
|| regnum
== -1)
397 CORE_ADDR i7
, i7_addr
= addr
+ SPARC64OBSD_UTHREAD_PC_OFFSET
;
399 regcache
->raw_collect (SPARC64_PC_REGNUM
, buf
);
400 i7
= extract_unsigned_integer (buf
, 8, byte_order
) - 8;
401 write_memory_unsigned_integer (i7_addr
, 8, byte_order
, i7
);
403 if (regnum
== SPARC64_PC_REGNUM
)
407 regcache
->raw_collect (SPARC_SP_REGNUM
, buf
);
408 sp
= extract_unsigned_integer (buf
, 8, byte_order
);
409 sparc_collect_rwindow (regcache
, sp
, regnum
);
413 static const struct regset sparc64obsd_gregset
=
415 NULL
, sparc64obsd_supply_gregset
, NULL
418 static const struct regset sparc64obsd_fpregset
=
420 NULL
, sparc64obsd_supply_fpregset
, NULL
424 sparc64obsd_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
426 sparc_gdbarch_tdep
*tdep
= gdbarch_tdep
<sparc_gdbarch_tdep
> (gdbarch
);
428 tdep
->gregset
= &sparc64obsd_gregset
;
429 tdep
->sizeof_gregset
= 288;
430 tdep
->fpregset
= &sparc64obsd_fpregset
;
431 tdep
->sizeof_fpregset
= 272;
433 /* Make sure we can single-step "new" syscalls. */
434 tdep
->step_trap
= sparcnbsd_step_trap
;
436 frame_unwind_append_unwinder (gdbarch
, &sparc64obsd_frame_unwind
);
437 frame_unwind_append_unwinder (gdbarch
, &sparc64obsd_trapframe_unwind
);
439 sparc64_init_abi (info
, gdbarch
);
440 obsd_init_abi (info
, gdbarch
);
442 /* OpenBSD/sparc64 has SVR4-style shared libraries. */
443 set_solib_svr4_fetch_link_map_offsets
444 (gdbarch
, svr4_lp64_fetch_link_map_offsets
);
445 set_gdbarch_skip_solib_resolver (gdbarch
, obsd_skip_solib_resolver
);
447 /* OpenBSD provides a user-level threads implementation. */
448 bsd_uthread_set_supply_uthread (gdbarch
, sparc64obsd_supply_uthread
);
449 bsd_uthread_set_collect_uthread (gdbarch
, sparc64obsd_collect_uthread
);
452 void _initialize_sparc64obsd_tdep ();
454 _initialize_sparc64obsd_tdep ()
456 gdbarch_register_osabi (bfd_arch_sparc
, bfd_mach_sparc_v9
,
457 GDB_OSABI_OPENBSD
, sparc64obsd_init_abi
);